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desertification dynamic and the relative roles of climate change and human activities in desertification in the Heihe River Basin based on NPP

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Journal of Arid Land 2013年第4期5卷 465-479页

作者： Wei ZHOU ZhengGuo SUN JianLong LI ChengCheng GANG ChaoBin ZHANG School of Life Science Nanjing University

Relative roles of climate change and human activities in desertification are the hotspot of research on desertification dynamic and its driving *** overcome the shortcomings of existing studies,this paper selected net primary productivity （NPP） as an indicator to analyze desertification dynamic and its impact *** addition,the change trends of actual NPP,potential NPP and HNPP （human appropriation of NPP,the difference between potential NPP and actual NPP） were used to analyze the desertification dynamic and calculate the relative roles of climate change,human activities and a combination of the two factors in *** this study,the Moderate Resolution Imaging Spectroradiometer （MODIS）-Normalised Difference Vegetation Index （NDVI） and meteorological data were utilized to drive the Carnegie-Ames-Stanford Approach （CASA） model to calculate the actual NPP from 2001 to 2010 in the Heihe River *** NPP was estimated using the Thornthwaite Memorial *** showed that 61％ of the whole basin area underwent land degradation,of which 90.5％ was caused by human activities,8.6％ by climate change,and 0.9％ by a combination of the two *** the contrary,1.5％ of desertification reversion area was caused by human activities and 90.7％ by climate change,the rest 7.8％ by a combination of the two ***,it was demonstrated that 95.9％ of the total actual NPP decrease was induced by human activities,while 69.3％ of the total actual NPP increase was caused by climate *** results revealed that climate change dominated desertification reversion,while human activities dominated desertification ***,the relative roles of both climate change and human activities in desertification possessed great spatial ***,ecological protection policies should be enhanced in the Heihe River Basin to prevent desertification expansion under the condition of climate change.

关键词： desertification net primary productivity (NPP) climate change human activities quantitative assessment Heihe River Basin

desertification IN THE NORTHERN TERRITORY OF CHINA:PRESENT STATUS AND TREND OF DEVELOPMENT

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Journal of Geographical Sciences 1990年第1期1卷 61-70页

作者： Zhu Zhenda Institute of Desert Research CAS

The preset situation of desertification and trend of its future development are dealt with *** impact on the fragile ecosystem in arid and semi-arid zones is quite *** way to improve the situation lies in proper utili... 详细信息

关键词： desertification rehabilitation measure

Diverse responses of fungal functional groups to desertification in forest soils of Pinus densata on the Chinese Tibetan plateau

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Journal of Forestry Research 2024年第5期35卷 120-130页

作者： Jiani Hua Jiangbao Zhang Baohan Song Tianyi Wang Jingji Li Nan Yang Lingfeng Mao Co-Innovation Center for Sustainable Forestry in Southern China Laboratory of Biodiversity and ConservationCollege of Ecology and EnvironmentNanjing Forestry University210037 NanjingPeople’s Republic of China Institute of Ecological Resources and Landscape Architecture Chengdu University of Technology610059 ChengduPeople’s Republic of China

Rapid increase in desertification is an environ-mental concern,especially for the health and sustainabil-ity of ecosystems in changing *** ecosystems respond to such changes may be partially understood by studying interactions and performance of critically impor-tant groups such as soil fungi functional *** study investigated variations in diversities of three soil fungi functional guilds(saprotrophic,symbiotic,pathogenic)and influencing abiotic factors in a Pinus densata forest on the southeast Tibetan Plateau where desertification is *** results indicate desertification significantly decreased the proportion of dominant fungal guild-symbiotic fungi(mean relative abundance decreasing from 97.0%to 68.3%),in contrast to saprotrophic fungi(increasing from 2.7%to 25.7%)and pathogenic(from 0.3%to 5.9%).Soil pH had the most significant impact on fungal community structure and negatively correlated with symbiotic fungal richness,which was significantly lower in arid soils,and positively correlated with saprotrophic and pathogenic fungal alpha-diversity,which were *** community struc-tures and regulators of the three fungi communities were observed,with pH,total phosphorus and ammonium(NH_(4)^(+))as the main *** study links the biotic and abi-otic components during desertification and the interactions between them,and may be used as indicators of ecosystem health and for amendments to mitigate the effects of a chang-ing climate.

