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171.
The Brazilian shift from a primarily rural to a more urban society has created major challenges that public policies must address. One of the most relevant challenges is deep social exclusion in urban areas, especially in terms of adequate housing and access to urban opportunities (e.g., jobs, housing, and services). In this context, land use and transport planning play a critical role in the sustainable development agenda. The work presented here analyses the accessibility of low‐income dwellings licenced under the Brazilian housing programme to the low‐income population. To evaluate the accessibility of the programme's target population, a case study was conducted in the city of Rio de Janeiro, where 58,000 homes licensed under the programme were analysed using GIS tools in terms of the present public transport network and the location of the homes. The amount of time it takes to access public transport on foot and the homes’ locations in relation to major urban opportunities were also analysed. Finally, the same analysis was performed for the future transport network, and the results of the two analyses were compared to identify the scope of the legacy generated by investments in preparation for the 2016 network.  相似文献   
172.
《Ambio》2021,50(12):2286
Exploitation of natural forests forms expanding frontiers. Simultaneously, protected area frontiers aim at maintaining functional habitat networks. To assess net effects of these frontiers, we examined 16 case study areas on five continents. We (1) mapped protected area instruments, (2) assessed their effectiveness, (3) mapped policy implementation tools, and (4) effects on protected areas originating from their surroundings. Results are given as follows: (1) conservation instruments covered 3–77%, (2) effectiveness of habitat networks depended on representativeness, habitat quality, functional connectivity, resource extraction in protected areas, time for landscape restoration, “paper parks”, “fortress conservation”, and data access, (3) regulatory policy instruments dominated over economic and informational, (4) negative matrix effects dominated over positive ones (protective forests, buffer zones, inaccessibility), which were restricted to former USSR and Costa Rica. Despite evidence-based knowledge about conservation targets, the importance of spatial segregation of conservation and use, and traditional knowledge, the trajectories for biodiversity conservation were generally negative.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-021-01628-5.  相似文献   
173.
Utilization of natural resources has multiplied globally, resulting in serious environmental deterioration and impeding the achievement of the Sustainable Development Goals (SDGs). For the harmonious development of human nourishment and the balance of nature, it is vital to evaluate environmental segments' resource usage, transformation, and residue, referred to as ‘footprint,’ in order to highlight carrying capacity and sustainability. This analysis highlights the Environmental Footprint (EF) of India per state from 2010 to 2020 in terms of hectares per capita. This study evaluates India's biological, hydrological, energy, ecological, and pollution footprints, carrying capacity, environmental pressure, and environmental deficit using 17 distinct parameters categorized under the themes of biological resource, hydrological resource, energy resource, and pollution concentration. We proposed a reoriented methodology and EF concepts that determine India's footprint, carrying capacity, nature of sustainability, environmental pressure index, and its consequential links to the 2030 SDGs. As a result, the biological resources contributed to ~50% of the environmental footprint, while hydrological, energy, and pollutants made up the remaining. Between 2010 and 2020, Delhi, Uttar Pradesh, Bihar, and West Bengal had the highest EF, while Jammu and Kashmir and the north-eastern provinces had the lowest. During the research period, the ecological deficit in India has increased overall. India impedes the 2030 SDGs; therefore, the study provides a picture of resource consumption, waste generation, economic growth, and societal changes, enabling academics and policymakers to redefine or document policy for a more sustainable future.  相似文献   
174.
In the turmoil of a rapidly changing economy the Albanian government needs accurate and timely information for management of their natural resources and formulation of land-use policies. The transformation of the forestry sector has required major changes in the legal, regulatory and management framework. The World Bank financed Albanian National Forest Inventory project provides an analysis of spatially explicit land-cover/use change dynamics in the period 1991–2001 using the FAO/UNEP Land Cover Classification System for codification of classes, satellite remote sensing and field survey for data collection and elements of the object-oriented geo-database approach to handle changes as an evolution of land-cover/use objects, i.e. polygons, over time to facilitate change dynamics analysis.Analysis results at national level show the trend of natural resources depletion in the form of modifications and conversions that lead to a gradual shift from land-cover/use types with a tree cover to less dense tree covers or even a complete removal of trees. Policy failure (e.g., corruption, lack of law enforcement) is seen as the underlying cause. Another major trend is urbanisation of areas near large urban centres that change urban-rural linkages. Furthermore, after privatisation agricultural areas increased in the hills where environmental effects may be detrimental, while prime agricultural land in the plains is lost to urbanisation.At district level, the local variability of spatially explicit land-cover/use changes shows different types of natural resources depletion. The distribution of changes indicates a regional prevalence, thus a decentralised approach to the natural resources management could be advocated.  相似文献   
175.
