Satellite maps are the latest innovation in detecting deforestation in the United States.
Led by Giorgios Mountrakis, who is an associate professor at the State University of New York College of Environmental Science and Forestry, the research on deforestation-tracking was backed by graduate student Sheng Yang for developing the forest tracking spatial tools.
The newly developed satellite mapping method "goes beyond forest quantity" and offers guidance toward conservation strategies as well, noted Mountrakis.
The study has been published in PLoS ONE.
North America has a history of dense forests. However, decades of agrarian activities, urban development, and other human actions deprived much of once-lush forest cover.
How Does It Work?
The newly developed method works around two variables: Observed Forest Cover Change and the Observed Attrition Forest Distance Change. The latter can detect the nearest forest from a given point.
It functions by contrasting the 1992 forest data versus 2001 mapped with the help of satellites.
The authors showed that in the nine years between the two given time frames, the nearest forest in the United States became far off by a third of a mile.
Forest Attrition Distance
The "forest attrition distance" is an index that reflects the loss of isolated forest patches, which the authors attributed to distancing from forests caused by the loss of forest patches.
As the distance between forests increases, it takes a toll on biodiversity and adds to soil erosion, local climate, and other conditions.
Using the metrics, they ascertained the loss of total forest cover from 1992 to 2001 to be 3 percent which translates to 35,000 square miles.
In the corresponding period, forest attrition distance increased 14 percent, which according to Mountrakis is "striking."
The difference in the two metrics is that forest attrition encompasses geographic distribution of forests. Despite similar percentage of loss of forests, forest attrition distances may not be the same for two forests and the ecological outcomes will also differ based on the pattern of tree removal.
High forest attrition means tree loss occurring in big swaths of trees and low attrition distance implies tree loss restricted to a few patches.
The authors noted that forest attrition has been acute in the western United States and said they are tracking the minute trends.
The study is impressive with the focus on geographic patterns in the context of fragmentation. Use of spatial processes for studying forest attrition, removal of forest patches leading to habitat loss and richness of species is significant.
The spatial indicator has the potential for universal use as an independent scale with a global potential. The proximity indicator is useful for evaluating forest attrition across regions and in mapping urban stratifications.
Meanwhile, reports are coming that renewed deforestation has hit Amazon forests after a lull under the "Save the Rainforest" movement.
In the Amazon basin, big deforestation activity is being led by the appetite for agricultural crops like soy and is defeating efforts to preserve biodiversity and fight climate change.
Washington-based organization Mighty Earth revealed a satellite data that showed Brazil's deforestation in areas where U.S. food companies Cargill and Bunge are active as agricultural traders.
The data said the savanna areas in Cerrado region had lost more than 321,000 acres in deforestation between 2011 and 2015.