Data inventory and Analysis for the application of WASP in a coastal lagoon

The main objectives of the study were to apply a water quality model to a complex coastal lagoon system, to evaluate its effectiveness, and to prepare guidelines for future water quality modeling studies in such complex systems as well as emphasizing the difficulties faced in developing countries in regard to data availability. Köyceǧiz - Dalyan Lagoon was selected as the study area that is located at the southwest of Turkey along the Mediterranean Sea Coast. Water Quality Analysis Simulation Program version 7 (WASP7) eutrophication module (WASP/EUTRO) was determined to be the most appropriate model for the area of concern. The lagoon system is divided into 49 longitudinal segments, since horizontal and vertical salinity gradients exist in the system, each longitudinal segment is divided into two as upper and bottom segments; therefore, 98 segments represent the lagoon system. During the water quality modeling study, 4 sets of simulations were conducted sequentially starting from the simplest complexity level to higher complexity levels in order to better understand the processes and mechanisms that occur in the system. NH ₃-N, NO ₃ ^--N, Organic N, Detrital N, PO ₄ ³-P, Organic P, Detrital P, dissolved oxygen, CBOD, detrital carbon, salinity and phytoplankton were simulated in the study. The approaches taken here could help as a guide and example for other developing countries that aim to conduct water quality modeling studies. The study should encourage researchers to initiate similar modeling studies of other lagoons in the world, where lack of data is considered to be a major handicap.