Determinants of leaf litter patchiness in mixed species New Jersey pine barrens forest and its possible influence on soil and soil biota

We have identified the importance of ground layer ericaceous shrub density as a determinant of leaf litter patch size in upland oak/pine communities of the New Jersey pine barrens. Litter patch area is directly proportional to the number of ericaceous stems. This observation has been confirmed by experimentation where leaf litter patches accumulated under artificial stems for a period of 2 years. Leaf litter patches of different sizes contain differing proportions of leaf species. Large patches contain a significantly higher proportion of oak leaves than small patches. Difference in physical structure of large and small patches, due to leaf species composition and due to differential leaf chemistries, result in differences in soil characteristics and soil biota under the patches. Soil moisture and organic matter content of upper soil layers are greater under large litter patches than under small ones. We have preliminary evidence that these changes influence the community structure of ectomycorrhizae developing under patches of different sizes.