Species Composition and Diversity in Communities of Different Combating Rock Desertification Models
[Objective]The objective of this study was to understand the restoration pattern and process of species composition and diversity in communities of different combating rock desertification models.[Methods]An afforestation experiment with two tree species (Acrocarpus fraxinifolius and Dalbergia odorifera) and three combating rock desertification models (pure A.fraxinifolius plantations,pure D.odorifera plantations and mixed A.fraxinifolius×D.odorifera plantations) was conducted and the plant communities in these combating models were investigated to reveal the dynamics of species composition,importance value and diversity in different control models.[Results]After 4 years restoration,significant changes existed in plant species composition,especially the dominant and co-dominant species,of shrub and herbaceous layers in different combating models.The numbers of several invasive plants,such as Biden spilosa,Conyza canadensis,Oxalis corniculata,Eupatorium odoratum,Achyranthes aspera,Ageratum conyzoides,increased.The importance value of Biden spilosa(10.35~36.32) was 2.33~8.18 times of that in the shrub (4.44).Compared with the shrub,there was no significant difference in species richness in the three combating models.While significant difference existed in plant species diversity and evenness index.[Conclusion]The control effects of the two legume tree species and three models were similar.The mixed planting model had superior effects on plant species diversity and evenness index than the other models.Afforestation at abandoned farmland and shrub in karst area could accelerate vegetation restoration and reconstruction,significantly change the species composition and community structure in short term,but also emerge plant invasion rick to some extent.
rock desertificationafforestationAcrocarpus fraxinifoliusDalbergia odoriferapure plantationsmixed plantationsspecies diversity