Extreme value analysis of streamflow time series in Poyang Lake Basin, China

Extreme meteorological and hydrological events may cause major disasters and heavy social and economic losses.Therefore,more and more studies have focused on extreme hydro-meteorological events in various climates and geographic regions.Based on nearly 50 years of observed records of the Poyang Lake Basin,the occurrence and changing trends of extreme streamflow indices,including the annual maximum flow,annual peak-over-threshold flows,and low flows,were analyzed for ten hydrological stations.The results indicate that most annual maximum flows occurred from April to July,highly attributed to the Southeast Asian summer monsoons,whereas the annual minimum flows were concentrated between January and February.As for the low flow indices (the annual minimum flow,annual minimum 7-d flow,and annual minimum 30-d flow),a significant increasing trend was detected in most parts of the Poyang Lake Basin.The trends illustrate the potential effects of climate change and human activities on the hydrological cycle over the Poyang Lake Basin.     

朱庄水库流域径流量变化特征及影响因素

利用朱庄区域长系列水文资料,对径流量的年内、年际变化特征及变化趋势进行了分析研究,分析了人类活动影响引起下垫面变化导致径流变化的原因,估算了降水和下垫面变化对径流量的影响量。该区域径流量年内、年际变化较大;多年径流量系列呈减少趋势,尤其从20世纪70年代末以来径流量发生了显著变异;下垫面变化是径流量减少的主要原因。     

北部湾盆地流沙港组湖相烃源岩的差异

北部湾盆地是中国近海重要的富油盆地,油气发现主要集中于涠西南凹陷、乌石凹陷和福山凹陷,探明原油地质储量约为4.05×10⁸t,但各个主要凹陷的探明油气地质储量存在显著差异。北部湾盆地各凹陷的油气富集程度与其湖相烃源岩的差异密切相关,从涠西南凹陷到乌石凹陷,再到迈陈凹陷和福山凹陷,古近系流沙港组烃源岩的品质总体下降,烃源岩的有机质丰度降低,有机质类型从以腐泥型为主变成以混合型占优势,烃源岩的生烃潜力下降。分析表明,尽管北部湾盆地流沙港组烃源岩在形成期各凹陷普遍具有较高的古湖泊有机质生产力,但各凹陷的有机质来源仍然存在差异,有机质保存条件也存在差异,从涠西南凹陷到乌石凹陷,再到迈陈凹陷、福山凹陷和海中凹陷,湖相藻类来源的有机质减少,陆生高等植物来源的有机质增加,有机质保存条件具有变差的趋势。     

浙江省丽水市瓯江水生态系统保护与修复

介绍浙江省丽水市瓯江水生态系统现状,根据瓯江水生态系统保护与修复的目标,提出瓯江水生态系统保护与修复的措施：对土地利用进行分级控制,构建水生态系统安全格局,编制瓯江水生态系统的保护与修复总体规划,分段实施水生态系统保护与修复,开展瓯江水生态系统保护与修复的制度与机制建设。此外,总结了瓯江水生态系统保护与修复工作的成效与存在问题。     

太湖流域蔬菜复合污染及生物富集特征研究

在太湖流域（苏南地区）无锡、常州、镇江3市农业活动区蔬菜及其对应土壤中PAEs化合物和Cd、Zn、Cu、Ni 4种重金属进行检测分析基础上,探讨了蔬菜复合污染分布及污染物的生物富集特征。结果表明,流域蔬菜中PAEs以DMP、DEEP、DNP含量较高,分别为：0.01～10.10mg/kg,ND-8.28mg/kg,ND-2.85mg/kg,重金属以Zn含量最高,为1.86～14.24mg/kg;蔬菜对应土壤中PAEs以DNOP、DMEP、DNP、DMP含量较高,分别为：0.13～44.7mg/kg,0.47～50.42mg/kg,0.48～64.7mg/kg,19.46～533.6mg/kg,重金属也以Zn含量最高,为31.02～43.73mg/kg;蔬菜富集规律分析发现,BMPP、DNHP、DNOP及重金属Cd在蔬菜中的富集系数较大。     

Water Balance of the Upper Jordan River Basin

Sharing water in the Jordan basin has been a key topic in the recent peace talks between Israel and its neighbors. Knowing the quantity of water available is a prerequisite to water sharing. Many different values have been published in recent years. Different sources report Jordan's discharge flow into Lake Kinneret anywhere from 460 to 800 Mm³/year. The aim of this article is to present a water balance for the Jordan basin for a 15-year period. The years 1977–1978 to 1991–1992 were studied for the basin's water budget, as they represent the present day (1998) land use. The results show that Lake Kinneret has a yearly average input (= output) of 770 Mm³. Israel uses some 800 Mcm³/year from the entire Jordan basin, of which 440 Mm³ is used within the basin and the rest outside. There is about 100 Mm³ for future utilization in the watershed. The yearly Jordan's discharge to the Dead Sea is 220–250 Mm³. Reporting by various secondary data sources is compared to primary data findings to illustrate the great variability of data reporting and to provide annual flow estimates, based largely on primary sources, for the Upper Jordan River.     

The deep waters of land reform: land,water and conservation area claims in Limpopo Province,Olifants Basin,South Africa

Through investigating the reactions of commercial farmers to land and water reforms in the Trichardtsdal-Ofcolaco area, Limpopo Province, Olifants Basin, South Africa, from 1997 to 2006, it is shown that water claims are key to land redistribution processes, and that commercial farmers make strategic use of arguments for nature conservation and ecological stewardship to defend their claims to water. Given these observations, caution is warranted with respect to the implementation of land and water reforms as separate policy packages; it may be more effective to design water and conservation policies as an integral part of land reform programmes.     

引黄灌区跨地区水权转让补偿 标准的研究

针对黄河流域引黄灌区的跨地区水权转让补偿标准的定量问题,探讨了转让费用构成中的农业风险补偿、生态补偿、水管单位补偿的含义和计算方法,并以内蒙古自治区鄂尔多斯市引黄灌区的水权转让一期项目为实例,通过计算得出3项补偿费用为889.92万元/年,在25年水权转让期内应付出的补偿费用为22 248万元,水的转让价格平均增加补偿费用为3.45元/m3。对黄河流域水权转让费用构成中的补偿费用进行准确的定量计算,将会进一步推动水权转让更加科学合理的实施,并为引黄灌区的健康持续发展奠定基础。     

Changes of Pan Evaporation in the Recent 40 Years in the Yellow River Basin

Abstract

Based on monitoring data of 123 meteorological stations from 1960 to 2000 near or in the Yellow River Basin, the spatial and temporal distributions and their trends for pan evaporation (PE) are investigated in this study. The results indicate that, despite the annual mean air temperature over the Yellow River Basin has, on average, increased by 0.6° over the past 40 years, the rate of PE has steadily decreased, especially in summer and spring. Compared with the period of 1960s to 1970s, the rate of annual pan evaporation during 1980s to 1990s has decreased by 126mm or 7.0 percent. Spatial distribution of the rate of change show that this kind of trend is general but not universal, PE has significantly decreased over the upper and lower reaches of the Yellow River, but increased to a small degree over the middle reaches. Further analyses show that the decrease of PE is mainly related to reductions in sunshine durations and solar irradiance, owing to more clouds and aerosols.