内蒙古荒漠草原优势物种萌发期抗旱性评价OA

This study focused on dominant plant species from the natural desert grasslands of Inner Mongolia,with the aim of identifying species suitable for ecological restoration of mining dumps in arid regions.Seven dominant grassland species were selected as experimental materials.Based on drought-response mechanism during seed germination,a soil moisture gradient(2.56％–12.77％)was established to simulate drought stress.Germination rate,seedling growth parameters,germination index,simplified vigor index,and drought resistance index were measured.A comprehensive drought resistance evaluation system was developed using the membership function method.Key findings revealed that as water stress intensified,all measured indices(germination rate,growth status,germination index,vigor index,and drought resistance index)declined nonlinearly.Under severe drought(5.11％soil moisture),the germination rates of Lolium perenne and Melilotus officinalis were significantly higher than other species(P<0.05).Comprehensive evaluation ranked drought resistance in the following order:Lolium perenne>Melilotus officinalis>Setaria viridis>Elymus dahuricus>Medicago sativa>Astragalus adsurgens>Artemisia desertorum.The study demonstrated that Lolium perenne,Melilotus officinalis,and Setaria viridis exhibited strong drought tolerance and were recommended as pioneer species for mining-area revegetation.Additionally,5.11％soil moisture(40％of field capacity)was identified as the critical lower threshold for seed germination,providing a quantitative basis for water management strategies in ecological restoration of arid mining zones.