Does poverty cause land degradation and desertification, or vice-versa? Or are they parts of a feedback loop? This issue is controversial. Whether the poor are major agents of desertification or not, it is clear that they suffer especially from its consequences because they are highly dependent on the land's productivity for their livelihoods (Hazell et al. 2002).
Cleaver and Schreiber (1994) hypothesized that poverty, overpopulation and land degradation create a self-reinforcing downward spiral leading to ever-greater misery and land degradation. Farmers may be 'mining' their soils of nutrients and vegetative cover without replacing them, triggering soil erosion and productivity decline - although the extent and importance of soil mining is still an issue of debate.
But the opposite dynamic has also been proposed. In the 'induced innovation' concept of Boserup (1965), increasing populations stimulate increasing demand for agricultural products. As land becomes more costly compared to labor, incentives emerge for more intensive, yet sustainable land management in order to reap the benefits of the enlarged market opportunity year after year.
Both downward-spiral and induced-innovation scenarios have been reported under different situations (Pender 1998). Cases of the downward spiral were described by Durning (1989), Leonard (1989), Lopez (1998), Kates and Haarmann (1992), Mink (1993), Ram et al. (1999) and White and Jickling (1995). Induced innovation has been reported by Leach and Mearns (1996), Mortimore and Adams (1999), Templeton and Scherr (1999), Tiffen (2002), Tiffen et al. (1994), Tiffen and Mortimore (2002), and Wiggins (1995).
Comparing the downward-spiral vs. induced-innovation evidence, it appears that outcomes largely depend on how well societies adapt to rapid population growth, globalization, market development, technological change, climate change, and agro-ecological conditions (Heath and Binswanger 1996; Jodha 1998; Lele and Stone 1989; Kuyvenhoven and Ruben 2002; Lopez 1998; Mazzucato and Niemeijer 2002; Mortimore and Harris 2004; Niemeijer and Mazzucato 2002a; Pender et al. 2001a; Prakash 1997; Scherr 2000).
Both of these models may be true at different times for the same area of land. Tiffen and Bunch (2002) suggest a general pattern of development in Africa which begins from extensive, low-intensity animal herding; gradually degrading the land as populations of humans and animals increase; but ultimately recovering as dense human populations create markets for agricultural produce that must be met by rehabilitating the limited remaining land area available for farming.
Intensification of land use, even if it is sustainable does not necessarily imply that poverty will be reduced. If more labor-productive systems are not employed, then wages cannot increase or may decrease due to the increased availability of labor.
This is why the cases of successful poverty escape exhibit productivity-increasing dynamics such as:
- The exploitation of local comparative advantages (soil, climate, biodiversity, labor, etc.)
- The use of technologies that increase land and labor productivity faster than population growth; and
- Improved access to growing markets (Hazell and Haddad 2001; Pender, 1998; Pender et al. 2001b).
Return to "What causes desertification?
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