基于双指标多等级的土壤重金属生态风险评价

采用土壤中重金属的全量和有效态双重指标,建立基于多等级综合评估的土壤中重金属生态风险评价模型,将联合概率曲线法引入土壤评价模型,分析重金属暴露浓度与毒性数据的概率分布,考察重金属对土壤生物的毒害程度,从而确定土壤中重金属对于生态系统的风险。建立从简单到复杂的多等级综合评价方法,表征重金属的污染等级、浓度效应、多种重金属污染物的协同效应、不同重金属的毒性效应和土壤对不同重金属污染物的敏感性。选择典型地区采集有代表性的土壤样品,测定不同重金属的总量和有效态,验证评价模型的实用性和评价分级的合理性。旨在解决土壤重金属风险评价的方法学问题,为土壤环境质量管理提供支持。     

环境规制、省际产业转移对污染迁移的空间溢出效应

目前我国正在积极地探寻经济增长高质量发展,生态环境与经济持续、稳定的和谐发展至关重要。虽然政府制定了相关的环境治理政策,但我国环境治理整体效果仍然欠佳。自从分税制改革以来,地方政府为了获得较高经济效益,会放松对环境管理,导致环境治理高投入低成效。同时,由于区域经济发展不平衡导致政府在制定相关环境治理政策时带有区域性特点,迫使高污染高能耗企业迁移至环境规制相对薄弱的地区,由此产生污染迁移的现象。基于此,对2003—2017年30个省区市(港澳台和西藏除外)环境污染总指数的空间溢出效应进行探讨,构建动态空间杜宾模型研究环境规制、省际产业转移对污染迁移的影响。研究结果表明:①环境规制总体上对环境污染具有显著直接效应且存在正向空间溢出效应,当某省环境规制强度增加,环境污染总指数会降低,从而引起污染向相邻省份转移,造成相邻省份的环境污染总指数上升。②省际产业转移整体上对环境污染具有显著直接效应且存在负向空间溢出效应,当某省的产业转移到相邻省份时,会缓解本省环境污染,却加重相邻省份的环境污染程度。这就需要中央政府加强对于各省区市的环境管控,统筹各区域的联防联治机制。产业转移承接省份在招商引资的过程中不仅要考虑本省环境承载能力和环境治理能力,还要考虑入驻企业自身污染排放处理能力,并将污染排放指数纳入筛选条件。同时,产业转移承接省份要引入企业的生产工艺、技术、研发团队等,运用技术溢出效应提升区域环境治理水平。     

Effects of climate and land-cover change on the conservation status of gibbons

Species shift their distribution in response to climate and land-cover change, which may result in a spatial mismatch between currently protected areas (PAs) and priority conservation areas (PCAs). We examined the effects of climate and land-cover change on potential range of gibbons and sought to identify PCAs that would conserve them effectively. We collected global gibbon occurrence points and modeled (ecological niche model) their current and potential 2050s ranges under climate-change and different land-cover-change scenarios. We examined change in range and PA coverage between the current and future ranges of each gibbon species. We applied spatial conservation prioritization to identify the top 30% PCAs for each species. We then determined how much of the PCAs are conserved in each country within the global range of gibbons. On average, 31% (SD 22) of each species’ current range was covered in PAs. PA coverage of the current range of 9 species was <30%. Nine species lost on average 46% (SD 29) of their potential range due to climate change. Under climate-change with an optimistic land-cover-change scenario (B1), 12 species lost 39% (SD 28) of their range. In a pessimistic land-cover-change scenario (A2), 15 species lost 36% (SD 28) of their range. Five species lost significantly more range under the A2 scenario than the B1 scenario (p = 0.01, SD 0.01), suggesting that gibbons will benefit from effective management of land cover. PA coverage of future range was <30% for 11 species. On average, 32% (SD 25) of PCAs were covered by PAs. Indonesia contained more species and PCAs and thus has the greatest responsibility for gibbon conservation. Indonesia, India, and Myanmar need to expand their PAs to fulfill their responsibility to gibbon conservation. Our results provide a baseline for global gibbon conservation, particularly for countries lacking gibbon research capacity.     

