Agricultural Expansion Drivers and Constraints: Comparison
Please note this is a comparison between Version 1 by Nugun Patrick Jellason and Version 2 by Vicky Zhou.

Agricultural expansion refers to the conversion of uncultivated land, including natural forests, woodlands, grasslands and wetlands into crop or grazing land, and may be undertaken by smallholders or largescale farmers. 

  • agricultural expansion
  • drivers
  • Sub-Saharan Africa
  • conservation
  • constraints

1. Introduction

Population growth and rising incomes are generating ever greater demands on agriculture to supply food, fuel, fibre, and animal feed [1][2]. As the global population is projected to reach approximately 10 billion by 2050, of which around 2 billion will be in sub-Saharan Africa (SSA), it is likely that these demands will only increase further, putting pressure on the natural environment [3][4][5]. The intensification of agricultural practices and agricultural expansion have both contributed to meeting these increasing demands [6][7][8][9][10]. Agricultural expansion, defined as the conversion of natural vegetation to land-use for agriculture [7], that occurred in the 1980s and 1990s has resulted in an increase in the area under food production in SSA and increased opportunities for income-generation and food security [6]. However, this expansion may also threaten a wider array of provisioning and regulating ecosystem services that are provided by areas of natural vegetation [6][11][12][13][14][15]. Given the increasing pressure on agricultural land and the impacts of agricultural expansion on livelihoods and ecosystem services, a better understanding of the drivers of agricultural expansion in SSA, where a driver in this context is defined as any factor that alters “an aspect of an ecosystem” [15][16], is both imperative and timely.

Agricultural expansion into natural vegetation, such as grasslands, woodlands or forests [6][8][17] is typically a non-linear process [18][19] and caused by different factors, such as market incentives and institutional arrangements [20]. That expansion may be to increase crop or grazing land [21], and whether it occurs is influenced by both bio-physical aspects of the landscape, a weak or strong land governance [22]. A growing body of evidence on the drivers of land-use change, including drivers of agricultural expansion, can be found at the global and regional scale [18][23][24]. However, there has been limited research on the drivers of agricultural expansion specific to SSA compared with other regions of the world [21].

Understanding current trends, and drivers of agricultural expansion and their interactions can support policy decisions for better management of future agricultural development, forests and other natural habitats, at local and regional levels [25][26][27].

2. Perspectives on Agricultural Expansion Drivers, Pathways, and Constraints

In this section, we highlight and classify key drivers of agricultural expansion. These drivers can be categorised as either proximate or underlying [24]; have different spatial and temporal dimensions [28][29]; and differ depending on the scale of agriculture [23]. Proximate drivers are also referred to in the literature as direct drivers, and underlying drivers as indirect drivers.

A proximate driver is an immediate activity or human action that has a direct impact on vegetation cover [24]. An example of a biophysical proximate driver could be declining on-farm soil fertility [21]. Underlying drivers include institutional, economic, and socio- demographic factors, that influence the proximate drivers [15]. For example, a proximate driver of land-use change such as infrastructural development may be in response to underlying drivers, such as population growth and changes in consumption patterns [15][30]. However, considerations of factors as proximate and underlying drivers may differ, depending on context or scope of a study. The interactions of proximate and underlying drivers together affect the overall system [29]. Briefly, we introduce institutional, economic, and socio-demographic drivers for agricultural expansion below.

Institutional drivers can be considered as rules, policies, or international agreements that may affect agriculture-related land-use change [31]. For example, in Latin America, MERCOSUR, the South American free trade agreement, has been identified as an important underlying driver of agricultural expansion in the region [32]. More broadly, agricultural expansion may be driven by export-led agricultural commodity production [32] and international agricultural trade flows [33].

Economic drivers of agricultural expansion are often linked to the relative marginal private values of agricultural and non-agricultural land, and the costs of converting non-agricultural land. Increased profitability of croplands, through increased efficiency from agricultural technological developments [21], and reduced costs of market access through better infrastructure and information flow, have been identified as important drivers for agricultural expansion [34]. Foreign direct investments in agriculture for feed and fuel crops have also been identified as creating incentives for agricultural expansion [35][36]. The introduction of agricultural technology can encourage agricultural land expansion likened to the Jevon’s Paradox phenomenon as witnessed in Brazil [37].

Socio-demographic drivers, whether local, national, or global, also influence agricultural expansion. At the local level, examples include the combination of high rates of population growth and subsistence farming [32]. Similarly, migration or changes in sectoral employment can drive changes in land use towards or away from agriculture [38]. While, urbanisation may result in the direct loss of farmland, it can be a driver of agricultural expansion elsewhere as individuals look for alternate locations to farm [39]. Generally, socio-demographic drivers such as dietary shifts, reflected in an increased consumption of meat leading to a rise in demand for animal feed and pasture, can also drive an increase in demand for agricultural land [2][40]. In Mexico, Mendoza-Ponce, Corona-Núñez [41] found that distance from human settlements, roads, population density, gross domestic product (GDP), and marginalization all drove agricultural expansion into forestland, while access to water drove agricultural expansion into grassland.

