土壤调理剂对冷浸田土壤特性及水稻生长的影响

冷浸田因长期受冷泉水浸渍,土体封闭,通气不良,土壤Eh值和有效养分低下,水稻产量偏低。本研究以单施化肥为对照,设置增施生物稻糠、脱硫灰、石膏、过氧化钙和硅钙肥处理,通过田间小区试验和定期观测,探究了不同土壤调理剂对冷浸田土壤特性及水稻生长的影响。结果表明:与CK处理比较,施用生物稻糠和石膏土壤活性还原物质含量分别降低了52%和30%,从而提高了土壤的氧化性能;土壤细菌数分别提高200%和96%,真菌数分别下降16%和10%,进而提高土壤供氮能力。而施用脱硫灰和石膏调节了土壤养分,土壤有效磷含量均增加83%,速效钾含量分别增加50%和13%,水稻叶绿素含量分别提高3%和5%。施用石膏、生物稻糠和脱硫灰水稻分别增产13.0%、10.1%和5.1%。研究认为,施用土壤调理剂能消减冷浸田还原物质毒害,提升土壤微生物活性,提高土壤养分供应,促进水稻增产,并以生物稻糠、石膏和脱硫灰效果最佳。

Effects of Amendments on Soil Properties and Rice Growth in Cold Waterlogged Paddy Field

The effect of different modifiers, such as potassium dihydrogen phosphate, calcium carbonate, sodium silicate, homemade plant ash and homemade biochar on immobilization in copper contaminated soil was investigated respectively, and the immobilization mechanism was clarified through analyzing heavy metal fractions by using modified BCR method and X-ray diffraction(XRD). The results showed that, the best dosing quantity(mass ratio) of the five modifiers was 30.3%,21.5%,27.8%,48.9%,12.4%,respectively, and the amount of soluble Cu in soils decreased and residual Cu increased rapidly when modifiers were added in soils. Among them the plant ash made by ourselves which can improve the soil pH and generate precipitation with copper was the most effective one to reduce the Cu availability, the use of plant ash reduced the amount of available and soluble Cu about 53% and 49.2% respectively, while increased the residual one about 4.7 times to the original soils.