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本文介绍了环保产业、生态产业与绿色产业的概念和相互关系及政策意义。绿色产业突出了区域性和包容性特征、生态产业突出了循环性和节约性特征、环保产业突出了服务性特征。 相似文献
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常规的无人机地面微动特征视觉识别可靠性分析方法因无人机航向重叠度较低,导致可靠性分析方法存在较高的相对误差。为此,设计无人机地面微动特征视觉识别的可靠性分析方法。通过分析无人机视觉定位和地面微动特征识别过程,确定与之对应的可靠性影响因子,利用影响因子分别计算无人机视觉定位可靠性指数和地面微动特征识别可靠性指数,以两者的和的大小作为依据,判断可靠性的强弱,完成可靠性分析。实验结果表明,与常规的可靠性分析方法相比,设计的无人机地面微动特征视觉识别的可靠性分析方法相对误差得到了降低,保持在正常范围内,证明了该方法更适合应用在无人机地面微动特征视觉识别中。 相似文献
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为研究沈阳地区大气气溶胶光学特性及分布特征,分析了2019年沈阳地区激光雷达组网监测的气溶胶光学厚度(AOD)季节变化特点,探讨了不同空气质量下AOD分布特征及与颗粒物浓度、气象因素间的关系.结果表明,沈阳地区各雷达点位AOD季节特征存在差异性,从空间分布看,市区中心AOD相对较高.在冬季重度及以上污染天中,AOD大于... 相似文献
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通过分析老鹰岩滑坡的地质环境特征和形态特征,揭示其形成机制和产生的危害,最后根据该区地质灾害特点,提出了灾后恢复重建的相关建议。 相似文献
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基于梁子湖自然保护区1987年和2004年Landsat-TM影像遥感数据,在Erdas Imagine 8.5图像处理软件的支持下,结合野外实地考察,获得了土地利用现状图,通过对数据的统计分析,研究了保护区近20年来土地利用/土地覆盖的动态变化。研究表明:耕地和水域是保护区内的主要土地利用类型;近20年来,耕地、园地、林地、草地的面积都有减少,其中耕地面积减少了2320.816hm^2,减少比例达到11.78%,是面积减少最多的土地利用类型;居民点、交通、水域用地有所增加,其中池塘面积变化最大,增幅达到213.4%,是面积增加最多的土地利用类型,居民点用地增加了551.18hm^2,增幅达到59.07%,是增长幅度较大的土地利用类型。变化的原因主要是经济的发展、人口数量的增长和旅游业的发展。 相似文献
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Pérez-Hugalde C Romero-Calcerrada R Delgado-Pérez P Novillo CJ 《Journal of environmental management》2011,92(4):1128-1137
This work analyses land cover changes occurring between 1990 and 2000 within a Natural Protected Area, southwest of Madrid (Spain). We develop a new methodology that considers the net change in different land cover categories in each municipality of the study area. Our methodology, which uses Factorial Correspondence Analysis, allows identification of the most important changes at the municipality level and groups the municipalities where land use dynamics are similar. This method is a powerful tool for synthesis and can potentially be applied to non-spatial geographical data sources (e.g. agrarian census statistics). Our results show that the land cover around SW Madrid is highly dynamic. The shrub vegetation, arable land, heterogeneous agricultural and human-created area categories show the highest total change. The dynamics of the changes detected are dominated by decreases in the area of different types of crops and increases in forest areas. These changes may have indirect effects on the conservation of natural resources and wildlife if not managed appropriately. 相似文献
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A better public perception and knowledge on land degradation increases the individual and collective responsibility in land use and land management. Based on interviews, this paper presents results of evaluation of public perception and attitude towards degrading phenomena in the central part of Romania, an area prone to geomorphologic processes, with different land uses and a high proportion of degraded land. The research reveals natural causes, improper land use, categories of land owned, socio-economic causes and involvement of institutions as key aspects of public perception. Our research could be useful in the identification and design of measures in regional planning to attract population in prevention, mitigation and rehabilitation actions on degraded land. 相似文献
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Recent wetland area trends were estimated from the National Resources Inventory (NRI) for nonfederal rural lands for the period
1982–1987. NRI-based estimates of wetland area for states comprising the conterminous United States were highly correlated
with estimates made by the US Fish and Wildlife Service and with estimates of coastal salt marsh wetlands made by the National
Oceanic and Atmospheric Administration. Net wetland area declined by 1.1% (≈363,200 ha) during the five-year study period.
