基于二维小波分析的景观特征尺度识别

采用3种常用小波基（Haar、Daubechies和Symlet）,探讨了二维小波分析在沈阳地区城市、城乡交错区和农村3种景观类型特征尺度识别中的有效性.由于二维小波分析的变换尺度必须为2的整数次幂,这会导致景观中一些特征尺度无法精确识别,故本文将各景观类型影像像元大小分别重采样为3、3.5、4和4.5 m,以增加分析时的尺度密度.结果表明：应用二维小波分析可清晰地识别景观特征尺度;Haar、Daubechies、Symle可分别作为城乡交错区景观、城市景观和农村景观特征尺度识别的最优小波基;Haar和Symlet均可应用于农村景观精细特征尺度的识别和城乡交错区景观边界的检测;Daubechies和Symlet可分别用于城市景观和农村景观的边界检测.     

Heavy metals contamination in shallow groundwater of a coal-mining district and a probabilistic assessment of its human health risk

To manage public health and make better use of groundwater resources, the concentration characteristics and a health risk assessment of eight heavy metals in shallow groundwater were studied. Besides this, this paper introduced triangular fuzzy numbers into the USEPA health risk assessment model to assess the health risk posed to local children and adults through different exposure pathways. The results showed that Mn levels exceeded the WHO’s guideline values of 100?µg/L with the proportion of 27.98% and Sr were over the health reference level (HRL) of 1500?µg/L with the proportion of 56.25%, while other heavy metals were below the corresponding standard. The results of the HRA showed that the non-carcinogenic risks from Sr and Mn in the district were relatively higher, while those from the remaining six heavy metals were relatively lower. All hazard index (HI) values did not exceed the safety level of 1 for either age group. The average carcinogenic risk from Cr was slightly higher than the acceptable level of 1?×?10^?6 for adults. Sensitivity analyses conducted using Monte Carlo simulation indicated that Sr and Cr concentrations were the most influential variables contributing to the non-carcinogenic and carcinogenic risk values, respectively, while body weight had a minor contribution.     

Odense Pilot River Basin: implementation of the EU Water Framework Directive in a shallow eutrophic estuary (Odense Fjord,Denmark) and its upstream catchment

Implementation of the EU Water Framework Directive (WFD) is a huge environmental management challenge for Europe, demanding an integrated sustainable approach to water management and a common objective of obtaining ‘good status’ for all water bodies before 2015. The main task is the preparation of a river basin management plan for each of the 96 European river basin districts before the end of 2009. In Odense River Basin (island of Fyn, Denmark), one of 14 appointed European Pilot River Basins, the implementation of the WFD has been developed and tested in practice. Reference conditions and ecological status classification for Odense Fjord, based on eelgrass (Zostera marina) depth limit and nutrient concentrations, have been drawn up through a combination of historical data and modelling tools. A subsequent quantitative linking of pressures and impact, in casu between land-based nitrogen (N) loading of the fjord and resulting nutrient concentrations and eelgrass appearance, provided an estimate of the needed nitrogen load reduction of the fjord. This amounted to approx. 1,200 tonnes N per year (an annual load reduction of ca. 11 kg N ha^?1 of catchment area or ca. 19.5 g N m^?2 of fjord surface)—a load reduction of ca. 60% from the present level—to obtain at least ‘good’ ecological status sensu WFD. It is presently not possible to quantify a target load for phosphorus (P) in relation to marine environmental objectives. An economically feasible programme of measures to obtain ‘good’ status in all surface water and groundwater bodies in Odense River Basin, using an integrated cost-effectiveness analysis, showed that re-establishment of wetlands, catchcrops, and reduced fertilisation norms are the most effective measures if large reductions in N loads to the aquatic environment are to be achieved. The total socio-economic cost of implementing the WFD in the river basin amounts to about 13 million €/year, which will increase the expense for water services by only 0.5–0.6% of the total income and production value in the basin (15,650 million €/year). Investments to obtain the needed nitrogen load reductions from agriculture are thus economically feasible. Further, it is not an impossible task, either economically or technically, to reach the objectives of the WFD while still retaining the possibility of keeping a high agricultural production in the catchment (maintaining livestock production but decreasing crop production in the case of Odense River Basin). The future conditions in Odense Fjord will not only depend on the success in reducing the load from the river basin area, but will also be affected by the trend in the nutrient loss from the whole Baltic catchment area. The high growth rates in the new EU Member States thus pose an important challenge to water managers, and decoupling of economic growth from pressure on water bodies will be necessary. Finally, a number of challenges facing water managers around the Baltic and within the EU, namely preconditions required to successfully implement the WFD, are presented.     

