Pesticide accumulations in water and sediment of dam lakes located in Thrace part of Marmara Region (Turkey)

Abstract

Ergene River Basin, which is located in the north-west part of Turkey, is the most significant aquatic habitat of Thrace Region. In addition to the presence of important lentic ecosystems in the basin, there are also important natural and artificial lotic ecosystems, which are of great importance both for the natural life and for the local public. Thrace Region is one of the most important and fertile agricultural regions of our country and despite such a great importance of Ergene River Basin for Thrace Region, almost all the components of the watershed are being exposed to an intensive pollution by means of especially agricultural applications. In this research, the pesticide concentrations in water – sediment of most significant 6 dam lakes (Altinyazi, Karaidemir, Kayalikoy, Kirklareli, Sultankoy and Suloglu Dam Lakes) located in Ergene River Basin were investigated. Water – sediment samples were taken in rainy season (spring) of 2018 from 15 stations and pesticide concentrations (174 pesticides varieties) were determined by using an LC/MS. In addition, the investigated locations were classified in terms of pesticide accumulations in water and sediment by using Cluster Analysis (CA). As a result of this research, 3 pesticide types in water and 18 pesticide types in sediment were detected. Carbendazim and forchlorfenuron-706 were recorded as the most dominant pesticide types for water samples and propiconazole and prochloraz were recorded as the most dominant pesticide types for sediment samples. The total pesticide contents determined in both water and sediment were found to be much higher in Altinyazi and Sultankoy Dam Lakes compared to the other investigated reservoirs. As a result of CA, 3 statistically significant clusters were formed both for water and sediment, which were named as “high contaminated zones”, low contaminated zones and moderate contaminated zones.