[Influence of rainwater harvesting and soil anti-seepage on soil water infiltration, distribution and use efficiency in hilly orchard.].

Rainwater harvesting and soil anti-seepage technology is a new technology based on the ridge film mulching and furrow rainwater harvesting. To explore the application effects of rainwater harvesting and soil anti-seepage technology, four different treatments including control (CK), loessal soil with compacted anti-seepage treatment (L), red clay with anti-seepage treatment (R), and red clay with compacted anti-seepage treatment (R) were set up in a "Fuji" hillside orchard in Mizhi Demonstration Station of northern Shaanxi Province. Soil bulk density, stable infiltration rate, soil water content, fruit quality and yield, and water use efficiency were measured. Results showed that R had the best anti-seepage efficiency with the highest bulk density (1.61 g·cm), the minimum water holding capacity, and the least stable infiltration rate (0.02 mm·min). The empirical formula of Kostiakov equation was suitable for describing water infiltration characteristics. Throughout the growing season, soil moisture for 0-60 cm soil depth in the rainwater harvesting ditch could be improved by the different anti-seepage treatments. R had the highest soil water content all the time and could satisfy the suitable water content standard for growth and development of apple trees in the dry season. Under the anti-seepage treatment, there was an "low humid layer" with 20-30 cm of soil layer under 60 cm soil depth, but the variation tendency of soil water content from "low humid layer" to 200 cm soil layer was stable and slightly higher than that in CK. Rainwater harvesting and soil anti-seepage treatments could increase fruit yield and water use efficiency, and improve the quality of fruit. Compared with that in CK, the fruit yield, the rate of good fruit, and water use efficiency of R treatment increased by 19.2%, 26.5%, and 24.5%, respectively. Therefore, rainwater harvesting and soil anti-seepage technology was recommended as the effective agricultural measurement in the apple production in loess hilly areas of northern Shaanxi Province.