Structure and function of several intercropping ecosystems in newly built orchard
新建果园几种作物间种模式生态系统结构及功能研究

Sloping wildland is the important potential land resource in China. Structures and functions of five optimized models selected from more than 10 intercropping patterns in the newly built orchards in the uncultivated sloping field were analyzed in this paper. The results showed that organic matter was increased by 5-20%, total N by 7-40%, total P by 8-70%, and total K by 15-80% yearly. Considering its benefit in soil and water conservation, the intercropping model of peanut and autumn soybean was the best, and followed by spring soybean and autumn soybean, tomato and Chinese cabbage, cayenne and tomato, and drought rice and red turnip. Compared with the control, the average soil erosion module and runoff amount of the 5 models were decreased by 44.19%, 38.24%, 39.52%, 37.56%, 37.30%, and 22.40%, 9.28%, 24.11%, 21.60%, 15.93%, respectively. The intercropping model of cayenne and tomato had the highest biomass, and its annual biomass averaged 1,00,267 kg.hm-2. The biomass of intercropping model of peanut and autumn soybean was the second, and the annual value averaged 77,026 kg.hm-2. Intercropping model of peanut and autumn had the highest annual productivity, which averaged 15,619 kg.hm-2, and that of intercropping model of tomato and Chinese cabbage was the second, averaged 15,394 kg.hm-2. The efficiency of energy introjection was in order of cayenne and tomato, tomato and Chinese cabbage, peanut and autumn soybean, spring soybean and autumn soybean, and dry rice and red turnip, and their values were 3.06, 2.16, 2.15, 2.06, and 0.71, respectively.