川西南山区聚落宜居性的空间差异分析

结合山区实际情况,建立山区聚落宜居性评价指标体系。利用山区聚落宜居性评价模型对川西南山区26个区县进行系统评价,计算出川西南山区聚落宜居性指数。在此基础上通过ESDA分析和相关性分析,研究川西南山区聚落宜居性的空间差异,结果表明:（1）川西南山区聚落宜居性存在正的相关性,表现出很强的空间集聚特征;（2）在空间格局上,川西南山区聚落宜居性呈现东南-西北两极分化格局,并且以西昌、攀枝花、石棉为3个核心呈核心-边缘梯级结构模式特点;（3）H H空间关联模式集中连片分布在安宁河谷一带,L L空间关联模式集中连片分布于大小凉山一带,西昌、石棉呈现H L空间关联模式;（4）川西南山区聚落宜居性与自然环境宜居度、经济宜居度、社会宜居度均具有极显著的相关性     

基于力学平衡模型的乡村转型均衡发展判别方法研究

社会经济 生物自然 土地管理三维驱动因素通过“农村人口 耕地 农村居民点”3要素之间的相互联系与相互作用驱动着乡村转型发展。以该3要素为研究对象,提出基于力学平衡模型乡村转型发展偏离度的评价方法,并综合应用 2000 年和 2010 年两期 Landsat TM影像解译数据及2006~2020年规划修编数据,分析了江苏省乡村地区转型变化的特征规律。研究表明：江苏省各县（市区）乡村地区转型发展过程中,存在不同程度偏离发展情况;偏离度空间上呈现极角苏南<苏中<苏北,极径苏南>苏中>苏北的规律;农村居民点扩张成为乡村转型均衡发展的最重要阻碍因素,这根源于我国特殊的城乡“三元”结构社会体制,目前“生产空间较好的实现了转型,生活空间和身份空间依然滞留在乡村地区”,现阶段的乡村转型发展是一种不均衡的发展模式,必须实现向“以人为本”发展方式转变     

长江天鹅洲故道浮游动物群落结构及水质评价

于2011年4月~2012年1月按季度对长江天鹅洲故道浮游动物进行了采样调查。共检出浮游动物87种,其中原生动物22属38种,占总种类数的437%;轮虫25属36种,占总种类数的414%;枝角类8属9种,占总种类数的103%;桡足类4种,占总种类数的46%。浮游动物的年平均密度为25 7119 ind/L,以原生动物和轮虫为主,分别占总密度的937%和56%;年平均生物量为36 mg/L,以原生动物和枝角类为主,分别占总生物量的319%和281%。15种优势种中9种为富营养水体指示种。绿急游虫、双叉尾毛虫、长圆膜袋虫和小链巨头轮虫全年形成优势,而针簇多肢轮虫、缘板龟甲轮虫、角突臂尾轮虫在春、夏、秋季形成优势,螺形龟甲轮虫只在春秋形成优势。绿急游虫、双叉尾毛虫、长圆膜袋虫等富营养水体指示种在受污染较多的6和10号两处采样点数量较多。按现存量法和浮游动物优势种群法判定,天鹅洲故道属于富营养类型,与根据Shannon Weaver多样性指数和Pielou均匀度指数的评价为中污染水平的结果一致。同时对浮游动物种类组成小型化的形成原因进行了分析讨论     

射频加热强化土壤气相抽提技术的应用

热强化土壤气相抽提技术是一种高效的土壤治理技术,广泛应用于包气带土壤中挥发性有机污染物的去除。在天津某有机污染场地开展射频加热强化土壤气提技术应用研究,研究了射频阳极连接方式对场地加热效果的影响,并考察了该技术对实验场地的实际修复效果。结果表明,射频阳极采用并联方式连接对场地的加热效果较好,加热10 d后,场地温度升高约40℃;随着SVE系统工作时间的延长,场地温度逐渐下降,土壤气中TVOCs的浓度逐渐下降;经过约2个月的修复,中浅层土壤中污染物的总去除率约90%,氯仿去除率达95%,深层土壤中的污染物去除率约64%。     

纵向塞曼恒温平台石墨炉原子吸收法测定土壤,底质中镉和砷

为准确测定土壤中低含量元素镉和砷，研究了集恒温平台石墨炉（ＳＴＰＦ）一体的纵向塞曼效应背景校正，最大功率升温，钯作基体改进剂和吸收峰面积积分的最新分析方法。方法测定结果，镉和砷的检测限（３σ）分别为３５×１０－１３ｇ和５４×１０－１１ｇ；相对标准差（ｎ＝６）分别为４１％～５２％和２６％～４５％；回收率分别为８６５％～１０９％和９１２％～１０５％     

Enhanced nutrients removal from municipal wastewater through biological phosphorus removal followed by partial nitritation/anammox

Conventional biological removal of nitrogen and phosphorus is usually limited due to the lack of biodegradable carbon source, therefore, new methods are needed. In this study, a new alternative consisting of enhanced biological phosphorus removal (EBPR) followed by partial nitritationanammox (PN/A), is proposed to enhance nutrients removal from municipal wastewater. Research was carried out in a laboratory-scale system of combined two sequencing batch reactors (SBRs). In SBR1, phosphorus removal was achieved under an alternating anaerobic-aerobic condition and ammonium concentration stayed the same since nitrifiers were washed out from the reactor under short sludge retention time of 2–3 d. The remaining ammonium was further treated in SBR2 where PN/A was established by inoculation. A maximum of nitrogen removal rate of 0.12 kg N?m^–3?d^–1 was finally achieved. During the stable period, effluent concentrations of total phosphorus and total nitrogen were 0.25 and 10.8 mg?L^–1, respectively. This study suggests EBPR-PN/A process is feasible to enhance nutrients removal from municipal wastewater of low influent carbon source.

