The particular structure-function relationships of dryland landscapes are rarely considered in the design of dryland restoration actions. Promoting the establishment of species-diverse plant patches that enhance resource conservation could contribute to restoration success and biodiversity conservation in drylands. Using experimental plantations on bare slopes, we investigated the effect of increasing plant density and/or diversity within the plant patch on the productivity, resource conservation, and restoration potential of the target area. On 56 experimental plots, we created replicated patchy plant communities that varied in the number of both individuals and species per patch (1, 2, 4 and 8) and, for certain patch sizes, only in the number of species. For the first three years after planting, we found that increasing plant diversity and density, and thus patch size, reduced individual plant growth due to increasing competition within the patch. However, the individual biomass reductions did not compromise a positive net increase in total patch biomass with increasing patch size and diversity, which suggests some degree of functional complementarity within the patch. For equal patch size, increasing diversity either enhanced or did not affect individual plant growth, depending on the plant functional group considered. In general, larger and more diverse vegetation patches benefited from a higher sink capacity for rainfall and runoff water and a higher capacity for trapping sediments. Our results demonstrate that patch diversity and size control the recovery of drylands and highlight the potential of establishing functionally-diverse plant patches as a cost-effective approach for dryland restoration.
Audio/Video, Conference Presentation, SER2019
Pre-approved for CECs under SER's CERP program
Society for Ecological Restoration