Beryllium Chemistry in the Lysina Catchment,Czech Republic

The environmental chemistry of beryllium (Be) was investigated at the Lysina catchment in western Bohemia, Czech Republic, a forest ecosystem with high loadings of acidic atmospheric deposition. The catchment supports Norway spruce plantations; it is underlain by leucogranite and the soils are Spodosols. Average concentrations of Be were high in groundwater (3.3 µg L-1) and in stream water (1.5 µg L-1), in comparison to the drinking water standard of the Czech Republic (0.2 µg L-1). Chemical equilibrium calculations suggest that aquoberyllium Be2+ was the prevailing inorganic species in drainage waters at the site. Atmospheric deposition of Be (45 µg m-2 yr-1) was small in comparison to drainage outflow (586 µg m-2 yr-1) at Lysina. Elevated Be concentrations in drainage water appear to be the result of the mobilization of Be from soils and weathered bedrock due to acidic atmospheric deposition. Increased mobility of Be due to acidification may have serious ecological consequences in acid-sensitive areas with terrestrial pools of available Be.     

Retention Capacity and Environmental Mobility of Pb in Soils along Highway Corridor

Although lead (Pb) emissions have dropped drastically with the phase-out of tetra-ethyl lead (TEL) as a fuel additive, Pb deposited along highway corridors continues to be of concern because of its toxicity. This paper provides comprehensive data on the extent and distribution of Pb in roadside soils, Pb interaction with soils as a function of soil composition, the retention capacity of soil based on batch adsorption tests, the retention mechanism of Pb using selective sequential extraction, the potential for mobility using batch desorption tests with simulated rain and winter road salt, and column leach tests. Highway soils on high-traffic sections near Burnaby, Canada were found to have Pb accumulations up to 1628mg/kg soil. Contamination was mainly in the top 0.3m, with concentrations rapidly decreasing to the background level at a depth of 0.6m. The top layer contained more organic material and had a high adsorption capacity. Highway soils were found to have 3–10 times higher Pb adsorption capacities than the amount currently deposited. Selective sequential extraction indicated low exchangeable Pb in highway soils. Batch desorption tests with leaching solutions of H₂O (pH 5.5), HNO₃ solution (pH 4.0) and aqueous NaCl solution (0.17M) indicate low likelihood of significant leaching. Selective sequential extraction, leachate extraction and desorption tests show that Pb has limited mobility in highway soil.     

祁连山天老池小流域土壤有机碳空间异质性及其影响因素

采用野外取样和室内分析,结合地统计学方法和方差分析方法,分析了祁连山天老池小流域0~30 cm层的土壤有机碳的分布特征及其与植被类型、地形和土壤性质等因素的关系。结果表明,该流域土壤有机碳垂直分布存在显著的差异,随着土层深度的增加,土壤有机碳含量显著减少,0~10、10~20、20~30 cm土层土壤有机碳含量分别为105.08、81.46、62.62 g/kg,土壤平均有机碳含量为83.05 g/kg,变异系数为0.56。不同的植被类型0~10 cm土层土壤有机碳含量表现为青海云杉(138.20 g/kg)灌丛(118.49 g/kg)亚高山草甸(100.43 g/kg)祁连圆柏(74.17 g/kg)干草原(43.94 g/kg);随着海拔的升高土壤有机碳含量增加,阴坡有机碳含量明显高于阳坡;经相关性分析表明,土壤有机碳与土壤全氮和砂粒呈显著正相关关系,与土壤体积质量、黏粒和粉粒呈显著负相关关系。     

黄土高原昕水河流域径流变化及其对环境要素的响应

以黄土高原昕水河流域为对象,采用有序聚类等数理统计方法,诊断了近60 a来实测径流的变化及其阶段性特征,在此基础上,分析了不同阶段实测径流与气候要素之间的响应关系,初步揭示了径流演变的驱动机制。结果表明:近60 a来昕水河流域实测径流量以1965年和1979年为分割点总体呈现阶段性减少趋势,其中,21世纪以来减少尤其明显。不同阶段的年降水、径流关系有一定差异,相比而言,汛期（6—10月份）的月降水量与径流量具有相对较好的相关关系,非汛期（11—5月份）的月降水径流关系点群散乱。积雪及融雪对河川径流量的影响存在±5℃阈值,当气温介于该阈值区间,气温变化对河川径流影响较大。昕水河流域汛期产流受高强度降水支配,非汛期径流量以地下径流和融雪径流为主。人类活动对河川径流的影响有增大趋势。     

