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191.
To assess the ability of traditional biological recording schemes and lay citizen science approaches to gather data on species distributions and changes therein, we examined bumblebee records from the UK’s national repository (National Biodiversity Network) and from BeeWatch. The two recording approaches revealed similar relative abundances of bumblebee species but different geographical distributions. For the widespread common carder (Bombus pascuorum), traditional recording scheme data were patchy, both spatially and temporally, reflecting active record centre rather than species distribution. Lay citizen science records displayed more extensive geographic coverage, reflecting human population density, thus offering better opportunities to account for recording effort. For the rapidly spreading tree bumblebee (Bombus hypnorum), both recording approaches revealed similar distributions due to a dedicated mapping project which overcame the patchy nature of naturalist records. We recommend, where possible, complementing skilled naturalist recording with lay citizen science programmes to obtain a nation-wide capability, and stress the need for timely uploading of data to the national repository.  相似文献   
192.
The modern manufacturing organisations have been adopting both lean and sustainable manufacturing paradigms to survive in the competitive environment. Lean and sustainable strategies aim at achieving productivity improvement by streamlined processes and waste elimination. The performance of such integrated lean sustainable system has to be assessed to ensure whether the strategic objectives are in line with customer value and to identify improvement opportunities that enable and enhance the competitive advantage of an integrated lean sustainable system. This paper presents the formulation of conceptual performance evaluation model to assess lean sustainable systems. Appropriate performance indicators have been identified and adaptive neuro fuzzy inference system approach is used to evaluate lean sustainability. A case of automotive component manufacturing firm in Indian scenario is exemplified. Based on the evaluation, lean sustainability index was computed and the firm was found to be ‘Averagely Lean Sustainable’. Further improvement actions to enhance the lean sustainable performance were planned and implemented. The developed performance evaluation model is capable of effectively evaluating the lean sustainable performance of manufacturing firms and has more practical relevance.  相似文献   
193.
In the present work, struvite precipitation was provoked by the dissolved CO(2) degasification technique where precipitation occurred following the degassing of the CO(2) by atmospheric air. The impact of the airflow rate and initial solution pH on struvite precipitation were assessed. For initial solution pH<6.5, no precipitation was observed. For initial solution pH>6.5, the phosphorus removal through struvite precipitation could be improved by increasing the airflow rate up to 25 L min(-1), or by increasing the initial pH for higher airflow rates. Compared to traditional techniques of struvite precipitation such as stirring and aeration, the dissolved CO(2) degasification technique is promising since a high amount of phosphorus (approximately 78%) could be removed at relatively short experiment time.  相似文献   
194.
中国酸雨控制政策初步评估研究   总被引:1,自引:0,他引:1  
采用环境政策评估的一般模式,通过构建包括评估目标、评估标准等在内的评估框架,对我国现有酸雨控制政策进行了初步的评估。结果表明,中国酸雨控制政策体系已经初步建立,不仅促进了燃煤火电厂脱硫工程的建设,为SO2排放控制奠定了工程基础,还使单位燃煤量SO2排放量得到降低。但并没有实现排放总量的绝对降低,酸沉降范围仍有扩大趋势,发生重酸雨城市的数量也在增加。主要原因是:现有的地方政府负责的管理体制设计缺乏酸雨外部性的考虑,管理成本大;燃煤火电厂脱硫装置的运行和SO2排放量的削减缺乏有效的政策手段来保证,减排成本较高。现行的政策手段中,事前控制手段由于不具有过程控制的功能,未能有效遏制SO2的排放;总量控制和排放标准的政策对象没有明确界定,无法实现边际减排;排污收费在地方政府与企业利益高度一致的背景下,刺激减排的效果一般;脱硫电价补贴作为刺激减排的经济制度,并未直接对脱硫量进行补贴,而是对上网脱硫电量实行补贴,补贴对象针对性不强。建议实施以排污许可证制度为核心的排放控制政策体系,并将排放控制政策向过程和源头延伸;同时改革排污收费制度,使其成为规费辅助排污许可证制度的实施;建议由国家环保部直接负责酸雨控制,包括燃煤火电厂的环评审批、排污许可证的发放和实施。  相似文献   
195.
