Spatio-temporal distribution of phytoplankton in the Danjiangkou Reservoir, a water source area for the South-to-North Water Diversion Project (Middle Route), China

One of the water source areas of the South-to-North Water Diversion Project is the Danjiangkou Reservoir (DJKR). To understand seasonal variation in phytoplankton composition, abundance and distribution in the DJKR area before water diversion, as well as to estimate potential risks of water quality after water diversion, we conducted an investigation on phytoplankton in the DJKR from August 2008 to May 2009. The investigation included 10 sampling sites, each with four depths of 0.5, 5, 10, and 20 m. In this study, 117 taxa belonging to 76 genera were identified, consisting of diatoms (39 taxa), green algae (47 taxa), blue-green algae (19 taxa), and others (12 taxa). Annual average phytoplankton abundance was 2.01×106 ind./L, and the highest value was 14.72 × 106 ind/L (at site 3 in August 2008). Phytoplankton abundance in front of the Danjiangkou Dam (DJKD) was higher than that of the Danjiang Reservoir Basin. Phytoplankton distribution showed a vertical declining trend from 0.5 m to 20 m at most sites in August 2008 (especially at sites of 1, 2, 4 and 10), but no distinct pattern in other sampling months. In December 2008 and March 2009, Stephanodiscus sp. was the most abundant species, amounting to 55.23% and 72.34%, respectively. We propose that high abundance of Stephanodiscus sp. may have contributed greatly to the frequent occurrence of Stephanodiscus sp. blooms in middle-low reaches of the Hanjiang River during the early spring of 2009. In comparison with previous studies conducted from 1992 to 2006, annual average phytoplankton density, green algae and blue-green algae species, as well as major nutrient concentrations increased, while phytoplankton diversity indices declined. This indicates a gradual decline in water quality. More research should be conducted and countermeasures taken to prevent further deterioration of water quality in the DJKR.

Optimization and coordination of South-to-North Water Diversion supply chain with strategic customer behavior

The South-to-North Water Diversion （SNWD） Project is a significant engineering project meant to solve water shortage problems in North China. Faced with market operations management of the water diversion system, this study defined the supply chain system for the SNWD Project, considering the actual project conditions, built a decentralized decision model and a centralized decision model with strategic customer behavior （SCB） using a floating pricing mechanism （FPM）, and constructed a coordination mechanism via a revenue-sharing contract. The results suggest the following： （1） owing to water shortage supplements and the excess water sale policy provided by the FPM, the optimal ordering quantity of water resources is less than that without the FPM, and the optimal profits of the whole supply chain, supplier, and external distributor are higher than they would be without the FPM; （2） wholesale pricing and supplementary wholesale pricing with SCB are higher than those without SCB, and the optimal profits of the whole supply chain, supplier, and external distributor are higher than they would be without SCB; and （3） considering SCB and introducing the FPM help increase the optimal profits of the whole supply chain, supplier, and external distributor, and improve the efficiency of water resources usage.

Reliability model of organization management chain of South-to-North Water Diversion Project during construction period

In order to analyze the indispensability of the organization management chain of the South-to-North Water Diversion Project （SNWDP）, two basic forms （series connection state and mixed state of both series connection and parallel connection） of the organization management chain can be abstracted. The indispensability of each form has been studied and is described in this paper. Through analysis of the reliability of the two basic forms, reliability models of the organization management chain in the series connection state and the mixed state of both series connection and parallel connection have been set up.

Critical chain construction with multi-resource constraints based on portfolio technology in South-to-North Water Diversion Project

Recently, the critical chain study has become a hot issue in the project management research field. The construction of the critical chain with multi-resource constraints is a new research subject. According to the system analysis theory and project portfolio theory, this paper discusses the creation of project portfolios based on the similarity principle and gives the definition of priority in multi-resource allocation based on quantitative analysis. A model with multi-resource constraints, which can be applied to the critical chain construction of the A-bid section in the South-to-North Water Diversion Project, was proposed. Contrast analysis with the comprehensive treatment construction method and aggressive treatment construction method was carried out. This paper also makes suggestions for further research directions and subjects, which will be useful in improving the theories in relevant research fields.

Wet-Dry Runoff Correlation in Western Route of South-to-North Water Diversion Project,China

The Western Route of the South-to-North Water Diversion Project is an important trans-basin diversion project to transfer water from the upstream Yangtze River and its tributaries(water-exporting area), to the upstream of the Yellow River(waterimporting area). The long-term hydrological data from 14 stream gauging stations in the Western Route area and techniques including the pre-whitening approach, non-parametric test, Bayes, law, variance analysis extrapolation, and Wavelet Analysis are applied to identify the streamflow characteristics and trends, streamflow time series cross-correlations, wetness-dryness encountering probability, and periodicities that occurred over the last 50 years. The results show that the water-exporting area, waterimporting area, and the stretch downstream of the water-exporting have synchronization in high–low flow relationship, whereas they display nonsynchronization in long-term evolution. This corresponds to the complicated and variable climate of the plateau region. There is no obvious increasing or decreasing trend in runoff at any gauging station. The best hydrological compensation probability for rivers where water is diverted is about 25% to 10%, and those rivers influenced significantly by diversion are the Jinsha and Yalong rivers. Proper planning and design of compensation reservoirs for the water-exporting area and stretch downstream of the waterexporting area can increase the hydrological compensation possibility from water-exporting area to the water-importing area, and reduce the impact on the stretch of river downstream of the waterexporting area.

