Soil Types of Part of Penobscot County, Maine in the Forest Ecosystem Dynamics Project Spatial Data Archive

Forest Ecosystem Dynamics (FED) Project Spatial Data Archive: County Soil Survey Data with Attributes

The Biospheric Sciences Branch (formerly Earth Resources Branch) within the Laboratory for Terrestrial Physics at NASA's Goddard Space Flight Center and associated University investigators are involved in a research program entitled Forest Ecosystem Dynamics (FED) which is fundamentally concerned with vegetation change of forest ecosystems at local to regional spatial scales (100 to 10,000 meters) and temporal scales ranging from monthly to decadal periods (10 to 100 years). The nature and extent of the impacts of these changes, as well as the feedbacks to global climate, may be addressed through modeling the interactions of the vegetation, soil, and energy components of the boreal ecosystem.

The Howland Forest research site lies within the Northern Experimental Forest of International Paper. The natural stands in this boreal-northern hardwood transitional forest consist of spruce-hemlock-fir, aspen-birch, and hemlock-hardwood mixtures. The topography of the region varies from flat to gently rolling, with a maximum elevation change of less than 68 m within 10 km. Due to the region's glacial history, soil drainage classes within a small area may vary widely, from well drained to poorly drained. Consequently, an elaborate patchwork of forest communities has developed, supporting exceptional local species diversity.

Additionally, almost 450 ha of the surrounding area consists of bogs and other wetlands. Generally, the soils throughout the forest are glacial tills, acid in reaction, with low fertility and high organic composition. These soils are classified primarily within three suborders: orthods, orchrepts, and aquepts. The climate is chiefly cold, humid, and continental and the region exhibits a snowpack of up to 2 m from December through March.

The original soil polygons were obtained by digitizing a 1963 USDA General Soil Map of Penobscot County, Maine. All of the soil symbols used were taken directly off of the county soil map. Data from the State Soil Geographic Database (STATSGO) were cross-matched. The county symbol was chosen as the identifier, and a STATGO identifier that best "fits" the county soil identifier was selected. The original maps used for the digitization came in 6 map sheets. All of the sheets were digitized, corrected, edge-matched, and appended. Once this was finished, topology was built, new items and attributes were added.

The data in its current form can be used to delineate basic soil groups. However, because the STATSGO map unit identifier is located in each polygon the user can link any of the other STATSGO data sets depending on the desired information. The identifier is the key for creating a very detailed and thorough soils data set. Once linked the data can be used for ecological modeling, resource management, and many other applications.