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881.
中国已经步入"互联网+"时代,再生资源行业也不例外。针对再生资源回收和电子商务的特点,借鉴国内相关成功案例,结合苏州市再生资源回收体系的现状,可以在苏州建设网络平台开展再生资源线上线下交易,并进一步对平台的流程、模块和一些重要问题进行了设计和分析。  相似文献   
882.
Dialogue about complex science and society issues is important for contemporary conservation agendas. Conferences provide an appropriate space for such dialogue, but despite its recognized worth, best practices for facilitating active dialogue are still being explored. Face‐to‐face (FTF) and computer‐mediated communication (CMC) are two approaches to facilitating dialogue that have different strengths. We assessed the use of these approaches to create dialogue on cultural perspectives of conservation and biodiversity at a national ecology conference. In particular, we aimed to evaluate their potential to enhance dialogue through their integrated application. We used an interactive blog to generate CMC on participant‐sourced issues and to prime subsequent discussion in an FTF conference workshop. The quantity and quality of both CMC and FTF discussion indicated that both approaches were effective in building dialogue. Prior to the conference the blog averaged 126 views per day, and 44 different authors contributed a total of 127 comments. Twenty‐five participants subsequently participated in active FTF discussion during a 3‐h workshop. Postconference surveys confirmed that CMC had developed participants’ thinking and deepened FTF dialogue; 88% indicated specifically that CMC helped facilitate the FTF discussion. A further 83% of respondents concluded that preliminary blog discussion would be useful for facilitating dialogue at future conferences. Construcción del Diálogo sobre Problemas Complejos de Conservación en un Escenario de Conferencia  相似文献   
883.
Island populations are vulnerable to introduced pathogens, as evidenced by extinction or population decline of several endemic Hawaiian birds caused by the malaria parasite, Plasmodium relictum (order Haemosporida). We analyzed blood samples from 363 birds caught near Guantánamo Bay, Cuba, for the presence of haemosporidian infections. We characterized parasite lineages by determining nucleotide variation of the parasite's mitochondrial cyt b gene. Fifty‐nine individuals were infected, and we identified 7 lineages of haemosporidian parasites. Fifty individuals were infected by 6 Haemoproteus sp. lineages, including a newly characterized lineage of Haem. (Parahaemoproteus) sp. CUH01. Nine individuals carried the P. relictum lineage GRW4, including 5 endemic Cuban Grassquits (Tiaris canorus) and 1 migratory Cape May Warbler (Setophaga tigrina). A sequence of the merozoite surface protein gene from one Cuban Grassquit infected with GRW4 matched that of the Hawaiian haplotype Pr9. Our results indicate that resident and migratory Cuban birds are infected with a malaria lineage that has severely affected populations of several endemic Hawaiian birds. We suggest GRW4 may be associated with the lack of several bird species on Cuba that are ubiquitous elsewhere in the West Indies. From the standpoint of avian conservation in the Caribbean Basin, it will be important to determine the distribution of haemosporidian parasites, especially P. relictum GRW4, in Cuba as well as the pathogenicity of this lineage in species that occur and are absent from Cuba.  相似文献   
884.
Plastic bags, though commonly used for packaging of goods, are highly durable and non-biodegradable. Plastic bag litter serves as a negative environmental externality detrimental to animal health and natural beauty of the environment. In an effort to curtail the excessive use of plastic bags in Botswana, the government introduced a plastic levy targeted at consumers at retail points. This study uses primary data collected from 367 respondents randomly selected from six geospatially and purposively selected shopping malls to determine the consumers’ willingness to pay (WTP) for continued plastic bag usage and their willingness to accept (WTA) to shift to eco-friendly alternatives. The results of the study revealed that open dumping and burning of plastic litter are more common in Maun than in Gaborone. It also showed that there is a significant relationship between the level of education and WTP. Further, there is a significant variation in income and education in respect to environmental awareness. The government should improve its efforts of sensitizing the public about the improper disposal of plastic bags.  相似文献   
885.
为可靠测试基准镇流器的电压/电流比、功率因数,本文简要介绍了基准整流器的校准方法,对校准结果的不确定度评定进行了分析,给出了测量结果的不确定度,同时验证了该校准方法的可行性。  相似文献   
886.
