نتایج جستجو برای: china desert

تعداد نتایج: 212740  

2015
Jiu Jimmy Jiao Xiaotao Zhang Xusheng Wang

Despite prevailing dry conditions, groundwater-fed lakes are found among the earth's tallest sand dunes in the Badain Jaran Desert, China. Indirect evidence suggests that some lakes are shrinking. However, relatively few studies have been carried out to assess the regional groundwater conditions and the fate of the lakes due to the remoteness and severity of the desert environment. Here we use ...

2018
Xing Wang Xinguo Yang Lei Wang Lin Chen Naiping Song Junlong Gu Yi Xue

Excluding grazers is one of most efficient ways to restore degraded grasslands in desert-steppe communities, but may negatively affect the recovery of plant species diversity. However, diversity differences between grazed and fenced grasslands in desert-steppe are poorly known. In a Stipa breviflora desert steppe community in Northern China, we established six plots to examine spatial patterns ...

2014
Mingzhu He Feike A. Dijkstra Ke Zhang Xinrong Li Huijuan Tan Yanhong Gao Gang Li

In desert ecosystems, plant growth and nutrient uptake are restricted by availability of soil nitrogen (N) and phosphorus (P). The effects of both climate and soil nutrient conditions on N and P concentrations among desert plant life forms (annual, perennial and shrub) remain unclear. We assessed leaf N and P levels of 54 desert plants and measured the corresponding soil N and P in shallow (0-1...

2006
B. Laurent G. Bergametti F. Mei

The present study investigates the frequency and intensity of mineral dust emissions over the deserts of eastern Asia from 1996 to 2001. Mineral dust emissions are simulated using a physical dust emission scheme over a region extending from 35.5°N to 47°N and from 73°E to 125°E. The input parameters required by the dust emission model are (1) surface features data including aerodynamic roughnes...

2015
Lei Huang Zhishan Zhang Lutz Breuer

The stability and sustainability of revegetated ecosystems is a central topic in ecological research. In this study, long-term monitoring and focused research on vegetation, soil and soil moisture from 2006 to 2012 were used to develop a model for evaluating indices of ecosystem stability using the analytical hierarchy process method. The results demonstrated that rainfall (R), vegetation cover...

2018
Xiaolong Zhang Tianyu Guan Jihua Zhou Wentao Cai Nannan Gao Hui Du Lianhe Jiang Liming Lai Yuanrun Zheng

Precipitation is a key environmental factor determining plant community structure and function. Knowledge of how community characteristics and leaf stoichiometric traits respond to variation in precipitation is crucial for assessing the effects of global changes on terrestrial ecosystems. In this study, we measured community characteristics, leaf stoichiometric traits, and soil properties along...

2018
Weiwei She Yuxuan Bai Yuqing Zhang Shugao Qin Wei Feng Yanfei Sun Jing Zheng Bin Wu

Desert microbes are expected to be substantially sensitive to global environmental changes, such as precipitation changes and elevated nitrogen deposition. However, the effects of precipitation changes and nitrogen enrichment on their diversity and community composition remain poorly understood. We conducted a field experiment over 2 years with multi-level precipitation and nitrogen addition in...

Journal: :محیط شناسی 0
امیر هوشنگ احسانی دانشیار گروه مهندسی طراحی محیط زیست، دانشکدۀ محیط زیست، دانشگاه تهران مرضیه فروتن دانشجوی دکتری، جغرافیا، دانشگاه کالگری کانادا

introduction morphological segmentation of land surface is commonly used for land surface allocation in management and environmental sciences. the first step in assigning a piece of land to a specific application is to divide it into homogeneous morphological segments. traditional field-based geomorphological mapping can be time consuming, costly, and challenging when large areas, particularly ...

2014
Offer Rozenstein Zhihao Qin Yevgeny Derimian Arnon Karnieli

1 The Remote Sensing Laboratory, Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede Boker Campus, Midreshet Ben-Gurion 84990, Israel; E-Mail: [email protected] 2 Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China; E-Mail: [email protected] 3 Laboratoire d’Optique Atmosphérique, Universi...

Journal: :International Journal of Geographical Information Science 2016
Weibo Liu Xingong Li David A. Rahn

Storm event representation and analysis based on a directed spatiotemporal graph model Weibo Liu, Xingong Li & David A. Rahn a Department of Geography, University of Kansas, Lawrence, KS, USA b State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi, China c Atmospheric Science Program, Department of Geography, Universit...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید