Hydrology and water resources variation and its response to regional climate change in Xinjiang

Based on the surface runoff, temperature and precipitation data over the last 50 years from eight representative rivers in Xinjiang, using Mann-Kendall trend and jump detection method, the paper investigated the long-term trend and jump point of time series, the surface runoff, mean annual temperature and annual precipitation. Meanwhile, the paper analyzed the relationship between runoff and temperature and precipitation, and the flood frequency and peak flow. Results showed that climate of all parts of Xinjiang conformably has experienced an increase in temperature and precipitation since the mid-1980s. Northern Xinjiang was the area that changed most significantly followed by southern and eastern Xinjiang. Affected by temperature and precipitation variation, river runoff had changed both inter-annually and intra-annually. The surface runoff of most rivers has increased significantly since the early 1990s, and some of them have even witnessed the earlier spring floods, later summer floods and increasing flood peaks. The variation characteristics were closely related with the replenishment types of rivers. Flood frequency and peak flow increased all over Xinjiang. Climate warming has had an effect on the regional hydrological cycle.

Variation Trends of Hydrology and Water Resources in Yangtze River Delta Region,China and Its Responses to Climate Change

Global warming has become one of important environmental issues, and will alter the spatial distribution of hydrology and water re- sources through accelerating atmospheric and hydrological cycles. Yangtze River Delta region, an economic center in China, has experienced a re- gional temperature increase since the 1960s, forming a heat island, and the warming rate has improved since the 1990s. The characteristics of hy- drology and water resources changed under regional climate warming. Here, the impacts of climate change on hydrology and water resources were discussed from the aspects of precipitation change, sea level rise, seawater invasion and water pollution in Yangtze River Delta region, China.

Soil and Water Resources and Land Sustainable Productivity in the Catchment Area with Intensive Management in Hilly Red Soil Regions,China

Taking an example of Majiayu Catchment Area (14.15 ha) in Taoyuan County of HunanProvince, the soil and water resources dynamics, fertility evolution characteristics andland productivity changing situation were studied. Fixed observation results from 1993to 2002 showed that pools covering about 15% of total area could store up 10% of surfacerunoff, keep 78.1% of eroded soil and 65.4% of lost nutrients. The yearly ratio ofinterception and evapotranspiration in land, storage in pools and drainage was 7:2:1,which ensured the resources and nutrients equilibrium and a benign recycle in thecatchment area system, and benefited the aquatic culture and helped to resist seasonaldrought. Moreover, the results showed that soil erosion modulus decreased significantly,equal to or lower than soil loss tolerance (≤500 tkm-2) in reddish yellow soil regions.Soil organic matter, total and available N content in sloping land, dryland and paddyfield increased steadily (>10%); water storage enhanced by more than 20% in sloping landand dryland in drought season; crop production increased by more than 20%; and productionof trees, fruits, tea and fish as well as land productivity increased yearly.

Spatio-temporal analysis of urbanization and land and water resources efficiency of oasis cities in Tarim River Basin

This paper examines the spatial pattern of land and water resources as well as urbanization and their interactions in the Tarim River Basin, Xinjiang, China. In order to do so, we extract the data associated with efficiency of land and water resources and urbanization for the years of 1995, 2000, 2005 and 2008. Specifically the paper investigates the extent to which agglomeration of population and economic activities varies geographically and inter- plays with spatial pattern of resources efficiency through computation of Global Moran＇s I index, Getis-Ord Gi＊ index and a coordinated development model. The method used provides clear evidence that urbanization, land and water resources efficiency have shown uneven spatial pattern due to oasis distribution, climate, and initial phase of urban development. Some conclusions can be drawn as follows. （1） Agglomeration and dispersion of urbanization are not consistent with those of land and water resources efficiency. （2） Evolution of the hot and cold spots of urbanization, and land and water resources efficiency, in different trajecto- ries, indicate that there are no significant interactions between them. （3） The evidence that numbers of hot and cold spots of the three factors present varying structures reveals the dominance of unequal urban development in the study area. （4） Significant differences are also found between sub-river basins in terms of the three factors, which is a reflection of the complex physical geography of the area. （5） The degree of coordinated development of cities in the Tarim River Basin is generally low in part as a reflection of difference in spatial patterns of the three factors. It is also shown that the pattern of the degree of coordinated development is relatively stable compared with evolution of hot and cold spots of the three factors.

Water resources development in Turkey

The Southeastern Anatolia Projec(tGAP),one of the most important projects for developing remarkable natural resources of the world,is accepted as a change for getting benefit from rich water and agricultural resources of the Southeastern Anatolia Region.The GAP Project has been considered as a regional development projects through years,but the dimensions of sustainability,protection of environment and participatory have been attached to the master of the project in recent years.When the GAP Project is completed,the Upper Mesopotomia, the centers of many civilisation,will re-again its importance as it had in the ancient times,and will be alive a center of civilisation.Moreover,when the problem of water shortage and water supplies in the world for the future is kept in mind,the importance of Southeastern Anatolia′s water supplies will be doubled.For this reason,the GAP Project,developed by depending on water and natural resources of the region,will have an important place in the world.The aim of this study is to introduce the region with rich natural resources and the GAP Project.For this reason,firstly,the natural potential of the region will be introduced.Second,the GAP Project will be presented in details.In the third stage,the projects being processed for protecting the natural sources and environment will be analyzed.In the last stage,strategies and policies to develop and to protect the natural resources of the region in short,mid,and long terms will be proposed.

