MATRIX project, Mabira in Uganda

Data on vascular plants was collected in 2009-2011 in Mabira Forest, Uganda as part of the MATRIX project in order to look at forest recovery from disturbance.

Mabira Central Forest Reserve (hereon Mabira Forest) is close to Lake Victoria in Central Uganda. Mabira Forest is a semi-deciduous forest, considered secondary growth and highly influenced by human activities. About 95 per cent of the forest is of the Celtis-Chrysophyllummedium altitude semi-deciduous forest type; within this there are different sub-climax communities which have developed since the forest underwent phases of felling and heavy encroachment. Three ages of stand were surveyed to examine how quickly plants were recovering from disturbance.

Transects of 10 m × 30 m were established in randomly-selected compartments in each of the three types. In order to cover a range of microhabitats, transects were arranged in ‘triplets’ of increasing distance upslope from forest streams, at 5 m, 65 m, and 125 m. For all other angiosperm sampling, transects were situated in the same locations (subject to 10 m GPS-derived relocation error) as the 5m and 125 m transects for the ferns. In total, 63 transects were sampled for ferns and 35 for angiosperms.

In transects where angiosperms were sampled, trees of DBH (diameter at breast height) >10 cm were counted across the whole transect. Ground layer vegetation up to 2 m height was sampled by dividing the 10 × 30 m transect into 5 × 5 m plots and sampling six of those subplots, moving along the transect on alternate sides.

All the species in these subplots were recorded, (including all woody plants large enough to identify and with stems < 10 cm DBH), and their percent cover estimated. Ferns were recorded by abundance of individuals, which was estimated in classes (<5, 6-15, 16-30, 31-50, 50-100, >100). Individuals which could not be identified were taken to Makerere University Herbarium for identification.

We are grateful to the Ugandan National Forest Authority (NFA) for permitting access to work in Mabira.