How to Bend the Curve of Biodiversity Loss?

A long-term debate framed in five acts

Damien Beillouin (UR Hortsys) et Bruno Rapidel

Context: A Scientific Consensus

  • Biodiversity as a Planetary Boundary
    • The biosphere integrity is transgressed globally, threatening ecosystem functioning and resilience (Steffen et al., 2015; Rockström et al., 2009).
    • Loss of species and functional diversity compromises ecosystem services critical to human well-being.
    • Biodiversity decline is systemic and multi-scalar, not confined to specific regions or taxa.
  • Agriculture as the Dominant Driver
    • Land-use change, habitat fragmentation, monocultures, and intensification are primary pressures.
    • Global syntheses identify agriculture as the principal driver of terrestrial biodiversity loss (IPBES, 2019; FAO, 2022).

Act I — Land Sparing vs. Land Sharing

  • Context
    • University of Cambridge initiated key debates on land use and biodiversity.
    • Land Sparing: Increase production on smaller areas, protect the rest.
    • Land Sharing: Integrate conservation and production across landscapes.
  • Key Studies
    • Green et al., Science 2005: Model suggests land sparing is more effective.

Act II — Early Scientific Debates

  • Phalan et al., Science 2011 (model-based insights) Most trade-offs concave → sparing preferable.

  • Fisher et al.(2014), Conservation Letters (practical limitations and critiques)

    • Many countries cannot implement sparing.
    • Some areas allow production without biodiversity loss.
    • Not all regions suit intensive agriculture.
    • Sparing is complex socially and ecologically.

ACT III. Land Sparing vs Sharing: Integrated Insights

Empirical Evidence
- Sparing & sharing overlap; consider continuum approach (Sidemo-Holm, 2021)
- No universal solution; local context matters (Augustiny, 2025)
- Sparing & sharing can be complementary, not exclusive (Valente, 2022)

ACT III. Land Sparing vs Sharing: Integrated Insights

Conceptual Reframing
- Sparing vs sharing: too simplistic (Kremen, 2015)
- Combine protected areas + biodiversity-friendly farming
- Agroecology & landscape heterogeneity sustain biodiversity
- Food production coexists with conservation
- Solutions are context-specific

Practical Implications
- Limits to sparing: socio-economic, governance, ecological constraints (Fisher, 2014)
- Participatory planning is essential (Loconto, 2020)
- Stakeholder perspectives are critical for adoption (Baudron, 2021)

Act IV — Scientific Dialogue Across Three Stages

Author Key Message
Balmford et al. (Jan 2025) High-yield farming crucial to reduce land demand and limit biodiversity loss
Beillouin et al. (Aug 2025) Exclusive yield focus dangerous; must integrate social, ecological, and economic dimensions
Balmford et al. (Aug 2025) Pragmatic yield focus; maintain yields while enabling biodiversity-friendly practices

Rethinking Agricultural Productivity Beyond Yields

Author Productivity Focus Key Points
Balmford et al. (Jan 2025)

Downstream solutions (diet, waste reduction) insufficient

High-yield agriculture is essential to reduce land demand and limit biodiversity loss

“sustained access to fertilizer, improved varieties [including genetically modified], markets and sound agronomic advice”

“Jevons effects are rare”

Yield focused.

Relies on fertilizers, improved varieties (including GMOs), market access, and agronomic guidance.


-> cherry picking of the evidence?
Beillouin et al. (Aug 2025)

“Decades of yield-centric agriculture, divorced from ecological and social concerns, have proven inadequate”

Singular focus on yield ignores environmental and social externalities

“the hidden costs of food systems, estimated at $10 trillion in purchasing power parity in 2020”

“highlights potential rebound/Jeavons effects and spatial displacement”

 Risks biodiversity decline, inequity, malnutrition, and ecosystem degradation
Balmford et al. (Aug 2025)

Pragmatic yield focus: maintain productivity where necessary

“do not advocate a continuation of business-as-usual high-yield farming.”

“farming practices need to be evaluated based on their environmental outcomes and their impacts”

“Jevons effects—appear to be rare in agriculture”

Combines yield maintenance with biodiversity-friendly practices and context-specific strategies

Most actions that make farmland more accommodating for biodiversity reduce yields.

On-Farm Biodiversity Conservation for Global Targets

Author Biodiversity Key Points
Balmford et al. (Jan 2025) Land sparing protects species; assumed effective protection reduces land conversion Focus on spatial protection; frames conservation as a trade-off against yields.
Beillouin et al. (Aug 2025)

Sparing effectiveness is overestimated

“Effective ‘spared’ land protection necessitates more than spatial designation”

A risk for agrobiodiversity loss?

