The status of plant diversity in different land use types of agricultural landscape of west Oromia, Ethiopia

Abstract

Understanding how land use types embedded in agricultural landscapes support forest biodiversity is critical, especially during this period of continuing fragmentation and habitat losses in natural ecosystems. Here, we explored the floristic species composition with respect to land use types in the agroecosystem of west Oromia, Ethiopia. For this, a systematic sampling method was employed to collect floristic data from 122 main quadrats and 610 sub-quadrats, following transects laid out with a 1500-m interval. The main quadrats were arranged on transects with an 800-m interval to assess woody species, and five sub-quadrats (i.e., four at the corners and one at the center) were taken within each main plot to assess herbaceous plants. Accordingly, the floristics were assessed with respect to the identified five land use types, including crop land, forest, grazing land, home gardens, and riverine. We used a one-way ANOVA to test the difference in species diversity among the land use types. Adonis 2 and indval functions were used to describe the species composition and indicator species in relation to the land use types. Moreover, NMDS was applied to visualize the associations of the species composition with environmental variables in ordination space. A total of 285 plant species belonging to 220 genera and 89 families were recorded. Our results showed significant differences in species diversity, dissimilarity in species composition, and species indicator values among the land use types. These results indicate that the potentiality of the land use types in supporting plant diversity is significantly different; for example, species diversity and abundances were higher in grazing lands and home gardens when compared with other land use types. Overall, our findings suggest that conservation strategies in agricultural landscapes should take into account the differences in capacity for supporting biodiversity among land use types when planning.

Keywords

• Dry afromontane
• Degradation
• Matrix land
• Refugia
• Species richness
• Vegetation