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1.
能源植物开发利用是应对能源问题和全球变化的有效途径之一,准确的资源潜力及时空分布信息是资源规划和相关科学研究的重要基础。本文提出了耦合地理信息系统(GIS)空间分析与生命周期分析(LCA)进行能源植物开发利用潜力评估的技术方法,以黄连木为例进行研究。基于土地利用数据、遥感数据、气象数据、土壤数据,以及黄连木的生态习性,采用多因子综合评价方法,建立了1km空间栅格数据的黄连木种植适宜性综合评价模型,获取了适宜于黄连木规模化种植的土地资源与空间分布;另外,采用LCA方法对黄连木开发利用主要环节的温室气体排放进行了定量估算。结果表明,我国可用于发展黄连木的边际土地总量为1989.76万hm2,其中,适宜黄连木生长的土地面积为710.32万hm2,较适宜黄连木生长的土地面积为1279.44万hm2,总温室气体减排潜力为2544.46万t。同时,较之于传统的区域总体统计值的结果,空间栅格的评估方法可为科学决策提供更为精细的数据支撑。  相似文献   
2.
Fisheries management needs to broaden its perspective to achieve sustainable resource use. Life cycle assessment (LCA) is an ISO standardized method to evaluate the environmental impacts of products using a broad and systematic approach. In this study, the outcome of a management regime promoting species-selective trawling in Swedish Nephrops trawl fisheries was studied using LCA methodology by quantifying the impacts per kilogram of landing using two different fishing methods. Demersal trawling has previously been found to be both energy intensive and destructive in terms of seafloor impact and discards. It is demonstrated that species-selective trawling fulfils management objectives, although with tradeoffs in terms of fuel consumption and associated GHG emissions. To prioritize between impacts, one must be aware of and quantify these potential tradeoffs. LCA could be an important tool for defining sustainable seafood production as it can visualize a broad range of impacts and facilitate integrated, transparent decision making in the seafood industry. It is also concluded that, with current LCA methodology, use of total discarded mass could increasingly be distinguished from potential impact by applying two new concepts: primary production requirements and threatened species affected.  相似文献   
3.
The effluents of wastewater treatment plants in small sized communities of less than 2000 population equivalent (PE), which are discharged into sensitive receiving water environments, must receive “appropriate treatment” according to the EU Urban Wastewater Treatment Directive. Appropriate treatment depends on the quality objectives of the receiving waters as well as the relevant provisions of the member states. In this study, wastewater treatment options, such as vegetated land treatment (VLT), constructed wetlands (CW), and activated sludge treatment (AST), by which effluents are discharged to sensitive and less sensitive areas are evaluated by the life cycle assessment (LCA) approach. For this purpose, data related to energy usage, land requirement, raw material consumption, and released emissions from the life phases were collected with an inventory study and the environmental impacts were assessed by using SimaPro 7.1 LCA software. The results obtained from the assessments were compared with each other, which indicated that for small‐scale communities VLT and CW are the most environmentally friendly wastewater treatment option.  相似文献   
4.
煤矸石中潜在有害微量元素析出过程探讨   总被引:1,自引:0,他引:1  
引入LCA(生命周期评价法)中产品"生命周期"的概念,系统地对煤炭开采的副产品-煤矸石整个"生命周期"中微量元素的析出过程进行了研究.结果表明:煤矸石的整个生命周期是一个微量元素析出-富集-析出的长期过程,随着风化程度的增强,煤矸石的环境影响逐渐增大.  相似文献   
5.
根据森林旅游资源具有生命周期的特点,引入环境评价中的生命周期评价方法与步骤,并利用生命周期矩阵的半定量方法,对森林景观进行生命力评价。结果表明:(1)各个景观所表现出的生命力,在森林景观自身的功能基础上,取决于生命周期的各个阶段的旅游魅力,生命力评价指数和常绿阔叶林景观的相关性,说明了常绿阔叶林景观的旅游魅力;(2)森林景观应按照年龄结构进行合理的空间格局配置,以提高旅游吸引力;(3)提高森林景观的旅游生命力,必须调整资源类型结构,尽量扩大高质量的森林景观种类比例,优化树种结构。  相似文献   
6.
Fisheries management determines how much of each stock can be landed when, where and how fishing is permitted. It has been identified to strongly influence the environmental performance of the fishing industry, including fuel use. As fuel data for fisheries is scarce, especially on a detailed level, the aim of this study was to develop an approach for utilizing fleet-wide fuel data to estimate the fuel use of individual fisheries and mapping how fuel efficiency in Swedish fisheries is influenced by management. Swedish demersal trawl fisheries were studied between 2002 and 2010. Results show that the overall fuel efficiency has improved and interesting patterns between different fisheries and vessel sizes emerged. The difference in fuel efficiency per kilo landing between large and small trawlers was generally small, unless catch capacity was lowered e.g. by selective grids. Stock rebuilding was shown to be highly important for fuel efficiency, as fuel use was inversely correlated to the biomass of eastern Baltic cod. However, rebuilding can also lead to trade-offs e.g. in the case of selective trawling, where protection of depleted stocks comes at the cost of higher fuel intensity per landing. Finally, tax exemption of fuel use in fisheries was shown to maintain inefficient fisheries. These results could be used to reduce overall environmental impacts of fishing further by incorporating fuel use as an additional aspect into the fisheries management system.  相似文献   
7.
