Abstract
In Ethiopia, human migration is known to be influenced by environmental change—and vice versa. Thus, degradation of environmental conditions can contribute to out-migration, and in-migration can cause environmental changes at the immigrants’ destination. The aim of our study was to systematically identify regions in which socio-ecological pressures can arise from high population densities, migration, land degradation, and/or rainfall variability. We combined population census data at the district level with high-resolution remote sensing data regarding rainfall variability, land degradation, and land cover. We identified districts in which high population density is coupled with both a steep decline in net primary production (NPP) and large precipitation variability. The affected regions are mainly cropping regions located in the northern highlands and in the central part of the Great Rift Valley. We consider these regions to be particularly prone to environmental changes; moreover, high population density places additional stress on local natural resources. Next, we identified districts in which high in-migration is coupled with both a strong decline in NPP and low rainfall variability, proposing that land degradation in these regions is likely to have resulted from human activity rather than climatic factors. The affected regions include parts of the Awash Valley, regions surrounding Lake Tana, and the mountainous regions between Addis Ababa, Bedele, and Jima. We found these hotspots of in-migration and land degradation are dominantly grasslands regions, which have been characterized by significant cropland expansion during the period studied. Whereas exploring causal relationships between migration, environmental change, and land cover change is beyond the scope of our study, we have pinpointed regions where these processes coincide. Our findings suggest that at the regional scale, deteriorating environmental conditions can be both the cause and the effect of migration.
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References
Abdi H, Seaquist J, Tenenbaum D, Eklundh L, Ardö J (2014) The supply and demand of net primary production in the Sahel. Environ Res Lett 9:094003–094011. doi:10.1088/1748-9326/9/9/094003
Adger WN, Huq S, Brown K, Conway D, Hulme M (2003) Adaptation to climate change in the developing world. Prog Dev Stud 3:179–195. doi:10.1191/1464993403ps060oa
Anseeuw W, Lay J, Messerli P, Giger M, Taylor M (2013) Creating a public tool to assess and promote transparency in global land deals: the experience of the Land Matrix. J Peasant Stud 40:521–530. doi:10.1080/03066150.2013.803071
Asfaw W, Tolossa D, Zeleke G (2010) Causes and impacts of seasonal migration on rural livelihoods: case studies from Amhara Region in Ethiopia. Nor Geogr Tidsskr 64:58–70. doi:10.1080/00291950903557696
Bai ZG, Dent DL, Olsson L, Schaepman ME (2008) Proxy global assessment of land degradation. Soil Use Manag 24:223–234. doi:10.1111/j.1475-2743.2008.00169.x
Bank TW (2008) World Development Report 2008. Agriculture for Development. In: Bank TW (ed) The World Bank, Washington, DC
Bantider A, Hurni H, Zeleke G (2011) Responses of rural households to the impacts of population and land-use changes along the Eastern Escarpment of Wello, Ethiopia. Nor Geogr Tidsskr 65:42–53. doi:10.1080/00291951.2010.549954
Bardsley D, Hugo G (2010) Migration and climate change: examining thresholds of change to guide effective adaptation decision-making. Popul Environ 32:238–262. doi:10.1007/s11111-010-0126-9
