鲁东山区流域景观格局与面源污染关联关系

基于实地监测和3S技术,以鲁东低山丘陵地区栖霞市为研究区,采用Spearman相关、非约束性PCA、对应典范分析（CCA）等方法,研究不同流域尺度下景观格局与面源污染的关联关系。结果表明：（1）研究区景观格局空间分异明显,在特征尺度下农用地和建设用地斑块较为破碎,林地、园地斑块聚集性强。（2）研究区河流面源污染物主要以TN为主,EC、COD污染次之,主河道出水口为污染较为严重的区域。（3）景观格局对水质的影响丰水期要大于平水期,TN和EC对土地利用类型面积比例和景观格局指数的变化最为敏感。（4）平水期河岸带尺度下景观格局对TN影响最大的为斑块密度,EC受景观边缘密度影响最大,小流域尺度TN受景观蔓延度影响最大,COD与景观多样性关系密切;丰水期河岸带尺度景观多样性对TN影响最大,EC受斑块聚合度影响最大,小流域尺度影响TN最大的因素与平水期一致,EC与景观蔓延度关系密切。（5）小流域景观类型水平下,TN主要受林地斑块密度影响,TP与耕地散布与并列指数关系密切;丰水期TN受林地散布与并列指数影响显著,TP对林地平均分维数变化敏感,EC受草地聚集性影响最大。本文分析了研究区景观格局与面源污染空间分布特征,探讨了两者在不同尺度下的相关性,可为栖霞市水土资源可持续利用提供科学依据。     

东太湖水产养殖对沉积物中氨氧化原核生物的影响

本研究旨在了解东太湖水产养殖区表层沉积物中氨氧化微生物的群落特征.以编码氨单加氧酶的α亚基(amo A)基因为标记,通过实时荧光定量PCR技术(real-time q PCR)分析环境中好氧氨氧化原核生物的丰度;通过构建克隆文库、测序,进而划分操作分类单元(OTUs)构建系统发育树,分析氨氧化微生物的群落结构与多样性.分析养殖区和对照区表层沉积物中氨氧化微生物群落结构和多样性发现,养殖区中氨氧化细菌(ammonia-oxidizing bacteria,AOB)的丰度更高而对照区中氨氧化古菌(ammonia-oxidizing archaea,AOA)的丰度更高;AOA在养殖区多样性更高,AOB在对照区多样性更高;AOA在养殖区和对照区沉积物中的优势类群均为Nitrosopumilus,AOB在养殖区和对照区沉积物中的优势类群相同均为亚硝化螺旋菌属(Nitrosospira).水产养殖主要通过影响沉积物中的氨氮含量来影响AOA和AOB的丰度,养殖过程会影响AOA的群落结构而对AOB的群落结构则无明显影响.     

Seasonal variations of polybrominated flame retardants bound to car dust under Mediterranean climate

Polybrominated diphenyl ethers(PBDEs) are commercial flame retardants that have been commonly used in vehicle interior to reduce fire-related hazards. Due to high temperatures and intense insolation that can be attained inside cars parked in the sun, additive PBDEs are prone to leach out and attach to in-vehicle dust, as well as to photo-debrominate. This study examines seasonal variations of concentrations of three common PBDE congeners(BDE-47, BDE-99 and BDE-209) in car dust in Israel. The overall concentrations of these BDEs ranged from 1 to 29 μg/g, and were higher in the summer than in the winter(average of 10.2 and5.3 μg/g, respectively). Congener-specific concentrations showed distinct seasonal pattern,representing the interplay between leaching, evaporation and photodebromination. Photolysis of the three congeners, while adsorbed on glass filters and exposed to solar radiation, revealed first order kinetics with debromination rates on the order of 10-2/min. Hence, seasonal variations of the meteorological conditions were found to affect the in-vehicle PBDE concentrations, and are therefore expected also to affect the exposure of passengers to PBDEs.     

Daily, weekly, and seasonal time courses of VOC concentrations in a semi-urban area near Barcelona

In order to study the daily, weekly, and seasonal patterns and possible origins of air concentrations of volatile organic compounds (VOCs), measurements were taken on a minute-by-minute basis with a PTR-MS in the vicinity of a highway in a semi-urban site near Barcelona. Four periods of the year were chosen and samples were taken under different meteorological conditions and at different phenological stages of the surrounding vegetation. None of the measured VOCs concentrations exceeded air-quality guidelines. The results showed that diurnal, weekly, and seasonal fluctuations in measured VOC concentrations depended on variations in the strength of sources, as well as on photochemical activity and meteorological conditions. There was a decrease in concentrations in most VOCs when mixing depth, photochemical destruction, and wind speed increased at midday. On the other hand, high values of some VOCs occurred at night when the strength of their sinks and the mixing layer decreased. Interestingly, in June, night emissions and concentration peaks of methanol and acetone occurred in periods with dew formation and no wind. VOCs related to anthropogenic emissions presented a weekly pattern of variation with a clear distinction being found between working days and the weekend. The seasonal variation showed higher levels in December for all VOCs, except for isoprene. The thinning of the mixing layer leading to greater concentrations of volatiles and lower wind speeds in winter could account for those higher VOC levels. Benzene and toluene originated mainly from anthropogenic emissions. The sources of acetaldehyde, methanol, and acetone appeared to be mainly biogenic and these compounds were the most abundant of all the measured VOCs. Isoprene concentration patterns suggest a predominantly anthropogenic origin in December and March and a mainly biogenic origin in June and October. All these data provide useful information on the dynamics of VOCs in an area where ozone levels in summer exceed quite often the standard protection thresholds for O₃.     

