Invasive species, both plant and animal, are reshaping America’s landscapes in profound and often irreversible ways. Non-native species that induce ecological or economic damage are, or act as, agents of change that can disrupt ecosystems and alter landforms. According to a study by Purdue University and the University of Kentucky, invasive species can dramatically alter sedimentation and coastlines, among other natural processes. These changes, which can persist for decades or centuries, highlight the necessity for strategic management to address their effects before they become permanent features of the landscape.
How Do Invasive Species Transform Landscapes?
Invasive species transform landscapes in numerous ways, including burrowing, trampling vegetation, and changing the course of waterways. Plants can, for instance, stabilize soil in unintended ways that alter sedimentation rates or create new landforms.
In one instance, Spartina grass was introduced to inhibit erosion along China’s coastline and transformed 400 square miles of mudflats into salt marshes in less than 10 years, erasing beaches altogether.
Similarly, invasive animals such as earthworms break up soil structures to depths of up to seven feet, changing the soil’s composition and ability to hold water. These changes in landforms illustrate how complex the interactions between invasive organisms and their environments can be.
Vulnerable Zones: High-Risk Areas for Invasion
Some ecosystems are more vulnerable to invasive species than others. Wetlands, salt marshes, beaches, and dunes — dynamic regions, where land and water systems overlap, are hotspots where the transformations take place.
The rapid changes in these regions amplify the severity of the impacts. In contrast, forests exhibit slower responses due to the longevity of trees and slower ecosystem turnover. However, even forests are not spared from invasive plants and animals reshaping them over time.
Changes in the Structure of Ecosystems
Invasive species often build new biological structures in the ecosystems they invade. Plants create dense layers of leaf litter or peat bogs that alter habitat conditions, while animals such as beavers construct dams that radically reshape waterways.
Burrowing creatures such as termites create mounds that can change the soil composition and drainage patterns. These structural changes can have cascading effects on native flora and fauna, further disrupting ecological balance.
Restoration and Management Challenges
Restoring landscapes impacted by invasive species is an arduous process due to the deeply embedded nature of these changes. Decisions about where to intervene must weigh the feasibility of reversing damage against the likelihood of success.
Making this challenge worse is the absence of standardized metrics for assessing the effects of invasive species on landscapes, which creates challenges when trying to compare changes in different environments.
Research on the geographic distributions of these impacts is critical for developing better tools for understanding and managing them. This research will be collaborative between biogeographers and invasive species experts.
Proactive Management
Natural resources managers must prioritize identifying high-risk areas and implementing preventive measures to curb the spread of invasive species. Focusing efforts on vulnerable areas and employing long-term monitoring strategies could allow for maintaining ecological integrity and avoiding irreversible damage.
Though most consider aggressive and invasive plant species destructive forces, the researchers argue that understanding their effects presents another opportunity for improving landscape management practices in America’s diverse ecosystems.
