金沙江流域水土流失与人类活动影响分析

长江三峡水利枢纽工程能否正常发挥效益，泥沙是重要的制约因素之一，而水库的泥沙主要来自上游金沙江，其多年平均输沙量占入库寸滩站的５２７％。因此，本文对金沙江泥沙的地区组成、水土流失及人类活动影响等问题进行了深入的分析，并提出了防治对策。     

HUMAN STABILITY IN A HIGH FLOOD HAZARD ZONE1

ABSTRACT: The delineation of high flood hazard zones within a flood plain is usually independent of the hydraulic parameters that constitute a life threatening situation. In order to define human instability in high hazard areas, a study was conducted to identify when an adult human could not stand or maneuver in a simulated flood flow. An analysis was performed on a rigid body monolith resulting in a toppling hazard envelope curve (velocity vs. depth). A 120 lb monolith was then constructed and tested to relate the actual flow velocity and depth at toppling to theory. A series of human subjects (90–201 Ibs) were placed in a recirculating flume and tested to determine the velocity and depth of flow that caused their instability. The test results determined that the product number, which is the product of the velocity and depth at toppling of the monolith, closely compared to the theoretical envelope curve. The monolith results represent the lower limit of human stability. Also, the product number appeared to be a predictor of human instability in flood flow. A relationship was developed to estimate the product number at which a human subject becomes unstable as a function of the height and weight of the subject.     

Quantitative Analyses of Pollution-Indicator and Pathogenic Bacteria in Mumbai Waters from Ballast Water Exchange Perspective

As large numbers of ships either take in ballast from or discharge their ballast into the Mumbai Harbor region, it is pertinent to quantify microorganisms of health concerns and suggest on the suitability of water for ballasting purposes. To meet with this main aim, a selected set of general and pathogenic bacterial groups and their seasonal variations were studied from the Mumbai Harbor area. Sampling was carried out during postmonsoon (November 2001), pre-monsoon (April 2002) and monsoon (October 2002) periods. We quantified total coliforms and eight other groups of known human pathogenic bacteria from water, sediment, marine plant and animal samples collected in and around Mumbai Harbor. When compared with similar studies from other parts/harbors of the world, the Mumbai Harbor area has over 100-times higher levels of coliforms. The serotypes of Escherichia coli O157 and Shigella-Alkaligens Dispar group were abundant throughout the year. Even Vibrio cholerae, V. parahaemolyticus, Salmonella spp., campylobacters and aeromonads were present in large numbers. This comprehensive study, conducted with a view to quantify these bacterial groups and to evaluate the suitability of these waters for ballasting purposes, clearly suggests that both ballasting and deballasting be avoided in this region and alternative procedures should be developed for treating/handling ballast water.     

Rational forest productivity decline

A whole forest optimisation model was employed to examine economic behaviour as it relates to long term, forest productivity decline in the boreal forests of Ontario, Canada. Our productivity investment model(PIM) incorporated a choice between productivity decline as representedby a drop in forest Site Class, and a fee to 'maintain' site productivity. Sensitivity analysis was used to determine the point at which these fees exceeded the value of the differential in timber volume between upper and lower site classes. By varying discount rate, 'productivity investment frontiers' were constructed, which highlight the effects of the magnitude in productivity decline, maintenance fees, and harvest flow constraints upon the occurrence and schedule of productivity declines. In presenting this simple approach to exploring the effects of economic choice upon forest productivity decline, the phenomena of 'natural capital divestment' within forestry is described.     

Social goals and the valuation of natural capital

Valuation ultimately refers to the contribution of an item to meeting a specific goal or objective. Conventional economic valuation is based on the goal of allocative efficiency. But other social goals may be equally, if not more, important. For example, the goals of social fairness and ecological sustainability have been identified as being at least of the samelevel of importance as allocative efficiency. This paper looks atthe role of social goals in determining the basis for valuation ofnatural capital and ecosystem services, and sketches the characteristics of a system of valuation that would give equal weight to all three of the major social goals mentioned above. It also places these goals within a more comprehensive conceptualmodel of the economy and its relationship to the ecological lifesupport system in which it is embedded.     

Measuring the wealth of nations

The sustainability of development is closely linked to changes intotal per capita wealth. This paper presents estimates of the wealth of nations for nearly 100 countries, broken down into produced assets, natural resources and human resources. While thelatter is the dominant form of wealth in virtually all countries,in low income natural resource exporters the share of natural resources in total wealth is equal to the share of produced assets. For low income countries in general, cropland forms thevast majority of natural wealth. The analysis suggests the process of development can be viewed as one of portfolio management: sustainable development entails saving the rents fromexhaustible resources, managing renewable resources sustainably,and investing savings in both produced assets and human resources.     

Use of Satellite Imagery as Environmental Impact Assessment Tool: A case Study from the Nw Egyptian Red Sea Coastal Zone

Knowledge and detecting impacts of human activities on the coastal ecosystem is an essential management requirement and also very important for future and proper planning of coastal areas. Moreover, documentation of these impacts can help in increasing public awareness about side effects of unsustainable practices. Analysis of multidate remote sensing data can be used as an effective tool in environmental impact assessment (EIA). Being synoptic and frequent in coverage, multidate data from Landsat and other satellites provide a reference record and bird’s eye viewing to the environmental situation of the coastal ecosystem and the associated habitats. Furthermore, integration of satellite data with field observations and background information can help in decision if a certain activity has caused deterioration to a specific habitat or not. The present paper is an attempt to utilize remote sensing data for assessment impacts of some human activities on the major sensitive habitats of the NW Egyptian Red Sea coastal zone, definitely between Ras Gemsha and Safaga. Through multidate change analysis of Landsat data (TM & ETM+ sensors), it was possible to depict some of the human infringements in the area and to provide, in some cases, exclusive evidences for the damaging effect of some developmental activities.     

东北平原西部沙地的气候变异与土地荒漠化

东北平原西部沙地位于欧亚大陆中纬度巨型沙带的东部边缘 ,为我国荒漠化土地的东缘。随着经济的发展 ,生态环境遭到严重破坏 ,荒漠化景观日益明显 ,前景令人堪忧。气候因素是荒漠化发展的一个基本因素 ,东北平原西部沙地是我国北方气候条件最好的沙区 ,但目前对于区域荒漠化驱动因子的气候因素影响方面的研究未开展系统的工作。论文系统分析了东北平原西部沙地影响荒漠化的现代气候因素特点 ,探讨了在较好气候条件下气候变异、人类活动与荒漠化之间的关系 ,并根据气候发展趋势预测了未来在自然因素作用下沙地的可能发展趋势。     

室内空气污染对人体健康影响与防护对策

介绍了室内空气污染的定义、室内空气中常见的污染物及其主要来源,分析了室内空气中主要污染物对人体健康的影响, 提出了保护室内环境的对策.     

The long-term impact of a man-made disaster: An examination of a small town in the aftermath of the Three Mile Island Nuclear Reactor Accident

This paper explores the long-term effects of a nuclear accident on residents' perceptions of their physical and mental health, their trust of public officials, and their attitudes toward the future risks of nuclear power generation In their community. We find that in the period after the accident at Three Mile Island that there are constant or Increasing levels of distress reported by community residents. We conclude that the effects of a technological disaster may often be more enduring than those natural disaster and that greater research efforts should be made to Investigate the long-term consequences of man-made catastrophies of all types.