共用题干Egypt Felled by FamineEven ancient Egypt's mighty pyramid builders were powerless in the face of the famine that helped bring down their civilization around 2180 BC.Now evidence gleaned（搜集）from mud deposited by the River Nile suggests that a shift in climate thousands of kilometers to the south was ultimately to blame-and the same or worse could happen today.The ancient Egyptians depended on the Nile's annual floods to irrigate their crops.But any change in climate that pushed the African monsoons（季风）southwards out of Ethiopia would have diminished these floods.Dwindling（使减少）rains in the Ethiopian highlands would have meant fewer plants to establish the soil.When rain did fall it would have washed large amounts of soil into the Blue Nile and into Egypt,along with sediment（沉积物）from the White Nile.The Blue Nile mud has a different isotope（同位素）signature from that of the White Nile.So by analyzing isotope differences in mud deposited in the Nile Delta,Michael Krom of Leeds University worked out what proportion of sediment came from each branch of the river.Krom reasons that during periods of drought,the amount of the Blue Nile mud in the river would be relatively high.He found that one of these periods,from 4,500 to 4,200 years ago,immediately predated the fall of the Egypt's old Kingdom.The weakened waters would have been catastrophic for the Egyptians."Changes that affect food supply don't have to be very large to have a ripple effect in societies,"says Bill Ryan of the Lamont Doherty Earth Observatory（天文台）in New York."Similar events today coald be even more devastating,"says team member Daniel Stanley,a geoarchaeologist from the Smithsonian Institution in Washington, D.0."Anything humans do to shift the climate belts woulld have an even worse effect along the Nile system because the populations have increased dramatically."According to Krom,Egypt's Old Kingdom fell______.A:immediately after a period of droughtB:immediately after a period of floodC:just before a drought struck D:just before a flood struck
共用题干
Egypt Felled by Famine
Even ancient Egypt's mighty pyramid builders were powerless in the face of the famine that helped bring down their civilization around 2180 BC.Now evidence gleaned（搜集）from mud deposited by the River Nile suggests that a shift in climate thousands of kilometers to the south was ultimately to blame-and the same or worse could happen today.
The ancient Egyptians depended on the Nile's annual floods to irrigate their crops.But any change in climate that pushed the African monsoons（季风）southwards out of Ethiopia would have diminished these floods.
Dwindling（使减少）rains in the Ethiopian highlands would have meant fewer plants to establish the soil.When rain did fall it would have washed large amounts of soil into the Blue Nile and into Egypt,along with sediment（沉积物）from the White Nile.
The Blue Nile mud has a different isotope（同位素）signature from that of the White Nile.So by analyzing isotope differences in mud deposited in the Nile Delta,Michael Krom of Leeds University worked out what proportion of sediment came from each branch of the river.
Krom reasons that during periods of drought,the amount of the Blue Nile mud in the river would be relatively high.He found that one of these periods,from 4,500 to 4,200 years ago,immediately predated the fall of the Egypt's old Kingdom.
The weakened waters would have been catastrophic for the Egyptians."Changes that affect food supply don't have to be very large to have a ripple effect in societies,"says Bill Ryan of the Lamont Doherty Earth Observatory（天文台）in New York.
"Similar events today coald be even more devastating,"says team member Daniel Stanley,a geoarchaeologist from the Smithsonian Institution in Washington, D.0."Anything humans do to shift the climate belts woulld have an even worse effect along the Nile system because the populations have increased dramatically."
Egypt Felled by Famine
Even ancient Egypt's mighty pyramid builders were powerless in the face of the famine that helped bring down their civilization around 2180 BC.Now evidence gleaned（搜集）from mud deposited by the River Nile suggests that a shift in climate thousands of kilometers to the south was ultimately to blame-and the same or worse could happen today.
The ancient Egyptians depended on the Nile's annual floods to irrigate their crops.But any change in climate that pushed the African monsoons（季风）southwards out of Ethiopia would have diminished these floods.
