Jump to content

Land

From Wikipedia, the free encyclopedia

This is an old revision of this page, as edited by Hanif Al Husaini (talk | contribs) at 18:14, 1 December 2022 (Remove year as tere is date). The present address (URL) is a permanent link to this revision, which may differ significantly from the current revision.

Land between bodies of water at Point Reyes National Seashore, California

Land, also called dry land, ground, or earth, is the solid terrestrial surface of planet Earth that is not submerged by the ocean or another body of water. Land makes up 29 percent of Earth's surface and includes the continents and a variety of islands. Earth's land surface is almost entirely covered by regolith, a surface layer of rock, soil and minerals that forms the outer part of Earth's crust. The land is a vital part of Earth's climate system and plays important roles in the carbon cycle, nitrogen cycle, and water cycle. One-third of land is covered in trees, 15 percent in crops, and a tenth in permanent snow and glaciers.

Land terrain varies greatly and consists of mountains, deserts, plains, plateaus, glaciers, and other landforms. In physical geology, the land is divided into two major categories: mountain ranges and relatively flat interiors called cratons. Both are formed over millions of years through plate tectonics. A major part of Earth's water cycle, streams shape the landscape, carved rocks, transport sediments, and replenish groundwater. At high elevations or latitudes, snow is compacted and recrystallized over hundreds or thousands of years to form glaciers, which can be so heavy that they warp the Earth's crust. About 30 percent of land has a dry climate, due to losing more water through evaporation than it gains from precipitation. Since warm air rises, this generates winds, though the Earth's rotation and uneven sun distribution also play a part.

Land is commonly defined as the solid, dry surface of Earth.[1] The word land may also collectively refer to land cover, rivers, shallow lakes, natural resources, non-marine fauna and flora (biosphere), the lower portions of the atmosphere (troposphere), groundwater reserves, and the physical results of human activity on land, such as architecture and agriculture.[2] Even though saturated land, or mud, is common away from the ocean, to anyone in a body of water the shoreline is referred to as where dry land begins.[3]

Though modern terrestrial plants and animals evolved from aquatic creatures, Earth's first cellular life likely originated on land. Survival on land depends on fresh water from rivers, streams, lakes, and glaciers, which constitutes only three percent of the water on Earth. The vast majority of human activity throughout history has occurred in land areas that are habitable and support agriculture and various natural resources. In recent decades, scientists and policymakers have emphasized the need to manage land and its biosphere more sustainably, notably by restoring degraded soil, preserving biodiversity, protecting endangered species, and addressing climate change.

Etymology

The word "land" is derived from the Old English land, meaning 'ground, soil', and 'definite portion of the earth's surface, home region of a person or a people, territory marked by political boundaries'. It evolved from the Proto-Germanic *landą and from the Proto-Indo-European *lendʰ- 'land, open land, heath'. The word has many cognates in other languages, such as Old Norse: land, Template:Lang-ofs, Gothic: land, German: Land, Template:Lang-sga, Middle Welsh: llan 'an open space', Welsh: llan 'enclosure, church', Breton: lann 'heath', Template:Lang-cu 'wasteland, heath', and Czech: lada 'fallow land'. Etymological evidence within Gothic usage suggests that the original meaning of land was 'a definite portion of the earth's surface owned by an individual or home of a nation.' The meaning was extended to 'solid surface of the earth'. The original meaning is now associated with "country".[4][5]

A country or nation may be referred to as the motherland, fatherland, or homeland of its people.[6]: 43  Many countries and other places have names incorporating the suffix -land (e.g. England,[7] Greenland,[8] and New Zealand[9]). The equivalent suffix -stan from Indo-Iranian, ultimately derived from the Proto-Indo-Iranian *sthāna-,[10] is also present in many country and location names, such as Pakistan, Afghanistan and others throughout Central Asia.[11] The suffix is also used more generally, as in Persian rigestân (ریگستان) "place of sand, desert", golestân (گلستان) "place of flowers, garden", gurestân (گورستان) "graveyard, cemetery",[citation needed] and Hindustân (هندوستان) "land of the Indo people".[12]

Physical science

The study of land and its history in general is called geography. Mineralogy is the study of minerals, and petrology is the study of rocks. Soil science is the study of soils, with sub-disciplines in pedology, which focuses on soil formation, and edaphology, which focuses on the relationship between soil and life.

Formation

Artist's conception of Hadean Eon Earth

The earliest material found in the Solar System is dated to 4.5672±0.0006 bya (billion years ago);[13] therefore, the Earth itself must have been formed by accretion around this time. The formation and evolution of the Solar System bodies occurred in tandem with the Sun. In theory, a solar nebula partitions a volume out of a molecular cloud by gravitational collapse, which begins to spin and flatten into a circumstellar disc, out of which the planets then grow (in tandem with the star). A nebula contains gas, ice grains and dust (including primordial nuclides). In nebular theory, planetesimals commence forming as particulate matter accrues by cohesive clumping and then by gravity. The assembly of the primordial Earth proceeded for 10–20 myr.[14] By 4.54±0.04 bya, the primordial Earth had formed.[15][16]

Earth's atmosphere and oceans were formed by volcanic activity and outgassing that included water vapour. The origin of the world's oceans was condensation augmented by water and ice delivered by asteroids, proto-planets, and comets.[17] In this model, atmospheric "greenhouse gases" kept the oceans from freezing while the newly forming Sun was only at 70% luminosity.[18] By 3.5 bya, the Earth's magnetic field was established, which helped prevent the atmosphere from being stripped away by the solar wind.[19] The atmosphere and oceans of the Earth continuously shape the land by eroding and transporting solids on the surface.[20]

Earth's crust formed when molten outer layer of the planet Earth cooled to form a solid mass[21] as the accumulated water vapour began to act in the atmosphere. Once land became capable of supporting life, biodiversity evolved over hundreds of million years, expanding continually except when punctuated by mass extinctions.[22]

The two models[23] that explain land mass propose either a steady growth to the present-day forms[24] or, more likely, a rapid growth[25] early in Earth history[26] followed by a long-term steady continental area.[27][28][29] Continents are formed by plate tectonics, a process ultimately driven by the continuous loss of heat from the Earth's interior. On time scales lasting hundreds of millions of years, the supercontinents have formed and broken apart three times. Roughly 750 mya (million years ago), one of the earliest known supercontinents, Rodinia, began to break apart.[30] The continents later recombined to form Pannotia, 600–540 mya, then finally Pangaea, which also broke apart 180 mya.[31]

Landmasses

Animated map showing the world's continents according to different models.

A continuous area of land surrounded by an ocean is called a landmass. Although it is most often written as one word to distinguish it from the usage "land mass"—the measure of land area—it may also be written as two words.[32] There are four major continuous landmasses on Earth: Afro-Eurasia, the Americas, Antarctica, and Australia, which are then divided into continents.[33] Up to seven geographical regions are commonly regarded as continents. Ordered from largest in area to smallest, these continents are Asia, Africa, North America, South America, Antarctica, Europe, and Australia.[34]

Terrain

Mount Fuji in early summer seen from the International Space Station

Terrain refers to an area of land and its features, or landforms. It affects travel, mapmaking, ecosystems, and surface water flow and distribution. Over a large area, it can influence climate and weather patterns. The terrain of a region largely determines its suitability for human settlement: flatter alluvial plains tend to have better farming soils than steeper, rockier uplands.[35]

Elevation is defined as the vertical distance between an object and sea level, while altitude is defined as the vertical distance from an object to Earth's surface.[36] The elevation of Earth's land surface varies from the low point of −418 m (−1,371 ft) at the Dead Sea, to a maximum altitude of 8,848 m (29,029 ft) at the top of Mount Everest. The mean height of land above sea level is about 797 m (2,615 ft),[37] with 98.9% of dry land situated above sea level.[38]

Relief refers to the difference in elevation within a landscape; for example, flat terrain would have "low relief", while terrain with a large elevation difference between the highest and lowest points would be deemed "high relief". Most land has relatively low relief.[39] The change in elevation between two points of the terrain is called a slope or gradient. A topographic map is a form of terrain cartography which depicts terrain in terms of its elevation, slope, and the orientation of its landforms. It has prominent contour lines, which connect points of similar elevation, while perpendicular slope lines point in the direction of the steepest slope.[40] Hypsometric tints are colors placed between contour lines to indicate elevation relative to sea level.[41]

A difference between uplands, or highlands, and lowlands is drawn in several earth science fields. In river ecology, "upland" rivers are fast-moving and colder than "lowland" rivers, encouraging different species of fish and other aquatic wildlife to live in these habitats. For example, nutrients are more present in slow-moving lowland rivers, encouraging different species of macrophytes to grow there.[42] The term "upland" is also used in wetland ecology, where "upland" plants indicate an area that is not a wetland.[43] In addition, the term moorland refers to upland shrubland biomes with acidic soils, while heathlands are lowland shrublands with acidic soils.[44]

Geomorphology

Geomorphology refers to the study of the natural processes that shape land's surface, creating landforms.[45]: 3  Erosion and tectonics, volcanic eruptions, flooding, weathering, glaciation, the growth of coral reefs, and meteorite impacts are among the processes that constantly reshape Earth's surface over geological time.[46][47]

Erosion transports one part of land to another via natural processes, such as wind, water, ice, and gravity. In contrast, weathering wears away rock and other solid land without transporting the land somewhere else.[48]: 210–211  Natural erosional processes usually take a long time to cause noticeable changes in the landscape—for example, the Grand Canyon was created over the past 70 million years by the Colorado river,[49][50] which scientists estimate continues to erode the canyon at a rate of 0.3 meters (1 foot) every 200 years.[51] However, humans have caused erosion to be 10-40 times faster than normal,[52] causing half the topsoil of the surface of Earth's land to be lost within the past 150 years.[53]

Plate tectonics refers to the theory that Earth's lithosphere is divided into "tectonic plates" that move over the mantle.[48]: 66  This results in continental drift, with continents moving relative to each other.[54] The scientist Alfred Wegener first hypothesized the theory of continental drift in 1912.[55] More researchers gradually developed his idea throughout the 20th century into the widely accepted theory of plate tectonics of today.

Several key characteristics define modern understanding of plate tectonics. The place where two tectonic plates meet is called a plate boundary,[56] with different geological phenomena occurring across different kinds of boundaries. For example, at divergent plate boundaries, seafloor spreading is usually seen,[48]: 74–75  in contrast with the subduction zones of convergent or transform plate boundaries.[48]: 78–80 

Earthquakes and volcanic activity are common in all types of boundaries. Volcanic activity refers to any rupture in Earth's surface where magma escapes, therefore becoming lava.[48]: 170–172  The Ring of Fire, containing two-thirds of the world's volcanos, and over 70% of Earth's seismological activity, comprises plate boundaries surrounding the Pacific Ocean.[57][58]: 68 [59]: 409–452 [a]

Climate

Clouds above Djibouti's, Eritrea's, Somalia's and Yemen's land territories

Earth's land interacts with and influences its climate heavily, since the land's surface heats up and cools down faster than air or water.[60] Latitude, elevation, topography, reflectivity, and land use all have varying effects on climate. The latitude of the land will influence how much solar radiation reaches its surface. High latitudes receive less solar radiation than low latitudes.[60] The land's topography is important in creating and transforming airflow and precipitation. Large landforms, such as mountain ranges, can divert wind energy and make air parcels less dense and therefore able to hold less heat.[60] As air rises, this cooling effect causes condensation and precipitation.