Land Cover Changes and Drivers in the Water Source Area of the Middle Route of the South-to-North Water Diversion Project in China from 2000 to 2015

The Middle Route of the South-to-North Water Diversion Project(MR-SNWDP)in China,with construction beginning in 2003,diverts water from Danjiangkou Reservoir to North China for residential,agriculture and industrial use.The water source area of the MR-SNWDP is the region that is most sensitive to and most affected by the construction of this water diversion project.In this study,we used Landsat Thematic Mapper(TM)and HJ-1 A/B images from 2000 to 2015 by an object-based approach with a hierarchical classification method for mapping land cover in the water source area.The changes in land cover were illuminated by transfer matrixes,single dynamic degree,slope zones and fractional vegetation cover(FVC).The results indicated that the area of cropland decreased by 31%and was replaced mainly by shrub over the past 15 years,whereas forest and settlements showed continuous increases of 29.2% and 77.7%,respectively.The changes in cropland were obvious in all slope zones and decreased most remarkably(–43.8%)in the slope zone above 25°.Compared to the FVC of forest and shrub,significant improvement was exhibited in the FVC of grassland,with a growth rate of 16.6%.We concluded that local policies,including economic development,water conservation and immigration resulting from the construction of the MR-SNWDP,were the main drivers of land cover changes;notably,they stimulated the substantial and rapid expansion of settlements,doubled the wetlands and drove the transformation from cropland to settlements in immigration areas.

Penalty model for delay of bidding section construction period in South-to-North Water Diversion Eastern Route Project from perspective of programs

According to the multi-project and program management theory, this paper analyzes the program generation principle and establishes a program based on progress goals. On the basis of the present situation of calculation of penalty for delay of the bidding section construction period with the critical path method, we studied the effects of contractor-induced delay of the bidding section construction period in detail, including the effects on the construction period of the bidding section itself, the earliest start times of the next bidding section and other subsequent bidding sections, and the construction period of the program, and then constructed a penalty model for delay of the bidding section construction period from the perspective of programs. Using the penalty model, we conducted a practical analysis of penalty for delay of the construction period of the Baoying station program in the South-to-North Water Diversion Project. The model can help determine the amount of penalty for delay of the construction period in bidding sections scientifically and reasonably,

IMPACTS OF THE SOUTH-TO-NORTH WATER DIVERSION PROJECTS (MIDDLE ROUTE)ON THE WATER ENVIRONMENT OF THE MIDDLE AND LOWER REACHES OF THE HANJIANG RIVER

In this paper, according to the rule of unbalanced sediment transport and the analysis of field data, different water diversion schemes were theoretically studied, including the erosion and sedimentation trend as well as their impacts on the environment of the middle and lower reaches of the Hanjiang River. The results showed that the 95×10 8m 3 water diversion scheme will cause less erosion and water level decrease than the 15×10 8m 3 water diversion scheme. Using a water diversion scheme of 95×10 8m 3, the decrease of water quantity can impact the river hydrodynamic regime substantially and the environments of the middle and lower reaches of the Hanjiang River will be greatly affected. It is therefore necessary to develop new water resources or build projects to meet the need of the environment and the needs for navigation.

Impact of the eastern water diversion from the south to the north project on the saltwater intrusion in the Changjiang Estuary in China

The south to the north project (WDP) on the saltwater intrusion in the Changjiang Estuary is studied by the improved three-dimensionai (3D) numerical model.The net unit width flux in the Changjiang Estuary as well as the sectional salt flux is calculated in the North Branch (NB),the South Branch (SB),the North Channel (NC),the South Channel (SC),the North Passage (NP) and the South Passage (SP),respectively.The net seaward water flux in the SB is reduced,and the net water flux spilling over from the NB to the SB is enhanced after the eastern WDP.Under the mean river discharge condition in the dry season,the net salt flux spilling over from the NB to the SB is increased by 2.09 t/s and 0.52 t/s during the spring and neap tides,respectively,due to the eastern WDP.The saltwater intrusion in the Changjiang Estuary is enhanced by the eastern WDP.Compared with that during the spring tide,the net water diversion ratio during the neap tide in the NC is smaller,and thus the enhancement of the saltwater intrusion by the eastern WDP is smaller in the NC,and larger in the NP and the SP.The tidally averaged surface salinity at the water intakes of the Dongfengxisha Reservoir,the Chenhang Reservoir and the Qingcaosha Reservoir rises both during the spring and neap tides.

