中国反刍动物甲烷排放量的初步估算及减缓技术

根据ＯＥＣＤ提供的反刍动物甲烷排放量计算方法，结合中国反刍动物能量供应的特点，初步估算了中国反刍动物甲烷排放量。反刍动物摄入总能量的６．９％～７．５％通过甲烷排放而损失掉，１９９０年甲烷排放量为５．８０Ｔｇ，约为全球动物排放量的７．２％。文中提出采取秸秆处理，舔砖和过瘤蛋白使用，改善管理等改进措施，不仅可以提高生产水平，也可减少甲烷排放量。     

Distribution of quinolone and macrolide resistance genes and their co-occurrence with heavy metal resistance genes in vegetable soils with long-term application of manure

The spread of antibiotic resistant bacteria (ARB) and antibiotic resistance genes (ARGs) has become an increasingly serious global public health issue. This study investigated the distribution characteristics and influencing factors of ARB and ARGs in greenhouse vegetable soils with long-term application of manure. Five typical ARGs, four heavy metal resistance genes (MRGs), and two mobile genetic elements (MGEs) were quantified by real-time quantitative polymerase chain reaction (qPCR). The amount of ARB in manure-improved soil greatly exceeded that in control soil, and the bacterial resistance rate decreased significantly with increases in antibiotic concentrations. In addition, the resistance rate of ARB to enrofloxacin (ENR) was lower than that of tylosin (TYL). Real-time qPCR results showed that long-term application of manure enhanced the relative abundance of ARGs in vegetable soils, and the content and proportion of quinolone resistance genes were higher than those of macrolide resistance genes. Redundancy analysis (RDA) showed that qepA and qnrS significantly correlated with total and available amounts of Cu and Zn, highlighting that certain heavy metals can influence persistence of ARGs. Integrase gene intI1 correlated significantly with the relative abundance of qepA, qnrS, and ermF, suggesting that intI1 played an important role in the horizontal transfer of ARGs. Furthermore, there was a weakly but not significantly positive correlation between specific detected MRGs and ARGs and MGEs. The results of this study enhance understanding the potential for increasing ARGs in manure-applied soil, assessing ecological risk and reducing the spread of ARGs.

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广西涠洲岛沉凝灰岩土壤粘粒矿物的研究

用X射线衍射分析和电子显微镜分析,对涠洲岛沉凝灰岩母质发育土壤的两个典型剖面八个土样的粘粒矿物进行分析研究。结果表明,离火山口距离不同的两个剖面土壤粘粒矿物组成不同,1号剖面以2:1型粘粒矿物为主,2号剖面则以1:1型粘粒矿物为主;结合其它分析结果,讨论了两个剖面土壤粘粒矿物组成不同的原因、对土壤有关特性的影响及其与土壤形成和分类的关系。     

Bioleaching of spent Ni-Cd batteries and phylogenetic analysis of an acidophilic strain in acidified sludge

Biohydrometallurgy is a novel method to recycle discarded batteries, in which sewage sludge is used as microorganisms and culture due to the presence of indigenous Thiobacilli. A two-step continuous flow leaching system consisting of an acidifying reactor and a leaching reactor was introduced to achieve the bioleaching of spent nickel-cadmium (Ni-Cd) batteries. The acid supernatant produced in the acidifying reactor by the microorganisms with ferrous ions as the substrate was conducted into the leaching reactor to dissolve electrode materials. The efficiency of a batch treatment of batteries was examined. The results showed that the complete dissolution of two AA-sized Ni-Cd batteries with 0.6 L/d acid supernatant took about 30, 20, and 35 days for Ni, Cd, and Co, respectively. But the dissolution ability of the three metals was different. Cd and Co can be leached mostly for pH below 4.0 while the complete dissolution of Ni can be achieved for pH below 2.5. Meanwhile, a strain (named Thiooxidans. WL) accounting for the reduction of pH in the acidified sludge was isolated and sequenced. It was identified to be 100% similar to Acidithiobacillus ferrooxidans strain Tf-49 based on 16S rDNA sequence analysis. The relevant phylogenetic tree constructed indicates that the strain should be classified into genus Acidithiobacillus ferrooxidans.     

