洋河水库富营养化评价及防治对策

在分析洋河水库富营养化发展及现状的基础上,采用营养状态指数法对其营养状况进行综合评价。评价结果表明,洋河水库富营养化日趋严重,已经由1990年的中营养发展到2004年的重度富营养。对富营养化成因进行分析,结果表明内源污染和外源污染是造成洋河水库富营养化的主要原因,其中淀粉废水和地表径流是主要的外污染源。最后根据分析结果提出洋河水库富营养化的防治对策。     

邯郸大型水库水体质量及富营养化综合评价

本文采用综合污染指数法和综合营养状态指数法对邯郸市两座大型水库进行了水体质量和富营养化评价。结果表明,两种方法的评价结果与实际水体状况相吻合,综合污染指数法能判断水体污染状况,综合营养状态指数法能判断水体的富营养化状态,且计算步骤简单,实用性较强,故两种方法相结合的评价方式更适合水库水环境评价。评价结果为邯郸市水资源科学管理、合理利用提供了科学依据。     

松花湖富营养化评价及防治措施

采用修正的卡森状态指数法进行松花湖水体富营养化评价,评价结果表明红石水库水质最好,白山水库次之,松花湖水质综合评价最差。由于辉发河带入的污染物较多,造成松花湖水质上游次于下游,越到下游水质越好,丰满水库的水质最优。全流域的富营养化指数为45.64,根据本研究选择的湖泊富营养状态分级标准,松花湖流域的富营养化总体处于中营养阶段,辉发河河口富营养程度最高,已达到轻度富营养化程度。     

基于灰色聚类分析的石岩水库富营养化评价

运用灰色聚类分析对水库富营养状况进行评估,旨在建立一种完善、合理的富营养化评价模型,为水库的管理提供依据。选用透明度(SD)、溶解氧(DO)、化学需氧量(COD)、总磷(TP)、总氮(TN)、氨氮(NH4-N)和叶绿素a(Chla)7个参数作为富营养化评价参数,将富营养化程度划分为贫营养、贫中营养、中营养、中富营养、富营养和极富营养6个等级,运用灰色聚类分析的方法对深圳石岩水库夏季富营养状况进行了评价。结果显示,石岩水库8个采样点均处于中富营养状态,但有着向富营养化演变的潜在风险;从水库的入水口至出水口,富营养化状态有轻微减轻趋势。灰色聚类分析方法应用于水库富营养化评价是可行的,评价结果客观、全面。     

基于浮游植物生物完整性指数的福建省水库健康状态评价

根据2021年夏季福建省24座重要饮用水水源地水库水生态调查结果,分析了浮游植物群落结构特征和水库营养状态,并采用浮游植物总密度、香农-维纳多样性指数和蓝藻门密度百分比3个生物参数构建浮游植物生物完整性指数(P-IBI)评价了沙溪口水库和东张水库的健康状态。结果表明:2021年福建省大部分水库的浮游植物群落结构以蓝藻-绿藻-硅藻为主,其中以蓝藻门为优势藻的水库占比为60.9%;综合营养状态指数范围为24.3~51.7,平均值为40.3,水库富营养化程度较低,但个别水库仍存在富营养化的风险;沙溪口水库P-IBI综合得分为79.7,处于健康状态,东张水库P-IBI综合得分为59.0,处于亚健康状态;P-IBI评价结果与《2021年福建省河湖健康评估蓝皮书》中的多指标评价方法的结果一致性较好,基于浮游植物生物完整性指数的评价方法具有有效性和适用性。     

卧龙湖富营养化程度随季节变化的研究

本文应用综合营养状态指数法评价卧龙湖水库富营养化程度随季节的变化。通过模糊数学综合评价指数法分析得出卧龙湖水质类别为Ⅴ类,与单指数法得出结论一致,证明模糊数学综合评价指数法可应用在卧龙湖水环境水质评价中。     

岸堤水库应对水质富营养化对策研究

采用综合营养状态指数法对岸堤水库富营养化程度进行综合评价,并对该水库水源地富营养化成因进行分析。结果表明,岸堤水库目前已经处于轻度富营养状态,在分析的基础上提出了遏制岸堤水库富营养化趋势的对策,以确保水资源的可持续利用。     

紫坪铺水库水环境质量现状及保护措施探析

紫坪铺水库的水质较好,大部分月份的水质达到Ⅱ类水质目标。各水质参数年内无明显变化规律,大部分水质指标都能满足Ⅱ类水质标准,其中总氮含量长期超标,铁含量在部分月份也处于超标状态。综合营养状态指数为29.09~45.7,以中营养状态为主。库区总氮含量较高,磷含量是藻类增长的限制因素,应作为水库富营养化防范的关键因子。特别应注意春季水库的富营养化,加强对坝前区域的监测。     

