基于改进CM的尾矿坝体变形4级预警阈值确定方法*

为改善我国尾矿库在线监测系统由于重建设、轻利用而导致的事故预警能力被制约的现状，以尾矿坝体变形速率监测指标为研究对象，通过引入改进云模型，根据3E规则确定尾矿坝变形监测的正常运营值边界，建立尾矿库坝体变形速率4级预警阈值确定模型，以湖北省某尾矿库为例进行实例分析。结果表明:通过提出的坝体预警阈值确定方法，可得出尾矿库坝体变形速率黄、橙、红各级预警阀值分别为10.842，16.68，25.02 mm/d；进一步与典型小概率法计算结果对比表明，所提出的尾矿坝变形速率4级预警阈值确定方法更加科学合理，可用于尾矿库重要安全监测指标预警值的确定。     

围场县农田典型药物和个人护理品污染特征与生态风险预评价

利用超声萃取-固相萃取-高效液相色谱/串联质谱(LC-MS/MS)技术,对围场县全县农田中5个大类(磺胺类、四环素类、氟喹诺酮类、大环内酯类以及其他类)25种典型药物和个人护理品(PPCPs)的污染水平进行了调查,并采用风险熵法对其进行生态风险预评价。结果表明:有23种目标PPCPs被检出,不同目标物检出率差异显著,检出含量范围为0.38~6.50μg·kg-1,单种污染物最高检出浓度为101.9μg·kg-1(磺胺甲恶唑)。以目标物划分,分别有7种和5种被检出物质达到生态高风险和中等风险水平;以采样区域划分,41个土壤点位中分别有17个和12个达到生态高风险和中等风险水平。畜用PPCPs是围场农田中PPCPs污染物的主要来源,兽药滥用、粪便自然堆沤等传统农耕模式有造成农田土壤中PPCPs累积的趋势,因此需严控PPCPs污染源头,并推进畜禽粪便安全的资源化利用,以减缓农田土壤中由于PPCPs污染带来的潜在生态风险,保障围场地区生态环境功能、农田环境质量以及农产品安全品质。     

Water pollution footprints induced by industrial import and export in China

With the rapid development of foreign trade in China, industrial import and export has been an absolute subject in recent years. The huge trade surplus of import and export trade of industrial products brings not only high profits, but also pollution costs as well. Based on the concept of water pollution footprints (WPFs), this study applies the input-output method and calculates pollutant-producing coefficients of 20 major industrial sectors in China and investigates the WPFs caused by the import and export trades of these industrial sectors. The research results show that WPF resulting from exports exceeds that of imports from 2011 to 2015 in China. The net inflow of pollution footprint is mainly from paper mills, printing and stationery manufacturing, and textile industry; whereas a great number of WPFs are transferred to other countries by these sectors, such as metal mining and dressing industry and oil and natural gas exploitation industry.     

Expression and functional analysis of three nicosulfuron-degrading enzymes from Bacillus subtilis YB1

To investigate the degradation activity of the manganese ABC transporter, vegetative catalase 1 and acetoin dehydrogenase E1 from Bacillus subtilis YB1, the proteins were prokaryotically expressed and purified. Assay results showed that the three enzymes were able to degrade nicosulfuron (2- (4,6-dimethoxypyrimidine-2-pyrimidinylcarbamoylaminosulfonyl) -N,N-dimethylnicotinamide), with vegetative catalase 1 exhibiting the highest activity. To further examine the degradation pathway, the degradation products of the three enzymes and the YB1 strain were detected by liquid chromatography-mass spectrometry(LC-MS). The nicosulfuron degradation products of the three enzymes were consistent with those of the YB1 strain, indicating the presence of two pathways: one due to cleavage of sulfonylurea bridges and ring-opening of 1-(4,6-dimethoxy-pyrimidin-2-yl)-3-(2-methyliminomethanesulfonyl-acetyl)-ureaas the pyrimidine ring, yielding the product; and the another due to cleavage of a sulfonylurea bridge, yielding 4,6-dihydroxy pyrimidine (111 m/z), 2-ylamine ?4,6-dimethoxy pyrimidine and ((4-(dimethycarbamoyl)pyridine-2-yl)sulfonyl)carbamic acid as products, which were further degraded to 4,6-dihydroxy pyrimidine and N,N-dimethyl-2-sulfamoyl-isonicotinamide. The above results reveal a major contribution of extracellular enzymes to the degradation of nicosulfuron by the YB1 strain. Our data help in elucidation of the mechanism of nicosulfuron bio-degradation and may facilitate the construction of engineered strains.     

