Ecological degradation and non-carcinogenic health risks of potential toxic elements: a GIS-based spatial analysis for Doganci Dam (Turkey).

This study was carried out to determine the ecological degradation and non-carcinogenic health risks at Doganci Dam, Bursa, Turkey. Potentially toxic element (PTE) concentrations (ppm) were as follows: Fe (55.030) > Al (27.220) > Mn (1053) > Cr (181) > Ni (180) > Zn (95) > Cu (62) > As (17) > Pb (11) > Cd (0.20) > Hg (0.108). As, Pb, Cd, and Hg were enriched anthropogenically, while other PTEs were of natural origin. The contamination severity index (CSI) indicated a moderate PTE contamination in the dam, mostly due to lithogenic effects. According to the modified hazard quotient (mHQ), ecological risk was identified at the level of extreme severity for Ni of lithological origin, of high severity for Cr of considerable severity for As of anthropogenic origin, and of moderate severity for Cu. According to the ecological contamination index (ECI), the dam had an ecological risk of a slight-to-moderate contamination. Health risk index showed no non-carcinogenic health risks in the dam. Mining, highways, and agricultural activities were identified as the primary anthropogenic drivers to be monitored. The ongoing anthropogenic activities in the Nilüfer Stream basin and natural factors affect the ecological degradation and non-carcinogenic health risk level of the dam.

Spatial distribution, environmental risk assessment, and source identification of potentially toxic metals in Atikhisar dam, Turkey.

The objective of this study was to determine the ecological risk created by metal contents of the surface sediments of Atikhisar dam, Çanakkale, NW Turkey. Enrichment factor (EF) and geoaccumulation index (Igeo) were calculated to determine anthropogenic effects. Ecological risk was assessed using the modified potential ecological risk index (mPER), with its levels being evaluated using the modified ecological risk index (mER). Toxic effects were determined using the toxic risk index (TRI). The ecological risk indices were mapped to provide their spatial distributions. Our findings indicate that enrichment was very high for Hg and significant for Pb, Tl, Cd, and As. The following mER pattern was detected: Hg > Cd > TI > As > Pb > Ni > Cr > Co > Zn > Mn > V. Hg and Cd exhibited extremely high and very high ecological risks, respectively, while TI and As had a significant ecological risk, with Pb exerting a medium ecological risk. Hg, Pb, Tl, Cd, As, Cr, Ni, Zn, and Cu were enriched via anthropogenic effects exceeding their natural concentration levels. Due to their high toxic effects, Hg, Cd, Tl, As, and Pb were identified as the very high risk elements. Mining, household wastes, agriculture, and natural mineral deposits were identified as the possible sources of the potential ecological risk.

Impacts of anthropogenic factors on land degradation during the anthropocene in Turkey.

The aim of the present study was to determine the factors that effected the beginning of the Anthropogenic Era (human age) in Turkey and formation of biomes. Destruction of vegetation, soil erosion and land degradation are the most important factors in the formation of anthropogenic biomes in Turkey. For this reason, first of all, a literature review about land degradation, which has been going on for past 300 years in Turkey, and about its causes was made. Changes that have occurred over the last 70 years were studied with the help of aerial photos and satellite images. In addition, studies we have conducted in the last 35 years have contributed substantially to the determination of the extent of the destruction of vegetation and land degradation in Turkey. As a result of research based on literature reviews and fieldwork, the impact of humans on the natural habitat were identified, and the current situation was studied. The findings about the current situation that emerged due to human impact were then transferred to an electronic environment, and a map of anthropogenic biomes was produced with the help of ArcGIS Desktop software. Based on the results obtained, one can say that the natural habitat has considerably changed over the last 200 years; vegetation has been damaged, and land degradation has become faster because of human activities. These results indicate that 97% of natural biomes have become anthropogenic biomes, and this change has become more obvious during 20h century in Turkey. The results also show that the change has been more influential after 1950.

Land use and land cover change detection in Karinca river catchment (NW Turkey) using GIS and RS techniques.

The basin of Karinca river, in the north-west of Turkey, covers an area of 29,840 ha. Pronounced changes in land use emerged as a result of the development of activities in the tourism sector in Turkey in the 1970's. The basin has been significantly affected in the course of this process. This study was conducted in order to determine the land use changes (as well as the type of changes and their direction) occurring in the use of land in the Karinca river catchment for the period 1979-2007. The geographical data were gathered by using 1:25000 scale topographical maps as a basis. Thus, the existing soil and land use data from 1979 were processed on these bases and the the main materials rendering the land use were produced. Geometric verification was made by putting the previously prepared bases onto landsat ETM+ and satellite images of 2007. In the final stage, results pertaining to the changes in land use were obtained by overlapping the two sets of data. All processes were done using the ArcGIS Desktop v9.x program. According to the data of the year 1979, the catchment area consisted of 43.4% forest, 26.5% grassland, 18.3% olive groves, 10.6% agriculture and 1.2% built-up lands. Comparing these coverage with the data of 2007, show a clear shift among residential areas, olive groves and forest terrain. It was found that the agricultural areas, particularly along the shoreline, were converted into resort houses and that the olive groves (the dominant land use) shifted from lower regions to its upper sectors. All these changes caused loss of natural habitats leading to degradation.