Study of metabolites from the degradation of polycyclic aromatic hydrocarbons (PAHs) by bacterial consortium enriched from mangrove sediments

The PAH metabolites produced during degradation of fluorene, phenanthrene and pyrene by a bacterial consortium enriched from mangrove sediments were analyzed using the on-fiber silylation solid-phase microextraction (SPME) combining with gas chromatography–mass spectrometry (GC–MS) method. Seventeen metabolites at trace levels were identified in different PAH degradation cultures based on the full scan mass spectra. In fluorene degradation cultures, 1-, 2-, 3- and 9-hydroxyfluorene, fluorenone, and phthalic acid were detected. In phenanthrene and pyrene degradation cultures, various common metabolites such as phenanthrene and pyrene dihydrodiols, mono-hydroxy phenanthrene, dihydroxy pyrene, lactone and 4-hydroxyphenanthrene, methyl ester, and phthalic acid were found. The detection of various common and novel metabolites demonstrates that SPME combining with GC–MS is a quick and convenient method for identification as well as monitoring the real time changes of metabolite concentrations throughout the degradation processes. The knowledge of PAH metabolic pathways and kinetics within indigenous bacterial consortium enriched from mangrove sediments contributes to enhance the bioremediation efficiency of PAH in real environment.     

基于高通量分析方法的长江干流重庆段抗生素种类特征及来源初探

采用高通量分析方法对长江干流重庆段11个流域断面、2个市政污水处理厂进水和6个养殖场废水的潜在抗生素进行筛查,并结合抗生素使用调查探讨其来源。结果表明,(1)共检出83种抗生素,其中流域内检出36种,污水处理厂和养殖场废水中检出70种;磺胺间甲氧嘧啶检出率最高,在流域水体和废水的检出率分别为91%和55%,喹诺酮类是检出抗生素的主要类型;(2)长江干流重庆段下游检出抗生素数量高于上游检出抗生素;(3)有20种抗生素可能由上游携带和重庆市内排放2种方式进入流域,7种抗生素可能由上游携带入境,9种抗生素可能由重庆市内排放引入长江。     

The toxicity of cadmium ion (Cd2+) to phycocyanin: an in vitro spectroscopic study

Environmental Science and Pollution Research - The pollution of heavy metals is a severer problem for the ecosystems in waters. The toxicity of Cd2+ on phycocyanin (PC) is studied in molecular...     

Progress in the ecology and conservation of giant pandas

Giant panda (Ailuropoda melanoleuca) conservation is a possible success story in the making. If extinction of this iconic endangered species can be avoided, the species will become a showcase program for the Chinese government and its collaborators. We reviewed the major advancements in ecological science for the giant panda, examining how these advancements have contributed to panda conservation. Pandas’ morphological and behavioral adaptations to a diet of bamboo, which bear strong influence on movement ecology, have been well studied, providing knowledge to guide management actions ranging from reserve design to climate change mitigation. Foraging ecology has also provided essential information used in the creation of landscape models of panda habitat. Because habitat loss and fragmentation are major drivers of the panda population decline, efforts have been made to help identify core habitat areas, establish where habitat corridors are needed, and prioritize areas for protection and restoration. Thus, habitat models have provided guidance for the Chinese governments’ creation of 67 protected areas. Behavioral research has revealed a complex and efficient communication system and documented the need for protection of habitat that serves as a communication platform for bringing the sexes together for mating. Further research shows that den sites in old‐growth forests may be a limiting resource, indicating potential value in providing alternative den sites for rearing offspring. Advancements in molecular ecology have been revolutionary and have been applied to population census, determining population structure and genetic diversity, evaluating connectivity following habitat fragmentation, and understanding dispersal patterns. These advancements form a foundation for increasing the application of adaptive management approaches to move panda conservation forward more rapidly. Although the Chinese government has made great progress in setting aside protected areas, future emphasis will be improved management of pandas and their habitat.     