关键词： desertification Fungal diversity Saprotrophs Ectomycorrhizal fungi Climate change

Monitoring interannual dynamics of desertification in Minqin County,China,using dense Landsat time series

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International Journal of Digital Earth 2020年第8期13卷 886-898页

作者： Xiaolin Zhu Kwok Huen Leung Wing Sze Li Lek Kin Cheung The Department of Land Surveying and Geo-Informatics The Hong Kong Polytechnic UniversityHong KongPeople’s Republic of China The Hong Kong Polytechnic University Shenzhen Research Institute ShenzhenPeople’s Republic of China

Minqin County in northwestern China is highly affected by *** have been initiated in recent decades to combat desertification in *** assess the effectiveness of these campaigns,this study used a dense Landsat time series from 1987 to 2017 to investigate the interannual dynamics of vegetation coverage and greenness over the past 31 ***,this study applied an advanced technology to reconstruct a high-quality Landsat annual time ***,one image in the vegetation-peak season was selected as the base image in each year,and then problematic pixels were interpolated by the neighborhood similar pixel interpolator using ancillary images in the same ***,the land cover map and the enhanced vegetation index(EVI)were derived from all reconstructed ***,the change of vegetation coverage and EVI values over the 31 years were *** results show that the total vegetation coverage and greenness increased during the 31 *** this change trend to other factors suggests that vegetation in Minqin County is highly affected by agriculture and groundwater supply rather than by *** mitigate desertification in a sustainable way,agriculture should be well managed to avoid overconsumption of natural resources such as underground water.

关键词： Minqin County desertification agriculture Landsat time series vegetation cover

desertification: China provides a solution to a global challenge

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Frontiers of Agricultural Science and Engineering 2017年第4期4卷 402-413页

作者： Yingshuang BAO Leilei CHENG Yanfeng BAO Liu YANG Lina JIANG Chao LONG Zhe KONG Peng PENG Jun XIAO Qi LU Institute of desertification Studies Chinese Academy of Forestry Research Institute of Forestry New Technology Chinese Academy of Forestry Asia-Pacific Network for Sustainable Forest Management and Rehabilitation

desertification has been caused by various factors and is a major environmental problem and development bottleneck faced by the world. It is also a serious threat to ecological security and to sustainable economic and social development. As a stubborn world problem, focused on by the United Nations 2030 sustainable development goal 15.3, China aims to combat desertification by implementing the "eight-column fourbeam" strategy, and also suggest the "four-medicine"approach for global desertification governance. This includes the development of the United Nations Convention to Combat desertification protocol, unified global compliance and compliance metrics; building a global observation network, and monitoring land changes based on remote sense; preparing the global natural desert(heritage) list, leaving the original deserts for future generations; initiating the global action of combating desertification, and striving to achieve a land degradationneutral world by 2030.

关键词： desertification global governance land degradation neutrality LDN origin status strategy sustainable development

Evolution of desertification in a two-dimensional energy balance model coupled with thermodynamics and dynamics

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Science China Earth Sciences 2010年第11期53卷 1726-1733页

作者： CHAO JiPing1,2 & LI YaoKun3,4 1National Marine Environmental Forecasting Center, Beijing 100081, China 2First Institute of Oceanography, State Oceanic Administration, Qingdao 266061, China 3State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China 4Graduate University of Chinese Academy of Sciences, Beijing 100049, China 1. National Marine Environmental Forecasting Center Beijing 100081 China2. First Institute of Oceanography State Oceanic Administration Qingdao 266061 China3. State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China4. Graduate University of Chinese Academy of Sciences Beijing 100049 China

The relationship between desert evolution and change in albedo has been investigated quasi-analytically using a zonal mean two-dimensional energy balance model which considers the radiation transmission process due to thermodynamics and bound- ary layer movement caused by kinetics. A climate state including temperature, zonal wind, meridional wind and vertical wind can be simulated according to the current zonal distribution of albedo. Given desert distribution, characterized by the value and distribution of albedo, the response of climate on albedo has been studied to analyze the evolution of desert climate. One significant result is that the simple model can reproduce mean meridional circulation. Another result indicates that climate corresponds to two equilibria. This happens when the junction temperature between vegetation and desert is higher than a certain critical value. As for the first equilibrium, the desert belt is predicted to move southward in the northern hemisphere with the increasing values of albedo, which corresponds to the current trend of climate change. For the second equilibrium, vegetation will expand northward with increasing values of albedo, which would indicate a narrowing of the desert belt. In order to determine if the two equilibria exist, new physical models are needed.

关键词： two-dimensional energy balance model desertification two equilibria

Diverse Climatic and Anthropogenic Impacts on desertification in the Middle Reaches of Yarlung Zangbo River Catchment on the Tibetan Plateau

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Journal of Earth Science 2023年第6期34卷 1816-1826页

作者： Qi Yu Xianyan Wang Zhiyong Han Xiaodong Miao Huayu Lu School of Geography and Ocean Science Nanjing UniversityNanjing 210023China Key Laboratory of Tibetan Plateau Land Surface Processes and Ecological Conservation(Ministry of Education) Xining810016China Shandong Provincial Key Laboratory of Water and Soil Conservation and Environmental Protection School of Resource and Environmental SciencesLinyi UniversityLinyi 276000China

