soil erosion in bolivia cherry. what is soil erosion? soil may be detached and moved by water, wind...
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Soil Erosion in BoliviaCherry
What is soil erosion?Soil may be detached and moved by water, wind or tillage.
Water ErosionSoil erosion by water is the result of rain detaching and transporting vulnerable soil, either directly by means of rainsplash or indirectly by river and gully erosion.
Wind ErosionSoil erosion by wind may occur wherever dry, sandy or dusty surfaces, inadequately protected by vegetation, are exposed to strong winds. Erosion involves the picking up and blowing away of loose fine grained material within the soil. Damage from wind erosion is of numerous types.
Tillage Erosion Tillage erosion results in loss as a result of tilling or working the soil on slopes and exposing it to the elements. Plowing is particularly harmful. Organic material is swept away by wind and rain leaving the soil less productive and with poorer texture.
Soil Erosion in Bolivia
Almost 45% of Bolivias 1 098 000 hectares is forestland, covering and lying in the departments of Beni, Pando, Santa Cruz and the tropical parts of Cochabamba and La Paz.
The loss of this vegetation began a process of erosion of fertile topsoil that continues to the present day. Bolivia is especially vulnerable to soil erosion because of the steep mountainous nature of the land.
Without vegetation to slow run-off, absorb excess water, and hold the soil together, large amounts of fertile topsoil continue to be lost to erosion. More recent causes of soil erosion have been overgrazing, poor cultivation methods, and mining.
Population pressure is also a contributing factors, the substantial number of Bolivians who live in the highlands are by necessity using the same limited supplies of wood for cooking and clearing the same fragile land for agricultural farming.
1. Removal of the vegetation cover. This means that no further humus is added to nourish the soil and there are no roots to bind the soil together. If the surface is exposed to wind and rain, the soil will be carried away leaving deep gullies or bare rock
2. Poor arable farming methods lead to soil damage. Overcultivation, especially with one crop, cotton in the U.S.A., impoverishes the soil. With this, the soil is not allowed time to 'rest' and restore itself naturally and eventually crops can no longer grow in the soil and the bare soil is eroded.. Farmers find it easier to plough down a slope than across it. When it rains, water flows down the furrows and washes away the soil creating gullies.Irrigation, the artificial application of water to the land, can result in salinity.What cause it?
3. Poor pastoral farming methods lead to soil damage. Sometimes, too many animals are kept in one area and they eat the vegetation until it becomes too short and dies off (this is called overgrazing). Wind and rain can then remove the bare soil.
4. Urbanisation, highway construction and industry tend to consume vast areas of our most fertile farmland. Extractive (primary ) industry tends to be very destructive with quarries, mines and waste tips.
Why important?Soil erosion leads to desertification. Desertification refers to increase of desert areas.
Soil erosion results in the loss of soil fertility and makes the land barren. There are more than 25 million hectares of barren lands in the world now.
Why important?inflence agriculture and cause the shortage of the food.
A river erodes farmland, or ocean waves cut away shoreline.
HARM!changing of the landscape
The loss of topsoil affects plant growth. When people do not have enough food crops, they will have less to eat and their health will suffer.
What's more?Only 30% of the planet's surface is land and only 11% of this land surface is good agricultural land. It is estimated to take over 3,000 years to form a good agricultural soil and yet we will have destroyed over 30% of our good farmland by the year 2,000. This erosion is most severe where the land is misused and the climate is extreme.
DesertificationLA PAZ - Over 40 percent of the Bolivian territory is affected by desertification caused by climate change, population increase and indiscriminate forest felling.
The desertification in Bolivia affects 41 percent of the national territory, 439,432 square km, where 77 percent of the national inhabitants live, some 6.4 million people.
As much as 89 percent of Bolivians living in the affected territory are in extreme poverty.
The country loses 1.8 million tons of different agriculture products each year owing to soil erosion, according to scientific research.
To the futureThe erosion of arid, semi-arid and other climate zones affects seven of the nine departments in this South American country, and extends across some 495,000 square km of Bolivia's territory of 1.98 million square km.Become desert for more than half of the country.
Lack of food casue the lack of food.
How to solve that?Solving soil erosion problems, in Bolivia and elsewhere, is a monumental task.
There are no simple, clear cut solutions. A mix of human activity, hard work, and grassroots organization are necessary if we are ever to see some improvements in the future.
1. Prevent erosion of soil, it is important to maintain a vegetation cover, especially in the most vulnerable areas e.g. those with steep slopes, a dry season or periods of very heavy rainfall. To do this may mean only partially harvesting forests and using seasonally dry or wet areas for pastoral rather than arable agriculture.
2. In order to prevent the soil becoming exhausted. Where soils are ploughed in vulnerable areas, contour ploughing.
3.Careful management of irrigation, to prevent the application of too much or too little water, should help reduce the problem of salination.
4. livestock grazing rates must be carefully managed to prevent overgrazing.
5. Attempt to restrict highway construction and urbanisation to areas of lower agricultural potential.