Invasive plants transform the three-dimensional structure of rain forests

Area of Science:

• Ecology
• Environmental Science
• Remote Sensing

Background:

• Biological invasions are a major driver of global environmental change.
• Assessing the regional dynamics and impacts of invasive species is challenging.

Purpose of the Study:

• To map the location and ecological impacts of five invasive plant species in Hawaiian ecosystems.
• To identify how these invaders alter the three-dimensional (3D) structure of native rainforests.
• To demonstrate the utility of airborne remote sensing for invasive species management.

Main Methods:

• Deployment of an airborne remote sensing system.
• Mapping invasive plant species distribution and impacts across 221,875 hectares of Hawaiian ecosystems.
• Analysis of changes in the 3D structure of native rainforests.

Main Results:

• Four distinct ways invasive species transform rainforest 3D structure were identified.
• Invasive trees replaced native species at various canopy levels, from ground to all levels.
• Specific examples include lowland to montane forests and lowland forests with nitrogen-fixing trees.

Conclusions:

• Diverse alien plant species, representing different functional types, are fundamentally altering native Hawaiian rainforest 3D structure.
• Airborne mapping effectively identifies and tracks invasive species spread.
• This strategy provides crucial geographic data for conservation and management of invaded ecosystems.