How does biodiversity affect ecosystem resilience?

Biodiversity underpins the capacity of ecosystems to absorb disturbance, reorganize, and continue providing essential functions. Decades of ecological research link species richness and functional diversity to greater stability in productivity, nutrient cycling, and resistance to pests and extreme events. David Tilman at the University of Minnesota demonstrated in long-term grassland experiments that plots with more plant species showed more stable biomass production through variable seasons and droughts, illustrating a natural insurance effect. Shahid Naeem at Columbia University further documented that diverse communities buffer population fluctuations because different species respond differently to environmental change.

Mechanisms linking biodiversity and resilience

Multiple, complementary mechanisms explain why biodiversity enhances resilience. Functional redundancy means that if one species declines, others with similar roles can maintain key processes. Response diversity, a concept articulated by Joe Cardinale at the University of Michigan, emphasizes that species performing the same function may react differently to stressors, spreading risk across the community. Complementarity in resource use and trophic interactions increases overall ecosystem productivity and recovery speed after disturbance. These mechanisms operate across scales: microbial diversity in soils affects nutrient availability for plants, while predator diversity can suppress outbreaks of herbivores that would otherwise shift community composition.

Causes of biodiversity loss that weaken resilience include habitat conversion, invasive species, pollution, overexploitation, and climate change. The Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services with inputs from many scientists including Robert Watson at the University of East Anglia identifies these drivers as interacting and accelerating global declines. When diversity erodes, systems lose both redundancy and the range of responses needed to cope with new stresses, making regime shifts and collapses more likely.

Consequences for people and places

Loss of resilience has direct consequences for human societies. Reduced pollinator diversity impairs crop yields and food security in agricultural regions; declines in wetland plant and invertebrate diversity worsen flood regulation for coastal communities. Terry Hughes at James Cook University documented how coral reef biodiversity influences recovery from mass bleaching events, affecting fisheries and tourism in island nations where livelihoods and culture are tightly bound to reef health. Cultural practices and territorial stewardship can either mitigate or exacerbate these trends. Fikret Berkes at the University of Manitoba has shown that Indigenous knowledge and locally adapted management often maintain diverse, resilient landscapes through practices that recognize long-term ecological variability.

Environmental and policy responses that prioritize biodiversity — protecting habitats, restoring native species assemblages, and maintaining landscape connectivity — strengthen resilience across ecosystems and human systems. Recognizing the multiple pathways by which species diversity buffers change helps managers design interventions tailored to local cultural and territorial contexts, whether in tropical forests, agricultural mosaics, or coral seascapes. The science makes clear that sustaining biodiversity is not an abstract conservation goal but a practical strategy to keep ecosystems functioning for present and future generations.