IP_Poster_Payne
1
Introduction Wetlands are some of the most fragile, yet crucial, ecosystems found in the United States. Louisiana particularly has hundreds of miles worth of dynamic wetlands along a gradual slope, which makes them especially at risk of being inundated with high salinity water due to sea-level rise (SLR) from climate change. SLR has been reported for many years now, as carbon dioxide (CO 2 ), methane, and other greenhouse gasses have begun to warm the Earth at a rapid rate (Williams et al. 2002). This rate is only expected to increase due to increased atmospheric greenhouse levels and arctic ice melt, and by 2100 it is estimated that the parish of Terrebonne, LA will face ocean water inundation levels of 5.7ft (Strauss et al. 2015). Physical water cover is not the only impact that we need to be concerned with, though, as other factors come into play due to high-salinity water being in such close proximity. Some of the wetlands along the coast are salt-water or estuarine based, so they may be able to handle an increase in ocean water, but others are freshwater based, so the introduction of an increase in salinity could have even more devastating effects or aquatic and terrestrial flora and fauna. Depending on the type of wetland, effects from erosion can be seen conservatively within 1000 feet (U.S. Army Corps of Engineers 2005). The effects of sea spray can be seen within 300 feet (McElfish et al. 2008). What coastal wetlands in the parish of Terrebonne, Louisiana are at risk of being lost due to climate change-induced sea level rise (SLR) as predicted by the NOAA? Methods Data Sources § ATLAS: Louisiana Statewide GIS (LDEQ). 2004. Elevation Map from 1:24,000 DEM Mosaic. www.atlas.lsu.edu §US FWS. 2015. Louisiana Seamless Wetlands. http://www.fws.gov/wetlands/Data §GeoCommunicator. 2000. Terrebonne, Louisiana Geographic Boundary. http://www.geocommunicator.gov Literature Cited Discussion Contrary to what some may believe when this research question was posed, the wetlands most at risk of suffering negative effects from sea-level rise by the year 2100 are in the northwestern portion of Terrebonne, Louisiana (Figure 2). That is because these wetlands have a low tolerance for higher amounts of salinity, as they are freshwater based, such as freshwater emergent wetlands (medium risk), freshwater forested shrub wetlands, freshwater ponds, riverines, and lakes (high risk) (Table 1). Interestingly, the wetlands that have the lowest risk posed against them are towards the middle of the area of interest (Figure 2), but Figure 1 illustrates that this is because there appears to be a gradual sloping increase in elevation starting in the lower middle of Terrebonne and proceeding to the northeastern part of the parish. This is also where the effects from sea spray and erosion are most apparent (Figure 3) because of the lower water levels changing their primary influence on the land from a complete change in environment to a gradual change. The repeated saturation followed by receding water levels from the tides will cause erosion over time, and the wave action will stir up sea spray that could pose a threat, especially to terrestrial flora, in low-salinity wetlands. Studies such as this are becoming ever-more crucial as climate change progresses, especially when anthropogenic causes are not being remedied quickly enough. This study specifically takes a broad look at a date quite a ways away so as to show the kind of damage that can be done to our coastlines. It is the goal of this research to raise awareness of the risks that wetlands—some of our most crucial ecosystems—will face in the coming years if major changes are not made to reverse some of the environmental damage that has already been done. As seen in Figure 2, the risks only seem to increase towards the northern boundary of Terrebonne, and the wetlands of Louisiana continue on for many miles to the East, West, and North. This study only looked at one parish, but there are many others to worry about, not to mention the risks that coastlines all over to world face due to sea-level rise. §Williams K., Pinzon Z.S., Stumpf N., Hageman R.P., Raabe, E. A. 2002. Sea-level rise and costal forests on the Gulf of Mexico. U.S. Geological Survey. 99 (441). §Strauss B., Tebaldi C., Kulp S . 2015. Louisiana and the Surging Sea. Climate Central, Princeton. §McElfish J., Kihslinger R., Nichols S. 2008. Setting Buffer Sizes for Wetlands. National Wetlands Newsletter, Washington D.C. 30(2) §U.S. Army Corps of Engineers. 2005. Guidance on Buffers and Ratios. U.S. Department of Environmental Protection. Protecting and Managing Wetlands Vol. 2, Seattle. Evaluating Sea-Level Rise (SLR) in the Coastal Wetlands of Terrebonne, Louisiana Jade Payne 1 and Michael Gilbrook 2 Office of Interdisciplinary Studies 1 and Department of Biology 2 , University of Central Florida Results In order to locate the wetlands that are of high risk of negative impacts due to the consequences of sea-level rise (SLR), we created a model that considers the potential impact of inundation, erosion, sea spray, and the sensitivity of the types of wetlands in Terrebonne, Louisiana. (Figure 1). Before the model was run, pre-processing steps were conducted such as clipping the initial Louisiana Wetlands data layer to the boundary of Terrebonne in order to not overwhelm the