Much of the southeastern Department of Defense (DoD) landscape is dominated by southern pines; it is the most extensive matrix in which soldiers train and provides the ecological services (e.g., maintaining the land’s nutrient capital, providing habitat for native species, and protecting watersheds) on which the military mission relies. Currently, loblolly pine forests have been reported to be declining in central Alabama and Georgia. However, it is not known whether the observed phenomenon is distinguishable from natural senescence and mortality associated with an aging forest or if it is occurring in other pine species. If accelerated mortality is documented, there is an additional need to describe its spatial extent and to understand temporal dynamics.
This project is designed to answer two main questions, each with multiple specific objectives. Question 1: Is there a decline in southeastern pine forests (indicated by accelerated mortality or generalized decline in canopy health) that is measurably different from historical patterns of growth and mortality? Related technical objectives are to (1) develop a practical set of criteria/thresholds that can be used to classify observed mortality or growth patterns as “accelerated” compared to historical norms and (2) identify which southern pine species show evidence of decline. Question 2: For species in which accelerated mortality is indicated, what are the temporal and spatial patterns of the phenomenon? Related technical objectives are to (1) determine rates of pine forest decline at the stand level; (2) characterize the spatial patterns of pine decline at landscape and regional scales; and (3) estimate the spatial extent of the declining forest at landscape and regional scales.
The study will quantify growth and mortality for loblolly, longleaf, and slash pine in five southeastern states (Alabama, Georgia, South Carolina, North Carolina, and northern Florida) and at three spatial scales (stand, landscape, and region). A combination of data from field surveys, long-established forest inventory and analysis plots (FIA data), other recently established sampling plots, and various remote sensing data sources will be used to achieve the research objectives. Declining forest health will be indicated by continuous decreases in canopy foliage biomass, reductions in radial growth, and/or abnormally high mortality rates. Foliage biomass will be indirectly estimated by remote sensing techniques, while radial growth and mortality will be evaluated based on field survey, continuous forest inventory and analysis data, and repeated measures in newly established research plots.
This project will generate information needed to forecast potential adverse impacts on the region’s natural resources and, in particular, on the ability of the land to sustain DoD's training mission. Understanding patterns and rates of changing forest health provides the basis for strategic management of resources for recovery and sustainable use. (Anticipated Project Completion - 2014)