锡盟铁锌矿区土壤中重金属含量及有机质、pH值的分析

本文经过对锡盟东乌旗铁锌矿区中各个地点所采集的样品分析表明：在土样中，随着土壤深度的增加，重金属含量呈高-低-高的趋势；土样的PH值，亦呈现低-高-低的趋势；有机质的含量分布呈现由上到下逐渐减小的趋势。     

北京市平原区地下水污染防控区划不确定性分析

地下水污染防控区划对地下水保护、污染有效防治和管理有着重要的意义.以北京市平原区为背景建立了以污染风险评价、地下水价值和地下水源保护区三者叠加分析的地下水污染防控区划,为了得到更准确的地下水污染防控区划,本研究对其进行了不确定性分析.通过改变毒性、迁移性和降解性的权重值和地下水污染风险、地下水价值和地下水源保护区的权重值对其进行敏感性分析,研究结果表明,地下水污染风险、地下水价值和地下水源保护区的权重值比毒性、迁移性和降解性的权重值更为敏感.     

Climate Change Impacts on Local Flood Risks in the U.S. Northeast: A Case Study on the Connecticut and Merrimack River Basins

This study investigates the potential impacts of climate change on future flows in the main stem of the Connecticut and Merrimack rivers within Massachusetts. The study applies two common climate projections based on (Representative Concentration Pathways), RCP 4.5 and RCP 8.5 and downscaled gridded climate projections from 14 global climate models (GCMs) to estimate the 100‐year, 24‐h extreme precipitation events for two future time‐periods: near‐term (2021–2060) and far‐term (2060–2099). 100‐year 24‐h precipitation events at near‐ and far‐term are compared to GCM‐driven historical extreme precipitation events during a base period (1960–1999) and results for RCP 8.5 scenario show average increases between 25%–50% during the near‐term compared to the base period and increases of over 50% during the far‐term. Streamflow conditions are generated with a distributed hydrological model where downscaled climate projections are used as inputs. For the near‐term, the medians of the GCMs using the RCP 4.5 and RCP 8.5 suggest 2.9%–8.1% increases in the 100‐year, 24‐h flow event in the Connecticut and an increase of 9.9%–13.7% in the Merrimack River. For the far‐term, the medians of the GCMs using the RCP 4.5 and RCP 8.5 suggest a 9.0%–14.1% increase in the Connecticut and 15.8%–20.6% for the Merrimack River. Ultimately, the results presented here can be used as a guidance for the long‐term management of infrastructures on the Connecticut and Merrimack River floodplains.     

农业光伏电站综合效益评估研究——以浙江某150兆瓦项目为例

农光互补项目具有能源生产和粮食种植的双重价值,开展农业光伏电站的综合效益评估,有助于量化项目的实施效果,促进项目可持续发展。基于生态系统服务价值理论,本文构建了农业光伏电站的综合效益评估体系,并结合实地调查,以浙江乐清市某150兆瓦农光互补光伏发电项目为例进行了示范研究,分析了电站2018—2021年综合效益的构成和变化,比较了电站不同土地利用类型的生态系统服务差异,探讨了不同生态系统服务之间的协同与权衡关系。结果表明：(1)电站每年的经济效益在7534.11万～8417.06万元,电力效益上下波动,农业收益稳步增长;(2)随着项目的实施,电站的生态系统服务价值呈现“先减少后增加”的变化,总体增长量为435.31万元,单位面积生态价值从7.16万元/公顷提升至8.52万元/公顷,说明此农光互补模式对生态系统有积极影响;(3)由于光伏板下杂草区向水稻区的转变,电站的水源涵养和空气净化功能略微降低,土壤保持功能基本不变,而洪水调蓄和固碳释氧功能大幅增长;(4)光伏板的存在导致电站固碳和释氧功能的下降,而在光伏板下种植水稻改善了这一状况,并使电站的土壤保持和洪水调蓄功能发挥了较大作用;(5)...     

Ethical Tools to Support Systematic Public Deliberations about the Ethical Aspects of Agricultural Biotechnologies

This special issue of the Journal of Agricultural and Environmental Ethics presents so-called ethical tools that are developed to support systematic public deliberations about the ethical aspects of agricultural biotechnologies. This paper firstly clarifies the intended connotations of the term “ethical tools” and argues that such tools can support liberal democracies to cope with the issues that are raised by the application of genetic modification and other modern biotechnologies in agriculture and food production. The paper secondly characterizes the societal discussion on agricultural biotechnology and defends the thesis that normative perspectives fuel this discussion, so one cannot come to grips with this discussion if one neglects these perspectives. The paper thirdly agrues that no such thing exists as “one” societal debate in which these issues should be discussed. There are several interwined debates, and different actors participate in different discourses. Some practical instruments are necessary in order to include the right issues in these debates. These instruments will be coined as “ethical tools,” since they are practical instruments that can be used (tools) in order to support debates and deliberative structures for a systematic engagement with ethical issues (hence, ethical tools). Finally, the paper clarifies the ethics of these ethical tools and presents the tools as discussed in the remainder of this special issue: 1) tools to include ethical issues in public consulation and involvement; 2) tools to support systematic reflection upon ethical issues in decision-making; and 3) tools to support explicit communication about values in the food chain.     

