山地城市灾害系统模糊风险评价

灾害风险是当前灾害研究的热点和核心之一。从灾害系统整体角度,厘定区域灾害系统风险,明晰灾害系统风险要素构成及其作用机制,对于科学指导区域综合防灾减灾具有重要意义。在山地城市灾害系统研究的基础上,基于"R=H×E×S/C"的灾害系统模糊风险概念模型,构建了反映山地城市灾害系统"致灾因子危险性、承灾体暴露性、灾损敏感性和防灾减灾能力"四个方面的"山地城市灾害系统模糊风险评价指标体系";提出了对山地城市灾害系统模糊风险进行定量评价与排序的"综合赋权(AHP-EVM)"二级模糊综合评判模型。在上述研究基础上,以重庆市38个区县作为研究对象,对理论模型进行了实证研究,并从整体上初步阐明和解释了山地城市(重庆市)38个区县的灾害系统模糊风险等级及成因。研究得出以下结论:(1)基于"综合赋权"模糊综合评判的"山地城市灾害系统模糊风险"评价结果科学、可靠,能够从整体反映山地城市灾害系统模糊风险水平及其构成。经过与灾情数据对比、专家评判,本研究所得评价结果通过验证,且与"模糊物元评价"所得结果基本一致。(2)重庆市灾害系统模糊风险整体水平居中。其中,渝中区、江北区,渝东北的城口县、奉节县以及渝东南的酉阳县,灾害系统风险等级高,各类灾害发生及造成损失的可能性较大,是未来防灾减灾工作的重点。     

过程耦合与空间集成：国土空间生态修复的景观生态学认知

新时期国土空间生态修复的核心是整体保护与系统治理,强调生态保护修复与社会经济发展耦合关联的系统性、协同性。景观生态学以景观为研究对象,基于整体综合视角聚焦景观结构与功能演变及其与人类社会相互作用机理,重点关注过程耦合与空间集成。面向国土空间生态修复的战略需求,景观生态学"格局与过程耦合—时空尺度—生态系统服务—景观可持续性"的研究路径能够为国土空间生态修复提供重要学科支撑;依据格局—过程互馈机理识别退化、受损的山水林田湖草生命共同体,基于景观多功能性权衡协调社会—生态需求并确定修复目标,应用生态安全格局优化多层级修复网络体系,建立面向景观可持续性的多尺度级联福祉保障。     

长沙城市景观破碎化空间异质性研究

景观破碎化表现为景观由单一、均质、连续趋于复杂、异化离散状态.空间异质性是空间景观格局产生的原因.不同尺度下景观破碎化空间异质性表现为不同的特征.遵循"尺度——格局——过程"的思路,以长沙市2005年、2010年遥感影像为数据源,针对都市区空间异质性对不同粒度和幅度水平的响应得到合适的分析尺度,进而对长沙市景观破碎化的空间格局和空间异质性展开研究,最后剖析了景观破碎化与城市生态系统的耦合过程.研究表明:(1)长沙都市区研究中,60 m粒度是一个本征观测尺度,1200 m幅度是理想特征尺度;(2)都市区景观破碎化空间格局复杂;(3)景观破碎化空间异质性受人为因素干扰影响大,随经济社会发展呈正相关关系.     

万州区滑坡灾害风险管理对策

滑坡灾害风险管理是实现滑坡灾害防灾减灾的有效途径。以三峡库区万州区为例,从分析万州区滑坡灾害风险管理的现状入手,总结了万州区滑坡灾害风险管理采取的主要手段和存在的问题,并有针对性地从区域和单体(单个灾害点)两个尺度,提出了万州区滑坡灾害风险管理的对策与建议,主要包括:在区域上,加强全区滑坡灾害点调查和监测工作、完善滑坡灾害应急预案、加强专业技术人员培训、优化各职能部门的组织结构及协助模式、建设风险动态管理系统、加大滑坡灾害风险控制投入、优化城市建设规划方案以及加强公众的教育和公共信息服务平台建议等;在单体上,加强监测系统建设、提高相关职能部门及民众对滑坡及其次生涌浪灾害的应急响应能力。     

