The relationships between nitrogen (N), defoliation, and plant growth in
nursery plants were studied using almond {Prunus dulcis (Mill) D. A. Webb) trees. In
several experiments the effects of N source and availability on tree growth, N uptake,
N remobilization, and nonstructural carbohydrates (TNC) were investigated to
determine the most...
Longleaf pine (Pinus palustris Mill.) forests are characterized by unusually high understory plant species diversity, but models describing understory ground cover biomass, and hence fuel load dynamics, are scarce for this fire-dependent ecosystem. Only coarse scale estimates, being restricted on accuracy and geographical extrapolation, are available. We analyzed the dynamics...
Interception of precipitation by forest canopies has been found previously to reduce rainfall intensity, but this effect is poorly understood. The goal of this research is to quantify the attenuation of rainfall intensity by forest canopy interception, with the specific objective of estimating the contribution of this attenuation to hillslope...
The eddy-covariance method often underestimates fluxes under stable, low-wind conditions at night when turbulence is not well developed. The most common approach to resolve the problem of nighttime flux underestimation is to identify and remove the deficit periods using friction-velocity (u*) threshold filters (u*[superscript Th]). This study modifies an accepted...
Marine bacteria play vital roles in every niche of the ocean, from small-scale symbioses to large-scale productivity and the regulation of Earth’s climate. Recent advances in molecular tools now allow us to probe the genetic potential of entire microbial communities. The next step is linking these diverse communities to the...
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National Academy of Sciences 100(3), 1051-1055.
Ducklow, H.W., Steinberg, D.K., and Buesseler, K.O
The exchange of carbon dioxide is a key measure of ecosystem metabolism and a critical intersection
between the terrestrial biosphere and the Earth’s climate. Despite the general agreement that
the terrestrial ecosystems in North America provide a sizeable carbon sink, the size and distribution
of the sink remain uncertain. We...
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removing periods of inadequate mixing or low turbulence
(Hollinger and Richardson, 2005; Loescher et al
Forest soils contain a substantial portion of global terrestrial carbon stores. Forest management can influence the soil carbon pool and how soil organic matter functions. The long-term productivity of forests is an ongoing goal where land managers utilize biomass and timber. A site-specific understanding of intensively managed forests can ensure...
Assessment of forest carbon storage dynamics requires a variety of techniques including simulation models. We developed a hybrid model to assess the effects of silvicultural management systems on carbon (C) budgets in longleaf pine (Pinus palustris Mill.) plantations in the southeastern U.S. To simulate in situ C pools, the model...
Forest ecosystem dynamics emerges from nonlinear interactions between adaptive biotic agents (i.e., individual trees) and their relationship with a spatially and temporally heterogeneous abiotic environment. Understanding and predicting the dynamics resulting from these complex interactions is crucial for the sustainable stewardship of ecosystems, particularly in the context of rapidly changing...