Concurrent mining and reclamation for underground coal mining subsidence impacts in China

Large scale underground mining of coal resources in China using longwall mining has resulted in ecological and environment problems, including surface subsidence that is considered serious due to competing interests of prime agricultural lands, food security, and regional economic development. The subsided lands must be rehabilitated soon after mining to be agriculturally productive to minimize loss of farmland. Similarly, precious water resources must also be managed during and after mining to protect this natural resource. Toward these goals, the concept of ＂Concurrent mining and subsidence reclamation （CMR）＂ was proposed by Professor Hu of the China University of Mining and Technology, Beijing （CUMTB）. Over the last two decades CMR concepts have evolved and successfully applied in the field in different parts of China. This innovative technology has increased available farmland during the mining process, and provided better land protection and food security in mining areas even with high groundwater table. The technology has been used in 5 of the 14 large coal bases in China. This paper describes the technology concepts, design and guiding principles for planning with two case studies from different regions to enhance its application both in China and in other countries.

Geomorphology and Hydrology of the Benin Region, Edo State, Nigeria

This paper examines the geomorphology and hydrology of the Benin Region, Edo State, Nigeria. The major landform features and processes of the region are highlighted. This region is a strategic and significant landscape in Nigeria. Information was gathered on the various aspects of the landscape, including the Geology, Physiography (Relief) and Geomorphology, Geomorphic processes, Weathering, Drainage processes, Landforms, Surface Water Hydrology and Water Resources. The Benin Region is underlained by sedimentary formation of the South Sedimentary Basin. The geology is generally marked by top reddish earth, composed of ferruginized or literalized clay sand. Geologically, the Benin Region comprises of 1) the Benin formation;2) alluvium;3) drift/top soil and 4) Azagba-Ogwashi (Asuba-Ogwashi) formation. Several parts of the region are surrounded by the Benin historical moats. The region has been described as a tilled plain in the south western direction. The local relief of the region is 91 m. Boreholes records in the Benin Region show evidence of deep chemical weathering overtime. Soil profile reveals that the region is composed mainly of reddish brown sandy laterite. Intermittent layers of porous sands of sandy clays may reach a large depth as found in the borehole drilled in the region. These are products of deep chemical decay of the original parent rock materials. Three river systems drain the Benin Region. They are the Ikpoba River, the Ogba River and Owigie-Ogbovben River systems. The mean annual discharge of Ikpoba River for 1982-1983 and 1993-2002 was 1411 mm/yr, which was 1.019 × 109 m3 with a mean annual baseflow of 1256.23 mm (0. 907 × 109 m3). This constitutes 87.65% of the total flow. It has a mean annual surface runoff of 225.18 mm (0.112 × 109 m3) or 24.4 % of the total discharge. The water resources of the region include surface water and underground water.

Assessment of the Water Resources Carrying Capacity in the Great Dunhuang Region

Water resources carrying capacity(WRCC) is an important index for assessing the coordinated development relationship between population and water resources. The quantitative evaluation of WRCC can provide an important basis for water resource regulation and sustainable economic and social development. Based on the statistical data of cities and counties in the Great Dunhuang Region(GDR), and taking counties as the basic units,this study quantitatively analyzed the WRCC and carrying status of the GDR under different water inflow conditions and policy constraints from 2010 to 2017. The study revealed three main trends.(1) From 2010 to 2017, the WRCC of the GDR increased year by year, from 343700, 315900 and 291100 people to 458700, 415400 and 375600people in normal, dry and extremely dry years, respectively.(2) Under policy constraints, the WRCC of the GDR increased year by year from 309400 people in 2010 to 412400 people in 2017. Based on future estimates, the WRCC of the GDR are expected to be 326600 people in 2020 and 341200 people in 2030.(3) From 2010 to 2017,the water resources carrying index of the GDR was decreasing, and it decreased from 1.05, 1.14 and 1.24 to 0.80,0.88 and 0.97 in normal, dry and extremely dry years, respectively. The carrying status changed from critical overload to balanced. Although the WRCC and the carrying status of the GDR had significantly improved by 2017, the overall upper limit of the carrying capacity is not high. Therefore, efforts should be made to improve the utilization efficiency of water resources in order to maintain the sustainable utilization of water resources in the GDR.

Upstream-downstream linkages of hydrological processes in the Himalayan region

Understanding the upstream-downstream linkages in hydrological processes is essential for water resources planning in river basins.Although there are many studies of individual aspects of these processes in the Himalayan region,studies along the length of the basins are limited.This study summarizes the present state of knowledge about linkages in hydrological processes between upstream and downstream areas of river basins in the Himalayan region based on a literature review.The paper studies the linkages between the changes in the physical environment of upstream areas(land use,snow storage,and soil erosion)and of climate change on the downstream water availability,flood and dry season flow,and erosion and sedimentation.It is argued that these linkages are complex due to the extreme altitudinal range associated with the young and fragile geology,extreme seasonal and spatial variation in rainfall,and diversity of anthropogenic processes.Based on the findings,the paper concludes that integrated systems analysis is required to understand the holistic complexity of upstream-downstream linkages of hydrological processes in the river basin context.The integrated land and water resources management(ILWRM)approach can be instrumental in developing adaptive solutions to problems and can also enable stakeholders of upstream and downstream areas with various interests and needs to work together for the better utilization and management of land and water resources.As a part of this,the specific circumstances of the upstream communities,who live in fragile and inaccessible mountain areas with limited resource opportunities,should be taken into account so that incentive mechanisms can be established to encourage and acknowledge their contribution.