首页
登录
职称英语
Every geologist is familiar with the erosion cycle. No sooner has an area of
Every geologist is familiar with the erosion cycle. No sooner has an area of
游客
2025-04-17
35
管理
问题
Every geologist is familiar with the erosion cycle. No sooner has an area of land been raised alive sea-level than it becomes subject to the erosive forces of nature. The rain beats down on the ground and washed【51】the finer particles, sweeping them into rivulets and then into rivers and out to sea. The frost freezes the rain water in cracks of the rocks and breaks【52】even the hardest of the constituents of the earth’s crust. Blocks of rock dislodged at high levels are brought down by the force of gravity. Alternate heating and【53】of bare rock surfaces causes their disintegration. In the dry regions of the world the wind is a powerful force in removing material from one area to another. All this is natural. But nature has also provided certain defensive forces. Bare rock surfaces are in【54】course protected by soil itself dependent initially on the weathering of the rocks. Slowly【55】surely, different types of soil with differing "profiles" evolve the main types depending primarily on the climate. The protective soil covering, once it is formed, is held together by the growth of vegetation. Grass and herbaceous plants,【56】long, branching tenuous roots, hold firmly together the surface particles. The【57】is true with the forest cover. The heaviest tropical down- pours beating on the leave of the giant trees reach the ground only【58】spray, gently watering the surface layers and penetrating along the long passages provided by the roots to the lower levels of the soil. The soil, thus protected by grass, herb, or trees, furnishes a quiet habitat for a myriad varied organisms-earth-worms that importantly modify the soil, bacteria, active in their work of converting【59】leaves and decaying vegetation into humus and food for the growing plants. Chemical action is constantly taking【60】. Soil acids attack mineral particles and salts in solution move from one layer in the soil to another. [br]
选项
答案
breaking
解析
与前文的breaks down呼应。
转载请注明原文地址:https://tihaiku.com/zcyy/4041168.html
相关试题推荐
ThefamiliarsoundsofanearlyEnglishsummerarewithusonceagain.Milli
ThefamiliarsoundsofanearlyEnglishsummerarewithusonceagain.Milli
ThefamiliarsoundsofanearlyEnglishsummerarewithusonceagain.Milli
Suchchanges,AcombinedwiththeerosionofBthearea’sbarrierislands,andthe
Ababymightshowfearofanunfamiliaradult,______heislikelytosmileandre
______herealizeditwasalreadytoolateforustoreturnhome.A、Nosooneritg
Everygeologistisfamiliarwiththeerosioncycle.Nosoonerhasanareaof
Everygeologistisfamiliarwiththeerosioncycle.Nosoonerhasanareaof
Everygeologistisfamiliarwiththeerosioncycle.Nosoonerhasanareaof
Everygeologistisfamiliarwiththeerosioncycle.Nosoonerhasanareaof
随机试题
Today’sworkerisnolongerwillingtoworkinanauthoritariananddehumani
StudentA:Ifeelsick.StudentB:______StudentA:I’mnotsure,butIhavegot
如何才能以100%的比例显示图象:
大黄止血的作用环节是A.促进血小板的解聚功能B.扩张局部血管C.降低抗凝血酶Ⅲ活
极性最大的溶剂是A.丁醇 B.苯 C.甲醇 D.水 E.丙酮
墨菲法则:如果某件事有可能变坏的话,这种可能就会成为现实;它的适用范围非常广泛,
阅读下列材料。回答问题。 ①来时。便听说台北是个多雨的城市,尤其是冬季,雨下得
基础心理学是研究()。 (A)正常成人心理现象的心理学基础学科 (B
对模拟声音信号的采样频率越高,声音的保真度越好。根据采样定理,在对模拟声音信号采
患者男,10岁。右足底被铁锈钉刺伤10天,突然出现张口困难,继之出现苦笑面容,角
最新回复
(
0
)