Many invasive species thrive on disturbance. Logging a forest, or flooding a wetland with nutrients and other chemicals, can create conditions that allow non-natives to move in. Not all non-natives are harmful, but some (the ones ecologists term invasive) can do great damage to the environment, the economy or both. Discovering which non-natives are dangerous, and what types of land uses and disturbances allow them to flourish, can help managers determine the best ways to preserve a healthy environment.
At SERC, ecologists are closely monitoring how ecosystems respond to disturbances such as logging. Will the same plant species return after logging has ended, or will the extra light give non-natives an opportunity to take over? One especially aggressive invader—Japanese stiltgrass, or Microstegium vimineum—can completely carpet the forest floor, smothering the growth of native tree seedlings and herbs. In wetlands, a European strain of the common reed Phragmites australis is spreading rapidly throughout the eastern U.S., a conquest partially aided by nutrient pollution.
Some land uses have positive impacts. One of the most ancient is found in shell middens, piles of oyster shells, crab shells and other materials Native Americans and settlers discarded after eating. SERC ecologists have discovered shell middens inject nutrients into the soil, even 3,000 years after their creation, enabling more diverse native plants to flourish in the soils above them.
Browse the projects below to learn more about how human history and invasive species collide.