Agroforestry and Biodiversity

Declining biodiversity (BD) is affecting food security, agricultural sustainability, and environmental quality. Agroforestry (AF) is recognized as a possible partial solution for BD conservation and improvement. This manuscript uses published peer-reviewed manuscripts, reviews, meta-analysis, and federal and state agency documents to evaluate relationships between AF and BD and how AF can be used to conserve BD. The review revealed that floral, faunal, and soil microbial diversity were significantly greater in AF as compared to monocropping, adjacent crop lands, and within crop alleys and some forests. Among the soil organisms, arbuscular mycorrhizae fungi (AMF), bacteria, and enzyme activities were significantly greater in AF than crop and livestock practices. Agroforestry also creates spatially concentrated high-density BD near trees due to favorable soil-plant-water-microclimate conditions. The greater BD was attributed to heterogeneous vegetation, organic carbon, microclimate, soil conditions, and spatial distribution of trees. Differences in BD between AF and other management types diminished with time. Evenly distributed leaves, litter, roots, dead/live biological material, and microclimate improve soil and microclimate in adjacent crop and pasture areas as the system matures. Results of the study prove that integration of AF can improve BD in agricultural lands. Selection of site suitable tree/shrub/grass-crop combinations can be used to help address soil nutrient deficiencies or environmental conditions. Future studies with standardized management protocols may be needed for all regions to further strengthen these findings and to develop AF establishment criteria for BD conservation and agricultural sustainability.