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Chinese Geographical Science 1995年第4期5卷 355-364页

作者：董光荣董玉祥李森金炯靳鹤龄刘玉璋 Institute of Desert Research the Chinese Academy of Sciences Lanzhou PRC

The middle reaches of the Yarlung Zangbo River and its two tributaries are an important development and construction region in Xizang(Tibet) in recent years, but the fast development of desertification has caused immense damages to its social and economic development, so the study on desertification in this region is significant. The paper studies the causes and development trend of desertification in this region through analysis of natural and human factors as well as their relationship. It can be concluded that desertification in the study area is one process which is accelerated and intensified by human activities on the basis of the slow natural desertification process. It is resulted from the dislocation of irrational and intensive human activities, fragile eec-environment and meagre natural resources, and tends to become more wide and severe.

关键词： desertification eco-environment the Yarlung Zangbo River Xizang

Select indicators and prioritize solutions for desertification and drought in Binh Thuan,Vietnam

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Chinese Journal of Population,Resources and Environment 2016年第2期16卷 123-132页

作者： Le Trinh Hai Anne Gobin Luc Hens Vietnam Academy of Science and Technology Institute of Geography Remote Sensing Department Flemish Institute for Technological Research(VITO)

The link between climate change and desertification is an important global problem for the United Nations Framework Convention on Climate Change(UNFCCC) and the United Nations Convention to Combat desertification(UNCCD).The coastal provinces in Southern Centre Vietnam are strongly influenced by desertification,which is further exacerbated by climate *** Delphi method was used to select sustainability indicators and then a method of an analytical hierarchy process was applied to prioritize sustainable solutions in Binh Thuan experts to elicit the causes and effects of *** to the panel of 23 experts,27 cause(*** and sunshine duration) and 22 effect(*** and agriculture) indicators were of particular importance to desertification and drought in the *** highest priorities for cause are given to emigration,followed by income from industry and water supply for household *** highest priorities for effect in the area are given to socioeconomic criteria,and in particular to the sub-criteria resettlement due to development projects,building hydropower reservoirs,and implementing irrigation *** system of indicators provides useful information for the future *** study provides a means to uncover the most important criteria perceived as major contributors to desertification and as such enables policy-makers to prioritize solutions for Binh Thuan(Vietnam) by 2015 and a vision in 2020.

关键词： Sustainable assessment Delphi process analytical hierarchy process Binh Thuan province desertification

A long-term record(1995-2019)of the dynamics of land desertification in the middle reaches of Yarlung Zangbo River basin derived from Landsat data

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Geography and Sustainability 2021年第1期2卷 12-21页

作者： Qiqi Zhan Wei Zhao Mengjiao Yang Donghong Xiong Institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu 610041China University of Chinese Academy of Sciences Beijing 10049China Kathmandu Center for Research and Education Chinese Academy of Sciences-Tribhuvan UniversityBeijing 100101China

Widespread desertification in the middle part of the Yarlung Zangbo River(YZR)basin is threatening the sustain-able development of this *** capture this process,a method was proposed for large-scale desertification monitoring by using Landsat images from 1995 to *** method used an integrated classification method combined with a hierarchical decision tree and nearest neighbor *** spatio-temporal dynamics of the desertification pattern were analyzed to assist in the detection of possible driving *** validation samples collected from Google Earth high-resolution images and field investigations,the overall accuracy of the classification in 2019 was 92.3%with a Kappa coefficient of *** major results were:(1)total sandy land area in 2019 was 734.1 km^(2),which accounted for 3.7%of the study area,prominently distributed along the wide river valleys and inlets of tributaries with a strip and discontinuous *** land tends to be distributed in the southern aspect regions with lower elevations and that are closer to rivers;(2)sandy land areas showed two temporal stages:a gradual increase of 102.4 km^(2)from 1995 to 2015 and a large decrease of 106.8 km^(2)from 2015 to 2019;(3)newly increased sandy land was distributed in the YZR Valley,while the revegetation on sandy land occurred mainly in the Lhasa River basin and some regions in the YZR Valley;and(4)increased sandy land area of 142.1 km^(2)was mainly distributed in the southern band of the two ***,revegetation on sandy land was more effective on the northern banks of the river *** findings provide guidance for implementing vegetation recovery on sandy lands and provide important insights for maintaining sustainable development.

