城市内河环境综合整治工程环境影响评价探讨

以南宁市竹排冲环境综合整治工程为例，探讨此类建设项目中施工扬尘、噪声、固废物处置及水土流失、底泥疏浚与处置的环境影响评价要点；针对项目施工期的环境影响和营运期对河流生态系统的影响，提出切实可行的环保措施和建议。     

Nutrient dynamics in shallow lakes of northern greece

GOAL, SCOPE, BACKGROUND: Shallow lakes display a number of features that set them apart from the more frequently studied deeper systems. The majority of lakes in Northern Greece are small to moderate in size with a relatively low depth and are considered as sites of high value of the wetland habitat. However, the water quality of these lakes has only been evaluated segmentally and occasionally. OBJECTIVE: The objectives of this study were to thoroughly investigate nitrogen and phosphorus speciation in lakes of a high ecological significance located in N. Greece, in order to evaluate their eutrophication status and possible nutrient limitation factors, and to investigate the main factors/sources that affect the water quality of these systems. METHODS: An extensive survey was carried out during the period from 1998-1999. Water samples were collected on a monthly basis from lakes Koronia, Volvi, Doirani, Mikri Prespa and Megali Prespa located in N. Greece. Water quality parameters (temperature, dissolved oxygen, pH and conductivity), organic indices (COD, BOD5), and N- and P-species (NO3(-), NO2(-), NH4(+), and PO4(3-), Kieldahl nitrogen and acid-hydrolysable phosphorus) were determined according to standard methods for surface water. Statistical treatment of the data was employed. RESULTS AND CONCLUSIONS: The physicochemical parameters determined in the lakes studied revealed a high temporal variation. The trophic state of the lakes ranged from meso- to hypertrophic. The nutrient limiting factor varied among lakes suggesting either P-limitation conditions or mixed conditions changing from P- to N-limitation throughout the year. Urban/industrial activities and agricultural runoff are the major factors affecting all lakes, although with a varying contribution. RECOMMENDATION AND OUTLOOK: This lake-specific research offers valuable information about water quality and nutrient dynamics in lakes of significant ecological value located in N. Greece that can be useful for an effective pollution control/management of these systems. Due to the large intra-annual variability of certain physicochemical parameters, a properly designed monitoring program of lake water is recommended.     

博罗县下村农场土壤养分概况

本文探讨了博罗县下村农场土壤养分含量概况，为今后长期试验研究提供基本理论依据。分析结果表明：下村场土镶有机质含量低，土壤酸性强，不利于土壤肥力的发挥，土壤全量养分Ｎ、Ｐ、Ｋ含量不平衡，速效养分虽然有些较高以至很丰富，但其含量范围大，有相当部分土壤仍很低，所以其供应水平亦很不平衡。而坡地赤红壤则全氮低，全磷不高，全钾则高低差异很大．至于果园土壤（即耕地），养分含量亦很不一致，相差极为悬殊，没有一定的规律性．土壤养分的高低水平，对作物的养分供应起很大的作用。由于下村场土壤养分的不均衡性，在生产管理上，应因地制宜，协调养分含量，以提高施肥效果。根据下村场土壤养分含量的特点，应增施有机肥，改良土壤，并适施石灰以改善土壤酸性，以利于作物的正常生长．     

天津近岸海域赤潮监控区富营养化状况评价

根据天津近岸赤潮监控区2003年度到2005年度的海洋环境监测资料,利用目前较为通用的富营养化综合指数法对该海域进行了富营养化评价,结果表明:(1)该区域富营养化现状整体呈现逐步恶化的现状,由2003年度的仅有一个站位发生轻微富营养化迅速恶化到2004年度、2005年度的严重富营养化;海水水质已经由2003年度的二类海水,锐减到2005年度的四类海水水质.(2)该区域严重富营养化现状主要是由陆源高营养盐(DIN和DIP)输入造成的.     

