Abstract
The desertification paradigm has a long history in the Sahel, from colonial to modern times. Despite scientific challenge, it continued to be influential after independence, revived by the dramatic droughts of the 1970s and 1980s, and was institutionalized at local, national and international levels. Collaborative efforts were made to improve scientific knowledge on the functioning, environmental impact and monitoring of selected agricultural systems over the long term, and to assess trends in the ecosystems, beyond their short term variability. Two case studies are developed here: the pastoral system of the arid to semi-arid Gourma in Mali, and the mixed farming system of the semi-arid Fakara in Niger. The pastoral landscapes are resilient to droughts, except on shallow soils, and to grazing, following a non-equilibrium model. The impact of cropping on the landscape is larger and longer lasting. It also induces locally high grazing pressure that pushes rangeland resilience to its limits. By spatial transfer of organic matter and mineral, farmers’ livestock create patches of higher fertility that locally enhance the system’s resilience. The agro-pastoral ecosystem remains non-equilibrial provided that inputs do not increase stocking rates disproportionately. Remote sensing confirms the overall re-greening of the Sahel after the drought of the 1980s, contrary to the paradigm of desertification. Ways forward are proposed to adapt the pastoral and mixed farming economies and their regional integration to the context of human and livestock population growth and expanding croplands.
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- 1.
In collaboration with IER (Mali Institute for Rural Economy) ILCA (International Livestock Centre for Africa, Addis Ababa, Ethiopia) first launched a multi-disciplinary assessment of the short term impact of the 1982-83 drought on pastoral systems in the Gourma region, then funded a ten years monitoring of the sites to assess the drought impact over the longer term. After 5 years with few observations, the site monitoring was resumed in 1999 under the African Monsoon Multi-disciplinary Analysis, AMMA project till 2009 (Redelsperger et al. 2006), it continued then under the AMMA-CATCH observatory (Mougin et al. 2009) but was scaled down since 2011 because of civil insecurity. From 2009 on, the monitoring also benefited from the research context provided by a series of ANR (French Research National Agency) funded research project: ECliS (‘Livestock Climate and Society’ between 2009 and 2012; http://eclis.get.obs-mip.fr/), ESCAPE (‘Environmental and social changes in Africa: past, present and future’ from 2012 onwards; http://www.locean-ipsl.upmc.fr/~ESCAPE/) and CAVIARS (‘Climate, agriculture and vegetation: impacts on aeolian erosion in the Sahel’ from 2013 onwards).
- 2.
In collaboration with INRAN (Niger National Institute for Agronomy Research), ILRI (International Livestock Research Institute, Nairobi, Kenya) started in June 1994 a multi-disciplinary diagnostic of mix crop-livestock production systems in Southern Sahel. The seasonal monitoring of 54 field sites was part of the farming system study and continued under different ILRI research projects till 2006. After two years’ interruption the site monitoring was resumed under the ECLiS (http://eclis.get.obs-mip.fr/) project and the AMMA-CATCH observatory. The Dantiandou district provided one of three sites retained by the international research project on the West African monsoon, AMMA (Cappelaere et al. 2009). In the meantime, ICRISAT (International Crops Research Institute for the Semi-Arid-Tropics, Hyderabad, India) developed in Dantiandou, in collaboration with INRAN and the University of Louvain-la-Neuve (Belgium), experimental research on options to intensify millet crop (fertilizer micro-dose, selected breeds of millet and cowpea, animal traction) as well as surveys on societal and economic issues (Saqali et al. 2010).
- 3.
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Acknowledgements
The authors are indebted to many colleagues and collaborators for the data collected and analysed over several decades both in Mali and Niger under a series of research projects and funding agencies listed in the endnotes. Among them they would particularly like to thank the main actors of the long term monitoring and production system studies: late Mohamed Idrissa Cissé, late Lassine Diarra, Youssouf Maiga and Nogmana Soumaguel in Mali, Adamou Kalilou, Oumar Moumouni and Seybou Garba in Niger. Among the colleagues whose works were particularly useful in this chapter, the authors would like acknowledge the works of Matthew Turner from University of Wisconsin, Augustine A. Ayantunde from ILRI, Manuela Grippa from the GET laboratory in Toulouse, Valérie Trichon from the University Paul Sabatier in Toulouse. The remote-sensing analyses are borrowed from Cécile Dardel PhD thesis and Mamadou Diawara contributed to the results on the livestock impact. The authors are grateful to Layne Coppock for his thorough review and to Mike Mortimore who has kindly edited the text in proper English. This publication was made possible through the support provided by the research project ‘Environmental and social changes in Africa: past, present and future (ESCAPE, ANR-10-CEPL-005) funded by ANR (French National Research Agency).
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Hiernaux, P., Dardel, C., Kergoat, L., Mougin, E. (2016). Desertification, Adaptation and Resilience in the Sahel: Lessons from Long Term Monitoring of Agro-ecosystems. In: Behnke, R., Mortimore, M. (eds) The End of Desertification? . Springer Earth System Sciences. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-642-16014-1_6
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