Recently, the Cradle to Cradle (C2C) theory set ground in the Netherlands, propounding that environmental impact reduction can provide a positive economical impulse to stakeholders. The building industry has warmly received this approach and considers it to be a solution to the above-mentioned burden.However, if the building sector wants to implement C2C into their practice, a paradigm shift is required. Therefore, the sector must overcome the many difficulties it encounters while striving for an eco-effective built environment.Current sustainability strategies focus on reducing the negative environmental impact of buildings. The systems theory of C2C however aims at a positive impact; this could suggest that the state-of-the-art becomes inadequate when adopting C2C as a strategy for improvement.This paper reviews contemporary systems theories and analyses them in the light of C2C, focusing on closed or continuous materials cycles. The paper finalises by describing the hiatus in and correspondence between these current theories and C2C theory.From the study we found that C2C provides new features that help continue materials, energy and water cycles, just as the contemporary theories provide potentially useful additional material for C2C. Moreover, it reveals a striking difference between the state-of-the-art and C2C.  相似文献   
887.
888.
Contemporary socio-economic transformations in South Asia are creating increasingly serious water problems (scarcity, flooding, pollution) and conflicts. Conflicts over water distribution, water-derived benefits, and risks often play out along axes of social differentiation like caste, wealth, and gender. Those with least power, rights, and voice suffer lack of access, exclusion, dispossession, and further marginalisation, resulting in livelihood insecurity or increased vulnerability to risks. In this paper we propose analysing these problems as problems of justice – problems of distribution, recognition, and political participation. Drawing on wider environmental justice approaches, a specific water justice focus needs to include both the specific characteristics of water as a resource and the access, rights, and equity dimensions of its control. We argue that recognising water problems as problems of justice requires a re-politicisation of water, as mainstream approaches to water resources, water governance, and legislation tend to normalise or naturalise their – basically political – distributional assumptions and implications. An interdisciplinary approach that sees water as simultaneously natural (material) and social is important here. We illustrate these conceptual and theoretical suggestions with evidence from India.  相似文献   
889.
受引黄影响的河流沉积物细菌群落季节变化   总被引:1,自引:0,他引:1  
河流沉积物细菌群落的季节变化对碳、氮循环和水环境演化有明显的影响.然而,受调水干预的河流沉积物细菌群落季节性变化尚不明确.本文基于16S rRNA高通量测序技术,研究了中纬度地区受引黄影响的汾河上游沉积物细菌群落组成、结构和多样性的季节变化.结果表明,在引黄调水干预下受水河流细菌群落的季节性变化仍然显著.夏季温度适宜,河流沉积物细菌群落多样性较冬季高.核心菌群组成和结构随季节变化,然而丛毛单胞菌、黄杆菌、黄单胞菌和红环菌等的优势地位不随季节改变.河水水温和ORP的季节变化显著,是造成河流沉积物细菌群落季节变化的主导因子.水质较差的黄河水引入汾河后导致沉积物细菌群落多样性显著提高.引水对河流沉积物细菌群落的影响在夏季较冬季高20%左右.引黄调水对汾河沉积物细菌群落的影响大于季节变化的影响.  相似文献   
890.
引入生态系统服务概念,考察游客作为生态系统服务关键受益人对武夷山国家公园试点区可以提供的生态系统服务作何选择,并对其投资自然资本保障生态系统服务的支付意愿进行初步分析,探讨国家公园试点建设中如何优化旅游,促进保护和公益性功能实现。研究结果显示:(1)游客以文化服务为首选,主要体现在实践性强的生态旅游、较为抽象的文化体验以及较为单纯的美景欣赏三方面,在生态旅游具体需求上会出现选择间的相互竞争;(2)除了净化空气,对供给服务和其他调节服务则需求不大;(3)在免门票假设下,具有支付意愿的游客达到90%以上,然而平均支付意愿没有达到现有门票价格;(4)教育水平和职业对支付意愿的影响最为显著,并与年龄和收入等因子一起形成具有不同支付意愿上的特征人群。因此,武夷山国家公园体制试点建设中,需要积极探索协同多种文化服务供给,大力推动社会参与理念,从根本上提高受益者对生态系统的认知,从受益者需求入手推进国家公园公益性功能的实现。  相似文献   
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