Conversion to open water, primarily caused by natural flooding in western inland basins, was responsible for altering extensive
wetland areas (≈171,400 ha). Of the human-induced wetland conversions, urban and built-up land was responsible for 48% of
the wetland loss, while agricultural development was indicated in 37% of the converted wetland area. A decrease in rural land,
and increases in both population, and urban and built-up land were associated with wetland loss among states. Potential reasons
for wetland loss were different in 20 coastal states than in 28 inland states. Proportionately, wetland loss due to development
was three times greater in coastal states than inland states, while agriculturally induced wetland losses were similar in
both groups. The proportionate declines of forested vs nonforested wetlands were not significantly different among states. 相似文献
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ABSTRACT: We analyzed data from riffle and snag habitats for 39 small cold water streams with different levels of watershed urbanization in Wisconsin and Minnesota to evaluate the influences of urban land use and instream habitat on macroinvertebrate communities. Multivariate analysis indicated that stream temperature and amount of urban land use in the watersheds were the most influential factors determining macroinvertebrate assemblages. The amount of watershed urbanization was nonlinearly and negatively correlated with percentages of Ephemeroptera‐Plecoptera‐Trichoptera (EPT) abundance, EPT taxa, filterers, and scrapers and positively correlated with Hilsenhoff biotic index. High quality macroinvertebrate index values were possible if effective imperviousness was less than 7 percent of the watershed area. Beyond this level of imperviousness, index values tended to be consistently poor. Land uses in the riparian area were equal or more influential relative to land use elsewhere in the watershed, although riparian area consisted of only a small portion of the entire watershed area. Our study implies that it is extremely important to restrict watershed impervious land use and protect stream riparian areas for reducing human degradation on stream quality in low level urbanizing watersheds. Stream temperature may be one of the major factors through which human activities degrade cold‐water streams, and management efforts that can maintain a natural thermal regime will help preserve stream quality. 相似文献
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Exploring changes in Ecuadorian land use for food production and their effects on natural resources 总被引:1,自引:0,他引:1
A model is used for the dynamic and spatially explicit exploration of near future agricultural land-use changes. In a case study for Ecuador, different plausible scenarios are formulated, taking into account possible developments in national food demand until the year 2010. The protection of nature parks and restrictions due to land degradation are evaluated with respect to their possible spatial impacts on the land-use change dynamics within the country. Under the assumptions of the demand scenarios, agricultural land-use expands significantly, resulting in more use of land in existing agricultural areas and frontier-type expansion into relatively undisturbed natural areas. The patterns of change depend on the increase in demand, competition between land-use types, changes in driving factors of land use, and the area and characteristics of land that is excluded from agricultural use. The modelled land-use dynamics are related to their possible impacts on the natural resource base, specifically soil fertility. The results indicate potential negative effects of land-use changes on the soil nutrient balance and biodiversity. It is argued that spatial and temporal quantification of land-use dynamics at the landscape level can support research and policies aimed at understanding the driving factors of land-use change and the behaviour of complex agro-ecosystems under changing conditions at different scales. In this way, issues dealing with sustainable food production and the management of the natural resource base can be addressed in a more integrated and quantitative manner. 相似文献
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Smith PG 《Environmental management》2007,39(3):338-352
Characteristics of urban natural areas and surrounding landscapes were identified that best explain winter bird use for 28
urban natural areas in southern Ontario, Canada. The research confirms for winter birds the importance of area (size) and
natural vegetation, rather than managed, horticultural parkland, within urban natural areas as well as percent urban land
use and natural habitat in surrounding landscapes. Alien bird density and percent ground feeding species increased with percent
surrounding urban land use. Higher percent forest cover was associated with higher percentages of forest, bark feeding, small
(<20 g) and insectivorous species. Natural area size (ha) was related to higher species richness, lower evenness and higher
percentages of insectivorous, forest interior, area-sensitive, upper canopy, bark feeding, and non-resident species. Higher
number of habitat types within natural areas and percent natural habitat in surrounding landscapes were also associated with
higher species richness. Common, resident bird species dominated small areas (<6.5 ha), while less common non-residents increased
with area, indicative of a nested distribution. Areas at least 6.5 ha and more generally >20 ha start to support some area-sensitive
species. Areas similar to rural forests had >25% insectivores, >25% forest interior species, >25% small species, and <5% alien
species. Indicator species separated urban natural areas from rural habitats and ordination placed urban natural areas along
a gradient between urban development and undisturbed, rural forests. More attention is needed on issues of winter bird conservation
in urban landscapes. 相似文献
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Sustainability of ground water quality considering land use changes and public health risks 总被引:2,自引:0,他引:2
One of the major environmental issues of concern to policy-makers is the increased vulnerability of ground water quality (GWQ). Another issue of equal interest is the sustainability of natural resources for future generations. To understand the sustainability of the natural resources such as water in general, one needs to understand the impact of future land use changes on the natural resources. This work proposes a methodology to address sustainability of GWQ considering land use changes, aquifer vulnerability to multiple contaminants, and public health risks. The methodology was demonstrated for the Sumas-Blaine aquifer in Washington State. The land transformation model predicted that nearly 60 percent of the land use practices would change in the Sumas-Blaine Aquifer by the year 2015. The accuracy of the LTM model predictions increased to greater levels as the spatial resolution was decreased. Aquifer vulnerability analysis was performed for major contaminants using the binary logistic regression (LR) method. The LR model, along with the predicted future land use, was used to estimate the future GWQ using two indices-carcinogenic and non-carcinogenic ground water qualities. Sustainability of GWQ was then analyzed using the concept of 'strong' sustainability. The sustainability map of GWQ showed improvements in many areas where urbanization is expected to occur. The positive impact of urbanization on GWQ is an indication of the extensive damage caused by existing agricultural activities in the study area. 相似文献
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The Jianghan Plain and the Dongting lake area, located in the middle reaches of the Yangtze River are famous for their abundant freshwater lakes. The lakes have undergone changes in size and number over thousands of years due to natural causes and human activities. The 20th century particularly, witnessed dramatic changes in the freshwater resources of this region. This paper traces and analyzes lake evolution in the middle reaches of the Yangtze River over the past century. Lakes greater than 0.1 km(2) in size are mapped using Geographic Information System. Data is acquired and integrated from drainage network maps, relief maps, historical maps and remotely sensed images for different time periods. The results indicate that while there has been little change in the number of lakes over the past century, the lake area has experienced a dramatic decrease of 58.06%. The paper also examines the natural processes and human activities that may have contributed to the decrease in lake area. The results show that the decrease in total lake area appears to coincide with periods of rapid land reclamation in the middle reaches of the Yangtze River. Moreover, uncontrolled land reclamation activities can create an increase in sediment deposition in lakes thereby further reducing the lake size. Reduction of the lake area directly affects flood-control and has a negative ecological impact on the environment and on human life and property. 相似文献