Grazing greatly reduces the temporal stability of soil cellulolytic fungal community in a steppe on the Tibetan Plateau

Excessive livestock grazing degrades grasslands ecosystem stability and sustainability by reducing soil organic matter and plant productivity. However, the effects of grazing on soil cellulolytic fungi, an important indicator of the degradation process for soil organic matter, remain less well understood. Using T-RFLP and sequencing methods, we investigated the effects of grazing on the temporal changes of cellulolytic fungal abundance and community structure in dry steppe soils during the growing months from May to September, on the Tibetan Plateau using T-RFLP and sequencing methods. The results demonstrated that the abundance of soil cellulolytic fungi under grazing treatment changed significantly from month to month, and was positively correlated with dissolved organic carbon (DOC) and soil temperature, but negatively correlated with soil pH. Contrastingly, cellulolytic fungal abundance did not change within the fencing treatment (ungrazed conditions). Cellulolytic fungal community structure changed significantly in the growing months in grazed soils, but did not change in fenced soils. Grazing played a key role in determining the community structure of soil cellulolytic fungi by explaining 8.1% of the variation, while pH and DOC explained 4.1% and 4.0%, respectively. Phylogenetically, the cellulolytic fungi were primarily affiliated with Ascomycota (69.65% in relative abundance) and Basidiomycota (30.35%). Therefore, grazing substantially reduced the stability of soil cellulolytic fungal abundance and community structure, as compared with the fencing treatment. Our finding provides a new insight into the responses of organic matter-decomposing microbes for grassland managements.     

燃煤电厂烟气氮氧化物排放控制技术发展现状

在广泛查阅文献的基础上,对近年来国内外已成功应用和正在研究开发的一些主要的燃煤烟气氮氧化物控制技术进行了介绍。结合我国目前脱硝行业整体水平和国家环保政策要求,对我国脱硝行业技术研发方向提出了建议。     

公众太湖蓝藻水华生态风险感知特征研究——以无锡市区为例

蓝藻水华暴发已成为全球性生态环境问题。太湖作为流域重要的水源地,2007年蓝藻水华事件的暴发引起公众的高度关注。运用问卷调查法,研究无锡市区489名公众的太湖蓝藻水华生态风险感知特征及其主要影响因素。研究结果表明：蓝藻水华生态风险被公众知觉为总体风险是陌生和完全可控的;蓝藻水华暴发原因是陌生和不可控的,这是引起公众风险意识的主要因素。影响公众蓝藻水华生态风险感知水平的主要因素有媒体、信息和个体因素。报纸广播电视是主要的媒体因素。信息因素有灾害信息、灾害治理信息、政府防范措施信息。灾害治理信息的影响作用最大,其次是灾害信息和政府防范措施信息。不同性别、年龄段、教育程度、收入水平及职业的人群,对不同类别的风险信息关注程度不同,影响到个体风险偏好的不同。研究结果有助于决策者更全面地理解蓝藻水华风险的本质,开展风险沟通,针对不同特征的人群选择有效的风险管理方案。〖     

蚯蚓与污水土地处理试验研究

本研究将蚯蚓－－土壤床作为污水处理的一种试验装置。试验对蚯蚓的耐水能力，蚯蚓负荷、污水浓度以及渗滤速度等因素对污水处理效果的影响了初步研究，结果表明：采用合理的间歇运行引养殖污水土地处理是可行的，系统的去除率随渗滤速度的增加而降低；蚯蚓的存在能提高土壤对氮的吸附能力，提高污水处理脱氧效果。     

钻井泥浆和消油剂对合浦珠母贝的急性毒性效应

采用96h急性毒性试验配合滤食率和微核检测等方法，比较了石油勘探开发用3种钻井泥浆和3种消油剂对合浦珠母贝成贝急性毒性效应。实验结果表明：3种钻井泥浆对合浦珠母贝的半致死浓度均大于10^5mg/L；3种消油剂的半致死浓度分别为1047、5011和2630mg/L；滤食率与钻井泥浆和消油剂的浓度呈负相关；微核细胞率则与之呈正相关。     

论环境质量管理在线监控指挥系统建设

本文着重阐述在原有的“污染源在线监控系统”的基础上，通过架构更高层次的“环境质量管理在线监控指挥系统”，在环境监察行政执法上突破原有的“运动式”执法和宏观表面管理，实现在环境监察行政执法上的“点对点”数字化精确管理与在线指挥，在环境质量管理上突破原有的人工行政审批制，实现“以人为本”的环境质量管理电子政务行政许可制，以及由此带来环境质量管理理念、管理机制和环境监察行政执法工作模式的创新。提高行政效能，服务经济建设。     

Temporal and Spatial Variability of Water Supply Stress in the Haihe River Basin,Northern China1

Ji, Yuhe, Liding Chen, and Ranhao Sun, 2012. Temporal and Spatial Variability of Water Supply Stress in the Haihe River Basin, Northern China. Journal of the American Water Resources Association (JAWRA) 48(5): 999‐1007. DOI: 10.1111/j.1752‐1688.2012.00671.x Abstract: Water resources are becoming increasingly stressed under the influence of climate change and population growth in the Haihe River Basin, Northern China. Assessing the temporal and spatial variability of water supply stress is urgently needed to mitigate water crisis caused by water resource reallocation. Water supply and use data were compiled for the time period of 1998‐2003 in this synthesis study. The Water Supply Stress Index (WSSI) as defined as Water Demand/Water Supply was used to quantitate whether water supply could meet the demand of human activities across the study region. We found a large spatial gradient of water supply stress in the study region, being much higher in the eastern subbasins (ranging from 2.56 to 4.31) than the west subbasins (ranging from 0.56 to 1.92). The eastern plain region not only suffered more serious water supply stress but also had a much higher interannual variability than the western hilly region. The uneven spatial distribution of water supply stress might result from the distribution of land use, population, and climate. Future climate change and rapid economic development are likely to aggravate the existing water crisis in the study region.     

宜兴市清源污水处理厂升级改造工艺设计

宜兴市清源污水处理厂升级改造工程设计规模5×104m3/d,采用强化生物脱氮、机械微过滤(盘片过滤)工艺,利用现有池容进行内部改造,同时增加深度处理设施,提高出水标准,改造后出水ρ(COD)、ρ(BOD5)、ρ(SS)、ρ(NH3-N)、ρ(TN)和ρ(TP)平均值分别为34,6,5,1.3,10.3和0.36mg/L,各项水质指标均达GB18918-2002《城镇污水处理厂污染物排放标准》一级A标准。     

区域性安全生产风险影响因素及其权重确定研究

影响地区安全生产风险的因素众多,使得评价地区安全生产风险的控制水平极为复杂.系统分析地区安全生产风险的影响因素,并确定其权重,对提高区域性定量风险评价的科学性,有效实施区域安全生产风险管理具有重要意义.本文针对我国安全生产监督管理特点,对我国当前安全生产风险的多源化趋势进行了分析,提出了安全生产责任制、安全管理组织机构、安全生产法规、安全生产投入、安全科学技术等12个影响安全生产风险的核心因素,采用层次分析法(AHP)确定了安全生产风险影响因素的权重值,并设计了安全生产风险控制因子,以表征地区的安全生产风险控制水平.计算结果表明,安全生产规划、安全生产控制指标、安全生产法规和安全管理组织机构对地区安全生产风险的影响程度最高.