Biodiversity

Biodiversity is not simply the number of species present. It is the variety and interaction that make ecosystems work.

Biodiversity is often reduced to a count of visible species: birds in a forest, insects on a farm or trees in a landscape. Species richness matters, but it is only one part of the concept. The Convention on Biological Diversity defines biological diversity as variability among living organisms from all sources, including diversity within species, between species and of ecosystems.

Those three levels - genetic, species and ecosystem diversity - are inseparable from the relationships that connect them.

Genetic diversity is the variation within a species. In agriculture it can determine whether crops have the traits needed to tolerate heat, resist disease or adapt to changing rainfall. When production becomes dependent on a narrow genetic base, efficiency may increase in the short term while vulnerability grows. Conserving diverse varieties and wild relatives is therefore not nostalgia.

It is a practical source of future options.

Species diversity describes the variety of plants, animals, fungi and microorganisms within a place. Different species perform different functions. Pollinators support reproduction. Predators help regulate pests. Fungi and soil organisms decompose organic matter and cycle nutrients. Trees provide shade, habitat and structural complexity.

Losing a species can matter not only because something unique disappears, but because the interactions supporting the wider system become weaker.

Ecosystem diversity concerns the mosaic of forests, wetlands, grasslands, rivers, farms and other habitats across a landscape. These systems exchange water, nutrients, organisms and energy. A river does not stop at a farm boundary. Pollinators move between crops and natural vegetation. Birds and mammals depend on connected habitat rather than isolated fragments.

Biodiversity must therefore be considered across landscapes as well as within individual production sites.

Agriculture depends on this living infrastructure. Soil fertility, pollination, water regulation, pest control and climate moderation are all influenced by biological diversity. Yet agriculture is also a major force shaping it.

Habitat conversion, pollution, invasive species, overuse of inputs and simplified production systems can reduce both the amount of biodiversity present and the ability of ecosystems to function.

Coffee illustrates the difference between greenness and biodiversity. A farm with many trees may look nature-friendly, but a canopy composed of one introduced species can provide less habitat and fewer ecological functions than a diverse mix of native or locally appropriate trees.

Likewise, a high number of species does not automatically mean the ecosystem is healthy if sensitive species have disappeared, populations are collapsing or habitat is fragmented.

Research in coffee landscapes shows why these relationships matter economically as well as ecologically. In southern Costa Rica, Karp and colleagues found that forest elements around coffee farms supported insect-eating birds, strengthened control of the coffee berry borer and were associated with higher coffee yield. The point was not that one bird species 'delivered' sustainability.

It was that habitat, species and farm performance were connected through an ecological function that a simple tree count would miss.

This is why biodiversity measurement is difficult. Species counts are useful, but they may need to be combined with abundance, habitat condition, connectivity, ecological integrity and functional diversity. The correct measure depends on the decision being made. A programme focused on pollination needs different evidence from one focused on watershed protection or threatened species.

Scale matters as much as the indicator. A farm may improve habitat while the surrounding landscape continues to degrade. A company may protect one sourcing area while shifting pressure elsewhere. Biodiversity claims should therefore specify the geographic boundary, the baseline, the taxa or ecosystem functions considered and the timeframe over which change is expected.

Biodiversity also has a strong human dimension. Indigenous Peoples and local communities often manage landscapes containing high biological and cultural diversity. Conservation that ignores rights, knowledge, access and livelihoods can create harm even when ecological objectives are well intentioned.

Protecting biodiversity effectively requires participation, fair governance and respect for the people whose decisions shape the landscape every day.

The language used by organisations should distinguish activities from outcomes. Planting trees, creating buffer zones or training farmers may support biodiversity, but they do not prove that biodiversity has improved. The claim becomes credible only when evidence shows better habitat, stronger populations, improved connectivity or restored ecological function.

Practical application

A biodiversity strategy for a coffee landscape might begin by identifying remaining natural habitat, riparian areas, movement corridors, important species and the ecological functions most relevant to production. Farm actions could include retaining diverse shade, reducing pesticide risks, protecting waterways and increasing habitat continuity.

Landscape actions may involve coordinating across farms, communities and public land.

Monitoring should be proportionate to the claim. Remote sensing can describe land cover and fragmentation; field surveys can assess species, abundance and habitat quality; farmer and community knowledge can reveal seasonal change and local priorities. No single dataset captures biodiversity completely, so evidence is strongest when methods are combined and limitations are stated.

Why it matters

Biodiversity supports the ecological processes that make agriculture and human wellbeing possible. It also provides options for adaptation when conditions change. Protecting biodiversity is therefore not an optional conservation activity added to production. It is part of maintaining the living systems on which production depends.

Common misconception

Biodiversity is often understood as protecting rare wildlife in protected areas. It includes those species, but it also includes genetic variation, common species, microorganisms, agricultural diversity and the ecosystems connecting working landscapes. A place can contain many species and still be ecologically degraded if abundance, integrity or connectivity are declining.

Connections

Regenerative agriculture seeks to rebuild ecological function, and biodiversity is both a component and an indicator of that recovery. Ecosystem restoration addresses places where condition or function has already been lost. Climate resilience depends on diversity because systems with more varied species, genes, habitats and livelihood options often have more ways to respond to disturbance.

A question worth asking

When your organisation reports that it has supported biodiversity, is it describing an activity, a change in habitat, a change in species or a demonstrable improvement in ecological function - and does the evidence match the claim?

Selected references

- Convention on Biological Diversity. 1992. Article 2: Use of Terms.

- IPBES. 2019. Global Assessment Report on Biodiversity and Ecosystem Services.

- Karp, D. S. et al. 2013. Forest Bolsters Bird Abundance, Pest Control and Coffee Yield. Ecology Letters 16: 1339-1347.

- Philpott, S. M. et al. 2008. Biodiversity Loss in Latin American Coffee Landscapes: Review of the Evidence on Ants, Birds and Trees. Conservation Biology 22(5): 1093-1105.

- Tscharntke, T. et al. 2012. Landscape Moderation of Biodiversity Patterns and Processes - Eight Hypotheses. Biological Reviews 87: 661-685.