Fe(Ⅲ)微生物还原机理及其研究进展

厌氧异养型微生物还原Fe(Ⅲ)的同时可以氧化降解有机物,在污染环境修复中具有积极的作用.目前对Fe(Ⅲ)微生物还原的物理、生物化学特性的认识还十分有限.总结了近年来自然环境中Fe(Ⅲ)还原菌的单菌种分离情况和混合菌的降解作用,探讨了Fe(Ⅲ)还原以及有机物降解的机理,分析了Fe(Ⅲ)可能对微生物产生的抑制作用,并提出了进一步研究的方向.     

水泥对垃圾焚烧飞灰的固化处理试验研究

对垃圾焚烧飞灰的化学成分、重金属物质的含量及浸出浓度进行测试分析.结果表明,飞灰中Pb和Cr等重金属物质浸出量超过浸出毒性标准,因而被认为是危险废物,必须进行固化处理.还考察了水泥对焚烧飞灰中重金属物质固化的效果,研究表明当飞灰掺量适当时,重金属物质的固化效果良好.重金属物质通过物理固封、替代,沉淀反应和吸附等形式可固化进水泥水化产物结构中.     

城市产业水污染控制优化研究——以株洲市为例

针对城市产业水污染状况，应用产业结构和工业行业结构优化模型，试图找出城市产业结构调整方法。研究以株洲市为例，根据株洲市产业结构和行业结构特点对模型进行改进和最优化计算。计算结果表明，产业和行业生产用水的调整可以减少废水排放量和实现经济增长。在此基础上，提出了株洲市产业和行业凋整方案，以期实现城市经济发展与环境保护协调发雇。     

滇池底泥微生物菌群对微囊藻毒素的生物降解

采用滇池水华蓝藻中提取提纯的微囊藻毒素（microcystins，MCs）作为微生物生长的碳源和氮源，从长期暴露于蓝藻水华的滇池底泥中，通过从含低浓度到高浓度MCs的逐步培养驯化，获得了高效降解MCs的微生物混合菌群，在初始MC-RR和LR浓度大约分别为50mg／L和30mg／L下，3d内可将MCs全部降解。进一步活性研究显示，不同含碳和含氮化合物虽然能够促进混合微生物菌群的生长，但对降解MCs却无明显的促进作用，说明MCs既可以作为微生物生长的碳源，又可以作为微生物生长的氮源，在富含有机物的天然水体中并不一定能够促进微生物对MCs的生物降解。     

纤维素废弃物水热处理制H2的研究进展

水热处理为纤维素废弃物资源化应用开辟了一条新的途径，文中就水热处理技术的特点、水热条件下纤维素的降解过程进行了介绍，并着重综述了纤维素废弃物水热制H2方面的研究进展，同时对纤维素及其废弃物的水热处理和资源化研究前景进行了展望。     

底泥对河流的二次污染浅析

根据底冲中污染物质累积和释放过程和底泥对河流二次污染的机理,运用适用的模式和苏州河的实测资料,可得到二次污染ＢＯＤ和ＣＯＤ的年释放量,以及增加上覆河上的ＢＯＤ和ＣＯＤ浓度。由此认为,对于底泥污染严重的河流,疏浚是必不可少的,其目的在于清除或隔绝黑富集层上覆河上的二次污染。     

Impact of meteorology and energy structure on solvent extractable organic compounds of PM2.5 in Beijing, China

Twenty-eight PM2.5 samples collected in Summer (July 2002) and Winter (November 2002) at two sites in Beijing, China were analyzed using GC/MS to investigate the impact of meteorology and coal burning on the solvent extractable organic compounds (SEOC). The characteristics and abundance of the n-alkanes, polycyclic aromatic hydrocarbons (PAHs), n-fatty acids and n-alkanols were determined. Source identification was made using organic species as molecular markers. Semi-volatile compounds of alkanes and PAHs had much higher concentrations in winter than summer because of the large difference in the temperature between the seasons. Plant wax emission was a major contributor to n-alkanes in summer, but fossil fuel residue was a major source (>80%) in winter. The seasonal differences in the distribution of pentacyclic triterpanes clearly shows the impact of coal burning for space heating in winter. The yield of PAHs in winter (148 ng m(-3) at the urban site and 277 ng m(-3) at the suburban site) was six to eight times higher than that in summer and was found to be mainly from coal burning. Higher pollutant concentrations were measured at the suburban site than the urban site in winter due to the rapid expansion of the city limit and the relocation of factories from urban to suburban areas over the last two decades.     

Space-time modeling for the Missouri Turkey Hunting Survey

The Missouri Turkey Hunting Survey (MTHS) is a postseason mail survey conducted by the Missouri Department of Conservation. The 1996 MTHS provides information concerning the number of turkeys harvested by hunters on each day and the total number of trips made to the counties by these hunters on each day of the hunting season. The success rates are then found from this information. Small sample sizes produce large standard errors for the estimates at the county level. We use a Bayesian hierarchical generalized linear model to estimate daily hunting success rates at the county level. The model includes an autoregressive process for the days of the hunting season and spatially correlated random geographic effects. The computations are performed using Gibbs sampling and adaptive rejection sampling techniques. Results show that there are significant spatial corelations between counties and correlations between days of the hunting season. The estimates are close to the frequency estimates at the state level and much more stable at the county level.     

Diversity pattern and spatial scale: a study of a tropical rain forest of Malaysia

Scale is emerging as one of the critical problems in ecology because our perception of most ecological variables and processes depends upon the scale at which the variables are measured. A conclusion obtained at one scale may not be valid at another scale without sufficient knowledge of the scaling effect, which is also a source of misinterpretation for many ecological problems, such as the design of reserves in conservation biology.This paper attempts to study empirically how scaling may affect the spatial patterns of diversity (tree density, richness and Shannon diversity) that we may perceive in tropical forests, using as a test-case a 50 ha forest plot in Malaysia. The effect of scale on measurements of diversity patterns, the occurrence of rare species, the fractal dimension of diversity patterns, the spatial structure and the nearest-neighbour autocorrelation of diversity are addressed. The response of a variable to scale depends on the way it is measured and the way it is distributed in space.We conclude that, in general, the effect of scaling on measures of biological diversity is non-linear; heterogeneity increases with the size of the sampling units, and fine-scale information is lost at a broad scale. Our results should lead to a better understanding of how ecological variables and processes change over scale.     

深圳市观澜河流域水土流失规律研究

深圳市观澜河流域地处南亚热带,受自然因素和人为因素的影响,流域存在着严重的水土流失,改革开放以来,流域的大片土地被开发成了工业开发区。工业开发区在建设阶段,机械夷平土地所形成的各种松散的堆积坡,引起了新的水土流失类型。本文研究和探讨了该流域的水土流失规律及水土流失对流域水环境的影响。