Long term effects of biochar rate on soil available potassium content and potassium uptake in tobacco leaves
In order to investigate the long-term effects of biochar application rate on soil available potassium and tobacco potassium contents,two 5-year positional experiments were conducted in Bijie City,Guizhou Province.A randomized block design with single factor(biochar application rate at 0,5,15,20,40 t/hm2)was used in this study.The results showed that the increment in soil available potassium content was the highest in the first year after biochar application,which was 664.21%and 223.09%in two soils,respectively,and then stabilized,with a 5-year average of 82.36%and 39.80%,respectively.Compared with the control(no biochar),5-year average increase of available potassium content was 72.2%and 127.3%,251.1%and 22.3%,31.9%,47.6%for the two soils,respectively,when the biochar application rate was 15,20 and 40 t/hm2.In the meantime,total potassium content in tobacco leaves increased by 18.2%and 18.4%for the two soils,respectively.The results of these 5-year field experiments showed that the best biochar application rate was 15 t/hm2 for these two soils in order to increase the soil available potassium content and cured leaf potassium content.In conclusion,the application of biochar could significantly increase the soil available potassium content and cured leaf potassium content.
NETL
NSTL
万方数据
