Closing yield gaps: perils and possibilities for biodiversity conservation

Abstract

Increasing agricultural productivity to ‘close yield gaps’ creates both perils and possibilities for biodiversity conservation. Yield increases often have negative impacts on species within farmland, but at the same time could potentially make it more feasible to minimize further cropland expansion into natural habitats. We combine global data on yield gaps, projected future production of maize, rice and wheat, the distributions of birds and their estimated sensitivity to changes in crop yields to map where it might be most beneficial for bird conservation to close yield gaps as part of a land-sparing strategy, and where doing so might be most damaging. Closing yield gaps to attainable levels to meet projected demand in 2050 could potentially help spare an area equivalent to that of the Indian subcontinent. Increasing yields this much on existing farmland would inevitably reduce its biodiversity, and therefore we advocate efforts both to constrain further increases in global food demand, and to identify the least harmful ways of increasing yields. The land-sparing potential of closing yield gaps will not be realized without specific mechanisms to link yield increases to habitat protection (and restoration), and therefore we suggest that conservationists, farmers, crop scientists and policy-makers collaborate to explore promising mechanisms.

Trading carbon, biodiversity, and livelihoods: a landscape scale analysis of ecosystems services and trade-offs in land-use policy

“…While some identify land sparing as principally concerning land allocation, specifically setting aside land exclusively for conservation, without necessarily modifying yield Lindenmayer and Cunningham, 2013), the more generally accepted model implies some intensification of agriculture Phalan et al, 2011;. Intensification is often assumed to occur via actions that may negatively impact on biodiversity and other non-market societal values (Phalan et al, 2014), for example through creation of simplified habitats (e.g. monocultures; , irrigation, and increases in fertilizer and pesticide application , and other negative off-site environmental and social impacts (Castella et al, 2013;.…”

“…Increasing global population and changing consumption patterns, particularly toward animal protein and commodities such as soy and palm-oil, have led to suggestions that food production may need to double by 2050 (Tilman et al, 2001;Phalan et al, 2014). This increases pressure for intensification and expansion of agricultural land use and management (Stavins et al, 2003;Pirard and Belna, 2012;Laurance et al, 2014), which is cumulatively reducing the viability of natural ecosystems and their ability to support biological diversity and ecosystem services (Strobl et al, 2008;Laurance et al, 2014;Phalan et al, 2014;Renwick et al, 2014).…”

“…This increases pressure for intensification and expansion of agricultural land use and management (Stavins et al, 2003;Pirard and Belna, 2012;Laurance et al, 2014), which is cumulatively reducing the viability of natural ecosystems and their ability to support biological diversity and ecosystem services (Strobl et al, 2008;Laurance et al, 2014;Phalan et al, 2014;Renwick et al, 2014). Managing the underlying production-biodiversity trade-off is becoming an increasingly complex issue in both developing and advanced economies where sustaining or developing the economics, culture, and ecology of agricultural landscapes ranks high among both social and political priorities (Hamblin, 2009;Bekessy et al, 2010).…”

“…Both strategies can be effective given appropriate contexts (Martinet and Barraquand, 2012;Phalan et al, 2014), and decision makers need to determine which strategy is preferable in specific applications, or if alternative approaches, such as better land use planning from the outset, demand management, or addressing inefficiencies in food processing, distribution, and consumption, may better achieve their land-use objectives.…”

“…Sparing hinges on land allocation, specifically setting aside land primarily for biodiversity conservation Lindenmayer and Cunningham, 2013), coupled with intensification of agriculture in remaining production areas . Agricultural intensification is often assumed to occur via actions that may negatively impact on biodiversity and other non-market environmental and societal values (Phalan et al, 2014). For example, this can occur through reduced or altered habitat diversity (e.g.…”