Different types of land cover will influence the land's albedo, a measure of the solar radiation that is reflected, rather than absorbed and transferred to Earth.[61] Vegetation has a relatively low albedo, meaning that vegetated surfaces are good absorbers of the sun's energy. Forests have an albedo of 10–15 percent while grasslands have an albedo of 15–20 percent. In comparison, sandy deserts have an albedo of 25–40 percent.[61]

Land use by humans also plays a role in the regional and global climate. Densely populated cities are warmer and create urban heat islands that have effects on the precipitation, cloud cover, and temperature of the region.[60]

Features

A landform is a natural or manmade[62] land feature. Landforms together make up a given terrain, and their arrangement in the landscape is known as topography. Landforms include hills, mountains, canyons, and valleys, as well as shoreline features such as bays and peninsulas.

Coasts and islands

A simplified diagram of the littoral zone, which includes the coast and nearby waters

The area where land meets the ocean or another large body of water like a lake is called a coast[63] or, alternatively, a "coastline".[64] When land is in contact with bodies of water, the land is likely weathered and eroded. The weathering of a coastline may be impacted by the tides, caused by changes in gravitational forces on larger bodies of water.[45]: 352–353 [65] The precise length of Earth's coastline is indeterminable due to the coastline paradox.[66]

Coasts are important zones in natural ecosystems, often home to a wide range of biodiversity.[67] On land, they harbour important ecosystems such as freshwater or estuarine wetlands, which are important for bird populations and other terrestrial animals. In wave-protected areas they harbor saltmarshes, mangroves or seagrasses, all of which can provide nursery habitat for finfish, shellfish, and other aquatic species. Rocky shores are usually found along exposed coasts and provide habitat for a wide range of sessile animals (e.g. mussels, starfish, barnacles) and various kinds of seaweeds. Along tropical coasts with clear, nutrient-poor water, coral reefs can often be found between depths of 1–50 meters (3.3–164.0 feet).[68]

According to a United Nations atlas, 44% of all people live within 150 km (93 mi) of the sea.[69] Because of their importance in society and high concentration of population, the coast is important for major parts of the global food and economic system, and they provide many ecosystem services to humankind. For example, important human activities happen in port cities. Coastal fisheries (commercial, recreational, and subsistence) and aquaculture are major economic activities and create jobs, livelihoods, and protein for the majority of coastal human populations. Other coastal spaces like beaches and seaside resorts generate large revenues through tourism. Marine coastal ecosystems can also provide protection against sea level rise and tsunamis. In many countries, mangroves are the primary source of wood for fuel (e.g. charcoal) and building material. Coastal ecosystems like mangroves and seagrasses have a much higher capacity for carbon sequestration than many terrestrial ecosystems, and as such can play a critical role in the near future to help mitigate climate change effects by uptake of atmospheric anthropogenic carbon dioxide.[70]

An isolated land habitat surrounded by water is an island,[71]: xxxi  while a chain of islands is an archipelago. The smaller the island, the larger the percentage of its land area will be adjacent to the water, and subsequently will be coast or beach.[72] Islands can be formed by a variety of processes. The Hawaiian islands, for example, even though they are not near a plate boundary, formed from isolated volcanic activity.[71]: 406  Atolls are ring-shaped islands made of coral, created when subsidence causes an island to sink beneath the ocean surface and leaves a ring of reefs around it.[71]: 69 [73]

Mountains and plateaus

Kukenan Tepuy in Gran Sabana National Park, Venezuela
Kukenán-tepui mesa in Gran Sabana National Park, Venezuela

Any highly elevated part of Earth's crust may be called a mountain. Mountains are formed from a number of orogeny events;[45]: 95  for example, where a plate at a convergent plate boundary pushes one plate above the other, mountains could be formed by either collisional events, such that Earth's crust is pushed upwards,[48]: 74  or subductional events, where Earth's crust is pushed into the mantle, causing the crust to melt into diapirs that bubble back to the surface and re-mineralize as dome mountains. The line of mountains in a mountain range are usually formed from the same orogeny events, and their study is important to historical geology.

A plateau, also called a high plain or a tableland, is an area of a highland consisting of flat terrain that is raised sharply above the surrounding area on at least one side, creating steep cliffs or escarpments.[45]: 99  Both volcanic activity such as the upwelling of magma and extrusion of lava, or erosion of mountains caused from water, glaciers, or aeolian processes, can create plateaus. Plateaus are classified according to their surrounding environment as intermontane, piedmont, or continental.[74] A few plateaus may have a small flat top while others have wide ones -- buttes are smaller ones with less extrusive and more intrusive igneous rock, while plateaus or highlands are the widest, and mesas are a general-sized plateau with horizontal bedrock strata.[75][76][77]

Plains and valleys

A small, incised alluvial plain from Red Rock Canyon State Park (California).

Wide, flat areas of land are called plains, which cover more than one-third of Earth's land area.[78] When they occur as lowered areas between mountains, they can create valleys, canyons, gorges, and ravines.[citation needed] A plateau can be thought of as an elevated plain. Plains are known to have fertile soils and be important for agriculture due to their flatness supporting grasses suitable for livestock and facilitating the harvest of crops.[79] Floodplains provided agricultural land for the some of the earliest civilizations. Erosion is often a main driver for the creation of plains and valleys, with rift valleys being a noticeable exception. Fjords are glacial valleys that can be thousands of meters deep, opening out to the sea.[80]

Caves and craters

Any natural void in the ground which can be entered by a human can be considered a cave.[81][82] They have been important to humans as a place of shelter since the dawn of humanity.[83]

Craters are depressions in the ground, but unlike caves, they do not provide shelter or extend underground. They are many kinds of craters, such as impact craters, volcanic calderas, and isostatic depressions, such as the one in Greenland. Karst processes can create both solution caves, the most frequent cave type, and craters, as seen in karst sinkholes.[84]

Layers

The pedosphere is the outermost layer of Earth's continental surface and is composed of soil and subject to soil formation processes. Below it, the lithosphere encompasses both Earth's crust and the uppermost layer of the mantle.[85] The lithosphere rests, or "floats", on top of the mantle below it via isostasy.[48]: 463  Above the solid ground, the troposphere and humans' use of land can be considered layers of the land.[2]

Land cover

Land cover as classified by the International Geosphere-Biosphere Programme (IGBP) into 17 classes

Land cover refers to the material physically present on the land surface, for example, woody crops, herbaceous crops, barren land, and shrub-covered areas. Artificial surfaces (including cities) account for about a third of a percent of all land.[86] Land use refers to human allocation of land for various purposes, including farming, ranching, and recreation (e.g. national parks); worldwide, there are an estimated 16.7 million km2 (6.4 million sq mi) of cropland, and 33.5 million km2 (12.9 million sq mi) of pastureland.[87]

Land cover change detection using remote sensing and geospatial data provides baseline information for assessing the climate change impacts on habitats and biodiversity, as well as natural resources, in the target areas. Land cover change detection and mapping is a key component of interdisciplinary land change science, which uses it to determine the consequences of land change on climate.[88] Land change modeling is used to predict and analyze changes in land cover and use.[89]

Soil

Cross section of rankers soil, with plants and protruding roots near the top

Soil is a mixture of organic matter, minerals, gases, liquids, and organisms that together support life. Soil consists of a solid phase of minerals and organic matter (the soil matrix),[48]: 222  as well as a porous phase that holds gases (the soil atmosphere) and water (the soil solution).[90][91] Accordingly, soil is a three-state system of solids, liquids, and gases.[92] Soil is a product of several factors: the influence of climate, relief (elevation, orientation, and slope of terrain), organisms, and the soil's parent materials (original minerals) interacting over time.[93] It continually undergoes development by way of numerous physical, chemical and biological processes, which include weathering and erosion.[45]: 148–150 

Given its complexity and strong internal connectedness, soil ecologists regard soil as an ecosystem.[94] Soil acts as an engineering medium, a habitat for soil organisms, a recycling system for nutrients and organic wastes, a regulator of water quality, a modifier of atmospheric composition, and a medium for plant growth, making it a critically important provider of ecosystem services.[95] Since soil has a tremendous range of available niches and habitats, it contains a prominent part of the Earth's genetic diversity. A gram of soil can contain billions of organisms, belonging to thousands of species, mostly microbial and largely still unexplored.[96][97]

Soil is a major component of the Earth's ecosystem. The world's ecosystems are impacted in far-reaching ways by the processes carried out in the soil, with effects ranging from ozone depletion and global warming to rainforest destruction and water pollution. With respect to Earth's carbon cycle, soil acts as an important carbon reservoir,[98][99] and it is potentially one of the most reactive to human disturbance[100] and climate change.[101] As the planet warms, it has been predicted that soils will add carbon dioxide to the atmosphere due to increased biological activity at higher temperatures, a positive feedback (amplification).[102] This prediction has, however, been questioned on consideration of more recent knowledge on soil carbon turnover.[103]

Continental crust

Map of the Mohorovičić discontinuity's depth from the surface, otherwise known as the Earth's crust thickness

Continental crust is the layer of igneous, sedimentary, and metamorphic rocks that forms the geological continents and the areas of shallow seabed close to their shores, known as continental shelves. This layer is sometimes called sial because its bulk composition is richer in aluminium silicate and has a lower density compared to the oceanic crust,[104] called sima which is richer in magnesium silicate. Changes in seismic wave velocities have shown that at a certain depth (the Conrad discontinuity), there is a reasonably sharp contrast between the more felsic upper continental crust and the lower continental crust, which is more mafic in character.[105]

The composition of land is not uniform across the Earth, varying between locations and between strata within the same location. The most prominent components of upper continental crust include silicon dioxide, aluminium oxide, and magnesium.[106] The continental crust consists of lower density material such as the igneous rocks granite[107] and andesite. Less common is basalt, a denser volcanic rock that is the primary constituent of the ocean floors.[108] Sedimentary rock is formed from the accumulation of sediment that becomes buried and compacted together. Nearly 75% of the continental surfaces are covered by sedimentary rocks, although they form about 5% of the crust.[109]

The most abundant silicate minerals on Earth's surface include quartz, feldspars, amphibole, mica, pyroxene and olivine.[110] Common carbonate minerals include calcite (found in limestone) and dolomite.[111] The rock that makes up land is thicker than oceanic crust, and it is far more varied in terms of composition. About 31% of this continental crust is submerged in shallow water, forming continental shelves.[106]

Life science

Land provides many ecosystem services, such as mitigating climate change, regulating water supply through drainage basins and river systems, and supporting food production. Land resources are finite, which has led to regulations intended to safeguard these ecosystem services, and a set of practices called sustainable land management.[2]

