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801.
/ The management of riverine wetlands, recognized as a major component of biodiversity in fluvial hydrosystems, is problematic. Preservation or restoration of such ecosystems requires a method to assess the major ecological processes operating in the wetlands, the sustainability of the aquatic stage, and the restoration potential of each riverine wetland. We propose a method of diagnosis based on aquatic macrophytes and helophytes. Plant communities are used because they are easy to survey and provide information about (1) the origin of a water supply (i.e., groundwater, seepage, or surface river water) and its nutrient content, (2) effects of flood disturbances, and (3) terrestrialization processes. The novelty of the method is that, in contrast to available typologies, it is based on the interference of gradients resulting from several processes, which makes it possible to predict wetland sustainability and restoration potential. These predictions result from knowledge of the processes involved in terrestrialization, i.e., the influence of flood disturbances, occurrence of groundwater supplies, trophic degree, and water permanency of the habitat during a yearly cycle. The method is demonstrated on five different river systems. 相似文献
802.
冬春季富营养化滆湖中沉水植被重建及净化效果 总被引:1,自引:0,他引:1
秋末冬初在富营养化滆湖的围隔中引种沉水植物,分别构建5种植被区、菹草-伊乐藻区、菹草区、伊乐藻区,调查4种区域内植被恢复及对水质的净化效果。结果发现菹草-伊乐藻区不仅能在冬春季节保持对营养盐较高的去除效果,并能在冬季有效缓解苦草等植物死亡(5种植被区)给水质带来的不利影响;菹草-伊乐藻区对比湖面敞开区域内TP,TN,NH3-N,Chl.a的去除率可达62.9%,31.5%,53.9%,46.1%,对CODMn的去除率仅为9.7%;比较各单种区:伊乐藻对TN的去除效果要好于菹草,菹草对TP的去除效果要好于伊乐藻。 相似文献
803.
Wei Wu Ji-long Chen Hong-bin Liu Axel Garcia y Garcia Gerrit Hoogenboom 《Agriculture, ecosystems & environment》2010,135(1-2):111-118
Soil and weather data are critical for the operation of crop simulation models. However, in many cases they are not readily available, especially applications at a regional or larger spatial scale. The Vegetation/Ecosystem Modeling and Analysis Project (VEMAP) provides massive quantities of geo-referenced soil and weather data variables on a half-degree latitude–longitude grid covering the conterminous USA. The VEMAP data were derived from a range of products and analyses, including ground observations, cluster analyses, kriging interpolation, and data assimilation. The objective of this study was to convert the soil and daily weather data of VEMAP into a format that can be used in the popular modeling software Decision Support System for Agrotechnology Transfer (DSSAT). Users can select appropriate soil or daily weather information for the area of interest. The conversion of the VEMAP data resulted in 5927 unique soil profiles and 3261 unique weather station files that encompass daily data from 1895 to 1993. To demonstrate the utility of this database in DSSAT, one representative county of the state of Georgia, USA was selected and a soybean simulation model was employed to simulate final yield using the extracted soil and daily weather data for the normal year (1961–1990). Meanwhile, the extracted daily weather data were compared with ground station observations from the National Weather Service Cooperative Observer Program (COOP). The paired t-test showed that no significant differences were found between the daily weather data and between simulated yields based on VEMAP and COOP weather data for the selected location. The outcome of this research showed that the VEMAP data can be used for crop model applications. However, further research is needed to assess the accuracy of the datasets for a variety of crops at a regional or national scale. 相似文献
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依兰航电枢纽的建设,不仅改善了当地乃至松花江流域的航运条件、旅游环境,而且促进了松花江航道及区域经济可持续发展.同时,项目的建设也产生了一些环境问题.施工期作业区水文条件的改变对水生生物及渔业资源造成了影响.营运期库区水域生态环境的改变,使得浮游生物和底栖生物种类发生变化,鱼类组成将由复杂变为简单.因此,本文提出适宜的... 相似文献
809.
This paper examines the relationship between quality of life indicators and the gross value of minerals production from Australian regions. We used quality of life indicators, aggregated for 71 local government areas containing mining activities, of household income, housing affordability, access to communication services, educational attainment, life expectancy, and unemployment. We find no evidence of systematic negative associations between quality of life and the gross value of minerals production. Instead, mining activity has a positive impact on incomes, housing affordability, communication access, education and employment across regional and remote Australia. Whilst we do not establish causality between mining activity and quality of life, our analysis prompts a rethink of the resource curse as it applies within a single country. We did not find evidence of a resource curse, at the local government level, in Australia’s mining regions. Nevertheless, we note observations by many other researchers of negative social impacts on specific demographic sectors, localities, families of fly-in fly-out mining operations, and individuals. This contrast may be a scale issue, with the regional benefits of mineral wealth masking highly localised inequalities and disadvantage. We suggest that there is a need to better understand these impacts and, more importantly, the types of policy mechanisms government and industry can adopt to mitigate or avoid them. 相似文献
810.
Stefan Giljum Eva BurgerFriedrich Hinterberger Stephan LutterMartin Bruckner 《Resources, Conservation and Recycling》2011,55(3):300-308
Many of today's most urgent environmental problems arise from increasing volumes of worldwide production and consumption and the associated use of natural resources, including renewable and non-renewable raw materials, energy, water and land. Solid indicators to measure different dimensions of anthropogenic resource use are essential for designing appropriate policy measures for a sustainable management of these resources. Based on a brief review of the current state of the art of resource use indicators, this paper suggests a new set of complementary resource use indicators, combining existing measures for resource use. The suggested indicator set covers the core resource input categories of materials, water and land area and includes the output category of greenhouse gas emissions. This set can be applied consistently from the micro level of products and companies up to the macro level of countries and world regions. All suggested indicators take a life-cycle wide perspective on production and consumption activities. This set of indicators deals with the issue of the overall scale of the human production and consumption system. It can be regarded as the general indicator framework, based on which more specific indicators, for example, on different environmental impacts related to natural resource use, can be calculated. 相似文献