Soil characterisation for teak (Tectona grandis) plantations in the Nzara district of Southern Sudan
Date
2008-12
Authors
Journal Title
Journal ISSN
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Publisher
Stellenbosch : Stellenbosch University
Abstract
The characterization of soils in Nzara District of Southern Sudan in comparison to other tropical
teak growing countries (Tectona grandis) – in respect of extensions to existing and/or the
establishment of new teak plantations – were done by firstly considering the soils of three
existing plantations: Yoboa, Mabarizinga and Nagondi, and secondly by considering soils
outside and inside the existing teak plantations in respect of land uses. From these soil
characterizations, it emerged that considerable positive returns can be expected from teak
plantings in the area as an investment, provided that appropriate site management is
implemented.
Climatic data of the Nzara area compared favorably with the climatic range of areas where teak
grows naturally and the world’s dominant producers: mean annual rainfall 1350-1600 mm with a
distribution over 6-8 months compares well with that of Myanmar (1250-3750 mm) and
Indonesia (1511-2108 mm) both with at least 3 months of dry season. The mean annual
temperature of 28-350C compares well with 15-410C and 30-320C of Myanmar and Indonesia
respectively.
The Yoboa and Mabarizinga sites should be prioritized as they appear slightly more suitable than
the Nagondi site. All three sites have a dominant soil texture of Sandy Clay Loam similar to
Sandy Loam of most areas of other tropical countries where teak is growing well (such as India,
Indonesia and Nigeria). Yoboa and Mabarizinga however distinguish themselves by having the
highest soil pHwater values range from 6.4±0.56 and 6.04±0.7 in top soils; 5.91±0.5 and
5.46±0.61 in subsoils at Yoboa and Mabarizinga respectively; the highest soil organic matter
content 1.8±0.34% and 1.92±0.43% in topsoil 0.89±0.16% and 1.13±0.19% in subsoils; as well
as the highest P content in both available (0.09±0.04% and 0.03±0.04% for topsoils) and total
forms (1.19±0.26% and 0.9±0.3% also on topsoils). These values though very low in absolute
terms, are not much different from those of other tropical teak-growing countries. Management
strategies intended to preserve and improve the present status, particularly the protection of top
soil horizons against mainly water erosion, would be able to boost the site productivity.
Description
Thesis (MScFor (Forest and Wood Science))--Stellenbosch University, 2008.
Keywords
Teak -- Southern Sudan, Soils, Erosion, Dissertations -- Forest and wood science, Theses -- Forest and wood science