中国草地学报2026，Vol.48Issue(5)：55-67,13.DOI:10.16742/j.zgcdxb.20250422
长期放牧荒漠草原6种优势植物的光合气体交换特征
Photosynthetic Gas Exchange Characteristics of Six Dominant Plant Species in a Long-Term Grazing Desert Steppe
摘要
Abstract
The desert steppe of Inner Mongolia constitutes an important ecological barrier in northern China.Understanding the photosynthetic efficiency of dominant species and their response to long-term dif-ferent grazing intensities is of great significance for elucidating how this ecosystem adapts to human activi-ties and climate change.This study was conducted in the Stipa breviflora desert steppe with a 20-year graz-ing history.Net photosynthetic rate(Pn),stomatal conductance(Gs),transpiration rate(Tr),and intercel-lular CO2 concentration(Ci)were measured for six dominant plant species under four different grazing inten-sities.The results showed that:(1)among the six dominant species in the desert steppe,Convolvulus ammannii exhibited the highest Pn,Gs,and Tr.Regarding the overall effect of grazing intensity,the val-ues of Pn,Gs,Tr,and Ci under light grazing treatment were significantly higher than those under heavy grazing(P<0.05),showing a pattern of stimulation under low grazing intensity and impairment under high grazing intensity;(2)From the perspective of plant photosynthetic pathway,C4 species generally showed higher Pn,Gs,and Tr than C3 species,indicating that C4 plants have stronger photosynthetic capacity and greater environmental adaptability in the desert steppe ecosystem;(3)In terms of different life forms,forbs had the highest Pn,Gs,and Tr,while subshrubs had the lowest.Moreover,as grazing intensity increased,forbs remained relatively stable,showing stronger grazing tolerance,whereas subshrubs exhib-ited greater fluctuations and were more sensitive to changes in grazing intensity.In summary,among the six dominant species in the desert steppe,C.ammannii has exhibited the strongest photosynthetic capac-ity.Grazing intensity,photosynthetic pathway,and life forms jointly shaped the adaptive strategies of dominant species in response to grazing disturbance in the desert steppe.关键词
荒漠草原/放牧强度/光合气体交换/C3、C4植物/生活型Key words
Desert steppe/Grazing intensity/Photosynthetic gas exchange/C3 and C4 plants/Life form分类
农业科技引用本文复制引用
杜丽娟,阿拉坦其其格,刘仰乔,殷欣茹,张灿浩,康萨如拉..长期放牧荒漠草原6种优势植物的光合气体交换特征[J].中国草地学报,2026,48(5):55-67,13.基金项目
内蒙古自治区自然科学基金项目(2025MS3031) （2025MS3031）
