How can farming lead to desertification? What might be done to prevent it?

Question

How can farming lead to desertification? What might be done to prevent it?

Answer 1

One of the major problems with large scale agriculture is that it is based on and requires a physical manipulation of the soil to remove surface vegetation in an attempt to give a clear field and to lighten the compaction of mechanical equipment used in modern farming. The plow, harrows, and other mechanical devices break up and turn the soil roughly, followed by other equipment to prepare a finer seed bed or field planting rows. Over the course of season after season, the mechanical breaking and raking of the soil starts to break up the soil structure where it becomes finer and finer. Natural un-plowed soils have a structure that, over the course of millions of years, plants have adapted to for their growing needs. At first these nice fields seem a wonderland for production; clear and free of growth, ready to accept our crop. But that same soil structure begins to loose its pore structure, that of macro pores and smaller micro pores which allow for the movement of water and the replacement/ changing of gases (oxygen is vital to roots just as to leaves). There is a lower population of important soil organisms as they are destroyed by the mechanical action and the populations left are not nurtured by chemical applications (they are further reduced in population). With the soil now turned up and mechanically pulverized the wind will blow the dried surface away which is the clay and light humus. Also the unprotected soil can now be eroded by rain, washing the same materials into the river. If the only amendments to the soil are chemical fertilizer and pesticides there is no replacement of organic components. If the only other possible materials added are coarse vegetable products in low quantity, it is too little too late. This was the beginning of the end in the early 1900's America; the dust bowl years. These poor practices with the wind and drought conditions caused exactly this problem, that of desertification or the beginnings of it in a lot of areas. It happened also in the old Roman empire though it took longer. So much production to support the empire, even without the heavy metal monsters of our day turned marginally productive areas to ruined land with farm practices that were not understood in long term respect.

To fight the trends, one must sacrifice the plow and machine in the mega farm and adopt sustainable agricultural practices as well as good organic principals. We must mimic nature in all respects of the land will suffer. Plants are, by evolution, designed to grow in a certain way. Monoculture is not natural and disease issues follow. Plowing is not natural and desertification follows. Chemicals are not natural and pollution/ toxic food follows. No-till methods keep the soil and the life of the soil invigorated and better than it was. Companion plantings and resting a field alleviates problems frequented by mono cultural practices. Organic amendments protect the land the water and the environment by assuring no toxins are introduced. Management techniques address issues before a problem is out of hand. Integrated pest management is one of those that most are aware of. The short answer is to consider the land and use what we have learned, accepting that more money now for a sloppy job is just not in the interests of the people for more than the short time we are here. There will always be those who will go for the gold without care and claim they are trying to feed the people, and that caring for the land will not feed them all, that all this about "hugging the land" is bull. Those are the people who have a stake in making their money before the land is broken, then they retire and die, what do they care. I would think that by caring now and doing what is right will keep them from having to get the government involved with more regulations as the problem deepens. Even the high priced lobbyists won't help much then. This has been a sore spot for years with a lot of people and defiantly generates a lot of response and bad feelings with some. But if you are not right, you are just not right and no amount of anger and crying and mitigating circumstance will make it right. All the talk of "You'll pay more for your food will wash, especially when our imports and exports tell us "It's not anything but manipulation of money into some one persons pocket at the expense of all the others. And that, is desertification.

Answer 2

Removal of trees will also lend to desertification, as the water table and salinity levels change. In many places, trees are removed to make way for farms.

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Answer 3

How can farming lead to desertification?

Whenever farming is intensive on lands it abuses the land. Today's farmers use lots of chemicals-i.e., pesticides, inceticides, fertilizers-to improve crop yields. These chemicals are harmful to the environment. They leach down into the soil, contaminate it, run-off into streams, rivers, and lakes. The chemicals kill fish, other marine animals and helpful algies in water. Extensive use of these chemicals in modern agriculture is causing severe and sometimes irriversible damage to the environment.

What might be done to prevent it?

1. Crop rotation from one parcel of land to another can help

2. Planting alfalfa adds nitrogen and other nutrients to the soil

3. Plowing biomass (example: corn stalks, cabbage waste, pumpkin waste, compost leaves, cow manure, horse manure, etc.) helps add nutrients to the soil

4. Keeping the land follow for 7 years then producing on it for 7 years rejuvinates the land

5. Eliminate the use of chemicals on the land help preserve it for future generations.

Answer 4

Most areas in the world experiencing desertification are arid, grazed lands, not row cropped land.  In these areas, overgrazing is the primary cause with goats being the primary culprit because goats eat and kill brush and shrubs while cattle and wool sheep normally don't.  In many of the African areas experiencing the problem, their culture is also part of the problem.  Animals are considered wealth and the more animals you have, the wealthier you are.  Depopulating the flock is the answer to desertification but the people refuse to do so, and therefore are sealing their own fate.  

In short, it's not agricultural activities such as cropping and grazing that cause desertfication, it's the people who carry on those practices andn their refusal to change that do.

Answer 5

over cultivation will lose the land's productivity

Answer 6

Planting the same crops year after year can literally suck the life out of the soil and lead to very few things being able to grow in it.  Also wind exposure can blow away the topsoil (google the Dust Bowl in the usa in the 30s for more info).

As to how to prevent such things; crop rotation, so that the soil can be allowed to recover, and not get the same nutrients sucked out year after year.  Also wind breaks are a good idea, like hedgerows for instance on field borders.

Answer 7

We do not see desertification unless we have very low rainfall, so first this does not happen because someone in a rice paddy grows rice every year for several centuries.

Intensive agriculture in areas with good rainfall do not become deserts, regardless or cropping patterns.

Tilling soil ans so exposing it to wind erosion is a major contributor, so that no-till agriculture, often maintained with use of herbicides is a great strategy. Leaving a strip of shrubbery can capture any wind erosion that starts, but planting  a row of trees is mostly useful while there is enough rainfall to support that growth of trees, even before they become well established.

Once it becomes impractical to plant and maintain a row of trees, we have to switch from farming to ranching to be sure, and then be very careful of overgrazing damage.

In near desert, we have to ask whether farming is viable, whether ranching is viable, and  avoid doing either except on a nomadic basis.