漫话减灾保险学

风险是人类生存过程中不可避免的现象。无论从空间，还是时间上看，灾害和事故始终是存在的。保险就是对风险进行管理的一种有效方法，风险是保险赖以产生、发展的前提。减灾保险是灾害学与保险学的交叉学科，衡量风险的目的是为了选择适当的对付风险的办法。1灾害损失及保险尺度减灾与保险交叉有其历史渊源，从本世纪70年代以来，全球经济金融专家一直关注减灾业的发展。据美国保险协会统计，50年代自然灾害（进入统计的有洪水、风暴、地震、火山等）损失为494．5亿美元（1955年美元值），只占主要灾害21国GNP（国民总产值）总和的3．21…     

中国海岸带灾害地质查询及风险评价系统的设计与实现

介绍了"中国海岸带灾害地质查询及风险评价系统"开发研制的GIS平台,VB为二次开发工具,利用OLE技术集成开发.系统实现了对中国海岸带灾害地质的可视化查询、空间分析和综合评价,并为实施海岸带灾害地质综合管理和决策提供了科学依据.     

基于GIS的福建闽江上游山洪灾害风险区划

风险区划是山洪灾害的防治工作中的重要环节,在理解山洪灾害地域分异规律的基础上进行区划,可为科学地分析山洪灾害致灾因子,恰当地采取防治措施提供依据。以多年降水均值、土壤类型、坡度、高程、最长汇流路径长度、最长汇流路径比降、糙率、稳定下渗率、人口密度、地均GDP、土地利用状况和植被覆盖度12项因子,通过层次分析法与德尔菲法结合确定权重,进行空间叠加分析,完成闽江上游山洪灾害危险评价图、易损性图和山洪灾害风险区划图。并与1985—2013年近30年的灾害数据进行集成分析,比较山洪灾害风险区划与灾害发生情况,以期为不同风险地带的土地利用规划提供决策,为山洪易灾区居民提供风险信息。     

GIS技术在国内环境风险评价中的应用研究

环境风险评价是随着中国一系列环境污染事故频发和相应技术导则的出台而慢慢发展起来的一个新兴领域,学者结合GIS技术围绕环境风险评价也展开了多领域研究.论文综述了地理信息系统(GIS)技术在广义上的灾害风险、生态风险和狭义上的环境风险评价中的研究进展和应用现状.GIS技术支持下的灾害类和生态环境风险评价应用较多,但是与狭义上的环境风险评价结合较少,主要是应用GIS的空间分析功能进行综合分析.以后利用GIS强大的空间分析和数据处理的优势,与环境风险评价模型的关联和集成是研究的重点方向.     

生态系统服务与人类福祉耦合的空间格局及其驱动方式——以广州市为例

进入“人类世”新纪元,生态系统退化与人类需求提升间的矛盾日益加剧,可持续发展在此问题上的时代要义,就是要实现生态系统服务与人类福祉的科学协调。提出“从级联到耦合”的生态系统服务与人类福祉关系研究新思路,以广州市为研究对象,分析二者耦合关系的发展阶段及其空间分异,构建了耦合逻辑框架,通过典型耦合类型区来辨析其驱动方式差异,为新时代快速城镇化地区的人地协调提供实践参考。结果发现:(1)广州市生态系统服务价值严重萎缩,受到人类福祉趋同化增进的胁迫,二者的耦合协调性差;(2)耦合关系以生态系统服务为刚性主导,服务低值区的连片蔓延促成了低失调的同化格局,服务供给与福祉需求之间呈现出显著的空间失衡;(3)通过资本流动、土地利用、尺度效应、利益分配等驱动方式差异,生态系统服务与人类福祉形成了发展阶段和供需匹配各异的耦合关系,主要包含空间争夺的低失调、空间弱关联的拮抗和空间互促的高协调。据此,亟需以生态文明与高质量发展为导向,严格保护生态空间,提升城镇空间的发展质量,统筹人地系统综合管理,弱化用地权衡和空间博弈,加强供需耦合的空间协同,促进人与自然和谐共生。     

