摘要
【目的】探究土壤磷素淋失临界值与土壤基本理化性质的关系。【方法】选取山西省总覆盖面积达88.51%的褐土、栗褐土、中性粗骨土、黄绵土、潮土5种典型土壤作为供试土壤,通过室内模拟试验分析土样的有机质量、机械组成、活性铁量、活性铝量、Olsen-P量、CaCl_(2)-P量。在土样中加入不同梯度的KH_(2)PO_(4)溶液,达到磷素平衡状态后分别测定土样的Olsen-P、CaCl_(2)-P量,根据Olsen-P量与CaCl_(2)-P量的关系方程分析土壤磷淋失的临界值。【结果】褐土、栗褐土、中性粗骨土、黄绵土和潮土的磷淋失临界值分别为73.5、70.0、23.3、39.3、61.4 mg/kg。供试土壤磷淋失临界值与黏粒量和活性铁量存在显著的负相关,但与有机质量和粉粒量的相关性则不显著。【结论】山西省5种主要土壤的磷淋溶潜力由大到小分别为:中性粗骨土>黄绵土>潮土>栗褐土>褐土,土壤黏粒量与活性铁量可以作为评估土壤磷淋失风险的主要土壤理化指标。
【Objective】Phosphorus(P)leaching from soils is not only an environmental concern but also a financial loss to farmers.Understanding the mechanisms underlying mobility of P in different soils is essential to alleviating its loss to surface runoff and leaching to groundwater.【Method】We studied the physical and chemical properties of typical soils in Shanxi province,including chestnut-cinnamon soil,regosol soil,loessial soil and fluvo-aquic soil,which combine to cover 88.51%of the land surface across the province.For each soil,we measured its organic matter,particle size in the range of>0.002 mm,0.002~0.05 mm and 0.05~2 mm,texture,active Fe(Al),Olsen-P and CaCl_(2)-P.Soluble P at different concentrations was added to each soil,and it was allowed to reach equilibrium.The contents of Olsen-P and CaCl_(2)-P were then determined using NaHCO_(3) and CaCl_(2),and the threshold that resulted in P starting to leach was calculated from the relationship between Olsen-P and CaCl_(2)-P.【Result】The critical P content beyond which P leached is 73.50 mg/kg for cinnamon soil,7.0 mg/kg for chestnut-cinnamon soil,23.30 mg/kg for neutral regosols soil,39.4 mg/kg for loessial soil and 61.36 mg/kg for fluvo-aquic soil.The critical Olsen-P content in all soils increased with the increase in organic matter content but not significantly(p>0.05).Logarithm of the critical Olsen-P content is significantly correlated to the logarithm of clay and active Fe content(p<0.05),but insignificantly correlated to the logarithmic soil organic matter and silt contents(p>0.05).【Conclusion】Vulnerability of the main five soils to P leaching is ranked in the order of neutral regosol soil>loessial soil>fluvo-aquic soil>chestnut-cinnamon soil>cinnamon soil.Clay and active Fe contents are the edaphic factors affecting P leaching the most.
作者
李丽君
霍晨
刘平
霍晓兰
马琳杰
惠薇
LI Lijun;HUO Chen;LIU Ping;HUO Xiaolan;MA Linjie;HUI Wei(College of Resource and Environment,Shanxi Agricultural University,Taiyuan 030031,China;Laboratory of Soil Environment and Nutrient Resources of Shanxi Province,Taiyuan 030031,China;College of Bioengineering,Shanxi University,Taiyuan 030006,China)
出处
《灌溉排水学报》
CAS
CSCD
北大核心
2022年第12期75-80,共6页
Journal of Irrigation and Drainage
基金
国家重点研发项目(2016YFD0800105-5)。
关键词
山西土壤
土壤理化性质
土壤磷素
淋溶突变点
Shanxi soil
soil physical and chemical properties
soil phosphorus
change-point
