Everything about Arable Land totally explained
In
geography,
arable land (from
Latin arare, to
plough) is an
agricultural term, meaning
land that can be used for growing
crops.
Of the earth's 148,000,000 km² (57 million square miles) of land, approximately 31,000,000 km² (12 million square miles) are arable; however, arable land is currently being lost at the rate of over 100,000 km² (38,610 square miles) per year. A major element of arable land loss comes from
deforestation (starting in the
Middle Ages in
Europe as well as
Asia). Such deforestation continues to the present day primarily in tropical countries by commercial over-exploitation of tropical forest. At times, deforestation can be so extreme that it leads to
desertification, or the total loss of arable land, as has occurred in portions of the central highland plateau of
Madagascar following extensive
slash-and-burn activity.
A smaller, but important loss of arable land arises from the lack of renewal of rich flooding sediment due to flood control works. A large part of the arable land on earth is around the largest rivers on earth; for example, the
Nile River, the
Mississippi River, the
Tigris and
Euphrates Rivers, the
Yellow River, the
Amazon River, the
Ganges and the
Rhine River.
The most productive portion of arable land is that from sediments left by those rivers and the sea in geological times. In modern times, the rivers don't generally flood as much agricultural land, due to the demands of
flood control to support intensive agriculture required of a heavily-populated Earth.
The Nile continues to flood regularly, overspilling its banks. When the flood is over, the waters recede, leaving behind rich
silt. This silt provides excellent fertilizer for
crops. Even if the land is over-farmed and all the
nutrients are depleted from the soil, the land renews its fertility when new deposits of silt arrive following the next flood. Flood-control projects in the region, such as
levees, may increase human comfort but cause substantial adverse impact to the quantity and quality of arable land.
Non-arable land
Land which is unsuitable for arable farming usually has at least one of the following deficiencies: no source of fresh water; too hot (desert); too cold (Arctic); too rocky; too mountainous; too salty; too rainy; too snowy; too polluted; or too nutrient poor. Clouds may block the sunlight plants need for
photosynthesis (making sunlight into food), reducing productivity. Plants can starve without light.
Starvation and
nomadism often exists on marginally arable land. Non-arable land is sometimes called
wasteland,
badlands,
worthless or
no man's land.
However, non-arable land can be converted into arable land. New arable land makes more food, and can reduce
starvation. This outcome also makes a country more
self-sufficient and politically independent, because food importation is reduced. Making non-arable land arable often involves digging new irrigation canals and new wells, aqueducts,
desalination plants, planting trees for shade in the desert,
hydroponics, fertilizer, nitrogen fertilizer,
pesticides,
reverse osmosis water processors,
PET film insulation or other insulation against heat and cold, digging ditches and hills for protection against the wind, and greenhouses with internal light and heat for protection against the cold outside and to provide light in cloudy areas. This process is often extremely expensive.
Some examples of infertile
non-arable land being turned into fertile
arable land are:
- Aran Islands: This island off the west coast of Ireland, (not to be confused with the Isle of Arran in Scotland's Firth of Clyde), was unsuitable for arable farming because it was too rocky. The people covered the island with a shallow layer of seaweed and sand from the ocean. This made it arable. Today, crops are grown there.
- Israel: Israel's land primarily consisted of desert until the construction of desalination plants along the country's coast. The desalination plants, which remove the salt from ocean water, have created a new source of water for farming, drinking, and washing.
- Slash and burn agriculture uses nutrients in wood ash, but these expire within a few years.
Some examples of fertile
arable land being turned into infertile land are:
Droughts like the 'dust bowl' of the Great Depression in the U.S. turned farmland into desert.
Rainforest Deforestation: The fertile tropical forests turn into infertile desert land. For example, Madagascar's central highland plateau has become virtually totally barren (about ten percent of the country), as a result of slash-and-burn deforestation, an element of shifting cultivation practiced by many natives.
Romans' destruction of Carthage: At the end of the Punic Wars, legend has it that the victorious Romans sowed the earth with salt, to symbolize total victory. The Roman symbol meant that Carthage would never grow back - their civilization ended. (Whether this actually happened is debatable due to the logistics involved. Salt was very valuable and was used as money at the time, and it would have taken a lot of salt to ruin the whole area. See Carthage for details.) Most crops don't grow in highly saline soil. Consequently, salt water can't be used to water crops.
Each year, arable land is lost to desertification and erosion from human industrial activities. Improper irrigation of farm land can wick the sodium, calcium, and magnesium from the soil and water to the surface. This process steadily concentrates salt in the root zone, decreasing productivity for crops that are not salt-tolerant.
Urban sprawl: In the United States, 8,900 km² (about 2.2 million acres) of land was added to urban areas between 1992 and 2002.Further Information
Get more info on 'Arable Land'.
|
External Link Exchanges
Do you know how hard it is to get a link from a large encyclopaedia? Well we're different and will prove it. To get a link from us just add the following HTML to your site on a relevant page:
<a href="http://arable_land.totallyexplained.com">Arable land Totally Explained</a>
Then simply click through this link from your web page. Our crawlers will verify your link, extract the title of your web page and instantly add a link back to it. If you like you can remove the words Totally Explained and embed the link in article text.
As long as your link remains in place, we'll keep our link to you right here. Please play fair - our crawlers are watching. Your site must be closely related to this one's topic. Any kind of spamming, dubious practises or removing the link will result in your link from us being dropped and, potentially, your whole site being banned. |