Soil Seedbank Analysis of Wetlands found on Sapelo Island
Abstract
Soil seed bank refers to the naturally stored viable seeds that have potential to regenerate and restore ecological communities following natural or anthropogenic disturbances. Seed banks can provide a “memory” of past vegetation while also giving an indication of the likely structure of future communities. There is barely any literature on what factors control soil seed banks of barrier islands and their sensitivity to sea level rise. The goal of this project is to assess the density of seed banks in various wetlands on an island off the coast of Georgia, in the United States, to determine if the soil seed bank is affected by site-specific characteristics. The hypothesis is that seed bank density will be significantly influenced by wetland salinity level as well as the duration and frequency of inundations. Eighty soil samples were collected from eight wetlands using hand augers in March 2018. Soil samples were air dried and sent to a soil analysis lab to analyze their chemical (total nitrogen, potassium, magnesium, pH, cation exchange capacity, and salinity) characteristics. Soil samples are also being analyzed for texture. Beginning in May 2018, soil samples were set up in germination trays in the greenhouse at Georgia College to assess seed density using the seedling emergence method. As seedlings emerged, they were recorded and removed from trays. Statistical analyses (One-way ANOVA) were used to assess whether seed density differs between wetlands and whether such differences are correlated with wetland characteristics. Preliminary results show that soils with high salinity, high clay content, and frequent or prolonged seawater inundation have the lowest seed density. Preliminary results indicate greater richness in the freshwater samples, with lowest salinity levels. These observations suggest that increased global temperature and the expected rise in seas level will negatively impact seedbank potential of barrier islands and coastal environments.
Soil Seedbank Analysis of Wetlands found on Sapelo Island
Soil seed bank refers to the naturally stored viable seeds that have potential to regenerate and restore ecological communities following natural or anthropogenic disturbances. Seed banks can provide a “memory” of past vegetation while also giving an indication of the likely structure of future communities. There is barely any literature on what factors control soil seed banks of barrier islands and their sensitivity to sea level rise. The goal of this project is to assess the density of seed banks in various wetlands on an island off the coast of Georgia, in the United States, to determine if the soil seed bank is affected by site-specific characteristics. The hypothesis is that seed bank density will be significantly influenced by wetland salinity level as well as the duration and frequency of inundations. Eighty soil samples were collected from eight wetlands using hand augers in March 2018. Soil samples were air dried and sent to a soil analysis lab to analyze their chemical (total nitrogen, potassium, magnesium, pH, cation exchange capacity, and salinity) characteristics. Soil samples are also being analyzed for texture. Beginning in May 2018, soil samples were set up in germination trays in the greenhouse at Georgia College to assess seed density using the seedling emergence method. As seedlings emerged, they were recorded and removed from trays. Statistical analyses (One-way ANOVA) were used to assess whether seed density differs between wetlands and whether such differences are correlated with wetland characteristics. Preliminary results show that soils with high salinity, high clay content, and frequent or prolonged seawater inundation have the lowest seed density. Preliminary results indicate greater richness in the freshwater samples, with lowest salinity levels. These observations suggest that increased global temperature and the expected rise in seas level will negatively impact seedbank potential of barrier islands and coastal environments.