| authors | Rietkerk, M.G.; Blijdorp, R.R.S.; Slingerland, M. |
| source | Agroforestry Systems, Volume: 41, Issue: 2 (1998), pp. 201-211 |
| full text | [Full text]
|
| publisher | Springer |
| URL publisher | [Website publisher]
|
| document type | Article |
| disciplines | Milieukunde |
| abstract | The tree-shrub savanna ‘Forêt Classée de Nazinon’ (Burkina Faso) is submitted to a
management of grazing and rotational cutting of Detarium microcarpum. This species resprouts
after cutting. In order to investigate whether this silvopastoral land use system is sustainable,
aboveground herbaceous biomass was measured on subplots under uncut trees (‘uncut’), next
to the stubs of cut trees (‘cut’) and on subplots not influenced by the (former) crowns of trees
(‘open grassland’) in four lots. These lots were cut one, three, six and seven years before the
study. Vegetation composition of the lots and the composition of the diet of cattle were also
determined. Comparisons were made between treatments and lots. Herbaceous biomass was
lower in the open grassland subplots than in uncut or cut subplots. We speculate that soil enrichment
and more efficient precipitation input in (former) tree crown zones could have resulted in
this pattern. Cutting and subsequent resprouting of trees did not lead to significant differences
in herbaceous biomass between cut and uncut subplots. The most simple explanation for this is
that the trees could extend their roots beyond the location of their neighbouring trees. Biomass
and coverage of perennial grasses, mainly Andropogon ascinodis and Andropogon gayanus,
did not change in lots cut one, three or six years before the study, but decreased dramatically
in lots that were cut seven years before the study. When foraging, cattle spent more than 90%
of their time feeding on these species. This indicates that, as a consequence of tree cutting, forage
availability may be reduced to the point where local herdsmen are forced to take their cattle to
another region. |
| keywords | bush encroachment, grazing, silvopastoralism, tropical savanna, vegetation dynamics |
| ISSN | 0167-4366 (Print), 1572-9680 (Online) |
