无机离子对左旋葡聚糖光降解的影响

左旋葡聚糖(LG)被广泛作为生物质燃烧的示踪剂.然而,近年来研究表明左旋葡聚糖在大气中不稳定而会发生光降解.此外,对于大气中含量较高的SO₄^2-、NO₃-、NO₂-无机离子对LG光解的影响罕有报到.为此,本文模拟了液相中SO₄^2-、NO₃-、NO₂-对LG光氧化行为的影响.结果表明,Na2SO₄、NaNO₃、NaNO₂条件下LG光解速率常数分别为0.208、0.182、0.165 min^-1,均低于对照组(0.266 min-1),这表明无机离子的存在会减缓LG光降解速率.此外,这3种无机离子对LG光解产物中的低分子脂肪酸分布,甲酸/乙酸(C1/C2)比率均有重要的影响.其中,SO₄^2-存在下产物中戊二酸较多、NO₃-存在下产物中甲酸较多、NO₂-存在下产物中乙酸较多;NO₂-存在下产物中的C1/C2比率小于1与一般二次源中的C1/C2比率不一致,这表明由单一反应引起的C1/C2并不总是大于1.这些结果对于我们深刻理解大气液相中的有机物转化具有重要的参考价值.     

福州大气污染对太阳辐射等要素的影响

福州大气污染对太阳辐射等要素的影响陈千盛（福建省气候中心，福州３５０００１）池艳珍（福建省气象局）关键词太阳总辐射；散射辐射；能见度混浊度因子．建国以来，福州由于市区范围不断扩大及工业发展，人口和车辆与日俱增，空中尘埃量随之增多，空气日益恶浊．这种状...     

Quantification of ammonia and hydrogen sulfide emitted from pig buildings in Korea

The aim of this field study was to determine the concentrations and emissions of ammonia and hydrogen sulfide in different types of pig buildings in Korea to allow objective comparison between pig housing types in Korea and other countries. Concentrations of ammonia and hydrogen sulfide in the pig buildings averaged 7.5ppm and 286.5ppb and ranged from 0.8 to 21.4ppm and from 45.8 to 1235ppb, respectively. The mean emissions of ammonia and hydrogen sulfide per pig (normalized to 75kg liveweight) and area (m2) from pig buildings were 250.2 and 37.8mg/h/pig and 336.3 and 50.9mg/h/m2, respectively. Ammonia and hydrogen sulfide concentrations and emissions were higher in the pig buildings managed with deep-pit manure systems with slats and mechanical ventilation than in other housing types.     

澳大利亚和新西兰自然生态和城市环境保护研究与借鉴

为学习和借鉴国外发达国家先进的生态和环境保护经验,研究了澳大利亚和新西兰自然生态和城市环境保护工作,分析了两国在自然生态保护、农业可持续发展、城市基础设施建设方面的特点,总结了两国在城市内河治理、挥发性气体回收、公众环保参与形式及固体废物回收利用等方面的经验,提出了中国生态与环境保护工作的建议。     

白洋淀表层沉积物元素的空间特征、风险评价及来源分析

对白洋淀流域表层沉积物中营养元素(N和P)、重金属(Pb、Cu、Zn、Cd、Cr、Co、Ni及Sn)及粒度进行研究,分析元素的空间变化并进行污染和风险评价,在此基础上结合河流的沉积特征,利用多元统计方法分析淀内沉积物元素的来源及其变化规律.结果表明,白洋淀和河流表层沉积物重金属平均含量均高于背景值,淀内空间上呈现营养元素"西北高东南低",重金属"中部高南北低"的特征;表层沉积物中元素综合污染指数(I)大小顺序为:Cd Pb Cr Cu=Zn Ni Sn Co,其中Cd为重度污染,其它重金属为中度污染,枣林庄地区Cr为重度污染;潜在生态危害系数(Eri)大小顺序为:Cd Pb Cu Cr Ni Zn,其中Cd除采蒲台地区具有强潜在生态风险,其他元素具有轻度潜在生态风险.淀内沉积物质地差异较小,流域河流入淀后的面源污染是影响白洋淀表层沉积物元素空间变化的主要原因,但淀内村庄的点源污染也不容忽视,尤其是元素N、P、Pb及Cr.     

Non-thermal plasma treatment of Radix aconiti wastewater generated by traditional Chinese medicine processing

The wastewater effluent from Radix aconiti processing, an important step in the production processes of traditional Chinese medicine (TCM), is a type of toxic wastewater and difficult to treat. Plasma oxidation methods have emerged as feasible techniques for effective decomposition of toxic organic pollutants. This study examined the performance of a plasma reactor operated in a dielectric barrier discharge (DBD) to degrade the effluent from R. aconiti processing. The effects of treatment time, discharge voltage, initial pH value and the feeding gas for the reactor on the degradation of this TCM wastewater were investigated. A bacterium bioluminescence assay was adopted in this study to test the toxicity of the TCM wastewater after non-thermal plasma treatment. The degradation ratio of the main toxic component was 87.77% after 60 min treatment with oxygen used as feed gas and it was 99.59% when the initial pH value was 8.0. High discharge voltage and alkaline solution environment were beneficial for improving the degradation ratio. The treatment process was found to be capable of reducing the toxicity of the wastewater to a low level or even render it non-toxic. These experimental results suggested that the DBD plasma method may be a competitive technology for primary decomposition of biologically undegradable toxic organic pollutants in TCM wastewater.     

若尔盖高原湿地生物多样性保护及其可持续利用

论述了川西北高寒湿地的自然概况及其形成原因,分析该区湿地的主要生物多样性价值,分布有具有世界意义的特有物种（黑颈鹤）和珍稀濒危物种,并且还分布有许多具有重要经济意义和具有科学研究价值的物种,但近几年来,人类活动的频繁干扰,如泥炭开采、过度放牧而破坏植被,再加上本区气候因素的特殊性,局部地区已引起沙化,使本区的生物多样性减少。由此而提出相应的生物多样性保护和可持续利用对策：协调人类活动与生物多样性保护的关系；严控载畜量,发展人工草场；发挥本地优势,利用泥炭治沙；建立湿地自然保护区；加强湿地立法     

水稻品种及典型土壤改良措施对稻米吸收镉的影响

水稻镉污染是我国当前重要的农产品安全问题,湖南攸县"镉大米"事件造成了严重的社会影响.针对南方酸性土壤镉污染特征,进行了"镉大米"治理技术研究.结果表明,当地主栽水稻品种株两优06的稻米Cd含量在大同桥和网岭镇的平均值分别为0.167 mg·kg-1和0.127 mg·kg-1,为其它品种的20%左右;石灰和矿物肥处理能够使稻米Cd含量降低到对照的20%~30%,覆膜处理使稻米Cd含量与对照相比降低约50%,而覆膜+生物炭+硅肥叶面肥处理能够降低80%左右,硅肥叶面肥单独施用及叶面肥和追肥配合施用能够显著降低稻米中的Cd含量90%以上;BCR法分析土壤Cd形态结果发现,供试大田土壤中Cd的弱酸可提取态比例较高,绝大多数样品达到55%以上,而施用石灰能够显著降低土壤中的弱酸可提取态和可还原态比例,增加残渣态比例,变化幅度达到20%左右;土壤Cd含量与p H值是影响稻米对Cd吸收的重要因素.