典型氟工业园周边河流沉积物中全(多)氟化合物的分布特征

采用超高效液相色谱/质谱联用(UPLC/MS-MS)分析了我国重要的氟化物工业园区周边河流——辽宁细河(阜新段)、山东小清河(淄博段)和长江(江苏常熟段)表层沉积物中全(多)氟烷基化合物(PFASs)的污染状况.细河表层沉积物中,PFASs含量范围(以干重计,下同)为15.8～2 770 ng·g~(-1),全氟丁烷磺酸(PFBS)和六氟环氧丙烷二聚酸(HFPO-DA)是主要污染物;小清河表层沉积物中,PFASs含量为12.2～7 853 ng·g~(-1),全氟烷基辛酸(PFOA)和HFPO-DA为主要污染物;长江表层沉积物中,PFASs含量为9.20～35.9 ng·g~(-1),全氟十四酸(PFTeDA)和6∶2氟调磺酸(6∶2FTS)为主要污染物.工业园区废水排放(点源污染)是本研究中3个区域PFASs的主要来源. 3个区域PFASs含量及组成差异明显,与工业园区生产规模和产业类型有关.PFASs含量及各组分含量与TOC、沉积物粒径没有显著相关性,PFASs各组分间相关性也有差异,说明PFASs在沉积物中的富集过程与多种因素有关.     

冬季太湖草、藻型湖区N2O的生成与排放特征

对太湖典型草（包括沉水植物及挺水植物湖区）、藻型湖区水-气界面N₂O排放通量、水柱溶存浓度、泥-水界面通量以及3个湖区的水柱及沉积物理化性质进行了原位观测及实验室分析研究,并针对影响N₂O生成与排放的主要环境因子进行了室内的微环境模拟试验.研究结果表明：水-气界面N₂O释放通量及泥-水界面N₂O释放通量为藻型湖区 > 沉水植物湖区 > 挺水植物湖区（（123.10±11.43）μg/（m²·h）,（79.19±4.90）μg/（m²·h）,（53.45±4.22）μg/（m²·h）和（29.60±0.20）μmol/（m²·h）,（10.89±1.66）μmol/（m²·h）,（3.83±0.30）μmol/（m²·h））;水体溶存N₂O浓度均为藻型湖区 > 挺水植物湖区 > 沉水植物湖区（（0.0247±0.0003）μmol/L,（0.0236±0.0003）μmol/L,（0.0219±0.0001）μmol/L）;室内微环境实验结果表明：冬季升高温度能够显著地提高N₂O的生成潜力,高盐度对3种生态类型湖区沉积物N₂O的生成速率总体表现出抑制作用,藻型湖区及挺水植物湖区沉积物N₂O释放潜力在添加Cl^-组明显高于控制组,氮盐度过高会抑制沉积物N₂O产生,而沉水植物湖区沉积物N₂O产生受到抑制;随添加NH+4-N和NO-3-N等营养盐浓度升高,藻型湖区及沉水植物湖区沉积物中N₂O生成速率增加,挺水植物湖区N₂O生成速率降低,而乙酸盐作为微生物活动的碳源和能源对N₂O生成表现出抑制作用.冬季太湖典型草、藻型湖区N₂O排放存在显著差异,冬季草/藻型湖区N2O生成主要受冬季低温的限制,另外也受水柱无机氮形态及浓度的影响.     

