Effects of water and soil microorganisms on the growth traits of Albizia kalkora and Leucaena leucocephala in a dry-hot valley

Vegetation restoration is an effective way for ecological restoration in the dry-hot valley, and many alien species are introduced along with natural vegetation restoration. In order to compare the responses of native and alien species to water and microorganisms, the native Albizia kalkora and alien Leucaena leucocephala were selected as our research objects, and the effects of water and soil microorganisms on the growth and development of the two plants were studied by soil water control and soil microbial inoculation under climate chamber conditions. The results were as follows:(1)Compared with Leucaena leucocephala, the seed germination rate, root biomass, root-shoot ratio and plant N:P ratio of Albizia kalkora were significantly increased by 58.82%, 76.13%, 90.59% and 18.42%, respectively(P<0.05).(2)Under drought conditions, the root biomass and plant nitrogen content of Albizia kalkora were significantly lower than those under moist conditions by 33.67% and 8.65%(P<0.05), and the plant height, aboveground biomass and root biomass of Leucaena leucocephala under drought conditions were 39.32%, 40.06% and 39.61% lower than those under moist conditions(P<0.05), indicating that drought inhibited the growth and nutrient uptake of both plants.(3)The quantity of root nodules in Albizia kalkora under drought conditions was higher than that under moist conditions(P<0.05), and the quantity of root nodules in Leucaena leucocephala under moist conditions was higher than that under drought conditions, but no significant difference.(4)Except for the litter proportion, soil microbial inoculation and the interaction between soil microorganisms and water had no significant effect on the growth of Albizia kalkora and Leucaena leucocephala. The above results suggest that Albizia kalkora is more suitable for drought environment than Leucaena leucocephala, which provides a theoretical basis for the selection of species for vegetation restoration in dry-hot valley, but the effects of soil microorganisms on plant growth are worthy of further exploration and research.