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1.
Ecosystems provide life-sustaining services upon which human civilization depends, but their degradation largely continues unabated. Spatially explicit information on ecosystem services (ES) provision is required to better guide decision making, particularly for mountain systems, which are characterized by vertical gradients and isolation with high topographic complexity, making them particularly sensitive to global change. But while spatially explicit ES quantification and valuation allows the identification of areas of abundant or limited supply of and demand for ES, the accuracy and usefulness of the information varies considerably depending on the scale and methods used. Using four case studies from mountainous regions in Europe and the U.S., we quantify information gains and losses when mapping five ES - carbon sequestration, flood regulation, agricultural production, timber harvest, and scenic beauty - at coarse and fine resolution (250 m vs. 25 m in Europe and 300 m vs. 30 m in the U.S.). We analyze the effects of scale on ES estimates and their spatial pattern and show how these effects are related to different ES, terrain structure and model properties. ES estimates differ substantially between the fine and coarse resolution analyses in all case studies and across all services. This scale effect is not equally strong for all ES. We show that spatially explicit information about non-clustered, isolated ES tends to be lost at coarse resolution and against expectation, mainly in less rugged terrain, which calls for finer resolution assessments in such contexts. The effect of terrain ruggedness is also related to model properties such as dependency on land use-land cover data. We close with recommendations for mapping ES to make the resulting maps more comparable, and suggest a four-step approach to address the issue of scale when mapping ES that can deliver information to support ES-based decision making with greater accuracy and reliability.  相似文献   

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An enormous research effort is currently being directed towards the development of efficient visible‐light‐driven photocatalysts for renewable energy applications including water splitting, CO2 reduction and alcohol photoreforming. Layered double hydroxide (LDH)‐based photocatalysts have emerged as one of the most promising candidates to replace TiO2‐based photocatalysts for these reactions, owing to their unique layered structure, compositional flexibility, controllable particle size, low manufacturing cost and ease of synthesis. By introducing defects into LDH materials through the control of their size to the nanoscale, the atomic structure, surface defect concentration, and electronic and optical characteristics of LDH materials can be strategically engineered for particular applications. Furthermore, through the use of advanced characterization techniques such as X‐ray absorption fine structure, positron annihilation spectrometry, X‐ray photoelectron spectroscopy, electron spin resonance, density‐functional theory calculations, and photocatalytic tests, structure‐activity relationships can be established and used in the rational design of high‐performance LDH‐based photocatalysts for efficient solar energy capture. LDHs thus represent a versatile platform for semiconductor photocatalyst development with application potential across the energy sector.  相似文献   

4.
Global Drivers and Tradeoffs of Three Urban Vegetation Ecosystem Services   总被引:1,自引:0,他引:1  
Our world is increasingly urbanizing which is highlighting that sustainable cities are essential for maintaining human well-being. This research is one of the first attempts to globally synthesize the effects of urbanization on ecosystem services and how these relate to governance, social development and climate. Three urban vegetation ecosystem services (carbon storage, recreation potential and habitat potential) were quantified for a selection of a hundred cities. Estimates of ecosystem services were obtained from the analysis of satellite imagery and the use of well-known carbon and structural habitat models. We found relationships between ecosystem services, social development, climate and governance, however these varied according to the service studied. Recreation potential was positively related to democracy and negatively related to population. Carbon storage was weakly related to temperature and democracy, while habitat potential was negatively related to democracy. We found that cities under 1 million inhabitants tended to have higher levels of recreation potential than larger cities and that democratic countries have higher recreation potential, especially if located in a continental climate. Carbon storage was higher in full democracies, especially in a continental climate, while habitat potential tended to be higher in authoritarian and hybrid regimes. Similar to other regional or city studies we found that the combination of environment conditions, socioeconomics, demographics and politics determines the provision of ecosystem services. Results from this study showed the existence of environmental injustice in the developing world.  相似文献   

