RECOVER MAP 3.1.3.9 Trophic Level - Primary - Mangrove Forest Soil Accretion|湿地生态数据集|红树林生态数据集

Understanding the factors controlling changes in wetland sediment surface elevation has been identified as a key component of the Comprehensive Everglades Restoration Plan (CERP). This is true for coastal saline wetlands such as mangrove forests and for interior freshwater wetlands such as the ridge and slough. Hydrology is a driving factor for plant species distribution in wetlands and for influencing primary production. Upstream freshwater inflows determine downstream salinity regimes which in turn influence plant species occurrence and productivity. Plant productivity, especially belowground productivity (i.e. roots) can produce peat which has a positive feedback on sediment elevation by raising it (Fig. 1). Disturbances (drought, fires and hurricanes) can influence elevation through a variety of mechanisms. Hurricanes may deposit sediment
leading to a direct increase in wetland elevation. Hurricanes may also kill the vegetation which leads to peat collapse and loss of elevation (Cahoon et al. 2003). Prior to FY2004, the U.S. Geological Survey – Biological Resources Discipline was sampling wetlands hydrology at a number of sites in the coastal Everglades as part of the Mangrove Hydrology Sampling Network (Fig. 2, see Smith 2004). Both surface water and ground water sampling wells were installed along two transects. Sediment elevation and vegetation dynamics were sampled concurrently at these sites. Our work addresses several questions related to wetland sediment surface elevation in the coastal Everglades: (1) Wetland sediment surface elevation is more variable in freshwater than in estuarine wetlands; (2) Fluctuations in groundwater stage are more important in determining sediment surface elevation in downstream estuarine wetlands than are factors in the shallow root zone; (3) Surface water fluctuation is more important in controlling sediment elevation in upstream freshwater wetlands; and, (4) How do pulse disturbances, such as hurricanes, interact with long-term processes, such as
sea-level rise, to affect wetland elevation? With regard to CERP, we address Hypothesis Cluster 9.2.4 of the 2005 Assessment Strategy for the Monitoring and Assessment Plan. Specifically we deal with Hypothesis #4: Sea level and freshwater flow as determinants of production, organic soil
accretion and resilience of coastal mangrove forests (Recover 2005).