Estimation of Nonpoint Source Nitrate Concentrations in Indiana Rivers Based on Agricultural Drainage in the Watershed

Subsurface tile‐drained agricultural fields are known to be important contributors to nitrate in surface water in the Midwest, but the effect of these fields on nitrate at the watershed scale is difficult to quantify. Data for 25 watersheds monitored by the Indiana Department of Environmental Management and located near a U.S. Geological Survey stream gage were used to investigate the relationship between flow‐weighted mean concentration (FWMC) of nitrate‐N and the subsurface tile‐drained area (DA) of the watershed. The tile DA was estimated from soil drainage class, land use, and slope. Nitrate loads from point sources were estimated based on reported flows of major permitted facilities with mean nitrate‐N concentrations from published sources. Linear regression models exhibited a statistically significant relationship between annual/monthly nonpoint source (NPS) nitrate‐N and DA percentage. The annual model explained 71% of the variation in FWMC of nitrate‐N. The annual and monthly models were tested in 10 additional watersheds, most with absolute errors within 1 mg/l in the predicted FWMC. These models can be used to estimate NPS nitrate for unmonitored watersheds in similar areas, especially for drained agricultural areas where model performance was strongest, and to predict the nitrate reduction when various tile drainage management techniques are employed.     

西部地区SO_2总量控制方案合理性评估

通过新增工业产值、农用地面积、降雨强度和环保投资4个指标,引入信息熵对各指标进行权重分配,科学界定基尼系数合理性范围,构建了以改良基尼系数为度量标准的二氧化硫总量控制方案分配合理性的评价体系,并将其应用于"十二五"西部地区二氧化硫排放总量控制规划方案合理性评价工作中。研究结果表明,西部地区"十二五"SO2总量控制方案存在不合理,可优先考虑针对环保投资进行调整。     

基于“四元主体模型”的矿产资源开发生态补偿主体研究

生态补偿是矿产资源开发中迫切需要研究解决的问题,其关键是解决补偿主体缺位和研究补偿主体之间的相互关系.利用“四元主体模型”对我国矿产资源开发的生态补偿主体进行了研究.四元生态补偿主体是指矿产资源开发企业、矿产输入区、各级政府和民间环境保护组织.将矿产资源开发分为三个阶段进行研究,第一阶段是以政府为主导的开发前预防性补偿阶段,第二阶段是以企业为主导的开发中即时性补偿阶段,第三阶段是开采后的修复性补偿阶段.具体分析了矿产资源开发三个阶段的四元补偿主体变化过程及其主导补偿主体和辅助补偿主体的关系.     

青岛国际旅游市场时空变动特征分析——基于亲景度与竞争态模型

利用地理集中指数、年际集中指数、亲景度、竞争态等研究方法,对1995-2011年青岛国际入境旅游客源国市场的时空变化特征进行了分析.研究表明:①青岛国际客源国的G值平均为55.39,空间分布相对集中,市场结构相对单一;②各客源国年际集中指数差异性大,时间变化不尽相同;③亲景度差异显著,国际游客对青岛的偏爱度各具特点;④青岛客源国的整体市场竞争态的年际差异大,由“瘦狗市场”向“明星市场”演变.     

长江上游曲麻莱至玉树段春秋季浮游植物群落结构及多样性评价

于2012年春季（4月）和秋季（10月）对长江上游曲麻莱至玉树段的浮游植物进行初步研究。结果显示：浮游植物共3门62种（属），以硅藻门最多，42种（属），占678%，其次是绿藻门11种（属），占177%，蓝藻门9种（属），占145%。浮游植物优势种为普通等片藻（Diatoma vulgare）、长等片藻（Diatoma elongatum）、尖针杆藻（Synedra acus）、曲壳藻（Achnanthes sp）、舟形藻（Navicula sp）、桥弯藻（Cymbella sp）、脆杆藻（Fragilaria sp）、直链藻（Melosira sp）、异极藻（Gomphonem sp）、菱形藻（Hantzchia sp）、小环藻（Cyclotella sp）、小颤藻（Oscillatoria tenuis）、席藻（Phormidium sp）和小球藻（Chlorella sp）14种，其中硅藻门12种（属），占优势种类的786%。浮游植物种类组成的季节变化不明显，春季（4月）和秋季（10月）均以硅藻为优势种群。浮游植物平均数量3487×104 cells/L，平均生物量0138 8 mg/L，硅藻数量和生物量分别占8786%和9668%,为优势种群。浮游植物现存量表现为春季高于秋季，支流高于干流。Shannon Wiener指数平均值251，Pielou指数平均值070，Marggalef指数平均值089，Shannon Wiener指数、Pielou指数和Marggalef指数是秋季高于春季。结合浮游植物各项评价指标，得出长江上游曲麻莱至玉树段浮游植物群落结构比较稳定，种类分布较为均匀，水体属贫营养型，水域生态环境良好     

