Presentation Information
[O13-P10]Case Studies on the Impacts of Storms and Natural and Nature-Based Features on Water Quality and Ecosystem Resiliency in Southwest Florida, USA
*Sarah Dabees1 (1. Aubrey Rogers High School)
Keywords:
Ecosystem Resiliency,Water Quality,Coastal Sustainability,Natural and Nature-Based Features,Submerged Aquatic Vegetation,Climate Change
Southwest Florida coastlines consist of approximately 300 km of barrier islands separated by tidal inlets and back bays. The nature of such systems is dynamic, though in developed areas with fixed coastlines, restoration and management are necessary to mitigate storm impacts. Natural and Nature-Based Features (NNBFs) utilize landforms such as sand barriers, dunes, and coastal vegetation as elements of a multi-tier coastal defense system, offering a more adaptable and sustainable alternative to coastal armoring by seawalls and revetments.
This study presents monitoring data and statistical analysis on the impacts of major hurricanes and the construction of NNBFs on two managed natural preserve areas surrounded by upland development in Southwest Florida. The analysis focuses on how these events influence water quality and correlate with declines in Submerged Aquatic Vegetation (SAV), which contains key elements for sustaining wildlife in the region.
The first case involves the natural system of Clam Bay Natural Resources Protection Area in Naples, which was utilized to discern statistically significant water quality trends in nutrients and water quality parameters relative to changes in seasonal variations and major storm events. Increases to levels of urban pollutants in lagoons and estuaries caused by increased debris, heavy rains, and storm surge following Hurricane Irma indicated an overall decline in ecosystem productivity, which was reflected in declining SAV trends connected using correlational analysis.
These findings were then utilized to support the conclusions of the second case study of Tigertail Lagoon in Marco Island, which involved the implementation of NNBFs and monitoring of SAV. Changes to water quality varied by storm, though turbidity and Total Suspended Solids (TSS) were consistently impacted by both storm and construction events. Certain parameters such as Total Nitrogen (TN) remained consistently above regionally accepted water quality standards.
In relation to SAV decline, correlational tests revealed that in zones of variable water flow, TN was primarily connected to SAV decline, whereas zones that lacked flushability, TSS and turbidity demonstrated a strong inverse correlation with SAV decline. Across zones, low Dissolved Oxygen (DO) levels indicated overall stress to the ecosystem.
Field studies revealed filamentous algae in Tigertail Lagoon, suspected to be Caulerpa fastigiate, appears to have the same conquering effect in Tigertail Lagoon as Polysiphonia subtilissima does in the Caloosahatchee and Caulerpa fastigiata does in Charlotte Harbor, in which the proliferation of the species coincides with seagrass decline and environmental health degradation. The Caulerpa species is known to create hypoxic events, which would explain observed low levels of DO in Tigertail Lagoon.
This study attributes declines in SAV to excessive TN from natural and anthropogenic sources that spurs algae growth, eutrophication, and hypoxic environments, as well as storm damage that increases turbidity, decreases light permeability, and raises temperatures of seagrass bed waters.
To evaluate the potential of NNBFs in the context of ecosystem resiliency, water quality recovery from NNBF construction was observed, which was found to return to pre-construction conditions. A decrease in orthophosphates further indicated potentially reduced influence of anthropogenic phosphate pollution. Though sediment disturbance during construction may increase turbidity, further establishment of NNBFs can help mitigate coastal storm damage and reduce anthropogenic pollutants.
This study highlights influences on water quality parameters in Southwest Florida for the analysis of ecosystem resiliency indicated using SAV. The results of this research are incorporated in regional environmental monitoring utilized to further environmental conservation and restoration efforts and can continue to be utilized for future adaptation and improvement measures.
This study presents monitoring data and statistical analysis on the impacts of major hurricanes and the construction of NNBFs on two managed natural preserve areas surrounded by upland development in Southwest Florida. The analysis focuses on how these events influence water quality and correlate with declines in Submerged Aquatic Vegetation (SAV), which contains key elements for sustaining wildlife in the region.
The first case involves the natural system of Clam Bay Natural Resources Protection Area in Naples, which was utilized to discern statistically significant water quality trends in nutrients and water quality parameters relative to changes in seasonal variations and major storm events. Increases to levels of urban pollutants in lagoons and estuaries caused by increased debris, heavy rains, and storm surge following Hurricane Irma indicated an overall decline in ecosystem productivity, which was reflected in declining SAV trends connected using correlational analysis.
These findings were then utilized to support the conclusions of the second case study of Tigertail Lagoon in Marco Island, which involved the implementation of NNBFs and monitoring of SAV. Changes to water quality varied by storm, though turbidity and Total Suspended Solids (TSS) were consistently impacted by both storm and construction events. Certain parameters such as Total Nitrogen (TN) remained consistently above regionally accepted water quality standards.
In relation to SAV decline, correlational tests revealed that in zones of variable water flow, TN was primarily connected to SAV decline, whereas zones that lacked flushability, TSS and turbidity demonstrated a strong inverse correlation with SAV decline. Across zones, low Dissolved Oxygen (DO) levels indicated overall stress to the ecosystem.
Field studies revealed filamentous algae in Tigertail Lagoon, suspected to be Caulerpa fastigiate, appears to have the same conquering effect in Tigertail Lagoon as Polysiphonia subtilissima does in the Caloosahatchee and Caulerpa fastigiata does in Charlotte Harbor, in which the proliferation of the species coincides with seagrass decline and environmental health degradation. The Caulerpa species is known to create hypoxic events, which would explain observed low levels of DO in Tigertail Lagoon.
This study attributes declines in SAV to excessive TN from natural and anthropogenic sources that spurs algae growth, eutrophication, and hypoxic environments, as well as storm damage that increases turbidity, decreases light permeability, and raises temperatures of seagrass bed waters.
To evaluate the potential of NNBFs in the context of ecosystem resiliency, water quality recovery from NNBF construction was observed, which was found to return to pre-construction conditions. A decrease in orthophosphates further indicated potentially reduced influence of anthropogenic phosphate pollution. Though sediment disturbance during construction may increase turbidity, further establishment of NNBFs can help mitigate coastal storm damage and reduce anthropogenic pollutants.
This study highlights influences on water quality parameters in Southwest Florida for the analysis of ecosystem resiliency indicated using SAV. The results of this research are incorporated in regional environmental monitoring utilized to further environmental conservation and restoration efforts and can continue to be utilized for future adaptation and improvement measures.