北京市北沙河上游典型小流域水环境治理措施的生态效益分析

北京市属于资源型重度缺水地区,水资源紧缺严重制约其可持续发展,加之水质恶化,造成了全市水资源和水环境形势严峻的局面.为此,北京市布设相应措施对小流域水环境问题进行治理,分析治理措施的生态效益能够为小流域水环境治理措施的合理布设提供科学依据.以北京市昌平区北沙河上游8条小流域为研究区,基于In VEST(Integrat...     

Determination of trichloroacetic acid in environmental studies using carbon 14 and chlorine 36

Radioisotopes carbon 14 and chlorine 36 were used to elucidate the environmental role of trichloroacetic acid (TCA) formerly taken to be a herbicide and a secondary air pollutant with phytotoxic effects. However, use of ¹⁴C-labeling posed again known analytical problems, especially in TCA extraction from the sample matrix. Therefore—after evaluation of available methods—a new procedure using decarboxylation of [1,2-¹⁴C]TCA combined with extraction of the resultant ¹⁴C-chloroform with a non-polar solvent and its subsequent radiometric measurement was developed. The method solves previous difficulties and permits an easy determination of amounts between 0.4 and 20 kBq (10–500 ng g⁻¹) of carrier-less [1,2-¹⁴C]TCA in samples from environmental investigations. The procedure is, however, not suitable for direct [³⁶Cl]TCA determination in chlorination studies with ³⁶Cl. Because TCA might be microbially degraded in soil during extraction and sample storage and its extraction from soil or needles is never complete, the decarboxylation method—i.e. 2 h TCA decomposition to chloroform and CO₂ in aqueous solution or suspension in closed vial at 90 °C and pH 4.6 with subsequent CHCl₃ extraction—is recommended here, estimated V < 7%. Moreover, the influence of pH and temperature on the decarboxylation of TCA in aqueous solution was studied in a broad range and its environmental relevance is shown in the case of TCA decarboxylation in spruce needles which takes place also at ambient temperatures and might amount more than 10–20% after a growing season. A study of TCA distribution in spruce needles after below-ground uptake shows the highest uptake rate into current needles which have, however, a lower TCA content than older needle-year classes, TCA biodegradation in forest soil leads predominatingly to CO₂.     

Scientific research, stakeholders, and policy: continuing dialogue during research on radionuclides on Amchitka Island, Alaska

It is increasingly clear that a wide range of stakeholders should be included in the problem formulation phase of research aimed at solving environmental problems; indeed the inclusion of stakeholders at this stage has been formalized as an integral part of ecological risk assessment. In this paper, we advocate the additional inclusion of stakeholders in the refinement of research methods and protocols and in the execution of the research, rather than just at the final communication and reporting phase. We use a large study of potential radionuclide levels in marine biota around Amchitka Island as a case study. Amchitka Island, in the Aleutian Island Chain of Alaska, was the site of three underground nuclear tests (1965-1971). The overall objective of the biological component of the study was to collect a range of marine biota for radionuclide analysis that could provide data for assessing current food safety and provide a baseline for developing a plan to monitor human and ecosystem health in perpetuity. Stakeholders, including regulators (State of Alaska), resource trustees (US Fish and Wildlife Service, State of Alaska), representatives of the Aleut and Pribilof Island communities, the Department of Energy (DOE), and others, were essential for plan development. While these stakeholders were included in the initial problem formulation and approved science plan, we also included them in the refinement of protocols, selection of bioindicators, selection of a reference site, choice of methods of collection, and in the execution of the study itself. Meetings with stakeholders resulted in adding (or deleting) bioindicator species and tissues, prioritizing target species, refining sampling methods, and recruiting collection personnel. Some species were added because they were important subsistence foods for the Aleuts, and others were added because they were ecological equivalents to replace species deleted because of low population numbers. Two major refinements that changed the research thrust were (1) the inclusion of Aleut hunters and fishers on the biological expedition itself to ensure that subsistence foods and methods were represented, and (2) the addition of a fisheries biologist on a NOAA research trawler to allow sampling of commercial fishes. Although the original research design called for the collection of biota by Aleut subsistence fishermen, and by a commercial fishing boat, the research was modified with continued stakeholder input to actually include Aleuts and a fisheries biologist on the expeditions to ensure their representation. The inclusion of stakeholders during the development of protocols and the research itself improved the overall quality of the investigation, while making it more relevant to the interested and affected parties. Final responsibility for the design and execution of the research and radionuclide analysis rested with the researchers, but the process of stakeholder inclusion made the research more valuable as a source of credible information and for public policy decisions.     

Multi-scales Analysis of Driving Forces on Land Use/Cover Change in China： Taking Farmland Returning to Forest or Grassland as a Case

Increasing populations are causing an increase in food demands, and the area of cultivated land expands every year. Inappropriate land transition from ecology to production results in the constant decline of the ecological security level and influences the regional sustainable development. Adjusting unreasonable land use mode and reconstructing natural land cover are important ways to maintain and improve the ecological environment. Also reclaiming farmland as areas for forests and grasslands （FRFG） is another way. Successful implementation of FRFG in China is the result of comprehensive effect of the multi-scales driving forces. This paper analyses the driving forces of FRFG in China on a national （country） -regional （province） - local （county） - household （farmer） level scale, and the results are： driving forces at the national scale include ecological and food security and the western development of China; at the regional scale, ecological and economic benefits become the main factors to influence the dimension of FRFG under the same policy. The driving forces can be divided into 6 types： industrial structure adjustment, water source protection, flood prevention, the Three-Gorge Project protection, reduction of the amount of sediment flowing into the Yellow River and wind erosion desertification prevention. The driving forces at the local scale can be divided into 12 types with developing leading industries, increasing farmers＇ income and improving agricultural production conditions as the main types; at the household scale, the national policy meeting farmers＇ demands and the optimization of individual interests are all driving forces.     

