旱地苹果园环状深沟施肥综合效应初报

Integrated effects of annularity deep-ditch fertilizing on dryland apple

对旱地苹果园采用深沟施肥技术下的土壤物理性质、土壤水分、土壤养分和果树产量及生育状况进行了研究.结果表明:深沟施肥可明显改善果树生长的土壤环境,使40～80 cm土层容重降低6.1%～16.0%,土壤孔隙度增加23.0%～41.5%, 40～60 cm土层有机质增加0.77 g/kg,增幅达15.1%; 40～80 cm土层内,土壤有效氮比对照增加了11.4～15.8 mg/kg,提高21.9%～28.3%, 0～100 cm有效磷增加31.3 mg/kg,增幅41.3%;0～100 cm平均土壤含水量旱季比对照果园高4.3%,雨季高3.9%.深沟施肥促进树体新梢生长,深松后吸收根的长度和体积分别是对照的2.7倍和1.8倍;苹果单株产量和经济效益提高幅度分别为20.8%和24.0%.说明深沟施肥是旱地果园土壤水肥管理的一个行之有效的模式,值得苹果园大力推广.

In this paper,the technique of fertilizer application in deep ditches was adopted in dryland apple orchard, and its effects on the soil physical properties, soil moisture, soil nutrient, development of trees and yield were studied. Compared with CK（fertilizing at the depth of 20-30 cm）, the deep-ditch fertilizing （fertilizing at the depth of 40-60 cm） could improved the soil ecological conditions. At the profile of 40-80 cm, the deep-ditch fertilizing reduced the soil bulk density by 6.1%-16.0%, and increased the soil porosity by 23.0%-41.5%. The soil organic matter in the depth of 40-60 cm, the available nitrogen in the depth of 40-80 cm and the available phosphorus in the depth of 0-100 cm were increased by 15. 1%, 21.9%-28.3% and 41.3%, respectively. The average soil moisture in the depth of 0-100cm was 4.3% higher than CK in dry season, 3.9% higher in rainy season. The deep-ditch fertilizing accelerated the growth of new shoots and increased the absorption roots significantly. The length and the volume of absorption roots were 2.7 times and 1.8 times of CK respectively. Under the treatment of deep-ditch fertilizing, the yield and economic effect of individual tree was increased by 20.8% and 24.0% respectively. These results suggested that the deep-ditch fertilizing was an effective approach for soil water and fertility management in dryland apple orchards.