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Effects of climate change on relationship between water and salts of waters ecosystems in arid zone, China

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Acta Geochimica 2006年第S1期 163-164页

作者： Junfang HUANG1,2, Ranghui WANG1 1 Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 330011, China 2 Graduate School of the Chinese Academy of Sciences, Beijing 100039,China

Research advances on drought resistance mechanism of plant species in arid zones of China

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Research in Cold and arid Regions 2011年第5期3卷 448-454页

作者： YaJuan Zhu Lei Li ZhiQing Jia Institute of Desertification Studies Chinese Academy of Forestry Beijing 100091 China

Drought and shortage of water resources, which restrict the economy, society development and environmental protection, are key factors in arid zones of China. In the arid zones of Western China, researching plant drought resistance mechanism, selecting plant species with higher drought resistance, and developing water-saving techniques, are important for environmental improvement and economic development. This paper reviews research advances on drought resistance mechanism of plant species, based on research of morphological, physiological, and ecological adaptation mechanism of plant species under drought stress, such as anatomical structure of root systems and leaves, photosynthesis, antioxidant enzyme system, malondialdehyde （MDA）, osmotic adjustment, endogenous hormone, drought-induced proteins and δ^13C. Finally, this paper points out the key field of future research.

关键词： arid zone drought resistance drought resistance mechanism evaluated index

A method to estimate aquifer artificial recharge from a hill dam in Tunisia

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Journal of arid Land 2017年第2期9卷 244-255页

作者： Zouheira IBN ALI Ibtissem TRIKI Lamia LAJILI-GHEZAL Moncef ZAIRI Water Energy and Environment Laboratory (LR3E) National School of Engineering of Sfax (ENIS) University of Sfax Sfax 3038 Tunisia Higher School of Agriculture Mograne Mograne 1121 Tunisia

in arid and semi-arid areas, artificial recharge is a key technology in groundwater resources management, and a reliable estimate of artificial recharge is necessary to its sustainable development. Several methods are available to estimate the artificial recharge; however, most of them require field data or model parameters, thus limiting their applications. To overcome this limitation, we presented an analytical method to estimate the artificial recharge through monitoring the water release by piezometer and analysing the controlling factors of the artificial recharge from a hill dam in Tunisia. A total of 97 measurements of water flow in the streambed recorded from 4 gauging stations were analysed. Results indicated that the average infiltration velocity ranged from 0.043 to 0.127 m/d and the infiltration index varied from 7.6 to 11.8 L/（***）. Pearson＇s correlation coefficient analysis shows that the infiltration index, the stream gradient, the thickness of unsaturated zone, the number of infiltration pond, the stream geometry, and the water flow rate were found to be the main factors in determining the infiltration. The high correlation coefficients （0.908 for the number of infiltration pond and 0.999 for the stream geometry） mean that the number of infiltration pond and the stream geometry are the most influential factors. Time variations of groundwater level were used to analyze the recharge effects on the piezometry of aquifer. The analysis showed that during the artificial recharge, the water table increased at a rate of 5 mm/d and that the increase was limited to the area surrounding the recharge site. Based on the results of the study, building infiltration ponds along streambed and improving the potential of rainwater harvesting over the study area are recommended.

关键词： arid zone water shortage dam water release infiltration index piezometry

Some Phenomena of the Interaction Between Vegetation and a Atmosphere on Multiple Scales

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Advances in Atmospheric Sciences 2006年第4期23卷 639-648页

作者：胡隐樵陈晋北郑元润李国庆左洪超 Key Laboratory of arid Climatic Change and Reducing Disaste of Gansu Province Cold and arid Regions Environment and Engineering Institute CAS College of Atmospheric Sciences Lanzhou University Institute of Botany CAS

This article studies the response of the distribution pattern and the physiological characteristics of the ecosystem to the spontaneous precipitation and the interaction between vegetation and the atmosphere on multiple scales in arid and semi-arid zones, based on measured data of the ecological physiological parameters in the Ordas Plateau of northern China. The results show that the vegetation biomass and the energy use efficiency of photosynthesis are especially sensitive to the annual precipitation; strong and complex interactions exist between the vegetation and the atmosphere on multiple scales leading to supernormal thermal heterogeneity of the underlying surface, the strong vortex movement and turbulence. This study can facilitate understanding of the land surface processes and the influences of global climate change as well as human activities on the human environment in the arid and semi-arid zones. It also aids in improving the parameterization schemes of turbulent fluxes of a heterogeneous underlying surface for land surface processes in climate models.

关键词： climate arid zone precipitation ecosystem climate change

Metals content in sediments of ephemeral streams with small reservoirs(the Negev Desert)

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International Journal of Sediment Research 2020年第3期35卷 269-277页

作者： Ma?gorzata Kijowska-Struga?a ?ukasz Wiejaczka Rafa? Koz?owski Judith Lekach Polish Academy of Sciences Institute of Geography and Spatial OrganizationResearch Station in Szymbark Polish Academy of Sciences Institute of Geography and Spatial OrganizationDepartment Polish Academy of SciencesInstitute of Geography and Spatial OrganizationDepartment of Geoenvironmental Research The Jan Kochanowski University Institute of Geography and Environmental Sciences Bar-Ilan University Department of Geography and Environment

