Remote sensing to assess shrimp farming development in Haiphong ofVietnam

摘要

Remote sensing (RS) was used to detect land use changes in shrimp farming area to examine the status of shrimp farming, and to recommend a management guideline for sustainable shrimp farming development. This study was conducted at Doson and Kienthuy districts of Haiphong in Vietnam during June-December 2002. Three images acquired in 1990, 1995 and 2000 were radiometrically normalized and geometrically registered to a universal transverse mercator (UTM) map projection. Each image was separately classified into different categories of aquaculture ponds, agricultural land, salt farms, village mixed orchards, urban or build-up land, mangroves, rangeland, hill-land forest, and open water. Visual image classification in conjunction with associated topographic maps and related reports was employed on all images. The classified images produced were analyzed for changes in each land use category by overlaying them in a geographical information system (GIS) framework. The results indicated a significant increase of mangrove area from mudflat area and spatial increment of shrimp pond area converted from agricultural land and salt farms. Shrimp pond area increased rapidly from 491 ha in 1990 to 607 ha in 1995 and 1,690 ha in 2000. This study suggests that development of shrimp aquaculture should be done on a regulated basis to minimize environmental degradation and guide shrimp farming development towards sustainable use of coastal resources.