ANALYSIS OF DATA FROM BIOLOGICAL SURVEYS OF STREAMS: DIVERSITY AND SAMPLE SIZE1

ABSTRACT: Brillouin's equation (H) for species diversity from information theory is to be preferred for the purposes of applied ecology over the equation of Shannon (H′) or the more commonly used approximate equation (H″). By its use, the difficult problem of delimiting the extent of the community being sampled in a stream survey can be avoided. Moreover, Brillouin's equation gives the exact diversity of the fully censused collection, whreas Shannon's diversity can only be approximated with a biased estimator. If we regard a sample as a message from the environment to the ecologist, Brillouin's equation is the proper one for computing its diversity. The product moment correlation coefficient between Brillouin's H for the total number of individuals from a group of samples and for randomly chosen subsets of 100 individuals from each sample was nearly as high as the correlation between H and H″ based on the total samples. This indicates that small sample sizes may give a useful diversity index. Replicated subsamples show that much smaller samples than are normally used can discriminate between communities from polluted and unpolluted environments. The use of smaller samples should reduce the cost of stream surveys.     

ACUTE RESIDUAL TOXICITY OF SEVERAL WASTEWATER DISINFECTANTS TO AQUATIC LIFE1

ABSTRACT: This study was conducted to determine the comparative acute toxicity of chlorine, bromine chloride and ozone in wastewater, and to determine any acute toxicity associated with chlorinated wastewater which had been dechlorinated with sulfur dioxide. Toxicity tests were conducted with several species of cyprinids, salmonids and centrarchids, and the freshwater macroinvertebrate, Daphnia magna. Chlorinated effluent exhibited the greatest potential for residual toxicity of any disinfected stream tested. The reduced residual toxicity of chlorobrominated or ozonated effluent was largely the result of the more rapid dissipation of these disinfectants in wastewater. The acute residual toxicity of chlorinated effluent was eliminated by dechlorination with sulfur dioxide.     

水质转化的现代科学与技术：兼谈环境水化学实验室的科研方向

本文综述了当前环境水化学的发展趋势及其中苦干部分的研究动态与方向，例如：化学形态分布、酸化与风化、表面络合、沉积物质量评价、生态毒理、水陆交错带、水处理中的絮凝、膜分离、化学氧化、生物氧化和水质模式。离作者的若干观点及对环境水化学实验室近期研究方向的一些看法。     

The Institute of Hydrobiology of the Chinese Academy of Sciences (1 p.)

- The Institute of Hydrobiology (IHB), Chinese Academy of Sciences (CAS) is located at the foot of Luojia Hill and beside the beautiful Donghu Lake in the City of Wuhan, Hubei Province, China. It was founded in 1930 as the Natural History Museum of Academia Sinica, and renamed as the Institute of Zoology and Botany of Academia Sinica in 1934. In 1944, it was divided into two institutes: The Institute of Zoology and Institute of Botany. In 1950, the main part of the Institute of Zoology, the sections of phycology in the Institute of Botany, and some members from other institutes and universities were merged into the Institute of Hydrobiology of the Chinese Academy of Sciences in Shanghai. The institute was moved from Shanghai to Wuhan in 1954.     

植物对水溶液中乐果的降解及影响因素分析

通过气相色谱分析,建立浓度换算标准曲线,研究了三种水生植物水葱、香蒲和石菖蒲对水溶液中乐果的降解效果,并进一步探讨了水葱对乐果降解的动力学过程和各因素对乐果去除的贡献。结果表明,三种植物对乐果去除能力由大到小依次为:水葱,香蒲,石菖蒲。水葱10天内对乐果的去除率为58%,香蒲和石菖蒲组对乐果的去除率分别为39%和33%。乐果的自然降解和挥发、植物吸收和微生物降解作用对乐果去除的贡献率约为:20%、40%、30%。水体的pH升高能够加速乐果的降解,营养盐质量浓度的下降不利于植物去除乐果。     

环境雌激素对水生动物的影响研究进展

水环境是环境雌激素的最大储存库。环境雌激素通过食物的传递进入动物体内，类似于雌激素的功能。环境雌激素可导致水生动物性别特征丧失和后代不能繁殖；可引起水蚤性别比例失调，蜕皮率下降，导致软体动物性畸形和超雌性化现象；导致鲤鱼等生殖器畸形，引起鱼类种群生存力和资源量下降。壬酚(NP)、双酚A(BPA)和E2在河水、水生附着生物和底栖生物之间的生物积累与放大倍数在18～1200倍之间，环境激素通过食物链的生物放大作用比通过水体的传递对鱼类等水生生物的危害更大，并且在河流等的枯水期对水生动物的影响更大。文章讨论了环境雌激素的降解与研究前景。     

