关于义县生态环境保护与建设方案

根据义县生态环境的现状及存在的问题，运用生态学原理，提出了水土保持与退耕还林还草、水资源保护与科学利用、农村能源建设、村屯生态建设、发展生态农业经济、自然保护区建设等相应的建设方案。     

From Valuation to Governance: Using Choice Experiment to Value Street Trees

This paper reports a choice experiment used to estimate the value of street trees in the city center of Lodz, Poland, and the broader context of how valuation results helped to improve governance of urban ecosystem services in this city. Based on a simplified inventory of trees, we prepared a set of hypothetical programs which put varying emphasis on the different ways to increase the numbers of trees, along with different levels of a hypothetical tax that would have to be paid by respondents to implement a given program. Our study indicated that the 351 surveyed Lodz residents were willing to pay the highest price for greening those streets where currently there are few or no trees and confirmed the general importance of planting trees. The results provided an argument in the debate on the new development strategy for the city and helped to promote the concept of ecosystem services.     

基塘水产养殖对水域氮磷的影响

基塘系统是一种相对封闭的人工生态系统，其鱼塘子系统中的营养盐－氮、磷既是鱼类生长的必需元素，又是水体中的限制性元素。氮、磷的变化受塘中水生生物活动（如光合作用、呼吸、排泄）、鱼类粪便、饲料投加、底泥等的影响，文中对基塘中氮磷的变化及影响因子进行探讨。     

我国东部矿区生态系统退化机理初探

煤炭开采已经给矿区生态系统带来了极大的危害，使矿区生态系统的生产力不断下降，矿区生态系统正在发生退化。华东地区是我国的主要煤炭产区，该地区为高潜水位区域，因此该地区的生态退化具有其独特性，地表塌陷引起的土壤盐渍化、地面积水、水土流失等是引起这一地区生态系统退化的主要原因。     

生态系统服务的核算方法

生态系统服务是指对人类生存及生活质量有贡献的生态系统产品和生态系统功能 ,包括由自然生态过程产生并维持的环境和资源条件。目前已有的生态系统服务核算方法可以分为市场价值法、替代市场法和假想市场法。     

Application of a systemic approach to the study of pollution of the Tinto and Odiel rivers (Spain)

The province of Huelva in the SW of Spain presents high environmental contrasts: together with the great abundance of natural spaces, it shows the impacts of historical natural resources exploitation processes. In the Ria of Huelva, the effluents of the chemical industries must be added to the contaminating inputs of the Tinto and Odiel rivers, coming from the acid drainage of the mines located in the Iberian Pyrite Belt. This forced the Environmental Agency (AMA) to elaborate in 1987 an Effluent Remediation Plan in order to negate unacceptable environmental impacts. The application of a grey box systemic analysis to the AMD pollution, undergone by the Tinto and Odiel rivers has allowed to set a conclusive explanation of the sampling results observed for a period of 11 years, thus making available an overall view of the polluting process and, above all, an explanation of its partial aspects.     

二十年来渤海生态环境参数的演化和相互关系

通过系统分析近２０ａ来渤海中部海域３ａ（１９８２－１９８３，１９９２－１９９３，１９９８－１９９９年）１０航次的生态环境特征参数的变化，描述了变化趋势，初步讨论了各种特征参数之间的相互关系。研究发现，近２０ａ来，渤海中部营养盐的浓度和结构（Ｎ／Ｐ和Ｓｉ／Ｎ）均发生显著变化，表现为：硝酸盐、亚硝酸盐、总无机氮持续增加，活性磷和硅显著降低，Ｎ／Ｐ值升高，Ｓｉ／Ｎ值下降。Ｎ／Ｐ值３ａ的五月和十月平均值分     

A General Equilibrium Model of Ecosystem Services in a River Basin

This study builds a general equilibrium model of ecosystem services, with sectors of the economy competing for use of the environment. The model recognizes that production processes in the real world require a combination of natural and human inputs, and understanding the value of these inputs and their competing uses is necessary when considering policies of resource conservation. We demonstrate the model with a numerical example of the Mississippi‐Atchafalaya river basin, in which grain production in the upper basin causes hypoxia that causes damages to the downstream fishing industry. We show that the size of damages is dependent on both environmental and economic shocks. While the potential damages to fishing are large, most of the damage occurs from economic forces rather than a more intensive use of nitrogen fertilizers. We show that these damages are exacerbated by increases in rainfall, which will likely get worse with climate change. We discuss welfare effects from a tax on nitrogen fertilizers and investments in riparian buffers. A 3% nitrogen tax would reduce the size of the hypoxic zone by 11% at a cost of 2% of Iowa's corn output. In comparison, riparian buffers are likely to be less costly and more popular politically.     

三江源区草场生态恶化原因新解

上世纪60年代以来三江源区草场“三化”明显,生态恶化,究其原因,既有自然因素的影响,又有人类活动的作用。通过比较分析有测量记录的气温、降雨和年末牲畜存栏数、采金、挖虫草(Cordycepssinensis)规模的变化及其与草原植被覆盖度变化的关系,文章为人为成因说提供了更为翔实可靠的证据。结论:超载是1957—1979年间、采金子和挖虫草是1980—2004年间草场生态恶化的主要原因。     

交际教学法在大学英语教学中的应用

交际法已经发展成为一种世界规模的外语教学理论和教学方法,成为当今世界各国外语教学界普遍承认和接受的基本原则.通过对交际教学法的进一步研究分析,叙述了什么是交际教学法,阐述了运用交际教学法组织大学英语教学的模式和交际教学法在大学英语教学中的运用,指出教师应充分运用交际教学法的基本原理更好地来提高中国英语教学水平.