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AN EXPERIMENTAL sTUDY OF sHEET EROsION IN GRANITIC REGION OF WUHUA COUNTY,GUANGDONG PROVINCE

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Journal of Geographical sciences 1994年第Z2期4卷 148-158页

作者： Jin Changxing(Institute of Geography, CAs, Bejing 100101 people’s republic of china)Zang Guohua(soil and Water conservation Experimental station of Wuhua, Guangdong 514471people’s republic of china)

The relationships between rainfall, runoff and erosion in south china granitic weathering red soil region were studied by using data collected from 7 experimental plots in Wuhua County, Guangdong Province. Results showed that when rainfall is less than 50 mm, small volumes of runoff were produced. Rainfall intensity might be the main factor in controlling runoff. When rainfall exceeds 50 mm, because of its large volume and high intensity, runoff and the produced amount of erosion increased with raimfall quickly. Analysis of the relationship bebeen runoff and erosion suggsted that runoff of 30 mm (corresponding to about 50 mm rainfall might be taken as a threshold at which wter on land surface was sufficient to start the larg amount of soil particles. Vegtation cover is very effective in protection soil from being eroded. When vegetation coverag increases from 0 to 80 percent,runoff and soil loss decrease from 179.34mm/a to 126.36mm/a and 6262.15T/a km2 to 368.02 T/a km2, respectively.

关键词： soil erosion experimental study south china

LAND DEGRADATION AND ITs CONTROL sTRATEGIEs IN china

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Journal of Geographical sciences 1997年第2期7卷 1-12页

作者： Yang Chaofei Dapartment of Natural conservation, National Environmental Protection Agency, Beijing 100035 people’s republic of china

Human induced land degradation refers to decline or loss of biological or economic productivity resulting from a process or combination of processes, including displacement of soil matreial, terrain deformation and loss of nutrients and/or orgnic matter through wind erosion, water erosion, secondary salinization and pollution. Wind erosion is a major problem in the dry land of china and the area of sandy desertified land caused by wind erosion has reached 371,000 km 2. Water erosion frequently occurs in hilly and mountainous areas where 1.79 million km 2 of land have been observed and degraded land area affected by secondary salinization now covers 63,000 km 2 in china. statistical data indicated that depletion of soil nutriution is a serious problem in china. some 460,000 km 2 of cultivated or 46 percent of the total cultivated land area is deficient in P, and 330,000 km 2 of cultivated land or one-third of nation′s total is deficient in K. Adverse human activities are recognized as a principal reason of land degradation. In northern china, 30.1 percent of land degradation caused by over grazing, 26.9 percent by over reclamation, 33.7 percent by excessive fuel collection, 9.6 percent by mis-use of water resources, as well as 0.7 percent by industrial, mining and transportation construction. In southern china, 37 percent of degraded land caused by deforestation, 35 percent by slopeland reclamation, 18 percent by improper afforestation, and 10 percent by industrial, mining and transportation construction. Following the discussion of the causes and disasters of land degradation, this paper presents the achievements gained in prevention and control of land degradation since 1949. The several control strategic measures in combating land degradation such as prompting public awareness and people's participation, strengthening national laws and policies formulation, carrying out projects on rehabilization and monitoring, are proposed by the end of this paper.

关键词： china land degradation current status causes disaster achievements strategies.

论影响子孙后代的历史性错误——长江变成黄河的严峻现实与反思

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水土保持学报 1988年第3期 1-7页

作者：李一功中华人民共和国林业部

根据长江中上游水土流失程度,长江变成黄河已是无可辩驳的事实;如果不立即防治,其后果比黄土高原严重得多。目前,光山秃岭迅猛发展,使几十万年形成的沃土变为不毛之地;旱灾和洪灾交替发生,滑坡和泥石流频繁而严重;淤浅水库和河床,妨碍... 详细信息

根据长江中上游水土流失程度,长江变成黄河已是无可辩驳的事实;如果不立即防治,其后果比黄土高原严重得多。目前,光山秃岭迅猛发展,使几十万年形成的沃土变为不毛之地;旱灾和洪灾交替发生,滑坡和泥石流频繁而严重;淤浅水库和河床,妨碍交通航运;广大人民生活贫困,部分灾民靠救济为生。综合治理,尽快改变现状,脱贫致富,希望很大。主要对策有:1、用生态经济的系统工程,治理长江中上游的水土流失;2、营造防护林体系工程,恢复和扩大以森林为主体的生态系统;3、抓住重点,培养样板;4、加强科学研究工作,充分发挥其先导作用。

