Distribution, interspecific associations and abundance of aquatic plants in Lake Bisina, Uganda

A survey of floating-leafed and submersed aquatic plants was conducted in Lake Bisina, Uganda. Seven of the species collected were not previously reported from Lake Bisina, including Stuckenia pectinata (L.) Borner, Utricularia reflexa Oliv., Utricularia foliosa L., Caldesia parnassifolia (L.) Parl., Wiesneria filifolia Hook. f., Brasenia schreberi J. F. Gmel., and a multicelluar algae, Chara sp. Examination of pairwise associations between plant species revealed that the Chara sp. was negatively associated with Najas horrida ex Magn., Nymphaea caerulea Savigny, and Utricularia reflexa Oliv., which was likely due to differences in habitat requirements. A strong, positive association between N. caerulea and U. reflexa may have been due to niche similarities, but may also indicate a commensal relationship with U. reflexa performing well under shaded conditions provided by N. caerula. Hydrilla verticillata was the only species associated with water clarity, with abundance increasing as turbidity increased. This study provides new baseline information on the diversity, distribution, and interspecific associations of floating-leafed and submersed aquatic plants in Lake Bisina, Uganda, that will be useful for comparison with future biological studies.