A Rapid Decision-Making Method for the Evaluationof Pollution-Sensitive Coastal Areas in the Mediterranean Sea

Places of natural beauty and/or cultural value in the Mediterranean Sea are presenting adverse effects due to pollution. These environmental threats caused by point and nonpoint sources are mainly the reason why these areas represent “pollution-sensitive areas,” where the risk of deterioration is immediate. However, the risk will decrease and eventually disappear if protective measures are applied. In the present article, a multicriteria decision-making method is proposed for the prioritization of the Mediterranean sensitive coastal areas, taking into consideration criteria of pollution risk such as impact on human health, aquatic ecosystems, and socioeconomic value of the area. Weighting factors were then attributed to the different criteria according to their regional priorities, and a total pollution risk score was calculated for every sensitive area. However, some sensitive areas are more vulnerable than others because of their natural characteristics. Therefore, the total pollution risk score was then multiplied by a vulnerability weighting factor and a Total Sensitivity Score was calculated for every sensitive area. With this method, Mediterranean sensitive areas in coastal zones can be ranked on a priority list and then categorized according to their “sensitivity,” in a way that decision-makers can select the most urgent cases to direct their attention for the effective protection of the Mediterranean marine environment. The method is rapid and practicable and has already been used with existing data and information in several Mediterranean countries.     

APPLICATION OF THE RHESSys MODEL TO A CALIFORNIA SEMIARID SHRUBLAND WATERSHED1

ABSTRACT: Distributed hydrologic models which link seasonal streamflow and soil moisture patterns with spatial patterns of vegetation are important tools for understanding the sensitivity of Mediterranean type ecosystems to future climate and land use change. RHESSys (Regional Hydro‐Ecologic Simulation System) is a coupled spatially distributed hydroecological model that is designed to be able to represent these feedbacks between hydrologic and vegetation carbon and nutrient cycling processes. However, RHESSys has not previously been applied to semiarid shrubland watersheds. In this study, the hydrologic submodel of RHESSys is evaluated by comparing model predictions of monthly and annual streamflow to stream gage data and by comparing RHESSys behavior to that of another hydrologic model of similar complexity, MIKESHE, for a 34 km² watershed near Santa Barbara, California. In model intercomparison, the differences in predictions of temporal patterns in streamflow, sensitivity of model predictions to calibration parameters and landscape representation, and differences in model estimates of soil moisture patterns are explored. Results from this study show that both models adequately predict seasonal patterns of streamflow response relative to observed data, but differ significantly in terms of estimates of soil moisture patterns and sensitivity of those patterns to the scale of landscape tessellation used to derive spatially distributed elements. This sensitivity has implications for implementing RHESSys as a tool to investigate interactions between hydrology and ecosystem processes.     

粤东中生代火山旋回划分及对比

本文在基本查明火山岩系地层层序及变化的基础上,将粤东地区中生代火山岩划分为上、下两个岩系,四个旋回,对各旋回特征作了简要总结,并进行了区域对比分析。     

浙东中、新生代玄武岩起源、演化与地幔交代作用

浙东中,新生代玄武岩在诸多方面存在相当明显的差异,由此追溯其源区特征与演化过程中地幔交代作用的影响,对于了解浙东、乃至整个中国东南大陆火山带深部背景和火山带由中生代向新生代的转变机制有着重要意义。     

Fluoride distribution and the effect of some ions along Alexandria coastal Mediterranean seawater of Egypt

The coastal seawater of Mediterranean of Alexandria receives large amount of discharged waters containing industrial wastes, sewage, and agricultural and domestic drainage. Fluoride and some parameters were( chemical and physical) determined. The data gave indication that the content and the amount of the discharged water largely affect the chemical composition of the coastal water. Stepwise regression analysis was highly significant and the model was very fruitful, where the observed and calculated values were mostly concordant. This may indicated that there was a relation between fluoride content in cosslal seawater and its content in the discharged water.     

Modern sea level changes of the Eastern China Seas and their influences on coastal areas

The statistics of tidal gauging records showed that the mean sea level of the China Seas has risen for 14 cm in past 100 years. The annual mean sea levels of the Eastern China Seas have been rising at a speed of about 0.21 -0.23 cm/a since 1960. The annual mean sea levels of the Eastern China Seas in 1989 were 1.45 cm higher than that in 1988 on average.The sea level rise may cause the damage of the dynamical balance of the natural environments in the coastal area? and form or strengthen many coastal disasters, such as storm-tide catastrophic events, sea water invasion landward, soil salinization in coastal lowland and plains, and beach erosion retreat.