黄土丘陵区仁用杏园不宜间作沙打

 〗在陕北黄土丘陵沟壑区对清耕和间作沙打旺(Astragalus adsurgens)6年、4年、2年仁用杏园0~500 cm土层土壤水分、有机质、全氮、全磷、速效氮、速效磷、速效钾含量及树体生长状况进行了测定，结果表明，间作沙打旺，除了在秋季提高了0~100 cm土层土壤水分以外，在春季、夏季和秋季均显著降低了0~500 cm土层土壤水分，且间作沙打旺年限越长，降低越显著。间作沙打旺提高了0~100 cm土层土壤有机质和全氮含量，间作年限越长效果越显著，但对100 cm土层以下的土壤有机质和全氮无显著影响。间作沙打旺对土壤全磷含量无显著影响。间作沙打旺显著降低了土壤速效养分含量，其中速效氮降低深度达500 cm土层，速效磷、速效钾达300 cm土层，且间作年限越长，降低越显著。间作沙打旺显著削弱了树体的长势，降低了坐果率和杏仁产量。间作沙打旺存在着与仁用杏争水争肥的矛盾，黄土丘陵沟壑区仁用杏园不宜间作沙打旺。

Astragalus adsurgens Is not Suitable Interplant in Armeniaca vulgaris × A. Sibirica Orchard in Loess Hilly and Gully Region

The experimentation of interplant Astragalus adsurgens in Armeniaca vulgaris×A. sibirica orchard had been done in loess hilly and gully region of northern Shaanxi. The moisture, organic matter, total N, total P, available N, available P, available K of 0-500 cm soil layers and the growth status of A.vulgaris×A. sibirica of clean tillage, interplant six years, interplant four years and interplant two years had been determined. The results showed that the soil moisture of interplant As. adsurgens increased in 0-100 cm soil layer in autumn, but the soil moisture of the treatments of interplant As. adsurgens reduced significantly in springtime, summertime and autumn in 0-500 cm soil layer, and the soil moisture reduced obviously as interplant years increasing. In 0-100 cm soil layers, organic matter and total N of the treatments of interplant As. adsurgens were higher than clean tillage, and increased obviously as interplant years increasing, but the soil organic matter and total N under 100 cm soil layers weren^,t significant difference than clean tillage. Between the treatments of interplantAs. adsurgens and clean tillage, soil total P didnt have significant difference. Soil available N, available P and available K of the treatments of interplant As. adsurgens were significant lower than clean tillage, soil available N reduced from 0 cm to 500 cm soil layers, soil available P and available K reduced from 0 cm to 300 cm soil layers, and the content of available N, available P and available K in soil decreased obviously as interplant years increasing. The A. vulgaris×A. sibirica growth of the treatments of interplant As. adsurgens were significant weaker, and fruit set percentage and the almond yield were significant lower than clean tillage. Between As. adsurgens andA. vulgaris×A. sibirica there were a contention for water and nutrient, A. vulgaris×A. sibirica orchard wasn^,t suitable interplant As. adsurgens in loess hilly and gully egion.