鱼鳞坑与覆盖组合措施对陕北旱作枣园土壤水分的影响

Effects of scale-like pit and mulching measures on soil moisture of dryland jujube orchard in North Shaanxi Province, China

土壤水分是制约陕北红枣林健康生长的关键因子.通过土壤水分定位观测,研究不同鱼鳞坑与覆盖措施组合对陕北黄土丘陵区旱作枣园土壤水分的影响.结果表明：鱼鳞坑＋树枝覆盖、鱼鳞坑＋秸秆覆盖、鱼鳞坑无覆盖处理下0-180cm平均土壤含水量较裸地分别提高14.2%、9.4%、4.8%.不同处理在红枣生育期均能显著增加土壤表层（0-20cm）和主要根系层（20-100cm）土壤水分含量,其中,以鱼鳞坑＋树枝覆盖处理效果最为显著.不同组合措施条件下,次降雨量对土壤水分的影响深度主要集中在100cm以内,对深层土壤水分影响不显著.无覆盖鱼鳞坑措施在高、中、低水分状况下,各土层土壤水分与裸地无显著差异.在陕北旱作枣园,利用修剪枣枝进行覆盖在节省材料减少成本的同时,实现了保墒蓄水目标.

Soil moisture is a key factor affecting jujube growth in the semiarid Northern Shaanxi Province. The impacts of different engineering and mulching measures on soil moisture were investi- gated via in situ measurements in a typical dryland jujube orchard. The results showed that the mean soil moistures （0-180 cm） of scale-like pit ＋ branch mulching, scale-like scale ＋ straw mulching, and soil moisture of scale-like pit with no mulching were increased by 14.2%, 9.4%, and 4.8% than control, respectively. Different measures, especially for the scale-like pit ＋ branch mulching, significantly increased the soil moisture in the soil surface （0-20 cm） and the main root zone layer （20-100 cm） during the jujube growth stage. Individual precipitation events had great impacts on soil moisture in the 0-100 cm, while its effect on soil moisture in deep layers was not apparent. There was no significant difference among the soil moistures in different soil depths of scale-like pit with no mulching when compared with the control under high, medium, and low soil humidity conditions. This study indicated that using the clipped jujube branches as mulching could both save materials cost and achieve the goal of reserving more water in dryland jujube orchard in north Shaanxi Province.