Identification of changes mangrove areas toward shoreline changes in East Coast of Surabaya 2004-2017

Abstract

Changes in the mangrove area is the crucial cause for the shoreline changes, it happens since that vegetation stores sediments which lead to accretion and if that vegetation is reduced or damaged, it will cause abrasion. This research aims to identify the changes in the mangrove area and the shoreline of the east coast of Surabaya (Purmabaya) during 2004-2017. This research uses Landsat image 7 ETM + and Landsat image 8 OLI by applying overlay method which is spatial analyzed. During 2004-2017, there was a reduction on mangrove area for 167,701 Ha and the width was increasing for 374,183 Ha. At the same time, there was an abrasion for 12,1 Ha and an accretion for 314,661 Ha. In Kalisari, the widest accretion was 233,833 Ha which was followed by the increasing width of the mangrove area, while in Keputih had the widest abrasion, 6,87 Ha. The conclusion is the changes of the mangrove area Purmabaya keep increasing likewise the shoreline changes, especially the accretion width or the increasing width which keep changing during 13 years (2004-2017).