水保所知识产出(1956---)知识库

针对黄土丘陵半干旱区林地土壤干化缺水严重的现象，利用 2012－2015 年 3 种覆盖措施下土壤水分定位实测数
据，探讨和分析全年覆盖措施对枣林休眠期土壤水分损失的影响。结果表明：休眠期是枣林地土壤水分损失的重要时期，
无覆盖枣林地土壤水分损失 85.64～92.34 mm，是同期降雨量的 2.12 倍。当地枣林地土壤水分损失的土层深度基本在 0～
200 cm 范围。在 0～200 cm 范围土壤垂直剖面上，休眠期 3 种覆盖措施下土壤水分损失均呈现随深度增加而均匀减少的
规律。休眠期 0～200 cm 土层秸秆覆盖、地膜覆盖和石子覆盖土壤水分总损失量分别较裸地减少 38.32、50.56、40.48 mm。
覆盖措施可以促进休眠期土壤水分向深层运移。

 To promote development of the forestry and alleviate soil water depletion in forest land, a better understanding of
the effects of different mulching patterns on soil moisture region, and further seeking reasonable soil conservation measures in
loess hilly-gully are paramount important. As the severe soil water depletion existed in forest land in the semiarid area of the
Loess Plateau, the soil water contents under 3 different mulching patterns in jujube orchard were measured using a neutron
probe (CNC100 DR, ChaoNeng, China) that had been calibrated using standard methods. From March 2012 to October 2015,
volumetric soil water content was measured 3 times per month. Measurements were made at the depth increment of 0.1 and 0.2
m in the 0–1 and 1–5 m soil layer, respectively. Meanwhile, the meteorological data were collected from meteorological
station near the experimental plots. The objective of this study was to investigate the effects of mulching patterns on soil water
loss in jujube orchard during dormancy period. The test plots were located at Yuanzhi Mount in Mizhi County, Shaanxi
Province. The test plots were selected in the 11-aged dwarf close planting jujube forest in October 2011. Three level-terraces
with similar slope and aspect were established on a hillslope. For each level-terrace, 4 treatments (straw mulching, plastic film
mulching, gravel mulching, and bare land) were set to explore the effects of mulching patterns on soil moisture. The plot scale
for 4 treatments was 2 m × 3 m and the area for each plot was thus 6 m2. The 20 cm wide and 5 m deep ditch all around each
plot was excavated for each plot. To isolate the surrounding soil water and root on the test plot, about 1 mm thick plastic was
used. There was no irrigation during the experiment. The thickness of the straw mulching was 10-12 cm, while the particle size
of gravel mulching was 0.5-1.0 cm with a thickness about 5 cm. In the plastic film mulching treatment plot, the terrain around
the trunk of jujube tree was lower than the surrounding soil. Furthermore, 1-2 cm gap between the trunk and the plastic film
was maintained to make sure that the ground water could flow into the trunk and infiltrate to the soil. The results indicated that
in growth period the soil water was at increasing stage on the whole, while the soil water exhibited a decreasing trend in
dormancy period. Hence, dormancy period occupied a dominant role in causing soil water loss in jujube orchard. The soil
water loss of bare land ranged from 85.64 to 92.34 mm, which was approximately 2.12 times greater than the rainfall of the
corresponding period. The depth of soil water loss could reach 200 cm in local jujube orchard. In the vertical direction of soil
profile (0-200 cm), the soil water loss gradually decreased with the soil depth. The soil water loss of straw mulching, plastic
film mulching, and gravel mulching was 38.32, 50.56, and 40.48 mm lower than that of bare land, respectively. Therefore,
mulching can promote the soil water movement from shallow to deep soil layer.