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991.
Located on the northeast Brazilian coast, Olinda is one of UNESCO’s World Heritage Sites, which is economically dependent
on tourism, commerce, industry, and the informal economy. Despite its environmental and socioeconomic importance, the city
of Olinda (understanding the coast as part of it) has suffered several environmental and human disturbances over the last
decades. This work describes the environmental and social status of Olinda’s beaches and makes recommendations concerning
the development of an Integrated Coastal Management Plan for this coastal zone of the Brazilian littoral. The methodology
adopted in this study is based on field campaigns (social, physical, chemical, and biological data collection), local observations,
and the collection of sea contention building project data from city hall. The results showed that along the seven studied
beaches, the main problems were related to the: (i) building of coastal protections, (ii) inefficient sewage disposal systems,
(iii) inefficient urban management, and (iv) natural events (equinoctial spring tides and precipitation/evaporation rates).
Casa Caiada beach showed the best hydrologic conditions as a consequence of its morphology and it presents facilities that
attract housing and recreation investments (by private and public sectors) valuing and improving local use conditions. The
obtained data showed that the studied beaches need an urgent action plan to minimize the environmental degradation of Olinda’s
littoral and to promote sustainable development of the local coastal environments. 相似文献
992.
基于苏州沿江生态城市群建设的背景和景观生态条件分析,提出了建设有江南特色的苏州沿江景观生态格局的思路,即通过以水为核心,以"一江十道、五线、廿环"生态廊道和九大斑块为主的建设,构筑以农山郊野为背景的多等级网络式的沿江景观生态格局,从而整合区域生态景观,推动苏州沿江生态城市群建设。 相似文献
993.
Roberto Mancinelli Vincenzo Di Felice Shafiqul Bari Emanuele Radicetti Enio Campiglia 《国际发展与全球生态学杂志》2018,25(1):35-46
The research was based on a comparative study of three representative rural areas (Dovras, Larissa, and Messapia) in Greece. Remote sensing data were collected (maps, aerial photographs) for the landscape analysis and elaborated using GIS linked with economic and social parameters regarding land use. By using a selected core set of landscape indicators, this research aims at providing a useful tool for assessing agroecosystem management at territorial level and hopefully assist decision-making for the promotion of sustainability. The selected tool showed that the study area of Messapia presented the highest level of environmental sustainability, while the area of Dovras showed the best combination of agricultural productivity and landscape management. Results showed that the ecoregions of Dovras, Larissa, and Messapia presented a landscape composed of important ecological function areas in the percentages of 40%, 15%, and 70%, respectively, and of cultivated areas in the percentages of 55%, 71.19%, and 19.75%, respectively. 相似文献
994.
Urban road network development (RND) plays an important role in social and economic evolution. However, the unlimited expansion of roads leads to great changes in urban landscape patterns, which further affect ecosystems. To better characterize the urban ecological risk (UER) of RND, in this study, RND was considered the stressor and habitat provision the assessment endpoint in a UER assessment. According to the theory of landscape ecology, habitat quality disturbance intensity (HQDI) is used to quantify the negative effect of RND on an urban ecosystem. In particular, we aimed to explore the exposure-response function between road density and HQDI under RND stress. A case study was carried out in Xiamen City to examine this association. In terms of spatial distribution, this study showed that developed areas had the highest HQDI values, whereas low HQDI values were mostly associated with suburban areas. In addition, the probability distribution of HQDIs was uneven and the urban ecosystem showed unequal sensitivities to different types of roads. Based on a multilevel characterization of UER, results of this provide a framework to predict UER under RND stress and may enhance the ability of risk managers to develop scientifically based control measures. 相似文献
995.
近15年来长江源区土地利用变化及其生态环境效应 总被引:14,自引:3,他引:11
潘竟虎 《长江流域资源与环境》2005,14(3):310-315
长江源区是我国重要的水源涵养区,也是高海拔地区生物多样性最集中的地区和生态变化最为敏感的地区。基于1986年TM和2000年ETM+卫星遥感数据和野外实地调查,采用GIS软件和景观生态空间分布格局分析方法,对长江源区近15年来土地利用类型的时空变化进行了研究。结果表明:1986~2000年,源区林地和湿地面积减少54.2 %和42.69 %,建设用地、耕地和未利用土地面积分别增加120 %、43.83 %和21.1 %。全区土地利用的空间位置转换面积大于其数量变化,土地利用类型总变化的面积大小依次是草地>未利用土地>湿地>水域>林地>耕地>建设用地。土地利用动态转化过程以草地转化为未利用土地、湿地转化为草地和未利用地逆转为草地为主要特征。15年里景观破碎化程度加剧,分维数和多样性指数增加,优势度降低,景观异质性增强。长江源区脆弱的生态体系对土地利用变化响应强烈,造成水土流失与沙漠化程度加剧,导致大范围高寒草甸、草原植被退化,湿地萎缩。气候变化和人类经济活动是导致研究区土地利用变化的主要因素。 相似文献
996.
