Environmental and economic impacts of decision-making at an arable farm: an integrative modeling approach

This study examines the dependency between physical and anthropogenic systems in arable farming. The dynamic simulation model, which has its methodological origins in the modeling traditions of environmental systems analysis and microsimulation, reproduces the mutual links between the physical flows (e.g. energy, materials, emissions, and products), the farmer as a decision-making agent, and structural conditions influencing the farm. In running the model, the intention is to answer the question: What are the impacts on profitability and the environment (i.e. greenhouse gas effects, eutrophication, acidification, and energy use) of variations in prices, subsidies, the farmer's environmental values, and the farmer's skill in making production allocation choices? The results of the model simulations indicate, for example, that in terms of economic performance, a farmer can choose between two relatively sustainable strategies--either to specialize in organic production (thereby benefiting from higher subsidies and output prices), or to focus on conventional cultivation and use of pesticides and fertilizers (thereby benefiting from large yields). Regarding environmental impacts, there was no clear-cut divide between organic and conventional farming due to difficulties in allocating the use of manure. This finding is essentially related to the choice of system boundary, which is thoroughly discussed in the paper.     

电镀污泥的处理和综合利用研究进展

介绍了电镀污泥的产生、危害、主要处置和综合利用技术及其优缺点。提出回收重金属、优化传统固化技术、开发药剂稳定化新技术以及建立专业工厂是我国处理和利用电镀污泥的发展方向。     

global warming — uncertainties,effects, and policy options

Environmental policy making is a challenging task. Often the scope of an issue is not fully comprehended, and its future impact is even less well understood. Global warming is one of these environmental issues. The issue is made more complex because, first, there is a question of whether it is a problem at all and, second, unilateral policy making by one nation may not be sufficient or even significant to tackle the problem globally. This article outlines the scientific factors that contribute to global warming and discusses the uncertainties involved. The authors then discuss the ramifications of taking action (policy making) and failing to act (doing nothing) against the background of global warming, greenhouse gases, and cost-benefit analysis. The article concludes by reporting the results of a multidisciplinary panel of experts composed of scientists, economists, and policy analysts who commented on various policy options.     

空气动力阴影区对高层建筑周围污染物浓度分布的影响

空气动力阴影区是在风的作用下建筑物背风侧和顶部的旋涡区。当建筑物附近有污染源存在时，污染物的浓度分布与污染源和空气动力阴影区之间的相对位置有着密切关系。以一高层建筑为例，采用数值模拟的方法，探讨和分析污染源在空气动力阴影区内外几个不同相对位置时，建筑物周围污染物分布的不同。     

SCALE PROBLEMS IN INTERDISCIPLINARY WATER RESOURCES INVESTIGATION1

ABSTRACT The problems encountered in estimating scale parameters in interdisciplinary watershed research are discussed. Meteorology, hydrology, geology and water quality are discussed with respect to their individual strengths and weaknesses when applied to different scale problems. Areas where incompatibilities exist are pointed out and suggestions are made for effecting compromise. A watershed scale of roughly a hundred acres may be the scale at which all disciplines can effect optimum interaction.     

Armoured spiderman: morphological and behavioural adaptations of a specialised araneophagous predator (Araneae: Palpimanidae)

In a predator–prey system where both intervenients come from the same taxon, one can expect a strong selection on behavioural and morphological traits involved in prey capture. For example, in specialised snake-eating snakes, the predator is unaffetced by the venom of the prey. We predicted that similar adaptations should have evolved in spider-eating (araneophagous) spiders. We investigated potential and actual prey of two Palpimanus spiders (P. gibbulus, P. orientalis) to support the prediction that these are araneophagous predators. Specific behavioural adaptations were investigated using a high-speed camera during staged encounters with prey, while morphological adaptations were investigated using electron microscopy. Both Palpimanus species captured a wide assortment of spider species from various guilds but also a few insect species. Analysis of the potential prey suggested that Palpimanus is a retreat-invading predator that actively searches for spiders that hide in a retreat. Behavioural capture adaptations include a slow, stealthy approach to the prey followed by a very fast attack. Morphological capture adaptations include scopulae on forelegs used in grabbing prey body parts, stout forelegs to hold the prey firmly, and an extremely thick cuticle all over the body preventing injury from a counter bite of the prey. Palpimanus overwhelmed prey that was more than 200% larger than itself. In trials with another araneophagous spider, Cyrba algerina (Salticidae), Palpimanus captured C. algerina in more than 90% of cases independent of the size ratio between the spiders. Evidence indicates that both Palpimanus species possesses remarkable adaptations that increase its efficiency in capturing spider prey.     