含硫气田恶臭气体阈限值与恶臭强度的关系

介绍了恶臭强度的6级分类法,针对含硫气田典型的5种含硫恶臭化合物,利用韦伯-费希纳公式研究了气体浓度和恶臭强度的关系,计算并分析了我国环境标准和职业卫生标准规定的阈限值对应的恶臭强度。GB/T14554—1993《恶臭污染物排放标准》规定一级厂界浓度标准限值对应的恶臭强度为2.5左右,二级新改扩建厂界标准限值对应恶臭强度为2.8左右。我国国家职业卫生标准GBZ 2.1—2007中规定的含硫恶臭气体职业接触限值对应的恶臭强度均在4以上。     

欧盟工业废水污染物排放限值的制定方法

依据欧盟委员会的IPPC指令和水框架指令，欧盟成员国目前在制定废水污染物排放限值时，都以最佳可得技术（BAT）为参考，同时运用反演的方法将污染物排放限值与环境质量标准相结合。阐述了欧盟国家制定废水污染物排放限值的“BAT法”和“质量标准反演法”，并举例分析了“质量标准反演法”。提出了我国借鉴欧盟方法的几点建议。     

pH值对餐厨垃圾厌氧发酵产挥发性脂肪酸的影响

通过间歇实验研究了中温条件下pH值对餐厨垃圾厌氧发酵产挥发性脂肪酸(VFA)的影响.考察了pH值为5.0、6.0、7.0及不控制pH值下的有机酸浓度及组成情况.结果表明,当控制反应器中pH值为6.0时,餐厨垃圾水解酸化效果最好,比其他pH值条件下产生更多的有机酸.pH值为6.0时,VFA浓度与单位VS产酸量在第68h达到最大值,分别为40.89g/L和0.328gVFA/gVS,是不控制pH值时的8倍.pH值对发酵产物组成影响显著.不控制pH值时,反应器内的pH值在24h内由6.6迅速下降到3.8,乙醇为主要的发酵产物,占59.8%,表现为典型的乙醇型发酵.当控制pH值为5.0、6.0、7.0时,均为丁酸型发酵.但pH值为5.0时,乙酸为主要产物;pH值为6.0时,丁酸为主要产物;pH值为7.0时,乙酸与丁酸比例相当.试验表明,餐厨垃圾厌氧发酵产酸的最佳pH值为6.0.     

Experimental study on MSW gasification and melting technology

In order to develop municipal solid waste (MSW) gasification and melting technology, two preliminary experiments and a principle integrated experiment were fulfilled respectively. The gasification characteristics of MSW are studied at 500-750℃ when equivalence ratio (ER) was 0.2-0.5 using a fluidized-bed gasifier. When temperature was 550-700℃ and ER was 0.2-0.4, low heat value (LHV) of syngas reaches 4000-12000 kJ/Nm3. The melting characteristics of fly ash were investigated at 1100-1460℃ using a fixed-bed furnace. It was proved that over 99.9% of dioxins could be decomposed and most heavy-metals could be solidified when temperature was 1100-1300℃. The principle integrated experiment was carried out in a fluidized-bed gasification and swirl-melting system. MSW was gasified efficiently at 550-650℃, swirl-melting furnace maintains at 1200-1300℃ stably and over 95% of fly ash could be caught by the swirl-melting furnace. The results provided much practical experience and basic data to develop MSW gasification and melting technology.     

北方农牧交错带降水极值变化空间特征

农牧交错带是我国生态环境脆弱带,以109个气象站1971～1998年间的逐日降水资料,分析了农牧交错带年降水量、侵蚀性降水及暴雨等方面降水极值的时间变化及空间分布。结果显示农牧交错带平均每年发生侵蚀性降水的日数在3.5～17.6d之间,暴雨日数在0～2.6d之间;大部分地区的年降水量、侵蚀性降水量及暴雨量等都呈现不同程度的增加趋势,但暴雨量以及侵蚀性降水量等降水极值指标增加趋势更明显,反映出多数地区降水强度增加、降水侵蚀的潜在能力增强的特征;局部地区的降水极值呈减少趋势。