Assessing the effectiveness of riparian buffers in protecting biodiversity

Riparian buffers – vegetation strips retained or established along waterways – are mandated in many countries for water and soil protection, yet their role in biodiversity conservation remains unclear. Our global meta-analysis compares forested riparian buffers (FRBs) with converted riparian zones (CRZs) in human-modified landscapes across forest biomes. We find that FRBs support higher animal biodiversity than CRZs at both local and landscape scales, particularly in agricultural areas. This pattern is consistent across most freshwater and riparian taxa, in both tropical and temperate regions. FRBs also harbor, on average, 32% more reference species (i.e., species found in continuous riparian forests) than do CRZs. Optimum buffer width estimates for species conservation were roughly an order of magnitude wider for birds and mammals (~ 200–380 m on each river side), than for amphibians (20–50 m) and invertebrates (6–50 m). Our findings support FRBs as an important global strategy for conserving biodiversity.