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Tropentag, September 19 - 21, 2012 in Göttingen
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The Need for Eco-Efficient Landscapes to Prevent Irreversible Degradation of Agroecosystems in Deforested Amazonia
Patrick Lavelle1,9, Sylvain Doledec2, Valery Gond3, Johan Oszwald4, Iran Veiga5, Bertha Ramirez6, W. Santos5, X. Arnauld de Sartre7, Thibaud Decaens8, Michel Grimaldi9, B. Hubert10, M. Martins11, P. Lena9, P. de Robert9, A. Feijoo12, M.P. Hurtado9, G. Rodriguez6, D. Mitja9, I. Miranda13, E. Gordillo6, E. Velasquez14, T. Otero14, A. Velasquez6, J.M. Thiollay9, S. de Sousa5, L.E. Moreno6, George Brown15, R. Marichal16,9, P. Chacon17, C. Sanabria17, T. Desjardins9, T. Santana Lima13, F. Michelotti5, O. Villanueva6, Jaime Velasquez6, E. Guevarra1, Steve Fonte1
1International Center for Agricultural Resarch (CIAT), TSBF Institute, Colombia
2Lyon 1 University, France
3CIRAD, France
4Rennes 2 University, Geography, France
5Federal University of Para, NEAF, Brazil
6Universidad de la Amazonia, Florencia, Colombia
7Pau University, Geography, France
8Rouen University, Ecology, France
9Institut de Recherche pour le Développement (IRD), France
10Institut National de la Recherche Agronomique, France
11Museu Paraense Emílio Goeldi, Brazil
12Universidad Tecnológiga de Pereira, Faculdad de Ciencias Ambientales, Colombia
13Universidade Federal Rural da Amazônia, Brazil
14Universidad Nacional de Colombia, Colombia
15EMBRAPA Forestry, CNPF, Brazil
16Université Pierre et Marie Curie, France
17Universidad del Valle, Colombia
Abstract
Considerable effort has been devoted to the conservation of primary forest in the Amazon, but less so to design and implement ecoefficient uses of cleared land for meeting the economic, social and environmental challenges faced in the region. We conducted a multidisciplinary diagnostic of ecoefficiency in 51 farms from six regions of the Brazilian and Colombian Amazon cleared between 15 to 60 years ago, with diverse colonisation histories. Land-use intensity was assessed with an indicator based on present landscape composition and structure and the historical land-use change. Indicators of soil ecosystem services (ES: chemical fertility, hydric functions and C storage) and biodiversity of plants and 5 soil and above ground invertebrate groups were assessed. Intensity of land-use increased with time elapsed since deforestation along with production efficiency (farm incomes per ha and per labour unit) and social wellbeing. Meanwhile, an indicator of biodiversity continued unchanged as land-use intensity increased until a well-marked tipping point, beyond which biodiversity fell sharply. A composite indicator of soil ES decreased regularly with land-use intensity. An ecoefficiency index, that combines indicators of social wellbeing, productivity, biodiversity and ES, also exhibited a sudden decrease when land-use intensity exceeded a critical threshold value. This tipping point corresponds with a shift from predominantly forested to open agropastoral landscapes, when the last forest patches become fragmented before disappearing. At that point, only 20% of the original primary forest is left on average. Landscapes dominated by agroforestry production systems had much higher ecoefficiency, with a higher productivity than extensive livestock breeding systems and greater conservation of biodiversity and ES. Our study indicates the need for reconstructing landscapes in deforested Amazonia, by identifying the best spatial combination of productive systems that sustain livelihoods and natural ecosystems that act as buffers to prevent degradation of ES and biodiversity.
Keywords: Amazonia, biodiversity, ecoefficiency, ecosystem services, land use intensity, landscape, tipping point
Contact Address: Patrick Lavelle, International Center for Agricultural Resarch (CIAT), TSBF Institute, Cali, Colombia, e-mail: p.lavelle
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