南雄优质适产烤烟因土施肥技术研究

采用田间试验方法,探明南雄县烟区三种土壤类型氮、磷、钾养分的供应特性,烤烟在各生育期吸收养分的规律,不同土壤类型氮、磷、钾肥的不同配比对烤烟产量和质量的影响。根据三年试验结果进行统计,提出优质适产烤烟因土施肥技术方法,为南雄烤烟生产的发展提供了科学的施肥依据。     

The performance of RAMS in representing the convective boundary layer structure in a very steep valley

Data from a comprehensive field study in the Riviera Valley of Southern Switzerland are used to investigate convective boundary layer structure in a steep valley and to evaluate wind and temperature fields, convective boundary layer height, and surface sensible heat fluxes as predicted by the mesoscale model RAMS. Current parameterizations of surface and boundary layer processes in RAMS, as well as in other mesoscale models, are based on scaling laws strictly valid only for flat topography and uniform land cover. Model evaluation is required to investigate whether this limits the applicability of RAMS in steep, inhomogeneous terrain. One clear-sky day with light synoptic winds is selected from the field study. Observed temperature structure across and along the valley is nearly homogeneous while wind structure is complex with a wind speed maximum on one side of the valley. Upvalley flows are not purely thermally driven and mechanical effects near the valley entrance also affect the wind structure. RAMS captured many of the observed boundary layer characteristics within the steep valley. The wind field, temperature structure, and convective boundary layer height in the valley are qualitatively simulated by RAMS, but the horizontal temperature structure across and along the valley is less homogeneous in the model than in the observations. The model reproduced the observed net radiation, except around sunset and sunrise when RAMS does not take into account the shadows cast by the surrounding topography. The observed sensible heat fluxes fall within the range of simulated values at grid points surrounding the measurement sites. Some of the scatter between observed and simulated turbulent sensible heat fluxes are due to sub-grid scale effects related to local topography.     

黄土高原沟坡地土地生产力评价的指标体系与评价方法

通过对渭北黄土高原地区沟坡地土壤理化性质的分析和对当地社会经济状况的调查研究,应用层次分析法对沟坡地土地自然生产力和现实生产力进行了分析和评价.在分析过程中,把当地主要造林树种根系垂直分布特征及其根系抗旱性特性纳入了分析评价体系.结果表明,嘴头村和西坡村不同树种沟坡地上刺槐(Robinia pseudoacacia)的自然生产力属于中等稍微偏上水平,而山杏(Prunus armeniacia var. ansu)、油松(Pinus tabulaeformis)和侧柏(Platycladus orientalis)的自然生产力水平则较低.两地沟坡地上的现实生产力计算结果则证明刺槐和山杏两个树种表现出了较高的水平,具有较好的发展前途;而油松和侧柏的现实生产力水平则较低,其发展推广受到了限制.群众对沟坡开发治理的态度和对开发方案的认可对沟坡开发的成功起到了重要作用.     

炼焦污水零排放技术初探

本文介绍了炼焦污水零排小试结果,试验中采用新型大孔吸附树脂脱酚,蒸汽汽提脱氨,处理后的污水用作熄焦补充水.试验证明该零排放方案是可行的.     

废水的生物脱氮除磷新工艺的设想

结合废水生物脱氮除磷机理和影响因素，在对几种典型脱氮除磷工艺氮、磷去除率进行比较的基础上，解析了一些典型工艺除氮除磷不足之处。根据重庆城市污水水质实际情况和地形的特点，设想一种新的生物脱 氮除磷工艺，从而弥补传统工艺的不足。可望提高系统的脱氮和除磷效率，达到更好的脱氮除磷的目的，减少对水体的污染。     

试论江西省环境监理稽查

分析了环境监理稽查的分类和内容，结合江西省面临的环境保护问题，阐述了加强环境监理稽查工作的必要性和紧迫性。