珠江口沿岸土地利用变化及其地表热环境遥感分析

以遥感和GIS为技术手段,选择四期TM/ETM＋影像为数据源,对珠江口沿岸区域的土地利用及其地表热环境的变化进行了定量分析。1990—2008年期间,建设用地扩展是珠江口区域土地利用变化最为显著的特征,建设用地从1990年的605.50km^2增加到2008年的2394.26km^2。土地利用变化导致区域热环境效应增强,并促使不同土地利用类型在7个热力区间中的组成发生变化。珠江口东岸建设用地在数量上的优势使得珠江口的热力重心始终分布在东岸。研究结果表明,以建设用地扩展为突出特征的土地利用变化,深刻影响着区域热环境。     

Pollution characteristics of volatile organic compounds in the atmosphere of Haicang District in Xiamen City, Southeast China

The compositions, spatial distributions, seasonal variations and ozone formation potential (OFP) of volatile organic compounds (VOCs) were investigated in the atmosphere of Haicang District, Xiamen City, Southeast China. Twenty-four types of VOCs were measured in this study, and ethanol, methylene chloride, toluene, ethyl acetate and isopropyl alcohol were the abundant species based on concentration rank. The concentrations of total VOCs (TVOCs) in industrial areas were higher than those in residential and administrative areas and background site. For industrial areas, the TVOCs concentrations in summer were higher than those in winter, which might result from higher emissions from industrial activities because of stronger evaporation in summer. In contrast, non-industrial areas showed higher concentrations in winter due to the unfavorable meteorological conditions. The spatial distribution of BTEX (benzene, toluene, ethylbenzene and xylene) followed the order of industrial areas > residential and administrative areas > background site, and the concentrations in summer were lower than those in winter for most sites. The high ratios (8.9-14.0) of T/B in this study indicated that industrial emissions were the main sources in this district. X/B ratios were used to assess the ages of air parcels and provided evidence of the transport of air parcels among these sites. Total OFP (TOFP) showed the trend of increase with the increase of TVOCs, and toluene was found as the major contributor to TOFP.     

基于生态足迹服务价值法的生态承载力时空演化

为了客观地评价生态承载力及其时空演化规律，通过构建以价值量为单位的生态足迹-服务价值法的生态承载力分析框架，选取2000~2015年陕西省97个区县的面板数据，运用全局Moran’s I、LISA集聚图和空间杜宾模型等方法，分析了陕西省生态承载力指数的分布特征、演化路径及驱动因素。研究表明：（1）陕西省及三大地区生态承载力指数先快速升高后缓慢降低，存在显著的空间自相关和空间异质性，低值集聚现象明显，且向关中地区集中。（2）林地面积和当量因子价值是促进生态承载力指数提高的主要因素，人均消费价值是抑制生态承载力指数提升的主要因素。（3）影响陕北、关中和陕南地区生态承载力指数的驱动因素存在差异。因此，陕西省需要加大生态修复工程投入力度，减缓人均消费价值增长速度，实施差异化的生态承载力政策，以达到改善生态承载力的目标。     

Distribution and inventories of fallout radionuclides (239+240Pu, 137Cs) and 210Pb to study the filling velocity of salt marshes in Doñana National Park (Spain)

Within an extensive multinational and multidisciplinary project carried out in Do?ana National Park (Spain) to investigate its preservation and regeneration, the filling velocity of the salt marshes has been evaluated through the calculation of their average sediment accumulation rates. (239+240)Pu and (137)Cs from weapons testing fallout and total (210)Pb distribution profiles and inventories have been determined in some of the most characteristic zones of the park, namely, the ponds (or "lucios") and the waterjets (or "ca?os"). Plutonium inventories range from 16 to 101 Bq m(-2), (137)Cs values fluctuate between 514 and 3,758 Bq m(-2) and unsupported (210)Pb values comprise between 124 and 9398 Bq m(-2). Average sedimentation rates range from 3 to 5 mm y(-1) (1952-2002). These data are higher than those obtained by carbon dating for the period 6,500 AD-present, estimated as 1.5-2 mm y(-1), suggesting an increase in the accumulation of sediments and the alteration of the park's hydrodynamics caused by the re-channeling of the major rivers feeding the salt marshes.     

大同盆地地方氟病地区土壤中氟的赋存形态研究

以大同盆地地方氟病地区土壤为研究对象,采用连续化学提取法逐级提取土壤中水溶态、离子交换态、铁锰结合态、有机束缚态和残余态的氟,研究了大同盆地土壤中氟的赋存形态特征以及控制土壤中氟赋存形态的因素,进而探讨了土壤中氟氧化物迁移与转化对大同盆地高氟地下水形成的影响。结果表明:研究区土壤中氟的5种赋存形态按含量大小呈现出残余态氟水溶态氟交换态氟有机束缚态氟铁锰结合态氟的分布规律;相关分析显示水溶态氟与铁锰结合态氟呈现正相关性,离子交换态氟与有机束缚态氟和铁锰结合态氟呈现显著正相关性;大同盆地土壤中氟的背景值较高(545.29mg/kg),并在一定条件下各种形态的氟相互转化,可提供更多自由态的氟进入地下水中,从而形成高氟地下水。     

中国农村生态环境问题及对策

党的"十八大"报告提出了全民共圆"最美中国梦"。农村是生态文明建设的重要领域,加强农村环保是"三农"工作的重点和难点。农村污染排放已占中国"半壁江山",全面提升农村生态文明建设水平,是"最美中国梦"最重要的组成部分。本文研究了我国农村环境污染的整体现状及产生原因,并在此基础上提出相应对策。     

Validating the effects of the environmental regulation compliance scale: evidence from the Nigerian oil and gas industry

Environmental Science and Pollution Research - Growing environmental deterioration has caused many countries to tighten their environmental regulations across the globe. Recent studies show that...     

Exposure characteristics of phthalate metabolites among the Zunyi cohort of pregnant women in Southwest China

Environmental Science and Pollution Research - Reported evidence has increasingly indicated that exposure to phthalates can cause adverse pregnancy outcomes. However, phthalate exposure levels...