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71.
72.
含硫油品储罐内的腐蚀产物与油品中的活性硫反应生成硫化物,而此类硫腐蚀产物氧化自燃是导致储油罐发生火灾、爆炸事故的重要原因.通过试验考察了氧气体积比对硫腐蚀产物氧化自燃过程的影响,探索了铁锈模拟物在氧化过程中SO2气体的释放规律.结果表明:氧气浓度越高,硫腐蚀产物的自燃危险性越大;随着O2浓度增加,氧化反应中SO2的浓度越大,SO2气体析出速度越快,当氧化反应的温度为40℃时,SO2气体浓度达到最大.  相似文献   
73.
将国内外基于投入产出模型的虚拟水研究进行系统概括,认为按研究层面可以归纳为区域之间的虚拟水贸易和产业间部门用水关联两方面,并指出:(1)目前基于投入产出分析技术的虚拟水研究基本建立在价值型投入产出模型的基础上,实际上将产业虚拟水替代了原本产品虚拟水的概念.(2)目前针对工业品、服务品的虚拟水量化研究不足,并未独立研究非农产品虚拟水量化时的差异性.最后文章提出产业生态学中近年来发展的混合生命周期评价方法(Hybrid life-cycle assessment,HLCA).  相似文献   
74.
药品和个人护理用品(Pharmaceuticals and personal care products,PPCPs)在环境中广泛存在,威胁生态环境和人类健康,受到越来越多的关注.本文综述了固体基底中PPCPs的检测方法,总结了国内外污泥、土壤、沉积物等基底中PPCPs的污染现状,并对PPCPs的进一步研究进行了展望.结果表明,PPCPs的检测方法朝多样化和趋优化的方向发展.污泥样品中PPCPs种类多、浓度高(μg·kg-1—mg·kg-1),土壤和沉积物中虽然浓度不高,但是总量不可小觑.目前,固体基底中的PPCPs还需要更全面和更广泛的研究.  相似文献   
75.
A fungal perspective on conservation biology   总被引:1,自引:0,他引:1       下载免费PDF全文
Hitherto fungi have rarely been considered in conservation biology, but this is changing as the field moves from addressing single species issues to an integrative ecosystem‐based approach. The current emphasis on biodiversity as a provider of ecosystem services throws the spotlight on the vast diversity of fungi, their crucial roles in terrestrial ecosystems, and the benefits of considering fungi in concert with animals and plants. We reviewed the role of fungi in ecosystems and composed an overview of the current state of conservation of fungi. There are 5 areas in which fungi can be readily integrated into conservation: as providers of habitats and processes important for other organisms; as indicators of desired or undesired trends in ecosystem functioning; as indicators of habitats of conservation value; as providers of powerful links between human societies and the natural world because of their value as food, medicine, and biotechnological tools; and as sources of novel tools and approaches for conservation of megadiverse organism groups. We hope conservation professionals will value the potential of fungi, engage mycologists in their work, and appreciate the crucial role of fungi in nature. Una Perspectiva Micótica de la Biología de la Conservación  相似文献   
76.
生态价值多元化实现是落实区域一体化生态保护格局的经济政策保障。针对当前生态产品交易制度不完善与市场活跃度问题,以天目湖流域水质净化服务产品为例,提出一条生态保护市场化与生态产品增值的双向促进道路:基于长序列监测数据与水文水质过程模型,提出流域生态保护基准概念及其约束下生态产品交易边界,精准核算基准年水质净化产品的可交易量为1.37 t,基准价格为1186.71万元/t/年;面向近10年产品实际供需主体的内在联系,揭示了“三类五种”生态产品交易机制类型,并选择设计了低端产品退出—高端产品激励的典型交易模式。生态产品交易实施为研究区生态价值实现提供市场化路径,为国内同类地区一体化生态保护格局保障提供思路。  相似文献   
77.
