AGRICULTURAL WATER MODELING AND ECONOMIC INFORMATION NEEDS UNDER THE MODEL WATER CODE1

ABSTRACT: Economic information for efficient water allocation is difficult and costly to acquire under administrative water systems evolving under the Model Water Code. One approach to obtaining more information is to use a simulator like the Florida AGWATER model. The advantage of AGWATER is the potential for realistic prediction, because it operates at the field and day levels, using detailed information for each crop and tract. Unfortunately, such simulators are complex and require large amounts of costly input data. A better solution to the information problem may be to use markets for the marketable goods associated with water, because information is inherent in such a process. This approach will allow limited modeling and management resources to be put into using water models to generate information for the goods dependent on water that are difficult to market, like wildlife services.     

武汉市大旅游网络建设研究

从地理位置、对外经济联系、国内和省内经济地位、旅游资源丰度等方面分析了武汉市发展旅游事业的有利条件；论证了建设以武汉市为中心，向郊区（县）、省内和邻省延伸的旅游网络的必要性和可行性及发展国际旅游的潜力；提出了大力加强景点和基础设施建设，改善周边交通条件，壮大地方航空公司等加快旅游业发展的对策和措施。     

新排污收费条例对燃煤电厂的影响探析

《排污费征收和管理条例》(简称新《条例》)的实施是我国排污收费制度的重大变革，对相关行业将产生不同程度的影响。着重分析了新《条例》的实施对燃煤电厂的不利影响，以及对企业增加环保投入治理污染的推动作用。     

榆林地区能源基地建设水资源保证程度及供水措施

榆林地区是我国重要的能源基地，水资源贫乏是影响该地区工业发展的重要因素。本文通过对区内水资源及其开发利用条件、供需平衡分析后认为，只要兴建水库，调节径流及加强污水处理，增加区域供水能力，区内水资源可以基本满足近阶段经济发展的用水需求。     

我国电子废弃物现状研究

依据我国家电生产消费数据,对我国电子垃圾产生量进行了预测,认为中国目前正处于电子垃圾高速增长期。通过对电子废弃物处理技术现状的介绍和对我国电子废弃物处理现状的分析,认为我国电子废弃物处理仍处于很低的水平,目前我国符合环保和市场要求的电子废弃物处理企业不能满足我国目前电子废弃物快速增长的需要,迫切需要开发符合我国国情、有市场竞争力的电子废弃物处理工艺。贵稀金属作为国民经济发展不可缺少的资源,随着资源的开采,矿床的贫乏,开采成本的提高,从电子废弃物中回收贵稀金属将具有长远的战略意义。     

论政府抓农业的重点所在

针对当前地方政府偏重于高利润农业项目，导致“三高”农业重点旁移的现象，阐述政府抓农业重点的必要住，指出其重点在于：（１）抓调查研究，抓政策；（２）抓农业教育与农业科研；（３）抓既带战略性而农民又力所不及和缺乏积极性的项目；（４）抓农技推广机构和队伍．而高利润的农业项目可由市场来调节．并从发展“三高’农业的需要以及当前出现的农民单施化肥的短期行为、人均耕地面积下降、地力下降、丢荒弃耕的情况等方面阐述政府重点抓培肥地力的重要性．     

Self-organized digging activity in ant colonies

Many ant species adjust the volume of their underground nest to the colony size. We studied whether the regulation of the volume of excavated sand could result from an interplay between recruitment processes and ant density. Experiments were performed with different group sizes of workers in the ant Messor sancta. When presented with a thin homogeneous sand disk, these groups excavated networks of galleries in less than 3 days. The excavation dynamics were logistic shaped, which suggests the existence of a double feedback system: a positive one resulting in an initial exponential growth phase, and a negative one leading the dynamics to a saturation phase. The total volume of excavated sand was almost proportional to the number of workers. We then developed a model in which we incorporated the quantitative behavioral rules of the workers digging activity. A positive feedback was introduced in the form of a recruitment process mediated by pheromones. The model predicts that the excavation dynamics should be logistic shaped and the excavation should almost stop despite the absence of any explicit negative feedback. Moreover, the model was able to reproduce the positive linear relationship between nest volume and colony size.Communicated by K. Ross     

高炉煤气袋式除尘系统的问题及改进

钢铁生产会产生大量的煤气.袋式除尘是高炉煤气除尘的发展方向.对重钢高炉煤气袋式除尘系统问题的分析研究结果表明:要使钢铁企业煤气除尘系统更高效、低耗、环保的运行,必须采用灵活、可操作性强的煤气温度调节手段,选择适宜的阀门和喷吹控制方式,优化除尘灰的保温模式和卸灰设备的结构等.     

Dioxins and related compounds: Status and regulatory aspects

Several countries have put much effort in dioxin research programmes with the aim to assess the risks of dioxin exposure, to identify dioxin sources and to quantify their contribution to environmental emissions and human exposure. In this review, the accent has been put on: sources of dioxins and their contribution to the total dioxin emissions, sources of human exposure and their contribution to exposure and measures to reduce emission and exposure. The information from countries with existing dioxin regulations is reviewed and compared. Uncertainties which hamper comparability of data are indicated. Results of measures and expectations for the near future are presented.     

燕麦对盐碱胁迫的反应和适应性

研究了自然盐碱胁迫对燕麦植株生长、水势、渗透调节物质质量分数以及对K 、Na 选择性吸收的影响,结果表明,随着土壤盐碱胁迫的增强燕麦植株生长受抑,叶片和根系的水势较对照均有所降低,其中裸燕麦较皮燕麦水势下降幅度大,表明裸燕麦比皮燕麦对盐碱胁迫更敏感。燕麦叶片内脯氨酸和可溶性糖累积。随着土壤盐碱胁迫的增强植株对Na 的吸收增加,对K 的吸收受到抑制,从而使w(Na )/w(K )和SNa K 值升高。在盐碱胁迫下,燕麦是以合成和积累有机溶质(脯氨酸和可溶性糖)以及吸收和积累无机离子(Na )来进行渗透调节,以适应盐碱胁迫。