基于心理距离的公众台风灾害风险感知比较分析——以湛江市和珠海市为例

台风是广东省沿海地区最严重的自然灾害。基于心理距离,以公众灾害风险感知为主线,通过比较湛江市和珠海市两地居民在心理距离六个维度上的差异,并分析两地居民的灾害风险可接受性,从而反映心理距离对公众台风灾害风险感知的综合影响。研究结果表明:除了概率距离外,湛江居民对台风灾害风险感知的时间距离、空间距离、情绪距离、人际距离皆比珠海居民远,在信息距离上两地居民差异不大。根据灾害风险可接受性评价方法计算得出,湛江居民的台风灾害风险可接受性大于珠海居民。因此,公众感知台风灾害风险的心理距离越远,灾害可接受风险水平越高。     

Toxic effects of acetochlor, methamidophos and their combination on nifH gene in soil

Toxic effects of two agrochemicals on nifH gene in agricultural black soil were investigated using denaturing gradient gel electrophoresis （DGGE） and sequencing approaches in a microcosm experiment. Changes of soil nifH gene diversity and composition were examined following the application of acetochlor, methamidophos and their combination. Acetochlor reduced the nifH gene diversity （both in gene richness and diversity index values） and caused changes in the nifH gene composition. The effects of acetochlor on nifH gene were strengthened as the concentration of acetochlor increased. Cluster analysis of DGGE banding patterns showed that nifH gene composition which had been affected by low concentration of acetochlor （50 mg/kg） recovered firstly. Methamidophos reduced nifH gene richness that except at 4 weeks. The medium concentration of methamidophos （150 mg/kg） caused the most apparent changes in nifH gene diversity at the first week while the high concentration of methamidophos （250 mg/kg） produced prominent effects on nifH gene diversity in the following weeks. Cluster analysis showed that minimal changes of nifH gene composition were found at 1 week and maximal changes at 4 weeks. Toxic effects of acetochlor and methamidophos combination on nifH gene were also apparent. Different nifH genes （bands） responded differently to the impact of agrochemicals： four individual bands were eliminated by the application of the agrochemicals, five bands became predominant by the stimulation of the agrochemicals, and four bands showed strong resistance to the influence of the agrochemicals. Fifteen prominent bands were partially sequenced, yielding 15 different nifH sequences, which were used for phylogenetic reconstructions. All sequences were affiliated with the alpha- and beta-proteobacteria, showing higher similarity to eight different diazotrophic genera.     

Arsenic uptake by arbuscular mycorrhizal maize （Zea mays L.） grown in an arsenic-contaminated soil with added phosphorus

The effects of arbuscular mycorrhizal (AM) fungus (Glomus mosseae) and phosphorus (P) addition (100 mg/kg soil) on arsenic (As) uptake by maize plants (Zea mays L.) from an As-contaminated soil were examined in a glasshouse experiment.Non-mycorrhizal and zero-P addition controls were included.Plant biomass and concentrations and uptake of As,P,and other nutrients,AM colonization,root lengths,and hyphal length densities were determined.The results indicated that addition of P significantly inhibited root colonization and development of extraradical mycelium.Root length and dry weight both increased markedly with mycorrhizal colonization under the zero-P treatments,but shoot and root biomass of AM plants was depressed by P application.AM fungal inoculation decreased shoot As concentrations when no P was added,and shoot and root As concentrations of AM plants increased 2.6 and 1.4 times with P addition,respectively.Shoot and root uptake of P,Mn,Cu,and Zn increased,but shoot Fe uptake decreased by 44.6%,with inoculation, when P was added.P addition reduced shoot P,Fe,Mn,Cu,and Zn uptake of AM plants,but increased root Fe and Mn uptake of the nonmycorrhizal ones.AM colonization therefore appeared to enhance plant tolerance to As in low P soil,and have some potential for the phytostabilization of As-contaminated soil,however,P application may introduce additional environmental risk by increasing soil As mobility.     

