Considering the temporal and spatial dynamics of Laguna Lake, equally important to the conduct of a diurnal wet season survey is a corresponding dry season observation. The dry season is not only expected to provide a more stratified bio-physical condition with an intense summer thermal heating, but also a dynamic bio-chemical aspect with the intrusion of polluted seawater from Pasig River.

A 51-hour continuous intensive survey was conducted to collect hydrodynamic and water quality data to describe the vertical temporal variation of physical, chemical and biological parameters at West Bay, Laguna Lake for the dry season condition. The survey was composed of two parts:

1) Monitoring of data-logging sensors for time-series measurement. Parameters measured are hydrodynamic, water quality and meteorological variables.

2) Water quality sampling and measurement i) Water quality profiling using an std-type instrument (AAQ1183). AAQ measures water quality parameters of temperature, conductivity, salinity, chlorophyll-a, turbidity, pH and dissolved oxygen. ii) Water sampling for analysis of total nitrogen, total phosphorous, dissolved nutrients and chlorophyll-a.

Water quality profiling (AAQ1183) and nutrient sampling were conducted to describe significant variations with the changing physical environment. Sediment oxygen demand measurement around the lake was done as well to acquire relevant information for the development of the water quality model of Laguna Lake.

The intensive survey was conducted at the IMSWES monitoring platform in West Bay Laguna Lake in collaboration with the Laguna Lake Development Authority.

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Continuous 51-hour measurement at the IMSWES monitoring platform.