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991.
Environmental planning at different levels has been called for by environmental departments in China during last years to integrate environment consideration to economic development. Based on the accomplished environmental planning practice in Xiamen China, the paper suggests a general environmental planning process with ecological function zoning as its key steps, at the same time an effective method for ecological function zoning was formulated. The case studies of Dongfu suburban town environmental planning and Xiamen eco-city conceptual planning indicate that scientifically sound results of ecological function zoning can contribute to improving not only the adaptability and acceptability of environmental planning, also the environmental management and the decision-making. The experience shows that the ecological function zoning methods should be applied according to the principles of adaptive management, resource-based and community-based, so that it can integrate science into decision-making process, avoiding both narrow-minded viewpoints of planners and natural resource use conflicts among variety of stakeholders. Problems to be resolved in the future are also pointed out in the ending part.  相似文献   
992.
This paper is concerned with the sustainable development of a self-drive tourist destination in the remote region in Northern Australia. It first compares officially used data on visitor profiles to the information collected in the survey. Differences between data collected and available secondary data imply that tourism planning should include collection of region-specific tourism information to guide and mitigate potential environmental changes. Natural landscape features are the key attraction for visitors to the region. Visitor satisfaction levels with the current state of the destination are high. However, local residents reported perceived negative impacts of tourism, in particular on amenities and the ecology of the landscape. Visitors also reported behavior that might contribute to environmental impacts. Implications of the findings, in the context of future destination planning, are discussed.  相似文献   
993.
Small-scale geographical variation in the occurrence of polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs) and polybrominated diphenyl ethers (PBDEs) was investigated using the eggs of a terrestrial residential songbird species, the great tit (Parus major). In addition, we investigated the influence of the type of sampling location on the presence of these pollutants. To achieve this, 10 different sampling locations in Flanders (Belgium) were classified into 3 groups based on the extent of urbanisation, industrialisation and agriculture. The higher variance among sampling locations for the levels and profiles of PCBs and OCPs, suggests that local contamination sources are more important for the PCBs and OCPs compared to the PBDEs. Levels of PCBs and PBDEs were significantly higher in the industrialised sampling locations compared to the other locations. Sum PCB and sum PBDE levels reached up to 6050 and 79 ng/g lipid weight, respectively. PCBs and PBDEs were highly positively correlated for all groups, suggesting similar exposure pathways and/or mechanisms of accumulation. Significantly higher levels of OCPs (sum OCPs up to 2683 ng/g lipid weight) were detected in the rural sampling locations situated in a residential area. This suggests that local historical usage of OCPs by inhabitants may be an important source of contamination in Flanders. Contamination profiles differed also among the sampling locations. The rural sampling locations had a higher contribution of lower brominated BDE congeners, whereas the industrialised locations had a higher contribution of higher brominated congeners. The differences in contamination profiles among the sampling locations are probably due to differences in exposure. In conclusion, our results showed that the characteristics of a sampling location influence both the levels and profiles of PCBs, OCPs and PBDEs.  相似文献   
994.
In order to determine the potential for sustainable regional development of the Caspian coastal zone, a study was made for the Khachmaz–Absheron zone of Azerbaijan. An evaluation was performed to assess the anthropogenic load on landscapes. Using the 8-point scale offered by Isachenko [2001, Ecological Geography of Russia, Saint Petersburg University Press, Saint Petersburg] for the indicators of agricultural, industrial, urban and integral anthropogenic loads, we did a preliminary ranking of the provinces in the Khachmaz–Absheron zone of Azerbaijan for the each indicator taken separately. Vital statistics were used as a supplementary indicator of environmental conditions in the region. By comparing the data for provinces with each other and the data on Azerbaijan average, we have classified the provinces into 4 groups according to specific combinations of the indicators. Each group of provinces has distinctive environmental conditions and features for sustainable development. The classification makes it possible to develop certain recommendations for the regional sustainable development. Measures to be implemented within the Azerbaijan State Program on Social and Economic Development of Regions are also discussed. In the Khachmaz province, production of ecologically pure products is highly recommended. Special attention should be given to the development of tourism and recreational institutions in the Khachmaz, Khizi and Devechi provinces. Recommendations for these provinces include further development of industry on the basis of modern safe technologies. The irrigation and drainage networks should be reconstructed. The reconstruction will make it possible to reduce water loss and to increase the productivity of agriculture. In the Absheron province, Baku and Sumgait cities environmental systems are overloaded, and so the works at highly polluting enterprises must be stopped, the enterprises have to be re-equipped (old filters must be changed first of all) or relocated from the area (a decrease of environmental risk should be in the focus of attention). For improving of air quality, green areas should increase. There is a need to reduce urban traffic density and to reconstruct highways. Use of old vehicles must be forbidden or restricted, and transition to environmentally friendly fuel should be supported in every way possible. It is necessary to bring the waste management system and sanitary landfills up to international standards, and to improve the water supply and sewerage systems.  相似文献   
995.
