Tree Seedling Recruitment in a Temperate Deciduous Forest: Interactive Effects of Soil Moisture, Light, and Slope Position

Abstract

Predicted changes in global and regional precipitation regimes are likely to affect the distribution, structure, composition, diversity of plant communities [e.g., (1995); (1998); (2000)], and, in particular, forest ecosystems (Hanson and Weltzin 2000). Forests of the southeastern United States may be particularly vulnerable to changes in precipitation regimes and soil moisture contents because the increases in potential evapotranspiration predicted for this region may eventually exceed summer precipitation (National Assessment Synthesis Team 2000). These changes are predicted to occur at rates that may exceed the ability of forests to adapt through changes in species composition (Pastor and Post 1988; Davis 1989; Overpeck et al. 1991). Ultimately, the composition of forests under potential future climates will depend on interactive effects of regional and local abiotic conditions, biotic interactions, and species life-history traits. For example, coexistence mechanisms that govern the relative success of different tree species within a community will vary at each life-history stage of the tree (Nakashizuka 2001). Given adequate reproduction and seed dispersal, seedling recruitment and juvenile survivorship may dictate community composition (Harper 1977; Peet and Christensen 1987; Kobe 1996).KeywordsShade TreatmentSlope PositionTime Domain ReflectometrySoil Surface TemperaturePoplar SeedlingThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.