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A stochastic fuzzy chance-constrained programming model for energy–environment system planning and management in the City of Beijing

A stochastic and fuzzy chance-constrained programming (SFCCP) model was developed in this study for supporting energy–environment management in the city of Beijing, China. SFCCP was capable of tackling the variables in constraints as fuzzy random variables, which were integration of randomness and vagueness. SFCCP was applied to an energy–environment management system in the city of Beijing. The study results indicated that SFCCP was useful in helping decision makers gain in-depth insights into proposed management system and establish environment-friendly energy allocation alternatives. The application of SFCCP is expected to provide a good demonstration to energy–environment management problems under complex uncertainties.     

基于EFDC水动力-水质模型的建立--以慈湖河为例

本文根据马鞍山市慈湖河流域水环境现状,结合当地政府对慈湖河的管理整治目标,选择EFDC水动力-水质模型作为慈湖河水环境模型。并根据慈湖河流域整体情况对时间空间进行概化。时间概化上,最终确定水动力学模拟时间步长为10s,水质模拟时间步长为20s;空间概化上,采用凸四边形网格概化,各网格之间为一维线性关系;通过CAD、GIS软件,将河道划分为106个网格,共计86行、24列,建立二维模型。通过研究参考文献及相似案例,最终确定本模型的参数和取值。将参数值输入程序中,对慈湖河流域2013年水质进行模拟计算。与马鞍山实际数据比对后发现,模型输出的水位、流速、水质结果在合理范围内。表明在慈湖河干流建立二维水质污染扩散模型,具有较高的拟合、预测精度和泛化能力,模型及方法可为相关水质预测研究提供参考。此外该模型可与web应用系统集成,应用于水质预警,模拟不同污染负荷情形下水质变化,模拟污染事故发生后不同应急措施对污染情况的改善效果,为污染控制和水环境管理工作提供科学依据。     

The occurrence of synthetic musks in human breast milk in Sichuan, China

Human breast milk samples collected from mothers (n = 110) who lived in Chengdu, Sichuan Province, southwestern China in 2009 were analyzed to determine the concentrations of 13 musk compounds. Possible relationships between musk concentrations and some personal characteristics were also studied. Only five target analytes were detected in the milk samples analyzed, with median concentration values of 16.5, 11.5, 7.85, <1.5 and <1.4 ng g⁻¹ lipid weight for AHTN (7-acetyl-1,1,3,4,4,6-hexamethyl-1,2,3,4-tetrahydronaphthalene), HHCB (1,3,4,6,7,8-hexahydro-4,6,6,7,8,8-hexamethylcyclopenta[γ]-2-benzopyran), HHCB-lactone (1,3,4,6,7,8-hexahydro-4,6,6,7,8,8-hexamethylcyclopenta[γ]-2-benzopyran-1-one), OTNE ([1,2,3,4,5,6,7,8-octahydro-2,3,8,8-tetramethylnaphthalen-2yl]ethan-1-one) and musk ketone (4-tert-butyl-2,6-dimethyl-3,5-dinitroacetophenone, MK), respectively. Mothers who reported high use of hand-cleaning agents, body-cleaning agents, shampoo and hair conditioners, hair dyes and hair gels had significantly elevated milk concentrations of HHCB whereas elevated milk concentrations of AHTN were observed among mothers reporting high use of body-cleaning agents, body lotions, shampoos, hair dyes and hair gels. Younger age showed a significantly positive effect on milk concentrations of both HHCB and AHTN whereas BMI after delivery, the number of children nursed and place of residence (urban or rural) had no significant effect. The estimated median daily intakes of synthetic musks for breast-fed infants were considerably lower than the current provisional tolerable daily intake amounts suggested for adults.     

渤海和黄海北部地区海冰灾害风险评估

海冰灾害是中国海洋灾害的主要灾种之一。渤海和黄海北部地区由于受冬季风带来的寒潮天气影响成为中国最主要的结冰海域。基于灾害风险理论,将研究区海岸带上17个地级市的71个县区作为评价单元,对海冰灾害风险进行评估。选取冰期天数和最大冰厚2个指标,计算致灾因子危险度指数;选取涉海人口密度、海洋经济密度、海洋一产比重等3个指标,计算承灾体脆弱性指数;综合危险度指数与脆弱性指数计算各县区的海冰灾害风险指数,并绘制风险等级图。该风险等级图揭示了海冰灾害风险在渤海和黄海北部地区海岸带上的分布状况,为中国制定海冰灾害风险防范策略提供参考。