Effects of W-OH stabilizer on soil water percolation and nitrate nitrogen leaching

ZHANG Guan-hua;HU Jia-jun;Soil and Water Conservation Department,Yangtze River Scientific Research Institute,Research Center on Mountain Torrent & Geologic Disaster Prevention of Ministry of Water Resources;Changjiang Water Resources Commission of the Ministry of Water Resources;

W-OH soil stabilizer;;water percolation;;nitrate nitrogen;;nutrient leaching;;slope cropland of purple soil

Combing with natural rainfall observation,a pot experiment was conducted to study the effects of different W-OH concentration( 1%,3% and 5%) on soil water percolation and nitrate nitrogen leaching in cropland( soybean,maize,and garlic). The results showed that both precipitation and crop type had influences on water retention of W-OH. For light and moderate rain,3% treatment had the lowest leakage in maize pots showing the most significant water retention effect. For heavy rain and rainstorm,the water retention effect of W-OH was directly proportional to its spraying concentration. The water retention effect of W-OH in soybean and garlic pots was not affected by precipitation,and the influence law of soil water leakage by W-OH was similar. Compared with CK( without W-OH),water leakage increased with W-OH concentration increasing.The fertilizer retention effect of W-OH was proportional to its spraying concentration at the initial stage of crop growth and tended to be stable with subsequent rainfall leaching. During the observation period,both 3% and 5% treatments effectively reduced the nitrate leaching loss for maize and garlic pots,1% treatment also effectively reduced nitrate leaching loss for soybean pots.