在求取襄阳中心城区重现期雨量与可抽排雨量的基础上,采用基于GIS暴雨洪涝淹没模型计算不同重现期致灾雨量的淹没水深和范围;依据城市内涝对道路的实际影响,制作城市道路内涝灾害风险区划图。结果表明,该方法能够直观表达研究区域内不同雨量阈值的内涝灾害淹没风险分布,定量评估淹没水深、淹没范围。同时给出了城市道路内涝灾害风险区划图,结合城市道路信息,准确定位高风险易涝街区,为政府部门决策提供科学依据。  相似文献   
196.
Sustainability standards and certification serve to differentiate and provide market recognition to goods produced in accordance with social and environmental good practices, typically including practices to protect biodiversity. Such standards have seen rapid growth, including in tropical agricultural commodities such as cocoa, coffee, palm oil, soybeans, and tea. Given the role of sustainability standards in influencing land use in hotspots of biodiversity, deforestation, and agricultural intensification, much could be gained from efforts to evaluate and increase the conservation payoff of these schemes. To this end, we devised a systematic approach for monitoring and evaluating the conservation impacts of agricultural sustainability standards and for using the resulting evidence to improve the effectiveness of such standards over time. The approach is oriented around a set of hypotheses and corresponding research questions about how sustainability standards are predicted to deliver conservation benefits. These questions are addressed through data from multiple sources, including basic common information from certification audits; field monitoring of environmental outcomes at a sample of certified sites; and rigorous impact assessment research based on experimental or quasi‐experimental methods. Integration of these sources can generate time‐series data that are comparable across sites and regions and provide detailed portraits of the effects of sustainability standards. To implement this approach, we propose new collaborations between the conservation research community and the sustainability standards community to develop common indicators and monitoring protocols, foster data sharing and synthesis, and link research and practice more effectively. As the role of sustainability standards in tropical land‐use governance continues to evolve, robust evidence on the factors contributing to effectiveness can help to ensure that such standards are designed and implemented to maximize benefits for biodiversity conservation.  相似文献   
197.
To examine the state of pollution of Bizerte Lagoon which is exposed to intense anthropogenic pressure, two sediment cores were taken at two sites, one undergoes the dual effects of both marine waters arriving from the Mediterranean Sea through the Channel, and also of freshwater from the Tinja River; the other core is located at the center of the lagoon where water depth is maximal (12 m). Heavy metal concentrations in the two cores were assessed, with calculated enrichment factors and geo-accumulation indexes. Core sediments were also studied for chemical speciation and their monosulfide contents were measured. Results from enrichment factors and geo-accumulation indexes show an accumulation of Cd, Zn, Cr, and Pb, while chemical speciation revealed a risk only from Cd and Mn. Comparison of sequential extraction values with those of acid volatile sulfides revealed that non-toxic effects may be caused by any of the studied metals in the sediment.  相似文献   
198.
199.
鄱阳湖区国土资源综合评价和开发整治战略   总被引:1,自引:1,他引:1  
张本 《自然资源学报》1988,3(3):215-225
本文在鄱阳湖区国土资源综合评价的基础上,提出了开发整治的战略。鄱阳湖区自然资源比较丰富,开发潜力大。但是,由于洪涝干旱等自然灾害比较频繁,经济结构不合理,商品生产不发达,人口增长率高,科技文化比较落后,环境恶化等原因,影响了湖区经济的发展。为了开发整治鄱阳湖区,本文提出了整治洪涝灾害,充分发挥湖泊水资源优势;优化经济和产业结构,合理利用国土资源,充分发挥湖区农业优势;严格控制人口增长,增加智力投资,提高人口素质,促进科技进步等战略问题。  相似文献   
200.
城市道路交通噪声评价方法研究进展   总被引:24,自引:0,他引:24  
在分析城市道路交通噪声现状的主要危害的基础上,较全面介绍了国内外城市道路交通噪声评价方法的最新进展。继而分析了评价方面存在的问题,并讨论了这一环境声学领域未来发展方向。  相似文献   
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