CHAPTER 3
 PATTERNS OF SOIL CHEMICAL AND MICROBIAL PROPERTIES ALONG A
 CHRONOSEQUENCE INT WET LONGLEAF PINE FLATS OF FLORIDA

 Introduction

 Soil nutrient dynamics and their relationship to forest stand development have been

under investigation for some time (Odum, 1969; Vitousek and Reiners, 1975). Studies describing

soil nutrient status, in particular nitrogen, and its influence on stand productivity and canopy

nutrient dynamics have focused mostly on plantations (Morris and Boemer, 1998; Kirkman et al.

2001; Allen and Schlesinger, 2003), but research conducted in natural stands are also found in

the literature (Zak et al. 1990; Vance and Entry, 2000; Aravena et al. 2002; Chapman et al. 2003;

White et al. 2004). Similar studies are rare in the longleaf pine ecosystem, one of the most

threatened ecosystems in the United States (Wilson et al. 2002). For example, patterns of

nitrogen mineralization, the relationship between nitrogen levels and soil microbes, and how this

relationship changes over time, have not been given much attention (Johnston and Crossley,

2003). Such information could aid the efforts of restoration professionals who are interested in

not only restoring the structural attributes of the longleaf pine ecosystem, but its functional

attributes as well.

 One way to study the relationship between forest stand development and soil microbial

dynamics is to use a chronosequence of similar stands having different ages since stand

replacement (Pickett, 1989; Williamson et al. 2005). In an earlier investigation, Taylor et al.

(1999) studied forest floor microbial biomass of northern hardwood forest stands ranging from 3

years after clearcut to 120 years. These authors reported an increasing trend in microbial biomass

with age during the early successional stage. However, microbial biomass decreased with age

during the mid-aged stage, but increased again during the late successional stage. Soil organic

matter followed a pattern similar to microbial biomass. They further reported that fungal biomass