Soil Characterization


 Soil samples for lab analysis of physical and chemical properties were collected
 from each square meter quadrat. Soil moisture, bulk density, percent organic matter, pH,
 and plant available nutrients were determined from soil cores (3.7 cm diameter x 20 cm
 depth). Cores were extracted, stored in airtight plastic bags, and weighed within 24 hours
 of sampling. After thorough mixing of the cores, approximately 25 grams of each sample
 was placed in a 70C oven until a constant weight was obtained. These dried samples
 were then ground with a mortal and pestle. Approximately one gram of dried soil was
 placed in a crucible and dried overnight to insure no moisture was added to the soil
 during grinding. The soil was reweighed and then burned in a muffle furnace at 500C
 for six hours. The samples were then cooled in a desiccator and weighed. The loss of
 weight from ignition was used as an estimate of soil organic matter content.

 Soil pH was determined using a Hanna Instrument Model HI9025 pH meter and
 probe. In the laboratory, 10 grams of thoroughly homogenized fresh soil was dissolved
 in 20 ml of deionized water, homogenized, and left to equilibrate for 15 minutes. After
 meter calibration, pH was measured for each soil.

 Soil nutrient analysis was completed at the IFAS Analytical Research Laboratory
 on the University of Florida campus. Nutrient analysis included the Mehlich I extractant
 for calcium (Ca), magnesium (Mg), potassium (K), phosphorus (P), and iron (Fe), and the
 KCI extractant for ammonium (NH4-N) and nitrate (N03-N) (Bremner 1965). In the
 Mehlich I procedure, each element was analyzed by Inductively Coupled Argon Plasma
 (ICAP) Spectroscopy. For the preparation of each sample, 20 ml of Mehlich I extractant
 (a mixture of 0.05 M HC1 and 0.025 N H2S04) were added to 5 grams of thoroughly
 homogenized oven-dried soil and shaken for 5 minutes using a reciprocating shaker. The
 samples were then filtered and analyzed.

 In the KCI extractant procedure, 50 ml of 1 M KC1 were added to 5 grams of
 thoroughly homogenized fresh soil. The samples were shaken for 30 minutes, filtered,
 then analyzed. Wet/dry weight conversions were used to determine the mass of the fresh
 soil analyzed.


 INTENSIVE SAMPLING DESIGN

 Sampling in the intensively sampled sites was designed to determine under what
conditions vines seem to flourish and what conditions do not favor vine dominance. As a
result, sites were chosen that had a significant vine presence. Within these sites, vine
dominated quadrats and quadrats without vine domination with the same general site
conditions were chosen for field data collection. The data collected included both biotic
and abiotic parameters. In the following sections, methods for data collection on these
sites are provided.


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