Human society consumes resources that it is not able to reproduce. Human activities are still based on “open cycles,” starting from a condition of natural environmental balance and reaching an environmental imbalance. The challenging scope of scientific and technological research towards sustainability appears clear if it is based on this analysis: to find development systems based on “closed cycles” of resources. The challenging objective of realizing closed cycles leads to a definition of sustainability that indicates the path to sustainable development, as well as stating the general principle. It also provides a key to the qualitative measurement of sustainability. This means that the sustainability level of a system can be measured by measuring its capacity to avoid the consumption of resources. Zero consumption is a necessary condition for sustainability, and brings about as a side effect the highly desired “zero-waste” result. Materials entering the proposed endless scheme pass through the process of usefulness without losing their capacity to feed the system again after being used. Thus, the concept of “consumption” itself is replaced by one of “use” when resources are inserted into closed loops capable of feeding human development. The application of the closed cycle sustainability criterion particularly displays its feasibility, and a theoretical guiding role, in the energy sector. Energy vectors such as hydrogen and electricity enable the closure of the energy resources loop by effectively approaching the objective of “zero consumption” (and the side result of “zero waste”) through already demonstrated technological solutions.  相似文献   
996.
997.
Renewable energy sources are mainly used in the electrical sector. Electricity is not a storable commodity. Hence, it is necessary to produce the requested quantity and distribute it through the system in such a way as to ensure that electricity supply and demand are always evenly balanced. This constraint is actually the main problem related to the penetration of new renewables (wind and photovoltaic power) in the context of complex energy systems. The paper analyzes some aspects in connection with the problem of new renewable energy penetration. The case of Italian scenario is considered as a meaningful reference due to the characteristic size and the complexity of the same. The various energy scenarios are evaluated with the aid of a multipurpose software taking into account the interconnections between the different energetic uses. In particular, it is shown how the penetration of new renewable energies is limited at an upper level by technological considerations and it will be more sustainable if an integration of the various energy use (thermal, mobility and electrical) field will be considered.  相似文献   
998.
This study aims to estimate the intensification of rice farming in Myanmar particularly due to chemical fertilizer application, using farm-level data obtained from field surveys conducted in the 2000s. Relatively high-input rice farming was found in dry season crop in the delta zone and the double crop in well-irrigated lowlands of the central dry zone. The chemical fertilizer used there was about 88–159 kg NPK (nitrogen, N; phosphate, P2O5; and potash, K2O) ha−1 (76–110 kg nitrogen (N) ha−1), and the average paddy yield ranged from 2.8 to 3.5 ton ha−1. On the other hand, nutrient input in survey sites of rain-fed lowland was between 11 and 53 kg NPK ha−1 (5 and 36 kg N ha−1), and the yield ranged from 1.1 to 2.3 ton ha−1. The national average of paddy yield and nutrient input of fertilizer was roughly estimated to be around 2.4 ton ha−1 and 60 kg NPK ha−1, respectively. A gap was observed between these calculated values and the official statistics. A comparison of fertilizer use efficiency for rice production in Myanmar with that in China and Vietnam has shown that the efficiency in Myanmar has not declined to an inappropriate level even in its intensive ones. Rice production in Myanmar has room for increasing the yield by capital intensification. Nevertheless, considering its sustainability as well as productivity, further intensification in rice farming technology in irrigated lowlands of Myanmar may neither be the best nor the only way.  相似文献   
999.
The Arctic is a region of the world experiencing extremely rapid climatic and social change. Indigenous communities have faced similar challenges for millennia and have historically demonstrated remarkable resilience to socioecological perturbations. In contemporary contexts, however, it appears that the pace and extent of change is overwhelming the adaptive capacities of many indigenous communities. Scholars recently completed a survey of living conditions spanning the circumpolar Arctic to quantitatively document the impacts of social and ecological stress across regions. The database they created is called the Survey of Living Conditions in the Arctic or SLiCA. This article explores the utility of using this dataset to compare livelihood systems across three sub-regions of Alaska and four sub-regions within the Chukotka Autonomous Okrug of the Russian Federation. The results point out that livelihood systems in Chukotka have a substantially lower level of sustainability than in Northwest Alaska due to the high prevalence of vulnerable households.  相似文献   
1000.
Sub-Saharan Africa has been portrayed as the most vulnerable region to the impacts of global climate change because of its reliance on agriculture which is highly sensitive to weather and climate variables such as temperature, precipitation, and light and extreme events and low capacity for adaptation. This article reviews evidence on the scope and nature of the climate change challenge; and assesses the impact of climate change on agriculture and food security in Sub-Saharan Africa. From the review, it is apparent that the climate in Africa is already exhibiting significant changes, evident by changes in average temperature, change in amount of rainfall and patterns and the prevalence of frequency and intensity of weather extremes. The review also revealed that although uncertainties exist with regards to the magnitude of impacts, climate will negatively affect agricultural production in Sub-Saharan Africa. Specifically, as result of current and expected climate change, the area suitable for agriculture, the length of growing seasons and yield potential, particularly along the margins of semi-arid and arid areas, are expected to decrease. These impacts will affect all components of food security: food availability, food accessibility, food utilisation and food stability and hence increase the risk of hunger in the region. The review thus confirms the general consensus that Sub-Saharan Africa is the most vulnerable region to climate change. It suggests that, policymakers and development agencies should focus on formulating and implementing policies and programmes that promote farm level adaptation strategies currently being practiced by farmers across the region.  相似文献   
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