电子废弃物已成为城市环境的新压力。本文从加强立法、生产者负责制以及建立健康绿色的废旧电子回收体系三方面分析电子废物变废为宝的绿色途径,从而推动电子废物资源化、无害化发展。  相似文献   
176.
CO_2 Emissions Embodied in China-U.S.Trade   总被引:1,自引:0,他引:1  
After the Kyoto Protocol was implemented, carbon leakage exerts great influences on international trade and economy. Trade creates a mechanism for consumers to shift environmental pollution associated with their consumption to other countries. China has overtaken the U.S. as the world's biggest CO2 emitter since 2006. As China's second largest trade partner, the U.S. has the biggest trade deficit with China which has aroused a lot of disputes between the two parties. But so far the assessments of the trade imbalance of China-U.S. have paid little attention to environmental impacts associated with the trade imbalance. Applied an input-output approach, the article estimates the amount of CO2 embodied in China-U.S. trade during 1997-2007. It was found that through trade with China, the U.S. reduced its CO2 emissions compared with a non-trade scenario. Due to the greater carbon-intensity and relatively less efficient production processes of Chinese industry, China-U.S. trade resulted in more CO2 emissions in China and the world. In the end, the article gives some suggestions: it is equal and sustainable that the international accounting methodologies should be improved, for CO2 emissions responsibility must be designed to account for the dynamic nature of international trade.  相似文献   
177.
This study uses California data to compare redevelopment for properties subject to mandatory and voluntary cleanup. CalSites are subject to the CERCLA liability approach, while properties in the Voluntary Cleanup Program (VCP) are subject to a risk-based approach (RBA) that allows some contamination to remain for non-residential redevelopment. The expectation is that VCPs will show a greater proportion of industrial redevelopment, which has the least stringent standard, and a smaller proportion of residential redevelopment. The results show an overall trend toward more residential redevelopment of contaminated properties, but consistent with expectations, the trend is weaker for VCP properties than CalSites.  相似文献   
178.
根据设备设施、工艺流程、危险物质的特点,将中国运载火箭技术研究院危险点分为起重机械、机械设备、变配电站(室)、锅炉、压力容器、危化品等6类。以该分类为基础,选用风险评价半定量的评点法作为危险点评价分级的理论依据。分析并研究各类危险点所应考虑的不同评点因素,设计评点分层标准和评点分值,计算各类危险点的总评点分值。结合研究院危险点安全管理的控制重点,统筹分析每类危险点的风险等级分布情况,确定其等级划分标准。  相似文献   
179.
一种新的结构可靠度通用计算方法   总被引:1,自引:0,他引:1  
根据可靠度指标β的几何定义,运用具有全局优化能力的改进遗传算法,提出一种新的结构可靠度通用计算方法。针对可靠度几何优化模型搜索区域大而可行区域小的特点,在可靠区域和失效区域分别产生初始种群,在两种群之间通过不断迭代的二分法,使二分点不断接近极限状态曲面(线),从而产生可行解。对可行解进行选择、交叉、变异,最后求出全局最优解。该方法不需要使用结构功能函数的偏导数,对于功能函数不能明确表达的可靠度问题尤为适用;对于功能函数可以明确表达但求导复杂的问题,可省去求导过程;可任意设定初始值,且不受结构功能函数凹凸性的限制;通过算例验证,所提方法具有较高的精度和效率。  相似文献   
180.
Field experiment on 10 ha area of fly ash dump was conducted to restore and revegetate it using biological interventions, which involves use of organic amendment, selection of suitable plant species along with specialized nitrogen fixing strains of biofertilizer. The results of the study indicated that amendment with farm yard manure at 50 t/ha improved the physical properties of fly ash such as maximum water holding capacity from 40.0 to 62.42% while porosity improved from 56.78 to 58.45%. The nitrogen content was increased by 4.5 times due to addition of nitrogen fixing strains of Bradyrhizobium and Azotobacter species, while phosphate content was increased by 10.0 times due to addition of VAM, which helps in phosphate immobilization. Due to biofertilizer inoculation different microbial groups such as Rhizobium, Azotobacter and VAM spores, which were practically absent in fly ash improved to 7.1 × 107, 9.2 × 107 CFU/g and 35 VAM spores/10 g of fly ash, respectively. Inoculation of biofertilizer and application of FYM helped in reducing the toxicity of heavy metals such as cadmium, copper, nickel and lead which were reduced by 25, 46, 48 and 47%, respectively, due to the increased organic matter content in the fly ash which complexes the heavy metals thereby decreasing the toxicity of metals. Amendment of fly ash with FYM and biofertilizer helped in profuse root development showing 15 times higher growth in Dendrocalamus strictus plant as compared to the control. Thus amendment and biofertilizer application provided better supportive material for anchorage and growth of the plant.  相似文献   
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