Monday, August 6, 2007

PS 10-121: Measuring departure of forest plant communities from reference conditions through changes in structure and composition

Maria E. Melnechuk, The Nature Conservancy

Conservation forestry is defined as a set of forest management practices that sustains ecological systems (biodiversity) and protects social values while being economically profitable.  This strategy is crucial for conservation in the Upper West Gulf Coastal Plain ecoregion of Arkansas due to large acreages in both private and industrial timber management.  Two projects implementing conservation forestry practices, including prescribed fire, are the Moro-Big Pine Wildlife Management Area and the Blackland Prairie Conservation Project.  Prior to treatment baseline plant community monitoring was conducted.  The plant community monitoring utilized a nested quadrat method with four, 1 m x 1 m herbaceous quadrats and two 11.7-foot radius shrub quadrats nested within one 10-m radius tree plot.  Initial success criteria are based on the density and diversity of current plant species as compared to the historic conditions derived from local data and vegetation models.  Analyses at both sites indicate the current plant communities are significantly departed from reference conditions based on forest structure and composition (P ≤ 0.05).  The reintroduction of fire and appropriate timber management will reduce this departure by decreasing the woody component of grasslands, favoring native warm season grasses, restoring structure to the degraded woodlands, and reinvigorate the forest-woodland understory.  A variety of species will be benefited by restoration activities, including wintering and breeding grassland bird species.  Continued evaluation of conservation forestry’s impacts on biodiversity will allow managers to measure progress toward restoring reference conditions.