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1.
Biodiversity offsets aim to counterbalance the residual impacts of development on species and ecosystems. Guidance documents explicitly recommend that biodiversity offset actions be located close to the location of impact because of higher potential for similar ecological conditions, but allowing greater spatial flexibility has been proposed. We examined the circumstances under which offsets distant from the impact location could be more likely to achieve no net loss or provide better ecological outcomes than offsets close to the impact area. We applied a graphical model for migratory shorebirds in the East Asian–Australasian Flyway as a case study to explore the problems that arise when incorporating spatial flexibility into offset planning. Spatially flexible offsets may alleviate impacts more effectively than local offsets; however, the risks involved can be substantial. For our case study, there were inadequate data to make robust conclusions about the effectiveness and equivalence of distant habitat-based offsets for migratory shorebirds. Decisions around offset placement should be driven by the potential to achieve equivalent ecological outcomes; however, when considering more distant offsets, there is a need to evaluate the likely increased risks alongside the potential benefits. Although spatially flexible offsets have the potential to provide more cost-effective biodiversity outcomes and more cobenefits, our case study showed the difficulty of demonstrating these benefits in practice and the potential risks that need to be considered to ensure effective offset placement.  相似文献   
2.
● China has pledged ambitious carbon peak and neutrality goals for mitigating global climate change. ● Major challenges to achieve carbon neutrality in China are summarized. ● The new opportunities along the pathway of China’s carbon neutrality are discussed from four aspects. ● Five policy suggestions for China are provided. China is the largest developing economy and carbon dioxide emitter in the world, the carbon neutrality goal of which will have a profound influence on the mitigation pathway of global climate change. The transition towards a carbon-neutral society is integrated into the construction of ecological civilization in China, and brings profound implications for China’s socioeconomic development. Here, we not only summarize the major challenges in achieving carbon neutrality in China, but also identify the four potential new opportunities: namely, the acceleration of technology innovations, narrowing regional disparity by reshaping the value of resources, transforming the industrial structure, and co-benefits of pollution and carbon mitigation. Finally, we provide five policy suggestions and highlight the importance of balancing economic growth and carbon mitigation, and the joint efforts among the government, the enterprises, and the residents.  相似文献   
3.
利用液液萃取(LLE)与固相萃取法(SPE)提取和净化人体指甲中的多溴联苯醚(PBDEs)和多氯联苯(PCBs),经浓硫酸除脂后,利用气相色谱-质谱联用仪(GC-MS)测定PBDEs和PCBs.对提取溶剂比例、净化柱类型(复合硅胶柱与固相萃取柱)、固相萃取条件(洗脱溶剂及体积)以及脂肪的去除方法进行了优化,加标回收率较前人基础上均有明显提高.加标回收试验结果显示,PBDEs和PCBs平均基质加标回收率分别为90%—110%和71%—102%,空白加标回收率分别为70%—110%和60%—100%之间,仪器检出限(IDL)分别为0.034—0.120μg·L~(-1)和0.032—0.392μg·L~(-1).本方法快速、简单、高效,能够满足指甲中PBDEs和PCBs的分析.同时本研究利用该方法对电子垃圾拆解地区居民的指甲样品进行测定,PBDEs和PCBs平均浓度分别为623 ng·g~(-1)和148 ng·g~(-1),BDE(-154、-153、-183、-209)和PCB(-8、-28、-52、-66、-101、-77、-118、-153、-187)在所有样品中均检出,女性指甲中PBDEs与PCBs的浓度普遍高于男性.  相似文献   
4.
过去40年来我国经济建设取得了举世瞩目的成绩,但是也留下了很多生态环境问题。目前我国经济已经由高速增长阶段转向高质量发展阶段,但高质量发展缺乏指标体系和具体路径。“三线一单”是一套生态环境分区管控体系,其主要目的是统筹地方社会经济与环境保护的矛盾,促进经济结构转型。四川省在“三线一单”编制过程中,通过建立指标体系从生态环境保护的角度为地区高质量发展提供了量化标准,通过差异化管控要求为地区高质量发展提供了具体路径,从生态环境角度助力高质量发展。  相似文献   
5.
介绍了燃煤电厂超低排放气态污染物监测系统的采样系统和分析单元,分析了其各自的优缺点。对稀释抽取式、冷干抽取式和热湿抽取式3种采样方法,以及非分散红外吸收法(NDIR)、非分散紫外吸收法(NDUV)、紫外差分吸收法(DOAS)、紫外荧光法(UVF)和化学发光法(CL)5种分析方法进行对比。结果表明,冷干抽取式+紫外差分法以及稀释抽取式+紫外荧光法+化学发光法可以较好地符合燃煤电厂超低排放监测的要求。  相似文献   
6.