Black R, Adger WN, Arnell NW, Dercon S, Geddes A, Thomas D (2011) The effect of environmental change on human migration 21. Glob Environ Change 21:S3–S11. doi:10.1016/j.gloenvcha.2011.10.001
Bonilla-Moheno M, Aide TM, Clark M (2012) The influence of socioeconomic, environmental, and demographic factors on municipality-scale land-cover change in Mexico. Reg Environ Change 12:543–557. doi:10.1007/s10113-011-0268-z
Carr DL (2004) Proximate population factors and deforestation in tropical agricultural frontiers. Popul Environ 25:585–612. doi:10.1023/B:POEN.0000039066.05666.8d
CSA (2007) Population and housing census. Central Statistical Agency, Addis Ababa
Dardel C, Kergoat L, Hiernaux P, Grippa M, Mougin E, Ciais P, Nguyen C-C (2014) Rain-use-efficiency: What it Tells us about the conflicting Sahel greening and Sahelian paradox. Remote Sens 6:3446. doi:10.3390/rs6043446
Dent D, Bai Z, Schaepman M, Olsson L (2009) Letter to the editor. Soil Use Manag 25:93–97. doi:10.1111/j.1475-2743.2009.00197.x
Dessie G, Christiansson C (2008) Forest decline and its causes in the south-central rift valley of Ethiopia: human Impact over a one hundred year perspective. AMBIO: A J Hum Environ 37:263–271. doi:10.1579/0044-7447(2008)372.0.co;2
Erb K-H, Krausmann F, Gaube V, Gingrich S, Bondeau A, Fischer-Kowalski M, Haberl H (2009) Analyzing the global human appropriation of net primary production—processes, trajectories, implications. An introduction. Ecol Econ 69:250–259. doi:10.1016/j.ecolecon.2009.07.001
Erulkar AS, Mekbib TA, Simie N, Gulema T (2006) Migration and vulnerability among adolescents in slum areas of Addis Ababa, Ethiopia. J Youth Stud 9:361–374. doi:10.1080/13676260600805697
Ezra M (2001) Demographic responses to environmental stress in the drought-and famine-prone areas of northern Ethiopia. Int J Popul Geogr 7:259–279. doi:10.1002/ijpg.226
Ezra M, Kiros G-E (2001) Rural out-migration in the drought prone areas of Ethiopia: a multilevel analysis. Int Migr Rev 35:749–771. doi:10.1111/j.1747-7379.2001.tb00039.x
Farr TG, Rosen PA, Caro E, Crippen R, Duren R, Hensley S, Kobrick M, Paller M, Rodriguez E, Roth L (2007) The shuttle radar topography mission. Rev Geophys. doi:10.1029/2005RG000183
Fensholt R, Rasmussen K, Kaspersen P, Huber S, Horion S, Swinnen E (2013) Assessing land degradation/recovery in the african sahel from long-term earth observation based primary productivity and precipitation relationships. Remote Sens 5:664. doi:10.3390/rs5020664
Foresight (2011) Migration and global environmental change: Future challenges and opportunities. The Government Office for Science, London
Gang C, Zhou W, Chen Y, Wang Z, Sun Z, Li J, Qi J, Odeh I (2014) Quantitative assessment of the contributions of climate change and human activities on global grassland degradation. Environ Earth Sci 72:4273–4282. doi:10.1007/s12665-014-3322-6
Geist HJ, Lambin EF (2002) Proximate causes and underlying driving forces of tropical deforestation tropical forests are disappearing as the result of many pressures, both local and regional, acting in various combinations in different geographical locations. Bioscience 52:143–150. doi:10.1641/0006-3568(2002)052[0143:PCAUDF]2.0.CO;2
Geist HJ, Lambin EF (2004) Dynamic causal patterns of desertification. Bioscience 54:817–829. doi:10.1641/0006-3568(2004)054[0817:DCPOD]2.0.CO;2
Gemedo D, Maass BL, Isselstein J (2006) Rangeland condition and trend in the semi-arid Borana lowlands, southern Oromia, Ethiopia. Afr J Range Forage Sci 23:49–58. doi:10.2989/10220110609485886
Gray C, Müller V (2012) Drought and population mobility in rural Ethiopia. World Dev 40:134–145. doi:10.1016/j.worlddev.2011.05.023