Effect of Ionic Composition and Temperature on the Radiocaesium Fixation in Freshwater Sediments

The objective of this study was to verify in which way the ionic composition of the sediment and that of the overlying water column may have an effect on radiocaesium fixation, through possible structural modifications of the frayed edge sites (FES) pools of the sediments. Two experimental protocols have been considered: i) a condition in which sediments were homoionically saturated with either potassium, ammonium, calcium, magnesium or sodium ions. and ii) a mixed potassium-calcium scenario in the liquid phase. Nine freshwater sediments from four different locations were used in this study. For homoionic potassium and ammonium saturated sediments a nearly quantitative radiocaesium desorption (90–100%) was observed, whereas for calcium and magnesium the desorption yields scene about 20%. It appears that the action of strongly hydrated ions (Na⁺, Mg²⁺, Ca²⁺) leads to a pronounced enhancement of radiocaesium fixation in the solid phase, whereas poorly hydrated ions (K⁺, NH₄ ⁺) have the opposite effect and promote sorption reversibility. Another issue considered in this study concerns the effect of temperature and sediment drying on the radiocaesium fixation. Drying die sediments at 110°C leads to a significant increase in radiocaesium fixation levels, while drying the sediments at room temperature (25°C) has a very limited effect on radiocaesium fixation and appears to put a brake on the aging effects.     

陕北黄土丘陵区燕沟小流域综合治理的经济响应

以陕北黄土丘陵区燕沟小流域为对象,采用农村社会调查和统计资料相结合的方法,分析小流域水土保持和退耕还林(草)工程建设以来流域经济特征的变化,阐明小流域综合治理对农村发展的主要影响.结果湿示,流域农村各业产值和农民人均纯收入(1990年不变价)分别由2000年的803万元和1 230元提高到2005年的1 069万元和1 855元,表征产业结构多样性的香农指数也相应的由1.110增加到1.126.恩格尔系数、基尼系数和贫困指数等计算结果表明流域农民生活状况和收入分配明显得到改善.研究表明通过积极的土地利用和农村产业调整,基本上建立了适合于流域土地利用结构和自然特点的特色产业链条,产业结构也由原来单一的种植业向多元化产业结构演变,小流域综合治理使流域社会经济发展水平得到了整体提升.     

西苕溪流域非点源氮污染特征

通过对西苕溪流域不同用地类型的子流域出口设置监测点并进行定期水质监测,探讨该流域非点源氮污染特征及其区域性差异。不同月份的监测结果表明,总氮（TN）、溶解性总氮（DTN）、硝态氮（NO3--N）浓度在12月最高,7月次之,4月最低;铵态氮（NH4＋-N）浓度在7月最高,12月次之,4月最低。典型子流域日监测数据表明：林地子流域水质监测点测得的氮明显低于耕地,降雨期林地子流域出口的氮浓度增加,耕地子流域降低,干旱期则相反。研究表明流域非点源氮污染主要受农业耕地用地类型的控制,降雨径流是西苕溪流域非点源氮输出的主要驱动因素,用地类型、不同形态氮的理化性质差异导致流域非点源氮呈现明显的季节、空间分布特征。     

Polychlorinated biphenyls in soils of Belarus: Sources,contamination levels,and problems of study

Polychlorinated biphenyls (PCBs) in soils of Belarus were studied. The PCB concentrations in reference soils were determined. High accumulation levels of PCBs were found at the working and storage sites of PCB-containing electrical equipment. Soil contamination under PCB leakage from damaged capacitors and transformers was analyzed. Contamination of the Lakokraska plant site and adjacent areas (Grodno oblast) because of the long-term use of the Sovol was revealed. The structure of the PCB isomers in the soils was described depending on the contamination source.     

Lead in the Soils and Stream Sediments of an Urban Catchment in Tyneside,UK

This paper focuses on lead contamination in topsoils and stream sediments of public access areas in a largely urban UK catchment. It compares severity of contamination with accepted trigger thresholds, examines spatial patterns relative to urban and industrial development, and explores potential mobility of lead using ‘plant available’: total lead ratios. Total and ‘plant available’ lead concentrations, organic content and pH were determined on 298 topsoil and 54 stream sediment samples using standard laboratory procedures. At the lowest total lead trigger threshold, approximately two thirds of topsoil and one third of stream sediment samples were contaminated. For ‘plant available’ lead the proportions were somewhat lower. The spatial pattern was characterised by ‘hot spot’ contamination, with highest values occurring in central and southern parts of the catchment which have a long urban and industrial history. Potential lead mobility is greatest in rural western and northern parts of the catchment where the lead fractions are probably derived from pedological alteration and weathering of soil parent materials. Conversely, in the urban and industrial areas, much of the lead probably consists of less mobile particulate forms. The implications of these findings for assessment, monitoring and management of contaminated areas are discussed.     