尾矿库伴生放射性污染清除水平估算研究

通过RESRAD程序模拟估算了某尾矿库伴生放射性污染清除水平,同时对尾矿库中的232 Th模拟估算参数进行设定,并对剂量约束限值的确定、照射情景分析、照射途径设定、模式参数设定、计算机模拟估算清除水平及估算结果分析等进行了分析研究。结果表明,此尾矿库中232 Th及其长寿命子体所致最大年有效剂量约为10.7mSv/a,超出了预设的0.25mSv/a的剂量约束限值;致癌风险0.023 5,远超出人们的可接受水平;当在剂量约束限值为0.25mSv/a时,此尾矿库土壤中的232 Th清除水平为0.047Bq/g。通过分析表明,该尾矿库开放前,必须采取一定措施,进行清除工作。     

组合式水生植物净化系统对Cu、Pb和Cd的去除与生物富集特征

选取再力花、美人蕉、水烛、旱伞草、梭鱼草、慈姑、菖蒲、水葫芦和大藻9种植物作为实验植物，构建成以高效净化重金属污染水体为主要功能的组合式水生植物高效净化系统（人工湿地＋生态浮床＋水生植物塘3个处理单元串联而成），研究不同处理单元中水生植物对重金属Cu、Pb和cd的去除能力及富集特征。结果表明，该净化系统经过为期60d的连续运行，对Cu、Pb和Cd的去除率较为稳定，可分别达到Cu93．5％～96．1％、Ph94．5％～95．2％和Cd95．6％～97．4％，3种重金属出水浓度均可达到GB3838-2002Ⅲ类水排放要求；其中人工湿地单元对重金属去除贡献率最高，Cu、Pb和Cd分别为54．15％、33．61％和44．84％，其次为生态浮床处理单元，Cu、Pb和Cd的去除贡献率分别为38．61％、51．42％和38．56％，而水生植物塘主要起到深度处理作用，对Cu、Pb和cd的去除贡献率分别为7．24％、14．97％和16．6％。9种植物在系统运行期间，生长状况良好，且重金属累积量较高，尤其是生物塘系统中的水葫芦和大藻，实验期间其重金属生物富集系数（BCF）均在200以上。所选植物不同部位对3种重金属的吸收富集能力均表现为根最强。     

组合式水生植物净化系统对Cu、Pb和Cd的去除与生物富集特征

选取再力花、美人蕉、水烛、旱伞草、梭鱼草、慈姑、菖蒲、水葫芦和大薸9种植物作为实验植物,构建成以高效净化重金属污染水体为主要功能的组合式水生植物高效净化系统(人工湿地+生态浮床+水生植物塘3个处理单元串联而成),研究不同处理单元中水生植物对重金属Cu、Pb和Cd的去除能力及富集特征。结果表明,该净化系统经过为期60 d的连续运行,对Cu、Pb和Cd的去除率较为稳定,可分别达到Cu 93.5%~96.1%、Pb 94.5%~95.2%和Cd 95.6%~97.4%,3种重金属出水浓度均可达到GB3838-2002Ⅲ类水排放要求;其中人工湿地单元对重金属去除贡献率最高,Cu、Pb和Cd分别为54.15%、33.61%和44.84%,其次为生态浮床处理单元,Cu、Pb和Cd的去除贡献率分别为38.61%、51.42%和38.56%,而水生植物塘主要起到深度处理作用,对Cu、Pb和Cd的去除贡献率分别为7.24%、14.97%和16.6%。9种植物在系统运行期间,生长状况良好,且重金属累积量较高,尤其是生物塘系统中的水葫芦和大薸,实验期间其重金属生物富集系数(BCF)均在200以上。所选植物不同部位对3种重金属的吸收富集能力均表现为根最强。     