computer. Following the necessary pre-processing procedures, the wetlands layer was classified according to the sensitivity of wetland type to high-salinity water, as shown in Table 1. The elevation layer was classified according to the threat that any one point would have concerning a predicted 5.7ft inundation amount (Table 1). The elevation layer was also used to select only those areas of wetland that are not completely inundated with water, which then received two different buffers: one to account for erosion (1 mile) (U.S. Army Corps of Engineers 2005) due to saturation and sediment movement from closer inundation, and one to account for sea spray due to wave action proximity (0.5 miles) (Table 1) . Both buffers take into account tidal fluctuation. After each necessary input layer was ready for the final cell statistical analysis, the sum of the previous ranks was taken and finally reclassified according to risk level to produce the final output and the answer to our question (Figure 2). Figure 1. A model that analyzes the risk that wetlands have due to sea-level rise, accounting for effects of inundation, sensitivity of wetland type, erosion, and sea spray. Insert Figure Here Based on the risk model (Figure 1), the wetlands closest to the ocean show intermediate risk due to the impacts of sea-level rise, with the wetlands further inland appearing to be much more sensitive to this environmental change (Figure 2). The lowest risk areas are located roughly in the middle of the area of interest (AOI), and this is important to notice in conjunction with the wetland type and sporadic increases in elevation in these areas (Figure 3). There are very few tracts of wetland that will be harmed a minimal amount Figure 2. A map showing the risk that wetlands in Terrebonne, Louisiana face due to impending sea-level rise by the year 2100. Figure 3. The risk due to wetland type (Top Left), risk due to inundation from high-salinity water (Top Right), risk due to erosion (Bottom Left), and risk due to sea spray (Bottom Right). Table 1. A table illustrating how each data layer was classified in the spatial analysis model. Figure 3, to the left, shows a graphical representation of the layers that were inputted into the model after they had been classified according to potential risk from SLR. The most apparent risk is inundation from high salinity water as shown in the top right of Figure 3—It is an elevation-based layer. Wetland type is more concerning in the northern portion of Terrebonne as these locations are not prone to interacting with high levels of salinity. The north eastern part of the parish is where the effects from erosion and sea spray play a role, as this is where the wetlands will not be completely covered with water, so the gradual impact of saturation, sediment movement, and wave action will be seen towards the edges of the water line.
-
Upload
jade-payne -
Category
Documents
-
view
30 -
download
0
Transcript of IP_Poster_Payne
IntroductionWetlands are some of the most fragile, yet crucial, ecosystems found in the United States. Louisiana particularly has hundreds of miles worth of dynamic wetlands along a gradual slope, which makes them especially at risk of being inundated with high salinity water due to sea-level rise (SLR) from climate change. SLR has been reported for many years now, as carbon dioxide (CO2), methane, and other greenhouse gasses have begun to warm the Earth at a rapid rate (Williams et al. 2002). This rate is only expected to increase due to increased atmospheric greenhouse levels and arctic ice melt, and by 2100 it is estimated that the parish of Terrebonne, LA will face ocean water inundation levels of 5.7ft (Strauss et al. 2015).Physical water cover is not the only impact that we need to be concerned with, though, as other factors come into play due to high-salinity water being in such close proximity. Some of the wetlands along the coast are salt-water or estuarine based, so they may be able to handle an increase in ocean water, but others are freshwater based, so the introduction of an increase in salinity could have even more devastating effects or aquatic and terrestrial flora and fauna. Depending on the type of wetland, effects from erosion can be seen conservatively within 1000 feet (U.S. Army Corps of Engineers 2005). The effects of sea spray can be seen within 300 feet (McElfish et al. 2008).
What coastal wetlands in the parish of Terrebonne, Louisiana are at risk of being lost due to climate change-induced sea level rise (SLR) as predicted by
the NOAA?
Methods
Data Sources§ ATLAS: Louisiana Statewide GIS (LDEQ). 2004. Elevation Map from 1:24,000 DEM Mosaic. www.atlas.lsu.edu
§US FWS. 2015. Louisiana Seamless Wetlands. http://www.fws.gov/wetlands/Data
§GeoCommunicator. 2000. Terrebonne, Louisiana Geographic Boundary. http://www.geocommunicator.gov
Literature Cited
DiscussionContrary to what some may believe when this research question was posed, the wetlands most at risk of suffering negative effects from sea-level rise by the year 2100 are in the northwestern portion of Terrebonne, Louisiana (Figure 2). That is because these wetlands have a low tolerance for higher amounts of salinity, as they are freshwater based, such as freshwater emergent wetlands (medium risk), freshwater forested shrub wetlands, freshwater ponds, riverines, and lakes (high risk) (Table 1).