Haberl H, Erb KH, Krausmann F, Gaube V, Bondeau A, Plutzar C, Gingrich S, Lucht W, Fischer-Kowalski M (2007) Quantifying and mapping the human appropriation of net primary production in earth’s terrestrial ecosystems. Proc Natl Acad Sci 104:12942–12947. doi:10.1073/pnas.0704243104
Haileslassie A, Priess J, Veldkamp E, Teketay D, Lesschen JP (2005) Assessment of soil nutrient depletion and its spatial variability on smallholders’ mixed farming systems in Ethiopia using partial versus full nutrient balances. Agric Ecosyst Environ 108:1–16. doi:10.1016/j.agee.2004.12.010
Henry S, Boyle P, Lambin EF (2003) Modelling inter-provincial migration in Burkina Faso, West Africa: the role of socio-demographic and environmental factors. Appl Geogr 23:115–136. doi:10.1016/j.apgeog.2002.08.001
Higginbottom TP, Symeonakis E (2014) Assessing land degradation and desertification using vegetation index data: current frameworks and future directions. Remote Sens 6:9552–9575. doi:10.3390/rs6109552
Imhoff ML, Bounoua L, Ricketts T, Loucks C, Harriss R, Lawrence WT (2004) Global patterns in human consumption of net primary production. Nature 429:870–873. doi:10.1038/nature02619
Lemenih M, Kassa H, Kassie G, Abebaw D, Teka W (2014) Resettlement and woodland management problems and options: a case study from North-western Ethiopia. Land Degrad Dev 25:305–318. doi:10.1002/ldr.2136
Ma T, Zhou C, Pei T (2012) Simulating and estimating tempo-spatial patterns in global human appropriation of net primary production (HANPP): a consumption-based approach. Ecol Indic 23:660–667. doi:10.1016/j.ecolind.2012.05.026
Mena CF, Bilsborrow RE, McClain ME (2006) Socioeconomic drivers of deforestation in the Northern Ecuadorian Amazon. Environ Manag 37:802–815. doi:10.1007/s00267-003-0230-z
Meshesha D, Tsunekawa A, Tsubo M, Ali S, Haregeweyn N (2014) Land-use change and its socio-environmental impact in Eastern Ethiopia’s highland. Reg Environ Change 14:757–768. doi:10.1007/s10113-013-0535-2
Meze-Hausken E (2000) Migration caused by climate change: how vulnerable are people inn dryland areas? Mitig Adapt Strateg Glob Change 5:379–406. doi:10.1023/a:1026570529614
Meze-Hausken E (2008) On the (im-)possibilities of defining human climate thresholds. Clim Change 89:299–324. doi:10.1007/s10584-007-9392-7
Milesi C, Hashimoto H, Running SW, Nemani RR (2005) Climate variability, vegetation productivity and people at risk. Glob Planet Change 47:221–231. doi:10.1016/j.gloplacha.2004.10.020
Mitchell TD, Jones PD (2005) An improved method of constructing a database of monthly climate observations and associated high-resolution grids. Int J Climatol 25:693–712. doi:10.1002/joc.1181
Morrissey JW (2013) Understanding the relationship between environmental change and migration: the development of an effects framework based on the case of northern Ethiopia. Glob Environ Change 23:1501–1510. doi:10.1016/j.gloenvcha.2013.07.021
Morton JF (2007) The impact of climate change on smallholder and subsistence agriculture. Proc Natl Acad Sci 104:19680–19685. doi:10.1073/pnas.0701855104
Neumann K, Hermans F (2015) What drives human migration in the Sahelian countries? A meta-analysis. Popul Space Place 23(1):e1962. doi:10.1002/psp.1962
Neumann K, Hilderink H (2015) Opportunities and challenges for investigating the environment-migration nexus. Hum Ecol 43:309–322. doi:10.1007/s10745-015-9733-5
Osbah H, Twyman C, Adger WN, Thomas D (2010) Evaluating successful livelihood adaptation to climate variability and change in Southern Africa. Ecology and Society 15(2):27
Ouedraogo I, Tigabu M, Savadogo P, Compaoré H, Odén P, Ouadba J (2010) Land cover change and its relation with population dynamics in Burkina Faso, West Africa. Land Degrad Dev 21:453–462. doi:10.1002/ldr.981
