Land‐sparing agriculture sustains higher levels of avian functional diversity than land sharing

Abstract

The ecological impacts of meeting rising demands for food production can potentially be mitigated by two competing land‐use strategies: off‐setting natural habitats through intensification of existing farmland (land sparing), or elevating biodiversity within the agricultural matrix via the integration of “wildlife‐friendly” habitat features (land sharing). However, a key unanswered question is whether sparing or sharing farming would best conserve functional diversity, which can promote ecosystem stability and resilience to future land‐use change. Focusing on bird communities in tropical cloud forests of the Colombian Andes, we test the performance of each strategy in conserving functional diversity. We show that multiple components of avian functional diversity in farmland are positively related to the proximity and extent of natural forest. Using landscape and community simulations, we also show that land‐sparing agriculture conserves greater functional diversity and predicts higher abundance of species supplying key ecological functions than land sharing, with sharing becoming progressively inferior with increasing isolation from remnant forest. These results suggest low‐intensity agriculture is likely to conserve little functional diversity unless large blocks of adjacent natural habitat are protected, consistent with land sparing. To ensure the retention of functionally diverse ecosystems, we urgently need to implement mechanisms for increasing farmland productivity whilst protecting spared land.

The worldwide impact of urbanisation on avian functional diversity

“…First, we used data from Pigot et al (2020) on eight morphological traits measured with callipers from museum specimens (Appendix ). The traits include beak length, depth and width (to describe major axes of variation in beak morphology, the primary resource related trait in birds), wing length and first secondary feather length (to describe variation in wing shape, related to flight strength and dispersal ability), tarsus length and tail length (related to microhabitat and foraging substrate) and body size (related to energetic constraints, competitive ability and pace of life)(Cannon et al 2019). In addition, we used the length of the wing and first secondary feather to estimate the hand‐wing index (Claramunt et al 2012).…”

Secondary tropical forests recover dung beetle functional diversity and trait composition

“…Therefore, in combination with understanding of how habitat change impacts the relative abundance of different functional traits (e.g. Edwards et al, 2013a;Cannon et al, 2019), FD is important in predicting the effects of future land-use management on ecosystem functioning. For example maintaining functionally diverse communities of ground beetles and bees is vital for pollination and natural pest control to safeguard future food production (Woodcock et al, 2013).…”

Envisioning the Future of Mosaic Landscapes: Actor Perceptions in a Mixed Cocoa/Oil-Palm Area in Ghana

“…The results show that farmers from the cocoa area prefer a more segregated landscape (land sparing), whereas oilpalm-side farmers prefer a more integrated landscape (land sharing). Farmers' preference for segregation in cocoa areas is motivated by crop damage caused by timber operators (Marfo and Schanz 2009;Ros-Tonen and Derkyi 2018), conflicts over unfarmed areas (Derkyi et al 2014), and prospects of greater efficiency and higher yields (income) (Phalan et al 2011;Cannon et al 2019). Contrastingly, farmers in the oil-palm area have experienced the negative consequences of a highly segregated landscape, despite the higher incomes that tree crops generate.…”