Summer total phosphorus in lakes: A map of Minnesota,Wisconsin, and Michigan,USA

A map of summer total phosphorus in lakes has been compiled for Minnesota, Wisconsin, and Michigan to clarify regional patterns in attainable lake trophic state. Total phosphorus was used as a measure of lake trophic state because: (1) phosphorus plays a central role in controlling the overall fertility of most lakes, (2) total phosphorus values are available for a great number of lakes, and (3) phosphorus is measured in a consistent manner. The maps were compiled using patterns of total phosphorus data and observed associations between these data and geographic characteristics including physiography, land use, geology, and soils. Regions depicted on the map represent areas of similarity in phosphorus concentrations in lakes, or similarity in the mosaic of values, as compared to adjacent areas. Within each region, differences in total phosphorus can be compared to natural and anthropogenic factors to determine the types of lakes representative of each region, the factors associated with differences in quality, and the realistically attainable phosphorus levels for each type of lake.     

长江三角洲的区域特点与产业结构

长江三角洲是我国最大的经济核心区，它的发展对于长江流域乃至全国都有重要意义，针对长江三角洲的区域发展特点与产业结构现状进行了分析，找提出了产业结构的调整意见。     

长江三角洲区域发展及区域互动的三大关键问题

在我国加入WTO、进入国际经济大循环的背景下，长江三角洲不仅要加强自身的发展，通过体制创新、技术创新建成为我国区域功能完善、产业布局合理、城乡关系协调、生态与环境优良的现代化示范区，更重要的是在长江流域和全国发挥经济带动作用，提高服务功能，成为我国与世界经济接轨并参与竞争的基地、我国高新技术产业与现代农业基地和支援西部大开发并提供知识经济服务的基地。但是长期的计划体制造成的地区分割与部门分割不利于产业的合理布局与重大基础设施建设的统一协调，也不利于共同进行生态建设与环境保护。从区域互动的角度就经济增长方式与产业布局、以港口为主的重大基础设施建设与协调、水土资源的环境保护与可持续发展三个方面进行了论述。     

AHP法在区域矿产资源综合经济评价中的应用

本文运用AHP法对某省20种主要矿产进行了综台经侪评价,确定了该省经济优势矿产、潜在优势矿产和劣势矿产,为制定该省矿产资源开发战略提供了科学依据。     

特大型矿产资源开发与区域经济发展——以西藏玉龙铜矿资源开发为例

矿产资源,特别是特大型矿的开发对区域经济发展具有重要的带动作用。西藏玉龙铜矿在国内仅次于德兴铜矿的特大型矿山,它的开发具有重大战略意义,有利于带动昌都地区经济的发展,本文认为开发玉龙铜矿既面临着矿产资源开发机制、模式及矿产开发区功能与结构等一系列重大变革,又出现许多有利条件和不利因素。必须面向下一世纪和国内外两个市场,按照新的机制,选择融合式发展,努力建立一个综合功能型的昌都地区经济。     

MONTHLY RUNOFF DISTRIBUTION RELATED TO BASIN GEOGRAPHY1

ABSTRACT: Mean monthly runoff from ungaged drainage basins that have significant snowpacks each year can be estimated quite well by assuming that the time duration between snowfall and snowmelt is the predominant factor in temporal runoff distribution. That time span is related to basin temperatures which are, in turn, functions of basin elevation and latitude. Regional hydrologic analyses of gaged basin data create regression equations for estimating runoff distribution by month. These equations then can be applied to ungaged basins. Basin latitude and mean elevation are two independent variables that can be used in estimating monthly runoff distributions.     

PHYTOPLANKTON PRODUCTIVITY AND BIOMASS IN THE CHARLOTTE HARBOR ESTUARINE SYSTEM,FLORIDA1

ABSTRACT: Phytoplankton carbon-14 productivity at a depth of 50 percent of surface light and chlorophyll-α concentrations were measured every other month from November 1985 through September 1986 at 12 stations in the Charlotte Harbor estuarine system. Maximum productivity and chlorophyll-α concentrations occurred during summer or early autumn near the mouths of tidal rivers. Most of the variability in light-normalized productivity and chlorophyll-α could be attributed to two factors derived from Principal Component Analysis of ambient water-quality characteristics. One factor related to seasonal variability and the other to spatial variability. The seasonal factor incorporated the interaction of temperature and nutrients. The spatial factor incorporated the interaction of salinity, nutrients, and water color that resulted from the mixing of freshwater inflow and seawater. Although freshwater inflow increased the availability of nutrients in low salinity (less than 10‰) waters, the highly colored freshwater restricted light penetration and phytoplankton productivity. Maximum productivity and biomass occurred where color associated with the freshwater inflow had been diluted by seawater so that light and nutrients were both available. Concentrations of inorganic nitrogen were often at or below detection limit throughout most of the high salinity (greater than 20‰) waters of the estuary and was probably the most critical nutrient in limiting phytoplankton productivity.     

Metbodology of environmental impact assessment for regional development

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区域开发环境影响评价与区域环境规划

论述了区域开发环境影响评价与区域环境规划的概念、基本原则，提出了工作程序并对主要部分进行了分析。     

GM(1,1)模型预测城市区域环境噪声的应用

介绍了重庆市主城区区域环境噪声污染现状,根据1996～2002年区域环境噪声的监测数据,建立了GM(1,1)灰色预测模型,通过预测探讨了区域环境噪声的变化规律.结果表明,主城区未来几年区域环境噪声呈上升趋势,2003年预测值为57.8分贝.