The Nature and Distribution of Metals in Soils of the Sydney Estuary Catchment, Australia

Total topsoil 50th percentile Cu, Pb and Zn concentrations (n?=?491) in the Sydney estuary catchment were 23 ??g?g^?1, 60 ??g?g^?1 and 108 ??g?g^?1, respectively. Nine percent, 6% and 25% of samples were above soil quality guidelines, respectively and mean enrichment was 14, 35 and 29 times above background, respectively. Soils in the south-eastern region of the catchment exhibited highest metal concentrations. The close relationship between soil metal and road network distributions and outcomes of vehicular emissions modelling, strongly suggested vehicular traffic was the primary source of metals to catchment soils. Catchment soil and road dust probably make an important contribution to contamination of the adjacent estuary. The concentration of soil metals followed the land use trend: industrial?>?urban?>?undeveloped areas. A high proportion (mean 45%, 62% and 42%, for Cu, Pb and Zn, respectively) of metals in the soils may be bioavailable.     

云南省洱海流域农业生态补偿机制研究

围绕洱海流域种植业产业结构调整、畜禽废弃物资源化利用问题,依托项目示范对农业生态补偿机制进行研究。以大理州政府为补偿主体,示范区内农户为补偿对象,结合资金补贴、技物补偿、智力扶持等补偿途径,开展测土配方施肥、发酵床生态养猪、稻田养鱼、牛粪秸秆混种双孢菇等典型农业生态补偿模式研究,提出了1套农业生态补偿办法。针对补贴力度...     

虱螨脲在土壤中的降解、吸附和移动特性

采用室内模拟试验方法,研究了虱螨脲在3种土壤中的降解、吸附和移动特性。结果表明：25℃下,虱螨脲在江西红壤中的降解半衰期为101d,属于中等降解农药;在太湖水稻土和东北黑土中的降解半衰期分别为74.5d和55.5d,属于较易降解农药。土壤有机质含量是影响虱螨脲降解速率的主要因素;3种土壤对虱螨脲具有较强的吸附性,且土壤有机质含量越高,对虱螨脲的吸附性越强;3种土壤对虱螨脲的吸附自由能变化均小于40kJ·mol^-1,属于物理吸附;虱螨脲在土壤中不易移动,正常条件下不会造成地下水的污染。     

霍林河流域湿地土地利用/土地覆被类型的渐变过程

研究了霍林河流域自然湿地和人工湿地的面积动态变化以及土地利用/覆被变化过程——渐变过程,结果表明1986～2000年期间自然湿地的面积呈缩减变化,而人工湿地面积则呈增长变化;1986～1996年期间除河流湿地没有发生渐变过程外,其它类型湿地之间普遍存在着渐变过程,其中沼泽的渐变过程最为显著,表现为大幅度缩减,而滩地、湖泊、水库坑塘和水田在渐变过程中则表现为增加变化。1996～2000年期间各类型湿地之间普遍存在着渐变过程,但不同的是,沼泽湿地面积在渐变过程中表现为大幅度增加,而河流、滩地、湖泊和水库坑塘却表现为大幅度缩减;同时沼泽、滩地、湖泊以及水库坑塘在此期间都有向水田发生转变,表明人类的活动范围在不断的扩展,对湿地的开垦力度也在不断加强。     

霍林河流域湿地土地利用／土地覆被类型的转换过程

研究了霍林河流域自然湿地和人工湿地土地利用/土地覆被类型的转换过程,结果表明1986～1996年期间自然湿地主要与未利用地、草地、林地和耕地发生转换,其中沼泽主要与草地发生转换;滩地、湖泊和河流主要与未利用地、草地和林地发生转换,并有少量滩地和湖泊被开垦为耕地;人工湿地主要与未利用地发生转换。1996～2000年期间自然湿地中除沼泽转换关系主要发生在沼泽与耕地之间外,河流、滩地和湖泊主要与未利用地发生转换关系;与上一阶段一致,人工湿地主要与未利用地发生转换关系。研究也进一步表明,前一时期自然湿地受自然因素的影响强于人为干扰,而在后一时期内人为干扰作用开始加强。     