Degradation of metabolites accumulated of benzo[a]pyrene by coupling Penicillium Chrysogenum with KMnO4

Several main metabolites of benzo[a]pyrene （BaP） formed by Penicillium chrysogenum, Benzo[a]pyrene-1,6-quinone （BP 1,6- quinone）, trans-7,8-dihydroxy-7,8-dihydrobenzo[a]pyrene （BP 7,8-diol）, 3-hydroxybenzo[a]pyrene （3-OHBP）, were identified by high-performance liquid chromatography （HPLC）. The three metabolites were liable to be accumulated and were hardly further metabolized because of their toxicity to microorganisms. However, their further degradation was essential for the complete degradation of BaP. To enhance their degradation, two methods, degradation by coupling Penicillium chrysogenum with KMnO4 and degradation only by Penicillium chrysogenum, were compared; Meanwhile, the parameters of degradation in the superior method were optimized. The results showed that （1） the method of coupling Penicillium chrysogenum with KMnO4 was better and was the first method to be used in the degradation of BaP and its metabolites; （2） the metabolite, BP 1,6-quinone was the most liable to be accumulated in pure cultures; （3） the effect of degradation was the best when the concentration of KMnO4 in the cultures was 0.01% （w/v）, concentration of the three compounds was 5 mg/L and pH was 6.2. Based on the experimental results, a novel concept with regard to the bioremediation of BaP-contaminated environment was discussed, considering the influence on environmental toxicity of the accumulated metabolites.     

Impact of atrazine and nitrogen fertilizers on the sorption of chlorotoluron in soil and model sorbents

Sorption of chlorotoluron in ammonium sulfate, urea and atrazine multi-solutes system was investigated by batch experiments. The results showed application of nitrogen fertilizers to the soil could affect the behavior of chlorotoluron. At the same concentration of N, sorption of chlorotoluron decreased as the concentration of atrazine increased on the day 0 and 6 in soil, respectively. The sorption of chlorotoluron increased from 0 to 6 d when soils were preincubated with deionized water, ammonium sulfate and urea solution for 6 d. That indicated incubation time was one of the most important factors for the sorption of chlorotoluron in nitrogen fertilizers treatments. The individual sorption isotherms of chlorotoluron in rubbery polymer and silica were strictly linear in single solute system, but there were competition sorption between pesticides or between pesticides and nitrogen fertilizers. That indicated the sorption taken place by concurrent solid-phase dissolution mechanism and sorption on the interface of water-organic matter or water-mineral matter.     

Potential of plant polyphenol oxidases in the decolorization and removal of textile and non-textile dyes

In this study an effort has been made to use plant polyphenol oxidases; potato （Solanum tuberosum） and brinjal （Solanum melongena）, for the treatment of various important dyes used in textile and other industries. The ammonium sulphate fractionated enzyme preparations were used to treat a number of dyes under various experimental conditions. Majority of the treated dyes were maximally decolorized at pH 3.0. Some of the dyes were quickly decolorized whereas others were marginally decolorized. The initial first hour was sufficient for the maximum decolorization of dyes. The rate of decolorization was quite slow on long treatment of dyes. Enhancement in the dye decolorization was noticed on increasing the concentration of enzymes. The complex mixtures of dyes were treated with both preparations of polyphenol oxidases in the buffers of varying pH values. Potato polyphenol oxidase was significantly more effective in decolorizing the dyes to higher extent as compared to the enzyme obtained from brinjal polyphenol oxidase. Decolorization of dyes and their mixtures, followed by the formation of an insoluble precipitate, which could be easily removed simply by centrifugation.     

Removal of heavy metals from sewage sludge by low costing chemical method and recycling in agriculture

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Isolation and preliminary characterization of a 3-chlorobenzoate degrading bacteria

A study was conducted to compare the diversity of 2-, 3-, and 4-chlorobenzoate degraders in two pristine soils and one contaminated sewage sludge. These samples contained strikingly different populations of mono-chlorobenzoate degraders. Although fewer cultures were isolated in the uncontaminated soils than contaminated one, the ability of microbial populations to mineralize chlorobenzoate was widespread. The 3- and 4-chlorobenzoate degraders were more diverse than the 2-chlorobenzoate degraders. One of the strains isolated from the sewage sludge was obtained. Based on its phenotype, chemotaxonomic properties and 16S rRNA gene, the organism S-7 was classified as Rhodococcus erythropolis. The strain can grow at temperature from 4 to 37℃. It can utilize several （halo）aromatic compounds. Moreover, strain S-7 can grow and use 3-chlorobenzoate as sole carbon source in a temperatures range of 10-30℃ with stoichiometric release of chloride ions. The psychrotolerant ability was significant for bioremediation in low temperature regions. Catechol and chlorocatechol 1,2-dioxygenase activities were present in cell free extracts of the strain, but no （chloro）catechol 2,3- dioxygenase activities was detected. Spectral conversion assays with extracts from R. erythropolis S-7 showed accumulation of a compound with a similar UV spectrum as chloro-cis,cis-muconate from 3-chlorobenzoate. On the basis of these results, we proposed that S-7 degraded 3-chlorobenzoate through the modified ortho-cleave pathway.     

