架桥后汤逊湖水体水质现状及其治理对策

为了鉴定武汉市汤逊湖桥梁建成后汤逊湖水体水质状况,2010年12月至2011年3月于汤逊湖沿线11个点多次采水样,以水体总氮、总磷、叶绿素a、COD及透明度等为参数,对水体理化因子、水质状态特征、富营养化程度等进行分析,探讨各影响因子对汤逊湖富营养化的影响程度.结果表明,汤逊湖目前处于轻度富营养化状态,工业废水、生活污水及水产养殖是汤逊湖的主要污染源.可通过加强对湖区工业污染源、城市生活污水、农业生产等污染的外源控制以及对湖区内的水产养殖污染的内源控制和科学管理,加强湖泊生态修复工程治理力度等方式进行调控.提出了汤逊湖水质富营养化治理的基本对策.     

洞庭湖区杨树食叶害虫蛹期天敌调查及优势天敌筛选

湖南洞庭湖区杨树食叶害虫蛹期天敌有啮小蜂(Tetrastichus spl.)、白蛾黑基啮小蜂(Tetrastichus nigricoxae)、日本追寄蝇(Exorista japonica)、毛虫追寄蝇(Exorista dmoena)、伞裙追寄蝇(Exorista civilis)、双齿多刺蚁(Polyrhach...     

修正Logistics模型在水污染经济损失计算中的应用

传统的Logistic模型在湖泊水污染经济损失计算上存在较大的偏差。通过对Logistic模型参数A、B值的修正,提高了TN、TP在模型计算中的所占比重。将修正前后的模型运用于邛海的水污染经济损失估算中,并将结果与邛海多年的水质综合污染指数的变化趋势进行比较。计算结果表明,修正后的Logistic模型计算的邛海水污染经济损失更符合邛海水污染多年的变化情况。修正后的Logistic模型可推广应用于其他湖泊的水污染经济损失计算中。     

杭州西湖风景区夏季观花植物种类及应用分析

对杭州西湖风景区夏季观花植物的种类和应用现状进行实地调查,分析了西湖风景区夏季观花植物景观应用形式,并针对存在的问题提出建设性意见,可为园林建设中的夏季植物造景提供参考。     

洞庭湖区移民工程与安置地可持续发展初探 —以湖南省安乡、汉寿和岳阳县为例

探讨了洞庭湖区地方经济发展与移民安置容量之间关系、移民工程与安置地区可持续发展之间相互作用 ,并提出移民安置工程对策建议     

~(137)Cs示踪法估算滇池流域土壤侵蚀

用13 7Cs示踪法探讨滇池流域的土壤侵蚀表明 ,不同利用方式农田的侵蚀量从 2 2 4t km2 yr(菜地 )～ 345 6t km2 yr(园地 )。与太湖地区相比 ,粗放的耕作方式也改变了当地农田的侵蚀排序。特别是土壤中的13 7Cs含量为 35 5～ 872Bq m2 ,比世界其他许多地区都低 ,却与青藏高原相邻地区的数值相近。原因可能是气候特点及远离核试验中心。经与其他方式所得结果比较可见 ,用13 7Cs示踪法研究滇池流域的中长期土壤侵蚀既简便快速又合理可行。     

黔西高原地区降雨侵蚀力的简易算法

[目的]对黔西高原地区侵蚀性降雨特性进行分析并探索降雨侵蚀力的简易算法,为该区土壤侵蚀预报模型的建立提供理论依据。[方法]利用径流小区观测法,基于毕节小区2012—2014年53次降雨过程资料进行分析。[结果](1)降雨量(P)和最大60min降雨动能(E60)是影响坡面产流、产沙的两个主要因子。坡面产流、产沙与最大60min雨强(I_(60))显著相关;(2)坡面产流产沙与二元复合因子的相关系数显示,EI_(60),PI_(60)和I30I_(60)是影响坡面产流、产沙的3类主要降雨复合指标,EI30和EI_(60)与坡面产流产沙的相关系数间相差较小;(3)基于坡面产流、产沙与降雨单指标和降雨复合指标的相关关系,确定了简易算法的参数。[结论]基于可比性,以R=EI30作为参照值对3种简易算法的结果进行决定系数和偏差率比较后,得到研究区便捷、快速的降雨侵蚀力简易算法为:R=0.344(PI_(60))。     

