Road runoffs were sampled from five highways and five urban roads located in the New Juaben Municipality during the late storm events in the month of November 2014 and the early storm events in January 2015. A variety...Road runoffs were sampled from five highways and five urban roads located in the New Juaben Municipality during the late storm events in the month of November 2014 and the early storm events in January 2015. A variety of water quality parameters such as, pH, temperature, turbidity, electrical conductivity (EC), total suspended solids (TSS), total dissolved solids (TDS), aqueous concentrations of Chloride (Cl<sup>-</sup>), Phosphate (), Nitrate () and Sulphate () ions as well as the total concentrations of some selected heavy metals (Fe, Cu, Zn, Pb, Cd, Ni and Cr) were analysed for both periods. Although the results for the studied parameters, particularly the heavy metals varied for both sampling periods, the general trend indicated an increase in accumulation from November 2014 to January 2015. This was attributed to vehicular deposition as well as other natural and anthropogenic depositions on the road surfaces during the antecedent dry weather period between the two sampling months. The highest increase in pollutant loadings was associated with the heavy metals and some physico-chemical parameters such as TSS, TDS, EC and turbidity. Generally, EC, TDS, TSS and turbidity were above the permissible limits of the Environmental Protection Agency (EPA) of Ghana for both sampling periods. However, almost all the mean concentrations of heavy metals recorded for both road runoffs and the control samples were within the permissible limits of the Ghana EPA with some few exceptions.展开更多
Road prisms, such as cutslopes, fillslopes and road surfaces, can be important contributors of sediment to streams in forested watersheds. In this study rainfall simulations were carried out on cutslopes, fillslopes, ...Road prisms, such as cutslopes, fillslopes and road surfaces, can be important contributors of sediment to streams in forested watersheds. In this study rainfall simulations were carried out on cutslopes, fillslopes, road surfaces and forest grounds in hardwood forests of Lolet and Lat Talar, Iran. Water at intensity of 32.4 mm·h-1 was sprayed from a nozzle onto a square area of 0.48 m2. Runoff was collected by water gauge every 4 min and then runoff and sediment parameters were measured in each plot. Results indicated that on road surfaces, the runoff coefficient was 63.28%. On the cutslopes and fillslopes, the runoff coefficients were 35.14% and 10.23%, respectively. On the forest ground as a control, the runoff coefficient was 5.90%. Runoff volume was 2.73 mL·s^-1 on the road surfaces and 1.52 mL·s^-1 on cutslopes. On fillslopes the runoff volume was 0.44 mL·s^-1 and on the forest ground 0.25 mL·s^-1 The greatest rate of soil loss was found on the cutslope （280.79 g·m-2·h-1）. The total soil loss from the cutslopes was two times higher than that from the road surfaces and six times higher than that from the fillslopes. We conclude that cutslopes can be considered the main source of sediments in our study sites, but the function of road surface as a source of runoff generation is more important.展开更多
我国南方丘陵区密集分布的沟渠与水塘构成了复杂的沟塘系统,其与道路等基础设施共同重塑了流域水文过程。在乡村振兴和高标准农田建设持续推进的背景下,沟渠、水塘及道路的覆盖面积和空间结构将发生变化,进而影响小流域水沙输移过程。...我国南方丘陵区密集分布的沟渠与水塘构成了复杂的沟塘系统,其与道路等基础设施共同重塑了流域水文过程。在乡村振兴和高标准农田建设持续推进的背景下,沟渠、水塘及道路的覆盖面积和空间结构将发生变化,进而影响小流域水沙输移过程。鉴于此,以南方丘陵区典型小流域为研究对象,基于图论法构建了包含沟塘-道路的小流域汇流网络,利用Soil and Water Assessment Tool(SWAT)模型分析了沟塘-道路对小流域水沙输移的影响,并通过情景模拟提出了基于沟塘及道路优化的小流域水沙调控对策。结果表明:(1)沟塘-道路系统显著改变了小流域汇流网络结构特征,汇流网络的连通程度明显提高,其中汇流网络的节点数增加了786个,网络环度从2.00×10^(-7)增至3.01×10^(-7);(2)建模过程中纳入沟塘-道路系统后,子流域划分更符合实际地形特征,使径流模拟的R2和NSE分别提高了0.24和0.36,泥沙模拟的R2和NSE分别提高了0.17和0.22;(3)情景分析结果表明,沟渠植草可减少22.6%的径流和28.1%的泥沙输出,路面植草或铺设透水混凝土可分别削减22.8%和25.4%的泥沙输出,而塘内植草对径流和泥沙的拦截率分别为5.7%和3.2%。研究结果对于优化水土流失防控策略、加快生态清洁小流域建设具有重要意义。展开更多