Whole genome amplification and microsatellite genotyping of herbarium DNA revealed the identity of an ancient grapevine cultivar

Reconstruction of the grapevine cultivation history has advanced tremendously during the last decade. Identification of grapevine cultivars by using microsatellite DNA markers has mostly become a routine. The parentage of several renowned grapevine cultivars, like Cabernet Sauvignon and Chardonnay, has been elucidated. However, the assembly of a complete grapevine genealogy is not yet possible because missing links might no longer be in cultivation or are even extinct. This problem could be overcome by analyzing ancient DNA from grapevine herbarium specimens and other historical remnants of once cultivated varieties. Here, we present the first successful genotyping of a grapevine herbarium specimen and the identification of the corresponding grapevine cultivar. Using a set of nine grapevine microsatellite markers, in combination with a whole genome amplification procedure, we found the 90-year-old Tribidrag herbarium specimen to display the same microsatellite profile as the popular American cultivar Zinfandel. This work, together with information from several historical documents, provides a new clue of Zinfandel cultivation in Croatia as early as the beginning of fifteenth century, under the native name Tribidrag. Moreover, it emphasizes substantial information potential of existing grapevine and other herbarium collections worldwide.     

基于人工神经网络方法的河北省近海沉积物重金属污染综合评价

利用误差反相传播神经（BP）网络对河北省近海沉积物中的铅、镉、锌、汞、砷5种重金属元素的污染水平进行分析,利用自组织特征映射（SOFM）网络对上述重金属元素分布特征进行分类,通过分类与污染水平量化值的结合,进行综合评价。SOFM把52个沉积物样品分别划分为3、4、6类和9类。对比各种分类,分为3类的物理意义较明确。每个类别分别对应高中低不同的污染物浓度水平,差异显著、分类方式比较合理。通过此种分类可以判断河北省近海的沉积物重金属污染在不同海域存在一定的差别,整体上是离海岸越远,沉积物的重金属污染水平越高,距海岸较近的海域内,沉积物的重金属污染水平较低,但渤海湾内的重金属污染水平高于其他海域。     

Interaction Between Scientists and Nonscientists in Community-Based Watershed Management: Emergence of the Concept of Stream Naturalization

The authors' personal experience in watershed planning and decision making in the agricultural Midwest is described to illustrate how: (1) formalization of the process of community-based management is not sufficient to guarantee that local people will meaningfully consider scientific information and opinion when making decisions about watersheds, and (2) genuine social interaction between scientists and nonscientists requires a considerable investment of time and energy on the part of the scientist to develop personal relationships with nonscientists based on trust and mutual exchange of information. This experience provides the basis for developing a general conceptual model of the interaction between scientists and nonscientists in community-based watershed management in the agricultural Midwest. An important aspect of integrating science effectively into community-based decision making is the need to revise existing concepts to accommodate place-based contexts. Stream naturalization is introduced as an alternative to stream restoration and rehabilitation, which are viewed as inappropriate management strategies in human-dominated environments. Stream naturalization seeks to establish sustainable, morphologically and hydraulically varied, yet dynamically stable fluvial systems that are capable of supporting healthy, biologically diverse aquatic ecosystems. This general goal is consistent with the types of stream-management practices emerging from community-based decision making in human-dominated, agricultural landscapes. Further research on the linkages between geomorphological and ecological dynamics of human-modified agricultural streams over multiple spatial and temporal scales is needed to provide a sound scientific framework for stream naturalization.