Implications of mangrove dynamics for private land use in Bragança, North Brazil: a case study

LARA, RUBÉN JOSÉ; SZLAFSZTEIN, C.F.; COHEN, MARCELO; BERGER, UTA; GLASER, MARION

JOURNAL OF COASTAL CONSERVATION

Springer

Lugar: Amsterdam; Año: 2002 p. 97 - 102

1400-0350

<!-- /* Font Definitions */ @font-face {font-family:Times; panose-1:2 2 6 3 5 4 5 2 3 4; mso-font-charset:0; mso-generic-font-family:roman; mso-font-format:other; mso-font-pitch:variable; mso-font-signature:3 0 0 0 1 0;} /* Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-parent:""; margin:0pt; margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:12.0pt; mso-bidi-font-size:10.0pt; font-family:Times; mso-fareast-font-family:Times; mso-bidi-font-family:"Times New Roman"; mso-fareast-language:PT-BR;} p.MsoBodyTextIndent3, li.MsoBodyTextIndent3, div.MsoBodyTextIndent3 {margin:0pt; margin-bottom:.0001pt; text-align:justify; text-indent:19.85pt; line-height:200%; mso-pagination:widow-orphan; font-size:12.0pt; mso-bidi-font-size:10.0pt; font-family:Times; mso-fareast-font-family:Times; mso-bidi-font-family:"Times New Roman"; mso-fareast-language:PT-BR;} @page Section1 {size:612.0pt 792.0pt; margin:72.0pt 90.0pt 72.0pt 90.0pt; mso-header-margin:36.0pt; mso-footer-margin:36.0pt; mso-paper-source:0;} div.Section1 {page:Section1;} --> This work analyses effects of recent variations of the tidal inundation frequency in a mangrove ecosystem in the Bragança peninsula, North Brazil, and its consequences on land occupation and use. Field data, time series of remote sensing images and local legislation were analyzed focusing on the potential socio-economic impact of a changing environmental setting due to a rise in relative sea level. In the investigated period (1972-1997), vegetation changes along the coastline indicate net losses of mangrove coverage. In the central part of the peninsula, a topographically higher herbaceous plain constituting part of a farm presents an active progression of mangrove forest into an area previously dominated by grasses and herbs. This area consisted of 8.8 km2 in 1972 and gradually decreased to 5.6 km2 in 1997, being progressively replaced by a monospecific stand of the black mangrove, Avicennia germinans. A linear extrapolation indicates that the elevated plain may be completely covered by mangrove in 2035. Current Brazilian legislation prohibits the extraction of mangrove trees without an officially approved management plan. Thus, the usable area of the farm has suffered a reduction of ~40% over 25 years and we predict it could be entirely replaced by mangroves in the next 35 years. In this case study, legislation and ecosystem characteristics are analyzed and a management plan discussed which could represent income alternatives for affected resource users at the local and regional level.