沐川县水源涵养能力变化研究

本研究基于多年多源数据,采用水量平衡法计算出沐川县多年水源涵养量,利用线性回归分析得到了沐川县的水源涵养能力变化情况。研究表明:沐川县水源涵养能力变化较大,中西部区域水源涵养能力明显增强,东北区域偏北方向水源涵养能力呈现下降趋势,中东部区域水源涵养能力呈现减弱趋势,中部区域及东南部分区域水源涵养能力呈现明显减弱趋势。整体来看,区域内水源涵养能力增强区域略多于减弱区域。主成分分析方法显示,研究区水源涵养变化的首要驱动因素为高程,可以看作植被涵养水源能力,次要驱动力为降水量、植被覆盖度和地表温度,可以看作水分的流动分布情况。

水源更换对自来水厂进水泵房给水泵的影响

以杭州市清泰水厂进水泵房给水泵为对象,通过对千岛湖作为第二供应水源后水质变化进行理论分析和试验研究,以及水源变化后水泵实际流量扬程等性能进行分析研究,提出在千岛湖、钱塘江等多水源下给水泵的选型设计。通过给水泵叶轮切削的方式,使给水泵新的工况点处于高效区域内,确保给水泵安全顺利生产运行,提高进水泵房给水泵的效率,满足日供水量的要求。

地震对城镇供水水源水质影响及应对措施研究

地震常常造成严重的人员和动植物伤亡，同时，因地震引发的山体滑坡、泥石流等次生地质灾害，以及灾后防疫工作需要使用的消毒剂在土壤中的积累和释放，都将可能对地震灾区城镇供水水源水质造成严重影响，在常规处理工艺下，城镇供水水质很难满足《生活饮用水卫生标准》GB5749-2006标准要求，因此，研究地震灾区城镇供水水源水质变化情况及应对措施，对于保障灾区城镇供水安全具有十分重要的意义。文章以“5·12”汶川特大地震受影响的若干城镇供水水源为例，分别从不同季节、不同河流类别对浊度、氨氮和耗氧量等指标在震前、震后及地震期间的变化情况进行分析研究，归纳其变化规律，为地震灾区城镇供水厂处理工艺的完善与改进提供应急处理技术支持。

水源更换对自来水厂进水泵房给水泵的影响

随着城镇化进程的加快,我国重要基础设施建设取得了显著的成效。水资源的地位及其重要性愈发明显的展现出来,自来水厂水资源供应作为城市居民生活用水的重要来源,与人们的日常生活息息相关,其能够提供高效、稳定及安全的水资源供应,将极大的影响人们生活质量的提升,自来水厂出水泵房在水资源供应方面,其采取的是传统的由调度室统一调度的水资源供应模式,然而该模式在水资源供应过程中会产生较大的能耗损失,同时其在应对水资源供应相关突发事件的能力较为低下,因而其往往会引发水资源的供应不够安全稳定的缺陷,而分级调度模式则能有效的弥补这一缺陷,不仅能保障自来水厂水资源供应的安全性及稳定性,还能极大的降低其在供应过程中引发的巨大能耗损失,因而对自来水厂水资源供应效率的提高发挥关键作用。本文就水源更换对自来水厂进水泵房给水泵的影响展开探讨。

2000-2020年丹江口水库(河南部分)水体面积数据集

丹江口水库作为南水北调中线工程水源,利用遥感影像对水库边界进行长时间序列动态变化监测,对于保障南水北调调水量具有重要意义。本研究采用多时相Landsat遥感影像集,通过修正的归一化差异水指数(m NDWI)、增强植被指数(EVI)和归一化差异植被指数(NDVI)之间的关系,基于Google Earth Engine云平台获取了长时间序列的丹江口水库地表水体空间数据集。本数据集包括了2000–2020年21期丹江口水库水体空间数据,可以为研究丹江口水库水体时空变化提供依据,也可以作为研究该区域气候变化、生态环境变化的基础数据。