Land biomes

A biome is an area "characterized by its vegetation, soil, climate, and wildlife."[112][113] There are five major types of biomes on land: grasslands, forests, deserts, tundras, and freshwater.[112] Other biomes include shrublands,[b] wetlands,[c] and polar ice caps.[115] Biomes may contain a variety of ecosystems, which refer to the interaction between organisms within an environment. A habitat is an even narrower term, referring to the environment where a given species lives. Biomes may span more than one continent, and contain a variety of ecosystems and habitats.[116]

A picture of the White Desert in Egypt, with cliffs, dunes, and white chalk rock formations created through erosion by wind and sand
White Desert National Park in Egypt
A forest in Ryssbergen, Sweden
  • A desert is a barren area of landscape where little precipitation occurs and, consequently, living conditions are hostile for plant and animal life. The lack of vegetation exposes the unprotected surface of the ground to denudation. About one-third of Earth's land surface is arid or semi-arid. This includes much of the polar regions, where little precipitation occurs, and which are sometimes called polar deserts or "cold deserts". Deserts can be classified by the amount of precipitation that falls, by their average temperature, by the causes of desertification, or by their geographical location.[117]
  • Tundra is a biome where tree growth is hindered by frigid temperatures and short growing seasons. The term tundra comes through Russian тундра (tundra) from the Kildin Sámi word тӯндар (tūndâr) meaning "uplands", "treeless mountain tract".[118] There are three regions and associated types of tundra: Arctic tundra[119] alpine tundra,[119] and Antarctic tundra.[120]
  • A forest is an area of land dominated by trees. Many definitions of "forest" are used throughout the world, incorporating factors such as tree density, tree height, land use, legal standing, and ecological function. The United Nations' Food and Agriculture Organization (FAO) defines a forest as: "land spanning more than 0.5 hectares with trees higher than 5 meters and a canopy cover of more than 10 per cent, or trees able to reach these thresholds in situ. It does not include land that is predominantly under agricultural or urban use."[121]
  • Grasslands are areas where the vegetation is dominated by grasses (Poaceae). However, sedge (Cyperaceae) and rush (Juncaceae) can also be found, along with variable proportions of legumes like clover and other herbs. Grasslands occur naturally on all continents except Antarctica and are found in most ecoregions of the Earth. Furthermore, grasslands are one of the largest biomes on earth and dominate the landscape worldwide. There are different types of grasslands: natural grasslands, semi-natural grasslands, and agricultural grasslands.[122][page needed]

Fauna and flora

Land plants evolved from green algae, and are called embryophytes. They include trees, shrubs, grass, moss, and flowers. Most plants are vascular plants, meaning that their tissues distribute water and minerals throughout the plant.[123] Through photosynthesis, most plants nourish themselves from sunlight and water, breathing in carbon dioxide and breathing out oxygen. Between 20 and 50% of oxygen is produced by land vegetation.[124]

Unlike plants, terrestrial animals are not a monophyletic group—that is, a group including all terrestrial animals does not encompass all lineages from a common ancestor. This is because there are organisms, such as the whale, that evolved from terrestrial mammals back to an aquatic lifestyle.[125] Many megafauna of the past, such as the dinosaurs, have become extinct due to extinction events, e.g. the Quaternary extinction event.[126]

Humans and land

Land is "deeply intertwined with human development."[2]: 21  Humans depend on land for subsistence, and can develop strong symbolic attachments to it. Access to land can determine "survival and wealth," particularly in developing countries, giving rise to complex power relationships in production and consumption. Most of the world's philosophies and religions recognize a human duty of stewardship towards land and nature.[2]

Culture

A sketch of Safed, one of the four holy cities of Judea in the Holy Land.

Many humans see land as a source of "spirituality, inspiration, and beauty." Many also derive a sense of belonging from land, especially if it also belonged to their ancestors.[2] Various religions teach about a connection between humans and the land (such as veneration of Bhumi, a personification of the Earth in Hinduism,[127] and the obligation to protect land as hima in Islam), and in almost every Indigenous group there are etiological stories about the land they live on.[2] For Indigenous people, connection to the land is an important part of their identity and culture,[128] and some religious groups consider a particular area of land to be sacred, such as the Holy Land in the Abrahamic religions.[129]

Creation myths in many religions involve stories of the creation of the world by a supernatural deity or deities, including accounts wherein the land is separated from the oceans and the air. The Earth itself has often been personified as a deity, in particular a goddess. In many cultures, the mother goddess is also portrayed as a fertility deity. To the Aztecs, Earth was called Tonantzin—"our mother"; to the Incas, Earth was called Pachamama—"mother earth". The Chinese Earth goddess Hou Tu[130] is similar to Gaia, the Greek goddess personifying the Earth. In Norse mythology, the Earth giantess Jörð was the mother of Thor and the daughter of Annar.[131] Ancient Egyptian mythology is different from that of other cultures because Earth (Geb) is male and the sky (Nut) is female.[132]

Ancient Near Eastern cultures conceived of the world as a flat disk of land surrounded by ocean. The Pyramid Texts and Coffin Texts reveal that the ancient Egyptians believed Nun (the ocean) was a circular body surrounding nbwt (a term meaning "dry lands" or "islands").[133] The Hebrew Bible, drawing on other Near Eastern ideas, depicts the Earth as a flat disc floating on water, with another expanse of water above it.[134] A similar model is found in the Homeric account of the 8th century BC in which "Okeanos, the personified body of water surrounding the circular surface of the Earth, is the begetter of all life and possibly of all gods."[135]

The spherical form of the Earth was suggested by early Greek philosophers, a belief espoused by Pythagoras. Contrary to popular belief, most educated people in the Middle Ages did not believe the Earth was flat: this misconception is often called the "Myth of the Flat Earth". As evidenced by thinkers such as Thomas Aquinas, the European belief in a spherical Earth was widespread by this point in time.[136] Prior to circumnavigation of the planet and the introduction of space flight, belief in a spherical Earth was based on observations of the secondary effects of the Earth's shape and parallels drawn with the shape of other planets.[137]

Travel

A train traveling across the Voronezh Oblast, Russia

Humans have commonly traveled for business, pleasure, discovery, and adventure, all made easier in recent human history as a result of technologies like cars, trains, planes, and ships. Land navigation is an aspect of travel and refers to progressing through unfamiliar terrain using navigational tools like maps with references to terrain, a compass, or satellite navigation.[138] Navigation on land is often facilitated by reference to landmarks – enduring and recognizable natural or artificial features that stand out from their nearby environment and are often visible from long distances.[139] Natural landmarks can be characteristic features, such as mountains or plateaus, with examples including Table Mountain in South Africa, Mount Ararat in Turkey, the Grand Canyon in the United States, Uluru in Australia, and Mount Fuji in Japan.[140]

Two major eras of exploration occurred in human history: one of divergence, and one of convergence. The former saw humans moving out of Africa, settling in new lands, and developing distinct cultures in relative isolation.[141] Early explorers settled in Europe and Asia; 14,000 years ago, some crossed the Ice Age land bridge from Siberia to Alaska and moved southbound to settle in the Americas.[142] For the most part, these cultures were ignorant of each other's existence.[141] The second period, occurring over roughly the last 10,000 years, saw increased cross-cultural exchange through trade and exploration, marking a new era of cultural intermingling.[141]

Trade

Human trade has occurred since the prehistoric era. Peter Watson dates the history of long-distance commerce from c. 150,000 years ago.[143] Major trade routes throughout history have existed on land, such as the Silk Road which linked East Asia with Europe[144] and the Amber Road which was used to transfer amber from Northern Europe to the Mediterranean Sea.[145] The Dark Ages led trade to collapse in the West, but it continued to flourish among the kingdoms of Africa, the Middle East, India, China, and Southeast Asia. During the Middle Ages, Central Asia was the economic centre of the world, and luxury goods were commonly traded in Europe. Physical money (either barter or precious metals) was dangerous to carry over a long distance. To address this, a burgeoning banking industry enabled the shift to movable wealth or capital, making it far easier and safer to trade across long distances. After the Age of Sail, international trade mostly occurred along sea routes, notably to prevent intermediary countries from being able to control trade routes and the flow of goods.[citation needed]

In economics, land refers to a factor of production. It can be leased in exchange for rent, and its various resources (trees, oil, metals) can be used as raw material.[146]

Land use

Checkerboarding as a land management strategy: white patches are trees covered with snow, and dark patches are the intact forest.

For more than 10,000 years, humans have engaged in activities on land such as hunting, foraging, controlled burning, land clearing, and agriculture. Beginning with the Neolithic Revolution and the spread of agriculture around the world, human land use has significantly altered terrestrial ecosystems, with an essentially global transformation of Earth's landscape by 3000 years ago.[147]: 30 [148][149] From around 1750, human land use has increased at an accelerating rate due to the Industrial Revolution, which created a greater demand for natural resources and caused rapid population growth.[147]: 34 

Agriculture includes both crop farming and animal husbandry.[150] A third of Earth's land surface is used for agriculture,[151][152]: 126  with estimated 16.7 million km2 (6.4 million sq mi) of cropland and 33.5 million km2 (12.9 million sq mi) of pastureland.[87] This has had significant impacts on Earth's ecosystems. When land is cleared to make way for agriculture, native flora and fauna are replaced with newly introduced crops and livestock.[147]: 31  Excessively high agricultural land use is driven by poor management practices (which lead to lower food yields, necessitating more land use), food demand, food waste, and diets high in meat.[152]: 126 

Urbanization has led to greater population growth in urban areas in the last century. Although urban areas make up less than 3 percent of Earth's land area, the global population shifted from a majority living in rural areas to a majority living in urban areas in 2007.[147]: 35  People living in urban areas depend on food produced in rural areas outside of their cities, which creates greater demand for agriculture and drives land use change well beyond city boundaries.[147]: 35  Urbanization also displaces agricultural land because it mainly takes place on the most fertile land. Urban expansion in peri-urban areas fragments agricultural and natural lands, forcing agriculture to move to less fertile land elsewhere. Because this land is less fertile, more land is needed for the same output, which increases the total agricultural land use.[153]: 119 

Another form of land use is mining, whereby minerals are extracted from the ground using a variety of methods. Evidence of mining activity dates back to around 3000 BCE in Ancient Egypt.[147]: 34  Important minerals include iron ore, mined for use as a raw material, coal, mined for energy production, and gemstones, mined for use in jewellery and currency.[147]: 34 

Law

The phrase "the law of the land" first appeared in 1215 in the Magna Carta, which inspired its usage in the United States Constitution.[154] The idea of common land also originated with medieval English law, and refers collective ownership of land, treating it as a common good.[2] In environmental science, economics, and game theory, the tragedy of the commons refers to individuals' use of common spaces for their own gain, deteriorating the land overall by taking more than their fair share and not cooperating with others.[155] The idea of common land suggests public ownership; but there is still some land that can be privatized as property for an individual, such as a landlord or king. In the developed world, land is expected to be privately owned by an individual with legal title, but in the developing world the right to use land is often divided, with the rights to land resources being given to different people at different times for the same area of land.[2] Beginning in the late 20th century, the international community has begun to recognise Indigenous land rights in law, for example, the Treaty of Waitangi for Māori people, the Act on Greenland Self-Government for Inuit people, and the Indigenous Peoples Rights Act in the Philippines.[128]

