Desertification in the arid United States is flagrant. Groundwater supplies beneath vast stretches of land are dropping precipitously. Whole river systems have dried up; others are choked with sediment washed from denuded land. Hundreds of thousands of acres of previously irrigated cropland have been abandoned to wind or weeds. Several million acres of natural grassland are eroding at unnaturally high rates as a result of cultivation or overgrazing. All told, about 225 million acres of land are undergoing severe desertification.
Federal subsidies encourage the exploitation of arid land resources. Lowinterest loans for irrigation and other water delivery systems encourage farmers, industry, and municipalities to mine groundwater. Federal disaster relief and commodity programs encourage aridland farmers to plow up natural grassland to plant crops such as wheat and, especially, cotton. Federal grazing fees that are well below the free-market price encourage overgrazing of the commons. The market, too, provides powerful incentives to exploit arid land resources beyond their carrying capacity. When commodity prices are high relative to the farmer’s or rancher’s operating costs, the return on a productionenhancing investment is invariably greater than the return on a conservation investment. And when commodity prices are relatively low, arid land ranchers and farmers often have to use all of their available financial resources to stay solvent.
The incentives to exploit arid land resources are greater today than ever. The government is now offering huge new subsidies to produce synfuel from coal or oil shale as well as alcohol fuel from crops. Moreover, commodity prices are on the rise; and they will provide farmers and agribusiness with powerful incentive to overexploit arid land resources. The existing federal government costshare programs designed to help finance the conservation of soil, water, and vegetation pale in comparison to such incentives.
In the final analysis, when viewed in the national perspective, the effects on agriculture are the most troublesome aspect of desertification in the United States, for it comes at a time when we are losing over a million acres of rain-watered crop and pasture land per year to “higher uses”— shopping centers, industrial parks, housing developments, and waste dumps— heedless of the economic need of the United States to export agricultural products or of the world’s need for U.S. food and fiber. Today the arid West accounts for 20% of the nation’s total agricultural output. If the United States is, as it appears, well on its way toward overdrawing the arid land resources, then the policy choice is simply to pay now for the appropriate remedies or pay far more later, when productive benefits from arid land resources have been both realized and largely terminated.
1. The author is primarily concerned with
(A) discussing a solution
(B) describing a problem
(C) replying to a detractor
(D) finding a contradiction
(E) defining a term
2. The passage mentions all of the following as effects of desertification EXCEPT
(A) increased sediment in rivers
(B) erosion of land
(C) overcultivation of arid land
(D) decreasing groundwater supplies
(E) loss of land to wind or weeds
3. The author most likely encloses the phrase “higher uses” (Highlighted) in quotations marks in order to
(A) alert the reader to the fact that the term is very important
(B) minimize the importance of desertification in non-arid land
(C) voice his support for expansion of such programs
(D) express concern over the extent of desertification
(E) indicate disagreement that such uses are more important
4. The passages mentions all of the following as economic factors tending to contribute to desertification EXCEPT
(A) price incentives for farmers to use arid lands to produce certain commodities
(B) artifically low government fees for use of public grazing lands
(C) government subsidies for fuels that are manufactured from a variety of crops
(D) worldwide demand for the food and fiber produced in the United States
(E) lack of effective government financial incentives to conserve soil, water, and vegetation
5. According to the passage, the most serious long-term effect of desertification would be the reduced ability of
(A) the United States to continue to export agricultural products
(B) municipalities to supply water to meet the needs of residents
(C) farmers to cover the cost of producing crops
(D) the United States to meet the food needs of its own people
(E) the United States to produce sufficient fuel for energy from domestic sources
6. The passage leads most logically to discussion of a proposal for
(A) reduced agricultural output in the United States
(B) direct government aid to farmers affected by desertification
(C) curtailing the conversion of land to shopping centers and housing
(D) government assistance to develop improved farming methods to increase exploitation of arid land
(E) increased government assistance to finance the conservation of arid land
7. The author’s attitude toward desertification can best be described as one of
(A) alarm
(B) optimism
(C) understanding
(D) conciliation
(E) concern
参考答案：
esertification的原因——干旱土地开发的鼓励政策