[Ecological effects of intercrops in comprehensive management patterns of hilly area plum orchard]

The study on the ecological effects of intercrops in four cropping patterns showed that with the increase of multiple cropping, the annual increase of soil organic matter, total N, total P and total K was 5% - 20%, 7% - 40%, 8% - 70% and 15% - 80%, respectively. Potato-soybean had the best benefit in soil and water conservation, followed by cole-peanut, potato-watermelon, and wheat. Compared with control, the average soil erosion module and runoff amount of 4 patterns were decreased by 44.19%, 39.55%, 38.24% and 37.56%, and 22.40%, 9.28%, 24.11% and 21.16%, respectively. Cole-peanut had the highest biomass, being averaged 100 276 kg . hm(-2) annually, and the second was potato-watermelon, with an average of 73 692 kg x hm(-2). Potato-watermelon had the highest productivity, which averaged 37 565 kg x hm(-2) annually, and the second was potato-soybean, averaged 25 934 kg x hm(-2). The efficiency of energy input was in order of cole-peanut, potato-watermelon, potato-soybean, and wheat, and the value was 2.96, 2.08, 2.01 and 0.96, respectively.