基于πPS-FBG传感技术的激光超声水下铝板缺陷检测研究

为实现水下金属构件在线服役状态的在线评估,搭建了一套基于激光超声和π相移光纤布拉格光栅(πPS-FBG)的水下板材缺陷检测系统.为了研究水下激光超声传播规律,以6061铝合金板材为测试样品,进行了不同水深下的激光超声探测实验.与空气中超声传播相比,实验发现水下πPS-FBG多接收到一个超声波信号,此信号是激光第一次与水面作用产生的纵波信号.随着激励源与πPS-FBG传感距离的增加,超声信号在时域上也延迟增加;πPS-FBG接收的激光激励的首个超声波信号的波速为2871.91 m/s,缺陷反射波的波速为2911.02 m/s,其与铝板中超声表面波的速度接近,两者的相对误差分别为1.3%和0.03%.改变激励源与缺陷的距离,发现缺陷的定位精度与缺陷距离无关,缺陷位置的定位相对误差随着距离的增大而逐渐减小.本研究为水下金属构件的在线服役状态检测提供了一种潜在应用技术(包括在南水北调工程中),对于提高水下结构的安全性和可靠性具有一定意义.

The variation of DOM during long distance water transport by the China South to North Water Diversion Scheme and impact on drinking water treatment

In this study,samples were taken from three locations,upstream to downstream,along the central route project of the China South to North Water Diversion(SNWD)scheme in summer and winter.These were used to reveal the variations of dissolved organic matter(DOM)during the water transfer process,and the effects of these variations on drinking water treatment and disinfection by-products formation potential(DBPs-FP).The results showed that polysaccharides accumulate in summer and reduce in winter with flow distance,which has an important effect on the overall properties of DOM,as well as on the performance of coagulation,ultrafiltration,and the formation of DBPs.Humic substances,and their hydrophilic content,also increased in summer and decreased in winter with flow distance.In contrast,the concentration of small organic substances(MW≤1000 Da)increased in both summer and winter with flow distance,which affected both nanofiltration(NF)membrane fouling and DBPs-FP.The results provide a useful case study of spatial and temporal changes in raw water DOM during long distance water transfer and their impact on the treatment and quality of drinking water from the SNWD.

南水北调中线工程高填方渠道PS-InSAR形变监测

南水北调工程在缓解我国北方地区的水资源紧张状况与改善当地环境方面发挥了重要作用,作为国之重器,保障其安全运营是南水北调工程的重中之重。利用PS-InSAR技术,对2016年10月—2017年6月间南水北调中线工程叶县文庄村高填方渠道进行形变监测。结果表明,渠道东岸约1 km的边坡存在明显变形,最大形变量达到36 mm。对渠道东岸和4个重点监测断面进行纵横断面分析,发现渠道东岸呈现整体性不均匀沉降,且越靠近水域,渠道变形越大,反之则越小。进一步将PS-InSAR监测结果与二等水准数据对比验证,两者超过87%的均方根误差小于±2 mm,且在形变趋势和量值上均高度一致。本研究可为以高填方、深挖方为特征的南水北调渠道安全监测及灾害防治提供可靠的技术支持。

南水北调中线工程水源区耕地面源污染治理农户参与意愿研究--以南阳市为例

南水北调中线工程水源区耕地面源污染治理不仅要依靠先进的科学技术,还需要农户的积极参与。采用TPB理论构建水源区耕地面源污染治理农户参与意愿理论分析框架,剖析农户参与意愿的影响因素并提出研究假说;构建结构方程模型,利用问卷调研收集数据,对水源区耕地面源污染治理农户参与意愿进行实证检验。研究结果表明,水源区耕地面源污染治理农户参与意愿较高,行为态度、主观规范、知觉行为控制等潜变量对农户参与意愿均存在正向影响,且潜变量之间也存在相关关系。因此,建议加大水源区耕地面源污染治理重要性的宣传力度,提升农户对于耕地面源污染的认知程度,增加农户的经济收入,增强地方政府的支持力度,多渠道提升水源区耕地面源污染治理的农户参与意愿。

Computing payment for ecosystem services in watersheds: An analysis of the Middle Route Project of South-to-North Water Diversion in China

