Changes of Soil Fertility in Carya cathayensis Stands in Major Production Towns of Lin’an City

In 2008, 254 sampling point locations were established in Carya cathayensis stands in 7 towns of Lin’an, Zhejiang province. Soil determinations were carried out respectively in 2008, 2013 and 2018 on fertilities. The results showed that in 2018, the mean soil pH, organic carbon (SOC) content, hydrolysable nitrogen (N), phosphorus (P) and potassium (K) were 5.77, 19.52 g/kg, 74.96 mg/kg, 3.64 mg/kg and 99.93 mg/kg. Soil available N contents in the tested towns were significantly lower in 2018 than that in 2008 and 2013 (P<0.05). Soil available P was in serious shortage in tested towns. Soil available K content was the lowest in 2013 for all towns. Soil organic carbon and soil pH increased from 2008 to 2018, while hydrolysable N, available P and K decreased evidently.