Effects of warming on root exudative carbon inputs of dominant plants in alpine swamp meadows in the headwaters region of the Changjiang River
To explore the response patterns of root exudation carbon input rates in alpine swamp meadows to climate warming,we focused on the alpine swamp meadows in the Fenghuoshan region of the Qinghai-Xizang Plateau.During the peak growing season,the dynamic effects of different warming gradients(control group(CK);low warming treatment:2.7 ℃ warming(T1);high warming treatment:5.1 ℃ warm-ing(T2))on the root exudation carbon input rates were analyzed,and the results indicated that warming promoted the carbon secretion rate of unit root biomass,root length,and root surface area in dominant species,with significant differences existing among the treatments.The trend of unit root biomass and root surface area secretion rate was consistent for the three dominant species,specifically with T2＞T1＞CK.Warming significantly influenced the antioxidant enzyme activity in the roots of dominant species,which exhibited varied responses in root antioxidant enzyme activity to warming,generally enhancing super oxide dismutase activity and reducing catalase activity,while both reaching maximum or minimum values under high warming conditions.Under the T1 and T2 treatments,the biomass of the alpine marsh meadow increased by 72.39％and 81.81％,respectively,compared to CK.Warming significantly promoted the carbon input of root exudates and the transformation of soil nutrients.This effect inten-sified with the increasing magnitude of warming,with the conclusion that warming enhances the carbon secretion rate of the roots of three dominant species,thereby accelerating the nutrient cycling process in the region.
万方数据
维普
