Kibler, K. M., G. Cook, L. G. Chambers, M. Donnelly, T. Hawthorne, F. Rivera, and L. Walters. 2018. Integrating sense of place into ecosystem restoration: a novel approach to achieve synergistic social-ecological impact. Ecology and Society 23(4):25. https://doi.org/10.5751/ES-10542-230425

Hydrodynamic differences among shorelines with no vegetation, reference vegetation (mature mangrove), and vegetation planted on restored shoreline (marsh grass and young mangrove) were compared based on field observations 6.5 years after living shoreline restoration. Mean current velocities and waves were more strongly attenuated in vegetation (from channel to shoreline: 80–98% velocity decrease and 35–36% wave height reduction) than in bare shoreline (36–72% velocity decrease, 7% wave height reduction, ANOVA: p < 0.001). Normalized turbulent kinetic energy dissipation rates were significantly higher in reference vegetation (0.16 ± 0.03 m⁻¹) than in restored (0.08 ± 0.02 m⁻¹) or bare shoreline (0.02 ± 0.01 m⁻¹, p < 0.001). Significant differences in the current attenuation and turbulence dissipation rates for the reference and planted vegetation are attributed to the observed differences in vegetation array and morphology. Although the hydrodynamic analyses did not suggest limitations to recruitment, mangrove seedlings were not observed in restored vegetation, while four recruited seedlings/m were counted in the reference vegetation. The lack of recruitment in the restored shoreline may suggest a lag in morphological habitat suitability (slope, sediment texture, organic matter content) after restoration. Although hydrodynamics suggest that the restored site should be functionally similar to a reference condition, thresholds in habitat suitability may emerge over longer timescales.

To manage flood risk, floodplains are often designated for uses that support flood storage and ecosystem conservation. In such cases, direct human uses of flood-prone land are often restricted. Despite effectiveness at reducing flood risk, the exclusion of direct human uses from flood-prone lands is not always possible. Additionally, where livelihoods are tied to the use of flood-prone land, such strategies may eliminate floodplain-related benefits. To support implementation of Integrated Flood Management suited to such contexts, we propose a framework in which the livelihood benefits of direct floodplain use are distinguished from those supplied through ecosystem services. Decision-makers may apply this approach where flood risk, ecosystem, and livelihood objectives must be balanced. Because flood adaptation strategies may involve risk-benefit trade-offs, we propose the integrated assessment of flood risk and probabilistic benefits to inform decision-making. Through parallel analysis of probabilistic damages and benefits, a broad suite of management actions may be evaluated to minimize flood risk while maximizing river-derived benefits. Application of the proposed framework and risk-benefit analysis may highlight effective solutions that reflect the pressures and opportunities of developing countries. For instance, measures that reduce flood risk by targeting coping capacity and adaptation, as opposed to flood exposure, may be emphasized.

Mangrove-forest sustainability hinges upon propagule recruitment and seedling retention. This study evaluates biophysical limitations to mangrove-seedling persistence by measuring anchoring force of two mangrove species (Rhizophora mangle L. and Avicennia germinans (L.) L.). Anchoring force was measured in 362 seedlings via lateral pull tests administered in mangrove forests of two subtropical estuaries and in laboratory-based experiments. Removal mechanism varied with seedling age: newly established seedlings failed due to root pull-out while seedlings older than 3 months failed by root breakage. The anchoring force of R. mangle seedlings was consistently and significantly greater than A. germinans (p = 0.002); however, force to remove A. germinans seedlings increased with growth at a faster rate (p < 0.001; A. germinans: 0.20–0.23 N/g biomass; R. mangle: 0.04–0.07 N/g biomass). Increasing density of surrounding vegetation had a positive effect (p = 0.04) on anchoring force of both species. Critical velocities at which seedlings become susceptible to instantaneous uprooting estimated from anchoring forces measured in the field were 1.20 m/s and 1.50 m/s, respectively, for R. mangle and A. germinans. As estimated critical velocities exceed typical flow magnitudes observed in field sites, removal of established seedlings likely occurs following erosion of sediments from the seedling base.