Dwindling（使减少）rains in the Ethiopian highlands would have meant fewer plants to establish the soil.When rain did fall it would have washed large amounts of soil into the Blue Nile and into Egypt,along with sediment（沉积物）from the White Nile.
The Blue Nile mud has a different isotope（同位素）signature from that of the White Nile.So by analyzing isotope differences in mud deposited in the Nile Delta,Michael Krom of Leeds University worked out what proportion of sediment came from each branch of the river.
Krom reasons that during periods of drought,the amount of the Blue Nile mud in the river would be relatively high.He found that one of these periods,from 4,500 to 4,200 years ago,immediately predated the fall of the Egypt's old Kingdom.
The weakened waters would have been catastrophic for the Egyptians."Changes that affect food supply don't have to be very large to have a ripple effect in societies,"says Bill Ryan of the Lamont Doherty Earth Observatory（天文台）in New York.
"Similar events today coald be even more devastating,"says team member Daniel Stanley,a geoarchaeologist from the Smithsonian Institution in Washington, D.0."Anything humans do to shift the climate belts woulld have an even worse effect along the Nile system because the populations have increased dramatically."
According to Krom,Egypt's Old Kingdom fell______.
A:immediately after a period of drought
B:immediately after a period of flood
C:just before a drought struck
D:just before a flood struck
A:immediately after a period of drought
B:immediately after a period of flood
C:just before a drought struck
D:just before a flood struck
参考解析
解析：第一段第一句表明，公元前2180年的饥荒使古埃及文明衰落，即使古埃及伟大的金字塔的建造者面对那场饥荒也无能为力。由此可知，作者提到金字塔的建造者，是为了表明即使是他们也无法拯救古埃及文明的衰落，故选D项。
第一段第二句提到，目前从尼罗河沉积的泥浆中收集的证据表明可将这次饥荒最终归咎于南面数千千米处发生的气候变化。因此气候变化是造成古埃及文明衰落的终极原因，而饥荒只是表层的因素，故选A项。
第四段表明，青尼罗河的泥浆与白尼罗河的泥浆中的同位素不同，通过分析尼罗河三角洲的泥浆中的同位素的差别，利兹大学的迈克尔.克罗姆算出了来自各个支流的沉淀物的比例。由此可知，青尼罗河和白尼罗河是尼罗河的支流，故选D项。
第五段表明，克罗姆发现4500年以前到4200年以前的干旱刚好发生在古埃及王国衰落之前。由此可以推断出，古埃及王国的衰落紧跟在一次旱灾之后，故选A项。
此处devastating为形容词，意思是“破坏性的”。frustrating令人沮丧的；damaging破坏的，毁坏的；defeating击败的；worrying令人担忧的，令人发愁的。各项中只有B项与devastating意义相近，故选B项。
第一段第二句提到，目前从尼罗河沉积的泥浆中收集的证据表明可将这次饥荒最终归咎于南面数千千米处发生的气候变化。因此气候变化是造成古埃及文明衰落的终极原因，而饥荒只是表层的因素，故选A项。
第四段表明，青尼罗河的泥浆与白尼罗河的泥浆中的同位素不同，通过分析尼罗河三角洲的泥浆中的同位素的差别，利兹大学的迈克尔.克罗姆算出了来自各个支流的沉淀物的比例。由此可知，青尼罗河和白尼罗河是尼罗河的支流，故选D项。
第五段表明，克罗姆发现4500年以前到4200年以前的干旱刚好发生在古埃及王国衰落之前。由此可以推断出，古埃及王国的衰落紧跟在一次旱灾之后，故选A项。
此处devastating为形容词，意思是“破坏性的”。frustrating令人沮丧的；damaging破坏的，毁坏的；defeating击败的；worrying令人担忧的，令人发愁的。各项中只有B项与devastating意义相近，故选B项。