2. 考研
  3. Until about four decades ago, crop yields in agricultural systems depended on (1)_____ resources, recycling organic matter, buil

Until about four decades ago, crop yields in agricultural systems depended on (1)_____ resources, recycling organic matter, buil

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问题     Until about four decades ago, crop yields in agricultural systems depended on (1)_____ resources, recycling organic matter, built-in biological control mechanisms and rainfall patterns. Agricultural yields were (2)_____ but stable. Production was (3)_____ by growing more than one crop or variety in space and time in a field as insurance against pest (4)_____ or severe weather. Inputs of nitrogen were (5)_____ by rotating major field crops with legumes. In turn, rotations suppressed insects, weeds and diseases by effectively (6)_____ the life cycles of these pests. A typical corn belt farmer grew corn (7)_____ with several crops including soybeans, and small grain production was intrinsic to maintain livestock. Most of the labor was done by the family with occasional hired help and no (8)_____ equipment or services were purchased from off4arm sources. In these type of farming systems the link between agriculture and ecology was quite (9)_____ and signs of environment degradation were seldom evident.
    But as agriculture modernization (10)_____ the ecology-farming linkage was often broken as ecological principles were (11)_____. In fact, several agricultural scientists have arrived at a (12)_____ consensus that modem agriculture confronts an environment crisis. A growing number of people have become concerned about the long-term (13)_____ of existing food production systems. Evidence has shown that (14)_____ the present capital-and-technology-intensive fanning systems have been extremely productive and competitive, they also bring a (15)_____ of economic, environmental and social problems.
    Evidence also shows that the very nature of the agricultural structure and prevailing polices have led to this environmental (16)_____ by favoring large farm size, specialized production, crop monocultures and mechanization. Today as more and more farmers are integrated (17)_____ international economies, imperatives to (18)_____ disappear and monocultures are rewarded by economies of scale. In turn, lack of rotations and diversification (19)_____ key self-regulating mechanisms, turning monocultures into highly (20)_____ agro-ecosystems dependent on high chemical inputs.

选项 A、with
B、to
C、at
D、into
答案D
解析 考查上下文语义衔接和固定搭配。integrate with是"使二者融合"的意思，integrate into是固定短语"使融入"的意思，这里是说越来越多的农民融入到国际经济中，因此选into；但是integrate不与to和at连用。
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考研英语一

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