In the 90´s, Ciénaga Grande de Santa Marta (CGSM) mangroves died due to high levels of salinity in soil. This fact stimulated the reopening of five natural channels to reduce salinity and improve the forests' conditions (PROCIENAGA Project). In order to make a historical evaluation of mangrove rehabilitation trajectories, summarize the lessons learned with the rehabilitation project implemented and to simulate future scenarios; this study used a principal components analysis with hierarchical classification to describe the changes of variables over time, its relationship with the abiotic environment (interstitial salinity and temperature -0.5m, flood level), species composition and structure assembly (age composition, Basal Area-AB and the Importance Value Index-IVI) and ecological functionality (DP-Availability of propagules and Growth Rate-TC) in five stations (Rinconada-RIN, Caño Grande-CGE, Aguas Negras-ANE, Kilómetro 22-KM22 and Luna-LUN). Additionally, to simulate future AB trends, an Individual Based Model (FORMAN) was validated, calibrated and adjusted using monitoring data obtained by INVEMAR. The results suggests a robust analysis methodology; recovery trends of the abiotic conditions in CGE, ANE, KM 22 and LUN and convergence of structural attributes of ANE and KM22, when these where compared to RIN, the reference station. LUN and CGE followed different patterns of structural attributes, this shows that restored stations may take longer to recover desired conditions, and perhaps they may never achieve it. On the other hand, active interventions for restoration are strong enough to switch their path. The DP and CT analysis was restricted due to the high variability in the database, although it showed ecosystem functionality maintenance in all stations. The adjustments in salinity and recruitment rates allow us to calibrate the FORMAN model to CGSM patterns. Under an optimistic scenario, the system will reach stability in a long term (> 100 years) and coexistence of the three mangrove species, with a clear A. germinans dominance. Projecting an increase in interstitial salinity, based on the records of the last three years, the system will collapse in a short term (10 years), showing how vulnerable CGSM is to saline increases and its need for effective management actions implementation. This research opens the door for understanding the patterns and dynamics of restored ecosystem in the long term, and provides inputs and technical basis for planning new restoration strategies, management and modeling in an estuarine complex, which also would be applied to other mangrove ecosystems.

Aim  This study determines whether the establishment of tropical protected areas (PAs) has led to a reduction in deforestation within their boundaries or whether deforestation has been displaced to adjacent unprotected areas: a process termed neighbourhood leakage. Location  Sumatra, Indonesia. Methods  We processed and analysed 98 corresponding LANDSAT satellite images with a c. 800 m2 resolution to map deforestation from 1990 to 2000 across 440,000 km2 on the main island of Sumatra and the smaller island of Siberut. We compared deforestation rates across three categories of land: (1) within PAs; (2) in adjacent unprotected land lying with 10 km of PA boundaries; and (3) within the wider unprotected landscape. We used the statistical method of propensity score matching to predict the deforestation that would have been observed had there been no PAs and to control for the generally remote locations in which Sumatran PAs were established. Results  During the period 1990–2000 deforestation rates were found to be lower inside PAs than in adjacent unprotected areas or in the wider landscape. Deforestation rates were also found to be lower in adjacent unprotected areas than in the wider landscape. Main conclusions  Sumatran PAs have lower deforestation rates than unprotected areas. Furthermore, a reduction in deforestation rates inside Sumatran PAs has promoted protection, rather than deforestation, in adjacent unprotected land lying within 10 km of PA boundaries. Despite this positive evaluation, deforestation and logging have not halted within the boundaries of Sumatran PAs. Therefore the long‐term viability of Sumatran forests remains open to question.

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Allometric equations for the estimation of tree volume and aboveground biomass in a tropical humid forest were developed based on direct measurements of 19 individuals of seven tree species in Northern Costa Rica. The volume and the biomass of the stems represented about two-thirds of the total volume and total aboveground biomass, respectively. The average stem volume varied between 4 and 11 Mg/tree and the average total aboveground biomass ranged from 4 to 10 mg/tree. The mean specific gravity of the sampled trees was 0.62 ± 0.06 (g/cm 3 ). The average biomass expansion factor was 1.6 ± 0.2. The best-fit equations for stem and total volume were of logarithmic form, with diameter at breast height (R 2 = 0.66 − 0.81) as an independent variable. The best-fit equations for total aboveground biomass that were based on combinations of diameter at breast height, and total and commercial height as independent variables had R 2 values between 0.77 and 0.87. Models recommended for estimating total aboveground biomass are based on diameter at breast height, because the simplicity of these models is advantageous. This variable is easy to measure accurately in the field and is the most common variable recorded in forest inventories. Two widely used models in literature tend to underestimate aboveground biomass in large trees. In contrast, the models developed in this study accurately estimate the total aboveground biomass in these trees. RESUMENEcuaciones alométricas para la estimación de volumen y biomasa aérea deárboles en un bosque húmedo tropical fueron desarrollados basados en mediciones directas de 19 individuos de siete especies deárboles al norte de Costa Rica. El volumen y la biomasa del tronco representaron cerca de dos terceras partes del volumen total delárbol y de la biomasa aérea total. El volumen promedio del tronco varió entre 4 y 11 Mg/árbol y el promedio de la biomasa aérea total varió entre 4 y 10 mg/árbol. La gravedad específica promedio de losárboles muestreados fué de 0.62 ± 0.06 (g/cm 3 ). El factor de expansión de biomasa promedio fué de 1.6 ± 0.2. Las ecuaciones de mejor ajuste para el volumen de tallo y total fueron de tipo logarítmico, con el diámetro a la altura de pecho (R 2 = 0.66 a 0.81) como variable independiente. Las ecuaciones de mejor ajuste para biomasa aérea total, las cuales fueron basadas en combinaciones de diámetro a la altura de pecho y altura total y comercial como variables independientes, presentaron valores de R 2 entre 0.77 y 0.87. Los modelos recomendados para estimar biomasa aérea total están basados en diámetro a la altura de pecho, porque la simplicidad de estos modelos es ventajosa. Esta variable es de fácil medición en el campo y tiene mayor precision, además, es la más comúnmente registrada en inventarios forestales. Dos modelos ampliamente usados en la literature tienden a subestimar la biomasa aérea total enárboles grandes. En contraste, los modelos desarrollados en este estudio, estiman con mayor precisión la biomasa aérea total de estosárboles.