采用溶胶-凝胶法制备了Mn掺杂钙钛矿型催化剂LaFexMn1-xO3,并以其为催化剂催化湿式双氧水氧化处理煤气化废水纳滤浓缩液。采用XRD,SEM,FTIR技术对催化剂进行了表征。表征结果显示:制备的催化剂均具有标准的钙钛矿型结构,其中,LaFe0.9Mn0.1O3的结构稳定,比表面积大。实验结果表明:制备的催化剂中LaFe0.9Mn0.1O3的催化活性最高,且稳定性好,连续使用5次后催化活性未见明显减弱;在H2O2投加量3.0 g/L、n(H2O2)∶n(LaFe0.9Mn0.1O3)=12∶1、反应温度160 ℃、反应压力1 MPa、浓缩液pH 3、反应时间60 min的最优条件下,COD、UV254和TOC的去除率分别达到80.9%、95.2%和68.0%,BOD5/COD由0.02提升至0.40,可生化性大幅提高。  相似文献   
7.
Concentrations of eight trace metals (TMs) in road dust (RD) (particles?<?25 μm) from urban areas of Xinxiang, China, were determined by inductively coupled plasma mass spectrometry. The geometric mean concentrations of Zn, Mn, Pb, As, Cu, Cr, Ni and Cd were 489, 350, 114, 101, 60.0, 39.7, 31.6, and 5.1 mg kg?1, respectively. When compared with TM levels in background soil, the samples generally display elevated TM concentrations, except for Cr and Mn, and for Cd the enrichment value was 69.6. Spatial variations indicated TMs in RD from park path would have similar sources with main roads, collector streets and bypasses. Average daily exposure doses of the studied TMs were about three orders of magnitude higher for hand-to-mouth ingestion than dermal contact, and the exposure doses for children were 9.33 times higher than that for adults. The decreasing trend of calculated hazard indexes (HI) for the eight elements was As?>?Pb?>?Cr?>?Mn?>?Cd?>?Zn?>?Ni?>?Cu for both children and adults.  相似文献   
8.
利用2013-2017年京津冀区域13个城市PM2.5监测数据,综合探讨了该区域PM2.5浓度的时空变化特征。结果表明:京津冀区域PM2.5污染整体较重,但治理成效显著,2013-2017年区域PM2.5年均质量浓度分别为106、93、77、71、64 μg/m3,完成《大气污染防治行动计划》PM2.5浓度下降25%左右的目标;13个城市PM2.5浓度各百分位数总体呈现下降趋势,且随百分位数增大而下降速率加大,PM2.5年均质量浓度平均每年下降10.6 μg/m3,污染严重的太行山沿线城市邢台、石家庄、邯郸3个城市平均每年分别下降20.3、16.1、13.9 μg/m3;京津冀区域PM2.5重度污染天数比例分别为19.9%、16.6%、9.5%、9.0%、7.0%,呈下降趋势。2013-2017年京津冀区域PM2.5平均质量浓度与非重度污染天相比升高19 μg/m3,PM2.5重度污染天平均质量浓度较非重度污染天时高244.4%。  相似文献   
9.

As an important renewable energy source, wind power plays a key role in mitigating climate change and has become one of the fastest growing clean energies globally. In China, wind energy development has been a vital component of national energy transformation strategy. Over the years, the Chinese government has introduced a series of policies to promote the development of wind power and also to regulate this emerging industry. Base on examining all the key policy documents on wind power issued by the Chinese government over the last 30 years, we find that China has built up a comprehensive policy system, and summarized the current framework of Chinese wind power policy systematically. Then, we analyze the policy objectives, policy tools, major measures, their results in each development stage, and the characteristics and trends of China’s wind power policies. Finally, we discuss the limitations of the current policy and put forward corresponding suggestions.

  相似文献   
10.
T-2 toxin (T-2), one of the naturally occurring mycotoxins, often accumulates in aquatic animals from contaminated feed. Shrimp (n?=?30 per group) were fed with different concentrations (0, 0.5, 1.5, 4.5 and 13.5?mg kg?1) of T-2 for 20?days. Changes in histopathology, fatty acid and water distribution of shrimp muscle were analyzed. Histopathology of shrimp muscle showed dose-dependent marked degenerative and necrotic changes on exposure to dietary T-2. The T-2 significantly (P?<?0.05) affected the muscle fatty acid composition. ∑SFA, ∑MUFA and ∑PUFA initially decreased and then increased slowly in the high-dosed groups. C16:0, C18:1n-9 and C18:2n-6 were the main saturated fatty acid (SFA), monounsaturated fatty acid (MUFA) and polyunsaturated fatty acid (PUFA), respectively. Also, T-2 significantly affected water distribution in shrimp muscle. High doses of T-2 reduced free water content, resulting in a reduction in the water holding capacity and hence changes to the shrimp muscle quality. Collectively, these results illustrated that T-2 significantly affects the fatty acid and water distribution, and also muscle histopathology, all of which would result in a reduction in the quality and nutritional value of shrimp.  相似文献   
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