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The average population density of the world is 47 persons per square mile. Continental densities range from no permanent inhabit
The average population density of the world is 47 persons per square mile. Continental densities range from no permanent inhabit
admin
2013-01-15
57
问题
The average population density of the world is 47 persons per square mile. Continental densities range from no permanent inhabitants in Antarctica to 211 per square mile in Europe. In the western hemisphere, population densities range from about 4 per square mile in Canada to 675 per square mile in Puerto Rico. In Europe the range is from 4 per square mile in Iceland to 831 per square mile in the Netherlands. Within countries there are wide variations of population densities. For example, in Egypt, the average is 55 persons per square mile, but 1,300 persons inhabit each square mile in settled portions where the land is arable.
High population densities generally occur in regions of developed industrialization, such as the Netherlands, Belgium, and Great Britain, or where lands are intensively used for agriculture, as in Puerto Rico and Java.
Low average population densities are characteristic of most underdeveloped countries. Low density of population is generally associated with a relatively low percentage of cultivated land. This generally results from poor-quality lands. It may also be due to natural obstacles to cultivation, such as deserts, mountains or malaria-infested jungles, to land uses other than cultivation, as pasture and forested land, to primitive methods that limit cultivation, to social obstacles, and to land ownership systems which keep land out of production.
More economically advanced countries of low population density have, as a rule, large proportions of their populations living in urban areas. Their rural population densities are usually very low. Poorer developed countries of correspondingly low general population density, on the other hand, often have a concentration of rural population living on arable land, which is as great as the rural concentration found in the most densely populated industrial countries.
In timberland areas of the world, ______.
选项
A、there is dense population
B、we may expect to find malaria-infested jungles
C、the density of population is relatively low
D、good quality land is found
答案
C
解析
在世界上的林区,人口密度很低。作者在第三段说,人口密度低往往与可耕地面积的比例不高有一定的联系。人口密度低一般是由于土地贫瘠造成的,也有可能是由不利于耕种的天然障碍造成的,如沙漠、山区或疟疾肆虐的丛林。
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