高岭石和氧化土悬液中铝的水解行为及有机酸对铝水解反应的影响

To evaluate the role of kaolinite and variable charge soils on the hydrolytic reaction of Al, the hydrolysis of Al ions in suspensions of a kaolinite and an Oxisol influenced by organic anions was investigated using changes of pH, Al adsorption, and desorption of pre-adsorbed Al. Kaolinite and the Oxisol promoted the hydrolytic reaction of Al above a certain initial Al concentration (0.1 mmol L^-1 for kaolinite and 0.3 mmol L^-1 for the Oxisol). The Al hydrolysis accelerated by kaolinite and the Oxisol increased with an increase in initial concentration of Al and was observed in the range of pH from 3.7 to 4.7 for kaolinite and 3.9 to 4.9 for the Oxisol. The acceleration of Al hydrolysis also increased with the increase of solution pH, reached a maximum value at pH 4.5, and then decreased sharply. Al hydrolysis was promoted mainly through selective adsorption for hydroxy-Al. Soil free iron oxides compensated a portion of the soil negative charge or masked some soil surface negative sites leading to a decrease in Al adsorption, which retarded acceleration to some extent. For the Oxisol organic anions increased the proportion of adsorbed Al³⁺ in total adsorbed Al with the increase in soil negative surface charge and eliminated or reduced the acceleration of Al hydrolysis. Different organic anions inhibited the hydrolysis of Al in the order: citrate > oxalate > acetate (under initial pH of 4.5). The formation of Al-organic complexes in solution also inhibited the hydrolysis of Al.     

Land use change and erosional history in a lake catchment system on the Canadian prairies

The introduction of agriculture in the late 1800s and early 1900s brought about many changes in the natural prairie landscape of western Canada. The objective of this research project is to evaluate landscape response to land use change by relating observed changes in the sedimentary record of a lake drainage basin to documented land use change that has occurred since the onset of settlement. A 52 cm lake sediment core was sectioned into 1 cm layers. The sediment was separated into allogenic and authigenic fractions using a wet chemical extraction technique. Close interval ²¹⁰Pb dating enabled the calculation of sediment and elemental influx rates. Prior to European settlement, erosion rates were low (< 0.1 Mg ha^− 1 year^− 1). In the 1910s, when the first settlers arrived in the area, erosion rates increased, and in the 1920s and 1930s, when the area of improved land rapidly increased and conditions were dry, erosion rates reached peaks of 1.5 and 2.2 Mg ha^− 1 year^− 1. Erosion rates in the latter part of the 20th Century range from 0.6 to 0.7 Mg ha^− 1 year^− 1. The composition of the allogenic fraction in the most recent, black sediment at the top of the core shows high concentrations of Ti and Zr, indicating a large contribution of topsoil to the allogenic fraction. In addition, elevated concentrations of Zn, Ni, Mo and U are likely explained by the application of phosphate fertilizers. Because of sediment deposition within the basin, e.g., on concave footslopes and on the valley floor, the erosion rates derived from the Thunstrom Lake core should be interpreted as net rates that likely mask values that are much higher locally within the basin. As a result, this study provides information on the erosional response of the prairie landscape to recent changes in land use at the scale of the Thunstrom Lake basin, but not necessarily on the sustainability of the soil as a resource, which would require information at the much smaller scale of the individual field.     

鄱阳湖湿地生态环境治理及其保护

鄱阳湖是我国最大的淡水湖泊,湖区湿地面积2698 km^2,其生态环境对调蓄洪水、调节气候、涵养水源、净化水质、维护生物多样性等方面具有重要的作用。长期以来由于人类不合理的开发利用,导致了鄱阳湖湿地面积和景观结构发生了很大变化,湿地生态环境也遭到严重破坏。在分析鄱阳湖湿地生态环境面临的主要问题及其成因的基础之上,提出了鄱阳湖湿地生态环境治理与保护的主要对策。