水生生物学在生态环境保护中的应用研究进展

水生生物学不但与生态学、湖沼学、海洋科学、渔业等密切相关,而且已经在环境监测和污水处理等方面得到了很多应用。本文针对如何将水生生物学应用到水环境监测中以及水生生物在水环境保护中能够起到的作用与研究进展进行了分析及阐述。     

Concentrations of heavy metals and aquatic macrophytes of Govind Ballabh Pant Sagar an anthropogenic lake affected by coal mining effluent

Five heavy metals Cu, Cd, Mn, Pb and Hg were found in high concentration from three sampling sites located in Asia’s largest anthropogenic lake Govind Ballabh Pant GBP Sagar. Concentrations of these heavy metals were measured in Water, bottom sediment and in different parts of the aquatic macrophytes collected from the reservoir. Plants collected from the lake were Eichhornia crassipes, Azolla pinnata, Lemna minor, Spirodela polyrrhiza, Potamogeton pectinatus, Marsilea quadrifolia, Pistia stratiotes, Ipomea aquqtica, Potamogeton crispus, Hydrilla verticillata and Aponogeton natans. These plants have shown the high concentrations of Cu, Cd, Mn, Pb and Hg in their different parts due to bioaccumulation. In general plant roots exhibited higher concentrations of heavy metals than corresponding sediments. A comparison between different morphological tissues of the sampled plants reveled the metal concentration in following order roots > leaves. Analyses of bottom sediment indicated the higher concentrations of Cd, Mn, Cu and Pb. Strong positive correlations were obtained between the metals in water and in plants as well as between metal in sediment and in plants. Indicating the potential of these plants for pollution monitoring of these metals.     

Accumulation of Am by suspended matter, diatoms and aquatic weeds of the Yenisei River

In this work we experimentally estimated the capacities of the key components of the Yenisei River (Russia): particulate suspended matter (seston), diatom microalgae, and submerged macrophytes for accumulating ²⁴¹Am from water. In our experiments large particles of seston (>8 μm), comparable in size with diatoms, took up most of americium from water. The accumulation of americium by isolated diatom algae (Asterionella formosa and Diatoma vulgare) was lower than by total seston. The concentration factors (CFs) of ²⁴¹Am for seston of the Yenisei River in our experiments were (2.8-6.9)·10⁵; for diatoms - (1.5-4.2)·10⁴. The CFs for aquatic plant Elodea canadensis were within the same order of magnitude as those for diatoms. Activity concentration and CFs of ²⁴¹Am were nearly the same in experiments under dark and light conditions. This is indicative of an energy independent mechanism of americium uptake from the water by diatoms and submerged macrophytes.     

Selenium concentrations in water and plant tissues of a newly formed arid wetland in Las Vegas, Nevada

There is concern that elevated levels of selenium found in the source water of a newly formed wetland park in Las Vegas, Nevada, may have detrimental effects on local wildlife. In this study, we collected and analyzed water samples monthly for a three year period from the inflow and outflow of the system. We also gathered dominant aquatic plants and selected terrestrial plants and analyzed the water and plant tissues (root, shoot, leaf and flower) for selenium by high resolution Inductively Coupled Plasma Mass Spectrometer. Except for storm events and the introduction of an alternative low selenium content source water during summer low-flow conditions, selenium in the water was relatively stable. The concentration in the outflow tended to be slightly lower than the inflow. Concentrations of selenium in the dominant plant taxa in this wetlands were typical of ecosystems in the western United States and varied by taxa, tissue type, localized conditions (e.g., contact with selenium-laden water), and to a lesser extent, seasons. Selenium in the aquatic plant spiny naiad (Najas marina) was relatively high and may pose an ecological risk to wildlife during the late spring and summer. Additional work is underway investigating aquatic food chain accumulations of selenium as well as mass balance of selenium in the system.     