Environmental justice in Nigeria: A narration of residents’ experience in Ile-Ife

The sharing of environmental cost by residents in various residential areas in the developing world is perceived to be unfair. This study therefore assessed residents’ experiences of environmental justice in Ile-Ife, Nigeria. Three residential areas were identified in the study area and samples were selected using systematic sampling. Using availability and condition of urban infrastructure, severity of environmental problems and residents’ involvement in environmental issues, the study examined environmental justice in the study area. The study established a variation in environmental issues across identified residential areas. The severity of environmental problem measured through an index tagged Severity of Environmental Problem (SEPI) revealed that environmental problems was most severe in the core (SEPI = 4.00), followed by the peripheral area (SEPI = 3.71) and least in the transition area (SEPI = 3.56). On the condition of available environmental infrastructure, the study revealed that the conditions of infrastructure were most improved in the peripheral area (ICI = 3.07), followed by the core (ICI = 2.67) and the least in the transition area (ICI = 2.42). The study concluded that residents’ experiences of environmental justice differ significantly across the different residential zones as reflected by residents’ socio-economic characteristics. Furthermore, it established that age, gender, educational status, and number of years spent in the area can be used to explain the differences in residents’ experience of environmental justice in the study area. To enhance the liveability, the study recommends adequate provision of environmental amenities needed by each category of people in the city.     

A methodology for assessment of long-term exposure to whole-body vibrations in vehicle drivers to propose preventive safety measures

Introduction: The appearance of musculoskeletal disorders (MDs) in professional drivers due to exposition to whole-body vibration (WBV) makes it relevant to assess this exposure. The European Directive 2002/44/EC has two methods to evaluate exposure to WBV (defined in ISO2631-1:2008). These methods evaluate the exposure associated with an 8-hour working day; however, MDs due to WBV could also be caused by accumulated exposure to vibrations over long term, and hence, the methods defined in the European directive may be limited in their ability to ensure the safety of workers exposed to WBV throughout their years of employment. Method: A detailed comparison and discussion of methods defined in the European Directive and the ISO2631-5:2018 was used as a starting point of the main results of this paper. On this basis, a new methodology for the management and organization of preventive measures is proposed to consider the assessment of ISO2631-5:2018 standard and the full working life of workers. Experimental data to assess exposure to WBV in heavy equipment vehicle (HEV) drivers under different road surface conditions and range of velocities were considered to illustrate the process of the proposed methodology. Results: The methods defined in the standards provide different assessments leading to a different possible consideration of safe operations when the risks associated with them may actually be high. The proposed methodology can be used with the aim of ensuring safety of workers throughout their working lives and providing an easy implementation of the calculations of ISO2631-5:2018 standard. Conclusions: A procedure to assess the health risk probability to which the HEV worker is exposed in terms of the exposure years and a different range of operational vehicle speeds is proposed and exemplified with a study case. Practical applications: This study provides a practical tool for the management of WBV exposure related to work-tasks in HEV drivers. Safety managers should consider the global exposition to WBV throughout their working life, and this research provides an easy tool to accomplish it.     

Risk assessment method of polyethylene dust explosion based on explosion parameters

The explosion characteristic parameters of polyethylene dust were systematically investigated. The variations in the maximum explosion pressure (P_max), explosion index (K_st), minimum ignition energy (MIE), minimum ignition temperature (MIT), and minimum explosion concentration (MEC) of dust samples with different particle sizes were obtained. Using experimental data, a two-dimensional matrix analysis method was applied to classify the dust explosion severity based on P_max and K_st. Then, a three-dimensional matrix was used to categorize the dust explosion sensitivity based on three factors: MIE, MIT, and MEC. Finally, a two-dimensional matrix model of dust explosion risk assessment was established considering the severity and sensitivity. The model was used to evaluate the explosion risk of polyethylene dust samples with different particle sizes. It was found that the risk level of dust explosion increased with decreasing particle size, which was consistent with the actual results. The risk assessment method can provide a scientific basis for dust explosion prevention in the production of polyethylene.     