明代前期黄河南泛与贾鲁河的形成

明代前期采取“北堤南分”的治黄策略。在这一策略的指导下,黄河在河南境内出现过数条南下入淮泛道,贾鲁河即是其中之一。贾鲁河是在正统二年黄泛通道孙家渡河上初步形成的,经刘大夏疏浚后,与元代贾鲁大河互为表里,分泄黄河来水,行河时间近百年之久,故又有“小黄河”之称。明正德以后,治黄策略由分流治河变为“筑堤束水,以水攻沙”。在治黄方略转变影响下,贾鲁大河主流逐渐归于一槽,黄河南泛通道基本断绝,贾鲁河分黄河水南下的历史宣告结束。贾鲁河的水源构成随之发生改变,水量丰沛的嵩阴山地诸山泉水、双洎河汇入贾鲁河,改善了贾鲁河的水运条件,促进流域沿岸明清商业市镇的兴起与繁荣。

稳定氢氧同位素定量植物水分来源的不确定性解析

稳定氢氧同位素技术被广泛运用于生态系统、特别是干旱区生态系统中植物水分来源的研究,其理论假设为"水分被植物根系吸收并向木质部运输过程中不发生氢氧同位素分馏"。生态系统中不同水源的氢氧同位素组成普遍存在显著差异,为从水源混合体中区分出各水源的贡献率提供了前提条件。但在实际应用过程中,诸多因素导致稳定氢氧同位素技术定量植物水分来源的结果具有不确定性。综合已有研究并加以分析,举证说明植物吸收水分相对于水源同位素变化的滞后性、水源同位素的季节性变化、蒸发作用和水源之间的混合作用对水源同位素的影响等导致植物水分来源定量结果不确定性的几个因素,以期为今后稳定氢氧同位素技术在植物水分来源领域的应用提供参考。

Coordination of Urbanization and Water Ecological Environment in Shayinghe River Basin,China

During the rapid industrialization and urbanization of China,urban agglomeration in river basin areas raises the problems of over-use of water resources and pollution of the water environment.Related research in China has mainly focused on the conflicts among economic growth,urban expansion and water resource shortages within admin-istrative boundaries.However,water environments are much more dependent on their physical boundaries than their administrative boundaries.Consistent with the nature of water environment,this study aims at analyzing coordination relationships between urban development and water environment changes within physical river basin boundaries.We chose the Shayinghe River Basin,China,as our case study area which is facing serious challenges related to water en-vironment protection.Then we classified 35 county-level administrative units into upstream,midstream and down-stream regions based on their physical characteristics;analyzed the coordination degree of urban agglomeration using the Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) method;and constructed cooperative models using the Linear Programming (LP function) to simulate four scenarios of the coordination relationship be-tween urban population increase and water environment protection based on existing water resources and water pollu-tion data.The results show that the present coordinative situation in Shayinghe River Basin is not sustainable.In gen-eral,more than 50% administrative units are in the bad coordinative situation.In particular,the downstream region is under worse condition than the upstream and midstream regions.Cooperative models in scenario analyses indicate that the population scale set in existing urban master plannings is not coordinated with the water environment protection.To reach the goal of regional sustainable development,the total population needs to be controlled such that it will re-main at 4.5×10 7 or below by 2020 given the capacity of water environment.

Water Security Problem in North China: Research and Perspective

This paper addresses the emergence of water security problems in North China with the aim of highlighting key waterresources management and water security issues for the long-term development of North China. Three key problemsrelated to water resources and security issues in North China in the 21st century are addressed, namely 1) the watercycle under environmental change, 2) agricultural water saving, and 3) water security. Development of internationalresearch related to these issues is also reviewed. The research plan developed recently by the Chinese Academy of Sciences(CAS) is discussed and suggestions on research and development of water resources science in North China are presented.Thanks to focus on experimental catchments and dedicated research stations, a detailed knowledge of the water cycle onNorth China farmland has been compiled. A range of techniques that include isotope tracers has been used to acquirehydrologic data. Much research has been devoted to developing distributed hydrological models at different scales. In thewell irrigation district, five different water saving irrigation regimes have been investigated, and these regimes have hadwidespread application, and reduced water use 60-150 mm while they increased water use efficiency (WUE) by 20%-30%.Furthermore, preventing water pollution is the most essential step to ensure North China’s water security.