The unique desertification processes occurring under the Alpine climate and ecosystem on the Tibetan Plateau could provide critical clues to the natural and anthropogenic impacts on *** study used the Landsat data to investigate the spatial and temporal distribution of desertification from 1990 to 2020 in two areas(Shannan and Mainling),within the Yarlung Zangbo River *** results show not only distinct spatial patterns but also various temporal changes of *** Shannan,aeolian sand was distributed over wide areas from valley floor to mountain slope,while in Mainling,it is distributed sporadically at the *** aeolian sandy land initially expanded before undergoing long-term shrinkage in *** in Mainling,it steadily expanded followed by a rapid *** changes are attributed to both climate change and human *** increase in temperature causes desertification expansion in Shannan,while favorable climate conditions coupled with decreasing human activity promoted desertification ***,both the expansion and shrinkage of desertification were sensitive to human activity in *** highlights the diverse responses of desertification to natural and anthropogenic impacts on different backgrounds of climatic and vegetation coverage.A threshold of climatic conditions may control the dominance factors in desertification,shifting from natural to anthropogenic elements.

关键词： desertification reversal of desertification human activities climate change remote sensing Yarlung Zangbo River valley

Mapping desertification potential using life cycle assessment method: a case study in Lorestan Province, Iran

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Journal of Arid Land 2019年第5期11卷 652-663页

作者： Abolfazl RANJBAR Somayeh HEYDARNEJAD Sayed H MOUSAVI Roohallah MIRZAEI Department of Desert Studies University of KashanKashan ***Iran Department of Geography and Ecotourism University of KashanKashan ***Iran Department of Environmental Sciences University of KashanKashan ***Iran

In recent year,desertification has become one of the most important environmental hazards all over the world,especially in developing countries such as *** the factors impacting on desertification and identifying the regions with high desertification potential are essential to control this phenomenon(i.e.,desertification).The life cycle assessment(LCA)method is essential in assessing the desertification of ecosystems,especially for susceptible ecosystems with high degradation *** aim of the present study was to evaluate the desertification potential of Lorestan Province,Iran,based on the LCA *** selected aridity,fire and dust as three indicators of desertification and collected data from 2000 to *** divided the study area into 6 types of ecoregions according to the climate types(arid,semi-arid and dry sub-humid)and dominant species(Quercus brantii and Astragalus adscendens),and calculated the characteristic factor(CF)of each indicator(aridity,fire and dust)by combining the indicator layers and ecoregion layer of the study *** a given ecoregion,the sum of CF values of aridity,dust and fire indicators represents the life cycle inventory(LCI)desertification value(the higher the LCI value,the greater the desertification potential).Then,we obtained the desertification potential map by combining and overlapping the ecoregions and the normalized indicators based on the LCA *** and fire exhibit significant impacts on desertification in the study area compared with *** the study area,semi-arid ecoregion with Quercus brantii as the dominant species is the largest ecoregion,while arid ecoregion with Quercus brantii as the dominant species is the smallest *** ecoregion with Astragalus adscendens as the dominant species(LCI desertification value of 1.99)and dry sub-humid ecoregion with Quercus brantii as the dominant species(LCI desertification value of 0.79)show the highest and lowest desertification potentials,respec

关键词： life cycle assessment characterization factor desertification potential aridity index fire risk dusty days Lorestan Province

Soil quality assessment for desertification based on multi-indicators with the best-worst method in a semi-arid ecosystem

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Journal of Arid Land 2023年第7期15卷 779-796页

作者： Orhan DENGİZ İnci DEMİRAĞTURAN Department of Soil Science and Plant Nutrition Faculty of AgricultureOndokuz Mayıs UniversitySamsun-55139Turkey Department of Geography Faculty of EconomicAdministrative and Social SciencesSamsun UniversitySamsun-55030Turkey

Since there are some signs of land degradation and desertification showing how soil sustainability is threatened, it is crucial to create a soil quality index(SQI) model in the semi-arid ?orum Basin, situated between the Black Sea and Anatolia Region, Central Turkey. The primary aims of the study are:(1) to determine SQI values of the micro-basin in terms of land degradation and ***, the best-worst method(BWM) was used to determine the weighting score for each parameter;(2) to produce the soils' spatial distribution by utilizing different geostatistical models and GIS(geographic information system) techniques;and(3) to validate the obtained SQI values with biomass reflectance values. Therefore, the relationship of RE-OSAVI(red-edge optimized soil-adjusted vegetation index) and NDVI(normalized difference vegetation index) generated from Sentinel-2A satellite images at different time series with soil quality was examined. Results showed that SQI values were high in the areas that had almost a flat and slight slope. Moreover, the areas with high clay content and thick soil depth did not have salinity problems, and were generally distributed in the middle parts of the basin. However, the areas with a high slope, poor vegetation, high sand content, and low water holding capacity had low SQI ***, a statistically high positive correlation of RE-OSAVI and NDVI indices with soil quality was found, and NDVI had the highest correlative value for June(R~2=0.802) compared with RE-OSAVI.

关键词： soil quality land degradation desertification best-worst method remote sensing