Just as there are drivers of agricultural expansion, so too are there factors that can constrain or slowdown agricultural expansion in to areas of natural vegetation [42]. These include a broad range of approaches to strengthening governance over non-cultivated lands; making use of ‘protected status’ designation; and enforcing existing restrictions and regulation [43]. Weak governance more generally has been found to likely result in considerable loss of areas that are designated “protected” from agricultural expansion [22][44]. Increasing the private value of non-agricultural land, such as through payments for ecosystem services (PES), can allow landowners to receive additional economic benefits from non-agricultural land, thereby, creating an economic incentive not to convert natural lands to agricultural lands. However, the current reality in many low and middle income countries (LMICs) is that protection of forest and other non-cultivated land is difficult due to low incentives for communities to protect, high costs of enforcement, and highly constrained government budgets [45]. Within communities, there are also competing demands between those whose livelihoods rely heavily on resources, such as non-timber forest products harvested from natural habitats, and those whose livelihoods rely on agricultural crops [45].

3. Conclusions

Agricultural land expansion for the production of both food and cash crops, such as maize, rice, soybeans and oil palm has been at the expense of natural habitats, often intact or disturbed forests, and grasslands. Across the different SSA countries, proximate drivers, such as soil fertility decline, climate change and variability, access to services, demand for food and fuel, constitute important drivers of agricultural expansion. Underlying drivers such as population dynamic and human resettlement, demand for agricultural land, government policies, accessibility/distance to market, increase in prices of agricultural products, increased income, land tenure operating at both micro and macro levels are likely to indirectly cause agricultural expansion. In addition, certain factors such as effective law enforcement, endemic pests and diseases, conflict and insecurity, productivity uncertainty, culture, cost of land clearing, agricultural inputs subsidies availability can place restraints on agricultural expansion. The location-specific influences, and interactions between the drivers, are still insufficiently understood. Yet, that understanding is critically important for managing land-use trade-offs in the future. Further, as drivers of agricultural expansion are better understood, it is equally important to address the presence or absence of constraining factors that play a key role in determining whether area expansion can occur or not.

Knowledge of the various levels of interactions of drivers and constraints can also aid policy makers that have the difficult task of balancing increased food production with the potential loss of ecosystem services where that increased production is through agricultural expansion into natural habitats. This will also have a direct bearing on biodiversity conservation, prediction of future trends and to mitigate future impacts that could hamper the provision of ecosystem services.