The Role of Hydropower in Climate Change Mitigation and Adaptation： A Review

Hydropower is a clean,renewable,and environmentally friendly source of energy.It produces 3930(TW·h)·a–1,and yields 16% of the world's generated electricity and about 78% of renewable electricity generation(in 2015).Hydropower and climate change show a double relationship.On the one hand,as an important renewable energy resource,hydropower contributes significantly to the avoidance of greenhouse gas(GHG) emissions and to the mitigation of global warming.On the other hand,climate change is likely to alter river discharge,impacting water availability and hydropower generation.Hydropower contributes significantly to the reduction of GHG emissions and to energy supply security.Compared with conventional coal power plants,hydropower prevents the emission of about 3 GT CO2 per year,which represents about 9% of global annual CO2 emissions.Hydropower projects may also have an enabling role beyond the electricity sector,as a financing instrument for multipurpose reservoirs and as an adaptive measure regarding the impacts of climate change on water resources,because regulated basins with large reservoir capacities are more resilient to water resource changes,less vulnerable to climate change,and act as a storage buffer against climate change.At the global level,the overall impact of climate change on existing hydropower generation may be expected to be small,or even slightly positive.However,there is the possibility of substantial variations across regions and even within countries.In conclusion,the general verdict on hydropower is that it is a cheap and mature technology that contributes significantly to climate change mitigation,and could play an important role in the climate change adaptation of water resource availability.However,careful attention is necessary to mitigate the substantial environmental and social costs.Roughly more than a terawatt of capacity could be added in upcoming decades.

Vulnerability assessment of water resources to climate change in Chinese cities

Climate change is an inevitable trend,which challenges security of water resources in China,especially in cities.Assessing vulnerability of water resource to climate change in cities has important role for policy makers. The paper constructs a vulnerability function,including exposure,sensitivity and adaptive capacity,according to the vulnerability concept proposed by IPCC,establishes an assessment indicators system of water resources to climate change in cities,and analyzes vulnerability features of Chinese cites based on 655 cities＇data in 2006.The vulnerability assessment results show that there are distinctive differences among all the cities,between east,central and west cities,between ordinary,big and mega cities,while there is no statistical significant difference between north and south cities.Based on the research,the paper suggests that strategic emphasis should focus on the central cities and ordinary cities

Impacts of Climate Change on Water Resources in Diyala River Basin, Iraq

Diyala River is the third largest tributary of the Tigris River running 445 km length and draining an area of 32,600 km2. The river is the major source of water supply for Diyala City for municipal, domestic, agriculture and other purposes. Diyala River Basin currently is suffering from water scarcity and contamination problems. Up-to-date studies have shown that blue and green waters of a basin have been demonstrating increasing variability contributing to more severe droughts and floods seemingly due to climate change. To obtain better understanding of the impacts of climate change on water resources in Diyala River Basin in near 2046-2064 and distant future 2080~2100, SWAT （soil and water assessment tool） was used. The model is first examined for its capability of capturing the basin characteristics, and then, projections from six GCMs （general circulation models） are incorporated to assess the impacts of climate change on water resources under three emission scenarios： A2, AIB and B1. The results showed deteriorating water resources regime into the future.

Impacts of climate change on agricultural water resources and adaptation on the North China Plain

Climate change is having a considerable impact on the availability of water resources for agricultural production on the North China Plain （NCP）, where the shortage of water is currently disturbing the stability and sustainability of agricultural production with respect to the drying tendency since the 1950s. However, although potential evapotranspiration （ET） has shown a decreasing trend under climate change, actual ET has slightly increased with an acceleration in hydrological cycling. Global climate model （GCM） ensemble projections predict that by the 2050s, the increased crop water demand and intensified ET resulting from global warming will reduce water resources surplus （Precipitation-ET） about 4%-24% and increase significantly the irrigation water demand in crop growth periods. This study assesses possible mitigation and adaptation measures for enabling agricultural sustainability. It is revealed that reducing the sowing area of winter wheat （3.0%-15.9%） in water-limited basins, together with improvement in crop water-use efficiency would effectively mitigate water shortages and intensify the resilience of agricultural systems to climate change.

