The ability of aquatic macrophytes to maintain water clarity in two tropical ponds

Abstract

The ability of aquatic macrophytes to maintain water clarity was investigated in two tropical ponds [1999–2001]. Low chlorophyll‐a concentration (0.2–3.5 mg/m³) was observed throughout the study period, which reflected the absence of any algal bloom. At a high coverage (≥ 90%), the ability of Vallisneria spiralis to maintain Secchi disk transparency (> 2 m) extended to the deepest point (3.5–4.4 m) even at high Kjeldahl nitrogen (1.2–29.8 mg/l) and total phosphorus levels (0.2–1.2 mg/l).

Keywords:

• Secchi disk transparency
• Total Kjeldahl nitrogen
• Total phosphorus; Chlorophyll‐a
• Vallisneria spiralis

Acknowledgement

Thanks are due to Mr L. B. Magranti and Mr G. Bhaumik for providing all possible assistance during the fieldwork.