Effect of different years of alfalfa planting on available potassium and available nitrogen content in soil
The studying measured the content of available potassium and available nitrogen in the soil under different planting years of alfalfa,and analyzed their changes in the protoplasm soil and in the vertical tilth of the planting soil,and rhizosphere and non-rhizosphere in the soil.The results showed that the longer planting years of alfalfa had greater impact on potassium and nitrogen content in the soil,the potassium and nitrogen content in the topsoil was on the vertical decline,and the potassium and nitrogen content in rhizosphere and nonrhizosphere soil were obviously different under the same planting years,and the contents of potassium and nitrogen in the protoplasm soil and planting soil were obviously different.With the increasing of palnting years,the content of potassium and nitrogen were showed the trend of rise-decline-rise.The performance s of potassium content in overall ranked 2-year-old＞ 5 years old＞ 4 years＞ 3 years old＞ 1 year old＞ protoplasm soil.The performance of nitrogen content in overall ranked 2-year-old＞ 5 years old＞ 3 years old＞ 1 year old＞ 4 years ＞ protoplasm soil.In different growth period,the content of available potassium and available nitrogen were quite different,which was vertically increasing with increasing soil depth.The soil nutrients in every growth years showed a decreasing trend with topsoil accumulation,which the soil nutrients stored in the soil layer with 0～20 cm.
AlfalfaNumber of growth yearsavailable potassiumavailable nitrogen
NETL
NSTL
万方数据
维普
