All this means that agriculture in the 21st century will have to be very different from how it was in the 20th.this will require radical thinking.for example,we need to move away from the idea that traditional practices are inevitably more sustainable than new ones.we also need to abandon the notion that agriculture can be “zero impact”. The key will be to abandon the rather simple and static measures of sustainability,which centre on the need to maintain production without increasing damage.instead we need a more dynamic interpretation,one that looks at the pros and cons of all the various way land is used.there are many different ways to measure agricultural performance besides food yield:energy use, environmental costs,water purity,carbon footprint and biodiversity. It is clear, for example,that the carbon of transporting tomatoes from spain to the UK
Is less than that of producing them in the UK with additional heating and lighting.but we do not know whether lower carbon footprints will always be better for biodiversity.
What is crucial is recognizing that sustainable agriculture is not just about sustainable food production.
52. How do people ofen measure progress in agriculture?
A) By its productivity C) By its impact on the environmet
B) By its sustainability D) By its contribution to economic growth
53. Specialisation and the effort to incease yields have esulted in________.
A) Localised pollution C) competition from overseas
B) the shrinking of farmland D) the decrease of biodiversity
54.What does the author think of traditional farming practices?
A)They have remained the same over the centuries
B)They have not kept pace with population growth
C)They are not necessarily sustainable
D)They are environmentally friendly
55.What will agriculture be like in the 21st century
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