The effect of peach-soybean intercropping system with straw mulching on N and P losses, surface runoff in Dianchi Lake watershed mountain area, Yunnan province, China

¹ College of Horticulture and Landscape, Yunnan Agricultural University, Kunming 650201, China
² College of Resources and Environment at Yunnan Agricultural University, Kunming, P. R. China.

^* Corresponding author: ecolibo@126.com

Abstract

Field experiments were conducted with peach (local variety)-soybean intercropping system as an agro-forestry community. The results showed that the reduction rate of COD_cr losses were 24.31%, 50.50% and 65.19% respectively under the precipitation strength between 25mm d^-1 and 100 mm d^-1 with treatments of 36 kg plot^-1, 54 kg plot^-1 and 72 kg plot^-1 straw mulching. The reduction rate of NH₄⁺-N losses were 12.56%, 49.38% and 58.60%, respectively; The reduction rate of NO_3--N losses were 27.78%, 9.55% and 58.61%, respectively; The reduction rate of TN losses were 3.85%, 31.67% and 56.01%, respectively. The reduction rate of TP losses were 23.02%, 30.19% and 42.65%, respectively. The yields of soybean increased by 24.09%, 47.46% and 93.84%, respectively. Peach-soybean intercropping with straw mulching could decrease the runoff losses of nitrogen and phosphorus with time effect for reducing non-point sources pollution losses.