Geopolitics

Israel within internationally recognized borders shown in dark green; Israeli-occupied territories shown in light green

Borders are geographical boundaries imposed either by geographic features (oceans, mountain ranges, rivers) or by political entities (governments, states, or subnational entities). Political borders can be established through warfare, colonization, or mutual agreements between the political entities that reside in those areas;[156] the creation of these agreements is called boundary delimitation.[157]

Many wars and other conflicts have occurred in efforts by participants to expand the land under their control, or to assert control of a specific area of considered to hold strategic, historical, or cultural significance. The Mongol Empire of the 13th and 14th centuries became the largest contiguous land empire in history through war and conquest.[158]

In the 19th-century United States, a concept of manifest destiny was developed by various groups, asserting that American settlers were destined to expand across North America. This concept was used to justify military actions against indigenous peoples of North America, and Mexico.[159][160][161][162]

The aggression of Nazi Germany in World War II was motivated in part by the concept of Lebensraum ("living space"), which had first became a geopolitical goal of Imperial Germany in World War I (1914–1918) originally, as the core element of the Septemberprogramm of territorial expansion.[163] The most extreme form of this ideology was supported by the Nazi Party (NSDAP) and Nazi Germany. Lebensraum was one of the leading motivations Nazi Germany had in initiating World War II, and it would continue this policy until the end of World War II.[164]

Environmental issues

Land degradation is "the reduction or loss of the biological or economic productivity and complexity" of land as a result of human activity.[165]: 42  Land degradation is driven by many different activities, including agriculture, urbanization, energy production, and mining.[165]: 43  Humans have altered more than three-quarters of ice-free land through habitation and other use, fundamentally changing ecosystems.[166] Human activity is a major factor in the Holocene extinction,[167] and human-caused climate change is causing rising sea levels and ecosystem loss. Environmental scientists study land's ecosystems, natural resources, biosphere (fauna and flora), troposphere, and the impact of human activity on these.[2] Their recommendations have led to international action to prevent biodiversity loss and desertification, and encourage sustainable forest and waste management.[168] The conservation movement lobbies for the protection of endangered species and the protection of natural areas, such as parks.[169]: 253  International frameworks have focused on analyzing how humans can meet their needs while using land more efficiently and preserving its natural resources, notably under the United Nations' Sustainable Development Goals framework.[168]

Soil degradation

World map of soil degradation

Human land use can cause soil to degrade, both in quality and in quantity.[165]: 44  Soil degradation can be caused by agrochemicals (such as fertilizers, pesticides, and herbicides), infrastructure development, and mining among other activities.[165]: 43–47  There are several different processes that lead to soil degradation. Physical processes, such as erosion, sealing, and crusting, lead to the structural breakdown of the soil. This means water cannot penetrate the soil surface, causing surface runoff.[165]: 44  Chemical processes, such as salinization, acidification, and toxication, lead to chemical imbalances in the soil.[165]: 44  Salinization in particular is detrimental, as it makes land less productive for agriculture and affects at least 20% of all irrigated lands.[152]: 137  Deliberate disruption of soil in the form of tillage can also alter biological processes in the soil, which leads to excessive mineralization and the loss of nutrients.[165]: 44 

Desertification is a type of land degradation in drylands in which fertile areas become increasingly arid as a result of natural processes or human activities, resulting in loss of biological productivity.[170] This spread of arid areas can be influenced by a variety of human factors, such as deforestation, improper land management, overgrazing,[171] anthropogenic climate change,[172] and overexploitation of soil.[173] Throughout geological history, desertification has occurred naturally, though in recent times it is greatly accelerated by human activity.[171][174][175]

Pollution

Ground pollution includes litter. Some landfills, such as the Apex Regional landfill in Las Vegas, can be thousands of acres in size.[176]

Water pollution on land is the contamination of non-oceanic hydrological surface and underground water features such as lakes, ponds, rivers, streams, wetlands, aquifers, reservoirs, and groundwater as a result of human activities.[177]: 6  It may be caused by toxic substances (e.g., oil, metals, plastics, pesticides, persistent organic pollutants, industrial waste products), stressful conditions (e.g., changes of pH, hypoxia or anoxia, increased temperatures, excessive turbidity, unpleasant taste or odor, and changes of salinity), or pathogenic organisms.[citation needed]

Biodiversity loss

Red List Index of biodiversity (2019)

Terrestrial biodiversity loss refers to the worldwide extinction of various land-based species, as well as the local reduction or loss of species in certain habitats. Biodiversity loss is caused by many human activities. Agriculture can cause biodiversity loss as land is converted for agricultural use at a very high rate, particularly in the tropics, which directly causes habitat loss. The use of pesticides and herbicides can also negatively impact the health of local species.[165]: 43  Ecosystems can also be divided and degraded by infrastructure development outside of urban areas.[165]: 46 

Biodiversity loss can sometimes be reversed through ecological restoration or ecological resilience, such as through the restoration of abandoned agricultural areas;[165]: 45  however, it may also be permanent (e.g. through land loss). The planet's ecosystem is quite sensitive: occasionally, minor changes from a healthy equilibrium can have dramatic influence on a food web or food chain, up to and including the coextinction of that entire food chain. Biodiversity loss leads to reduced ecosystem services, and can eventually threaten food security.[178] Earth is currently undergoing its sixth mass extinction (the Holocene extinction) as a result of human activities which push beyond the planetary boundaries. So far, this extinction has proven irreversible.[179][180][181]

Resource depletion

Although humans have used land for its natural resources since ancient times, demand for resources such as timber, minerals, and energy has grown exponentially since the Industrial Revolution due to population growth.[147]: 34  When a natural resource is depleted to the point of diminishing returns, it is considered the overexploitation of that resource.[182] Some natural resources, such as timber, are considered renewable, because with sustainable practices they replenish to their previous levels.[183]: 90  Fossil fuels such as coal are not considered renewable, as they take millions of years to form, with the current supply of coal expected to peak in the middle of the 21st century.[183]: 90  Economic materialism, or consumerism, has influenced destructive patterns of modern resource usage, in contrast with pre-industrial usage.[184]

See also

Notes

  1. ^ The exact number of volcanoes depends on the geographic boundaries used by the source. This number excludes Antarctica and the western islands of Indoesia and includes the Izu, Bonin, and Mariana Islands.
  2. ^ World Wildlife Fund's definition of 14 biomes includes Temperate grasslands, savannas and shrublands, Mediterranean forests, woodlands, and scrub, and Deserts and xeric shrublands.[114]
  3. ^ World Wildlife Fund's definition of 14 biomes includes Flooded grasslands and savannas, and Mangroves, which are both wetlands.[114]

