Peat collapse and vegetation shift at Hickory Point
Dates
Publication Date
2022-11-16
Start Date
2013-09-05
End Date
2021-11-11
Citation
Middleton, B.A., and David, J.L., 2022, Peat collapse and vegetation shift at Hickory Point: U.S. Geological Survey data release, https://doi.org/10.5066/P99LLMXQ.
Summary
This work captures a multi-year progression from 2013 to 2021 of change in the height of the topographic surface and freshwater status of the rooting zone that may indicate impending vegetation transition. Two Surface Elevation Tables (SETs) in a tidal Taxodium distichum swamp at Hickory Point State Forest near Pocomoke City, Maryland were used to collect data on the height of the topographic surface established with respect to a local vertical datum. Annual root production over time was measured by collecting data on ingrowth into mesh root bags. Root bags were collected at 5 set locations within the study area and analyzed to determine the weight in grams of new root production per meter cubed each year. This project also uses data [...]
Summary
This work captures a multi-year progression from 2013 to 2021 of change in the height of the topographic surface and freshwater status of the rooting zone that may indicate impending vegetation transition. Two Surface Elevation Tables (SETs) in a tidal Taxodium distichum swamp at Hickory Point State Forest near Pocomoke City, Maryland were used to collect data on the height of the topographic surface established with respect to a local vertical datum. Annual root production over time was measured by collecting data on ingrowth into mesh root bags. Root bags were collected at 5 set locations within the study area and analyzed to determine the weight in grams of new root production per meter cubed each year. This project also uses data from a CTD DIver probe in a well located next to one of the SETs in the study site 48 cm below soil level. The data also documents the depth, salinity, and pH of the water as well as the vegetation found in the freshwater swamps of Hickory Point. In 2013 five Taxodium distichum trees along a 125 m long transect were outfitted with dendrobands. Each year the growth of the T. distichum trees was measured in terms of the ratio of that year's circumference to the previous year's circumference. Tree growth was measured until the year the tree died or the conclusion of the study in 2021. In November of 2021, the height, density, and species richness of all tree species were recorded in five plots along a 175 m transect. This data was divided into catagories depending on if the tree was alive, dead, or a sapling. Emergent species' height, density, and richness was also recorded.
Click on title to download individual files attached to this item.
Hickory_Point.xml Original FGDC Metadata
View
24.99 KB
application/fgdc+xml
Related External Resources
Type: Related Primary Publication
Middleton, B.A., and David, J.L., 2022, Trends in vegetation and height of the topographic surface in a tidal freshwater swamp experiencing rooting zone saltwater intrusion: Ecological Indicators, v. 145, art. 109637, https://doi.org/10.1016/j.ecolind.2022.109637.
Decrease in the elevation of coastal wetlands is of worldwide concern because of its relationship to peat loss, coastal carbon, and biodiversity in freshwater wetlands. Peat building is essential to promote the resilience of coastal wetlands to salinity intrusion from sea-level rise, hurricanes, and freshwater over-usage. The process is facilitated by the active contribution of plant materials through root production. The data measures the amount of roots produced each year, which will help indicate trends in peat stability. Following events such as hurricanes and offshore storms, salinity intrusion can occur in coastal freshwater swamps causing vegetation shifts along with changes in species' growth rates and mortality. As sea-levels rises, these freshwater wetlands are subjected to increased salinity exposure from surface and groundwater sources. The data provides groundwater properties from a well located in a coastal wetland environment to assist with understanding the tidal freshwater swamp trends.
