Investigation of algae distribution in Eymir Lake using site measurements and remotely sensed data

Elahdab, Tarek
The aim of this study is to determine the distribution of Chla in Eymir Lake using remotely sensed data and in-situ data. The study was carried out in three phases; the first phase was taking ground real data from the lake for a 6-month period, secondly the remotely sensed satellite image was taken and analyzed, thirdly a correlation was obtained between the ground data and satellite image, and lastly mapping of the Chla in the lake was made. During the study also the change of the lake during the 6-month period was monitored. The results showed a great variation in the concentration of Chla in the period measured from spring till early fall, from very low almost undetectable concentrations to noticeably very high values especially during summer. The secchi disc depth values ranged from about 3 meters in early spring, to as low as 15 centimeters in late summer; this made it very much related to Chla values. Chla concentrations had a high relationship with the following parameters: DO, TSS, Depth and secchi disc. As for the remotely sensed data also an acceptable level of correlation was obtained between them and Chla data both from laboratory results and in-situ probe.


Application of genetic algorithms to calibration and verification of QUAL2E
Göktaş, Recep Kaya; Aksoy, Ayşegül; Department of Environmental Engineering (2004)
The objective of this study is to develop a calibration and verification tool for the QUAL2E Model by using Genetic Algorithms. In the developed optimization model, an objective function that is formulated on the basis of the sum-of-least squares approach aiming at minimizing the difference between the observed and simulated quantities was used. In order to perform simultaneous calibration and verification, verification of the calibrated results was treated as a constraint and inserted into the objective fu...
Performance evaluation of satellite- and model-based precipitation products over varying climate and complex topography
Amjad, Muhammad; Yılmaz, Mustafa Tuğrul; Yücel, İsmail; Yılmaz, Koray Kamil (Elsevier BV, 2020-05-01)
Accuracy assessment of precipitation retrievals is a pre-requisite for many hydrological studies as it helps to understand the source and the magnitude of the uncertainty in hydrological response variables, particularly over regions with complex topography. This study evaluates GPM IMERGv05, TMPA 3B42V7, ERA-Interim, and ERA5 precipitation products using 256 ground-based gauge stations between 2014 and 2018 over Turkey known to have complex topography and varying climate. Error statistics, categorical perfo...
Assessment of temporal variation and sources of PCBs in the sediments of Mediterranean Sea, Mersin Bay, Turkey
Gedik, Kadir; İmamoğlu, İpek (Elsevier BV, 2011-01-01)
Information on temporal distribution of polychlorinated biphenyls (PCBs) in the coastal sediments of Mediterranean Sea, Mersin was compiled using data published between 1980 and 2009, and the present study. The first congener specific PCB results from the region yield concentration levels of Sigma(41) PCBs in sediments ranging from 0.61 to 1.04 ng g(-1). Sediment profiles show penta-, hexa- and hepta-chlorobiphenyls, specifically, #149 and 153 as the most abundant congeners in all samples. Comparison of tot...
Predicting Diel, Diurnal and Nocturnal Dynamics of Dissolved Oxygen and Chlorophyll-a Using Regression Models and Neural Networks
Human-induced and natural interruptions with continuous streams of observational data necessitate the development of gap-filling and prediction strategies towards better understanding, monitoring and management of aquatic systems. This study quantified the efficacy of multiple non-linear regression (MNLR) versus artificial neural network (ANN) models as well as the temporal partitioning of diurnal versus nocturnal data for the predictions of chlorophyll-a (chl-a) and dissolved oxygen (DO) dynamics. The temp...
Evaluation of a satellite-based global flood monitoring system
Yılmaz, Koray Kamil; Tian, Yudong; Hong, Yang; Pierce, Harold F. (2010-01-01)
This study provides an initial evaluation of a global flood monitoring system (GFMS) using satellite-based precipitation and readily available geospatial datasets. The GFMS developed by our group uses a relatively simple hydrologic model, based on the run-off curve number method, to transform precipitation into run-off. A grid-to-grid routing scheme moves run-off downstream. Precipitation estimates are from the TRMM Multi-satellite Precipitation Analysis (TMPA). We first evaluated the TMPA algorithm using a...
Citation Formats
T. Elahdab, “Investigation of algae distribution in Eymir Lake using site measurements and remotely sensed data,” M.S. - Master of Science, Middle East Technical University, 2006.