Mgambo Forest Reserve: A biodiversity survey. - Eastern Arc ...

Mgambo Forest Reserve
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4.0 VEGETATION
Authors: Oliver, S.A., Ntemi, A.S., Bracebridge, C.E. pp. 11-42
4.1 Introduction
A species inventory was compiled of the trees and shrubs found within the Mgambo Forest
Reserve (FR). Simple, quantitative and repeatable methods were employed and the results are
comparable with other forest surveys undertaken by FT FRP. Human disturbance within the forest
was also documented. Botanical and disturbance data collected by this survey have been entered
onto the EUCAMP database.
Figure 4 Typical Miombo woodland (Brachystegia sp.) in Mgambo FR
4.2 Methods
The forest reserve was divided into a grid of numbered squares marked in the field by tagged
transect lines. All methods are based on this grid system and are detailed in the FT FRP
methodologies report (SEE, 1998). A brief description is presented below. The location of
vegetation plots and disturbance transects were recorded using Global Positioning System (GPS)
(see Appendix 2) and their locations on the Mgambo FR outline are illustrated in Figure 5.
4.2.1 Forest composition
Three methods were used to analyse forest composition: (1) quantitative vegetation analysis; (2)
opportunistic observations and (3) disturbance transects.
4.2.1.1 Quantitative vegetation analysis
The botanical survey was based on a 900m x 450m grid marked in the field using tagged transect
lines. One plot 50m x 20m was sampled in each grid square, giving an approximate sampling
intensity of 0.25%. The 50m x 20m vegetation plots were located in the southeast corner of each
of the 900m x 450m grid rectangles. Within each sample (vegetation) plot, every tree with a
diameter at breast height (dbh) of 10cm and over was recorded, marked with red paint, and
identified. An EUCAMP botanist provided the field identification of plant species. Specimen
collection was made of fertile individuals, and difficult to identify species.
East Usambara Conservation Area Management Programme Technical Paper 59