坡向对切挖边坡土壤钾素特征的影响

Influence of slope aspect on soil potassium characteristics of cut slopes

摘要:

为探究切挖边坡土壤钾素及其组分的空间分布规律，采用野外采样和实验室分析相结合的方法，以四川省阿坝州松潘县川黄高速公路的切挖边坡为研究对象，对比不同坡向间土壤各形态钾素含量的差异，分析不同形态钾素与土壤理化性质的相关性，明确土壤有效钾的影响因素.结果表明：土壤水溶性钾、非特殊吸附钾、特殊吸附钾、速效钾和非交换性钾含量均表现为阳坡>阴坡，而土壤矿物钾和全钾含量则表现为阳坡<阴坡；土壤所有形态钾素含量均表现为半阳坡>半阴坡.土壤非特殊吸附钾、特殊吸附钾和速效钾与土壤pH、全氮、碱解氮均达到显著或极显著正相关.土壤pH是影响切挖边坡土壤有效钾的主要因素，水溶性钾、非特殊吸附钾对切挖边坡土壤有效钾的贡献较大.

Abstract:

In order to explore the spatial distribution law of soil potassium and its components in excavated slopes, a combination of field sampling and laboratory analysis was used. The cut slopes of Chuanhuang Expressway in Songpan County, Aba Prefecture, Sichuan Province were selected as the research objects, the differences in soil potassium content between different slope aspects were compared, and the correlation between different forms of potassium and soil physical and chemical properties was analyzed, the influencing factors of soil available potassium were clarified. The results showed that the contents of soil water-soluble potassium, non-specially adsorbed potassium, specially adsorbed potassium, rapidlyavailable potassium and non-exchangeable potassium in the soil were all in the order of sunny slope > shady slope, while soil mineral potassium and total potassium contents were in the order of sunny slope< shady slope. The content of soil potassium in all forms showed the order of semi-sunny slope > semi-shady slope. Soil non-specially adsorbed potassium, specially adsorbed potassium and rapidly-available potassium was significantly or extremely significantly positively correlated with soil pH, total nitrogen, and alkaline hydrolyzed nitrogen. Soil pH is the main factor affecting soil available potassium, and water-soluble potassium and non-specially adsorbed potassium have a greater contribution to the soil available potassium of cut slopes.