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91.
Conservation biology is a mission-driven discipline that must navigate a new relationship between conservation and science. Because conservation is a social and political as well as an ecological project, conservation biologists must practice interdisciplinarity and collaboration. In a comparative study of 7 cases (Jaguars in the Chaco, Grevy's zebra in Kenya, Beekeeping in Tanzania, Andean cats in Argentina, Jaguars in Mexico, Lobster fishing, and Black bears in Mexico), we examined motivations for collaboration in conservation, who can collaborate in conservation, and how conservation professionals can work well together. In 5 case studies, successful conservation outcomes were prioritized over livelihood benefits. In the other 2 cases, livelihoods were prioritized. All case studies employed participatory approaches. There were multiple external actors, including local and Indigenous communities, nongovernmental organizations, agencies, regional and national governments, and international organizations, which enhanced conservation and wider sustainability outcomes. Key collaboration aspects considered across the case studies were time (mismatch between relationship building and project schedules), trust required for meaningful partnerships, tools employed, and transformative potential for people, nature, and the discipline of conservation biology. We developed guidelines for successful collaboration, including long-term commitment, knowledge integration, multiscalar and plural approaches, cultivation of trust, appropriate engagement, evaluation, supporting students, and efforts for transformation.  相似文献   
92.
通过微涡旋絮凝逆流气浮-纳滤集成工艺的动态试验研究,确定其运行周期为72 h,能很好地去除水中腐殖酸有机物,但不同纳滤膜组成的集成工艺处理效果不同.采用PACl絮凝剂处理水样2时,以流程1运行的含TQ56-36FC型纳滤膜的集成工艺出水的高锰酸盐指数为0.45 mg/L,UV254nm在0.003 3左右波动,且有95%以上的脱盐率.以流程2运行的含M-N1812A型纳滤膜的集成工艺处理3种水样时的膜清水的高锰酸盐指数在0.75 mg/L左右波动,UV254nm大都远小于0.007 5,有时甚至为0.水样1和水样3的UV254nm平均值为0.005 4,水样2的最低,平均值为0.003 3,脱盐率只有6%~10%.以PACl为絮凝剂时,集成系统有较强的适应原水水质变化的能力.预处理中活性炭柱的存在提高了M-N1812A型纳滤膜清水样的水质,但并没有延长膜的使用周期.这也表明膜的污染更重要的是来自无机物的污染.  相似文献   
93.
就目前的情况而言,我国在社会环境检测机构质量不容乐观。因此,我们应该根据实际情况,来设置相应的社会环境检测监管方案。我们可以通过严格规范社会环境检测机构市场准入门槛、创设专门的社会环境检测机构质量监管部门、创设社会环境检测机构网上投诉平台等方式,来提升监管力度,让社会环境检测机构正确发挥其应有的作用。  相似文献   
94.
娄伟  宋典  王琦  肖启学  彭春雷 《环境与发展》2020,(4):252-252,254
为贯彻落实《中华人民共和国环境保护法》,加强建设用地土壤环境监管,管控污染地块对人体健康的风险,保障人居环境安全,生态环保部组织相关部门编制了土壤环境质量标准,并于2018年8月1日起开始实施。在标准实施的过程和应用过程中发现新发布的标准存在一些局限性。本文以土壤污染机理为基础,结合现行的治理技术,论述土壤质量标准在时间、空间及应用中的局限性。  相似文献   
95.
A gas monitoring system based on broadband absorption spectroscopic techniques in the ultraviolet region is described and tested. The system was employed in real-time continuous concentration measurements of sulfur dioxide (SO2) and nitric oxide (NO) from a 220-ton h?1 circulating fluidized bed (CFB) boiler in Shandong province, China. The emission coefficients (per kg of coal and per kWh of electricity) and the total emission of the two pollutant gases were evaluated. The measurement results showed that the emission concentrations of SO2 and NO from the CFB boiler fluctuated in the range of 750–1300 mg m?3 and 100–220 mg m?3, respectively. Compared with the specified emission standards of air pollutants from thermal power plants in China, the values were generally higher for SO2 and lower for NO. The relatively high emission concentrations of SO2 were found to mainly depend on the sulfur content of the fuel and the poor desulfurization efficiency. This study indicates that the broadband UV spectroscopy system is suitable for industrial emission monitoring and pollution control.  相似文献   
96.
海滨填埋场是沿海地区垃圾处理的一个重要选择,但其渗滤液泄漏引发的地下环境污染具有一定的独特性。以渗滤液中长时间保持高浓度的氨氮作为指标,通过构建砂箱实验,探讨咸水条件下氨氮在地下环境中的迁移转化过程。结果表明,在地下水环境中,渗滤液氨氮较易沿水流水平方向扩散,扩散速度随空间推移不断降低,从开始的4 cm/d降低到出水处的3.2 cm/d;其衰减率沿饱和区、过渡区、调整区依次增高;同时其衰减率随时间的增加不断降低,在实验的第15、25、35、45和55天,分别为100%、98.7%、95.6%、91.8%和83.5%。  相似文献   
97.