References

  1. ^ Allaby, M.; Park, C. (2013). A Dictionary of Environment and Conservation. Oxford: Oxford University Press. p. 239. ISBN 978-0-19-964166-6.
  2. ^ a b c d e f g h i j "Chapter 1 - Meaning of Land" (PDF). Global Land Outlook (Report). United Nations Convention to Combat Desertification. 2017. p. 21. ISBN 978-92-95110-48-9. Archived (PDF) from the original on September 20, 2022. Retrieved September 18, 2022.
  3. ^ Gniadek, Melissa Myra (August 2011). Unsettled spaces, Unsettled stories; Travel and Historical Narrative in the United States, 1799-1859 (PhD). Cornell University.
  4. ^ Harper, Douglas. "land". Online Etymology Dictionary. Retrieved July 18, 2021.
  5. ^ Hoad, T. F., ed. (2003) [1996]. "land". The Concise Oxford Dictionary of English Etymology. ISBN 978-0-19-283098-2. Retrieved October 19, 2022.
  6. ^ Grosby, Steven (2005). Nationalism: A Very Short Introduction. Oxford: Oxford University Press. ISBN 978-0-19-177628-1.
  7. ^ "England". Online Etymology Dictionary. Retrieved October 20, 2022.
  8. ^ "Greenland". Online Etymology Dictionary. Retrieved October 20, 2022.
  9. ^ "New Zealand". Online Etymology Dictionary. Retrieved October 20, 2022.
  10. ^ Macdonell, A. A. (1929). A practical Sanskrit dictionary with transliteration, accentuation, and etymological analysis throughout. London: Oxford University Press. p. 365. Archived from the original on October 16, 2022. Retrieved September 1, 2022.
  11. ^ Ford, Matt (February 7, 2014). "Kazakhstan's President Is Tired of His Country's Name Ending in 'Stan'". The Atlantic. Retrieved October 28, 2022.
  12. ^ Kapur, Anu (2019). Mapping Place Names of India. Taylor & Francis. ISBN 978-0-429-61421-7.
  13. ^ Bowring, S.; Housh, T. (September 15, 1995). "The Earth's early evolution". Science. 269 (5230): 1535–1540. Bibcode:1995Sci...269.1535B. doi:10.1126/science.7667634. PMID 7667634.
  14. ^ Yin, Q.; Jacobsen, S. B.; Yamashita, K.; Blichert-Toft, J.; Télouk, P.; Albarède, F. (August 29, 2002). "A short timescale for terrestrial planet formation from Hf-W chronometry of meteorites". Nature. 418 (6901): 949–952. Bibcode:2002Natur.418..949Y. doi:10.1038/nature00995. PMID 12198540. S2CID 4391342.
  15. ^ Dalrymple, G. Brent (1991). The age of the earth. Stanford, Calif.: Stanford University Press. ISBN 9780804723312. OCLC 22347190.
  16. ^ Dalrymple, G. Brent (2001). "The age of the Earth in the twentieth century: a problem (mostly) solved". Geological Society of London, Special Publications. 190 (1). Geological Society of London: 205–221. Bibcode:2001GSLSP.190..205D. doi:10.1144/GSL.SP.2001.190.01.14. S2CID 130092094. Archived from the original on November 11, 2007. Retrieved September 20, 2007.
  17. ^ Morbidelli, A.; Chambers, J.; Lunine, J.I.; et al. (2000). "Source regions and time scales for the delivery of water to Earth". Meteoritics & Planetary Science. 35 (6): 1309–1320. Bibcode:2000M&PS...35.1309M. doi:10.1111/j.1945-5100.2000.tb01518.x.
  18. ^ Guinan, E.F.; Ribas, I. (2002). "Our Changing Sun: The Role of Solar Nuclear Evolution and Magnetic Activity on Earth's Atmosphere and Climate". In Montesinos, Benjamin; Gimenez, Alvaro; Guinan, Edward F. (eds.). ASP Conference Proceedings: The Evolving Sun and its Influence on Planetary Environments. San Francisco: Astronomical Society of the Pacific. Bibcode:2002ASPC..269...85G. ISBN 1-58381-109-5.
  19. ^ University of Rochester (March 4, 2010). "Oldest measurement of Earth's magnetic field reveals battle between Sun and Earth for our atmosphere". Physorg.news. Archived from the original on April 27, 2011.
  20. ^ "Ocean Literacy" (PDF). NOAA. Archived from the original (PDF) on November 27, 2014.
  21. ^ Chambers, John E. (2004). "Planetary accretion in the inner Solar System". Earth and Planetary Science Letters. 223 (3–4): 241–252. Bibcode:2004E&PSL.223..241C. doi:10.1016/j.epsl.2004.04.031.
  22. ^ Sahney, S.; Benton, M. J.; Ferry, P. A. (2010). "Links between global taxonomic diversity, ecological diversity and the expansion of vertebrates on land". Biology Letters. 6 (4): 544–547. doi:10.1098/rsbl.2009.1024. PMC 2936204. PMID 20106856.
  23. ^ Rogers, John James William; Santosh, M. (2004). Continents and Supercontinents. Oxford University Press US. p. 48. ISBN 978-0-19-516589-0.
  24. ^ Hurley, P.M.; Rand, J.R. (June 1969). "Pre-drift continental nuclei". Science. 164 (3885): 1229–1242. Bibcode:1969Sci...164.1229H. doi:10.1126/science.164.3885.1229. PMID 17772560.
  25. ^ De Smet, J.; Van Den Berg, A.P.; Vlaar, N.J. (2000). "Early formation and long-term stability of continents resulting from decompression melting in a convecting mantle" (PDF). Tectonophysics. 322 (1–2): 19. Bibcode:2000Tectp.322...19D. doi:10.1016/S0040-1951(00)00055-X. hdl:1874/1653. Archived from the original on March 31, 2021. Retrieved October 2, 2019.
  26. ^ Armstrong, R.L. (1968). "A model for the evolution of strontium and lead isotopes in a dynamic earth". Reviews of Geophysics. 6 (2): 175–199. Bibcode:1968RvGSP...6..175A. doi:10.1029/RG006i002p00175.
  27. ^ Kleine, Thorsten; Palme, Herbert; Mezger, Klaus; Halliday, Alex N. (November 24, 2005). "Hf-W Chronometry of Lunar Metals and the Age and Early Differentiation of the Moon". Science. 310 (5754): 1671–1674. Bibcode:2005Sci...310.1671K. doi:10.1126/science.1118842. PMID 16308422. S2CID 34172110. Archived from the original on July 23, 2021. Retrieved December 1, 2019.
  28. ^ Hong, D.; Zhang, Jisheng; Wang, Tao; Wang, Shiguang; Xie, Xilin (2004). "Continental crustal growth and the supercontinental cycle: evidence from the Central Asian Orogenic Belt". Journal of Asian Earth Sciences. 23 (5): 799. Bibcode:2004JAESc..23..799H. doi:10.1016/S1367-9120(03)00134-2.
  29. ^ Armstrong, R.L. (1991). "The persistent myth of crustal growth". Australian Journal of Earth Sciences. 38 (5): 613–630. Bibcode:1991AuJES..38..613A. CiteSeerX 10.1.1.527.9577. doi:10.1080/08120099108727995.
  30. ^ Li, Z. X.; Bogdanova, S. V.; Collins, A. S.; et al. (2008). "Assembly, configuration, and break-up history of Rodinia: A synthesis" (PDF). Precambrian Research. 160 (1–2): 179–210. Bibcode:2008PreR..160..179L. doi:10.1016/j.precamres.2007.04.021. Archived from the original (PDF) on March 4, 2016. Retrieved February 6, 2016.
  31. ^ Murphy, J.B.; Nance, R.D. (1965). "How do supercontinents assemble?". American Scientist. 92 (4): 324–333. doi:10.1511/2004.4.324. Archived from the original on July 13, 2007. Retrieved March 5, 2007.
  32. ^ Nijman, Jan; Muller, Peter O.; de Blij, H.J. (2017). "Introduction". Regions: Geography: Realms, Regions, and Concepts (17th ed.). Wiley. p. 11. ISBN 978-1-119-30189-9.
  33. ^ McColl, R.W., ed. (2005). "continents". Encyclopedia of World Geography. Vol. 1. p. 215. ISBN 978-0-8160-7229-3. Archived from the original on January 1, 2022. Retrieved August 25, 2022 – via Google Books.
  34. ^ "Continent". National Geographic. Archived from the original on October 1, 2022. Retrieved September 9, 2022.
  35. ^ Dwevedi, A.; Kumar, P.; Kumar, P.; Kumar, Y.; Sharma, Y. K.; Kayastha, A. M. (January 1, 2017). Grumezescu, A. M. (ed.). "15 - Soil sensors: detailed insight into research updates, significance, and future prospects". New Pesticides and Soil Sensors: 561–594. doi:10.1016/B978-0-12-804299-1.00016-3. ISBN 9780128042991. Archived from the original on October 11, 2022. Retrieved October 11, 2022.
  36. ^ "What Is The Difference Between Elevation, Relief And Altitude ? - Mapscaping.com". December 17, 2021. Archived from the original on October 9, 2022. Retrieved October 11, 2022.
  37. ^ National Geophysical Data Center. "Hypsographic Curve of Earth's Surface from ETOPO1". ngdc.noaa.gov. NOAA. Archived from the original on September 15, 2017. Retrieved September 22, 2022.
  38. ^ "Land area where elevation is below 5 meters (% of total land area) | Data". data.worldbank.org. World Bank. Archived from the original on September 20, 2022. Retrieved September 18, 2022.
  39. ^ Summerfield, M.A. (1991). Global Geomorphology. Pearson. p. 537. ISBN 9780582301566.
  40. ^ Mark, David M.; Smith, Barry (2004). "A science of topography: From qualitative ontology to digital representations". In Bishop, Michael P.; Shroder, John F. (eds.). Geographic Information Science and Mountain Geomorphology. Springer-Praxis. pp. 75–100.
  41. ^ Siebert, E. A.; Dornbach, J. E. (1953). "Chart Altitude As A Function Of Hypsometric Layer Tints". Journal of the Institute of Navigation. 3 (8): 270–274. doi:10.1002/j.2161-4296.1953.tb00669.x.
  42. ^ Staniszewski, Ryszard; Jusik, Szymon; Kupiec, Jerzy (January 1, 2012). "Variability of Taxonomic Structure of Macrophytes According to Major Morphological Modifications of Lowland and Upland Rivers With Different Water Trophy". Nauka Przyroda Technologie. 6.
  43. ^ Lichvar, Robert W.; Melvin, Norman C.; Butterwick, Mary L.; Kirchner, William N. (July 2012). National Wetland Plant List Indicator Definitions (PDF). U.S. Army Corps of Engineers. Archived (PDF) from the original on October 12, 2022. Retrieved October 11, 2022.
  44. ^ Polunin, Oleg; Walters, Martin (1985). A Guide to the Vegetation of Britain and Europe. Oxford University Press. p. 220. ISBN 0-19-217713-3.
  45. ^ a b c d e Huggett, Richard John (2011). Fundamentals Of Geomorphology. Routledge Fundamentals of Physical Geography Series (3rd ed.). Routledge. ISBN 978-0-203-86008-3.
  46. ^ Kring, David A. "Terrestrial Impact Cratering and Its Environmental Effects". Lunar and Planetary Laboratory. Archived from the original on May 13, 2011. Retrieved March 22, 2007.
  47. ^ Martin, Ronald (2011). Earth's Evolving Systems: The History of Planet Earth. Jones & Bartlett Learning. ISBN 978-0-7637-8001-2. OCLC 635476788. Archived from the original on October 16, 2022. Retrieved September 22, 2022 – via Google Books.
  48. ^ a b c d e f g h Tarbuck, Edward J.; Lutgens, Frederick K. (2016). Earth: An Introduction to Physical Geology (12th ed.). Pearson. ISBN 978-0-13-407425-2.
  49. ^ Witze, Alexandra (February 26, 2019). "A deeper understanding of the Grand Canyon". Knowable Magazine. doi:10.1146/knowable-022619-1. Archived from the original on June 23, 2022. Retrieved June 23, 2022.