介孔纳米TiO2的超声化学法合成及其表征

采用超声化学法制备介孔TiO2，并采用XRD，TEM，FT-IR等方法对样品进行了表征．结果表明，在超声波作用下，液相体系中能够一步合成锐钛矿相TiO2；添加有机模板剂并控制实验条件，则能直接合成具有介孔结构的锐钛矿相TiO2．超声化学法能更好地控制粒子的形貌和尺寸，所制备的TiO2晶型完整，孔径均匀，分散性好．     

城市大气污染治理规划方法

本文介绍了用于治理发展中国家城市大气污染的规划方法。它通过对城市大气污染的现状进行定量分析，确定主要污染分担源。用基础削减量、平权削减量、源强和经济优化削减量综合确定城市削减排放总量以及分配排放量的削减方案和筹集削减排放量的经费。     

传统生存方式变迁对农村环境的影响

随着农村社会经济的发展,农户的生存方式开始逐步由传统的生存方式逐步转变为现代的生存方式。在具体的案例研究过程中,我们既可以看到传统生存方式的环境友好的一面,也可以看到传统生存方式变迁过程中农户经济行为变化对于农村环境的不利影响。与此同时,社会经济发展过程中,新的现代生产生活要素的介入,在不断使农户的生活逐步走向现代化的同时,也带来了种种环境问题。总之,农村环境问题的产生既有传统生存方式本身存在的问题,也来自于生存方式变迁过程中新的外部物质的介入,因此,对于农村环境的改善需要同时从这两方面着手,在改善农户生存方式的同时,更要从根本上控制外部的污染物质的介入。     

Why does environmental compliance cost more than penalty?

In the environmental protection field of China, due to “lower law-breaking cost but higher law-abiding cost”, it is a common case that the enterprise chooses to break through the law on purpose. The punishment to the unlawful practices by the law directly decides the law-breaking cost of the enterprise, furthermore, influences the willingness to abide by the law and the trend to break through the law. The law-breaking cost of enterprises is jointly decided by the administrative liability, civil liability and criminal liability. However, in China, the enterprises breaking through the law are mainly penalized for the administrative liabilities, focusing less on the civil compensation liability on the environmental damage and criminal liabilities on the environmental crimes. Nevertheless, a complete environmental liability system is composed by administrative punishment, civil compensation and criminal sanction, none of which is dispensable. Therefore, the three layers defense could be established on punishing and deterring the environmental law-breakers. Considering all three aspects, administrative liability, civil liability and criminal liability, this paper analyzes the systemic disadvantages of the current environmental administrative punishment, civil compensation and criminal sanction in China, and investigates the legitimate reasons for the higher law-abiding cost compared with the law-breaking cost, and it is finalized with the measures and suggestions to solve this problem.     

Residues of organochlorinated pesticides in eggs of water birds from Tai Lake in China

The levels of organochlorine compounds in eggs of water birds from the colony on Tai Lake in China were studied. The eggs were collected in 2000 and belonged to the following species: 65 samples of black-crowned night heron (Nycticorax nycticorax), 36 samples of little egret (Egretta garzetta), 26 samples of cattle egret (Bubulcus ibis) from 13 clutches and 43 samples of Chinese pond heron (Ardeola bacchus) from 17 clutches. Dichlorodiphenyltrichloroethane (DDT) and its derivates (DDE and DDD), hexachlorocyclohexane (HCH) and its isomers (alpha-HCH, beta-HCH, gamma-HCH, delta-HCH), heptachlor, heptachlor epoxide, aldrin, dieldrin, endrin, endrin aldehyde, alpha-endosulfan, beta-endosulfan, and endosulfan sulfate were determined in the laboratory by gas chromatography. The data showed that DDE had the highest levels in all the samples, followed by beta-HCH. The mean levels of DDE among the water bird species were in the order as follows: black-crowned night heron (5464.26 ng/g, dry weight) > Chinese pond heron (2791.12 ng/g, dry weight) > little egret (1979.97 ng/g, dry weight) > cattle egret (660.11 ng/g, dry weight). DDT and its metabolites accounted for 90% of the total organochlorines, except that it was only 73% for cattle egret. The differences of the residue among the bird species were statistically significant and could be attributed to their variations in prey and habitat. Although the DDE burdens in Tai Lake were much lower than 8 microg/g (wet weight) which are thought to have significant adverse effects on black-crowned night herons, they would be expected to increase the risk of adverse effects on survival of chicks of herons and egrets, particularly black-crowned night heron, based on the critical value of 1 microg/g (wet weight) DDE. The burdens of HCHs in this study were higher and the cyclodienes were lower than those found elsewhere.     

拾荒者:边缘化的回收终端

背着一个麻袋,或是骑着一辆挂着蛇皮袋的自行车,整日穿行在城市的街头巷尾,收购各种有用生活废品,或是在各式各样的垃圾桶里搜寻各种有用的垃圾.他们,被人们称为“收破烂的”,也叫“拾荒者”。