Diversity of Vascular Macrophytes in Lake Chahafi in Kisoro District, South-Western Uganda.

Abstract

In freshwater ecosystems, macrophytes are sensitive to water level fluctuations attributed to the varying distance from the shore and physio-geographical parameter including anthropocentric dimensions. However, this study was conducted for quantitative and diversity analyses of aquatic macrophytes of Lake Chahafi which is on an altitude of 1890 m.a.s.l. 114 samples of macrophytes were collected along the 19 laid transects from the shore to the interior of the lake. A total of 32 species of macrophytes were identified and reported. These belonged to 18 families and 32 genera. They varied in different morphological groups which included: emergent, submerged, rooted floating leaf type and free floating macrophyte species. The most abundant species were emergent (20), followed by submerged species (5), free floating species (4) and 3 species of floating-leaved macrophytes. Regression analysis showed the decreasing trend in diversity and richness with increasing distance from the shore while at the same time overall macrophyte biomass increased. The abundant growth of aquatic macrophytes in Lake Chahafi may be due to anthropogenic activities of local people and tourists, for example fishing, water extraction and agriculture. The abundance of the northern part of the lake may be correlated with the huge influx of nutrients from nearby crop lands in the hills due to landslides and erosion causing eutrophication.