Change of Land Use Pattern from Shrimp Farming by Using Aerial Photogrammetry in Ranot District Songkhla Province

Abstract

The aim of this study was to investigate the transformation of land use to shrimp farming area in Ranot District, Songkhla Province. The researchers examined the transformation pattern by using precise aerial photogrammetry techniques in conjunction with Geographic Information Systems (GIS). The results showed that the reliability index for the total land area used for shrimp farming in 2002, 2009 and 2015 were 95.83 ± 4.24, 92.71 ± 5.40 and 92.71 ± 5.40 (the range acceptance rate was good.), respectively. In 2002, the total land area used for shrimp farming was 29,572 rai. It can be classified into 99.71% for active shrimp farming and 0.29% for abandoned shrimp ponds. From 2009 to 2015, land use for shrimp farming increased steadily. In 2009, the total shrimp farming land area was 31,761 rai and this rose to 35,712 rai by 2015. However, the analyzed results showed that in 2002 to 2009, most of the shrimp farming area at 1,274 rai changed from abandoned rice fields, followed by community areas and buildings at 575 rai and active rice fields at 164 rai. Correspondingly in 2015, most shrimp farming areas also were changed from abandoned rice fields, followed by active rice fields at 1,090 rai and community areas and buildings at 559 rai. The results also showed that in 2002 to 2015, the land use pattern in Ranot District, Songkhla Province was changed increasingly from rice fields to shrimp farming areas, especially with the transformation of abandoned rice fields. The total land area used for shrimp farming was increased and the abandoned shrimp ponds was decreased around 45% in 2002-2009 and 2009-2015. In addition, abandoned shrimp ponds were not suitable for change into other land use types unless for shrimp farming.