The content of 19 metals(chromium,cobalt,nickel,strontium,arsenic,magnesium,barium,cesium,gallium,rubidium,uranium,vanadium,zinc,lead,copper,cadmium,iron,manganese,and aluminum) in sediment in three ephemeral streams(Nahal Sansana,Nahal Revivim and Nahal Pura) with reservoirs in the Negev Desert is studied *** study was done in September *** samples were collected from the surface layer of sediment(up to 10 cm) in the reservoirs and in the channels upstream and downstream of the ***,which on average,accounted for 72% dominated in the *** the spatial distribution of the particle size,sand and gravel fractions were deposited in the ***,iron,and magnesium accounted for 99% of all analyzed *** Principal Component Analysis(PCA) and Hierarchical Cluster Analysis(HCA) showed that sediment in the Negev Desert channel upstream of the reservoirs had similar concentrations of *** were also found between the analyzed *** bottom sediment in reservoirs had higher concentrations of metals than sediment upstream and downstream of the *** comparison of concentrations in upstream and downstream locations did not show any unambiguous trends because metal concentrations downstream from the reservoirs were not always lower than upstream of the *** analysis of the sediment enrichment factor(EF) showed the highest value in the reservoirs and the lowest downstream of the *** concentrations of most analyzed metals did not indicate the possibility of potential ecological risk(SQG).

关键词： Metal content Sediment Reservoir arid zone Israel

Water conservation in the Arab region: a must for survival

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Research in Cold and arid Regions 2013年第1期5卷 157-164页

作者： Gamal M. Abdo Abdin M. A. Salih Abdulmohsen Al-Sheikh Civil Engineering Department University of Khartoum Sudan Alzamil Group Chair King Saud University Riyadh Saudi Arabia

The Arab region covers an area over 13 million square kilometers in size, with almost 90% of its area classified as arid or ex- tremely arid with very little precipitation, extremely high evaporation and almost no vegetation cover. The region is classified in many international reports as the poorest region in the world in the context of renewable water resources and critical water scarcity which hinders the socio-economfic development of many countries in this region. The rapidly increasing population has reduced the per capita share of renewable water to less than the poverty line of 1,000 m3/（capita＇a） and, in some Arab countries, to less than the extreme poverty line of 500 m3/（capita＇a）. This has led to over-exploitation of non-renewable groundwater and desalination of salty water in many countries with considerable costs and contamination of many renewable sources. Atmospheric processes re- sponsible for aridity in the Arab region are projected to intensify due to climate change, resulting in an alarming decrease in pre- cipitation and increase in evaporation rates. Many concerned entities in the region consider water security as a key element for food security and ultimately political stability. Hence, various efforts have been exerted to identify key problems and suggested solutions. The Arab Water Ministers Council of the Arab League, as well as Reports of the Arab Forum for the Environment and Development （AFED） and the recommendations of the 13th Regional Meeting of the Arab National Committees of the Interna- tional Hydrological Programme of UNESCO （niP）, have all made similar recommendations on the need to address the issues of water scarcity in the Arab region which will be further discussed in this paper. However, none of these reports focused on ＂Water Conservation＂ as an equally important action for coping with water scarcity in the region. There are many definitions for ＂Water Conservation＂ in the scientific literature, including huge water savings

关键词： arid zone water scarcity water security irrigation efficiency climate change water harvesting water reuse

Climate Change and Desertification with Special Reference to the Cases in China

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Climate Change and Desertification with Special Reference to...

The New Progresses in Coupling Relations of Mountain-oasis-desert System

中国科学院地质与地球物理研究所第十届(2010年度)学术年会

作者： Xiaoping Yang Institute of Geology and Geophysics,Chinese Academy of Sciences,Beijing 100029,China

This chapter briefly reviews the terminological origin,development and the latest status of desertification and demonstrates the significant impact of the climatic variations in the processes of desertification and its *** typical arid regions at Asia’s middle latitudes are selected as cases for studies, i.e.,the oases in the hyper-arid Taklamakan Desert in the west and the semi-arid Hunshandake Sandy Land in the east(Fig.1).It shows that humans set up cultivation bases in the center of the Taklamakan Desert over 2,000 years ago and the later abandonment of these bases was probably caused by decrease in runoffs associated with *** shaping the landscape changes between soil formation and aeolian sedimentation in the Hunshandake,the role played by the Holocene changes of East Asia summer monsoons surpasses the impact of human activities since the Neolithic time,meaning that the climatic background and its potential changes should be given greater attention in the aims and schemes of combating desertification. The rapid vegetation regeneration in recent years in the Hunshandake reconfirms the great importance of climatic background in ecological rehabilitations in desertified *** the course of global warming,the risks of desertification are likely to increase in both areas due to different reasons.

关键词： Desertification Climatic change Oasis arid zone Semiarid area China

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Science Foundation in China 2006年第1期14卷 54-59页

作者： Ranghui Wang Huizhi Zhang Qing Huang Xinjiang Institute of Ecology and Geogrphy CAS Urumqi 83001

In this paper, the concepts and principles of mountain-oasis-desert system （MODS） are put forward according to the natural geographical situations in arid zone of western china, The spatiotemporal characteristics and dynamic changes of typical MODS, the process of material circulation, energy transform and information transmission among MODS and the mechanism of MODS interaction and symbiosis are analyzed. The foundation and frame of the coupling type are determined by landform types and climate characteristics： the spatial pattern of the coupling type is determined by the hydrological characteristics; the vegetation type reflects the appearance of the coupling type; the soil state restdcta the function of the coupling type and the human activities influence the development course of the coupling type. Interface course of MODS is closely related to such medium as water, soil, air, etc., and water is the major medium during the course of material circulation, energy transform and information transmission. The disorder of water salt, water heat and water land restricts the stability of water ecosystem.

关键词： mountain-oasis-desert system (MODS) arid zone hydrological process interface and coupling relation

The origin and distribution of soluble salts in the sand seas of northern China

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The origin and distribution of soluble salts in the sand sea...