International Journal of Environment and Geoinformatics

153-162

Authors: Mithwa Acharya, Shital .H. Shukla, Manik H. Kalubarme

Remote sensing (RS) and Geographic Information System (GIS) has played a major role in the study of different types of drought i.e. agricultural or hydrological drought. The present study on agricultural Drought assessment was carried out in the Patan District of North Gujarat, India. This study focuses on the assessment of climate change and its impact on Agriculture using Remote Sensing (RS) and GIS technology. The Landsat-7 TM and Landsat-8 OLI data of February-2002 and February-2018 covering Patan District was analysed for Land use/Land Cover mapping and monitoring changes in agricultural area over the period of 16-years. The Spectral vegetation index namely Normalized Difference Vegetation Index (NDVI) was computed using Landsat-7 TM and Landsat-8 OLI digital data for assessment of changes in agricultural vegetation during the drought and normal monsoon periods. Meteorological data like Minimum & maximum Temperatures and rainfall was collected from State Data Centre. Various Drought indices like Standardized Precipitation Index (SPI), Potential Evapo-Transpiration (PET) and Aridity Index (AI) were computed using meteorological data of past 16-years. The results indicate that total agricultural vegetation during drought season was only 21.9 per cent (2002) which has increased to 58.7 per cent during the normal monsoon season of 2018. The rainfall deviations were computed for various years and it was observed that high negative rainfall deviations (-40 to -70%) having low rainfall occurrence were associated with negative SPI values ranging from -0.5 to -1.1 in Patan district. These positive rainfall deviations were associated with positive SPI values of 1.08, 0.57 and 0.62 of respective years indicating moderately wet and mildly wet conditions. During drought year of 2002 total precipitation was very less resulting in Aridity Index of 0.09 which is classified as hyper arid for the Patan District.

172-185

Authors: Shalini Negi , Ankit Arya , Jaydipsinh C. Kathota , Ajay N. Patel2 , Vijay Singh , J. K. Garg1 and Manik H Kalubarme

The present study was carried out in Mahi Canal Command area in Vadodara district for monitoring the environmental impact of water logging and salinity on agriculture using Multi-temporal Remote Sensing data of past 15-years. The Indian Remote Sensing Satellite (Resourcesat-1) LISS-III, LISS-IV and Landsat TM data of 2000, 2006, 2010 and 2016 covering study area was analyzed for mapping waterlogged and salt-affected areas. The data from open-well observations was also collected to monitor the impact of canal irrigation on water-table and in turn on water-logging in the study area. The point measurements of open-well data were used to generate spatial distribution maps using Inverse Distance Weighting (IDW) Interpolation technique and these were superimposed on Satellite data. The waterlogged and salt-affected areas delineated using Remote sensing data was validated by carrying out detailed field survey as well as spatial IDW layers of water-table in the study area. The results of analysis of agricultural area indicate that agricultural area has substantially increased due to introduction of canal irrigation which has helped to improve socio-economic condition of the farmers in the Vaghodia taluka. Agricultural area of medium and dense categories has increased during 2000 to 2016 accounting an increase from 12% to 26% in case of medium and 6.9% to 20% in dense agriculture, respectively. The water table in some of the villages in the study area has slightly come up during the period of last 15-years and at most predominantly after introduction of canal irrigation but it is much below to cause any water logging problem. However, it was also observed that waterlogged and salt-affected areas have decreased over the period of one decade due to augmentation of drainage system in the study area.

192-205

Authors: Hakan Kaya , T. Ahmet Ertek, Cem Gazioğlu

Terkos Lake Formed by the invasion of sea water, the ancient average area calculated as geomorphological is 25 km2. Although the area covered by the lake changes in certain ratios, it has been subject to dramatic changes over time depending on the region. It can be defined as being the most important water basin of Istanbul, and it is an area where scientific work has not been carried out despite all its natural and special beauties. Whereas, being one of the basins of Istanbul, it has been observed that the works carried out at the technical level were carried out by DSİ and İSKİ. The surface area of the lake is 41 km2 and a total drainage area of 775 km2, is approximately 12 km in length and 5 km in width. It is obvious that the morphological features of the lake area, which is located at the border of the most complex and impressive morphological structures. For this purpose, morphometric studies are carried out on the streams feeding the lake and the findings of some shells in the lake and Black Sea are shared in this study.

213-224

Authors: Deniz Aydın , Murat Selçuk SOLMAZ

Oil pollution from ships is an important source of marine pollution and becomes an important problem all over the world. For this reason, every effort should be made to prevent oil spills and to remove them effectively as soon as pollution has emerged. In this respect, various computer simulations are used to get well informed about the fate of spilled oil on the seawater. In this study, the grounding accident of ship M/V Lady Tuna causing 75 tons of fuel spills into the sea on December 18, 2016, close to the coast of Çesme in Turkey, was investigated. The aim of the study is to investigate the oil spill accident and evaluate the response operation of M/V Lady Tuna. To achieve this aim, firstly the reports related to the accident were examined and the response operation was evaluated by modelling of the M/V Lady Tuna accident with PISCES II (Potential Incident Simulation, Control and Evaluation System) simulator. Within this scope, two scenarios were prepared by using PISCES II. The first scenario was created without any response resources to observe the movement direction of the oil slick after the accident. The second scenario was reconstructed with the possible response resources after the oil spill. Through simulation, it was possible to obtain the oil spill/pollution statistics; such as the recovered oil rate, the amount of stranded oil to the coast, the amount of floating oil rate, and other oil spill parameters. As a result, it was evaluated that the oil pollution in the M/V Lady Tuna accident could be responded more effectively and the pollution could be much less. It is assessed that the study will contribute to organizations involved in oil spill response operations.