Sulfonamides (SAs) are one of the most widely used antibiotics and their residuals in the environment could cause some negative environmental issues. Advanced oxidation such as Fenton-like reaction has been widely applied in the treatment of SAs polluted water. Degradation rates of 95%-99.7% were achieved in this work for the tested 8 SAs, including sulfisomidine, sulfameter (SME), phthalylsulfathiazole, sulfamethoxypyridazine, sulfamonomethoxine, sulfisoxazole, sulfachloropyridazine, and sulfadimethoxine, in the Fe3O4/peroxodisulfate (PDS) oxidation system after the optimization of PDS concentration and pH. Meanwhile, it was found that a lot of unknown oxidation products were formed, which brought up the uncertainty of health risks to the environment, and the identification of these unknown products was critical. Therefore, SME was selected as the model compound, from which the oxidation products were never elucidated, to identify these intermediates/products. With liquid chromatography-high resolution tandem mass spectrometry (LC-HRMS/MS), 10 new products were identified, in which 2-amino-5-methoxypyrimidine (AMP) was confirmed by its standard. The investigation of the oxidation process of SME indicated that most of the products were not stable and the degradation pathways were very complicated as multiple reactions, such as oxidation of the amino group, SO2 extrusion, and potential cross-reaction occurred simultaneously. Though most of the products were not verified due to the lack of standards, our results could be helpful in the evaluation of the treatment performance of SAs containing wastewater.  相似文献   
78.
Recent “green” planning initiatives envision food production, including urban agriculture and livestock production, as desirable elements of sustainable cities. We use an integrated urban political ecology and human–plant geographies framework to explore how foraging for “wild” foods in cities, a subversive practice that challenges prevailing views about the roles of humans in urban green spaces, has potential to also support sustainability goals. Drawing on research from Baltimore, New York City, Philadelphia, and Seattle, we show that foraging is a vibrant and ongoing practice among diverse urban residents in the USA. At the same time, as reflected in regulations, planning practices, and attitudes of conservation practitioners, it is conceptualised as out of place in urban landscapes and an activity to be discouraged. We discuss how paying attention to urban foraging spaces and practices can strengthen green space planning and summarise opportunities for and challenges associated with including foragers and their concerns.  相似文献   
79.
This article is an assessment of the current state of the art and relative utility of satellite precipitation products (SPPs) for hydrologic applications to support water management decisions. We present a review of SPPs, their accuracy in diverse settings including the influence of geography, topography, and weather systems, as well as the pros and cons of their use for different water management applications. At the end of this broad synthesizing effort, recommendations are proposed for: (1) SPP developers to improve the quality, usability, and relevance of precipitation products; and (2) SPP users to improve the reliability of their predictions and hydrologic applications to better support water management.  相似文献   
80.
研究连续2年秸秆还田下氮肥用量对玉米产量、氮肥利用率及土壤硝态氮的影响,结果表明,玉米产量随着施氮量的增加逐渐增加,施氮量达到216 kg·hm^-2时,产量最高,施氮量超过216 kg·hm^-2时产量有降低的趋势。相同施氮处理玉米产量年际变化明显,2010年较2009年产量提高0.69%~4.75%。氮肥利用率、氮肥农学利用率和氮收获指数随着秸秆还田年限的增加,均有不同程度的增加。2年0~100 cm土层土壤硝态氮含量均以施氮240 kg·hm^-2最高,且有向土壤深层迁移的趋势,对浅层地下水构成潜在的威胁。与施氮240 kg·hm^-2相比,施氮168、192 kg·hm^-2和216 kg·hm^-2处理0~100 cm土壤无机氮残留量2年平均减少39.87%、35.84%和29.38%。相同施氮处理,0~100 cm土壤无机氮累积量2010年较2009年略有降低。综合考虑玉米产量、氮肥利用率与生态环境效益,该地区最适施氮量200 kg·hm^-2左右。  相似文献   
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