Sustainable development of Shandong Peninsula urban agglomeration:a scenario analysis based on water shortage and water environment changes

China has experienced a rapid urbanization since late 1970s. The great increase of urban population has resulted in various environmental changes, of which urban water shortage and water environment problems have occurred in most cities, especially in the rapidly developing urban agglomerations in the eastern coastal region. This research, taking Shandong Peninsula Urban Agglomeration （SPUA） as a case study area analyzes the urbanization expansion in the last decades, discusses the water shortage and water environment changes following the rapid economic development and urbanization sueh as groundwater sinking in the urban and plain area, sea water and saltwater intrusion in the coastal cities, water pollution overspreading and water ecosystem degradation, and puts forwards some strategies for sustainabilitv in populous regions with severe water shortage. Some countermeasures for sustainable development of SPUA are put forward, such as constructing modern water resources inter-city networks to regulate water resouree between cities, adjnsting urbanization policy and urban scale planning to promote the development of small towns and medium sized cities, optimizing urban industry structure by restricting high water consumption enterprises and stimulating the growth of tertiary industry. improving water use efficiency to rednce fresh water consumption and wastewater discharge, introducing economic means to water pricing and water management system, and restoring ecological conditions to strengthen the natural water-making capacity.

Key Issues on Cryospheric Changes,Trends and Their Impacts

On the basis of analyzing the importance of cryospheric researches in China and current status of cryospheric sciences in the world, this paper addresses key issues and main contents of present cryospheric sciences in China. The key issues currently addressed are： i） mechanisms of different types of glaciers in response to climate change and the scale-conversion in water resources assessments; ii） modeling of water and heat exchanges between frozen soil and vegetation; iii） parameterization of physical processes in cryosphere as well as coupling with climate models. To gain full clarification of these key issues, works of the following three aspects should be highlighted, i.e., cryospheric processes and responses to climate change, influences of cryospheric changes, and adaptation strategies for cryospheric changes.

Assessing Spatio-temporal Characteristics of Water Storage Changes in the Mountainous Areas of Central Asia Based on GRACE

The mountainous areas of Central Asia provide substantial water resources, and studying change in water storage and the impacts of precipitation and snow cover in the mountain ranges of Central Asia is of the greatest importance for understanding regional water shortages and the main factors. Data from the GRACE （Gravity Recovery and Climate Experiment） satellites, precipitation prod- ucts and snow-covered area data were used to analyze the spatio-temporal characteristics of water storage changes and the effects of precipitation and snow cover from April 2002 to December 2013. The results were computed for each mountain ranges, and the follow- ing conclusions were drawn. The water storage in the mountainous areas of Central Asia as a whole increases in summer and winter, whereas it decreases in autumn. The water storage is affected by precipitation to some extent and some areas exhibit hysteresis. The area of positive water storage changes moves from west to east over the course of the year. The water storage declined during the period 2002-2004. It then returned to a higher level in 2005-2006 and featured lower levels in 2007-009 Subsequently, the water storage increased gradually from 2010 to 2013. The Eastern Tianshan Mountains and Western Tianshan Mountain subzones examined in this study display similar tendencies, and the trends observed in the Karakorum Mountains and the Kunlun Mountains are also similar. However, the Eastern Tianshan Mountains and Western Tianshan Mountains were influenced by precipitation to a greater degree than the latter two ranges. The water storage in Qilian Mountains showed a pronounced increasing trend, and this range is the most strongly affected by precipitation. Based on an analysis of all investigated subzones, precipitation has the greatest influence on total water storage relative to the snow covered area in some areas of Central Asia. The results obtained from this study will be of value for scientists stud- ying the mechanisms that influence changes in water storage in Central Asia.

Climate Change Impacts on Water Resources in Yemen

Climate change impacts on water resources are expected to be significant in Yemen. Efforts have been made to understand the expected changes and develop mitigation possibilities for the expected scenarios for a future sustainable use of resources and mitigation of expected impacts. The paper describes the development of a detailed baseline database and the assessment of climate change and variability impacts on water resources over the 2030, 2050 and 2080 time horizon on a Yemen-wide scale. Based on downscaled Global Climate Model data, a range of scenarios were established, representing potential Mean, Warm ＆ Wet and Hot ＆ Dry conditions as derived by evaluating worst case scenarios from the ensemble of the global models for the specified years. The results of the model include an estimated runoff coefficient, monthly rainfall, runoff, infiltration and evaporation representing the water balance in the different catchments. Analysis of the different evaluated scenarios shows that in the Mid, Warm and Wet scenario the hydrological components are generally higher than in the baseline scenario. For the Hot ＆ Dry scenario, runoff, infiltration and evapotranspiration are decreasing due to the decreasing precipitation and increase in temperature. The relative changes in runoff are strongest.