关键词： desertification Landsat Spatial-temporal dynamics Yarlung Zangbo River Basin Qingzang Plateau

Application of Remote Sensing and GIS Technology to the Study of desertification of Arable Lands in North Shaanxi, China

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Geo-Spatial Information Science 2004年第3期7卷 187-192页

作者： MushtakTalibJabbar HUGuangdao ZHANGZhenfei ChinaUniversityofGeosciences.31LumoRoad Wuhan430074China. 不详

The policy of the Chinese government concerning the horizontal expansion of the cultivated land through the reclamation of desert soils result in a total increase of 665.985 km 2 during the period 1987\|1999 in North Shaanxi. This increase is less than the loss in arable land by urbanization. The accelerated rate of change in agricultural areas calls for more rapid surveys of urbanization and loss of arable land. Remote sensing has a number of advantages over ground\|based methods for such surveys. The multi\|scale concept of remote sensing data help us study the problem in four towns. Several maps were produced to analyze the situation of urban coverage in different times. The evaluation of the status, rate and risk of urbanization are based on an accepted average of urban increase as 2% of population growth per year.

关键词： urbanization population pressure arable land desertification remotesensing GIS

Study of Sand Dunes and Their Effect on desertification of Cultivated Lands in Shaanxi Province, China Using Remote Sensing Techniques

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Journal of China University of Geosciences 2002年第3期13卷 234-239页

作者： Mushtak Talib Jabbar Hu Guangdao Chen Jianguo Faculty of Earth Resources, China University of Geosciences, Wuhan 430074 Faculty of Earth Resources China University of Geosciences Wuhan 430074

About half of the arid and semi-arid lands in the world are deserts thatcomprise various types of aeolian sand dunes deposits. In Shaanxi Province, aeolian sand dunes coverconsiderable areas of the Yulin desert and northern Jinbian. Sand dunes are moving in the main winddirection and converting some agricultural area to wasteland. Remote sensing of sand dunes helps inthe understanding of aeolian process and desertification. Remote sensing data combined with fieldstudies are valuable in studying sand dunes, regional aeolian depositional history. In particular,active and inactive sand dunes of the north Shaanxi Province were studied using remote sensing andgeographic information system. In this study, we describe the Landsat thematic mapper (TM) images,covering north Shaanxi Province, which were used to study the distribution, shape, size, trends,density and movement of sand dunes and their effect on desertification of cultivated *** was made depending on soil erodibility factor (Ⅰ) and local climatic factor (C) duringthe period (June to September). The result indicates that soil erosion caused sand drift of 8.957 5,7. 03 ton for Yulin and Jinbian, respectively. The mean sand dunes movement rate were 4.37, 3.11 m,whereas, monthly sand dune advance rate were 1. 092 5, 0. 777 5m, for the two locations,respectively. The study reveals that cultivated lands extended obliquely to the direction of sanddune movement are extremely affected, while other segments that extend parallel to the direction ofthe movement are not affected. Accordingly the north Shaanxi Province was divided into areas ofdifferent classes of potential risk. Moreover, blown sands and sand movement from neighboringhighlands also affect the area of western desert.

关键词： sand dunes desertification remote sensing crust index china

PATTERN, CAUSES AND ESSENCE OF desertification IN SAHEL OF WEST AFRICA

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Journal of Geographical Sciences 1995年第1期5卷 91-98页

作者： Ding Dengshan (Department of Geo and Ocean Sciences, Nanjing University, Nanjing 210008People’s Republic of China)

Sahel of Africa is one of the most seriously desertified regions in the world. It becomes notorious owing to severe drought anddesertification occurred during 1968-1973 in the region. This paperdiscusses the causes and essence of desertification in Sahel. Firstiy, thechanges of social and economic conditions in West Africa and theirinfluence on desertification are analysized. Then the pattem ofdesertification is described, and the causes and essence are ***, the author proposes some measures for prevation and control of desertification in the area.

关键词： desertification Sahel overgrazing excess economic activities

PRESENT STATUS AND CAUSE OF LAND desertification IN THE YARLUNG ZANGBO RIVER BASIN

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Chinese Geographical Science 1999年第3期9卷 36-43页

作者：董玉祥李森董光荣

The Yarlung Zangbo River basin is a spacial zone in the south of Xizang, the types, distribution and causes of desertified lands have special features. The type, area, distribution and damage of desertification land in the Yarlung Zangbo River basin are firstly analysed in detail by using latest investigation information. According to the classification criteria of desertified land types and grades, the desertified land in the Yarlung Zangbo River basin can be divided into three grades and five types: fixed sand (dune) land, semi bare sand and gravel land, semi fixed sand (dune) land, base sand and gravel land, and shifting sand (dune) land. The desertified lands in the basin are mainly distributed in the wide valley floor and tributary junction area. The main factors affecting desertification are fragile eco environment, climate warming and drying and over exploitation of land resources. The man made factors leading to desertification in the Yarlung Zangbo River basin are over cutting and over grazing, dominated by over grazing.

