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631.
Virginie Marques Paul Castagné Andréa Polanco Fernández Giomar Helena Borrero-Pérez Régis Hocdé Pierre-Édouard Guérin Jean-Baptiste Juhel Laure Velez Nicolas Loiseau Tom Bech Letessier Sandra Bessudo Alice Valentini Tony Dejean David Mouillot Loïc Pellissier Sébastien Villéger 《Conservation biology》2021,35(6):1944-1956
Assessing the impact of global changes and protection effectiveness is a key step in monitoring marine fishes. Most traditional census methods are demanding or destructive. Nondisturbing and nonlethal approaches based on video and environmental DNA are alternatives to underwater visual census or fishing. However, their ability to detect multiple biodiversity factors beyond traditional taxonomic diversity is still unknown. For bony fishes and elasmobranchs, we compared the performance of eDNA metabarcoding and long-term remote video to assess species’ phylogenetic and functional diversity. We used 10 eDNA samples from 30 L of water each and 25 hr of underwater videos over 4 days on Malpelo Island (pacific coast of Colombia), a remote marine protected area. Metabarcoding of eDNA detected 66% more molecular operational taxonomic units (MOTUs) than species on video. We found 66 and 43 functional entities with a single eDNA marker and videos, respectively, and higher functional richness for eDNA than videos. Despite gaps in genetic reference databases, eDNA also detected a higher fish phylogenetic diversity than videos; accumulation curves showed how 1 eDNA transect detected as much phylogenetic diversity as 25 hr of video. Environmental DNA metabarcoding can be used to affordably, efficiently, and accurately census biodiversity factors in marine systems. Although taxonomic assignments are still limited by species coverage in genetic reference databases, use of MOTUs highlights the potential of eDNA metabarcoding once reference databases have expanded. 相似文献
632.
Xiaojun Wang Jijun Han Zhiwei Chen Lei Jian Xiaoyang Gu Che-Jen Lin 《Waste management (New York, N.Y.)》2012,32(12):2401-2405
There are numerous non-biodegradable organic materials in the mature landfill leachate. To meet the new discharge standard of China, additional advanced treatment is needed for the effluent from the biological treatment processes of leachate. In this study, a combined process including two stages of “Fenton-biological anaerobic filter (BANF)–biological aerated filter (BAF)” was evaluated to address the advanced treatment need. The Fenton oxidation was applied to reduce chemical oxygen demand (COD) and enhance biodegradability of refractory organics, and the BANF–BAF process was then applied to remove the total nitrogen (TN). The treatment achieved effluent concentrations of COD < 70 mg/L, TN < 40 mg/L and NH3–N < 10 mg/L. The removal efficiency of COD and TN were 96.1% and 95.9%, respectively. The effluent quality met the new discharge standard for Pollution Control on the Landfill Site of Municipal Solid of PR China (GB16889-2008). The operation cost of these processes was about 36.1 CHY/t (5.70 USD/t). 相似文献
633.
Yeo Sang Gu Nhai Nguyen Thi Huong Dong Jong-In 《Journal of Material Cycles and Waste Management》2018,20(3):1615-1624
Journal of Material Cycles and Waste Management - Although waste-to-energy (WtE) may reduce the amount of waste disposed and recover the heat in the form of electricity or steam, it has limitations... 相似文献
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635.
已填垃圾的沉降分析是正确评估填埋场服务年限和合理确定填埋厚度的重要依据,根据陈垃圾的形成机制、沉降模型、计算方法以及及有关参数,并结合工程实例对填埋过程中的垃圾沉降发展过程进行了研究,确定了陈垃圾土的沉降特性。 相似文献
636.
Chao HE Zhaolin GU Shucheng YANG Jidong LIANG Weina DAI Yanling HE 《Frontiers of Environmental Science & Engineering》2010,4(4):466-474
China’s paper production reached 79.8 ×106 t in 2008 and ranked number one in the world. Because of its high consumption of water, energy and materials and its serious pollution, the present processes are not likely to be sustainable. An alternative, the closed Water Loop-Papermaking Integration (WLPI) method, is put forward in this paper. The WLPI method can be realized in a recycled paper mill by adding technologies and using recycled water. Many industrial case studies have shown that a large quantity of water, energy and materials can be saved, and the quantity of waste sludge and wastewater discharge was minimized by using the WLPI method. The design of the water reuse system, control of calcium hardness, water recycling and minimal waste sludge are discussed. Anaerobic technology plays an important role in the WLPI method to lower cost, energy use and waste. In the brown paper and coated white board production, zero-effluent discharge can be realized. Fresh water consumption is only 1–2 m3·t-1. For the paper mills with deinking and bleaching processes, about 10 m3·t-1 of fresh water and a similar amount of effluent discharge are needed. Power saving using anaerobic technology is 70% when recycled water is used in comparison with the conventional activated sludge process. Waste sludge can be decreased to about 5% of the initial process due to reuse of the waste sludge and the lower bio-sludge production of the anaerobic process. 相似文献
637.
采用全封闭式膜生物反应器处理医院污水,出水水质良好,ρ(COD)<60 mg/L,ρ(NH3-N)<6 mg/L,浊度<0.3NTU的概率约为95%,ClO2消毒后出水中未检测出细菌和粪大肠菌群,可满足GB 18466—2005《医疗机构水污染物排放标准》的要求。高效过滤器对曝气尾气中的微生物粒子截留效果良好,大大降低了MBR系统因气溶胶扩散可能产生的二次污染和威胁。此外采用了远程监控技术,可以通过公共网络对污水处理系统进行监视和控制,最大限度地保证系统的稳定运行和保障操作人员的生命安全。 相似文献
638.
Acute toxicities (15min‐EC50) of 21 substituted benzaldehydes to Photobacterium phosphoreum were determined. A quantitative structure‐activity relationship (QSAR) was developed using molecular connectivity indices and quantum chemical parameters, which show that the toxicity is influenced mainly by the difference of the simple and valence‐corrected fourth path molecular connectivity, polarizability, dipole moment, and the most negative net atomic charge on an atom. This study further shows that benzaldehydes are reactive chemicals, which exhibit bioreactive toxicity. 相似文献
639.
640.
煤矿是我国的首要能源企业,也是伤亡事故和职业病最严重的企业.仅尘肺病患者每年新增2000多人.伤亡事故和职业病造成的经济损失高达几百亿人民币. 相似文献