A RATING-CURVE METHOD FOR HYDRODYNAMIC SIMULATIONS IN CONTAMINANT TRANSPORT MODELING1

ABSTRACT: Accurate prediction of hydrodynamics is of great importance to modeling contaminant transport and water quality in a river. Flow conditions are needed in estimating potential exposure contamination levels and the recovery time for a no-action alternative in contaminated sediments remediation. Considering highly meandering characteristics of the Buffalo River, New York, a three-dimensional hydrodynamic model was selected to route upstream flows through the 8-km river section with limited existing information based on the model's fully predictive capability and process-oriented feature. The model was employed to simulate changes in water depth and flow velocity with space and time in response to variation in flow rate and/or water surface elevation at boundaries for given bottom morphometry and initial conditions. Flow conditions of the river reach where historical flow data are not available were computed. A rating-curve approach was developed to meet continuous and event contaminant modeling needs. Rating curves (depth-discharge and velocity-discharge relationships) were constructed at selected stations from the 3-D hydrodynamic simulations of individual flow events. The curves were obtained as steady solutions to an unsteady problem. The rating-curve approach serves to link flow information provided by the hydrodynamic model to a contaminant transport model. With the approach, the linking problem resulting from incompatible model dimensions and grid sizes can be solved. The curves will be used to simulate sediment movement and to predict contaminant fate and transport in the river.     

第四纪红壤不同熟化措施下的阴离子态养分含量及其剖面分布

本文对第四纪红壤及其发育的土壤中的６种必需阴离子态养分含量及其在土壤剖面中的分布进行了系统的讨论．结果表明，第四纪红壤中的各种必需阴离子态养分含量与土壤耕作熟化措施有关．荒地的ＮＯ、Ｃｌ－、Ｈ２ＢＯ较高，而开垦为旱地后，它们的含量下降；Ｈ２ＰＯ在土壤经过耕作熟化后有所提高；ＭｏＯ的含量则基本保持不变；与其它阴离子显著不同的是．经耕作熟化后，土壤有效性ＳＯ含量急剧增加，不同的阴离子态养分在土壤剖面中的分布特点不同．     

鄂尔多斯不同地形下土壤养分的空间变异

通过野外调查采样与室内土壤理化分析相结合,对鄂尔多斯荒漠区不同地貌类型下的土壤养分分布特征进行了初步分析,研究表明:鄂尔多斯沙地土壤养分含量普遍较低,两断面表层有效钾的均值在６４．７３－７０．９５ｍｇ/ｋｇ之间,有机质含量在０．４９３%－０．５０８%之间,ｐＨ值在８．０左右。在地形部位较高的硬梁、丘顶处土壤养分含量最低,软梁次之,而在地势较低的滩地、丘间地土壤养分含量较高。硬梁、软梁、滩地表层土壤有机质和有效钾含量分别为０．１８%、０,５０%、１．１６%和 ３５．２９ｍｇ/ｋｇ、６０、６７ｍｇ/ｋｇ、９８．３２ ｍｇ/ｋｇ,丘顶、丘间、农田表层土壤有机质和有效钾的含量分别为０．０９%、１．０９%、０．８４%和２３．９１ ｍｇ/ｋｇ、６０．３４ｍｇ/ｋｇ、７７．４２ ｍｇ/ｋｇ。在多数土壤剖面上,土壤养分从上到下递减。通过对两地形断面上土壤有机质和有效钾的一维半方差函数均表现出明显的空间结构性,并且各种养分的独立较大,在艾碱壕断面上土壤有效钾和有机质的独立间距为７０．８９ｍ和６９．１５ｍ,在深海沟断面上土壤有效钾和有机质的独立间距为１２．４８ｍ和３５．９８ ｍ,说明在调查区域内土壤养分存在一定的相关关系。     

Cycling of metals in desert soils: effects of Tamarix nilotica and inundation by lake water

Concentrations of Ca, Mg, K, Na, Cu, Zn, Al, Fe and Mn were measured in soils and in Tamarix nilotica from Wadi Allaqi on the shore of Lake Nasser in the Eastern Desert of Egypt. All of the elements were concentrated in the leaves of Tamarix relative to the stems and roots. Leaf:soil concentration ratios, used as an indicator of metal accumulation in the plant, showed high enrichment factors for Na (67.5), K (63.0) and Mg (35.0); of the trace elements measured, Zn had the highest enrichment factor (7.64). Comparison with other desert species suggested that Tamarix was exceptional only in the accumulation of sodium. Periodic inundation of the soil by Lake Nasser caused dilution and dispersion of the accumulated salts.