GIS支持下小流域农林复合经营的侵蚀控制模拟——以冀西北青边口河小流域为例

根据张家口郭家梁试验场的小区资料 ,建立了小流域侵蚀产沙模型以及植物篱侵蚀控制模型 ;并在 GIS的支持下 ,从小流域数字高程模型 (DEM)中提取基于地块间水沙汇流网络 ,生成基于地块的水沙运移网络图 ,并将地块间的水沙汇流过程引入小流域侵蚀产沙的模拟中 ,实现了侵蚀产沙模型与地理信息系统 (GIS)的深层次耦合 ,模拟出坡面水沙在小流域的空间运动过程。1995～ 1999年青边口河小流域模拟结果表明 ,坡耕地、荒坡地、低覆盖的天然草地平均侵蚀模数最大 ,是侵蚀控制的重点土地利用类型。在坡耕地、荒坡地、低覆盖的天然草地配置面积占流域总面积的 18.2 %的植物篱—农作系统 (10 m带间距 2年生紫穗槐植物篱 ) ,利用次降雨资料计算模拟结果表明 ,对径流的控制效果在 8.1%～ 46 .2 %之间 ,对侵蚀模数的控制效果在 42 .9%～ 5 0 .2 %之间 ;养分流失的模拟分析表明 ,在现有条件下有机质的损失较大 ,而通过配置植物篱—农作系统可以有效地减少养分流失。     

A series of 19'-hexanoyloxyfucoxanthin derivatives from the sea mussel, Mytilus galloprovincialis, grown in the Black Sea, Ukraine

A series of carotenoids with 19- or 19'-hexanoyloxy moieties, 19'-hexanoyloxyfucoxanthin (1), 19'-hexanoyloxyfucoxanthinol (2), 19'-hexanoyloxyhalocynthiaxanthin (3), 19-hexanoyloxycrassostreaxanthin A (4), 19-hexanoyloxymytiloxanthin (5), and 19-hexanoyloxyallenicmytiloxanthin (6) were isolated from the edible part of the sea mussel, Mytilus galloprovincialis, grown in the Black Sea, Ukraine. Among them, 3, 4, and 6 were new compounds. These structures were charcterized by UV-vis, fast atom bombardment mass spectrometry, circular dichroism, and (1)H NMR spectroscopic data. They were assumed to be metabolites of 19'-hexanoyloxyfucoxanthin (1).     

Regional Patterns of Streamwater Acidity and Catchment Afforestation in Galloway,SW Scotland

This paper investigates the regional relationships between highflow water chemistry and conifer forest cover in 95 streamsspread over an area of approximately 2000 km² in Galloway,south-west Scotland, paying particular attention to the use ofdetailed catchment area data. Catchment forest data areextracted from a 30 m resolution tree height map derived fromsatellite imagery; geology data from a digital geology map; andaltitude and slope data from a 50 m resolution Digital TerrainModel (DTM). The results show that over the entire region pHlevels are lower with increasing catchment afforestation whilstaluminium concentrations are higher. Concentrations of sulphate arealso higher with increasing afforestation, which suggests thatconifers play a primary role in increasing the acidity levels ofstreams by exacerbating aerial acid deposition in the entireregion.     

Clay mineralogy in agrochernozems of western Ukraine

The mineralogy of clay fractions separated from deep low-humus deep-gleyic loamy typical agrochernozems on loess-like loams of the Upper Bug and Dniester uplands in the Central Russian loess province of Ukraine consists of complex disordered interstratifications with the segregation of mica- and smectite-type layers (hereafter, smectite phase), tri- and dioctahedral hydromicas, kaolinite, and chlorite. The distribution of the clay fraction is uniform. The proportions of the layered silicates vary significantly within the profile: a decrease in the content of the smectite phase and a relative increase in the content of hydromicas up the soil profile are recorded. In the upper horizons, the contents of kaolinite and chlorite increase, and some amounts of fine quartz, potassium feldspars, and plagioclases are observed. This tendency is observed in agrochernozems developed on the both Upper Bug and Dniester uplands. The differences include the larger amounts of quartz, potassium feldspars, and plagioclases in the clay material of the Upper Bug Upland, while the contents of the smectite phase in the soil profiles of the areas considered are similar. An analogous mineral association is noted in podzolized agrochernozems on loess-like deposits in the Cis-Carpathian region of the Southern Russian loess province developed on the Prut–Dniester and Syan–Dniester uplands. The distribution of particle-size fractions and the mineralogy of the clay fraction indicate the lithogenic heterogeneity of the soil-forming substrate. When the drifts change, the mineral association of the soils developed within the loess-like deposits gives place to minerals dominated by individual smectite with some mica–smectite inter stratifications, hydromicas, and chlorite.