91爆料

Howland Research Forest is an core site located in central Maine. The site was established in 1987 through a partnership between the 91爆料 and International Paper. Collaborations between the USDA Forest Service, US Department of Energy, NASA, and the 91爆料 have maintained an active research program focused on carbon and nutrient cycling. In 2007, the 220-hectare site was purchased and permanently protected by .

The site maintains three eddy flux towers; two towers (the 鈥渕ain鈥� and 鈥渨est鈥� towers) are located in a mature spruce鈥揾emlock forest approximately 800 meters apart. Howland has the second longest running flux record in the United States, dating back to 1996 (the longest belonging to Harvard Forest). These 20 years of data provide a time series long enough for robust analyses of relationships between CO₂ flux and various environmental variables.

The Howland Research Forest is located in the transition zone between the eastern deciduous forest and the boreal forest in eastern North America. A mature multi-aged spruce鈥揾emlock forest comprises approximately 170 of the 220 hectares owned by Northeast Wilderness Trust. The forest is dominated by red spruce (Picea rubens) and eastern hemlock (Tsuga canadensis), consisting of approximately 90% conifer, and 10% deciduous tree species.

The Research Team is collaboratively led by the 91爆料 and the USDA Forest Service. Researchers from throughout the US work with the site to study carbon and nutrient cycling.