“GBF targets 4 and 10 highlight the need to include agrobiodiversity”

 Incomplete protection, and agrobiodiversity loss; advocates landscape-scale, multifunctional management aligned with GBF targets
Balmford et al. (Aug 2025) Agrobiodiversity can be maintained within productive landscapes weak support for hybrid strategies, questioning the quality of the scientific evidence

Socially Just Approaches to Agricultural Transitions

Author Social & Economic Key Points
Balmford et al. (Jan 2025)

Land sparing framed as a conservation tool

Downstream solutions (diet, waste reduction) insufficient

 Treats social equity as secondary; frames conservation through a top-down, yield-centric lens with limited attention to farmer autonomy or local contexts.
Beillouin et al. (Aug 2025)

Risks reinforcing corporate dominance and marginalizing smallholders

“Technology-based intensification is capital-intensive, which smallholders struggle to compete with, leading to displacement or economic dependence on large agribusinesses”

“multi-criteria determinants of adoption and maintenance of ecologically friendly practices”

 Agricultural transitions are socio-ecological processes; that shapes power dynamics and access to resources, and depends on social, institutional, and cultural factors, not just technical feasibility.
Balmford et al. (Aug 2025)

Supportive interventions can reduce inequities

“compelling econometric analysis confirms that growing Bt rather than conventional cotton boosts long-term yields, cuts pesticide use and increases smallholder welfare [35]—which is why almost 100% of growers continue to use Bt seeds (M Qaim, 2025, personal communication)”

 High-yield practices should be evaluated for equity and well-being; targeted, evidence-based interventions can support smallholder welfare while aligning productivity with social justice

ACT V. Evolution of the Land Sparing vs Sharing Debate

  1. Major Trends

From binary sparing vs sharing to context-dependent, integrative frameworks, Integration of biodiversity, social equity, and economic feasibility

Integration of spatial scales: Yield increases can reduce land conversion.

Shift toward evidence-based, site-specific recommendations, Recognition that effective conservation requires hybrid strategies + multi-level policy support

  1. Key Divergences in the Literature

Sparing vs Sharing: Idealized sparing vs multifunctional landscapes; trade-offs between simplicity and ecological realism

Socio-Economic Lens: Yield-efficiency vs equity; normative assumptions influence interpretation

Agrobiodiversity & Farm Practices: Productivity–diversification debate; scale, metrics, and socio-ecological framing drive divergence

Beyond Land Sparing vs Sharing: Scientific & Practical Bottlenecks

1. Conceptual & epistemic limitations
- Simplified yield-biodiversity models fail to capture multi-dimensional socio-ecological realities.
- Evidence is fragmented: site-specific, short-term, or taxonomically narrow.
- Weak integration of ecological theory, agronomy, and socio-economic contexts.


2. Scientific debates unresolved
- Trade-offs between yield, biodiversity, and social outcomes remain poorly quantified.
- Leakage, rebound effects, and global land-use consequences are incompletely understood.
- Lack of multi-criteria metrics integrating biodiversity, ecosystem services, and social equity.

Questions/remarks?

Details on — Sustainable High-Yield Farming: Key Findings (Balmford et al., 2025)

  • Downstream solutions are insufficient:
    • Dietary shifts and reducing food loss help, but consumer choices alone cannot solve biodiversity loss.
    • Limiting biodiversity impacts at the production stage is essential.
  • Evidence-based synthesis:
    • Comparative studies with standardized abundance measures across many species and yield ranges.
    • High-yield vs low-yield agricultural sites analyzed across multiple regions.
  • Biodiversity outcomes:
    • Majority of species favor land sparing.
    • Some species benefit from low-yield farmland.
    • Most threatened species clearly prefer land sparing.


  • Closing yield gaps:
    • Many regions (e.g., Brazil) still have yield gaps; high-yield systems must be environmentally sustainable.
    • Key options: improved varieties, integrated pest management, conservation agriculture, and precision farming.
    • Practices like organic, grass-fed livestock, or urban agriculture are generally less effective for sparing natural habitats.
  • Avoiding rebound effects:
    • Higher yields can unintentionally drive land expansion (Jevons effect). UE focused (?)
    • Requires policies linking yield gains to habitat protection to prevent further biodiversity loss.
  • Policy and management tools:
    • Spatial zoning and protection of sensitive/frontier areas.
    • Market instruments and direct incentives, though effectiveness varies.
    • Integrated, context-specific strategies balancing productivity, biodiversity, and social feasibility.
  • Collaboration and governance:
    • Achieving high-yield biodiversity-friendly farming depends on cooperation between farmers, conservationists, and policymakers.
    • Without such alignment, progress towards slowing biodiversity loss is unlikely.

Act XI — Beyond Yields: Key Critiques of Yield-Centric Approaches

  • Single-focus on yield is misleading:
    • Decades of high-yield strategies have failed to halt biodiversity loss.
    • Ignoring ecological and social dimensions leads to hidden environmental and social costs.
  • Biodiversity at farm scale:
    • Maintaining on-farm biodiversity is essential.
    • Systems like cover crops and agroforestry can provide multiple benefits simultaneously.
  • Land sparing limitations:
    • Land sparing not fully effective due to leakage effects (higher yields driving land conversion elsewhere).
    • Agrobiodiversity is threatened under land sparing strategies.


  • Complex social dynamics:
    • Farmers’ decision-making is multi-faceted; one-size-fits-all intensification is unrealistic.
    • Systems must consider justice, equity, and local knowledge.
  • Risks of intensification:
    • Can reinforce agribusiness dominance and biological appropriation (e.g., GMOs).
    • Policies must avoid marginalizing smallholders or promoting unsustainable practices.
  • Integrated solutions required:
    • Reconcile productivity with biodiversity through holistic, site-specific socio-ecological strategies.
    • Focus on system-level interventions, not only yield increases.