Response of Macleaya cordata biomass and its distribution characteristics to nitrogen in the reclamation area of a coal mine
To study dynamic changes in biomass and total biomass allocation of Macleaya cordata at different growth stages and nitrogen application gradients,a two-year continuous nitrogen application experiment was conducted from 2020,and the growth adaptation characteristics of M.cordata in poor soil were revealed.Five nitrogen application levels were set up:CK(0 kg·ha-1),N1(75 kg·ha-1),N2(150 kg·ha-1),N3(225 kg·ha-1),and N4(300 kg·ha-1).The results were as follows:1)The shoot biomass,root biomass,and total biomass of M.cordata were significantly higher than those of CK,N1,and N2(P＜0.05).2)The root-shoot ratio of M.cordata varied in different years.The root-shoot ratio of all treatments in the first year were the lowest in June(0.04,0.12,0.09,0.15,and 0.16)and the lowest in August in the second year(0.20,0.18,0.08,0.06,and 0.10)in June and August 2021,and the root-shoot ratio of CK were higher than those of other treatments.3)In 2020,the stem-leaf ratio of N3 was significantly higher than that of other treatments in October(P＜0.05).The stem-leaf ratio of other treatments had no significant difference between months.The stem-leaf ratio of 2021 treatments increased gradually with the recovery time and peaked in November(2.82,1.19,1.23,1.89,and 2.05).In conclusion,225～300 kg·ha-1should be applied to M.cordata in coal mine reclamation areas to promote rapid colonization of M.cordata in poor soil.This study may provide a theoretical basis for the study of growth adaptability of M.cordata in nitrogen-deficient soil.
万方数据
维普