Oxidative stress and genotoxicity of 1-methyl-3-octylimidazolium chloride on loach (Misgurnus anguillicaudatus)

This study was a preliminary step to evaluate the acute toxicity of 1-methyl-3-octylimidazolium chloride ([C₈mim]Cl) on loach (Misgurnus anguillicaudatus) by determining the effects on hepatic antioxidant enzyme activities and by the comet assay. The results showed that [C₈mim]Cl had acute toxicity at concentrations above 20 mg L^?1, inducing oxidative stress and genotoxicity on fish liver cells. In respect to enzyme activities, [C₈mim]Cl induced changes in the activities of superoxide dismutase, catalase, and glutathione content the livers of fish exposed at 20–80 mg L^?1. [C₈mim]Cl at the same exposure level caused a remarkable increase in malondialdehyde level. The comet assay indicated that [C₈mim]Cl at 20–80 mg L^?1 induced genotoxicity in liver cells. With increased exposure concentration and time, the two comet parameters trailing rate and tail moment were significantly increased, with significant differences (P < 0.05) observed between control group and each treatment group. The present study shows that ionic liquids can be a threat to the health of aquatic organism when accidentally released to aquatic ecosystems.     

我国小型矿山的可持续发展战略

目前 ,我国小型矿山普遍存在着缺乏规划、设备简陋、工艺落后、管理和技术水平低、安全保障条件差、运销不畅以及职工素质低等问题 ,并由此造成的浪费资源、污染环境十分严重。当前 ,经济建设中 95%的能源和 80 %的原料依赖矿产资源供给 ,矿产资源探明的储量已显不足。进入 2 1世纪后 ,保证经济可持续发展的矿产资源更加不足 ,尤其是小型矿山要在 2 1世纪保持可持续发展成为一项非常艰巨的任务。     

河流型水源地源水有机物种类分布特性及其与消毒副产物关系

研究了不同水文期条件下长三角某典型河流型水源地源水有机物种类分布特性及其与消毒副产物关系。结果表明，该水源地源水有机污染特性呈现出丰水期>平水期>枯水期的特点，水体腐殖化程度依次降低。经树脂富集分离后水样溶解性有机物(DOM)各组分占总有机碳(DOC)的比例有所不同。丰水期：疏水性有机酸(HPO A,38%)>亲水性有机物(HPI,26%)>过渡亲水性有机酸(TPI A,16%)>疏水性有机中性物质(HPO N,12%)>过渡亲水性中性物质(TPI N,8%)；平水期：HPO A(32%)>HPO N(22%)>TPI A(20%)>HPI(18%)>TPI N(8%)；枯水期：HPO A(28%)>TPI A(24%)>HPO N(20%)>HPI(19%)>TPI N(9%)。DOM中仅HPI组分比紫外吸光度值(SUVA)低于原水，其余均高于原水，其中HPO A组分SUVA值最高，是原水的177倍。各水文期条件下，疏水性有机物（疏水性有机酸和疏水性中性物质）对三卤甲烷和卤乙酸生成的贡献，分别超过全部有机物氯化后消毒副产物生成量的60%和65%，表明疏水性有机物是最主要的消毒副产物前体物，应当作为水处理工艺重点去除的有机物组分。各水文期源水有机物特性与消毒副产物生成潜能的关系变化不大，三卤甲烷生成潜能(STHMFP)与SUVA的线性相关度较高，卤乙酸生成潜能(SHAAFP)与SUVA的线性相关度一般。因此，可用水样SUVA值间接反映三卤甲烷生成潜能，以利于在实际生产中快速监控水中消毒副产物前体物的变化趋势