流域生态补偿机制研究

由于流域生态服务的公共物品属性,政府需要建立流域生态补偿机制以提供足够的流域生态报务。本研究提出流域生态补偿机制的主要模式是公共支付体系,财政转移支付体系,自发组织的私人协议和自由贸易体系。模式的决定要素是流域尺度和产投明晰程度,其组成要素是补偿标准,实际补偿量,组织实施和竞争机制的使用．     

催化铁内电解-生化法处理印染废水

纺织印染废水水质变化大、色度高,直接生物处理难度大.采用催化铁内电解法对浙江某地区的印染废水进行预处理,有效地去除了对生物有抑制的有机物,为后续的生化处理创造了有利条件,COD_Cr去除率达到85%;过去难以解决的色度问题也得到了有效的解决,可去除废水色度90%以上.另外,简要探讨了金属粒径,pH,温度等因素对去除有机物的影响.近40 d的连续流试验证明,内电解-生化工艺具有处理效果好、出水水质稳定、工艺设备简单、操作管理方便、能耗低等特点,是处理印染废水的有效方法之一.      

Lactic acid production with undefined mixed culture fermentation of potato peel waste

Potato peel waste (PPW) as zero value byproduct generated from food processing plant contains a large quantity of starch, non-starch polysaccharide, lignin, protein, and lipid. PPW as one promising carbon source can be managed and utilized to value added bioproducts through a simple fermentation process using undefined mixed cultures inoculated from wastewater treatment plant sludge. A series of non-pH controlled batch fermentations under different conditions such as pretreatment process, enzymatic hydrolysis, temperature, and solids loading were studied. Lactic acid (LA) was the major product, followed by acetic acid (AA) and ethanol under fermentation conditions without the presence of added hydrolytic enzymes. The maximum yields of LA, AA, and ethanol were respectively, 0.22 g g^?1, 0.06 g g^?1, and 0.05 g g^?1. The highest LA concentration of 14.7 g L^?1 was obtained from a bioreactor with initial solids loading of 60 g L^?1 at 35 °C.     

Enhanced removal of humic acid from micro-polluted source water in a surface discharge plasma system coupled with activated carbon

Surface discharge plasma (SDP) combined with activated carbon (AC) was employed to eliminate dissolved organic matter from micro-polluted source water, with humic acid (HA) as the model pollutant. Synergistic effect on HA removal was observed in the SDP-AC system; HA removal efficiency reached 60.9% within 5-min treatment in the SDP-AC system with 5.0 g AC addition, whereas 16.7 and 17.4% of HA were removed in sole SDP system and AC adsorption, respectively. Scanning electron microscope and Boehm titration analysis showed that chemical reactions between active species and functional groups of AC occurred. The existence of isopropanol or benzoquinone exhibited inhibitive effects on HA removal in the SDP system, while these inhibitive effects were weakened in the SDP-AC system. The influences of AC on ozone equivalent concentration and H₂O₂ concentration were evaluated, and there were approximately 39 and 20% decline in ozone equivalent concentration and H₂O₂ concentration within 6-min treatment in the SDP-AC system, respectively, compared with those in the sole SDP system. Dissolved organic carbon, specific ultraviolet absorbance, and UV absorption ratios analysis demonstrated that the SDP treatment destroyed the chromophoric groups, double bonds, and aromatic structure of HA molecules, and these destructive actions were strengthened by AC.     

Hydrochemical characteristics and identification of pollution ions of the springs in the south of Yanbian City,China

Environmental Geochemistry and Health - Mathematical statistics, correlation analysis, Piper and Gibbs diagrams, and geographic information system- based multi-criteria decision analysis were used...     

Bioaccessibility of heavy metals in soils cannot be predicted by a single model in two adjacent areas

Environmental Geochemistry and Health - The objective of this study was to examine whether a single model could be used to predict the bioaccessibility of heavy metals in soils in two adjacent...     

长江沿岸中心城市土地扩张时空演化特征——以宁汉渝3市为例

基于国家新型城镇化与"T"字型发展战略理论内涵,选取长江沿岸上、中、下游中心城市重庆、武汉和南京为实证研究对象,以1980、1990、2000、2010年4期遥感影像资料为基础数据源,通过RS、GIS和景观生态结合分析,分别对其城市扩张强度、城市扩张类型和城市建设用地扩张弹性进行对比分析,并采用景观指数进行了进一步分析和验证,从而系统分析了近30 a来3个城市建设用地扩张的时空特征与内在机理。结果表明:(1)30 a来,南京、武汉和重庆3市城市扩张强度均呈明显上升趋势,总体呈现南京市>武汉市>重庆市,但2000年是一个分水岭,之后重庆市城市扩张增速赶超武汉市,南京市反而增速最低;(2)对城市扩张类型分析表明,南京市始终以边缘式增长为主;武汉市在2000年之前以飞地式扩张主导,2000年之后呈现边缘式增长;重庆市以边缘式增长为主,但2000年之后飞地式增长迅速;(3)从城市建设用地扩张弹性分析表明,1980~2010年南京市土地扩张相比城市人口开始减缓,而武汉市和重庆市在2000年以后城市扩张速度远远超过城市人口增长速度;(4)景观指数验证分析结果显示,遥感分析、地理信息分析和景观生态分析的结合能够很好反映城市建设用地的扩张过程及演化特征。