Article

Farming and the Fate of Wild Nature

Department of Zoology, University of Cambridge, Downing Street, Cambridge, CB2 3EJ, UK.
Science (Impact Factor: 33.61). 02/2005; 307(5709):550-5. DOI: 10.1126/science.1106049
Source: PubMed

ABSTRACT

World food demand is expected to more than double by 2050. Decisions about how to meet this challenge will have profound effects on wild species and habitats. We show that farming is already the greatest extinction threat to birds (the best known taxon), and its adverse impacts look set to increase, especially in developing countries. Two competing solutions have been proposed: wildlife-friendly farming (which boosts densities of wild populations on farmland but may decrease agricultural yields) and land sparing (which minimizes demand for farmland by increasing yield). We present a model that identifies how to resolve the trade-off between these approaches. This shows that the best type of farming for species persistence depends on the demand for agricultural products and on how the population densities of different species on farmland change with agricultural yield. Empirical data on such density-yield functions are sparse, but evidence from a range of taxa in developing countries suggests that high-yield farming may allow more species to persist.

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    • "As land must be used to provide food for earth's continuously growing population, the success of biodiversity conservation is tightly linked to our ability to integrate conservation efforts into human-driven landscapes (Fahrig et al., 2011).Two main strategies known as land sparing and land sharing have been proposed to protect biodiversity (Phalan et al., 2011). Land sparing refers to the practice of intensifying agriculture on productive soils to gain areas for efficient species conservation in other places, whereas land sharing aims at integrating conservation and crop production on the same site (also described as wildlife-friendly farming;Green et al., 2005). Up to now, neither of these strategies seems appropriate to achieve all conservation goals and for all land-use systems (Grau et al., 2013). "
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    • "Biodiversity conservation is increasingly recognized as a crucial task for sustaining several ecosystem services that improve human wellbeing (Cardinale et al., 2012). Agriculture is among the main causes of biodiversity loss worldwide (Frishkoff et al., 2014; Karp et al., 2012; Pignatti, 1982) and there is increasing awareness that future biodiversity conservation will largely depend on the capability of cultivated areas to provide suitable habitats for species and communities of conservation concern (Baudron and Giller, 2014; Green et al., 2005; Phalan et al., 2011; Wright et al., 2012). "
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    • "Two divergent strategies to optimize commodity production and biodiversity conservation in the face of land scarcity have emerged: the land sparing and land sharing strategies (Fischer et al., 2014). With land sparing, agricultural areas are managed intensively, creating the maximum agricultural yield from a minimal area, so that other areas can be " spared for nature " (Green et al., 2005). Land sharing, however, encourages biodiversity within each farm (Fischer et al., 2008), whether by including areas that are structurally similar to native vegetation or having high levels of heterogeneity within the farmed area or along the margins. "
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