  50. ^ B. Wernicke (January 26, 2011). "The California River and its role in carving Grand Canyon" (PDF). Geological Society of America Bulletin. 123 (7–8): 1288–1316. Bibcode:2011GSAB..123.1288W. doi:10.1130/B30274.1. ISSN 0016-7606. Wikidata Q56082876.
  51. ^ "Canyon". National Geographic. Archived from the original on October 13, 2022. Retrieved October 12, 2022.
  52. ^ Dotterweich, Markus (November 1, 2013). "The history of human-induced soil erosion: Geomorphic legacies, early descriptions and research, and the development of soil conservation – A global synopsis". Geomorphology. 201: 1–34. Bibcode:2013Geomo.201....1D. doi:10.1016/j.geomorph.2013.07.021.
  53. ^ "Soil Erosion and Degradation". World Wildlife Fund. Archived from the original on September 25, 2022. Retrieved October 10, 2022.
  54. ^ University of the Witwatersrand (2019). "Drop of ancient seawater rewrites Earth's history: Research reveals that plate tectonics started on Earth 600 million years before what was believed earlier". ScienceDaily. Archived from the original on August 6, 2019. Retrieved August 11, 2019.
  55. ^ Hughes, Patrick (February 8, 2001). "Alfred Wegener (1880–1930): A Geographic Jigsaw Puzzle". On the Shoulders of Giants. Earth Observatory, NASA. Archived from the original on October 14, 2022. Retrieved December 26, 2007. ... on January 6, 1912, Wegener... proposed instead a grand vision of drifting continents and widening seas to explain the evolution of Earth's geography.
  56. ^ "What are the different types of plate tectonic boundaries?". Ocean Explorer. NOAA. Archived from the original on October 9, 2022. Retrieved October 9, 2022.
  57. ^ Venzke, E., ed. (2013). "Volcanoes of the World, v. 4.3.4". Global Volcanism Program. Smithsonian Institution. doi:10.5479/si.GVP.VOTW4-2013. Archived from the original on August 5, 2022. Retrieved October 14, 2022.
  58. ^ Siebert, L.; Simkin, T.; Kimberly, P. (2010). Volcanoes of the World (3rd ed.). Smithsonian Institution; Berkeley; University of California Press. ISBN 978-0-520-94793-1.
  59. ^ Duda, Seweryn J. (November 1965). "Secular seismic energy release in the circum-Pacific belt". Tectonophysics. 2 (5): 409–452. Bibcode:1965Tectp...2..409D. doi:10.1016/0040-1951(65)90035-1.
  60. ^ a b c d "The Effect of Land Masses on Climate". PBS Learning Media. PBS. Archived from the original on April 2, 2015.
  61. ^ a b Betts, Alan. "The Climate Energy Balance of the Earth". Alan Betts: Atmospheric Research. Archived from the original on March 5, 2015.
  62. ^ Howard, Jeffrey (2017). "Anthropogenic Landforms and Soil Parent Materials". In Howard, Jeffrey (ed.). Anthropogenic Soils. Progress in Soil Science. Cham: Springer International Publishing. pp. 25–51. doi:10.1007/978-3-319-54331-4_3. ISBN 978-3-319-54331-4.
  63. ^ "Coast". The American Heritage Dictionary of the English Language (4th ed.). 2000. Archived from the original on February 1, 2009. Retrieved December 11, 2008.
  64. ^ "Coastline definition". Merriam-Webster. Archived from the original on July 1, 2019. Retrieved June 13, 2015.
  65. ^ Stewart, Robert H. (September 2006). Introduction to Physical Oceanography. Texas A&M University. pp. 301–302.
  66. ^ Mandelbrot, Benoit (May 5, 1967). "How Long Is the Coast of Britain? Statistical Self-Similarity and Fractional Dimension". Science. 156 (3775): 636–638. Bibcode:1967Sci...156..636M. doi:10.1126/science.156.3775.636. PMID 17837158. S2CID 15662830. Retrieved October 26, 2022.
  67. ^ Heckbert, S.; Costanza, R.; Poloczanska, E. S.; Richardson, A. J. (January 1, 2011). "12.10 - Climate Regulation as a Service from Estuarine and Coastal Ecosystems". In Wolanski, Eric; McLusky, Donald (eds.). Treatise on Estuarine and Coastal Science. Vol. 12. Waltham: Academic Press. pp. 199–216. ISBN 978-0-08-087885-0. Archived from the original on October 13, 2022. Retrieved October 11, 2022.
  68. ^ "Coral Reefs". marinebio.org. Retrieved October 28, 2022.
  69. ^ "Human Settlements on the Coast". UN Atlas of the Oceans. July 5, 2018. Archived from the original on July 5, 2018. Retrieved October 11, 2022.
  70. ^ "Coastal functions « World Ocean Review". Archived from the original on October 12, 2022. Retrieved October 11, 2022.
  71. ^ a b c Gillespie, Rosemary G.; Clague, David A., eds. (2009). Encyclopedia of Islands. University of California. ISBN 9780520256491. Archived from the original on December 23, 2021. Retrieved October 22, 2022 – via Google Books.
  72. ^ "Island Biodiversity - Why is it Important?". Convention on Biological Diversity. October 19, 2009. Retrieved October 24, 2022.
  73. ^ Darwin, Charles R. (1842). The structure and distribution of coral reefs. Being the first part of the geology of the voyage of the Beagle, under the command of Capt. Fitzroy, R.N. during the years 1832 to 1836. London: Smith Elder and Co. Archived from the original on September 25, 2006. Retrieved October 14, 2022. {{cite book}}: |website= ignored (help)
  74. ^ Leong, Goh Cheng (October 27, 1995). Certificate Physics And Human Geography (Indian ed.). Oxford University Press. p. 17. ISBN 978-0-19-562816-6. Archived from the original on October 16, 2022. Retrieved October 11, 2022 – via Google Books.
  75. ^ Duszyński, F.; Migoń, P.; Strzelecki, M.C. (2019). "Escarpment retreat in sedimentary tablelands and cuesta landscapes–Landforms, mechanisms and patterns". Earth-Science Reviews. 196 (102890): 102890. Bibcode:2019ESRv..19602890D. doi:10.1016/j.earscirev.2019.102890. S2CID 198410403.
  76. ^ Migoń, P. (2004a). "Mesa". In Goudie, A.S. (ed.). Encyclopedia of Geomorphology. London: Routledge. p. 668. ISBN 9780415272988.
  77. ^ Neuendorf, Klaus K.E.; Mehl Jr., James P.; Jackson, Julia A. (2011). Glossary of Geology (5th ed.). American Geosciences Institute. ISBN 9781680151787.
  78. ^ Brown, Geoff C. [in German]; Hawkesworth, C. J.; Wilson, R. C. L. (1992). Understanding the Earth (2nd ed.). Cambridge University Press. p. 93. ISBN 978-0-521-42740-1. Archived from the original on June 3, 2016 – via Google Books.
  79. ^ Powell, W. Gabe (2009). Identifying Land Use/Land Cover (LULC) Using National Agriculture Imagery Program (NAIP) Data as a Hydrologic Model Input for Local Flood Plain Management (Applied Research Project). Texas State University.
  80. ^ "Fjord". National Geographic. Archived from the original on October 16, 2022. Retrieved October 14, 2022.
  81. ^ Whitney, W. D. (1889). ""Cave, n.1." def. 1.". The Century dictionary: An encyclopedic lexicon of the English language. Vol. 1. New York: The Century Company. p. 871.
  82. ^ "Cave". Oxford English Dictionary (Second Edition on CD-ROM (v. 4.0) ed.). Oxford University Press. 2009.
  83. ^ Marean, Curtis W.; Bar-Matthews, Miryam; Bernatchez, Jocelyn; Fisher, Erich; Goldberg, Paul; Herries, Andy I. R.; Jacobs, Zenobia; Jerardino, Antonieta; Karkanas, Panagiotis; Minichillo, Tom; Nilssen, Peter J.; Thompson, Erin; Watts, Ian; Williams, Hope M. (2007). "Early human use of marine resources and pigment in South Africa during the Middle Pleistocene". Nature. 449 (7164): 905–908. Bibcode:2007Natur.449..905M. doi:10.1038/nature06204. PMID 17943129. S2CID 4387442.
  84. ^ "Solution Caves - Caves and Karst". U.S. National Park Service.
  85. ^ Skinner, B. J.; Porter, S. C. (1987). "The Earth: Inside and Out". Physical Geology. John Wiley & Sons. p. 17. ISBN 0-471-05668-5.
  86. ^ "Land Cover". Food and Agriculture Organization. Food and Agriculture Organization. Archived from the original on January 6, 2022. Retrieved September 18, 2022.
  87. ^ a b Hooke, Roger LeB.; Martín-Duque, José F.; Pedraza, Javier (December 2012). "Land transformation by humans: A review" (PDF). GSA Today. 22 (12): 4–10. doi:10.1130/GSAT151A.1. Archived (PDF) from the original on January 9, 2018. Retrieved September 22, 2022.
  88. ^ Verma, P.; Singh, R.; Singh, P.; Raghubanshi, A.S. (January 1, 2020). "Chapter 1 - Urban ecology – current state of research and concepts". Urban Ecology. Elsevier. pp. 3–16. doi:10.1016/B978-0-12-820730-7.00001-X. ISBN 9780128207307. S2CID 226524905.
  89. ^ Brown, Daniel G.; et al. (2014). Advancing Land Change Modeling: Opportunities and Research Requirements. Washington, DC: The National Academic Press. pp. 11–12. ISBN 978-0-309-28833-0.
  90. ^ Voroney, R. Paul; Heck, Richard J. (2007). "The soil habitat". In Paul, Eldor A. (ed.). Soil microbiology, ecology and biochemistry (3rd ed.). Amsterdam, the Netherlands: Elsevier. pp. 25–49. doi:10.1016/B978-0-08-047514-1.50006-8. ISBN 978-0-12-546807-7.
  91. ^ Taylor, Sterling A.; Ashcroft, Gaylen L. (1972). Physical edaphology: the physics of irrigated and nonirrigated soils. San Francisco, California: W.H. Freeman. ISBN 978-0-7167-0818-6.
  92. ^ McCarthy, David F. (2014). Essentials of soil mechanics and foundations: basic geotechnics (7th ed.). London, United Kingdom: Pearson. ISBN 9781292039398. Archived from the original on October 16, 2022. Retrieved March 27, 2022.
  93. ^ Gilluly, James; Waters, Aaron Clement; Woodford, Alfred Oswald (1975). Principles of geology (4th ed.). San Francisco, California: W.H. Freeman. ISBN 978-0-7167-0269-6.
  94. ^ Ponge, Jean-François (2015). "The soil as an ecosystem". Biology and Fertility of Soils. 51 (6): 645–648. doi:10.1007/s00374-015-1016-1. S2CID 18251180. Archived from the original on December 26, 2021. Retrieved April 3, 2022.
  95. ^ Dominati, Estelle; Patterson, Murray; Mackay, Alec (2010). "A framework for classifying and quantifying the natural capital and ecosystem services of soils". Ecological Economics. 69 (9): 1858‒68. doi:10.1016/j.ecolecon.2010.05.002. Archived (PDF) from the original on August 8, 2017. Retrieved April 10, 2022.
  96. ^ Dykhuizen, Daniel E. (1998). "Santa Rosalia revisited: why are there so many species of bacteria?". Antonie van Leeuwenhoek. 73 (1): 25‒33. doi:10.1023/A:1000665216662. PMID 9602276. S2CID 17779069. Archived from the original on September 26, 2022. Retrieved April 10, 2022.