再生水回用循环冷却系统药剂HJ-01阻垢机理

针对再生水回用于循环冷却系统中引起的结垢问题,进行了碳酸钙沉积实验和旋转挂片腐蚀实验,对所得的结垢产物的微观形态、元素组成以及化合物构成,分别采用扫描电子显微镜、X射线能谱仪和X射线衍射仪进行分析,探究复配药剂HJ-01在阻垢过程中的机理,并深入分析该药剂结构中官能团的阻垢特性。实验结果表明,药剂HJ-01可以通过在挂片表面形成具有保护作用的薄膜而阻垢,其阻垢机理包括晶格畸变、螯合增溶和分散作用;其中膦酸基(—PO3H2)和羟基(—OH)官能团引起晶格畸变作用;羧基(—COOH)官能团引起螯合增溶作用;而阻垢剂中的链状结构导致分散作用的产生。     

生态产品市场化实现路径及二元价格体系

本文从微观经济学角度阐释生态产品的市场化实现路径及其价格机制。认为生态产品市场化路径的前提是存在有形的,能够体现劳动价值,可交换的产品实体。鉴于现有研究所讨论的生态产品价值的体现皆源于各环境要素的支撑,因此可将清洁的水、空气、土壤等优质环境要素凝练为生态产品的基本有形载体。在此基础上,本文指出政府提供生态产品的有效路径有三条:创造、维系改善及修复。其中修复路径是现阶段市场化的优先选择方式。通过结合现阶段我国新的环保商业化模式——合同环境服务这一新命题,本文构建了生态产品合同环境服务政府采购的有效市场化路径,即政府通过绩效合同采购第三方环保服务,以综合环境目标为合同标的,通过所采购的一体化环境修复项目实现提供良好的生态产品。在此基础上围绕生态产品价格组成,本文提出生态产品的二元价格体系:指出生态产品买入与卖出的不同经济行为对应着生态环境的保护与开发两种对立的发展模式,这两种市场行为的外部性存在正负两种情景。综合考虑生产资料所有者属性,本文创新性地提出生态产品市场交易应采用买入-卖出二元价格体系。买入价格也称保护价格,主要考虑生产成本与利润,生产成本即生态修复项目的费用支出,其中利润是购买者(政府)予以产品生产者(提供修复服务的环保服务商)适当的利润空间,作为该生产者经济行为正外部性的补贴;出让价格也称牺牲价格,包括生产成本、社会成本(外部性成本)、生产资料成本、利润等,其中出让行为价格组成中的社会成本获益是政府,应主要用于支付环境管理成本。值得注意的是,在二元价格体系中,学者们讨论的生态产品价值与买入价格相关性不大,在数值或更接近出让价格。     

Greenhouse gas emissions from landfill leachate treatment plants: A comparison of young and aged landfill

With limited assessment, leachate treatment of a specified landfill is considered to be a significant source of greenhouse gas (GHG) emissions. In our study, the cumulative GHG emitted from the storage ponds and process configurations that manage fresh or aged landfill leachate were investigated. Our results showed that strong CH₄ emissions were observed from the fresh leachate storage pond, with the fluxes values (2219–26,489 mg C m^?2 h^?1) extremely higher than those of N₂O (0.028–0.41 mg N m^?2 h^?1). In contrast, the emission values for both CH₄ and N₂O were low for the aged leachate tank. N₂O emissions became dominant once the leachate entered the treatment plants of both systems, accounting for 8–12% of the removal of N-species gases. Per capita, the N₂O emission based on both leachate treatment systems was estimated to be 7.99 g N₂O–N capita^?1 yr^?1. An increase of 80% in N₂O emissions was observed when the bioreactor pH decreased by approximately 1 pH unit. The vast majority of carbon was removed in the form of CO₂, with a small portion as CH₄ (<0.3%) during both treatment processes. The cumulative GHG emissions for fresh leachate storage ponds, fresh leachate treatment system and aged leachate treatment system were 19.10, 10.62 and 3.63 Gg CO₂ eq yr^?1, respectively, for a total that could be transformed to 9.09 kg CO₂ eq capita^?1 yr^?1.