title: Tradeoffs between income, biodiversity, and ecosystem functioning during tropical rainforest conversion and agroforestry intensification.
abstract: Losses of biodiversity and ecosystem functioning due to rainforest destruction and agricultural intensification are prime concerns for science and society alike. Potentially, ecosystems show nonlinear responses to land-use intensification that would open management options with limited ecological losses but satisfying economic gains. However, multidisciplinary studies to quantify ecological losses and socioeconomic tradeoffs under different management options are rare. Here, we evaluate opposing land use strategies in cacao agroforestry in Sulawesi, Indonesia, by using data on species richness of nine plant and animal taxa, six related ecosystem functions, and on socioeconomic drivers of agroforestry expansion. Expansion of cacao cultivation by 230% in the last two decades was triggered not only by economic market mechanisms, but also by rarely considered cultural factors. Transformation from near-primary forest to agroforestry had little effect on overall species richness, but reduced plant biomass and carbon storage by approximately 75% and species richness of forest-using species by approximately 60%. In contrast, increased land use intensity in cacao agroforestry, coupled with a reduction in shade tree cover from 80% to 40%, caused only minor quantitative changes in biodiversity and maintained high levels of ecosystem functioning while doubling farmers' net income. However, unshaded systems further increased income by approximately 40%, implying that current economic incentives and cultural preferences for new intensification practices put shaded systems at risk. We conclude that low-shade agroforestry provides the best available compromise between economic forces and ecological needs. Certification schemes for shade-grown crops may provide a market-based mechanism to slow down current intensification trends.
authors.affiliation: Department of Agroecology, Georg-August-Universität Göttingen, Waldweg 26, 37073 Göttingen, Germany.
authors.forename: Ingolf
authors.initials: I
authors.lastname: Steffan-Dewenter
authors.forename: Michael
authors.initials: M
authors.lastname: Kessler
authors.forename: Jan
authors.initials: J
authors.lastname: Barkmann
authors.forename: Merijn M
authors.initials: MM
authors.lastname: Bos
authors.forename: Damayanti
authors.initials: D
authors.lastname: Buchori
authors.forename: Stefan
authors.initials: S
authors.lastname: Erasmi
authors.forename: Heiko
authors.initials: H
authors.lastname: Faust
authors.forename: Gerhard
authors.initials: G
authors.lastname: Gerold
authors.forename: Klaus
authors.initials: K
authors.lastname: Glenk
authors.forename: S Robbert
authors.initials: SR
authors.lastname: Gradstein
authors.forename: Edi
authors.initials: E
authors.lastname: Guhardja
authors.forename: Marieke
authors.initials: M
authors.lastname: Harteveld
authors.forename: Dietrich
authors.initials: D
authors.lastname: Hertel
authors.forename: Patrick
authors.initials: P
authors.lastname: Höhn
authors.forename: Martin
authors.initials: M
authors.lastname: Kappas
authors.forename: Stefan
authors.initials: S
authors.lastname: Köhler
authors.forename: Christoph
authors.initials: C
authors.lastname: Leuschner
authors.forename: Miet
authors.initials: M
authors.lastname: Maertens
authors.forename: Rainer
authors.initials: R
authors.lastname: Marggraf
authors.forename: Sonja
authors.initials: S
authors.lastname: Migge-Kleian
authors.forename: Johanis
authors.initials: J
authors.lastname: Mogea
authors.forename: Ramadhaniel
authors.initials: R
authors.lastname: Pitopang
authors.forename: Matthias
authors.initials: M
authors.lastname: Schaefer
authors.forename: Stefan
authors.initials: S
authors.lastname: Schwarze
authors.forename: Simone G
authors.initials: SG
authors.lastname: Sporn
authors.forename: Andrea
authors.initials: A
authors.lastname: Steingrebe
authors.forename: Sri S
authors.initials: SS
authors.lastname: Tjitrosoedirdjo
authors.forename: Soekisman
authors.initials: S
authors.lastname: Tjitrosoemito
authors.forename: André
authors.initials: A
authors.lastname: Twele
authors.forename: Robert
authors.initials: R
authors.lastname: Weber
authors.forename: Lars
authors.initials: L
authors.lastname: Woltmann
authors.forename: Manfred
authors.initials: M
authors.lastname: Zeller
authors.forename: Teja
authors.initials: T
authors.lastname: Tscharntke
mesh_terms: D000383:Agriculture; D000818:Animals; D044822:Biodiversity; D002099:Cacao; D016468:Forestry; D007182:Income; D007313:Insecta; D018515:Plant Leaves / Q000502:physiology; D013045:Species Specificity; D014197:Trees / Q000502:physiology*; D014329:Tropical Climate