贵州高原水库浮游生物群落稳定性及其环境驱动因子辨识

为了解贵州高原水库环境下,浮游动物及浮游植物群落稳定性情况,水库水质变化影响浮游生物稳定性的过程. 于2020年10月和2021年的4、6、8月对3座不同营养型水库（花溪水库、构皮滩水库和海龙水库）的浮游生物群落变化及水质变化进行研究,结合时滞分析（TLA）研究浮游动物和浮游植物群落稳定性,使用方差分解分析（VPA）探究两个群落对环境变化的响应,揭示水库浮游生物群落变化的驱动因子. 结果表明,3座水库的综合营养指数（TLI）均值为44.07、44.68和50.25. 花溪水库和构皮滩水库为中营养型水库,海龙水库为富营养型水库. 总共鉴定出浮游动物轮虫51种,轮虫39种,桡足类3种和枝角类9种. 其中轮虫丰度最多,占85.96%. 浮游植物鉴定出7门73种,蓝藻门16种,绿藻门32种,硅藻门16种,甲藻门3种,裸藻门4种,隐藻和金藻门各1种. 其中蓝藻门和硅藻门丰度占比最大,分别为66.2%和27.35%. 浮游动物和浮游植物群落Bray-Curtis距离的绝对偏差中位数（MAD）分别为：花溪水库0.67和0.65、构皮滩水库0.80和0.69、海龙水库0.85和0.47,值越大说明群落的变异越大. TLA结果中浮游动物的斜率绝对值大于浮游植物的绝对值,斜率绝对值分别为0.018和0.004,斜率绝对值越大群落变异速度越快. 浮游动物群落相对浮游植物群落稳定性更低,对环境变化的响应更敏感,变异程度更大. 水库的富营养状态程度越高,这种现象越明显. VPA显示,花溪水库和海龙水库浮游生物群落变化主要受到水温和富营养化因子影响. 构皮滩水库浮游生物群落变化主要受到水温和化学因子的影响. 花溪水库的驱动因子为水温、TP、高锰酸盐指数和SD. 构皮滩水库驱动因子为水温、NO₃^--N和pH. 海龙水库的驱动因子为水温和TP. 水温和营养盐是影响水库浮游生物群落稳定性的主要原因.     

粤北2座不同营养水平水库浮游植物功能类群的季节演替

于2011年1—12月对广东省韶关市白水礤水库和苍村水库这2座中型居民供水水库进行每月1次、为期1a的采样,利用营养状态指数(TSI)进行水质综合评价,将水库中的浮游植物按功能类群进行分类,并结合水库的水文、水质和浮游植物的生境特征,分析全年优势功能类群的演替特点及其主要的环境影响因子。结果表明,白水礤水库为贫营养型水库,苍村水库为低中营养型水库,全年共检出浮游植物7门45属(种),可划分为16个功能类群,其中,白水礤水库全年以适应低营养盐环境的功能类群占优势,耐富营养化的功能类群仅在丰水期有检出;而苍村水库全年都能监测到耐富营养环境的功能类群,且在丰水期明显占优势,但在枯水期和平水期因营养盐含量的降低,演变为以适应低营养盐环境的功能类群为主。营养盐含量的不同是导致2座水库浮游植物功能类群产生差异的根本原因,而因降水季节的变化所致水体环境因子的变化则是造成2座水库浮游植物功能类群演替不可忽视的因素。     

白龟山水库规划区污染特征及潜在生态风险评价

分析了白龟山水库及其入库河流水体和沉积物中TN,TP,有机质和Cd,Pb,Cr,Cu,Zn,Mn,Ni等7种重金属的含量及分布特征,并结合地积累指数法和HANKANSON生态危害指数法对沉积物重金属的累积效应和潜在生态风险进行评价. 结果表明:白龟山水库规划区内水库及河流水体主要污染物为TN和TP,其中鲁山污水厂出口断面严重超标,ρ(TN)和ρ(TP)高达《国家地表水环境质量标准》(GB3838—2002)Ⅱ类水质标准的46.4和22.1倍;w(TN),w(TP),w(Cd),w(Pb),w(Cr),w(Cu),w(Zn)与w(OM)呈显著正相关,而w(Mn)和w(Ni)与w(OM)的相关性不显著;鲁山污水厂出口沉积物重金属的生态危害最大,RI为241.13,为中等生态危害,以Cd和Cu的生态危害为主,特别是Cd作为最主要的生态风险贡献因子,应适当引起重视.      

三峡库区主要粮食作物和土壤中重金属的相关性及富积特征分析

采用野外采样和室内分析,试验结果表明三峡库区土壤中重金属Cu、Zn、Pb、Cd、Fe、Cr的变异系数小于50%,重金属的含量比较稳定。稻谷（Oryza sativa）中Cu、Zn、Pb、Cd、Fe、Mn、Cr,玉米（Zea mays）中Pb、Cd、Fe、Mn、Cr和小麦（Triticum aestivum）中Cu、Pb、Cd、Fe、Mn、Cr的变异系数大于50%。土壤、稻谷、玉米、小麦中大部分重金属呈偏态分布。土壤中重金属间均为正相关,且极显著正相关性明显。稻谷、玉米、小麦中重金属间有正相关,也有负相关,但正相关明显多于负相关;稻谷、玉米、小麦中Mn同其它重金属间均有显著正相关性,协同作用明显。稻谷、玉米、小麦中Pb、Cd、Cr的样本超标率较大,污染明显,并且稻谷中Cd与土壤中Cd有直线关系。     