Pricope NG, Husak G, Lopez-Carr D, Funk C, Michaelsen J (2013) The climate-population nexus in the East African Horn: emerging degradation trends in rangeland and pastoral livelihood zones. Glob Environ Change 23:1525–1541. doi:10.1016/j.gloenvcha.2013.10.002
Reid RS, Kruska RL, Muthui N, Taye A, Wotton S, Wilson CJ, Mulatu W (2000) Land-use and land-cover dynamics in response to changes in climatic, biological and socio-political forces: the case of southwestern Ethiopia. LandscEcol 15:339–355. doi:10.1023/A:1008177712995
Reuveny R (2007) Climate change-induced migration and violent conflict. Polit Geogr 26:656–673. doi:10.1016/j.polgeo.2007.05.001
Running SW, Nemani RR, Heinsch FA, Zhao M, Reeves M, Hashimoto H (2004) A continuous satellite-derived measure of global terrestrial primary production. Bioscience 54:547–560. doi:10.1641/0006-3568(2004)054[0547:ACSMOG]2.0.CO;2
Sissoko K, van Keulen H, Verhagen J, Tekken V, Battaglini A (2011) Agriculture, livelihoods and climate change in the West African Sahel. Reg Environ Change 11:119–125. doi:10.1007/s10113-010-0164-y
Solomon TB, Snyman HA, Smit GN (2007) Cattle-rangeland management practices and perceptions of pastoralists towards rangeland degradation in the Borana zone of southern Ethiopia. J Environ Manag 82:481–494. doi:10.1016/j.jenvman.2006.01.008
Thompson MV, Randerson JT, Malmstrom CM, Field CB (1996) Change in net primary production and heterotrophic respiration: How much is necessary to sustain the terrestrial carbon sink? Global Biogeochem Cycles 10(4):711–726. doi:10.1029/96GB01667
Tsegaye D, Moe SR, Vedeld P, Aynekulu E (2010) Land-use/cover dynamics in Northern Afar rangelands, Ethiopia. Agric Ecosyst Environ 139:174–180. doi:10.1016/j.agee.2010.07.017
Van der Geest K, Vrieling A, Dietz T (2010) Migration and environment in Ghana: a cross-district analysis of human mobility and vegetation dynamics. Environ Urban 22:107–123. doi:10.1177/0956247809362842
Wessels K (2009) Letter to the editor: comments on ‘Proxy global assessment of land degradation’ by Bai et al. (2008). Soil Use Manag 25(1):91–92. doi:10.1111/j.1475-2743.2009.00195.x
Wessels KJ, Prince SD, Malherbe J, Small J, Frost PE, VanZyl D (2007) Can human-induced land degradation be distinguished from the effects of rainfall variability? A case study in South Africa. J Arid Environ 68:271–297. doi:10.1016/j.jaridenv.2006.05.015
Wessels KJ, van den Bergh F, Scholes RJ (2012) Limits to detectability of land degradation by trend analysis of vegetation index data. Remote Sens Environ 125:10–22. doi:10.1016/j.rse.2012.06.022
Zhao M, Running SW (2010) Drought-induced reduction in global terrestrial net primary production from 2000 through 2009. Science 329:940–943. doi:10.1126/science.1192666
Zika M, Erb K-H (2009) The global loss of net primary production resulting from human-induced soil degradation in drylands. Ecol Econ 69:310–318. doi:10.1016/j.ecolecon.2009.06.014
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KNH acknowledges a VENI grant from the Netherlands Organisation for Scientific Research (NWO) and funding from the German Federal Ministry of Education and Research (BMBF) within the project MigSoKo (01UU1606).
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Hermans-Neumann, K., Priess, J. & Herold, M. Human migration, climate variability, and land degradation: hotspots of socio-ecological pressure in Ethiopia. Reg Environ Change 17, 1479–1492 (2017). https://doi.org/10.1007/s10113-017-1108-6
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DOI: https://doi.org/10.1007/s10113-017-1108-6