References

  1. Alexander, P.; Rounsevell, M.D.A.; Dislich, C.; Dodson, J.R.; Engström, K.; Moran, D. Drivers for global agricultural land use change: The nexus of diet, population, yield and bioenergy. Glob. Environ. Chang. 2015, 35, 138–147.
  2. Alexandratos, N.; Bruinsma, J. World Agriculture towards 2030/2050: The 2012 Revision; ESA Working Papers 12-03; Food and Agriculture Organization of the United Nations: Rome, Italy, 2012; p. 160.
  3. UNDESA. World Population Prospects. 2019. Available online: (accessed on 20 March 2020).
  4. van Ittersum, M.K.; van Bussel, L.G.J.; Wolf, J.; Grassini, P.; van Wart, J.; Guilpart, N.; Claessens, L.; de Groot, H.; Wiebe, K.; Mason-D’Croz, D.; et al. Can sub-Saharan Africa feed itself? Proc. Natl. Acad. Sci. USA 2016, 113, 14964.
  5. Leroux, L.; Bégué, A.; Lo Seen, D.; Jolivot, A.; Kayitakire, F. Driving forces of recent vegetation changes in the Sahel: Lessons learned from regional and local level analyses. Remote Sens. Environ. 2017, 191, 38–54.
  6. Gibbs, H.K.; Ruesch, A.S.; Achard, F.; Clayton, M.K.; Holmgren, P.; Ramankutty, N.; Foley, J.A. Tropical forests were the primary sources of new agricultural land in the 1980s and 1990s. Proc. Natl. Acad. Sci. USA 2010, 107, 16732.
  7. Arvor, D.; Meirelles, M.; Dubreuil, V.; Bégué, A.; Shimabukuro, Y.E. Analyzing the agricultural transition in Mato Grosso, Brazil, using satellite-derived indices. Appl. Geogr. 2012, 32, 702–713.
  8. Byerlee, D.; Stevenson, J.; Villoria, N. Does intensification slow crop land expansion or encourage deforestation? Glob. Food Secur. 2014, 3, 92–98.
  9. Chamberlin, J.; Jayne, T.S.; Headey, D. Scarcity amidst abundance? Reassessing the potential for cropland expansion in Africa. Food Policy 2014, 48, 51–65.
  10. Maitima, J.; Mugatha, S.; Reid, R.; Gachimbi, L.; Majule, A.; Lyaruu, H.; Pomery, D.; Mathai, S.; Mugisha, S. The linkages between land use change, land degradation and biodiversity across East Africa. Afr. J. Environ. Sci. Technol. 2009, 3, 310–325.
  11. Laurance, W.F.; Sayer, J.; Cassman, K.G. Agricultural expansion and its impacts on tropical nature. Trends Ecol. Evol. 2014, 29, 107–116.
  12. Newbold, T.; Hudson, L.N.; Hill, S.L.L.; Contu, S.; Lysenko, I.; Senior, R.A.; Börger, L.; Bennett, D.J.; Choimes, A.; Collen, B.; et al. Global effects of land use on local terrestrial biodiversity. Nature 2015, 520, 45–50.
  13. Reed, J.; van Vianen, J.; Foli, S.; Clendenning, J.; Yang, K.; MacDonald, M.; Petrokofsky, G.; Padoch, C.; Sunderland, T. Trees for life: The ecosystem service contribution of trees to food production and livelihoods in the tropics. For. Policy Econ. 2017, 84, 62–71.
  14. FAO. The State of the World’s Forests 2018: Forest Pathways to Sustainable Development; Food and Agriculture Organisation of the United Nations: Rome, Italy, 2018.
  15. IPBES. Global Assessment Report on Biodiversity and Ecosystem Services of the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services; Brondizio, E.S., Settele, J., Díaz, S., Ngo, H.T., Eds.; IPBES Secretariat: Bonn, Germany, 2019.
  16. MA, M.A. Ecosystems and Human Well-Being: A Framework for Assessment; Hassan, R., Scholes, R., Ash, N., Eds.; Millennium Ecosystem Assessment (MA): Washington, DC, USA, 2003.
  17. Shoyama, K.; Braimoh, A.K.; Avtar, R.; Saito, O. Land Transition and Intensity Analysis of Cropland Expansion in Northern Ghana. Environ. Manag. 2018, 62, 892–905.
  18. Lambin, E.F.; Meyfroidt, P. Land use transitions: Socio-ecological feedback versus socio-economic change. Land Use Pol. 2010, 27, 108–118.
  19. Qasim, M.; Hubacek, K.; Termansen, M. Underlying and proximate driving causes of land use change in district Swat, Pakistan. Land Use Pol. 2013, 34, 146–157.
  20. Lambin, E.F.; Turner, B.L.; Geist, H.J.; Agbola, S.B.; Angelsen, A.; Bruce, J.W.; Coomes, O.T.; Dirzo, R.; Fischer, G.; Folke, C.; et al. The causes of land-use and land-cover change: Moving beyond the myths. Glob. Environ. Chang. 2001, 11, 261–269.
  21. Piquer-Rodríguez, M.; Butsic, V.; Gärtner, P.; Macchi, L.; Baumann, M.; Gavier Pizarro, G.; Volante, J.N.; Gasparri, I.N.; Kuemmerle, T. Drivers of agricultural land-use change in the Argentine Pampas and Chaco regions. Appl. Geogr. 2018, 91, 111–122.
  22. Peres, C.; Schneider, M. Subsidized agricultural resettlements as drivers of tropical deforestation. Biol. Conserv. 2012, 151.
  23. Serneels, S.; Lambin, E.F. Proximate causes of land-use change in Narok District, Kenya: A spatial statistical model. Agric. Ecosyst. Environ. 2001, 85, 65–81.
