Why is the amount of arable land decreasing?

Question

I read about how the soil of tropical rainforests cannnot sustain intensive farming since they are not as fertile as arable land. It suggests that instead we should now maximise yields on existing arable land instead of clearing tropical rainforests. I would like to ask why can arable land sustain agriculture for so long since the soil has been cleared of its trees anyway and decomposition no longer occurs as frequently which makes the soil degenerate eventually too. Therefore why is it suggested that we should maximise on existing arable lands since by logic they will like the not very fertile soils of tropical rainforest eventually degenerate unless arable land can somehow regenerate nutrients which tropical rainforest soil cannot.

Answer 1

Tropical rainforests typically have a soil called a laterite. It is stipped of most minerals and is composed primarily of iron oxides. Plants require many minerals for health so typically, a jungle soil can only provide one or two crops before it is no longer useful. With modern fertizers, farmers can sustain soils indefinitely. Typically, the rain forests might be farmed in a slash and burn by very poor people without sufficient resourses and no ownership of the land. Without ownership, there is little incentive to keep the land productive over the long time span.

Answer 2

With propermanagement arable land can remain productive indefinitely.

With respect to trpical rain forest, again with proper management that land can remain productive indefinitely.

The problem has balways been proper management.

Many farmers, particularly in very poor countries do not know how to manage the soil on their farms.

In many cases the vaue of the crops is so low that the farmers do not have the money to manage the soil on their farms properly.

In the United States we have Agricultutal colleges and agricultural extension programs designed to teach farmers how to better manage their farms and the soil on their farms.

We need to do the same throughout the world, particularly in very poor areas where farmers do not have the resources or the education to manage their farms properly.

Answer 3

I question that the amount of arable land is decreasing in the world. One problem is that the word "arable" is not really defined precisely, so an area of land might be classified as arable in one survey and not arable in another.

Answer 4

arable land is not decreasing. the water to use is decreasing.
big cities are taking the water that used to be used on arable land

Answer 5

It's a very good question you ask. I recommend the book, "Collapse: How Societies Choose to Fail or Succeed" by Jared Diamond.

Answer 6

because the u.s. government owns too much of it,think of all of the streets that we don't need