SEASONAL ARIMA INFLOW MODELS FOR RESERVOIR SIZING1

ABSTRACT: The reliable sizing of reservoirs is a very important task of hydraulic engineering. Although many reservoirs throughout the world have been designed using Rippl's mass curves with historical inflow volumes at the dam site, this technique is now considered outdated. In this paper, synthetic series of monthly inflows are used as an alternative to historical inflow records. These synthetic series are generated from stochastic SARIMA (Seasonal Autoregressive Integrated Moving Average) models. The analyzed data refer to the planned Almopeos Reservoir on the Almopeos River in Northern Greece with 19‐year monthly inflow series. The analysis of this study demonstrates the ability of SARIMA models, in conjunction with the adequate transformation, to forecast monthly inflows of one or more months ahead and generate synthetic series of monthly inflows that preserve the key statistics of the historical monthly inflows and their persistence Hurst coefficient K. The forecasted monthly inflows would be of help in evaluating the optimal real time reservoir operation policies and the generated synthetic series of monthly inflows can be used to provide a probabilistic framework for reservoir design and to cope with the situation where the design horizon of interest exceeds the length of the historical inflow record.     

RIVERWARE: A GENERALIZED TOOL FOR COMPLEX RESERVOIR SYSTEM MODELING1

ABSTRACT: Water management agencies seek the next generation of modeling tools for planning and operating river basins. Previous site‐specific models such as U.S. Bureau of Reclamation's (USBR) Colorado River Simulation System and Tennessee Valley Authority's (TVA) Daily Scheduling Model have become obsolete; however, new models are difficult and expensive to develop and maintain. Previous generalized river basin modeling tools are limited in their ability to represent diverse physical system and operating policy details for a wide range of applications. RiverWare(tm), a new generalized river basin modeling tool, provides a construction kit for developing and running detailed, site‐specific models without the need to develop or maintain the supporting software within the water management agency. It includes an extensible library of modeling algorithms, several solvers, and a rich “language” for the expression of operating policy. Its point‐and‐click graphical interface facilitates model construction and execution, and communication of policies, assumptions and results to others. Applications developed and used by the TVA and the USBR demonstrate that a wide range of operational and planning problems on widely varying basins can be solved using this tool.     

OPTIMAL CONTROL OF RESERVOIR RELEASES TO MINIMIZE SEDIMENTATION IN RIVERS AND RESERVOIRS1

ABSTRACT: An optimal control methodology and computational model are developed to evaluate multi‐reservoir release schedules that minimize sediment scour and deposition in rivers and reservoirs. The sedimentation problem is formulated within a discrete‐time optimal control framework in which reservoir releases represent control variables and reservoir bed elevations, storage levels, and river bed elevations represent state variables. Constraints imposed on reservoir storage levels and releases are accommodated using a penalty function method. The optimal control model consists of two interfaced components: a one‐dimensional finite‐difference simulation module used to evaluate flow hydraulics and sediment transport dynamics, and a successive approximation linear quadratic regulator (SALQR) optimization algorithm used to update reservoir release policies and solve the augmented control problem. Hypothetical two‐reservoir and five‐reservoir networks are used to demonstrate the methodology and its capabilities, which is a vital phase towards the development of a more robust optimal control model and application to an existing multiple‐reservoir river network.     

水源水库沉积物及其上覆水DOM光谱特征

为探究水源水库溶解性有机质(DOM)组成结构及来源,以深圳市茜坑水库为例,采用紫外-可见光谱技术(UV-Vis)并结合平行因子分析法三维荧光光谱技术(EEMs-PARAFAC)对水库表层沉积物及其上覆水的DOM光谱特征进行分析.结果表明:PARAFAC识别出3类荧光组分,分别是Cl(Ex/Em=270/304nm,类蛋...     

不同除险加固方案下病险水库渗流特性研究

为了给病险水库制定更加合理有效的除险加固方案.以某病险水库为研究对象,采用SEEP/W进行数值模拟,得出渗流量、出逸坡降、出逸流速、防渗墙底部渗透坡降,研究不同除险加固方案下水库的渗流特性.研究结果表明:未除险加固时,大坝渗流量、出逸坡降、出逸流速随着水位升高而增大;3种除险加固方案下,大坝渗流量、出逸坡降、出逸流速皆...     

强化混凝-氧化处理含溴氰菊酯农药水库水

通过投加不同混凝剂、助凝剂和氧化剂,对含溴氰菊酯农药的某水库原水进行强化混凝-氧化处理,探讨了不同条件下对原水的处理效果.结果表明,当对水样仅作常规混凝处理时,聚合氯化铝(PAC)的处理效果优于其他混凝剂,最佳投加量为18mg/L,最佳pH为9,最高去除率可达64.5％.投加助凝剂可提高混凝效果,聚丙烯酰胺(PAM)助凝效果优于水玻璃.混凝后水样再用高锰酸钾(KMnO4)氧化处理,结果表明,在水样pH为5,KMnO4投加量为0.6mg/L,氧化时间为25 min的条件下,溴氰菊酯去除率最高可达82.4％.