Interestingly, the wetlands that have the lowest risk posed against them are towards the middle of the area of interest (Figure 2), but Figure 1 illustrates that this is because there appears to be a gradual sloping increase in elevation starting in the lower middle of Terrebonne and proceeding to the northeastern part of the parish. This is also where the effects from sea spray and erosion are most apparent (Figure 3) because of the lower water levels changing their primary influence on the land from a complete change in environment to a gradual change. The repeated saturation followed by receding water levels from the tides will cause erosion over time, and the wave action will stir up sea spray that could pose a threat, especially to terrestrial flora, in low-salinity wetlands.
Studies such as this are becoming ever-more crucial as climate change progresses, especially when anthropogenic causes are not being remedied quickly enough. This study specifically takes a broad look at a date quite a ways away so as to show the kind of damage that can be done to our coastlines. It is the goal of this research to raise awareness of the risks that wetlands—some of our most crucial ecosystems—will face in the coming years if major changes are not made to reverse some of the environmental damage that has already been done.
As seen in Figure 2, the risks only seem to increase towards the northern boundary of Terrebonne, and the wetlands of Louisiana continue on for many miles to the East, West, and North. This study only looked at one parish, but there are many others to worry about, not to mention the risks that coastlines all over to world face due to sea-level rise.
§Williams K., Pinzon Z.S., Stumpf N., Hageman R.P., Raabe, E. A. 2002. Sea-level rise and costal forests on the Gulf of Mexico. U.S. Geological Survey. 99 (441).
§Strauss B., Tebaldi C., Kulp S . 2015. Louisiana and the Surging Sea. Climate Central, Princeton.
§McElfish J., Kihslinger R., Nichols S. 2008. Setting Buffer Sizes for Wetlands. National Wetlands Newsletter, Washington D.C. 30(2)
§U.S. Army Corps of Engineers. 2005. Guidance on Buffers and Ratios. U.S. Department of Environmental Protection. Protecting and Managing Wetlands Vol. 2, Seattle.
Evaluating Sea-Level Rise (SLR) in the Coastal Wetlands of Terrebonne, LouisianaJade Payne1 and Michael Gilbrook2
Office of Interdisciplinary Studies1 and Department of Biology2, University of Central Florida
Results
In order to locate the wetlands that are of high risk of negative impacts due to the consequences of sea-level rise (SLR), we created a model that considers the potential impact of inundation, erosion, sea spray, and the sensitivity of the types of wetlands in Terrebonne, Louisiana. (Figure 1). Before the model was run, pre-processing steps were conducted such as clipping the initial Louisiana Wetlands data layer to the boundary of Terrebonne in order to not overwhelm the computer.
Following the necessary pre-processing procedures, the wetlands layer was classified according to the sensitivity of wetland type to high-salinity water, as shown in Table 1. The elevation layer was classified according to the threat that any one point would have concerning a predicted 5.7ft inundation amount (Table 1). The elevation layer was also used to select only those areas of wetland that are not completely inundated with water, which then received two different buffers: one to account for erosion (1 mile) (U.S. Army Corps of Engineers 2005) due to saturation and sediment movement from closer inundation, and one to account for sea spray due to wave action proximity (0.5 miles) (Table 1) . Both buffers take into account tidal fluctuation.After each necessary input layer was ready for the final cell statistical analysis, the sum of the previous ranks was taken and finally reclassified according to risk level to produce the final output and the answer to our question (Figure 2).
Figure 1. A model that analyzes the risk that wetlands have due to sea-level rise, accounting for effects of inundation, sensitivity of wetland type, erosion, and sea spray.
Insert Figure Here
Based on the risk model (Figure 1), the wetlands closest to the ocean show intermediate risk due to the impacts of sea-level rise, with the wetlands further inland appearing to be much more sensitive to this environmental change (Figure 2). The lowest risk areas are located roughly in the middle of the area of interest (AOI), and this is important to notice in conjunction with the wetland type and sporadic increases in elevation in these areas (Figure 3). There are very few tracts of wetland that will be harmed a minimal amount
Figure 2. A map showing the risk that wetlands in Terrebonne, Louisiana face due to impending sea-level rise by the year 2100.
Figure 3. The risk due to wetland type (Top Left), risk due to inundation from high-salinity water (Top Right), risk due to erosion (Bottom Left), and risk due to sea spray (Bottom Right).
Table 1. A table illustrating how each data layer was classified in the spatial analysis model.
Figure 3, to the left, shows a graphical representation of the layers that were inputted into the model after they had been classified according to potential risk from SLR. The most apparent risk is inundation from high salinity water as shown in the top right of Figure 3—It is an elevation-based layer. Wetland type is more concerning in the northern portion of Terrebonne as these locations are not prone to interacting with high levels of salinity. The north eastern part of the parish is where the effects from erosion and sea spray play a role, as this is where the wetlands will not be completely covered with water, so the gradual impact of saturation, sediment movement, and wave action will be seen towards the edges of the water line.
