邻菲哕啉分光光度法测定水中总铁的改进

对邻菲哕啉分光光度法测定水中总铁的方法进行了改进：采用50ml比色管水浴还原水样--分光光度计比色测定水中总铁。测试结果表明,改进法精密度和准确度均优于标准方法,是测定水中总铁较为理想的方法     

Is the availability of different nutrients a critical factor for the impact of bacteria on subterraneous carbon budgets?

Bacteria thriving in underground systems, such as karsts, adapt to use a variety of nutrients. Most of these nutrients derive from superficial processes. This study shows that bacteria are able to differentially induce carbonate precipitation or dissolution depending on the availability of nutrients for growth. Different bacterial strains isolated from caves, representing the most common components of these microbial communities, were cultured with different carbon and nitrogen sources (e.g., acetate, glucose, peptone, humic acids) and induced changes in pH were measured during growth. Carbonate can either precipitate or dissolve during bacterial growth. The induction of carbonate precipitates or their dissolution as a function of consumption of specific carbon sources revealed the existence of an active nutrient cycling process in karsts and links nutrients and environmental conditions to the existence of a highly significant carbon sink in subterraneous environments.     

厦门市酸雨分布特征与气象条件的关系分析

厦门市是我国酸雨控制区之一。文章利用1992～2005年厦门市的探空、降水量和酸雨资料来分析厦门市不同气象条件对降水酸度、酸雨出现率的影响,分析结果表明:(1)不同等级的降水对降水酸度和酸雨出现率有明显影响,相对于夏、秋二季,冬、春二季的降水酸度更酸,酸雨出现率更高。(2)K指数、850～700hPa层的冷暖平流对酸雨污染没有明显影响。(3)酸雨出现率随着1500m高空风速的增大而增多,风向变化对降水酸度和酸雨出现机率的影响不大。(4)逆温对酸雨污染的有一定的影响。     

大气污染总量控制GA方法中的多源模拟系统

大气污染总量控制的GA方法,是利用遗传算法(GA)的自适应全局搜索寻优功能,通过模拟的自然进化机制来求算经过全局优化的区域允许排放总量以及区域允许排放总量在区域内各污染源之间的分配方案的一种新的大气污染总量控制方法。在基于遗传算法的大气污染总量控制中,需要运用一个高效而可靠的大气污染多源模拟系统,以便根据源强分布快速计算出准确的浓度场。文章介绍了该大气污染多源模拟系统的设计与实现技术。     

悬浮液进样-AAS法测定TSP中锌、铅和铁的含量

用浓硝酸和高氯酸混酸体系在超声波作用下消解滤膜,加入稳定剂琼脂,用超声波震荡15min制成悬浮液,用火焰原子吸收光谱法测定TSP中的锌、铅和铁的含量,并以传统浓HNO3-H2O2湿法消解-原子吸收光谱法的测定结果为参考对测定值进行t检验,结果表明:RSD≤3.27%(n=6),两种方法的相对误差<±0.85%,且两种方法无显著性差异,说明悬浮液进样法的测定结果准确、可靠。     

丹江口水库总氮监测与综合分析

在优级化布点基础上对丹江口水库汉江子库总氮浓度进行监测与综合分析。近几年丹江口水库总氮浓度稳定,进一步下降趋势不明显,2008年全库区总氮浓度仍超过GB3838-2002Ⅲ类标准限值,在湖北省地表水环境监测网水库中相对较高。其中,丰水期最高,平水期最低,库尾最高,面积较大的库湾最低。来自河流的外源污染是汉库总氮超标主要原因,与上游水土流失、农业面源污染、工业和城镇生活污染有关。建议进一步加强库内和集水区综合污染防治,加强包括该库底质在内的环境监测。     