关键词： Yarlung Zangbo River basin land desertification desertification cause man made factor

THE IMPACTS OF GLOBAL CHANGE ON desertification IN CHINA

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Journal of Geographical Sciences 1997年第3期7卷 91-104页

作者： Ci Longjun Commission for Integrated Survey of Natural Resources, CAS, Beijing 100101 People’s Republic of China

Global change and desertification are the serious environmental problems in the world today and exert great impacts on human existence and social development. Therefore, the United Nations has set up quite a number of relevant organizations to encourage millions upon millions of people to combat this harmful problem. At the same time, since the 1992 UN Conference on Environment and Development (UNCED) in Rio de Janeiro, the UN Convention to Combat desertification has been signed and this signment of the Convention will powerfully promote the concrete action programs to combat desertification of each affected country and enlarge the exchange and cooperation among the affected countries. According to recent information of UN Organizations, more than 100 countries and their one-fifth world of population are facing the problem of desertification processes and desertification impacts, and are suffering from expansion of desertification. The total areas of arid, semi-arid and dry sub-humid zones cover approximately about 6.5 billion ha, occupying 41 percent of the total land area of the earth. There are 3.6 billion ha of arable land and grazing land under the impact of desertification in the world. From 1984 to 1991, the annual increase of land desertification is 3.4 percent. The harmful results of desertification on human existence in terms of environment, societies and economy are serious and called for great attention from the UN Systems. It is concluded that desertification is the most serious environmental problem in the world and its resulting impact is socially and economically surprising.

关键词： desertification global change CO 2 concentration greenhouse effect China.

Division of desertification climate types and determination of potential range of desertification in China

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Journal of Geographical Sciences 1998年第2期8卷 86-91页

作者： CI Longjun WU BoChinese Academy of Forestry, Beijing 100091 CHINA 

Distribution of desertification climate types in China was analyzed using Thornthwaite's method on calculating potential evapotranspiration (PE), according to the definition provided by the United Nations Convention, by employing meteorological records from 1864 stations in China. The annual PE and the humidity indices were calculated for every station, based on which a distribution map of HI was constructed. The potential range of desertification in China was obtained for the first time, about 3.32 million km2 and makes up about 34.6 percent of the country. The distribution map of HI was compared with the vegetation map of China and the precipitation map of China respectively. In eastern and northern China, the distribution of climate types is basically acceptable, but for QinghaiTibetan Plateau, where Thornthwaite's method on calculating PE is not quite suitable, the isopleths are deviated to the northern side and the potential range of desertification is smaller than expected.

关键词： desertification the Convention to Combat desertification Thornthwaite's method potential evapotranspiration

desertification evolution prediction for lake area of Minqin oasis based on integration of GIS and cellular automata

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Research in Cold and Arid Regions 2012年第3期4卷 222-228页

作者： DongMei Song GenXu Wang Chen Shen Jian Wang YanGuo Fan XiaoYu Li School of Geosciences China University of PetroleumQingdaoShandong 266580China Institute of Mountain Hazard and Environment Chinese Academy of Sciences&Ministry of Water ConservancyChengduSichuan 610041China College of Science China University of PetroleumQingdaoShandong 266580China Cold and Arid Regions Environmental and Engineering Research Institute CASLanzhouGansu 730000China Institute of Applied Ecology CASShenyangLiaoning 110016China

The Minqin oasis is surrounded on three sides by the Tengger Desert and the Badanjilin Desert, and it prevents these two deserts from converging. However, in recent years it has become the worst ecological environment in the Lake area due to deficient water resources, continual declines in the groundwater level and quality （increasing mineralization and salination）, which are causing in- creasing desertification. In this study, Landsat Thematic Mapper （TM） remote images from 1992, 1998, 2002, and 2006 of the Lake area of the Minqin oasis are interpreted to analyze the desertification evolution. A combination of an ArcObjects module and a cellular automata model is used to build a model simulating the desertification dynamics; the forecasting accuracy of this model is shown to reach up to 90%. The desertification situation in 2012 is forecasted by this model, and the results showed that, from 2006 to 2012, the green land area will be reduced by 999.92 hm2 （l.59 percent of the total oasis area）, the desertification land area will be reduced by 3,000.68 hrn2 （4.78 percent of the total oasis area）, and sand land area will increase by 4,000.6 hm2 （6.37 per- cent of the total oasis area）. The sand land is predicted to become more widespread, and more than 18% sand land will be distrib- uted in the center of green land in the Lake area. In other words, more and more abandoned green land （mined farm land） will be transformed into sand land, and this will intensify the desertification.

关键词： desertification cellular automata model Monte Carlo method ArcObjects Lake area Minqin oasis