Environmental Management

, Volume 27, Issue 5, pp 763–776

Mapping Disturbances in a Mangrove Forest Using Multi-Date Landsat TM Imagery

  • JOHN M. KOVACS
  • JINFEI WANG
  • MANUEL BLANCO-CORREA

DOI: 10.1007/s002670010186

Cite this article as:
KOVACS, J., WANG, J. & BLANCO-CORREA, M. Environmental Management (2001) 27: 763. doi:10.1007/s002670010186

Abstract

To evaluate the accounts of local fishermen, Landsat TM images (1986, 1993, 1999) were examined to assess potential losses in the mangrove forests of the Teacapán–Agua Brava lagoon system, Mexico. A binary change mask derived from image differencing of a band 4/3 ratio was employed to calculate any changes within this forested wetland. The results indicate that by 1986 approximately 18% (or 86 km2) of the mangrove area under study was either dead or in poor condition. The majority of this damage had occurred in the eastern section of the Agua Brava basin, which coincides, with the reports of the elderly fishermen. Examination of aerial photographs from 1970 revealed no adverse impacts in this area and would suggest, as postulated by the fishermen and other scientists, that modifications in environmental conditions following the opening of a canal, Cuautlá canal, in 1972 may have initiated the large-scale mortality. Although these areas of impact are still developing, the results from the satellite data indicate that the majority of the more recent changes are occurring elsewhere in the system. Obvious in the 1999 satellite data, but not so in the 1993, are large areas of mangrove degradation in the northern section of the Teacapán region. In the Agua Brava basin, the more recent transformations are appearing on the western side of the basin. Since long-term records of environmental conditions are absent, it is difficult to determine why these latest changes are occurring or even if the earlier losses were the result of the canal. Potential agents of change that have recently been observed include a hurricane, a second canal, and the uncontrolled expansion of the Cuautlá canal since 1994.

KEY WORDS: Landsat TM; Mangrove; Degradation; Mexican Pacific

Copyright information

© Springer-Verlag New York Inc. 2001

Authors and Affiliations

  • JOHN M. KOVACS
    • 1
  • JINFEI WANG
    • 2
  • MANUEL BLANCO-CORREA
    • 3
  1. 1.Department of Geography, Nipissing University, North Bay, Ontario P1B 8L7, CanadaCA
  2. 2.Department of Geography, University of Western Ontario, London, Ontario N6A 5C2, CanadaCA
  3. 3.Direccion de Investigacion Cientifica, Universidad Autónoma de Nayarit, 63190 Tepic Nayarit, MexicoMX