Hybridization between wheat (Triticum aestivum) and the wild species Aegilops geniculata and A. biuncialis under experimental field conditions

Hybridization between Aegilops geniculata, A. biuncialis and bread wheat Triticum aestivum has been evaluated during two seasons under simulated field conditions to estimate the field hybridization rate under Central Spain conditions. The mean frequencies of hybridization between A. biuncialis and A. geniculata with wheat were 0.34% and 0.31%, respectively. Data from 10 hybrid plants for each combination showed that hybrids can be partially fertile by backcrossing with wheat parent, with percent averages of 3.17 grains/spikelets for A. biuncialis × wheat hybrids and 2.87 grains/spikelets for A. geniculata × wheat hybrids. Self-pollination, although at very low rates, was also possible in hybrids. The potential risks associated with natural hybridization in the context of transgenic wheat cultivation are discussed.     

Toxic metals in sewage sludge-amended soils: has promotion of beneficial use discounted the risks?

Land application of contaminated waste products has been defended as beneficial use by some scientists and regulators, based on the premise that the behavior of any toxins accumulated in soils from this practice is reasonably well understood and will not have detrimental agronomic or environmental impacts into the foreseeable future. In this review, I use the case of toxic metals in sewage sludges applied to agricultural land to illustrate that metal behavior in soils and plant uptake is difficult to generalize because it is strongly dependent on the nature of the metal, sludge, soil properties and crop. Nevertheless, permitted agricultural loadings of toxic metals from sewage sludges are typically regulated using the sole criterion of total metal loading or concentrations in soils. Several critical generalizing assumptions about the behavior of sludge-borne metals in soil-crop systems, built into the US EPA risk assessment for metals, have tended to underestimate risks and are shown not to be well justified by published research. It is argued that, in the absence of a basic understanding of metal behavior in each specific situation, a more precautionary approach to toxic metal additions to soils is warranted.     

加强生态农业建设是康平县脱贫致富的关键

对以发展康平县生态农业建设为主要措施，控制生态环境破坏，促进农村经济持续发展进行了系统的分析和阐述．并提出具体防治措施     

水生植物毒性试验及在生态风险评价中的作用

综述了利用大型水生毒性试验的主要技术和方法，地其在环境监测和评价中的特点进行分析，讨论了它在污染物生态风险评价中的作用和地位，并介绍国内外对水生植物生态毒理学研究和应用现状及发展趋势。     

废弃混凝土的开发利用

混凝土仍将是21世纪一种应用最广泛的建筑材料，但越来越多的拆除建筑物会产生大量的废弃混凝土块，既带来环境污染，又造成资源浪费。搞好废旧混凝土的开发利用，具有明显的环境效益和经济效益。     

应用地积累指数法评价太子河沉积物中重金属污染

本文根据沉积学原理和环境化学行为特点，应用地积累指数法对太子河（本溪段）沉积物中重金属污染进行了评价研究。结果表明，太子河市区段重污染是严重的，主要的重金属污染物为Ｃｕ、Ｐｂ，其次为Ｚｎ、Ｃｄ、Ｈｇ。     

综合评分指标体系在环境优先污染物筛选中的应用

介绍了一种用于环境优先污染物筛选的综合评分指标体系，并以上海市石化行业废气优先污染物的筛选为实例说明。     

环境价值评估方法综述

对目前国内外的环境价值评估方法进行了综述，并提出了一套适合我国国情的价值评估方法，该方法分为１４类２９个指标，作为完善我国环境价值评估体系的一种建议提出。     

潜在危害性指数法在筛选污染因子中的应用

介绍了潜在危害性指数法的基本原理和计算公式，通过某大型化工企业的实例，提出了应用的要求，并筛选出了企业的９项主要的环境监测因子。     

Fisheries management: integrating societal preference, decision analysis, and ecological risk assessment

Fisheries management is the practice of analyzing and selecting options to maintain or alter the structure, dynamics, and interaction of habitat, aquatic biota, and man to achieve human goals and objectives. The theory of fisheries management is: managers or decision makers attempt to maximize renewable `output' from an aquatic resource by choosing from among a set of decision options and applying a set of actions that generate an array of outputs. Outputs may be defined as a tangible catch, a fishing experience, an existence value, or anything else produced or supported by renewable aquatic resources. Overall output is always a mix of tangible and intangible elements. However defined, management goals and objectives are essential components of fisheries management or any other field of renewable natural resource management. Reaching consensus on management goals and objectives has never been a simple task. Beyond the broad and often conflicting goals of an agency, managers must decide who should set specific management objectives — agency personnel, the public, or a combination of the two. Historically, rhetoric aside, fisheries managers in North America nearly always have consulted with professionals in governmental roles to set management objectives. In a strongly pluralistic society, this often resulted in protracted political and legal conflict. Increasingly, there are calls for use of risk assessment to help solve such ecological policy and management problems commonly encountered in fisheries management. The basic concepts of ecological risk assessment may be simple, but the jargon and details are not. Risk assessment (and similar analytical tools) is a concept that has evoked strong reactions whenever it has been used. In spite of the difficulties of defining problems and setting management objectives for complex ecological policy questions, use of risk assessment to help solve ecological problems is widely supported. Ecological risk assessment will be most useful (and objective) in political deliberations when the policy debate revolves around largely technical concerns. To the extent that risk assessment forces policy debate and disagreement toward fundamental differences rather than superficial ones, it will be useful in decision making.