Assessment of the biological values of different land cover types in ...

2) BOTANICAL SURVEYS
2.1 Introduction
The botanical surveys were conducted in the landscapes of Misalai, Shambangeda and Kwatango villages.
These areas have not been studied in-depth previously for their biodiversity value. Most surveys have
concentrated on the Central Government Catchment Forest Reserves and the Nature Reserves, including
intensive biodiversity surveys carried out by Frontier-Tanzania in the 1990s. The aim of the botanical surveys
we conducted was to assess the botanical values of different land cover types in terms of plant resources
which are important for supporting people‟s livelihoods and species which are valuable for biodiversity
conservation.
2.2 Methods
Twelve 10x200 m vegetation plots were established in the village landscapes of Misalai (four plots),
Shambangeda (three plots) and Kwatango (five plots). Within these plots, 1x40 m sub-plots were established
for saplings with dbh less than 10 cm, 5x40 m for trees with dbh greater than 10 cm but smaller than 30 cm
and 10x200 m for trees with dbh greater than 30 cm. Species identification was done for each individual plant,
including trees, saplings, herbs, shrubs and climbers. Also the dbh and height of the plants were recorded.
Specimens difficult to identify in the field were collected for further identification in the herbarium.
Out of the twelve vegetation plots established in different land cover types (see appendix 6), three were
located within the village forest reserves of Misalai, Shambangeda and Kwatango (one in each village forest
reserve); three were within agroforestry sites and two within fallow lands (table 1). In addition, one plot was
established in a mosaic of different land cover types, including fallow land, agroforest and monoculture, and
another one in a mosaic of monoculture and mixed farming. The remaining two plots were established in an
area of mixed farming and within a teak plantation.
Table 1. Frequency of vegetation plots in different land cover types.
Land Cover Type Number of plots
Forest (within village forest reserves) 3
Agroforestry 3
Fallow land 2
Mosaic of fallow land, agroforestry, mixed farming and/or monoculture 2
Mixed farming 1
Teak plantation 1
Habitat details were recorded at each vegetation plot. These included details of topography, altitude, canopy
height, shrub layer, ground layer, aspect, signs of past use and any other feature of interest.
In this study, a herb is defined as any seed-bearing plant which does not have a woody stem. A shrub is
defined as a woody plant with a dbh of less than 10 (excluding tree saplings), which may be accompanied with
several mainstems arising at or near the ground.
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