Effects of aeolian deposition on soil properties and crop growth in sandy soils of northern China

Soil erosion and sand deposition influence soil quality and crop productivity. A field experiment was conducted from 2000 to 2001 in the Horqin Sandy Land along a depth gradient of wind-deposited sand to investigate changes in soil and crop growth properties. Treatments were designated as control (no excess sand deposition), shallow sand deposit (4-6 cm), moderate sand deposit (10-16 cm), and deep sand deposit (29-40 cm). Results indicated that the deep sand deposit soil environment was significantly degraded, and crop growth and biomass were restrained. Compared to the control cropland, the deep sand deposit showed reductions in soil clay content (46-50%), organic matter (52-60%), total N (59-64%), total P (35%), available N (35-46%), available P (36-38%), and average soil moisture (24-44%). In addition, soil temperature was elevated by 1.3-2.5 degrees C, corn life cycle was advanced by 2 days, plant height was reduced by 6% and diameter by 13-15%, and above-ground biomass and seed yield decreased by 15-28% and 20-33%, respectively. Although the moderate sand deposit also had reduced soil clay content, nutrients and soil moisture, the reductions were significantly lower than in the deep sand deposit, and seed yield and above-ground biomass were significantly higher. Effects of the shallow sand deposition on soil properties, crop growth and seed yield were minor. Correlation analysis showed that both above-ground biomass and seed yield had a significant (P < 0.05) positive correlation with the soil clay content, silt, organic matter, total N and P, available N and P, and soil moisture, and a significant negative correlation with sand content and soil temperature. (C) 2007 Elsevier B.V All rights reserved.