  97. ^ Torsvik, Vigdis; Øvreås, Lise (2002). "Microbial diversity and function in soil: from genes to ecosystems". Current Opinion in Microbiology. 5 (3): 240‒45. doi:10.1016/S1369-5274(02)00324-7. PMID 12057676. Archived from the original on September 22, 2022. Retrieved April 10, 2022.
  98. ^ Amelung, Wulf; Bossio, Deborah; De Vries, Wim; Kögel-Knabner, Ingrid [in German]; Lehmann, Johannes; Amundson, Ronald; Bol, Roland; Collins, Chris; Lal, Rattan; Leifeld, Jens; Minasny, Buniman; Pan, Gen-Xing; Paustian, Keith; Rumpel, Cornelia; Sanderman, Jonathan; Van Groeningen, Jan Willem; Mooney, Siân; Van Wesemael, Bas; Wander, Michelle; Chabbi, Abad (October 27, 2020). "Towards a global-scale soil climate mitigation strategy" (PDF). Nature Communications. 11 (1): 5427. Bibcode:2020NatCo..11.5427A. doi:10.1038/s41467-020-18887-7. ISSN 2041-1723. PMC 7591914. PMID 33110065. Archived (PDF) from the original on February 26, 2022. Retrieved April 3, 2022.
  99. ^ Pielke, Roger A.; Mahmood, Rezaul; McAlpine, Clive (November 1, 2016). "Land's complex role in climate change". Physics Today. 69 (11): 40–46. Bibcode:2016PhT....69k..40P. doi:10.1063/PT.3.3364. ISSN 0031-9228. Archived from the original on September 25, 2022. Retrieved September 25, 2022.
  100. ^ Pouyat, Richard; Groffman, Peter; Yesilonis, Ian; Hernandez, Luis (2002). "Soil carbon pools and fluxes in urban ecosystems". Environmental Pollution. 116 (Supplement 1): S107–S118. doi:10.1016/S0269-7491(01)00263-9. PMID 11833898. Archived from the original on May 31, 2022. Retrieved April 3, 2022. Our analysis of pedon data from several disturbed soil profiles suggests that physical disturbances and anthropogenic inputs of various materials (direct effects) can greatly alter the amount of C stored in these human "made" soils.
  101. ^ Davidson, Eric A.; Janssens, Ivan A. (2006). "Temperature sensitivity of soil carbon decomposition and feedbacks to climate change" (PDF). Nature. 440 (9 March 2006): 165‒73. Bibcode:2006Natur.440..165D. doi:10.1038/nature04514. PMID 16525463. S2CID 4404915. Archived (PDF) from the original on July 6, 2022. Retrieved April 3, 2022.
  102. ^ Powlson, David (2005). "Will soil amplify climate change?". Nature. 433 (20 January 2005): 204‒05. Bibcode:2005Natur.433..204P. doi:10.1038/433204a. PMID 15662396. S2CID 35007042. Archived from the original on September 22, 2022. Retrieved April 3, 2022.
  103. ^ Bradford, Mark A.; Wieder, William R.; Bonan, Gordon B.; Fierer, Noah; Raymond, Peter A.; Crowther, Thomas W. (2016). "Managing uncertainty in soil carbon feedbacks to climate change" (PDF). Nature Climate Change. 6 (27 July 2016): 751–758. Bibcode:2016NatCC...6..751B. doi:10.1038/nclimate3071. hdl:20.500.11755/c1792dbf-ce96-4dc7-8851-1ca50a35e5e0. S2CID 43955196. Archived (PDF) from the original on April 10, 2017. Retrieved April 3, 2022.
  104. ^ Fairbridge, Rhodes W., ed. (1967). The Encyclopedia of Atmospheric Sciences and Astrogeology. New York: Reinhold Publishing. p. 323. OCLC 430153.
  105. ^ McGuire, Thomas (2005). "Earthquakes and Earth's Interior". Earth Science: The Physical Setting. AMSCO School Publications Inc. pp. 182–184. ISBN 978-0-87720-196-0.
  106. ^ a b Rudnick, Roberta L.; Gao, S. (2014). "Composition of the Continental Crust". In Holland, Heinrich D.; Turekian, Karl K. (eds.). Treatise on Geochemistry. Vol. 4: The Crust (2nd ed.). Elsevier. pp. 1–51. ISBN 978-0-08-098300-4. Archived from the original on September 3, 2022. Retrieved September 3, 2022.
  107. ^ Davis, George H.; Reynolds, Stephen J.; Kluth, Charles F. (2012). "Nature of Structural Geology". Structural Geology of Rocks and Regions (3rd ed.). John Wiley & Sons. p. 18. ISBN 978-0-471-15231-6.
  108. ^ Staff. "Layers of the Earth". Volcano World. Oregon State University. Archived from the original on February 11, 2013. Retrieved March 11, 2007.
  109. ^ Jessey, David. "Weathering and Sedimentary Rocks". California State Polytechnic University, Pomona. Archived from the original on July 3, 2007. Retrieved March 20, 2007.
  110. ^ de Pater, Imke; Lissauer, Jack J. (2010). Planetary Sciences (2nd ed.). Cambridge University Press. p. 154. ISBN 978-0-521-85371-2.
  111. ^ Wenk, Hans-Rudolf; Bulakh, Andreĭ Glebovich [in Russian] (2004). Minerals: their constitution and origin. Cambridge University Press. p. 359. ISBN 978-0-521-52958-7.
  112. ^ a b "The Five Major Types of Biomes | National Geographic Society". National Geographic. May 20, 2022. Archived from the original on October 8, 2022. Retrieved October 4, 2022.
  113. ^ Rull, Valentí (2020). "Organisms: adaption, extinction, and biogeographical reorganizations". Quaternary Ecology, Evolution, and Biogeography. Academic Press. p. 67. ISBN 978-0-12-820473-3.
  114. ^ a b "WWF Terrestrial Ecoregions Of The World (Biomes)". World Wildlife Fund. Archived from the original on July 13, 2022. Retrieved October 11, 2022.
  115. ^ Anesio, Alexandre; Laybourn-Parry, Johanna (October 2011). "Glaciers and ice sheets as a biome". Trends in Ecology and Evolution. 27 (4): 219–225. doi:10.1016/j.tree.2011.09.012. PMID 22000675.
  116. ^ "Biomes, Ecosystems, and Habitats | National Geographic Society". National Geographic. May 20, 2022. Archived from the original on October 7, 2022. Retrieved October 4, 2022.
  117. ^ "desert | National Geographic Society". National Geographic. Archived from the original on August 10, 2022. Retrieved October 11, 2022.
  118. ^ Aapala, Kirsti. "Tunturista jängälle" [From fell to mountain]. Kieli-ikkunat (in Finnish). Archived from the original on October 1, 2006. Retrieved January 19, 2009.
  119. ^ a b "The Tundra Biome". The World's Biomes. University of California, Berkeley. Archived from the original on January 21, 2016. Retrieved March 5, 2006.
  120. ^ "Terrestrial Ecoregions: Antarctica". Wild World. National Geographic Society. Archived from the original on August 5, 2011. Retrieved November 2, 2009.
  121. ^ Global Forest Resources Assessment 2020 – Terms and definitions (PDF). Rome: FAO. 2018. Archived (PDF) from the original on December 8, 2021. Retrieved October 11, 2022.
  122. ^ Gibson, David J. (2009). Grasses and grassland ecology. New York: Oxford University Press. ISBN 978-0-19-154609-9. OCLC 308648056.
  123. ^ Puttick, Mark N.; Morris, Jennifer L.; Williams, Tom A.; Cox, Cymon J.; Edwards, Dianne; Kenrick, Paul; Pressel, Silvia; Wellman, Charles H.; Schneider, Harald (2018). "The Interrelationships of Land Plants and the Nature of the Ancestral Embryophyte". Current Biology. 28 (5): 733–745.e2. doi:10.1016/j.cub.2018.01.063. PMID 29456145.
  124. ^ "How much oxygen comes from the ocean?". National Ocean Service. National Oceanic and Atmospheric Administration. Retrieved August 21, 2022.
  125. ^ Garwood, Russell J.; Edgecombe, Gregory D. (September 2011). "Early Terrestrial Animals, Evolution, and Uncertainty". Evolution: Education and Outreach. 4 (3). New York: Springer Science+Business Media: 489–501. doi:10.1007/s12052-011-0357-y.
  126. ^ Malhi, Yadvinder; Doughty, Christopher E.; Galetti, Mauro; Terborgh, John W. (January 2016). "Megafauna and ecosystem function from the Pleistocene to the Anthropocene". PNAS. 113 (4): 838–846. Bibcode:2016PNAS..113..838M. doi:10.1073/pnas.1502540113. PMC 4743772. PMID 26811442.
  127. ^ "Bhumi, Bhūmi, Bhūmī: 41 definitions". Wisdom Library. April 11, 2009. Archived from the original on October 10, 2022. Retrieved October 10, 2022. Earth (भूमि, bhūmi) is one of the five primary elements (pañcabhūta)
  128. ^ a b United Nations Department of Economic and Social Affairs. "State of the World's Indigenous Peoples, Volume V, Rights to Lands, Territories and Resources" (PDF). Retrieved October 20, 2022.
  129. ^ Bar, Doron (March 9, 2022). "The changing identity of Muslim/Jewish holy places in the State of Israel, 1948–2018". Middle Eastern Studies: 1–12. doi:10.1080/00263206.2022.2047655. S2CID 247371134. Retrieved October 20, 2022.
  130. ^ Werner, E.T.C. (1922). Myths & Legends of China. New York: George G. Harrap and Co. Ltd. Archived from the original on September 7, 2008. Retrieved March 14, 2007.
  131. ^ Lindow, John (2002). Norse Mythology: A Guide to Gods, Heroes, Rituals, and Beliefs. Oxford University Press. p. 205. ISBN 978-0-19-983969-8. Archived from the original on October 14, 2022. Retrieved October 10, 2022 – via Google Books.
  132. ^ Pinch, Geraldine (2002). Handbook of Egyptian Mythology. Handbooks of World Mythology. ABC-CLIO. pp. 135, 173. ISBN 1-57607-763-2.
  133. ^ Pritchard, James B., ed. (March 30, 2016). Ancient Near Eastern Texts Relating to the Old Testament with Supplement. Princeton University Press. p. 374. ISBN 9781400882762. Archived from the original on September 23, 2021. Retrieved November 10, 2020 – via Google Books.
  134. ^ Berlin, Adele (2011). "Cosmology and creation". In Berlin, Adele; Grossman, Maxine (eds.). The Oxford Dictionary of the Jewish Religion. Oxford University Press. pp. 188–189. ISBN 978-0-19-973004-9. Archived from the original on June 11, 2016 – via Google Books.
  135. ^ Gottlieb, Anthony (2000). The Dream of Reason. Penguin. p. 6. ISBN 978-0-393-04951-0.
  136. ^ Russell, Jeffrey B. "The Myth of the Flat Earth". American Scientific Affiliation. Archived from the original on September 3, 2011. Retrieved March 14, 2007; but see also Cosmas Indicopleustes.
  137. ^ Jacobs, James Q. (February 1, 1998). "Archaeogeodesy, a Key to Prehistory". Archived from the original on April 23, 2007. Retrieved April 21, 2007.
  138. ^ Hofmann-Wellenhof, Bernhard; Legat, K.; Wieser, M.; Lichtenegger, H. (2007). Navigation: Principles of Positioning and Guidances. Springer. pp. 5–6. ISBN 978-3-211-00828-7.
  139. ^ "LANDMARK | meaning in the Cambridge English Dictionary". dictionary.cambridge.org. Archived from the original on August 13, 2021. Retrieved August 2, 2020.
  140. ^ "2012 Tourism Highlights" (PDF). World Tourism Organization. June 2012. Archived from the original (PDF) on July 9, 2012. Retrieved June 17, 2012.
  141. ^ a b c Fernández-Armesto, Felipe (October 17, 2007). Pathfinders: A Global History of Exploration. W. W. Norton & Company. ISBN 978-0-393-24247-8. Archived from the original on October 16, 2022. Retrieved October 6, 2022 – via Google Books.
