Validation and application of an individual based restoration model for three mangrove species in Cienaga Grande de Santa Marta

Authored by Rodriguez-Rodriguez Jenny Alexandra, Mancera-Pineda Jose Ernesto, Rodriguez-P Juan Manuel

Date Published: 2016

DOI: 10.15446/caldasia.v38n2.55360

Sponsors: Corporación Autónoma Regional del Magdalena (COR-PAMAG)

Platforms: Java C

Model Documentation: Other Narrative Mathematical description

Model Code URLs: Model code not found

Abstract

During the 1990s, the mangroves of the Cienaga Grande de Santa Marta (CGSM) experienced a massive die-off due to high levels of soil salinity. In response, five natural channels were reopened to reduce salinity and improve the forests' conditions (PROCIENAGA Project). Based on this experience, in 1999, an Individual Based Model (FORMAN) was developed to simulate forest restoration trajectories; however, this model was restricted to one site in the CGSM and until now it has not been tested. In order to improve its accuracy and predictability in simulations of basal area (BA) trends of the tree species Rhizophora mangle, Avicennia germinans y Laguncularia racemosa we validated, calibrated, and adjusted the FORMAN model using 16 years of monitoring data. We modified the model interface and adjusted calculation routines and parameters. We performed two simulation scenarios: (1) Assuming a stable range of variation in salinity and (2) Increasing salinity based on the average increase over the last three years. The adjustments to the salinity calculation and recruitment rates allowed us to calibrate the model and reproduce both the pattern and magnitude of the observed data in three stations. In two stations we could reproduce only the pattern of the data. The model accurately reproduced general trends in changes in the BA of each species, as well as the current BA for stations that initially suffered greater impact. Under a scenario of stable soil salinity, the system will reach stability in the long term (> 100 years), while a constant increase in interstitial salinity, would result in a major decrease in BA in the short term (< 20 years). These results show the vulnerability of CGSM to increases in salinity and the need to implement sustainable management practices. This study contributes to the understanding of long term dynamics in tropical coastal lagoons and highlights the importance of modeling as a basic tool for rehabilitation and management projects.

Tags

Dynamics growth System Consequences Forest Colombia Salinity Secondary succession Caribbean coast Gulf