  24. Geist, H.J.; Lambin, E.F. 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 2002, 52, 143–150.
  25. Dimobe, K.; Ouédraogo, A.; Soma, S.; Goetze, D.; Porembski, S.; Thiombiano, A. Identification of driving factors of land degradation and deforestation in the Wildlife Reserve of Bontioli (Burkina Faso, West Africa). Glob. Ecol. Conserv. 2015, 4, 559–571.
  26. van Vliet, J.; de Groot, H.L.F.; Rietveld, P.; Verburg, P.H. Manifestations and underlying drivers of agricultural land use change in Europe. Landsc. Urban Plan. 2015, 133, 24–36.
  27. MA, M.A. Ecosystems and Human Well-Being: Our Human Planet: Summary for Decision Makers; Island Press: Washington, DC, USA, 2005.
  28. Reid, R.S.; Kruska, R.L.; Muthui, N.; Taye, A.; Wotton, S.; Wilson, C.J.; Mulatu, W. Land-use and land-cover dynamics in response to changes in climatic, biological and socio-political forces: The case of southwestern Ethiopia. Landsc. Ecol. 2000, 15, 339–355.
  29. Gusenbauer, D.; Franks, P. Agriculture, Nature Conservation or Both? Managing Trade-Offs and Synergies in Sub-Saharan Africa; International Institute for Environment and Development (IIED): London, UK, 2019.
  30. Mariwah, S.; Osei, K.N.; Amenyo-Xa, M.S. Urban land use/land cover changes in the Tema metropolitan area (1990–2010). GeoJournal 2017, 82, 247–258.
  31. Wollenberg, E.K.; Campbell, B.M.; Nihart, A.; Holmgren, P.; Seymour, F.; Sibanda, L.; von Braun, J. Actions Needed to Halt Deforestation and Promote Climate-Smart Agriculture. In Greenhouse Gas Market Report 2011 Asia and Beyond: The Roadmap to Global Carbon & Energy Markets; Peetermans, J., Ed.; International Emissions Trading Association Genève: Genève, Switzerland, 2011; pp. 95–100.
  32. Mattison, E.H.A.; Norris, K. Bridging the gaps between agricultural policy, land-use and biodiversity. Trends Ecol. Evol. 2005, 20, 610–616.
  33. Henders, S.; Ostwald, M. Accounting methods for international land-related leakage and distant deforestation drivers. Ecol. Econ. 2014, 99, 21–28.
  34. Puri, J. Factors Affecting Agricultural Expansion in Forest Reserves of Thailand: The Role of Population and Roads. Ph.D. Thesis, University of Maryland, College Park, MD, USA, 2006.
  35. Nepstad, D.C.; Stickler, C.M. Managing the Tropical Agriculture Revolution. J. Sustain. For. 2008, 27, 43–56.
  36. Reinertsen, H.L. Food vs. Non-Food Crops: Changes in Areas and Yields 1992 to 2016. Master’s Thesis, Norwegian University of Life Sciences, Ås, Norway, 2018.
  37. Ceddia, M.G.; Zepharovich, E. Jevons paradox and the loss of natural habitat in the Argentinean Chaco: The impact of the indigenous communities’ land titling and the Forest Law in the province of Salta. Land Use Pol. 2017, 69, 608–617.
  38. Munteanu, C.; Kuemmerle, T.; Boltiziar, M.; Butsic, V.; Gimmi, U.; Lúboš, H.; Kaim, D.; Király, G.; Konkoly-Gyuró, É.; Kozak, J.; et al. Forest and agricultural land change in the Carpathian region—A meta-analysis of long-term patterns and drivers of change. Land Use Pol. 2014, 38, 685–697.
  39. Esbah, H. Land Use Trends During Rapid Urbanization of the City of Aydin, Turkey. Environ. Manag. 2007, 39, 443–459.
  40. Mateo-Sagasta, J.; Zadeh, S.M. Global Drivers of Water Pollution from Agriculture. In More People, More Food, Worse Water? A Global Review of Water Pollution from Agriculture; Mateo-Sagasta, J., Zadeh, S.M., Turral, H., Eds.; Food and Agriculture Organization of the United Nations (FAO) & International Water Management Institute (IWMI): Rome, Italy, 2018; pp. 15–38.
  41. Mendoza-Ponce, A.; Corona-Núñez, R.O.; Galicia, L.; Kraxner, F. Identifying hotspots of land use cover change under socioeconomic and climate change scenarios in Mexico. Ambio 2019, 48, 336–349.
  42. Jayne, T.; Chapoto, A.; Sitko, N.; Nkonde, C.; Muyanga, M.; Chamberlin, J. Is the Scramble for Land in Africa Foreclosing a Smallholder Agricultural Expansion Strategy? J. Int. Aff. 2014, 67, 35–53.
  43. Sassen, M.; Sheil, D.; Giller, K.E.; ter Braak, C.J.F. Complex contexts and dynamic drivers: Understanding four decades of forest loss and recovery in an East African protected area. Biol. Conserv. 2013, 159, 257–268.
  44. Keenan, R.J.; Reams, G.A.; Achard, F.; de Freitas, J.V.; Grainger, A.; Lindquist, E. Dynamics of global forest area: Results from the FAO Global Forest Resources Assessment 2015. For. Ecol. Manag. 2015, 352, 9–20.
  45. Robinson, E.J.Z.; Kumar, A.M.; Albers, H.J. Protecting Developing Countries’ Forests: Enforcement in Theory and Practice. J. Nat. Resour. Policy Res. 2010, 2, 25–38.
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