Impact of small scale tobacco growing on the spatial and temporal distribution of Miombo woodlands in western Tanzania

Pius Z. Yanda

Institute of Resource Assessment, University of Dar Es Salaam, P.O. Box 35097, Dar es Salaam, Tanzania. E-mail: yanda@ira.udsm.ac.tz. Tel: +255-22-2410144.

Fax: +255-22-2410393.

Accepted 15 December, 2009

   Abstract

This paper examines the impact of tobacco farming on Miombo ecosystem in Western Tanzania. Methods employed include literature review, secondary data collection, data sets generation from satellite images (1984, 1995 and 2000) and fieldwork for ground verification. Data sets on tobacco production were computed to generate hectarage cleared for tobacco farming and tree felling for tobacco curing. Trend of tobacco production over time was determined. Findings demonstrate that between 1975 and 1989 production of tobacco was fluctuating. Hence the size of land cleared shows low correlation (R² = 0.19) with time (years).  From 1990 to 1996 tobacco production and the size of cleared land for tobacco farming and curing increased consistently with high correlation coefficiency (R² = 0.76) with time (years). Land converted from natural vegetation to cultivated land between 1984 and 1995 was 4.7% compared to 11.2% that was converted between 1995 and 2000. Also, about 7.8% of the cultivated land in 1984 had been, by 1995, regenerated into woodland. Between 1995 and 2000 regenerated land is only 2.4% of the total cultivated land. Total cleared land for tobacco growing and curing is projected to double by year 2016. From this study, it is evident that much as deforestation is high, there is vegetation regeneration indicating the ability of Miombo vegetation to recover. Macro-policies have contributed to the land use changes, and consequently on the Miombo ecosystem.

Key words: Miombo, tobacco farming, ecosystem degradation.