5.
Urbanization is acknowledged as one of the most severe threats to stream health, spawning recent research efforts into methods to ameliorate these negative impacts. Attention has focused on streams in densely-populated cities but less populous regional urban centres can be equally prone to some of the same threats yet might not meet the conventional definitions of urban. Several recent reviews have identified the changes to streams that occur during urbanization but they note that few ecological studies have explored ecosystem-level responses, typically focusing instead on state variables such as invertebrate abundance. In many regional urban streams, changes to the extent of impervious drainage have implications for their hydrology and channel morphology but the influence of these changes on fundamental ecosystem processes of leaf litter breakdown and transport compared with those in nearby rural streams are poorly known. The widespread practice of planting exotic trees along riparian zones and street margins draining into urban streams further exacerbates the disruption of natural organic matter dynamics. The combination of seasonal leaf fall by exotic species and the altered drainage patterns through urbanization in Armidale, a regional town in New South Wales, Australia, resulted in contrasting patterns of benthic organic matter storage over 18 months compared to nearby reference and rural streams. Macroinvertebrate detritivore densities were low in the urban stream, implying disruption of the usual biological pathways of leaf breakdown. Understanding the interactions of hydrology, drainage pattern, leaf input and biological attributes of a stream is crucial for managers trying to restore stream ecosystem services without incurring public concern about the appearance of regional urban streams.  相似文献   

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当前生态系统服务空间性研究大多在区域或城市尺度上开展,风景园林生态实践的指导性较为有限,研究聚焦场地尺度,旨在从生态系统服务供需视角看待城市滨水空间的发展与规划设计实践。在已有生态系统服务供需方面文献爬梳的基础上,提出影响需求的三大因素及其需求类型的划分方法,甄别影响城市滨水空间生态系统服务供给能力的核心指标,选取上海苏州河市区段进行实证研究,采取田野调查法、文献研究法,并基于GIS进行需求目标与供给能力的空间制图。通过拟合分析比对创新性地提出指导城市滨水空间生态实践的三大空间智慧:1)基于需求目标研判制定发展策略的空间智慧;2)分段分类型供给满足存量更新需求的空间智慧;3)生态系统服务供需平衡转向匹配的空间智慧,为城市滨水空间的生态实践提出理论依据、评价标准及技术支撑。  相似文献   

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A ubiquitous problem for community-based regional environmental agencies is to set strategic management priorities among a myriad of issues and multiple stakeholder perspectives. Here, we quantify the strategic management priorities for natural capital and ecosystem services using multicriteria decision analysis (MCDA) in a case study of the South Australian Murray-Darling Basin Natural Resources Management Board (the Board) region. A natural capital and ecosystem services framework was tailored to present decision-makers with a range of potential issues for strategic consideration as goal hierarchies in MCDA. Priorities were elicited from the Board and its four regionally based consultative groups using the Analytical Hierarchy Process and swing weights. Centered log ratio transformed weights were analyzed using multiple pairwise ANOVA comparisons (Dunnett’s T3) and hierarchical cluster analysis. Substantial variation in priorities occurred between decision-makers. Nonetheless, analysis of priorities for assets and services robustly demonstrated that water was the highest priority, followed by land, then biota, with atmosphere the lowest priority. Decision-makers also considered that environmental management should not impact negatively on built or social capital. Few significant differences in priorities were found between decision-maker groups. However, clusters of manager types were found which represent distinct alternative management strategies, notably the prioritization of either intermediate or final ecosystem services. The results have implications for regional environmental decision-making and suggest that embracing variation in perspectives may be a better way forward for multistakeholder MCDA. The study operationalizes natural capital and ecosystem services by providing strategic priorities for targeting management and policy within the context of community-based, regional environmental management.  相似文献   

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The current flow of carbon for the production, use, and waste management of polymer‐based products is still mostly linear from the lithosphere to the atmosphere with rather low rates of material recycling. In view of a limited future supply of biomass, this article outlines the options to further develop carbon recycling (C‐REC). The focus is on carbon dioxide (CO2) capture and use for synthesis of platform chemicals to produce polymers. CO2 may be captured from exhaust gases after combustion or fermentation of waste in order to establish a C‐REC system within the technosphere. As a long‐term option, an external C‐REC system can be developed by capturing atmospheric CO2. A central role may be expected from renewable methane (or synthetic natural gas), which is increasingly being used for storage and transport of energy, but may also be used for renewable carbon supply for chemistry. The energy input for the C‐REC processes can come from wind and solar systems, in particular, power for the production of hydrogen, which is combined with CO2 to produce various hydrocarbons. Most of the technological components for the system already exist, and, first modules for renewable fuel and polymer production systems are underway in Germany. This article outlines how the system may further develop over the medium to long term, from a piggy‐back add‐on flow system toward a self‐carrying recycling system, which has the potential to provide the material and energy backbone of future societies. A critical bottleneck seems to be the capacity and costs of renewable energy supply, rather than the costs of carbon capture.  相似文献   

