Document: DAL-3-63-41

Spatial heterogeneity during the early stages of secondary succession in a slash-pine forest.

GUO, D.* ¹, P.MOU ¹ and R.J.JONES ²

Virginia Polytechnic Institute and State University, Blacksburg, VA 24061USA ¹
Joseph W. Jones Ecological Research Center, Newton, GA 31770 USA ²

Abstract:
Spatial heterogeneity plays an important role in ecosystem development. A study was conducted in a slash-pine forest at the Savannah River Site in Aiken, SC, 1) to examine the impact of two types of disturbances (whole-tree harvest vs. girdling) on the spatial variations of soil and forest floor variables (soil moisture, pH, available N and P, soil and litter total C and N, litter mass and depth); 2) to investigate temporal changes of the variations of these variables over a three-year period; and 3) to detect the existence of functional heterogeneity in the system. Global variation, semivariogram, and cross-variogram were used to characterize structural heterogeneity of each variable and relationships among the variables. Spatial patterns changed dramatically in the first two years after disturbance. The whole-tree harvest that churned the litter layer had significantly different effects on spatial patterns of edaphic variables than the girdling treatment that left the litter layer physically intact. By the second year, functional heterogeneity started to emerge in the disturbed plots. This data agrees with the predictions by a previously proposed conceptual model that describes spatial pattern changes in secondary forest succession.

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This abstract is being presented at: 10:30 AM in session:
Poster Session #12: Disturbance Ecology.