汾河河岸带土壤氮、磷的时空分布规律及其影响因素研究

为明晰汾河临汾段河岸带土壤氮、磷时空分布规律及其影响因素,采用现场检测、空间分析及数理统计方法,探讨了自然河岸带及强人工干扰河岸带土壤氮、磷的化学计量学特征、时空分布特征及其与土壤、水文特性的相关性。结果表明:(1)各水期强人工干扰河岸带土壤TN、TP储量及其变异系数均大于自然河岸带,自然河岸带土壤氮、磷元素的生态化学计量存在弱稳态性;(2)汾河临汾段河岸带土壤TN、TP含量随枯水期—平水期—丰水期表现为先减小后增大的趋势,横向来看河岸带近岸土壤TN、TP含量大于远岸部分,土层深度方向上TN、TP含量随土层深度增加而减小;(3)河流水质、土壤容重和土壤孔隙度是影响汾河河岸带土壤TN含量的相关因子,土壤容重、土壤孔隙度和N/P是影响河岸带土壤TP含量的相关因子。研究结果表明汾河河岸带土壤氮分布与河流水文特性有一定的响应关系,土壤磷分布与河流水文特性无明显的响应关系。

Study on the Spatial and Temporal Distribution and Influencing Factors of Soil Nitrogen and Phosphorus in Riparian Zones of Fenhe River

In order to clarify the spatial and temporal distribution of soil nitrogen and phosphorus and their influencing factors in the riparian zones of Fenhe River, the purpose of this study was to discuss the stoichiometric characteristics, spatiotemporal distribution characteristics of soil nitrogen and phosphorus and their correlation with soil and hydrological characteristics in natural riparian zone and strong artificial-disturbance riparian zone. The results showed that: (1)There serves of total nitrogen (TN) and total phosphorus (TP) in the strong artificial-disturbed riparian zone were bigger than those in the natural riparian zone, and the coefficients of variation in natural riparian zone were smaller than those of the strong artificial-disturbed riparian zone. The ecological stoichiometry of nitrogen and phosphorus in soil of natural riparian zone were weakly stable in each water period. (2) As for the riparian zones in Fenhe River during each water period, the contents of TN and TP in the soil of riparian zones showed a trend of first decreasing and then increasing with the period to dry season-normal season-wet season. In the lateral direction along the riparian zone, the contents of nitrogen and phosphorus in the soil of near-bank part were significantly higher than those in the far-bank part. While the contents of TN and TP in the depth direction of the soil decreased with the increase of depth. (3) River water quality, soil bulk density and soil porosity were the correlation factors affecting soil TN content in riparian zones of Fenhe River, while soil bulk density, soil porosity and ratio of nitrogen and phosphorus were the correlation factors affecting soil TP content in riparian zones. The results showed that the distribution of soil nitrogen in riparian zones of Fenhe River had a certain response relationship with river hydrological characteristics, while the distribution of soil phosphorus had no obvious response relationship with the river hydrological characteristics.