2023年全國(guó)碩士研究生考試考研英語一試題真題(含答案詳解+作文范文)_第1頁
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1、華北水利水電學(xué)院碩士學(xué)位論文黃土地區(qū)土壤侵蝕特征及生態(tài)修復(fù)研究姓名:李艷麗申請(qǐng)學(xué)位級(jí)別:碩士專業(yè):水土保持與荒漠化防治指導(dǎo)教師:李永樂2011-05華北水利水電學(xué)院碩士學(xué)位論文 II SOIL EROSION CHARACTERISTICS AND ECOLOGICAL RESTORATION RESEARCH OF LOESS AREA ABSTRACT In recent decades,p

2、opulation increased dramatically,social economic development and high strength development of resources bring ecological degradation which becoming a global problem and constitudes a serious threat for human survival and

3、 sustainable development.How to protect existing natural ecosystems, comprehensive regulation and repair degenerate decosystems , and reconstruction sustainable artificial ecosystem have become urgently to be solved

4、before on human. Loess area as the most serious one of the soil and water loss areas in the world,its ecological system severely damaged,and recovery and reconstruction loess areas damaged ecosystem is the urgent task f

5、acing us in present. In order to curb the trend of ecological degradation in loess area,in many yreas,the county developed with a small watershed as a unit Comprehensive harness of soil and water conservation work and ha

6、ve achieved some results . This paper studies the classification of loess region, describes the characteristics of loess landform and physiognomy,classification of the loess landforms,divided into four kind which are mou

7、ntain landform classes, hills landform class, loess tableland landform class and Valley of plain landform.This paper research loess features and loess stratigraphic classification and distribution ,also divisional the lo

8、ess area according to climate, divided into five north temperate zones as climate warm temperate zone, south and north subtropical, warm temperate zone, the edge of the Tibetan plateau. Additional, it carried on the deta

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