关键词：水土流失地区无可辩驳水土流失区坡耕地长江年侵蚀模数小流域综合治理黄土高原黄河

spin-conserved PEs Calculation:First Application on 178Hf

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Spin-conserved PES Calculation:First Application on 178Hf

第十三届全国核结构研讨会暨第九次全国“核结构与量子力学”专题讨论会

作者： C.F.Jiao~1 F.R.Xu~(1 1)) Y.sun~2 1(school of Physics,and state Key Laboratory of Nuclear Physics and Technology,Peking University,Beijing 100871,china) 2(Department of Physics,shanghai Jiao Tong University,shanghai 200240,people's republic of china)

A spin-conserved potential-energy-surface（PEs） calculation,which takes angular momentum restoration and multi-quasiparticle excitations into account,is developed by using the concepts of the macroscopic-microscopic shell correction and the projected shell model（PsM）.With this method,it may become possible to modify the excitation spectra which are influenced by shape-softness of *** our first example, this method is performed to study the multi-quasiparticle and collective excitations of Hf,which are in good agreement with the existing experimental *** addition,the conflict of the dominant structure of 6 band between experimental results and previous PsM calculations is clarified.

关键词： Nuclear structure Potential-energy surface Projected shell model

The Characterization of Biomass-Carbon and its NOx Removal Mechanism

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The Characterization of Biomass-Carbon and its NOx Removal M...

The 12th Asian Pacific Confederation of Chemical Engineering Congress

作者： Dawei Wang~a Guangli Xiu~(**a,c) Zhaofu Liu~a Yan Wu~a Danian Zhang~a Laiming Wu~b Fangyuan Xu~b Yulin Xie~b a school of Resource and Environmental Engineering,East china University of science & Technology,shanghai 200237,china, b The Research Laboratory for conservation and Archaeology,shanghai Museum,shanghai 200050,china c Research center of Resources /Energy strategy and Circular Economics,East china University of science & Technology,shanghai 200237,Chian

NOx is an important air pollutant which can not only itself bring about corrosion of cultural relic,particularly the painting and calligraphy and costumes but also strengthen the corrosion in- tensity of other air pollutants including sO,*** purpose of this paper is to show appro- priate conditions of bamboo charcoal for NO removal from conservation micro-environment of

关键词： biomass-based carbon nitrogen oxides interface characteristics

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走治理水土流失建设生态农业的新路子

中国水土保持 1997年第10期 22-24页

作者： people’ s Government of Yan’ an City (shaanxi Province) 延安市人民政府陕西省延安市716000

1 治理开发的成效延安市是黄河中游水土流失最为严重的地区之一.水土流失面积2.88万km^2,占总土地面积的78.4%,年平均土壤侵蚀模数9000t/km^2,严重的水土流失不仅是导致群众生活长期贫困的主要原因,也是制约经济、社会持续发展的重要因... 详细信息

1 治理开发的成效延安市是黄河中游水土流失最为严重的地区之一.水土流失面积2.88万km^2,占总土地面积的78.4%,年平均土壤侵蚀模数9000t/km^2,严重的水土流失不仅是导致群众生活长期贫困的主要原因,也是制约经济、社会持续发展的重要因素.新中国建立之后,特别是“七五”以来,我们始终坚持把治理水土流失作为发展经济、脱贫致富的长期战略任务来抓,通过不断地实践、总结、认识和探索,全市的水土流失治理进入了讲求科学、注重效益、大现模治理开发的新阶段.到1996年底,全市共兴修基本农田25.16万hm^2,人均0.16hm^2,造林76.9万hm^2,种草37.18万hm^2,森林覆盖率由新中国建立之初的14.4%提高到42.9%;完成水土流失治理措施面积1.67万km^2,占水土流失总面积的58%.“七五”以来的11年间,年平均治理面积超过1000km^2,治理速度是“七五”前的6.3倍.

关键词：水土流失生态农业治理开发

Potential of Combating Desertification in Hunshandak sandland through Nature Reserve

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Potential of Combating Desertification in Hunshandak Sandlan...

