为揭示生活污水补给影响下排水沟渠氮、磷滞留特征,以合肥市城郊结合部的关镇河支渠为对象,以NH4Cl和KH2PO4为添加营养盐,以Na Cl为保守型示踪剂,开展5次现场示踪试验.在此基础上,利用OTIS(one-dimensional transport with inflow and s...为揭示生活污水补给影响下排水沟渠氮、磷滞留特征,以合肥市城郊结合部的关镇河支渠为对象,以NH4Cl和KH2PO4为添加营养盐,以Na Cl为保守型示踪剂,开展5次现场示踪试验.在此基础上,利用OTIS(one-dimensional transport with inflow and storage)模型估算D(扩散系数)、A(渠道过水断面面积)、As(暂态存储区断面面积)、α(暂态存储交换系数)、λ(主流区溶质一阶吸收系数)和λs(暂态存储区吸收系数);并利用营养螺旋原理,计算营养盐的Sw(吸收长度)、Vf(吸收速度)和U(吸收速率)等.结果表明:1As/A具有随流量减小而增大的变化特征,平均值为0.35;5次试验得到的α均处在10-3数量级水平,平均值为2.49×10-3s-1.2Sw-NH4和Sw-PO4(分别表示NH4-N和PO4-P的Sw,下同)均较大,最大值分别达934 020、47 518 m,意味着关镇河支渠已基本不具备氮、磷滞留能力;而Sw-NH4和Sw-PO4均不同程度地出现负值,表明该支渠还具有"源"的作用.3Vf-NH4与河水平均深度、渠道流量均呈显著负相关,Vf-PO4和U-PO4与渠道水面宽度均呈显著正相关.4NH4-N和PO4-P的营养螺旋指标与其相应质量浓度背景值无明显相关性.展开更多
A study was conducted to examine the effect of heavy metals (Cu, Pb, Zn and Cd in combination or alone) on the equilibrium and kinetics of phosphorus (P) retention in typic udic ferrisols by using both equilibrium and...A study was conducted to examine the effect of heavy metals (Cu, Pb, Zn and Cd in combination or alone) on the equilibrium and kinetics of phosphorus (P) retention in typic udic ferrisols by using both equilibrium and flow techniques. Fourteen soil samples with varying artificial contamination of Cu, Pb, Zn and Cd were prepared. Heavy metal pollution led to increases in retention capacity and maximum buffering capacity (MBC) of soil P. The rate of P retention was also increased and the time to reach equilibrium was advanced by heavy metals addition. The Elovich equation provided a satisfactory description of the P kinetic data. The influence of heavy metals on P retention was in the order of Pb>Cu>Zn, with greater effect in multiple metal pollution. These findings suggested that heavy metal pollution caused an increase in P fixation and thus a decline in P availability. Therefore, indirect influences of heavy metal contamination on soil nutrients may need more consideration when determining overall impact of heavy metals on soil environment.展开更多
文摘为揭示生活污水补给影响下排水沟渠氮、磷滞留特征,以合肥市城郊结合部的关镇河支渠为对象,以NH4Cl和KH2PO4为添加营养盐,以Na Cl为保守型示踪剂,开展5次现场示踪试验.在此基础上,利用OTIS(one-dimensional transport with inflow and storage)模型估算D(扩散系数)、A(渠道过水断面面积)、As(暂态存储区断面面积)、α(暂态存储交换系数)、λ(主流区溶质一阶吸收系数)和λs(暂态存储区吸收系数);并利用营养螺旋原理,计算营养盐的Sw(吸收长度)、Vf(吸收速度)和U(吸收速率)等.结果表明:1As/A具有随流量减小而增大的变化特征,平均值为0.35;5次试验得到的α均处在10-3数量级水平,平均值为2.49×10-3s-1.2Sw-NH4和Sw-PO4(分别表示NH4-N和PO4-P的Sw,下同)均较大,最大值分别达934 020、47 518 m,意味着关镇河支渠已基本不具备氮、磷滞留能力;而Sw-NH4和Sw-PO4均不同程度地出现负值,表明该支渠还具有"源"的作用.3Vf-NH4与河水平均深度、渠道流量均呈显著负相关,Vf-PO4和U-PO4与渠道水面宽度均呈显著正相关.4NH4-N和PO4-P的营养螺旋指标与其相应质量浓度背景值无明显相关性.
基金Project jointly supported by the National Natural Science Foundation of China (No. 49771048) and theLaboratory of Material Cyc
文摘A study was conducted to examine the effect of heavy metals (Cu, Pb, Zn and Cd in combination or alone) on the equilibrium and kinetics of phosphorus (P) retention in typic udic ferrisols by using both equilibrium and flow techniques. Fourteen soil samples with varying artificial contamination of Cu, Pb, Zn and Cd were prepared. Heavy metal pollution led to increases in retention capacity and maximum buffering capacity (MBC) of soil P. The rate of P retention was also increased and the time to reach equilibrium was advanced by heavy metals addition. The Elovich equation provided a satisfactory description of the P kinetic data. The influence of heavy metals on P retention was in the order of Pb>Cu>Zn, with greater effect in multiple metal pollution. These findings suggested that heavy metal pollution caused an increase in P fixation and thus a decline in P availability. Therefore, indirect influences of heavy metal contamination on soil nutrients may need more consideration when determining overall impact of heavy metals on soil environment.
