稻壳生物炭对土壤养分、玉米产量及氮素利用率的影响

Effects of Rice Husk Biochar on Maize Yield and Soil Physico-chemical Properties

目的:研究不同添加量生物炭对玉米产量和土壤养分的影响。方法:以稻壳生物炭为材料,开展玉米田间试验。设置空白对照CK、不施生物炭BC0、生物炭施用量为5、10、20、30、40 t/hm^2,分别记为BC5、BC10、BC20、BC30、BC40。结果:当生物炭添加量处于5~40 t/hm^2之间时,随着生物炭施用量的增加,玉米产量先增加后下降,当生物炭施用量为30 t/hm^2时,与单施化肥处理相比,玉米产量提高31.41%,氮素利用率提高85.15%。当生物炭施用量为40 t/hm^2时,玉米产量比30 t/hm^2时略有下降,同时氮素利用率下降1.48%。生物炭添加量从5 t/hm^2增加到30 t/hm^2,土壤全氮含量提高21.31%~56.56%;土壤有机质提高0.54%~69.26%,土壤碱解氮和速效钾分别提高1.19%~33.08%和24.31%~122.86%,土壤速效磷随生物炭用量提高变化不明显。结论:生物炭还田能提高土壤养分并促进作物增产,当生物炭施用量为30 t/hm^2时,对玉米增产效果最好。

Objective:To study the effects of different amounts of biochar on corn yield and soil fertility.Methods:Rice husk biochar was used as the material to carry out field experiments on maize.The biochar dosage was set as 5,10,20,30,40 t/hm^2,which were denoted as BC5,BC10,BC20,BC30,and BC40,respectively.Results:The results showed that when the amount of biochar was between 5-30 t/hm^2,with the increase of biochar application,the yield of maize increased gradually,and the yield increase ranged from 6.73%to 31.41%.However,when the amount of biochar applied reached 40 t/hm^2,corn yield decreased slightly.In addition,when the amount of biochar added is 5-30 t/hm^2,the nitrogen utilization rate is increased by 28.50%-85.15%.When the biochar application rate was 40 t/hm^2,the nitrogen utilization rate decreased by 1.48%.With the increase of biochar addition,the total nitrogen content of soil increased by 21.31%-56.56%,the pH increased by 0.14-0.63 units,and the organic matter increased by 0.54%-69.26%.The increase rates of alkaline nitrogen and available potassium were 1.19%-33.08%and 24.31%-122.86%,respectively.Soil available phosphorus did not change significantly with the increase in biochar consumption.Conclusion:It is showed that biochar returning to the field can increase soil nutrients and promote crop yield increase.When the application rate of biochar is 30 t/hm^2,the yield increase effect is the best.