Water supply and sanitation services for all: global progress during the 1990s

The Earth may be largely covered with water, but over one billion people are estimated to be without safe drinking water and almost 2.5 billion (40% of the world's population) without adequate sanitation at the outset of the new millennium. The provision of safe water and sanitation for all poses several serious institutional and economic challenges at international, national and local levels. Despite the various political commitments made from the late 1970s onwards, these commitments have remained largely unfulfilled. Even though some efforts to expand coverage have been made over the past two decades, much of those efforts have been undermined by socioeconomic problems and growing population, particularly in the urban areas of developing countries. The water supply and sanitation sector is actually in acute need of new investments for expansion and maintenance of facilities. Nonetheless, some positive trends can be discerned, such as, for example, the increasing recognition of integrated water resources management, environmental sanitation, public-private partnerships and women as a key for improvement and expansion of services.     

岷江生态环境问题及其对策研究

本文主要探讨岷江流域的生态环境问题及其对策。全文分为两个部分。(1)研究岷江生态环境问题;(2)解决岷江生态环境问题的主要对策。     

充分利用水资源 改善生态环境

本文结合攀枝花地区实际,论述了水资源利用率高低是影响经济发展和改善生态环境的重要因素,调查分析了攀枝花地区水资源利用率低的原因;提出了提高水资源利用率的对策和措施。为促进经济发展和改善生态环境提供了依据。     

Economics and energetics of organic and conventional farming

The use of organic farming technologies has certain advantages in some situations and for certain crops such as maize; however, with other crops such as vegetables and fruits, yields under organic production may be substantially reduced compared with conventional production. In most cases, the use of organic technologies requires higher labor inputs than conventional technologies. Some major advantages of organic production are the conservation of soil and water resources and the effective recycling of livestock wastes when they are available.     

THE POLITICAL INFLUENCE OF RESIDENTIAL CONSUMERS ON WATER RATES1

ABSTRACT: The regulatory process such as that for water rates can be viewed as a bargaining process between regulators, utility management, and consumers. This bargaining process involves both political and economic influences. In an attempt to empirically verify that utility rates are a product of both economic and political factors, a sample of publicly-owned water utilities was subjected to regression analysis. As expected, cost and cost-related factors were positive and significant determinants of residential water rates. Using an admittedly imperfect measure of residential user political influence, there was evidence that increased political activity results in lower water rates. Furthermore, the political influence and water rate linkage is more evident in small water utilities than in larger suppliers.     

Degradation of Polylactic Acid (PLA) Plastic in Costa Rican Soil and Iowa State University Compost Rows

In this study the degradation of polylactic acid (PLA) plastic films in Costa Rican soil and in a leaf composting environment was investigated. Three types of PLA films were used: Ch-I, (PLA monolayer plastic films from Chronopol, Golden, CO), GII (PLA trilayer plastic films from Cargill Dow Polymers LLC, Minnetonka, MN), and Ca-I (PLA monolayer plastic films from Cargill Dow Polymers LLC). The average soil temperature and moisture content in Costa Rica were 27°C and 80%, respectively. The average degradation rate of PLA plastic films in the soil of the banana field was 7675 M _w/week. Two compost rows were set up at the Iowa State University (ISU) (Ames) compost site. Temperature and relative humidity of the compost rows were kept at 55 ± 5°C and 50 ± 10% RH, respectively. The degradation rates of GII and Ca-I in the compost rows were 113,290 and 71,283 M _w/week, respectively. Therefore, it was estimated that in Costa Rican soil and in compost rows, PLA would be visibly degraded in 6 months and in 3 weeks, respectively.     

厄尔尼诺、拉尼娜对全球生态环境及中国1998夏季洪灾的影响

本文概述了厄尔尼诺和拉尼娜现象的形式和成因,讨论了其对气候异常、全球生态环境和中国１９９８ 夏季特大洪灾的重要影响,结果表明,作为海气耦合的厄尔尼诺、拉尼娜现象对环境异常和洪灾有着特别重要的作用。     

广元飞播造林成效与流域生态环境效益研究

运用川北广元历年飞播成效调查以及固定标准地观测的结果,结合笔者从事飞播造林技术与管理工作的经验,得出：飞播造林是速度快、省劳力、投资少、成本低、效益高的造林方式,推广飞机播种造林是绿化川北山地,迅速治理流域生态环境和实现山区经济可持续发展的有效措施     

中国脆弱生态区可持续发展指标体系框架设计

本文分析了我国脆弱生态区人口—资源—环境与发展的矛盾,探讨了我国典型脆弱生态区可持续发展指标体系建立的指导原则和方法,提出了我国典型脆弱生态区可持续发展指标体系     

实施《全国生态环境建设规划》的基本思路

良好的生态环境是可持续发展的重要前提条件,为了实施好《全国生态环境建设规划》,本文从组织层面、管理层面、法规层面,提出了实施的基本措施