应用高频气力分选机分选电子废料碎片的研究

进行了实验室高频气力分选机分选3～0.3 mm印刷电(线)路板模拟物料的研究.结果表明,在振频为1 621次/min,上升风量为120 m3/h,95 m3/h,60 m3/h,床面横向倾角6.64°,纵向倾角为1.07°时,金属回收率达93.95%;重产物金属品位为89.19%;轻产物中非金属的品位达99.33%.0.5～0.3 mm细粒物料的分选效果也是令人满意的.     

湘江干流水环境健康风险评价

为研究湘江水环境污染对人体健康产生的危害风险,在简要介绍健康风险评价方法及国内外研究、应用进展的基础上,建立了水环境健康风险评价模式,应用2000年的水质监测资料,对湘江干流主要断面进行了水环境健康风险评价.结果表明,在所评价断面中,非致癌物质由饮水途径所致健康危害的个人年风险按大小排列为Pb＞Hg＞NH3＞酚;化学致癌物质由饮水途径所致健康危害的个人年风险按大小排列为As＞Cd;化学致癌物质对人体健康危害的个人年风险远超过非致癌物质;污染最为严重的为松柏断面,其次是五星断面和三叉矶断面.湘江干流衡阳以上江段水质良好,衡阳以下江段水质较差.研究对湘江干流水污染防治方略的制定具有一定价值.     

低剂量镉诱导细胞氧化损伤的机理研究

镉是一种有毒重金属,能诱导酿酒酵母的氧化损伤.为了研究低剂量镉诱导细胞氧化损伤的作用,通过有葡萄糖和无葡萄糖的酵母培养基,用浓度2 μmol/L和10 μmol/L的CdCl2染毒酿酒酵母10 h后,统计酿酒酵母细胞的存活率,并用HPLC-EC法测定酿酒酵母线粒体DNA中8-OH-dG/105dG比值.结果表明:无葡萄糖条件下,10μmol/L的CdCl2染毒时酿酒酵母对Cd2 的耐受性比有葡萄糖时明显高(P＜0.01),而且线粒体DNA氧化损伤程度也明显低(P＜0 01);但2 μmol/L的CdCl2染毒时,酿酒酵母对Cd2 的耐受性和线粒体DNA氧化损伤程度与有葡萄糖条件下相比差异不显著(P＞0.05).因此,本文认为低浓度Cr主要对酿酒酵母细胞质中蛋白造成氧化损伤,浓度升高时则对线粒体DNA也产生氧化损伤.     

久效磷对黄鳝乙酰胆碱酯酶、羧酸酯酶和磷酸酶活性的影响

采用静态急性毒性实验方法,研究了久效磷对黄鳝脑乙酰胆碱酯酶及肝脏、肾脏羧酸酯酶、碱性磷酸酶、酸性磷酸酶活性的影响.结果表明,在水温(20±2)℃条件下,经0.25 mg·L-1、0.50 mg·L-1、1.00mg·L-1和2.00mg·L-1的久效磷暴露96 h,黄鳝肝脏、肾脏羧酸酯酶和脑乙酰胆碱酯酶活性均显著下降,但两者表现出不同的抑制模式.随着暴露质量浓度的升高,肝脏和肾脏羧酸酯酶活性的下降幅度逐渐变小,而脑乙酰胆碱酯酶活性下降幅度却由小变大.久效磷暴露黄鳝96 h,肝脏、肾脏酸性磷酸酶活性均升高;而肝脏碱性磷酸酶活性升高;肾脏碱性磷酸酶活性降低.久效磷暴露质量浓度与脑乙酰胆碱酯酶和肝脏、肾脏羧酸酯酶活性之间具有剂量-效应关系,酸性磷酸酶和碱性磷酸酶可能在鱼体抵御有机磷农药毒性作用中有着重要的作用,其机理有待进一步研究.此外,本文还探讨了有机磷农药靶标酶乙酰胆碱酯酶和解毒酶羧酸酯酶、磷酸酶之间的相关性.