10.
纤维素丁醇作为一种新型可再生能源,具有与汽油配伍性好、蒸汽压较低、安全系数高、能量密度高及抗爆性好等优势,在替代化石燃料方面极具发展前景,已受到广泛关注。虽然纤维素丁醇工业化生产仍存在一定的技术瓶颈,生产技术经济性也较差,产业化发展受到限制,但未来通过政策支持,在丰富的农林剩余物资源及巨大市场需求的条件下,纤维素丁醇作为新型能源仍具有非常广阔的发展前景。为了更好地促进纤维素丁醇产业发展,以纤维素丁醇的产业化发展为研究对象,总结了纤维素丁醇产业发展现状,分析了纤维素丁醇产业发展过程中存在的问题,从政策、资源及市场等方面对未来纤维素丁醇产业发展的前景进行了预测,并对如何促进其产业化发展提出了建议。  相似文献   

11.
The New Economy of Nature: The Quest to Make Conservation Profitable , by G. C. Daily and K. Ellison  相似文献   

12.
生物制氢——能源、资源、环境与经济可持续发展策略   总被引:2,自引:0,他引:2  
人类面临能源危机、资源短缺、环境污染的严峻挑战,开发新的能源,合理利用资源并保护生态环境势在必行。氢能具有清洁、高效、可再生的特点,是未来重要的新能源物质。生物制氢技术利用可再生资源,特别是可利用工农业有机废弃物产氢,效率高,能耗低,污染少,成本低,具有巨大的发展潜力。本文简要阐述生物制氢技术及其发展状况,提出我国发展生物制氢技术,实现能源、资源、环境与经济可持续发展的政策建议。  相似文献   

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Short-rotation woody crops (SRWC) along with other woody biomass feedstocks will play a significant role in a more secure and sustainable energy future for the United States and around the world. In temperate regions, shrub willows are being developed as a SRWC because of their potential for high biomass production in short time periods, ease of vegetative propagation, broad genetic base, and ability to resprout after multiple harvests. Understanding and working with willow's biology is important for the agricultural and economic success of the system.

The energy, environmental, and economic performance of willow biomass production and conversion to electricity is evaluated using life cycle modeling methods. The net energy ratio (electricity generated/life cycle fossil fuel consumed) for willow ranges from 10 to 13 for direct firing and gasification processes. Reductions of 70 to 98 percent (compared to U.S. grid generated electricity) in greenhouse gas emissions as well as NOx, SO2, and particulate emissions are achieved.

Despite willow's multiple environmental and rural development benefits, its high cost of production has limited deployment. Costs will be lowered by significant improvements in yields and production efficiency and by valuing the system's environmental and rural development benefits. Policies like the Conservation Reserve Program (CRP), federal biomass tax credits and renewable portfolio standards will make willow cost competitive in the near term.

The avoided air pollution from the substitution of willow for conventional fossil fuel generated electricity has an estimated damage cost of $0.02 to $0.06 kWh?1. The land intensity of about 4.9 × 10?5 ha-yr/kWh is greater than other renewable energy sources. This may be considered the most significant limitation of willow, but unlike other biomass crops such as corn it can be cultivated on the millions of hectares of marginal agricultural lands, improving site conditions, soil quality and landscape diversity. A clear advantage of willow biomass compared to other renewables is that it is a stock resource whereas wind and PV are intermittent. With only 6 percent of the current U.S. energy consumption met by renewable sources the accelerated development of willow biomass and other renewable energy sources is critical to address concerns of energy security and environmental impacts associated with fossil fuels.  相似文献   


15.
The objectives of this study are to develop a scale of gender role ideology appropriate for assessing Quality of Care in family planning services for rural China. Literature review, focus-group discussions and in-depth interviews with service providers and clients from two counties in eastern and western China, as well as experts’ assessments, were used to develop a scale for family planning services. Psychometric methodologies were applied to samples of 601 service clients and 541 service providers from a survey in a district in central China to validate its internal consistency, reliability, and construct validity with realistic and strategic dimensions. This scale is found to be reliable and valid, and has prospects for application both academically and practically in the field.  相似文献   