Abstract

This paper concerns the incineration of isopropyl alcohol (IPA) using the ferrospinel catalyst MnFe2O4. It covers the preparation of the ferrospinel catalyst, the screening of catalytic activity, catalytic incineration testing, and 72-hr decay testing of the catalyst. The experimental results of catalyst screening reveal that the Mn/Fe catalyst is the best of five prepared catalysts (chromium/iron [Cr/Fe], manganese/iron [Mn/Fe], zinc/iron [Zn/Fe], nickel/iron [Ni/Fe], and pure magnetite [Fe3O4]). In tests of the catalytic incineration system used to convert IPA, 98% conversion was obtained at a space velocity of 24,000 hr?1, an oxygen (O2) content of 21%, 1700 ppm of IPA, and a reaction temperature of 200 °C.  相似文献   
98.
Field studies were conducted to investigate arsenic (As), copper (Cu), and zinc (Zn) contamination in agricultural soils and wheat crops at two areas in Huaibei, China. Area A is in the proximity of Shuoli coal mine. In area B, three coal mines and a coal cleaning plant were distributed. The potential health risk of As, Cu, and Zn exposure to the local inhabitants through consumption of wheat grains was also estimated. The results showed that significantly higher (p?<?0.05) concentrations of As, Cu, and Zn were found in soils collected from area B than in those from area A. Arsenic concentrations in wheat sampled from area A were negatively correlated with the distance from the coal mine (p?<?0.001). Concentrations of Cu and Zn in wheat seedlings and grains collected from area B were significantly higher (p?<?0.05) than in those collected from area A, with the exception of Zn in wheat seedlings. Concentrations of Cu and Zn in most wheat grain samples were above the permissible limits of Cu and Zn in edible plants set by the Food and Agriculture Organization/World Health Organization. The hazard index of aggregate risk through consumption of wheat grains was 2.3–2.4 for rural inhabitants and 1.4–1.5 for urban inhabitants. The average intake of inorganic As for rural inhabitants in Huaibei was above 10 μg day?1. These findings indicated that the inhabitants around the coal mine are experiencing a significant potential health risk due to the consumption of locally grown wheat.  相似文献   
99.
Body size-dependent mating pattern is thought to a consequence of the sexual selection on phenotypic characters. In the view, we investigated the mating patterns in Bufo andrewsi from three populations at different latitude in three Nature Reserves (i.e. Wanglang, Yele and Fengtongzhai) in China from early- March to late-May 2013 and 2014. The results showed that average body size did not differ significantly between amplectant and non-amplectant males within each population. We found a significantly positive relationship in body size between the amplectant males and amplectant females in Wanglang population, but not in Qiqiao and Yele populations. The strength of size-dependent mating was not correlated with the malebiased operational sex ratios (OSRs), suggesting that intensity of male-male competition at nights do not result in variation in size-dependent mating patterns in B. andrewsi among populations.  相似文献   
100.
Severe particulate matter (PM, including PM2.5 and PM10) pollution frequently impacts many cities in the Yangtze River Delta (YRD) in China, which has aroused growing concern. In this study, we examined the associations between relative humidity (RH) and PM pollution using the equal step-size statistical method. Our results revealed that RH had an inverted U-shaped relationship with PM2.5 concentrations (peaking at RH = 45–70%), and an inverted V-shaped relationship (peaking at RH = 40 ± 5%) with PM10, SO2, and NO2. The trends of polluted-day number significantly changed at RH = 70%. The very-dry (RH < 45%), dry (RH = 45–60%) and low-humidity (RH = 60–70%) conditions positively affected PM2.5 and exerted an accumulation effect, while the mid-humidity (RH = 70–80%), high-humidity (RH = 80–90%), and extreme-humidity (RH = 90–100%) conditions played a significant role in reducing particle concentrations. For PM10, the accumulation and reduction effects of RH were split at RH = 45%. Moreover, an upward slope in the PM2.5/PM10 ratio indicated that the accumulation effects from increasing RH were more intense on PM2.5 than on PM10, while the opposite was noticed for the reduction effects. Secondary transformations from SO2 and NO2 to sulfate and nitrate were mainly responsible for PM2.5 pollution, and thus, controlling these precursors is effective in mitigating the PM pollution in the YRD, especially during winter. The conclusions in this study will be helpful for regional air-quality management.  相似文献   
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