INFLUENCE OF SOIL AND WATER PHYSICO-CHEMICAL PROPERTIES ON VEGETATION STRUCTURE OF ARTIFICIAL PONDS ESTABLISHED WITHIN BAMBOO PLANTATIONS

The distribution of aquatic plants in artificially established aquatic ponds was studied. Four ponds were selected based on variations in water and soil composition, and, vegetation type. A soil and water analysis of these ponds were carried out for the determination of macro-nutrients (Na+, K+, Ca+), pH, ECe and soil texture. Relative density, relative frequency, relative cover and importance value was recorded for the vegetation growing in these aquatic ponds. The results regarding plants association with different levels of salinity showed significant relationships between soil, water and plant species. Phragmites karka (Pk), Phalaris minor (Pm), Cynodon dactylon (Cd), Cyperus rotundus (Cr), Cenchrus ciliaris (Cc), Sonchus arvensis (Sa), Phyla nodiflora (Pn) and Fumaria indica (Fi) were found on relatively higher salinity levels (Na, ECe and pH) and low potassium and calcium content. Typha domingensis (Ty), Tamarix dioica (Td), Azolla pinnata (Az), Eclipta alba (Ea) and Imperata cylindrica (Ic) were recorded in ponds with slightly higher ionic content and low salinities (ECe=1.8 dS m(-1)) indicating these species can tolerate both low salinity and pH. Species growing in other ponds did not show any significant link to soil or water physico-chemical properties. It was concluded that the distribution of plant species was significantly affected by salinity levels (ECe), pH and ionic concentration of aquatic ponds.