221
9
Africa also have come to (Prudencio 1993; Ramisch 2005; Tittonell et al. 2007).
This example of cotton production in Mali also shows how market access can act
as a driving force in agricultural development in line with the study by Tiffen et al.
(1994), and it demonstrates that cash-crop cotton cultivation does not necessarily
result in exhaustion of soil nutrients.
Marx is sometimes quoted for having said that ‘… all progress in capitalist agriculture is a progress in the art, not only of robbing the worker, but of robbing the soil’
(Marx 1990: 638). Influenced by this idea, it has often been argued in political ecology
and development studies more broadly, that the production of commodities for a
market necessarily will lead to environmental degradation. This should, however, be
treated as a hypothesis to be empirically investigated, rather than as a priori fact.
Methods
This box describes the methods used in a study of soil fertility change in the Malian
cotton zone by Benjaminsen et al. (2010). Since there was no baseline dataset to
compare with, this study had to settle for the spatial analogue method, which consists of comparing soil properties on different sites with varying histories of land
use. The main independent variable used was length of fallow. The study did not
focus on the effects of cotton production on soil fertility per se, but rather on the
varying intensity of the cotton–cereal rotation and how this intensity impacts on
soil fertility.
Soil data from cultivated fields were compared with data from fallows of different lengths. In addition, samples were taken on woodland as well as in sacred
groves (with permission from the village chief). The woodlands and sacred groves
had never been cultivated, but the woodland sites had been grazed. It should also
be noted that the sacred groves are usually centrally situated in the villages on
some of the best soils. They therefore represent very valuable reference sites being
as close to a natural system one can get in terms of soil fertility. The strength of
this method is its ability to account for spatial effects of cultivation. Soil fertility is
typically higher in the vicinity of the homestead and decreases as the distance from
the homestead increases (Prudencio 1993; Ramisch 2005). The soil samples taken
from woodlands are distant from the homestead whereas samples taken from
cultivated fields and fields under fallow represent soils that are more adjacent to
the homestead.
In total, 273 soil samples were collected in 19 villages from north to south in
the cotton zone (. Fig. 9.1) to cover diversities in agricultural development in the
region. The selection was based on the zoning of the cotton zone made by CMDT,
where the different sub-zones represent different land use intensities. Following
this zoning, the 19 villages were grouped into five different ‘gradients’, from 1 to 5,
with 1 having the highest land use intensity and 5 the lowest.
9.1 · Population Growth and Agricultural Development in Africa
9
Africa also have come to (Prudencio 1993; Ramisch 2005; Tittonell et al. 2007).
This example of cotton production in Mali also shows how market access can act
as a driving force in agricultural development in line with the study by Tiffen et al.
(1994), and it demonstrates that cash-crop cotton cultivation does not necessarily
result in exhaustion of soil nutrients.
Marx is sometimes quoted for having said that ‘… all progress in capitalist agriculture is a progress in the art, not only of robbing the worker, but of robbing the soil’
(Marx 1990: 638). Influenced by this idea, it has often been argued in political ecology
and development studies more broadly, that the production of commodities for a
market necessarily will lead to environmental degradation. This should, however, be
treated as a hypothesis to be empirically investigated, rather than as a priori fact.
Methods
This box describes the methods used in a study of soil fertility change in the Malian
cotton zone by Benjaminsen et al. (2010). Since there was no baseline dataset to
compare with, this study had to settle for the spatial analogue method, which consists of comparing soil properties on different sites with varying histories of land
use. The main independent variable used was length of fallow. The study did not
focus on the effects of cotton production on soil fertility per se, but rather on the
varying intensity of the cotton–cereal rotation and how this intensity impacts on
soil fertility.
Soil data from cultivated fields were compared with data from fallows of different lengths. In addition, samples were taken on woodland as well as in sacred
groves (with permission from the village chief). The woodlands and sacred groves
had never been cultivated, but the woodland sites had been grazed. It should also
be noted that the sacred groves are usually centrally situated in the villages on
some of the best soils. They therefore represent very valuable reference sites being
as close to a natural system one can get in terms of soil fertility. The strength of
this method is its ability to account for spatial effects of cultivation. Soil fertility is
typically higher in the vicinity of the homestead and decreases as the distance from
the homestead increases (Prudencio 1993; Ramisch 2005). The soil samples taken
from woodlands are distant from the homestead whereas samples taken from
cultivated fields and fields under fallow represent soils that are more adjacent to
the homestead.
In total, 273 soil samples were collected in 19 villages from north to south in
the cotton zone (. Fig. 9.1) to cover diversities in agricultural development in the
region. The selection was based on the zoning of the cotton zone made by CMDT,
where the different sub-zones represent different land use intensities. Following
this zoning, the 19 villages were grouped into five different ‘gradients’, from 1 to 5,
with 1 having the highest land use intensity and 5 the lowest.
9.1 · Population Growth and Agricultural Development in Africa