摘要
选择不同供钾能力的烟-稻轮作区稻田,研究了烟杆还田对水稻产量、钾素吸收利用的影响及其替代钾肥的效果.结果表明:烟杆还田(2250 kg·hm^(-2))和施钾肥(K_2O 75kg·hm^(-2))均能增加水稻产量和地上部钾素的累积量,其中烟杆还田配施钾肥的增幅最大,低钾(土壤速效钾含量<100 mg·kg^(-1))、中钾(土壤速效钾含量100~150 mg·kg^(-1))和高钾(土壤速效钾含量>150 mg·kg^(-1))土壤的水稻分别增产13.3%、17.1%和13.5%.烟杆还田(St+NP)可以提高钾素吸收利用率和农学效率.但在水稻当前推荐施肥量(75kg·hm^(-2))条件下,烟杆还田配施钾肥(St+NPK)对钾肥(素)吸收利用率和农学效率无显著影响,说明当前推荐施钾量可能偏高.通过对烟杆还田替代钾肥的计算,发现还田烟杆可以替代10%~22%的化肥钾(K_2O),烟后晚稻在烟杆还田时钾肥施用可以减少7.2~16.5 kg·hm^(-2).因此在烟杆还田条件下,高钾田块可减少化学钾肥的施用,而中钾和低钾田块为稳定水稻产量和维持土壤钾素平衡,则应保证目前推荐钾肥量的投入.
Field trails were carried to study the effects of tobacco straw incorporation and potassium (K) fertilizer on rice yield, K uptake and use efficiency, and its substitute for K fertilizer under different paddy soil K levels in tobaccorice rotation areas. Results showed that both tobacco straw incorporation (2250 kg·hm^-2) and K fertilizer application (75 kg K2O ·hm^-2) could increase grain yield and aboveground K uptake of rice. The treatment of tobacco straw incorporation with K fertilizer (St+NPK) got the best effect on rice yield compared with the control (NP). In this treatment (St+NPK), rice yields were increased by 13.3%, 17.1% and 13.5% for lowK soil (available potassium content 〈 100 mg·kg^-1), middleK soil (available potassium content 100-150 mg·kg^-1) and highK soil (available potassium content 〉 150 mg·kg^-1), respectively, compared with NP. Tobacco straw incorporation (St+NP) could increase K fertilizer recovery efficiency and K fertilizer agronomic efficiency. Under the current practice of applying 75 kg K2O·hm^-2, St+NPK showed no significant effect on K fertilizer recovery efficiency and K fertilizer agronomic efficiency, demonstrating that the recommended rate of K fertilizer might be more than the actual demand of rice growth. More importantly, data of tobacco straw substitute for K fertilizer showed that tobacco straw incorporation could replace 10%-22% K fertilizer during rice growing season, i.e. K fertilizer could be reduced by 7.2-16.5 kg·hm^-2 for rice under the condition of tobacco straw incorporation. Therefore, it was suggested that straw incorporation could reduce the rate of K fertilizer for highK soil, but the current K fertilizer inputs (75 kg K2O·hm^-2) should be supplied to get high rice yield and maintain the soil potassium balance for lowK soil and middleK soil.
出处
《应用生态学报》
CAS
CSCD
北大核心
2016年第12期3969-3976,共8页
Chinese Journal of Applied Ecology
基金
安徽省烟草公司科技项目(20140551004)
安徽省农业科学院院长青年基金项目(14B0945)
公益性行业(农业)科研专项(201203013)资助~~
关键词
烟杆还田
水稻
养分吸收
烟杆钾
替代钾肥
tobacco straw returning
rice
nutrient absorption
straw potassium
substitute potassium.