泥沙沉降对水库中磷的空间分布影响

磷是水库富营养化的主要影响因子，对泥沙有很强的亲和性。为探究水库中磷的空间分布规律，针对泥沙沉降过程中对磷的吸附影响进行了模拟试验，研究了不同环境因素耦合作用下泥沙沉降对水库中磷分布的影响。此外，基于量纲分析及多元回归法建立了液相磷浓度垂向分布公式。结果表明：泥沙沉降过程中对磷的吸附导致液相磷的垂向分布呈上浓下稀的趋势。泥沙粒径越小、含沙量越高、水深越大，则液相磷元素的浓度梯度越大，垂向分布越不均匀。液相磷垂向分布公式表明，液相磷浓度梯度与含沙量的1/4次幂、泥沙粒径的-2/3次幂和水深的1/3次幂成正比，液相磷浓度最小值与含沙量的-1/20次幂、泥沙粒径的1/10次幂和水深的-1/10次幂成正比。公式计算值与试验数据基本吻合，表明该公式对研究水库磷元素的空间分布有重要参考意义。

Influence of sedimentation on the spatial distribution of phosphorus in reservoirs

Phosphorus is the main indicating factor of reservoir eutrophication and has strong affinity to sediment. In order to explore the spatial distribution law of phosphorus in reservoirs, a simulation test on the effect of sedimentation on phosphorus adsorption was carried out under the coupling action of different environmental factors. Besides, the formula for calculating vertical distribution of phosphorus concentration in liquid phase was established based on dimensional analysis and multiple regression method. The results show that the vertical distribution of liquid phase phosphorus tends to be thicker at the top and thinner at the bottom of the reservoir due to phosphorus adsorption during sedimentation. The smaller the particle size, the higher the concentration of sediment and the deeper the water depth, the greater the concentration gradient and the more inhomogeneous the vertical distribution of phosphorus in liquid phase. The vertical distribution formula of liquid phase phosphorus shows that the gradient of liquid phase phosphorus concentration is proportional to 1/4 power of sediment concentration, -2/3 power of sediment particle size and 1/3 power of water depth, and the minimum value of liquid phase phosphorus concentration is proportional to -1/20 power of sediment concentration, 1/10 power of sediment particle size and -1/10 power of water depth. The calculated results are in good agreement with those of the simulation test, indicating that the derived formula is applicable to the study of phosphorus distribution in reservoirs.