This study aims to clarify the ecological impact of human activity in the miombo woodland of northern Zambia by applying remote sensing. In this study, one of Vegetation Index, NDVI (Normalized Difference Vegetation Index) was applied to make Tree Viability Map. In process, correlation was analyzed between NDVI and wood biomass on 12 plots (50 m × 50 m) identified by GPS. They were positively correlated with significance as r
2 = 0.933.
The image was classified for 4 zones by using three categorized fallow periods of citemene shifting cultivation as border value; minimum fallow period, optimum fallow period and ecological fallow period. Minimum fallow period is one of the shortest term which is enable to produce staple food ( finger millet ), but cause environmental degradation. Optimum fallow period makes possible to achieve sustainable utilization of woodland. Ecological fallow period is the term which has been necessary to recover fully.
The image and ground survey show feature of the land use. There are maize farms within 1 km and degraded woodland within 2 km from the villages. In area of2-8 km, the degraded woodland is reducing with the distance from village, and woodland where optimum fallow period is satisfied is increasing. Mature woodland exists in area of more than 8 km.
In order to continue sustainable utilization, the Bemba have been making use of woodland sparsely and widely. By moving villages and building seasonal dwellings, they have avoided to destroy woodland intensively.
From middle of 1980s, semi- permanent cultivation of hybrid-maize has been introduced with fertilizer. The number of householders who built seasonal dwellings has been reducing, because they harvest maize near villages and lop trees for citemene simultaneously. Moreover, resettlement scheme was established near the village and restrict utilization of local people. The feature of citemene, utilizing woodland sparsely and widely, has been obstructed by introduction of semi- permanent cultivation and socio-economical conditions.
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