Event name: Horn Point Laboratory & Harriet Tubman Underground Railroad National Historical Park
Harmful Algal Blooms
One main area of research at the Horn Point Laboratory is coastal and ocean science, which includes the study of harmful algal blooms. Harmful algal blooms occur when certain species of phytoplankton grow uncontrollably and dominate aquatic ecosystems. One of the main drivers of this phenomenon is nutrient pollution, notably excess nitrogen and phosphorus from agricultural runoff, sewage, and stormwater. These nutrients allow algae to rapidly multiply, becoming a serious issue since it blocks sunlight from reaching plants underwater. Climate change is intensifying the problem with increasing temperatures and more storms that encourage conditions for blooms. Researchers at Horn Point Lab monitor algal blooms using both field sampling and modeling for data on nutrient levels, water temperature, oxygen, and phytoplankton populations in bodies of water such as the Chesapeake Bay in order to predict when and where blooms will occur. To address the issue, Horn Point researchers study how climate change will affect blooms and try to identify causes of nutrient pollution to limit the phenomenon.
Oyster Restoration
Another major research area at the lab is oyster restoration in the Chesapeake. Unfortunately, oyster populations are currently declining due to factors including overharvesting and habitat loss. This is significant to our environment because of the oysters' integral role in the Chesapeake Bay ecosystem: they help to filter water, which removes excess nutrients and clarifies the water. Plus, they are known to create reefs which serve as habitats for other marine life. In the field at large, scientists are monitoring oyster populations by measuring reef growth and water quality, since oysters are able to filter the surrounding waters to some extent. At Horn Point specifically, teams are working to address the decreasing survival and population of oysters through a number of efforts. These include breeding more disease-resistant oysters, with the help of a carefully crafted home-grown algae diet, and raising millions of oyster larvae in their hatcheries. Once developed, they are placed on reefs throughout the Chesapeake Bay to rebuild oyster populations and boost the bay's ecosystems.
Submerged Aquatic Vegetation
Horn Point Laboratory also places a significant focus on the restoration of submerged aquatic vegetation (SAV) in the Chesapeake Bay. The decline of underwater grasses is a key environmental issue because these grasses provide critical nursery habitats for species like crabs and fish. The Bay's once expansive meadows of SAV are dwindling due to a combination of nutrient pollution, poor water quality, and rising temperatures. Many species of grass currently reside in the more southern ranges of their habitats, which is subjecting them to thermal stress amidst climate change. When large populations of SAV die, the surrounding marine life suffers. To track these changes, scientists can monitor SAV beds using aerial surveys and by measuring water quality. Horn Point researchers developed an algorithm for calculating viable habitat conditions for SAV at coastal sites using water quality variables that dictate the availability of light to the leaves, allowing them to identify where grasses cannot survive, which informs which areas are most suitable for restoration. Meanwhile, on the restoration side, researchers at Horn Point Lab have led large efforts in the Chesapeake via production and planting of vegetative tubers for different grass species including sago pondweed and redhead grass, working with NOAA and the Army Corps of Engineers, using their research to directly benefit the Bay ecosystem.
Community Outreach
Horn Point Laboratory reaches out to the larger community by providing information about the key environmental issues that its scientists address. They are able to educate residents of Dorchester and Talbot counties via their free Community Science Talks. Ranging from topics like "Shells and rocks: paving the way to increase oyster habitat in Maryland's Chesapeake Bay" to "When waters bloom: Harmful Algal Blooms," these talks emphasize both the significance of various environmental issues and the impact of their research while teaching key background information on the science at hand. The lab also offers tours of their facility.
Harriet Tubman & the Natural World
On the excursion, I learned that Harriet Tubman used her knowledge of the local environment in many ways to help people escape slavery. One aspect of this skill was her ability to navigate the Underground Railroad stealthily using geography and the stars. Additionally, by crafting and administering herbal remedies from wild plants, she was able to treat people's illnesses as they traveled north together. She gained this knowledge of her natural surroundings throughout years of being hired out to work in the timber fields, build canals, and check muskrat traps.
Climate Threats to Historic Sites
Because some parts of the Underground Railroad are located in low-elevation areas like the Eastern Shore, rising sea levels are threatening to erode and even submerge the land. For example, the land where many key Harriet Tubman sites lie, including the farm she was enslaved on and the General Store she frequented, may be underwater in as soon as fifty years due to climate change. As these sites and routes start to disappear, it will be difficult for future generations to fully experience the history of Harriet Tubman and those whom she rescued.