Nitrogen, phosphorus and potassium recycling in an agroforestry ecosystem of Huanghuaihai Plain: with Paulownia elongata intercropped wheat and maize as an example

Ｎｉｔｒｏｇｅｎ，ｐｈｏｓｐｈｏｒｕｓａｎｄｐｏｔａｓｉｕｍｒｅｃｙｃｌｉｎｇｉｎａｎａｇｒｏｆｏｒｅｓｔｒｙｅｃｏｓｙｓｔｅｍｏｆＨｕａｎｇｈｕａｉｈａｉＰｌａｉｎ：ｗｉｔｈＰａｕｌｏｗｎｉａｅｌｏｎｇａｔａｉｎｔｅｒｃｒｏｐｐｅｄｗｈｅａｔａｎｄ...

Nitrogen, phosphorus and potassium recycling in an agroforestry ecosystem of Huanghuaihai Plain: with Paulownia elongata intercropped wheat and maize as an example

The studies show that in the whole community, P isdeficient, and N and K are basically balanced. N, P and K areaccumulated in plant tissues and litters, but depleted in soil. Nand P contents in surface soil(0-20 cm) are the main factorsafficting crop growth, and P contents in 20-80 cm soil layer is themajor affecting Paulownia elongate growth. The absorptioncoefficients of N, P and K in the communities are 0.078, 0.014 and0.052 respectively, their utilization coefficients are 0.95, 0.90and the recycling coefficients are 0.042, 0.05 and 0.063respectively.