文摘Road runoffs were sampled from five highways and five urban roads located in the New Juaben Municipality during the late storm events in the month of November 2014 and the early storm events in January 2015. A variety of water quality parameters such as, pH, temperature, turbidity, electrical conductivity (EC), total suspended solids (TSS), total dissolved solids (TDS), aqueous concentrations of Chloride (Cl<sup>-</sup>), Phosphate (), Nitrate () and Sulphate () ions as well as the total concentrations of some selected heavy metals (Fe, Cu, Zn, Pb, Cd, Ni and Cr) were analysed for both periods. Although the results for the studied parameters, particularly the heavy metals varied for both sampling periods, the general trend indicated an increase in accumulation from November 2014 to January 2015. This was attributed to vehicular deposition as well as other natural and anthropogenic depositions on the road surfaces during the antecedent dry weather period between the two sampling months. The highest increase in pollutant loadings was associated with the heavy metals and some physico-chemical parameters such as TSS, TDS, EC and turbidity. Generally, EC, TDS, TSS and turbidity were above the permissible limits of the Environmental Protection Agency (EPA) of Ghana for both sampling periods. However, almost all the mean concentrations of heavy metals recorded for both road runoffs and the control samples were within the permissible limits of the Ghana EPA with some few exceptions.
基金supported by a grant from the Basij Organizationfor Research, Science and Technology in Mazan-daran Province, Iran
文摘Road prisms, such as cutslopes, fillslopes and road surfaces, can be important contributors of sediment to streams in forested watersheds. In this study rainfall simulations were carried out on cutslopes, fillslopes, road surfaces and forest grounds in hardwood forests of Lolet and Lat Talar, Iran. Water at intensity of 32.4 mm·h-1 was sprayed from a nozzle onto a square area of 0.48 m2. Runoff was collected by water gauge every 4 min and then runoff and sediment parameters were measured in each plot. Results indicated that on road surfaces, the runoff coefficient was 63.28%. On the cutslopes and fillslopes, the runoff coefficients were 35.14% and 10.23%, respectively. On the forest ground as a control, the runoff coefficient was 5.90%. Runoff volume was 2.73 mL·s^-1 on the road surfaces and 1.52 mL·s^-1 on cutslopes. On fillslopes the runoff volume was 0.44 mL·s^-1 and on the forest ground 0.25 mL·s^-1 The greatest rate of soil loss was found on the cutslope （280.79 g·m-2·h-1）. The total soil loss from the cutslopes was two times higher than that from the road surfaces and six times higher than that from the fillslopes. We conclude that cutslopes can be considered the main source of sediments in our study sites, but the function of road surface as a source of runoff generation is more important.
文摘我国南方丘陵区密集分布的沟渠与水塘构成了复杂的沟塘系统,其与道路等基础设施共同重塑了流域水文过程。在乡村振兴和高标准农田建设持续推进的背景下,沟渠、水塘及道路的覆盖面积和空间结构将发生变化,进而影响小流域水沙输移过程。鉴于此,以南方丘陵区典型小流域为研究对象,基于图论法构建了包含沟塘-道路的小流域汇流网络,利用Soil and Water Assessment Tool(SWAT)模型分析了沟塘-道路对小流域水沙输移的影响,并通过情景模拟提出了基于沟塘及道路优化的小流域水沙调控对策。结果表明:(1)沟塘-道路系统显著改变了小流域汇流网络结构特征,汇流网络的连通程度明显提高,其中汇流网络的节点数增加了786个,网络环度从2.00×10^(-7)增至3.01×10^(-7);(2)建模过程中纳入沟塘-道路系统后,子流域划分更符合实际地形特征,使径流模拟的R2和NSE分别提高了0.24和0.36,泥沙模拟的R2和NSE分别提高了0.17和0.22;(3)情景分析结果表明,沟渠植草可减少22.6%的径流和28.1%的泥沙输出,路面植草或铺设透水混凝土可分别削减22.8%和25.4%的泥沙输出,而塘内植草对径流和泥沙的拦截率分别为5.7%和3.2%。研究结果对于优化水土流失防控策略、加快生态清洁小流域建设具有重要意义。