Climate change and water resources： Case study of Eastern Monsoon Region of China

This paper addresses the impact of climate change on the water cycle and resource changes in the Eastern Monsoon Region of China （EMRC）. It also represents a summary of the achievements made by the National Key Basic Research and Development Program （2010CB428400）, where the major research focuses are detection and attribution, extreme floods and droughts, and adaptation of water resources management. Preliminary conclusions can be summarized into four points： 1） Water cycling and water resource changes in the EMRC are rather complicated as the region is impacted by natural changes relating to the strong monsoon influence and also by climate change impacts caused by CO2 emissions due to anthropogenic forcing; 2） the rate of natural variability contributing to the influence on precipitation accounts for about 70%, and the rate from anthropogenic forcing accounts for 30% on average in the EMRC. However, with future scenarios of increasing CO2 emissions, the contribution rate from anthropogenic forcing will increase and water resources management will experience greater issues related to the climate change impact; 3） Extreme floods and droughts in the EMRC will be an increasing trend, based on IPCC-AR5 scenarios; 4） Along with rising temperatures of 1 ~C in North China, the agricultural water consumption will increase to about 4% of total water consumption. Therefore, climate change is making a significant impact and will be a risk to the EMRC, which covers almost all of the eight major river basins, such as the Yangtze River, Yellow River, Huaihe River, Haihe River, and Pearl River, and to the South-to-North Water Diversion Project （middle line）. To ensure water security, it is urgently necessary to take adaptive countermeasures and reduce the vulnerability of water resources and associated risks.

Impact of Meteorological Drought on Streamflow Drought in Jinghe River Basin of China

Under global climate change, drought has become one of the most serious natural hazards, affecting the ecological environment and human life. Drought can be categorized as meteorological, agricultural, hydrological or socio-economic drought. Among the different categories of drought, hydrological drought, especially streamflow drought, has been given more attention by local governments, researchers and the public in recent years. Identifying the occurrence of streamflow drought and issuing early warning can provide timely information for effective water resources management. In this study, streamflow drought is detected by using the Standardized Runoff Index, whereas meteorological drought is detected by the Standardized Precipitation Index. Comparative analyses of frequency, magnitude, onset and duration are conducted to identify the impact of meteorological drought on streamflow drought. This study focuses on the Jinghe River Basin in Northwest China, mainly providing the following findings. 1) Eleven meteorological droughts and six streamflow droughts were indicated during 1970 and 1990 after pooling using Inter-event time and volume Criterion method. 2) Streamflow drought in the Jinghe River Basin lagged meteorological drought for about 127 days. 3) The frequency of streamflow drought in Jinghe River Basin was less than meteorological drought. However, the average duration of streamflow drought is longer. 4) The magnitude of streamflow drought is greater than meteorological drought. These results not only play an important theoretical role in understanding relationships between different drought categories, but also have practical implications for streamflow drought mitigation and regional water resources management.

Climate Change Impacts on Water Resources of Greater Zab River, Iraq

Greater Zab is the largest tributary of the Tigris River in lraq where the catchment area is currently being plagued by water scarcity and pollution problems. Contemporary studies have revealed that blue and green waters of the basin have been manifesting increasing variability contributing to more severe droughts and floods apparently due to climate change. In order to gain greater appreciation of the impacts of climate change on water resources in the study area in near and distant future, SWAT （Soil and Water Assessment Tool） has been used. The model is first tested for its suitability in capturing the basin characteristics, and then, forecasts from six GCMs （general circulation models） with about half-a-century lead time to 2046-2064 and one-century lead time to 2080-2100 are incorporated to evaluate the impacts of climate change on water resources under three emission scenarios： A 1 B, A2 and BI. The results showed worsening water resources regime into the future.