Effects of biochar on root morphological traits of peanut and soil inorganic nitrogen in coal mining subsid-ence area under different drip irrigation methods
The reclamation of coal mining subsidence area is one of the challenges in coal mining area.We exam-ined the effects of different drip irrigation methods and biochar application rates on peanut yield in coal mining sub-sidence area.A split-plot design experiment was conducted with two irrigation methods(i.e.,film-mulched drip ir-rigation(M)and shallow buried drip irrigation(Q))as the primary plots,and three biochar application rates(0(B0),10(B10),and 20 t·hm-2(B20))as the subplots in 2021 and 2022.Root growth,dry matter,nitrogen ac-cumulation in dry matter,yield and yield components,and soil inorganic nitrogen content were measured.Com-pared with the shallow buried drip irrigation,the film-mulched drip irrigation significantly increased root length,root volume,root surface area,dry matter accumulation at pod filling stage,100-kernel mass,100-fruit mass,and pod yield,but decreased soil NH4+-N and NO3--N contents.Pod yield,100-kernel mass,and 100-fruit mass under the film-mulched drip irrigation were 14.9％,8.9％,and 6.3％higher than those under the shallow buried drip irri-gation,respectively.Root length(except at the seedling stage),root volume(except at the seedling and pod set-ting stages),root surface area(except at the seedling stage),dry matter accumulation at the pod filling stage,100-fruit mass,100-kernel mass,and grain yield initially increased and then decreased with increasing biochar ap-plication rates.The peak values were observed under the B10 treatment,the pod yield under which was 19.8％high-er than under the B0 treatment.Soil NH4+-N content(except at the seedling stage)decreased while soil NO3--N content(except the seedling stage)and plant N accumulation increased with increasing biochar application rates.Under MB 10 treatment,root length,root volume(except at pod setting stage),root surface area(except at seed-ling stage),dry matter accumulation at pod filling stage,100-fruit mass,100-kernel mass and yield were all opti-mal,with the yield being 38.8％higher than that under QB0 treatment.Peanut yield,100-kernel mass,and 100-fruit mass had a significant and positive correlation with total root length and root surface area.The 100-fruit mass was significantly and positively correlated with soil NH4+-N and NO3--N contents.In conclusion,the application of 10 t·hm-2 biochar combined with film-mulched drip irrigation promoted root growth of peanut,improved plant in-organic nitrogen absorption,increased dry matter accumulation,and finally increased yield.Our findings would pro-vide technical support and theoretical reference for land reclamation in coal mining subsidence areas.
国家科技期刊平台
NSTL
万方数据
