根据以下材料，回答1-20题 The livestock's outsize impacts have become m
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根据以下材料，回答1-20题
The livestock's outsize impacts have become more prominent in environmental 1 lately and for good reason. Beef and dairy are 2 for more greenhouse gas emissions than any other food source by a long shot, largely 3 methane from cattle's digestion, emissions from manure, and the 4 of carbon-rich forest to pasture and cropland for animal feed.
While the development of meat and dairy 5 ,such as plant-based meat, is helping shift diets in rich countries, the world is still 6 more beef and milk every year.As emerging economies grow, we can expect their beef consumption to follow in 7 . While this increase signals that more people are able to afford richer, more varied diets, it 8 grim prospects for the climate.But there's a 9 story as well—one that is underappreciated and provides hope that livestock's impact can be reduced: the story of peak pasture.
In the past 20 years,something 10 has occurred, something few predicted: after several centuries of expansion, global pasture area has begun to 11 . According to the United Nations' most recent data, there are a 12 140 million fewer hectares of pasture than there were in 2000, an area roughly the size of Peru.Because pasture is one of the largest 13 of deforestation in many regions—and of the habitat loss and carbon 14 that follow—this is good news for the environment.
This positive trend has a strikingly simple explanation: rising 15 of pasture land and livestock.Thanks to modern breeding efforts and more resource-efficient 16 , the world is producing a greater 17 of meat and milk than ever before, even as pasture area has shrunk.Average global beef production per cow, for instance,has grown about 30 percent since 1961, and land managers across continents have begun growing specific grasses for cattle to eat that can 18 production severalfold.
Analogous to the green revolution of the 20th century that brought unprecedented levels of crop productivity, it's fair to say that the world has undergone a "livestock revolution"—not the whole world, however.Most notably, productivity remains low in sub-Saharan Africa, where widespread overgrazing 19 the quality of grazing land.Rapid population and economic growth in the region, 20 persistently low productivity, could augur a major re-expansion of global pasture.
第19题答案是
