Soil moisture condition and dry-layer development under Xi'an southern suburb apple orchard in rainy years

Through the determination and comparison of autumn and spring(for rainy years) soil moisture contents under 15-year old apple orchards in the southern suburb of Xi'an,a change in the moisture content within 0～6m depth of soil and the development of dry-layers were analyzed.It is shown that soil moisture within 2～4m soil depth is 8%～10% in spring indicating developed dry-layers of soil.Moisture content within 2～4m soil depth in autumn is more than 23%,far higher than that in spring showing that dry-layers have dispeared.Therefore soil moisture of dry-layer developed in the spring can be recovered rapidly to 5m deep in rainy years.