The conversion of landscapes by human activities results in widespread changes in landscape spatial structure. Regardless of the type of land conversion, there appears to be a limited number of common spatial configurations that result from such land transformation processes. Some of these configurations are considered optimal or more desirable than others. Based on pattern geometry, we define ten processes responsible for pattern change: aggregation, attrition, creation, deformation, dissection, enlargement, fragmentation, perforation, shift, and shrinkage. A novelty in this contribution is the inclusion of transformation processes causing expansion of the land cover of interest. Consequently, we propose a decision tree algorithm that enables detection of these processes, based on three parameters that have to be determined before and after the transformation of the landscape: area, perimeter length, and number of patches of the focal landscape class. As an example, the decision tree algorithm is applied to determine the transformation processes of three divergent land cover change scenarios: deciduous woodland degradation in Cadiz Township (Wisconsin, USA) 1831–1950, canopy gap formation in a terra firme rain forest at the Tiputini Biodiversity Station (Amazonian Ecuador) 1997–1998, and forest regrowth in Petersham Township (Massachusetts, USA) 1830–1985. The examples signal the importance of the temporal resolution of the data, since long-term pattern conversions can be subdivided in stadia in which particular pattern components are altered by specific transformation processes. 相似文献
997.
Tran?Duc?ThanhEmail author Yoshiki?Saito Dinh?Van?Huy Van?Lap?Nguyen Thi?Kim?Oanh?Ta Masaaki?Tateishi 《Regional Environmental Change》2004,4(1):49-62
Vietnam is a tropical to subtropical country located on the eastern Asian coast where the Red (Song Hong) and Mekong rivers discharge into the sea. The catchments of these two transboundary rivers cover parts of six countries, and their water and sediment discharges greatly influence the coastal seas of Vietnam. The impact of human activities include changes in the supply and distribution of water, sediments, and nutrients; changes in the relationships and balance among dynamically interacting factors and processes; and changes in the quality of the coastal and marine environments due to the increased use and accumulation of pollutants and the loss of habitats. These impacts have resulted in increasing unpredictability and severity of coastal problems such as floods, erosion, sedimentation, and saltwater intrusion; environmental pollution; and the degradation of ecosystems, with accompanying decrease in biodiversity and fishery productivity. 相似文献
998.
Levels of elements in the surficial estuarine sediments of the Hugli River, northeast India and their environmental implications 总被引:1,自引:0,他引:1
Kumar Sarkar S Francisković-Bilinski S Bhattacharya A Saha M Bilinski H 《Environment international》2004,30(8):1089-1098
The present paper is the first document of a detailed geochemical and mineralogical study of muddy to sandy mud estuarine sediments of the Hugli River collected from five different sites along its course in the coastal areas of West Bengal, northeast India. The present work attempts to establish the status of distribution and environmental implications of 52 elements in the surficial estuarine sediments and their possible sources of derivation. The level of both metallic and non-metallic elements shows a wide range of variation all along the course of the estuary and can be attributed to their differential derivation from the source rocks and differential discharge of untreated effluents originating from industrial, agricultural, aquacultural as well as domestic sewage. The element contents, particularly the heavy metal content in the sediments, are the lowest in the upstream part of the estuary at Diamond Harbor, whereas, these are slightly higher in the intermediate stretch of the estuary at Haldia to highest in the mouth of estuary at Gangasagar. These changes indicate that the metals that are carried from upstream find their ultimate depositional sink at the delta mouth near Gangasagar, where almost all the elements showed elevated values. The majority of the elements have their highest concentrations at Canning, a site within the tidal channel network of the Hugli-Matla drainage basin away from the direct influence of the Hugli River. This site is severely contaminated with huge organic load from domestic sewage, aquaculture, intensive trawling activities and agricultural runoff. Moreover, the site suffers from heavy siltation load causing an almost moribund condition of Matla River at this point. Equi-dimensional quartzo-feldspathic mineral grains are consistent components in the siliciclastic composition of the sediments and their sizes at each station are controlled by respective hydrodynamic conditions. Various flaky minerals (mica, chlorite, hornblende) are also present but show inconsistent patterns of distribution. These flaky minerals remain in suspension for a long time and do not follow the usual law of settling of particles depending on the hydrodynamic regime prevailing in the area. Presented data will serve as a baseline against which future anthropogenic effects may be assessed. A comprehensive account of heavy metal content in sediments from different coastal regions of peninsular India has also been presented for purpose of comparison. 相似文献
999.
1000.
Philippe Deuffic Jacqueline Candau 《Journal of Agricultural and Environmental Ethics》2006,19(6):563-585
In Europe, an increasing share of public subsidies for food production is being transferred towards the production of goods and environmental services. Today, farmers hesitate between the quest for technical and economic performance, which has been the paradigm of their professional activities since the 1960s, on one hand, and taking account of the environmental concerns that have been imposed since the middle of the 80s, on the other. Is it possible for farmers to continue to work according to the paradigm of the producer of agri-food goods, and how do they react to the ecologization of their activities? In this paper, we will see the difficulties and sources of tension induced by landscape maintenance in the daily professional practice of the farmers. We will see that the professional identity of the farmers is profoundly brought into question by these changes (substitution of strictly “agricultural issues” by more general concerns such as “rural issues,” substitution of the farmer by the “ecologized” peasant...). The topic of landscape reveals social strains between farmers. It also raises the question of the legitimacy of farmers to define the sense of their activities by themselves. Finally we will see that environmental orientations do not systematically open up new prospects for all farmers; they sometimes contribute to increase the inequalities between farmers (financial support proportional to land property, marginalization of farmers who are less socially integrated...). 相似文献