Remote sensing and GIS application in the detection of environmental degradation indicators

Abstract

The main aim of this research is to highlight the environment change indicators during the last 20 years in a representative area of the southern part of Iraq (Basrah Province was taken as a case) to understand the main causes which led to widespread environment degradation phenomena using a 1:250000 mapping scale. Remote sensing and GIS's software were used to classify Landsat TM in 1990 and Landsat ETM+ in 2003 imagery into five land use and land cover (LULC) classes: vegetation land, sand land, urban area, unused land, and water bodies. Supervised classification and Normalized Difference Vegetation Index (NDVI), Normalized Difference Build-up Index (NDBI), Normalized Difference Water Index (NDWI), Normalized Difference Salinity Index (NDSI), and Topsoil Grain Size Index (GSI) were adopted in this research and used respectively to retrieve its class boundary. The results showed a clear deterioration in vegetative cover (514.9 km2) and an increase of sand dune accumulations (438.6 km2), accounting for 10.1, and 10.6 percent, respectively, of the total study area. In addition, a decrease in the water bodies' area was detected (228.9 km2). Sand area accumulations had increased in the total study area, with an annual increasing expansion rate of (33.7 km2 · yr-1) during the thirteen years covered by the study. It is therefore imperative that Iraqi government undertake a series of prudent actions now that will enable to be in the best possible position when the current environmental crisis ultimately passes. © 2011 Wuhan University and Springer-Verlag Berlin Heidelberg.