The single high-dose application of biochar to increase rice yield has been well reported.However,limited information is available about the long-term effects of increasing rice yield and soil fertility.This study was...The single high-dose application of biochar to increase rice yield has been well reported.However,limited information is available about the long-term effects of increasing rice yield and soil fertility.This study was designed to perform a 6-year field experiment to unveil the rice yield with time due to various biochar application strategies.Moreover,an alternative strategy of the Annual Low dose biochar application(AL,8×35%=2.8 t ha^(−1))was also conducted to make a comparison with the High Single dose(HS,22.5 t ha^(−1)),and annual Rice Straw(RS,8 t ha^(−1))amendment to investigate the effects on annual rice yield attributes and soil nutrient concentrations.Results showed that the rice yield in AL with a lower biochar application exceeded that of HS significantly(p<0.05)in the 6th experimental year.The rice yield increased by 14.3%in RS,10.9%in AL,and 4.2%in HS.The unexpectedly higher rice yield in AL than HS resulted from enhanced soil total carbon(TC),pH,and available Ca.However,compared to AL,liable carbon fraction increased by 33.7%in HS,while refractory carbon fraction dropped by 22.3%.Likewise,biochar characterization showed that more oxygen functional groups existed in HS than in AL.Decreasing inert organic carbon pools due to the constant degradation of the aromatic part of biochar in HS led to a lower soil TC than AL,even with a higher amount of biochar application.Likewise,the annual depletion lowered the soil pH and available Ca declination in HS.Based on the obtained results,this study suggested AL as a promising strategy to enhance rice productivity,soil nutrient enrichment,and carbon sequestration in the paddy ecosystem.展开更多
基金National Natural Science Foundation of China[grant numbers 42077032 and 41571241]National Key Technology Research and Development Program of the Ministry of Science and Technology of China[grant number 2015BAC02B01]+1 种基金We gratefully acknowledge the financial support from the China Scholarship Council[grant number 202106320251]Doctoral Rising Star Program of Zhejiang University.
文摘The single high-dose application of biochar to increase rice yield has been well reported.However,limited information is available about the long-term effects of increasing rice yield and soil fertility.This study was designed to perform a 6-year field experiment to unveil the rice yield with time due to various biochar application strategies.Moreover,an alternative strategy of the Annual Low dose biochar application(AL,8×35%=2.8 t ha^(−1))was also conducted to make a comparison with the High Single dose(HS,22.5 t ha^(−1)),and annual Rice Straw(RS,8 t ha^(−1))amendment to investigate the effects on annual rice yield attributes and soil nutrient concentrations.Results showed that the rice yield in AL with a lower biochar application exceeded that of HS significantly(p<0.05)in the 6th experimental year.The rice yield increased by 14.3%in RS,10.9%in AL,and 4.2%in HS.The unexpectedly higher rice yield in AL than HS resulted from enhanced soil total carbon(TC),pH,and available Ca.However,compared to AL,liable carbon fraction increased by 33.7%in HS,while refractory carbon fraction dropped by 22.3%.Likewise,biochar characterization showed that more oxygen functional groups existed in HS than in AL.Decreasing inert organic carbon pools due to the constant degradation of the aromatic part of biochar in HS led to a lower soil TC than AL,even with a higher amount of biochar application.Likewise,the annual depletion lowered the soil pH and available Ca declination in HS.Based on the obtained results,this study suggested AL as a promising strategy to enhance rice productivity,soil nutrient enrichment,and carbon sequestration in the paddy ecosystem.