水中天然有机物的臭氧氧化处理特性

通过小型实验和液相色谱分析，研究了水中天然有机物的臭氧氧化反应的特性和反应前后有机物分子量的变化情况。结果表明，臭氧氧化的主要功效不在于降低以TOC为代表的水中有机物总量，而是改变了有机物的性质和结构。通过臭氧氧化处理，水中大分子有机物分解氧化为小分子有机物分解氧化为小分子有机物，且具有饱和构造的有机物成分明显增加。     

A Probabilistic Screening Model for Evaluating Pyrethroid Surface Water Monitoring Data

Synthetic pyrethroids have been detected in recent California surface water monitoring. Filtration is avoided during sample workup because pyrethroids are extremely hydrophobic, tending to sorb to most surfaces. The resultant analytical pyrethroid concentrations reflect both dissolved pyrethroid and pyrethroid associated with suspended sediment in the water column. Such “whole-water” analytical data are not directly comparable to aquatic acute toxicity effect concentrations measured in laboratory sediment-free water. Consequently, any potential aquatic toxicity risk is indeterminate. In this study a simple probabilistic model was developed to allow a screening-level assessment of pyrethroid whole-water monitoring data. The results suggest that water column toxicity of pyrethroids is possible in California's agriculturally-dominated tributaries, and indicate that additional monitoring to better characterize pyrethroid water-column concentrations are warranted. Model refinement will depend on future work that more firmly establishes the relationship between pyrethroid partitioning and bioavailability, and that addresses the potential influence of dissolved organic carbon on pyrethroid sorption and bioavailability.     

Monitoring Long-Term Ecological Changes Through the Ecological Monitoring and Assessment Network: Science-Based and Policy Relevant

Ecological monitoring and its associated research programshave often provided answers to various environmental management issues. In the face of changing environmental conditions, ecological monitoring provides decision-makers with reliable information as they grapple with maintaining a sustainable economy and healthy environment. The EcologicalMonitoring and Assessment Network (EMAN) is a national ecological monitoring network consisting of (1) about 100 casestudy sites across the country characterized by long-term multi-disciplinary environmental work conducted by a multitudeof agencies (142 partners and counting); (2) a variety of lesscomprehensive yet more extensive monitoring sites; (3) a network where core monitoring variables of ecosystem change aremeasured; and (4) geo-referenced environmental observations. Environment Canada is the co-ordinating partner for the network through the EMAN Co-ordinating Office. EMAN's mission is to focus a scientifically-sound, policy-relevant ecosystem monitoring and research network based on (a) stabilizing a network of case-study sites operated by a varietyof partners, and (b) developing a number of cooperative dispersedmonitoring initiatives in order to deliver unique and needed goods and services. These goods and services include: (1) an efficient and cost-effective early warning system which detects,describes and reports on changes in Canadian ecosystems at a national or ecozone scale; and (2) cross-disciplinary and cross-jurisdictional assessments of ecosystem status, trends and processes. The early warning system and assessments of ecosystem status, trends and processes provide Environment Canada and partner organizations with timely information thatfacilitates increasingly adaptive policies and priority setting. Canadians are also informed of changes and trends occurring in Canadian ecosystems and, as a result, are betterable to make decisions related to conservation and sustainability.     

应用生物完整性指数评价我国河流的生态健康

河流生态健康评价是开展流域水生态健康评估和管理的重要技术基础,生物完整性是评估流域生态完整性的重要构成指标.基于生物群落特征参数的多参数指数（MMI）和预测模型的样点物种组成观测值与期望值比值的O/E指数（O,观测值;E,期望值）,是应用最广泛的评价生物完整性的两个重要指数;美国和欧盟等都已建立完善的基于生物完整性指数评价水生态健康的国家和地方规范.本文综述了MMI和O/E指数的基本概念和构建方法,比较了两者的共同点和优缺点;回顾了两者的发展简史和国内外的应用现状,分析了目前我国对MMI和O/E指数研究与应用的现状和不足,并提出了国内未来研究和应用MMI与O/E指数的建议.