Phytoplankton Primary Productivity And Water Quality Of Lake Danao Phytoplankton Primary Productivity And Water Quality Of Lake Danao

Abstract

Primary productivity gives information related to the amount of energy available to support bioactivities of the  system. The present study aimed to know the status of phytoplankton primary activity of Lake Danao in relation to water quality parameters.  Gross primary productivity (GPP) and Net primary productivity (NPP) are determined by the light and dark reactions also known  as  ‘Light and Dark bottle’ method of Lewis (1970). Results indicate that Primary productivity (GPP  and  NPP)  was significantly higher during the dry period than the wet period. The mean of water temperature,  pH  and D.O. did not vary across stations.  Turbidity , TSS, Hardness and alkalinity is higher on  wet period. No change in color  in all stations were  observed. Phosphates did not differ between periods, while nitrate content increases during wet period.  The results are compared to the DENR standards and does not qualify  for  Class A (Public Water Supply II) and  Class B (Recreational Water Class I) intended for primary contact  recreation. It indicates that water bodies is polluted and are influenced by pollution-causing activities.  In order to maintain the lake, coordination and effort is required from the people and government and non- government organizations. It is necessary to rehabilitate the lake as recreational site for sustainability and protection of the lake.