Tyrrhenian basins of Ligury as a new peri-Mediterranean ichthyogeographic district? Population structure of <Emphasis Type="Italic">Telestes muticellus</Emphasis> (Osteichthyes,Cyprinidae), a primary freshwater fish

The phylogeographic structure of vairone (Telestes muticellus), a primary freshwater fish endangered in a large part of its distributional range, was assessed: (i) to reconstruct the complex dispersion pattern in the upper Tyrrhenian hydrographic basins of Ligury, actually not recognised as peri-Mediterranean ichthyogeographic district, and (ii) to evidence the shape of population genetic structure as useful tool for future conservation strategies. A partial fragment of mitochondrial DNA cytochrome b (497 bp) was sequenced in 109 specimens sampled from eight populations, along an east–west geographic gradient. Fourteen haplotypes were identified, confirming the evolutionary distance between the two co-generic species: T. muticellus as ‘Ligurian’ clade and T. souffia as ‘French’ clade. The Nested Clade Analysis (NCA), the population genetic variability and population structure suggested a natural colonization occurred throughout the crossing of Alpine and Apennine watershed. The hierarchical Analysis of Molecular Variance (AMOVA) confirmed a geographic distinction between the populations from western (WTL) and from eastern (ETL) Tyrrhenian basins of Ligury colonised through the river capture processes along the Maritime Alpine watershed (Padano-Venetian district) and along the Apennine watershed (Tuscano-Latium district), respectively. Our results, evidencing the lack of genetic contiguity among vairone populations of the upper Tyrrhenian hydrographic basins of Ligury, allowed to recognise the presence of two management units (MUs) for its conservation. Handling editor: Christian Sturmbauer     

A Contribution to the Determination of Polychlorobenzenes in Sediments

A full analytical procedure involving extraction and clean-up is presented for the determination of the tri-, tetra-, penta- and hexa-chlorobenzenes in sediments. For this study, the gas chromatography coupled to electronic capture detection was used.

The samples were dried with sodium sulphate and Soxhlet extracted for 16 hours with dichloromethane. Then this solvent was replaced by hexane and the resulting solution was concentrated in a rotary evaporator. The clean-up process consisted of elution through a mixed silica column followed by a treatment with activated copper turnings to remove the sulphur. The sample was then concentrated down to 2 mL by nitrogen stream. The internal standard, 1,4-dibromobenzene, was added to the sample prior to the extraction, whereas the injection standard, 1,3,5-tribromobenzene, was added right before the sample was injected through the chromatographic system.

The limits of quantification ranged from 71 to 500 pg g^?1 (dry weight). The reproducibility in the peak areas within a day was better for the compounds with increasing number of chlorines, whereas the reproducibility over time studies provided no significant differences in the peak areas in consecutive days.

The method was successfully applied to the determination of polychlorobenzenes in a certified sediment and, finally, it was applied to the determination of these compounds in several sections of a sediment core from Esthwaite Water Lake (United Kingdom).     

天河区土地利用状况及可持续利用对策

分析了广州市天河区近年来的土地利用情况 ,总结出天河区土地利用的特点 ,指出在土地利用过程中存在着人均用地减少 ,非农建设用地迅速扩展 ,用地结构不合理 ,土地污染等问题 ,最后从维护生态环境和土地的可持续利用出发 ,对天河区的土地利用保护提出了几点对策性建议。     

基于样带—地理探测器的陆桥通道沿线建制市建成区绿地率区域差异影响机理研究

在中国新型城镇化转型发展背景下，科学认识城市绿地建设水平的影响机理是提升人居环境质量、实现城市绿色发展的重要前提。选取陆桥通道样带为研究区域，采用地理探测器方法，探究 1996—2016 年沿线样带 139 个建制市建成区绿地率区域差异的影响机理。研究表明： 1）沿线样带市域建成区绿地率逐年提升，但存在明显时空分异，呈东西部两头高、中部低的“U”型格局； 2）地理探测显示样带市域建成区绿地率差异是自然、经济和政策等因素非线性或双因子作用的结果，年均温为核心主导因子，园林城市政策、海拔高程是次要解释力； 3）自然地理本底是奠定差异的重要基础，政策引领是关键，经济水平是直接推动因素，产业结构、土地供给和基础设施为外部主导动力。研究定量化呈现了自然因素对城市绿地建设水平区域差异的大尺度、长期性影响；探测“自然—经济—政策”多维因素的综合作用，更精准地对城市绿地建设分类施治，是典型区域和典型方法在学科领域的一次尝试。     

The distribution of Raunkiaer life forms in Israel in relation to the environment

Abstract. The distribution of Raunkiaer life forms along rainfall and temperature gradients was determined for the floras of 27 geomorphological districts in Israel. Phane-rophytes and chamaephytes are relatively strongly represented in districts with very low rainfall, decrease up to 150 mm and 400 mm of mean annual rainfall respectively, and remain more or less constant at higher rainfall figures. Hemicryptophytes andgeophytes increase along the rainfall gradient. Therophytes show an optimum between 200 and 500 mm of rainfall. The distribution of life forms is less clearly correlated with mean annual temperature, though hemicryptophytes and geophytes show a negative correlation with mean annual temperature and with mean annual minimal temperature.