Biodiversity and Saving the Earth

The challenges for reversing course in our stewardship of the earth's ecosystems has never been greater. Biodiversity is in decline on an unprecedented scale and it is tempting to use this as an indicator of the health of the earth's ecosystems. In fact it is one of a number of indicators that collectively provides information on trends in the condition of ecosystems. But the larger problem is the lack of integration between the social and natural sciences. Mainstream scientists continue to reject the notion that solving environmental problems requires an integration of values and processes. A conceptual model shows how these facets may be brought together. A holistic vision requires the integration of natural, social and health sciences. From this perspective the linkage between biodiversity, ecosystem resilience and management options is more clearly articulated.     

森林对污染物（SO2-4）的过滤器效应研究

森林的过滤器效应是指森林对污染物所具有的净化缓冲作用，这是森林生态系统所具有的重要生态服务功能之一。森林生态系统对污染物的截留、吸附与净化一般是通过污染物在森林生态系统中的乔木层与灌草层植物、枯落物和土壤（微生物）等组分间的转化过程来实现，阐明森林生态系统各组分对污染物的净化效应是正确评估森林过滤器效应的关键。系统综述了森林生态系统各组分对污染物净化效应的国内外主要研究成果，指明了目前该方面研究存在的问题和努力的方向,并指出目前国内已有的大多数研究还处于实验观测与现象揭示阶段，缺乏对过程与机理的深入研究，很少进行多因素的动态综合研究和系统分析，这都限制了我们对森林生态系统对污染物净化过程内在运行机制和客观规律的正确认识和评估。把整个森林生态系统当作一个过滤器，从植物、凋落物、土壤、微生物几个亚系统方面介绍了森林过滤器对污染物净化缓冲作用方面的主要研究进展。     

基于生产可能性边界的黄河三角洲湿地生态系统服务权衡强度

提出了一种基于生产可能性边界（PPF）的湿地生态系统服务权衡强度计算方法,包括湿地生态系统服务定量评估、权衡关系判定、PPF曲线绘制和权衡强度计算四个步骤。以黄河三角洲湿地为研究对象,对保护情景、现状发展情景及开发情景三种土地利用发展模式下的主导生态系统服务进行了定量化权衡分析。结果表明：各生态系统服务间呈现显著相关关系（R²≥0.9,P<0.01）,各发展情景下,栖息地质量与碳储量之间均为协同关系;物质生产与栖息地质量间均为权衡关系,排序为保护情景<基期<现状发展情景<开发情景;而对于物质生产与碳储量之间,在保护及现状发展情景下存在协同关系;而开发情景下转变为权衡关系。该模型通过灵活比较不同生态服务间权衡关系分析进行系列管理规划的方案优选,为实现区域可持续发展提供科学依据。     

Luoyang Dual Spatial Criterion Ecological City Construction

The construction of an ecological city has two foundational platforms： the small platform, namely urban district or simply called as ＂city ecosystem＂; and the big platform, namely around city district in certain region scope or also referred to as ＂city-region ecosystem＂. The construction of an ecological city must be launched in the dual spatial criteria： in city （urban district） criterion--optimizing the city ecosystem; in city-region （city territory） criterion-optimizing the city-region ecosystem. Luoyang has the bright characteristic and the typical image within cities Of China, and even in the world. The construction of an ecological city in dual spatial criteria--the city and the cityregion has the vital significance to urbanization advancement and sustainable development in Luoyang. In city-region criterion, the primary mission of Luoyang＇s ecological city construction is to create a fine ecological environment platform in its city territory. In city criterion, the basic duty of Luoyang＇s ecologic city construction is to enhance the ecological capacity and benefit of the central city.     

岷江上游聚落分布规律及其生态特征——以四川理县为例

聚落是人类生存的重要空间形式，而聚落生态系统是人类生态系统的基本功能单位。山区聚落生态系统是山区人地关系的集中反映。岷江上游既是一个多民族聚居区，又是典型的生态环境脆弱区。岷江上游特殊的地理环境和生态条件 决定了聚落垂直分布的超常规性及其与自然垂直生态带的适应性。生态脆弱区聚落的发展受到耕地、能源和水资源的制约。聚落生态系统是区域生态系统的重要组成部分。聚落生态系统质量的提高既有赖于区域环境的改善，又可以为区域环境的改善创造条件。目前，由于人口的大量增加，人类活动的加剧，岷江上游聚落生态系统面临着更加严峻的生态和经济问题。要解决这些问题，除采取区域性的措施外（如停止对天然林的砍伐），还必须在聚落生态系统的水平上采取适当的对策。     

On the Problem of Assessing the Resistance of Planktonic Community to Adverse Influences

An experimental-analytical method for assessing the vulnerability of aquatic ecosystems under conditions of anthropogenic pollution is considered. Such data are very important for estimating economic damage from accidental environmental pollution and determining the seasons in which industrial activities will be less hazardous in ecological terms. A feasible approach to this problem is based on the study of ecosystem behavior under critical conditions. Phytoplankton, being the main primary producer of organic matter in the aquatic ecosystem, is the key element providing for its stability.__________Translated from Ekologiya, No. 4, 2005, pp. 294–299.Original Russian Text Copyright © 2005 by Domnin, Korsak, Mosharov.