“全国第五届青年植物生态学学术研讨会”暨“第二届植物生理生态学学术研讨会”

作者： YU PENG, GAOMING JIANG, MEIZHEN LIU, sHULI NIU, sHUNLI YU Laboratory of Quantitative Vegetation Ecology, Institute of Botany, the Chinese Academy of sciences, Nanxincun 20, Xiangshan, 100093 Beijing, china QIAN ZHANG, XUAN sHI school of Environmental science, Peking University, 100871 Beijing, china Qisen YANG center of Zoological Evolution and systematics, Institute of Zoology, the Chinese Academy of sciences, No. 130 Zhongguancun Road, 100080 Beijing, china

Desertification, rapidly increasing in area, directly threatens over 250 million people and a third of the earth’s land surface. Although it is well known that desertification could be reversed in most cases if the intensity of land use were reduced, there have been no studies of how this might be achieved on a large scale. This investigation conducted in Hunshandak sandland of North china, explored how creation of a nature reserve might aid restoration of a degraded ecosystem. Experimental data indicate that desertification regions, if designated as a nature reserve, composed of three zone types: a core zone, a buffer zone and a transition zone, could help severely degraded ecosystems be restored with conservation of biodiversity. The buffer zones in moderately desertifiied lands could serve as a base for forage production and/or ecotourism industry. The construction of of eco-logically designed towns (eco-towns) in transition zones could accommodate migrants moved from core zones so as to develop stock production, related industry and ecotourism, This could achieve both economic and environmental sustainable development. Up to now, 5778 local inhabitants in the core zones have been moved out the severe degraded areas with the financial assistance of the central government and moved into three eco-towns of Zhenlan Banner in the Hunshadak sandlands With the objective of greatly enhancing the economic status of the relocated persons whilst restoring the degraded sandlands.

关键词： Desertification sustainable development Nature reserve Urbanization Ecotourism, restoration ecology Hunshandak sandland

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中国防沙治沙60年回顾与展望

中国水土保持科学 2018年第2期16卷 144-150页

作者：包岩峰杨柳龙超孔哲彭鹏肖军姜丽娜卢琦中国林业科学研究院荒漠化研究所北京100091 国家林业局亚太森林网络管理中心北京100021

我国相对于世界其他国家开展防治荒漠化工作的时间较早,成果也相对显著。通过对中国防沙治沙60年的治理回顾,明晰中国治沙事业的发展脉络,总结防沙治沙的技术体系和综合治理模式,讲述防沙治沙的"中国故事",分享"中国经验"和"中国智慧",... 详细信息

我国相对于世界其他国家开展防治荒漠化工作的时间较早,成果也相对显著。通过对中国防沙治沙60年的治理回顾,明晰中国治沙事业的发展脉络,总结防沙治沙的技术体系和综合治理模式,讲述防沙治沙的"中国故事",分享"中国经验"和"中国智慧",开出"中国药方"。希望将我国已经取得的防沙治沙成功经验和典范成果推广至其他区域,并供全球其他相似国家和地区借鉴,展望我国防沙治沙方略的全球示范意义。

关键词：荒漠化防沙治沙中国经验技术与模式 “中国药方”

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西部生态环境重建面临的严峻挑战

首都师范大学学报（自然科学版） 2002年第4期23卷 85-92页

作者：彭珂珊中国科学院水利部水土保持研究所陕西杨凌712100

通过对西部地区生态环境问题的探讨 ,根据近 2 0年来西部地区生态环境恢复与重新研究的理论和实际 ,结合西部地区经济基础差、生产技术落后、经济水平低、贫困人口多 ,特别是恶劣的生态环境严重制约着西部经济快速发展的具体情况 ,科学... 详细信息

通过对西部地区生态环境问题的探讨 ,根据近 2 0年来西部地区生态环境恢复与重新研究的理论和实际 ,结合西部地区经济基础差、生产技术落后、经济水平低、贫困人口多 ,特别是恶劣的生态环境严重制约着西部经济快速发展的具体情况 ,科学的分析了西部大开发生态环境建设面临的水土流失、地质灾害、干旱、土地沙化、草场退化、环境污染等问题 ,提出了生态环境治理之对策 .

关键词：生态环境恶性循环持续发展治理方略西部大开发生态恢复生态重建