于桥水库富营养化评价及空间分布特征研究

基于天津市于桥水库2000-2010年水质数据,结合卡尔森富营养化指数与3种GIS空间插值方法(反距离权重、径向基函数、普通克里金),评价水库富营养化状态并对其空间分布特征及成因进行分析。结果表明:①普通克里金插值方法下的指数半方差模型插值精度较高。②水库富营养化主要表现为氮污染超标,有机污染较轻,磷为限制因子,在降雨集中的汛期(7-9月)水质营养状态空间差异显著。③水库整体水质呈中营养-轻富营养状态,范围为45.87~54.58,水库北岸由于沿岸畜禽养殖污染已处于轻富营养状态,南岸由于农业产生的面源污染呈现向富营养化转变的趋势,反映了水库富营养化空间分布状况,为建立有效的水库环境保护措施提供了新思路。     

江门市4宗大型水库富营养化评价与分析

应用特征法、参数法、营养状态指数法(TSI)和浮游植物生态学评价方法,对江门市4宗大型水库的富营养化水平进行评价.结果表明:锦江水库为贫-中营养型水库,大隆洞水库和大沙河为中-富营养型水库,但大沙河水库已接近富营养水平,镇海水库则是富营养型水库.     

Lakes of Malaysia: Water quality,eutrophication and management

The present study was undertaken to evaluate and verify the water quality status and trophic state of 15 major lakes and reservoirs in Malaysia. The lake water quality assessments were based on the National Water Quality Index (NWQI), while the trophic state assessments were based on Carlson's Trophic State Index (TSI). The findings of this water quality assessment, based on data collected between September and October 2012, indicated that a majority of the lakes were classified as Class II (Clean) waters suitable for recreational use. The results of the trophic state assessments, however, indicated that all of the lakes were eutrophic, meaning they were nutrient‐rich, they could experience algae blooms or macrophyte problems, and they were likely to exhibit poor water quality. Sustainable management measures and strategies are suggested to address the eutrophication problems of Malaysian lakes and reservoirs, with the national responses on lake and reservoir management also being discussed.     

Multi-Reservoir System Optimization using Chlorophyll-<Emphasis Type="Italic">a</Emphasis> Trophic Indexes

The problem of managing water scarcity by resorting to complex interconnected multi-source water systems needs to utilize management optimization techniques analyzing aspects of water quantity and quality in a common strategy. In the southern regions of Mediterranean Europe, the greater part of water resources for supply systems are derived from artificial reservoirs and water systems can become quite complex since they interconnect several sources and demand centers, as indeed occurs in the Region of Sardinia (Italy). A simplified approach to the requirement to insert water quality aspects in the mathematical optimization model can be achieved by examining the trophic conditions of reservoirs. Trophic State Indexes (TSI) based on Carlson’s (1977) make it possible to insert quality constraints in the water management optimization model also considering complex multi-reservoir and multi-user systems. Model formalization and implementation by the optimization toolkit WARGI (Water Resource system optimization aided by Graphical Interface) (Sechi and Zuddas 2000; Manca et al. 2004; Salis et al. 2005) is illustrated in this paper. The usefulness of a mixed quantity–quality optimization approach has been confirmed by WARGI application to a real multi-reservoir water resources system in southern Sardinia. The optimization model remains computationally efficient dealing with this complex multi-reservoir system and the obtained results can be seen as a reference target in a subsequent simulation phase.     

Empirical modeling of chlorophyll a from MODIS satellite imagery for trophic status monitoring of Lake Victoria in East Africa

We detail our attempts at empirical modeling of MODIS derived Chlorophyll a (Chl a) distribution on Lake Victoria in East Africa and consequently its trophic status. This was motivated by the need for Lake Victoria specific algorithms, as the current satellite based standard algorithms overestimate derived Chl a. In situ Chl a data was hence collected in three field campaigns in November 2014, March 2015 and July 2015. In situ reflectances were collected during the July campaign only. We first developed models from in situ reflectances and in situ Chl a, which when applied to MODIS bands performed dismally (R² = 0.03). We then proceeded to derive empirical models by directly comparing MODIS bands with in situ Chl a based on data collected in November 2014 and July 2015. The March 2015 dataset couldn’t be used due to cloud cover hence no matchups could be obtained. The best model derived (R² = 0.88) was based on the ratio 488 nm/645 nm, and was then used to determine the trophic status of Lake Victoria using Carlson’s Chl a Trophic State Index (TSI). The results show that large areas of the lake are mesotrophic with eutrophic displays closer to the shores. The modeled TSI was then validated against in situ TSI derived from the March dataset and posted an 80% matchup. One of the main challenges, however is the prevalence of cloud cover, which hinders synoptic mapping of the lake. That notwithstanding, the study demonstrates the potential of earth observation in providing accurate TSI information for improved management of Lake Victoria.     