16.
The Structure, Function, and Evolution of a Regional Industrial Ecosystem   总被引:2,自引:0,他引:2  
A framework has been developed to assess the structure, function, and evolution of a regional industrial ecosystem that integrates insights from industrial ecology and economic geography dimensions with complex systems theory. The framework highlights the multilayered landscape of natural ecosystem functions, economic transactions, policy contexts, and social interactions in which interfirm collaboration evolves. Its application to a single case study on the island of Puerto Rico revealed changes in the system's institutional context, its resource flows, and the composition of its industrial community. It illustrated that external forces and interactions among actors at multiple levels can cause permanent changes—but not necessarily system collapse—as policy choices and interfirm cooperation can be used to organize resources in ways that retain system functionality.  相似文献   

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High oil prices and global warming that accompany the use of fossil fuels are an incentive to find alternative forms of energy supply. Photosynthetic biofuel production represents one of these since for this, one uses renewable resources. Sunlight is used for the conversion of water and CO2 into biomass. Two strategies are used in parallel: plant-based production via sugar fermentation into ethanol and biodiesel production through transesterification. Both, however, exacerbate other problems, including regional nutrient balancing and the world's food supply, and suffer from the modest efficiency of photosynthesis. Maximizing the efficiency of natural and engineered photosynthesis is therefore of utmost importance. Algal photosynthesis is the system of choice for this particularly for energy applications. Complete conversion of CO2 into biomass is not necessary for this. Innovative methods of synthetic biology allow one to combine photosynthetic and fermentative metabolism via the so-called Photanol approach to form biofuel directly from Calvin cycle intermediates through use of the naturally transformable cyanobacterium Synechocystis sp. PCC 6803. Beyond providing transport energy and chemical feedstocks, photosynthesis will continue to be used for food and feed applications. Also for this application, arguments of efficiency will become more and more important as the size of the world population continues to increase. Photosynthetic cells can be used for food applications in various innovative forms, e.g., as a substitute for the fish proteins in the diet supplied to carnivorous fish or perhaps—after acid hydrolysis—as a complex, animal-free serum for growth of mammalian cells in vitro.  相似文献   

19.
Agricultural systems are expected to have higher net secondary production (NSP) than natural systems as a result of higher trophic efficiency and lower interannual variability. These differences, however, have not been quantified across regional gradients. We compiled a dataset of herbivore biomass, consumption, NSP, annual precipitation, and aboveground net primary production (ANPP) for extensive livestock farms across a wide precipitation gradient in Argentina. We compared these data with worldwide published studies of natural systems. In a double-logarithmic scale, NSP of agricultural systems increased with ANPP from semiarid to subhumid systems and decreased from subhumid to humid systems, a response that contrasted with the linear positive increase of natural systems. Compared to natural systems dominated by homeotherms, E troph (NSP:ANPP) in agricultural systems in semiarid areas was 8 times higher, due to a 2 times higher E consump (Consumption:ANPP) and a 4 times higher E prod (NSP:Consumption). In subhumid areas, E troph was 46 times higher, due to a 13.7 times higher E consump and a 3.3 times higher E prod. In humid areas, E troph was 5 times higher, due to a 2.5 times higher E consump and a 2 times higher E prod. The interannual variation of herbivore biomass, a major determinant of NSP, was 60 % lower in agricultural than in natural systems dominated by homeotherms, and was decoupled from the variability of precipitation. Agricultural systems reach higher NSP by (1) diverting a major proportion of ANPP from the detritus to the grazing chain, (2) converting more efficiently consumption into NSP, and (3) stabilizing herbivore biomass across years.  相似文献   

20.
Land use and management intensity can influence provision of ecosystem services (ES). We argue that forest/agroforestry production systems are characterized by relatively higher C:O/C:N and ES value compared to arable production systems. Field investigations on C:N/C:O and 15 ES were determined in three diverse production systems: wheat monoculture (Cwheat), a combined food and energy system (CFE) and a beech forest in Denmark. The C:N/C:O ratios were 194.1/1.68, 94.1/1.57 and 59.5/1.45 for beech forest, CFE and Cwheat, respectively. The economic value of the non-marketed ES was also highest in beech forest (US$ 1089 ha-1 yr-1) followed by CFE (US$ 800 ha-1 yr-1) and Cwheat (US$ 339 ha-1 yr-1). The combined economic value was highest in the CFE (US$ 3143 ha-1 yr-1) as compared to the Cwheat (US$ 2767 ha-1 yr-1) and beech forest (US$ 2365 ha-1 yr-1). We argue that C:N/C:O can be used as a proxy of ES, particularly for the non-marketed ES, such as regulating, supporting and cultural services. These ES play a vital role in the sustainable production of food and energy. Therefore, they should be considered in decision making and developing appropriate policy responses for land use management.  相似文献   

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