Single and joint effects of pesticides and mercury on soil urease

The influence of two pesticides including chlorimuron-ethyl and furadan and mercury （Hg） on urease activity in 4 soils （meadow burozem and phaeozem） was investigated. The soils were exposed to various concentrations of the two pesticides and Hg individually and simultaneously. Results showed that there was a close relationship between urease activity and organic matter content in soil. Chlorimuron-ethyl and furadan could both activate urease in the 4 soils. The maximum increment of urease activity by chlorimuronethyl was up to 14%-18%. There was almost an equal increase （up to 13%-21%） in the urease activity by furadan. On the contrary, Hg markedly inhibited soil urease activity. A logarithmic equation was used to describe the relationship （P〈0.05） between the concentration of Hg and the activity of soil urease in the 4 tested soils. Semi-effect dose （ED50） values by the stress of Hg based on the inhibition of soil urease in the 4 soils were 88, 5.5, 24 and 20 mg/kg, respectively, according to the calculation of the corresponding equations. The interactive effect of chlorimuron-ethyl or furadan with metal Hg on soil urease was mainly synergic at the highest tested concentrations.     

Organochlorine pesticides in soils under different land usage in the Taihu Lake region, China

A field study was conducted in the Taihu Lake region, China in 2004 to reveal the organochlorine pesticide concentrations in soils after the ban of these substances in the year 1983. Thirteen organochlorine pesticides (OCPs) were analyzed in soils from paddy field, tree land and fallow land. Total organochlorine pesticide residues were higher in agricultural soils than in uncultivated fallow land soils. Among all the pesticides, ΣDDX (DDD, DDE and DDT) had the highest concentration for all the soil samples, ranging from 3.10 ng/g to 166.55 ng/g with a mean value of 57.04 ng/g and followed by ΣHCH, ranging from 0.73 ng/g to 60.97 ng/g with a mean value of 24.06 ng/g. Dieldrin, endrin, HCB and α-endosulfan were also found in soils with less than 15 ng/g. Ratios of p,p'-(DDD DDE)/DDT in soils under three land usages were: paddy field ＞ tree land ＞ fallow land, indicating that land usage inlfuenced the degradation of DDT in soils. Ratios of p,p'-(DDD DDE)/DDT ＞1, showing aged residues of DDTs in soils of the Taihu Lake region. The results were discussed with data from a former study that showed very low actual concentrations of HCH and DDT in soils in the Taihu Lake region, but according to the chemical half-lives and their concentrations in soils in 1980s, the concentration of DDT in soils seemed to be underestimated. In any case our data show that the ban on the use of HCH and DDT resulted in a tremendous reduction of these pesticide residues in soils, but there are still high amounts of pesticide residues in soils, which need more remediation processes.     

Alterations of organ histopathology and metallolhionein mRNA expression in silver barb, Puntius gonionotus during subchronic cadmium exposure

Common silver barb,Puntius gonionotus,exposed to the nominal concentration of 0.06 mg/L Cd for 60 d,were assessed for histopathological alterations(gills,liver and kidney),metal accumulation,and metallothionein(MT)mRNA expression.Fish exhibited pathological symptoms such as hypertrophy and hyperplasia of primary and secondary gill lamellae,vacuolization in hepatocytes,and prominent tubular and glomerular damage in the kidney.In addition,kidney accumulated the highest content of cadmium,more than gills and liver.Expression of MT mRNA was increased in both liver and kidney of treated fish.Hepatic MT levels remained high after fish were removed to Cd-free water.In contrast,MT expression in kidney was peaked after 28 d of treatment and drastically dropped when fish were removed to Cd-free water.The high concentrations of Cd in hepatic tissues indicated an accumulation site or permanent damage on this tissue.