Payment for ecosystem services （PES） has attracted considerable attention as an economic incentive for promoting natural resource management recently. As emphasis has been placed on using the incentive-based mechanism by the central government, rapid progress on PES research and practice has been achieved. However PES still faces many difficulties. A key issue is the lack of a fully-fledged theory and method to clearly define the design scope, accounting and feasibility of PES criteria. An improved watershed criteria model was developed in light of research on PES practices in China, investigations on the water source area for the Middle Route Project of South-to-North Water Diversion and ecosystem services outflows theory. The basic principle of assessment is the direct and opportunity cost for ecological conservation and environmental protection in the water source area deduct nationally-financed PES and internal effect. Then the scope and the criteria methods were determined, and internal effect was put forward to define benefits brought from water source area. Finally, Shiyan City, which is the main water source area for the Project of Water Diversion, was analyzed by this model and its payment was calculated. The results showed that： （1） during 2003–2050, the total direct cost and opportunity cost would reach up to 262.70 billion and 256.33 billion Chinese Yuan （CNY, 2000 constant prices）, i.e., 50.61% and 49.38% of total cost, respectively; （2） Shiyan City would gain 0.23, 0.06 and 0.03 CNY/m3 in 2014–2020, 2021–2030, and 2031–2050, respectively.

Potential Ecological Benefits of the Middle Route for the South-North Water Diversion Project

This paper presents a study of the middle route of the South-North Water Diversion Project. The middle route runs through the Northern China plain, where the water shortages are the most severe. There is not only a shortage of water for human usage, but also a shortage of ecological water. Although the current plan for the middle route is strictly focused on supplying water for residential and industrial use, the water can also potentially be used for ecological purposes. This paper evaluates the potential ecological benefits that can be brought to the fragile ecology in northern China by the middle route, in addition to the water supplied to residences and industry. The study describes ecological benefits of the middle route project, such as mitigation of groundwater extraction in the region and positive influences on the climate, the ecological uses of the middle route project itself, such as creating artificial niches along the channel and directly using the channel for ecological purposes, and the ecological uses of the water along the middle route such as diversion of the water into dyer channels that have suffered from drought conditions for decades.

郑州段南水北调水微絮凝-直接过滤试验研究

以南水北调水为原水、聚合氯化铝(PAC)为混凝剂,进行微絮凝-直接过滤的中试试验。运用浊度仪、紫外分光光度计等对过滤前后水的浊度、UV_(254)、COD_(Mn)、NH_3-N和残余铝浓度进行检测,以确定PAC的最佳投加量,同时观察不同PAC投加量下滤柱内水头上涨幅度随时间的变化情况。结果表明:南水北调水河南受水区微絮凝-直接过滤工艺的PAC最佳投加量为24 mg/L,此时对浊度、COD_(Mn)、UV_(254)和NH_3-N的去除率分别为45.0%、59.3%、28.1%、80.0%,残余铝浓度未超标;该PAC投加量下,滤柱的反冲周期缩短为9 h,且滤柱内水头增长幅度与过滤时间呈线性关系。

流固耦合系统的位移-压力(u_i,p)格式在U型渡槽抗震分析中的应用研究

针对大型U型渡槽槽形特征和抗震设计问题,建立了适于U型渡槽流固耦合(FSI)系统动力分析的位移-压力(ui,p)有限元格式,给出流固耦合系统的动力特性方程;并基于FSI系统的(ui,p)格式建立渡槽槽体-水体-槽墩-基础-地基系统的力学模型,采用非对称模态提取法求解了4种水深下渡槽的动力特性,并用隐式-显式积分算法计算了4种水深、2种强震作用下大型渡槽的动力响应.计算结果表明,基于FSI的(ui,p)格式,考虑到槽体与水体的相互作用,适应曲边FSI边界条件.简化了计算模型,提高了计算精度,同时也得出不同水深、不同激励下渡槽结构动力特性和动力响应的变化规律等结论,可为大型渡槽及同类工程抗震设计提供参考.

HEC-HMS模型在南水北调东线水资源调度中的应用

介绍了HEC-HMS水文模型系统,利用HEC-Geo HMS模块,由数字高程模型(DEM)生成洪泽湖、骆马湖、南四湖及东平湖上游数字流域,并对每个流域进行降雨径流模拟,模型考虑了流域内水利工程及河道取水的影响。结果表明:HEC-HMS模型应用方便,对南水北调东线沿线地区有较好的适用性,计算结果和观测入湖流量有较好的拟合,能为东线工程的水资源调度决策提供区间来水模拟预报。

基于TRMM数据的汉江流域1998年-2010年降水变化特征

汉江作为长江中游的最大支流和南水北调中线工程的水源地,其水资源补给主要靠流域降水,因此研究流域降水量的时空分布及其变化特性,对于流域水资源的合理开发与利用具有重要意思。论文采用1998年1月-2010年12月空间连续分布的TRMM卫星3B43月降水量资料,借助气候倾向率指数和GIS空间分析技术,对汉江流域近13年来的降水时空分布及其变化特征进行了定量化分析。从而为维系流域水资源供需平衡、生态环境可持续发展以及南水北调中线水量合理调配,提供基础数据和科学依据。