Attributional LCA, which monitors specific production systems in steady state conditions, is increasingly used in fisheries to assess the environmental profile of fleets and seafood supply chains. However, this approach is not pertinent to assess the environmental consequences of (large scale) policies. In contrast, consequential LCA (CLCA) has been successfully implemented in other sectors to assess the expected changes in environmental impacts of a given production system and other (marginal) production systems that may be affected in response to changes driven by policy or strategic decisions. CLCA commonly combines LCA with economic models to simulate the interactions occurring between the analysed systems. However, the use of these models may not be the most appropriate approach to follow for fisheries. Hence, it seems feasible that CLCA should be combined with stock prediction tools rather than with economic models, to determine how changes in stock sizes and quota restrictions may cause variations in the environmental impact of fishing fleets.  相似文献   
8.
出于能源安全的考虑及对温室气体减排的关注,世界各国近些年大力发展生物液体燃料,我国政府提倡以木薯等非粮作物为原料生产燃料乙醇。但一直以来科学家们对生物液体燃料的碳效应争论激烈,争论的焦点在于原料种植对土壤碳库的影响及不同技术条件下副产品利用的评估。本文通过建立碳平衡分析模型,将原料种植对土壤碳库影响及副产品利用的替代效应纳入研究体系,评估了我国木薯燃料乙醇生命周期内的碳排放,研究结果显示:我国每生产单位质量(1kg)木薯燃料乙醇,在新旧两种技术条件下的碳排放分别为0.457kg和0.647kg。碳排放主要来自于氮肥的使用、木薯种植对土壤碳库的破坏及木薯燃料乙醇加工转化过程能源投入,在新技术条件下分别占总排放量的9%、29%和50%。以汽油的碳排放为参照,在旧技术条件下我国木薯燃料乙醇碳排放呈现负效益,在新技术条件下其碳排放为汽油的90%,倘若能避免对土壤碳库的破坏,则这一比例将下降到64%。因此,为了促进我国木薯燃料乙醇的发展,首先应该引导农民合理施肥,利用边际土地种植木薯,不转换林地、草地等土地类型的利用方式;此外,要开发高效节能的燃料乙醇转化技术及加强对副产品的二次利用。  相似文献   
9.
Landscape is a product of interactions between human and nature that bring multiple characteristics to discrete geographic settings. Landscape character assessment (LCA) is a process of describing, mapping and evaluating distinct characters in the landscape. The aim of this study is to integrate objective and subjective assessment in landscape classification in the case of Side district in Antalya, Turkey. The methodology of the study is based on a holistic approach to combine map-based biophysical information and on-site visual landscape characteristics into the LCA process. Principal component and cluster analysis were used to understand relationships and spatial patterns between 29 landscape character areas and types which were previously defined by previous work. The main source of data was landscape characters, and 35 character attributes was processed as variables. Cluster analysis showed that landscape character areas and types in Side were gathered into two main cluster groups and five sub clusters. The majority of landscape character areas tended to constitute separate subclusters, while character types appeared to form large groups of clusters in which recognisable land-use patterns were the main activity. According to the cluster dendrogram, it was possible to interpret spatial linkages between the clusters of character areas and types and to delineate geographic classification of the main landscapes in Side. Scaling relations for LCA in a pattern-process-product framework provided an explicit understanding of the data layers in landscape classification and where the clustering can function. Biophysical characteristics comprised the pattern of the landscape, while visual characteristics demonstrated the condition of the landscape as a product. The process depends upon transformation between the objective and the subjective as a link between pattern and product. Further steps would be to conduct semistructured surveys to assess local perceptions and preferences about landscape characters for landscape quality objectives.  相似文献   
10.
围填海是区域社会经济发展到一定阶段向海洋谋求发展空间的一种基本手段。珠江三角洲是我国社会经济发展的热点区域之一,探索其近岸河口区域围填海时空过程并对其未来趋势进行分析对海岸带综合开发具有重要的意义。本研究以多源陆地资源卫星Landsat为数据源,通过影像数据处理分析探讨了珠江口围填海历史变迁过程,并对其围填海生命周期进行了估计。结果表明,珠江口围填海主要发生在改革开放后,其中1978—1988年围填海面积为18 572hm2,1988—1996年间围填海面积为25 528hm2,1996—2005年间围填海面积为13 911hm2,2005—2015年间围填海面积6 723hm2。截至2015年,珠江口共围填海面积64 753hm2,空间上主要集中分布于西部岸段。基于历史围填海时空演变过程,通过围填海生命周期图进一步对珠江口未来的围填海工程实施潜力进行形式预判。结果显示,珠海岸段和深圳前海岸段是珠江口今后实施围填海热点区域,其他区域围填海速度会相对减缓,但随着珠江口海岛逐渐与陆地海岸带相接,该区域围填海过程也将会终止。围填海生命周期分析可为海岸带实施围填海工程规划提供相关决策依据。  相似文献   
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