Evaluation of ambient air quality in Guangzhou, China

On the basis of the reported air quality index （API） and air pollutant monitoring data provided by the Guangzhou Environment Monitoring Stations over the last twenty-five years, the characteristics of air quality, prominent pollutants, and variation of the average annual concentrations of SOE, NOE, total suspended particulate （TSP）, fine particulates （PM10）, CO and dustfall in Guangzhou City were analyzed. Results showed that TSP was the prominent pollutant in the ambient air environment of Guangzhou City. Of the prominent pollutants, TSP accounted for nearly 62%, SOE 12.3%, and NOx 6.4%, respectively. The average API of Guangzhou over 6 years was higher than that of Beijing, Tianjin, Nanjing, Hangzhou, Suzhou and Shanghai, and lower than that of Shenzhen, Zhuhai and Shantou. Concentrations of air pollutants have shown a downward trend in recent years, but they are generally worse than ambient air quality standards for USA, Hong Kong and EU. SOE and NOx pollution were still serious, impling that waste gas pollution from all kinds of vehicles had become a significant problem for environmental protection in Guangzhou. The possible causes of worsening air quality were also discussed in this paper.     

Pollutant loads of surface runo inWuhan City Zoo, an urban tourist area

The pollutant loads of surface runoff in an urban tourist area have been investigated for two years in the Wuhan City Zoo, China. Eight sampling sites, including two woodlands, three animal yards, two roofs and one road, were selected for sampling and study. The results indicate that pollutants ranked in a predictable order of decreasing load （e.g. animal yard〉roof〉woodland〉road）, with animal yards acting as the key pollution source in the zoo. Pollutants were transported mainly by particulate form in runoff. Particulate nitrogen and particulate phosphorous accounted on average for 61%, 78% of total pollutant, respectively, over 13 monitored rainfall events. These results indicate the treatment practices should be implemented to improve particulate nutrient removal. Analysis of the M（V） curve indicate that no first flush effect existed in the surface runoff from pervious areas （e.g. woodland, animal ground yard）, whereas a first flush effect was evident in runoff from impervious surfaces （e.g. animal cement yard, roof, road）.     

A forest pathogen drives change in plant functional trait composition in the Southwest Australian Floristic Region

Plant functional traits weighted by cover-abundance have been used to measure change across a wide range of temperature, moisture and grazing gradients. We use this approach along a chronosequence of disease infestation (Phytophthora cinnamomi) in the species-diverse Banksia woodlands of the Southwest Australian Floristic Region (SWAFR). We compare the use of absolute (community-weighted totals-CWT) and relative cover data (community-weighted means-CWM) to demonstrate the importance of total cover change in reference to the Mass Ratio Hypothesis.Plant species cover-abundance was recorded along a space-for-time disease chronosequence, and functional trait data collected for the 48 dominant species from healthy vegetation. Six traits with deduced links to key ecosystem functions were measured for each species and values for two indices (CWT and CWM) compared along the disease chronosequence. Trait data was collected on plant height, growth form, specific leaf area, leaf dry matter content, root pattern and carbohydrate storage.Despite substantial shifts in individual species cover and a reduction in total species cover, the majority of CWM values did not change significantly following disease infestation. The use of relative cover-abundance data disregards important changes in total species cover, apparent from our comparative analysis. In contrast to CWMs, all CWT values were reduced following disease infestation, suggesting a potential reduction in productivity, reduced capacity as a carbon sink and altered site water balance. Verification of these potential changes in ecosystem functions is required using fine-scale quantitative techniques. The CWT index is complementary to traditional CWMs and useful when analysing changes in plant trait data where total species cover changes have been detected. In relation to P. cinnamomi infestation, shifts in CWT trait values indicate the ability of an introduced plant pathogen to have substantial indirect impacts beyond substantial floristic change.     

湖南某地采铀试验工程废水处理工艺设计

通过分析湖南境内某铀矿原地爆破浸出、地表堆浸采铀试验工程工艺流程以及该工程产生的废水源强及性质,介绍了BaCl2-Ca(OH)2中和沉淀法对该股废水处理的可行性及达到的效果。