Analysis and improving ways for water condition in winter wheat field of dryland in subhumid areas of the loess plateau

Based on the soil moisture data from the locating experiments from 1986-1990, and using the water balance method, the water supply and demand state in the field of winter wheat, and the ways for improving water condition in dryland of subhumid by dry area of the Loess Plateau were studied. The results suggested that a low precipitation satisfying ratio of 42.9%-58.8% appears in the growing period of winter wheat, and the yield, to a great extent depends on the water that was stored in deep soil layer in the previous rainy season. The filed trial results showed that tillage in the summer fallow period,straw cover, soil moisture regulation with adequate fertilization, crop rotation and proper croppingsystem could be the efficient ways for improving the water condition,and for the exploitation and utilization of natural water resources(both precipitation and soil water) in the winter wheat field of dryland.     

长春市水资源可持续发展研究对策

在对长春市水资源概况及其开发利用现状进行简要分析的基础上，指出长春市水资源开发利用中的一些问题，并提出了水资源优化配置、建立水市场机制、加强节约用水、发展污水回收再利用等近远期水资源可持续利用对策。     

南方涝渍地区退田还渔的一个实例分析

以江汉平原四湖涝渍地区的一个经围湖造田形成的典型农业微域为研究对象,在对其土壤和作物生长状况进行调查的基础上,探讨了退田还渔的必要性与具体方案。结果表明,对小型湖泊通过围湖造田所形成的农业微域,在人工排水和土地平整不充分的情况下,其地貌和土壤还残留有原有湖泊的影响,处于原湖泊低处的土壤表现出明显的沼泽化和严重潜育化的特征。在该地区种植水稻产量比正常地区减产达16%～26.8%。利用数量化理论Ⅰ确定了该地区适宜退田还渔的具体位置和面积。按照这一方案实施的结果,该地区从1997～2001年的5年中精养鱼塘面积增加9倍,养鱼的效益比种植水稻高5～10倍,还减轻了该地区夏季和冬季的排水压力。     

糖厂废醪液蔗地施肥的效应

糖厂根据当地的自然条件和工农关系 ,采用施肥法资源化利用废醪液 ,是最为经济的污水治理方法。     

现代测绘技术在解决矿区资源与环境问题中的应用探讨

以“３Ｓ”技术及其集成为代表的现代测绘技术在解决我国矿区存在的资源浪费及环境污染问题中具有重要的应用,本文对此进行了探讨。     

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.     

兖州矿区基地大气环境质量状况浅析

根据兖州矿区基地近6年的大气监测资料,对区域性大气质量状况进行了分析,并提出了改善大气质量的四条措施。     

新疆玛纳斯河流域农业水资源可利用潜力分析

结合新疆玛纳斯河流域水文水资源、种植结构和节水技术发展等资料,从开源、节流两方面对流域近期(至2010年)、中远期(2010-2030年)农业水资源极限潜力、可挖掘潜力进行了估算。结果表明,就目前水资源的利用水平和开发趋势,玛纳斯河流域未来农业水资源的主要利用途径是开源与节流相结合,以节流为主。全流域尚有的农业灌溉水资源极限潜力为10.75×10⁸m³,近期农业水资源可挖掘潜力为2.13×10⁸m³,其中开源增水潜力0.40×10⁸m³,占18.8%,节流增水潜力1.73×10⁸m³,占81.2%;中远期农业水资源可挖掘潜力5.33×10⁸m³,其中开源增水潜力1.12×10⁸m³,占21.0%,节流增水潜力4.21×10⁸m³,占79.0%。该研究对区域制订节水灌溉规划及水资源系统优化配置具有重要参考价值。     

干旱区城市水资源开发与环境保护

水资源是干旱区生态环境中最活跃的因子，城市是自然系统与人工系统耦合成的大系统，也是地下水高度集中开发的地区。地下水是干旱区城市的主要供水水源。文章从内蒙古自治区城市水资源供需现状出发，阐述了城市水资源开发带来的环境问题，重点探讨了城市地下水超采对周边地区环境的影响。最后提出了城市水资源开发与环境保护对策措施。     

山东省森林资源与木材供需平衡模型的建立与应用

本文在对山东省森林资源和木材供需平衡状况进行系统分析的基础上，利用系统动力学方法建立了山东省森林资源与木材供需平衡模型，通过对不同方案的政策仿真和结果分析，试图提出解决山东省木材供需矛盾的最佳途径，为制定林业发展政策提供依据。