  142. ^ Royal Geographical Society (2008). Atlas of Exploration. Oxford University Press. ISBN 978-0-19-534318-2. Archived from the original on October 16, 2022. Retrieved October 6, 2022 – via Google Books.
  143. ^ Watson (2005), Introduction.
  144. ^ National Geographic Society (July 26, 2019). "The Silk Road". National Geographic Society. Archived from the original on March 23, 2022. Retrieved September 25, 2022.
  145. ^ Singer, Graciela Gestoso. "Graciela Gestoso Singer, "Amber in the Ancient Near East", i-Medjat No. 2 (December 2008). Papyrus Electronique des Ankou". Archived from the original on September 25, 2022. Retrieved September 25, 2022.
  146. ^ "Undrestanding Land in Business and Economics". Investopedia. Archived from the original on September 26, 2022. Retrieved September 18, 2022.
  147. ^ a b c d e f g h "Chapter 2 - Brief History of Land Use—" (PDF). Global Land Outlook (Report). United Nations Convention to Combat Desertification. 2017. ISBN 978-92-95110-48-9. Retrieved November 3, 2022.
  148. ^ Ellis, Erle; Goldewijk, Kees Klein; Gaillard, Marie-José; Kaplan, Jed O.; Thornton, Alexa; Powell, Jeremy; Garcia, Santiago Munevar; Beaudoin, Ella; Zerboni, Andrea (August 30, 2019). "Archaeological assessment reveals Earth's early transformation through land use". Science. 365 (6456): 897–902. Bibcode:2019Sci...365..897S. doi:10.1126/science.aax1192. hdl:10150/634688. ISSN 0036-8075. PMID 31467217. S2CID 201674203.
  149. ^ Ellis, Erle C.; Gauthier, Nicolas; Goldewijk, Kees Klein; Bird, Rebecca Bliege; Boivin, Nicole; Díaz, Sandra; Fuller, Dorian Q.; Gill, Jacquelyn L.; Kaplan, Jed O.; Kingston, Naomi; Locke, Harvey (April 27, 2021). "People have shaped most of terrestrial nature for at least 12,000 years". Proceedings of the National Academy of Sciences. 118 (17): e2023483118. Bibcode:2021PNAS..11823483E. doi:10.1073/pnas.2023483118. ISSN 0027-8424. PMC 8092386. PMID 33875599.
  150. ^ Safety and health in agriculture. International Labour Organization. 1999. p. 77. ISBN 978-92-2-111517-5. Archived from the original on July 22, 2011. Retrieved September 13, 2010 – via Google Books. defined agriculture as 'all forms of activities connected with growing, harvesting and primary processing of all types of crops, with the breeding, raising and caring for animals, and with tending gardens and nurseries'.
  151. ^ "Agricultural land (% of land area) | Data". data.worldbank.org. Archived from the original on May 30, 2019. Retrieved September 25, 2022.
  152. ^ a b c "Chapter 7 - Food Security and Agriculture" (PDF). Global Land Outlook (Report). United Nations Convention to Combat Desertification. 2017. ISBN 978-92-95110-48-9. Retrieved November 14, 2022.
  153. ^ "Chapter 6 - Scenarios of Change—" (PDF). Global Land Outlook (Report). United Nations Convention to Combat Desertification. 2017. ISBN 978-92-95110-48-9. Retrieved November 14, 2022.
  154. ^ "Law of the land". Cornell Law School. Cornell University. Archived from the original on February 15, 2022. Retrieved October 15, 2022.
  155. ^ Purvis, V. (March 14, 1970). "Self-interest and the Common Good". BMJ. 1 (5697): 692. doi:10.1136/bmj.1.5697.692-c. ISSN 0959-8138. S2CID 71492205. Archived from the original on October 16, 2022. Retrieved October 15, 2022.
  156. ^ Slater, Terry (2016). "The Rise and Spread of Capitalism". In Daniels, Peter; Bradshaw, Michael; Shaw, Denis; Sidaway, James; Hall, Tim (eds.). An Introduction To Human Geography (5th ed.). Pearson. p. 47. ISBN 978-1-292-12939-6.
  157. ^ Sidaway, James; Grundy-Warr, Carl (2016). "The Place of the Nation-State". In Daniels, Peter; Bradshaw, Michael; Shaw, Denis; Sidaway, James; Hall, Tim (eds.). An Introduction To Human Geography (5th ed.). Pearson. p. 449. ISBN 978-1-292-12939-6.
  158. ^ Morgan, David (1986). The Mongols. Oxford, U.K.: Blackwell. p. 5. ISBN 0-631-13556-1. OCLC 12806959.
  159. ^ Merk, Frederick; Merck, Lois Bannister (1963). Manifest Destiny and Mission in American History. pp. 215–216. ISBN 9780674548053 – via Google Books.
  160. ^ Howe, D.W. (2007). What Hath God Wrought: The Transformation of America, 1815-1848. Oxford History of the United States. Oxford University Press. p. 706. ISBN 978-0-19-972657-8 – via Google Books.
  161. ^ Randazzo, Michele E.; Hitt, John R. (2019). LexisNexis Practice Guide: Massachusetts Administrative Law and Practice (6 ed.). LexisNexis. p. 29. ISBN 9781522182887 – via Google Books.
  162. ^ Byrnes, Mark Eaton (2001). James K. Polk: A Biographical Companion (illustrated ed.). ABC-CLIO. p. 128. ISBN 9781576070567 – via Google Books.
  163. ^ Evans, Graham; Newnham, Jeffrey, eds. (1998). Penguin Dictionary of International relations. Penguin Books. p. 301. ISBN 978-0140513974. Geopolitics (excerpt).
  164. ^ Smith, Woodruff D. The Ideological Origins of Nazi Imperialism. Oxford University Press. p. 84.
  165. ^ a b c d e f g h i j "Chapter 3 - Drivers of Change" (PDF). Global Land Outlook (Report). United Nations Convention to Combat Desertification. 2017. ISBN 978-92-95110-48-9. Retrieved November 4, 2022.
  166. ^ Ellis, Erle C.; Ramankutty, Navin (October 1, 2008). "Putting people in the map: anthropogenic biomes of the world". Frontiers in Ecology and the Environment. 6 (8): 439–447. doi:10.1890/070062. ISSN 1540-9295. S2CID 3598526.
  167. ^ Turvey, Samuel T. (May 28, 2009). Holocene Extinctions. Oxford University Press. ISBN 978-0-19-157998-1 – via Google Books.
  168. ^ a b "Goal 15 | Department of Economic and Social Affairs". United Nations. Archived from the original on September 26, 2022. Retrieved September 26, 2022.
  169. ^ Evans, James (2016). "Social Constructions of Nature". In Daniels, Peter; Bradshaw, Michael; Shaw, Denis; Sidaway, James; Hall, Tim (eds.). An Introduction To Human Geography (5th ed.). Pearson. ISBN 978-1-292-12939-6.
  170. ^ Geist, Helmut [in German] (2005). The causes and progression of desertification. Ashgate Publishing. ISBN 978-0-7546-4323-4. Archived from the original on October 16, 2022. Retrieved September 26, 2022 – via Google Books.
  171. ^ a b Liu, Ye; Xue, Yongkang (March 5, 2020). "Expansion of the Sahara Desert and shrinking of frozen land of the Arctic". Scientific Reports. 10 (1): 4109. Bibcode:2020NatSR..10.4109L. doi:10.1038/s41598-020-61085-0. PMC 7057959. PMID 32139761.
  172. ^ Zeng, Ning; Yoon, Jinho (September 1, 2009). "Expansion of the world's deserts due to vegetation-albedo feedback under global warming". Geophysical Research Letters. 36 (17): L17401. Bibcode:2009GeoRL..3617401Z. doi:10.1029/2009GL039699. ISSN 1944-8007. S2CID 1708267.
  173. ^ "Sustainable development of drylands and combating desertification". Food and Agriculture Organization. Archived from the original on August 4, 2017. Retrieved June 21, 2016.
  174. ^ An, Hui; Tang, Zhuangsheng; Keesstra, Saskia; Shangguan, Zhouping (July 1, 2019). "Impact of desertification on soil and plant nutrient stoichiometry in a desert grassland". Scientific Reports. 9 (1): 9422. Bibcode:2019NatSR...9.9422A. doi:10.1038/s41598-019-45927-0. PMC 6603008. PMID 31263198.
  175. ^ Han, Xueying; Jia, Guangpu; Yang, Guang; Wang, Ning; Liu, Feng; Chen, Haoyu; Guo, Xinyu; Yang, Wenbin; Liu, Jing (December 10, 2020). "Spatiotemporal dynamic evolution and driving factors of desertification in the Mu Us Sandy Land in 30 years". Scientific Reports. 10 (1): 21734. Bibcode:2020NatSR..1021734H. doi:10.1038/s41598-020-78665-9. PMC 7729393. PMID 33303886.
  176. ^ Schoenmann, Joe (December 17, 2008). "Official calls for sort reform". Las Vegas Sun. Archived from the original on January 8, 2009. Retrieved December 20, 2008.
  177. ^ Von Sperling, Marcos (2015). "Wastewater Characteristics, Treatment and Disposal". IWA Publishing. 6. doi:10.2166/9781780402086. ISBN 9781780402086. Archived from the original on June 21, 2022. Retrieved September 26, 2022.
  178. ^ Cardinale BJ, Duffy JE, Gonzalez A, et al. (June 2012). "Biodiversity loss and its impact on humanity" (PDF). Nature. 486 (7401): 59–67. Bibcode:2012Natur.486...59C. doi:10.1038/nature11148. PMID 22678280. S2CID 4333166. Archived (PDF) from the original on September 21, 2017. Retrieved September 26, 2022. ...at the first Earth Summit, the vast majority of the world's nations declared that human actions were dismantling the Earth's ecosystems, eliminating genes, species and biological traits at an alarming rate. This observation led to the question of how such loss of biological diversity will alter the functioning of ecosystems and their ability to provide society with the goods and services needed to prosper.
  179. ^ Bradshaw CJ, Ehrlich PR, Beattie A, et al. (2021). "Underestimating the Challenges of Avoiding a Ghastly Future". Frontiers in Conservation Science. 1. doi:10.3389/fcosc.2020.615419.
  180. ^ Ripple WJ, Wolf C, Newsome TM, Galetti M, Alamgir M, Crist E, Mahmoud MI, Laurance WF (November 13, 2017). "World Scientists' Warning to Humanity: A Second Notice". BioScience. 67 (12): 1026–1028. doi:10.1093/biosci/bix125. Moreover, we have unleashed a mass extinction event, the sixth in roughly 540 million years, wherein many current life forms could be annihilated or at least committed to extinction by the end of this century.
  181. ^ Cowie RH, Bouchet P, Fontaine B (April 2022). "The Sixth Mass Extinction: fact, fiction or speculation?". Biological Reviews of the Cambridge Philosophical Society. 97 (2): 640–663. doi:10.1111/brv.12816. PMID 35014169. S2CID 245889833.
  182. ^ Ehrlich, Paul R.; Ehrlich, Anne H. (1972). Population, Resources, Environment: Issues in Human Ecology (2nd ed.). W. H. Freeman and Company. p. 127. ISBN 0-7167-0695-4.
  183. ^ a b "Chapter 5 - Land Resources and Human Security" (PDF). Global Land Outlook (Report). United Nations Convention to Combat Desertification. 2017. ISBN 978-92-95110-48-9. Retrieved November 3, 2022.
  184. ^ Wang, Luxiao; Gu, Dian; Jiang, Jiang; Sun, Ying (April 5, 2019). "The Not-So-Dark Side of Materialism: Can Public Versus Private Contexts Make Materialists Less Eco-Unfriendly?". Frontiers in Psychology. 10: 790. doi:10.3389/fpsyg.2019.00790. ISSN 1664-1078. PMC 6460118. PMID 31024411.

Sources