高等水生植物体内酶活性与污水净化

通过研究几种常见高等水生植物净化污水的效果，对水生植物的生理活性与水质的净化关系进行了初步探讨．酶活性的研究结果表明，植物体内过氧化物酶活性的提高，有助于促进植物体的生理代谢活动，并加速水中污染物质的去除速率．植物体内酶活性与水中某些污染物质的去除间呈一定的线性关系．     

水环境质量评价标准探讨

水环境质量评价指标是开展评价工作的依据，本文针对地表水体质量标准、底泥质量标准和水生生物质量标准及共统一结合问题进行了探讨，为全面开展水环境质量评价提供更科学的决策依据。     

临江河水生生物体中重金属含量的模糊评价

水体的环境变化直接影响着水生生物的质量,重金属在水生生物中的富集含量,在很大程度上说明水生生物受污染的状况。本文主要研究评价了临江河水生生物中重金属的状况,为该河水生生物资源的开发利用提供科学依据。      

大型水生植物对东太湖河湖交汇区矿质元素分布特征的影响

河流是湖泊物质运移的重要通道,对湖泊生态系统有重要的影响.各矿质元素及营养物质迁移、累积使得河湖交汇处成为重金属元素和营养物质的汇库.通过对太湖的入湖河流及其与太湖交汇区域不同植物群落沉积物中矿质元素、有机质含量分析.结果表明:河流表层沉积物重金属元素含量是其与太湖交汇区表层沉积物重金属元素含量的4～5倍.而元素间的相关系数因不同的生态环境存在差异,且P、Ca、Cu、Sr与其它元素间在河湖交汇区及定向河道均无显著相关关系;而SOM在河湖交汇区有强相关,而在河流中则否.     

A Bayesian hierarchical framework for calibrating aquatic biogeochemical models

Model practitioners increasingly place emphasis on rigorous quantitative error analysis in aquatic biogeochemical models and the existing initiatives range from the development of alternative metrics for goodness of fit, to data assimilation into operational models, to parameter estimation techniques. However, the treatment of error in many of these efforts is arguably selective and/or ad hoc. A Bayesian hierarchical framework enables the development of robust probabilistic analysis of error and uncertainty in model predictions by explicitly accommodating measurement error, parameter uncertainty, and model structure imperfection. This paper presents a Bayesian hierarchical formulation for simultaneously calibrating aquatic biogeochemical models at multiple systems (or sites of the same system) with differences in their trophic conditions, prior precisions of model parameters, available information, measurement error or inter-annual variability. Our statistical formulation also explicitly considers the uncertainty in model inputs (model parameters, initial conditions), the analytical/sampling error associated with the field data, and the discrepancy between model structure and the natural system dynamics (e.g., missing key ecological processes, erroneous formulations, misspecified forcing functions). The comparison between observations and posterior predictive monthly distributions indicates that the plankton models calibrated under the Bayesian hierarchical scheme provided accurate system representations for all the scenarios examined. Our results also suggest that the Bayesian hierarchical approach allows overcoming problems of insufficient local data by “borrowing strength” from well-studied sites and this feature will be highly relevant to conservation practices of regions with a high number of freshwater resources for which complete data could never be practically collected. Finally, we discuss the prospect of extending this framework to spatially explicit biogeochemical models (e.g., more effectively connect inshore with offshore areas) along with the benefits for environmental management, such as the optimization of the sampling design of monitoring programs and the alignment with the policy practice of adaptive management.     

利用水生植物改善北京动物园水环境的研究初探

近年来，北京动物园的水体出现严重的富营养化问题，为了净化水环境，本课题采用了水生植物净化水体的生态工程方法进行了研究。研究结果表明，利用水生植物不仅能净化北京动物园水体，而且还有利于营造水上园林景观和水禽创造适宜的生存环境。从单一水生植物的净化作用上看，水葫芦的净化效果最好，次之为睡莲和野生荷花。人工种植的荷上对较差；多种水生植物的组合更有利于植物在净化作用上的优势互补，从而能始终保持较好的净化效果。此外，试验还发现香蒲的适生水深为0.3-0.4m。