洋河水库富营养化限制性因子分析

以洋河水库2001~2005年的监测资料为基础,运用回归统计方法,选择水温等8项环境理化指标与藻类叶绿素a进行回归分析。结果显示,总磷、水温、pH值和透明度与藻类叶绿素a呈显著相关,其中总磷和水温是洋河水库富营养化限制性因子。根据2003~2005年水库监测资料,建立多元逐步回归方程,预测水库藻类叶绿素a的变化情况。运用该回归方程,计算水库2001~2002年藻类叶绿素a变化情况并与实测值作比较,结果表明,该方程能基本预测洋河水库藻类叶绿素a的变化趋势。     

天津滨海新区水库水质状况分析

通过现场采样与室内分析,获取了滨海新区水库水质数据,采用综合指数法对滨海新区各水库富营养化进行了评价。结果显示,滨海新区营城水库出现了轻度富营养,其余各水库均为中营养;沙井子水库、营城水库、钱圈水库的个别指标超过《地表水环境质量标准》(GB 3838-2002)IV类水质标准,北大港水库及北塘水库超过地表水III类水质标准;作为未来天津水源地之一的北大港水库的总磷、总氮、化学需氧量等指标均超过饮用水水质标准,因此急需采取必要的水质净化措施。     

苏家屯地区地下水源地水质调查与聚类分析

本文通过实际调查取样测定分析了苏家屯地区20个饮用水水质点相关水质参数,在此基础上运用营养状态指数法(Trophic State Index)对区域水质季候特征进行综合评定。并采用主成分分析法解析水质影响因素,通过自组织神经网络(Self-Orhainzing Map SOM)对各水体质量进行聚类。结果表明该区域水质季节性差异显著(P<0.05),其优劣程度综合排序为秋、春、冬、夏,但均符合安全饮用标准。区域水质受pH值、TN、TP等理化性质影响较大,是水质安全的控制因素。SOM聚类分析表明,区域水质点综合质量存在差异。     

白洋淀水环境质量评价

由于流域人类活动和气候干旱化的影响,白洋淀水体污染与富营养化日趋严重。通过对白洋淀湖水化学成分的分析,并运用与湖泊富营养化关系最为密切的Chla、TN、TP、CODMn和SD作为评价参数,采用综合营养指数法确定湖水营养类型。湖水水质监测数据分析表明,白洋淀为重碳酸类钠组Ⅱ型水的偏碱性湖泊,综合营养指数法确定湖水为中-富营养级湖泊水体。主成分分析法结果显示,湖泊污染的主要因子是TP。借助硅藻及其组合分析了湖泊富营养化状况,发现白洋淀硅藻属种以耐营养种梅尼小环藻Cyclotellameneghiniana(20.43%)和Cyclostephanos tholiformis(25.40%)为组合特征,表明湖泊水体已处于富营养化状态,水环境状况堪忧。     

Unraveling the Lagged Effect of Hydro-meteorological Conditions On the Trophic State of a Reservoir By Applying Dynamic Regression

In this study we develop a novel approach to quantify the relative importance of hydro-meteorological (HM) conditions on the trophic state index (TSI) of a water reservoir (San Roque, Córdoba, Argentina). Seven HM variables measured at four reservoir sites and different depths over a time period of near 2 decades are used. We propose a dynamic regression model to predict the TSI from these variables aggregated over a range of time lags, which has not been applied in such a complex setting so far. By performing coefficient analysis, we quantify the relative importance of these variables on the TSI, as well as the time duration over which they have significant impact (lagged effect). Additionally, the analysis of the autoregressive and moving average (ARIMA) terms reveals the impact of the residual effects of previous trophic states on the current trophic state. We find that surface temperature and precipitation have the largest direct relationship to the TSI in the short-term, while the reservoir water level is inversely related to the TSI in the short- to mid-term. Also, the residual effects of the trophic state impact from 1 month (generally) up to 2 years (exceptionally). This approach can be applied to other water bodies affected by similar eutrophication phenomena.

Graphical abstract

     

Nutrient reference concentrations and trophic state boundaries in subtropical reservoirs

Nutrient criteria as reference concentrations and trophic state boundaries are necessary for water management worldwide because anthropogenic eutrophication is a threat to the water uses. We compiled data on total phosphorus (TP), nitrogen (TN) and chlorophyll a (Chl a) from 17 subtropical reservoirs monitored from 2005-2009 in the S?o Paulo State (Brazil) to calculate reference concentrations through the trisection method (United States Environmental Protection Agency). By dividing our dataset into thirds we presented trophic state boundaries and frequency curves for the nutrient levels in water bodies with different enrichment conditions. TP and TN baseline concentrations (0.010 mg/L and 0.350 mg/L, respectively) were bracketed by ranges for temperate reservoirs available in the literature. We propose trophic state boundaries (upper limits for the oligotrophic category: 0.010 mg TP/L, 0.460 mg TN/L and 1.7 μg Chl a/L; for the mesotrophic: 0.030 mg TP/L, 0.820 mg TN/L and 9.0 μg Chl a/L). Through an example with a different dataset (from the Itupararanga Reservoir, Brazil), we encouraged the use of frequency curves to compare data from individual monitoring efforts with the expected concentrations in oligotrophic, mesotrophic and eutrophic regional systems. Such analysis might help designing recovery programs to reach targeted concentrations and mitigate the undesirable eutrophication symptoms in subtropical freshwaters.