Experts from the US Forest Service and the Carnegie Institution have developed a new laser system that allows them to use a plan for monitoring changes that might have occurred in tropical rain forests. The changes refer to the influence of outside intrusive plant species, as well as to the effect the spread or reduction of tree surfaces has on the landscape around the forests. The new system also allows researchers to assess the threat level for a certain forest, or portion of forest, as well as to determine time lines and create estimates as to when a certain ecosystem might heal itself, or disappear altogether.

In a new study published in the January issue of the journal Ecosystems, Carnegie Institution Department of Global Ecology expert Gregory Asner says that "Our results clearly show the interactive role that climate and invasive species play on carbon stocks in tropical forests, and this may prove useful in projecting future changes in carbon sequestration in Hawaii and beyond."

"These findings showed airborne data correlated with data derived from study plots on the ground. They also demonstrated what might be the most important environmental factors affecting forest biomass and carbon sequestration," US Forest Service Institute of Pacific Islands Forestry ecologist Flint Hughes, who is also one of the authors of the Ecosystems paper, adds.

The new laser system can measure elevation on a designated area with a precision of +/- 6 inches, which means that it creates a faithful image of the region being photographed. It can allows scientists operating it to create superimposed charts that could show them the evolution of the area over a period of time. Based on monthly or quarterly observations, the state of some of the world's oldest and most precious forests could be monitored thoroughly, and any change recorded.

The airplane measurements are then cross-referenced with data recorded in the forests themselves, such as tree diameter, canopy height and richness, and wood density. Foreign and invasive plants can thus be easily identified, and even eliminated if the situation demands it. Biomass levels that intruders produce affect the trees' ability to retain carbon dioxide, the main greenhouse gas responsible for global warming.

So, researchers are trying to identify any phenomenon that may affect the way carbon is naturally stored before it becomes a part of the ecosystem, and thus impossible to stop.