Hurricane disturbances have profound impacts on ecosystem structure and function, yet their effects on ecosystem CO2 exchange have not been reported. In September 2004, our research site on a fire-regenerated scrub-oak ecosystem in central Florida was struck by Hurricane Frances with sustained winds of 113 km h−1 and wind gusts as high […]
Forest management, climatic change, and atmospheric N deposition can affect soil biogeochemistry, but their combined effects are not well understood. We examined the effects of water and N amendments and forest thinning and burning on soil N pools and fluxes in ponderosa pine forests near Flagstaff, Arizona (USA). Using a […]
1. Ecological restoration often involves returning ecosystem structure to some predisturbance reference state, but ecosystem function must also recover if restoration efforts are to be self-sustaining over the long term. In the south-western United States, ponderosa pine forest structure was altered by disruption of the fire regime following Euro-American settlement. […]
Forest ecosystems assimilate more CO2 from the atmosphere and store more carbon in woody biomass than most nonforest ecosystems, indicating strong potential for afforestation to serve as a carbon management tool. However, converting grasslands to forests could affect ecosystem–atmosphere exchanges of other greenhouse gases, such as nitrous oxide and methane […]
The linkages between fluvial geomorphology and aquatic ecosystems are commonly conceptualized as a one-way causal chain in which geomorphic processes create the physical template for ecological dynamics. In streams with a travertine step-pool morphology, however, biotic processes strongly influence the formation and growth of travertine dams, creating the potential for […]
Management of forests for carbon uptake is an important tool in the effort to slow the increase in atmospheric CO2 and global warming. However, some current policies governing forest carbon credits actually promote avoidable CO2 release and punish actions that would increase long-term carbon storage. In fire-prone forests, management that […]
This study reports the aboveground biomass response of a fire-regenerated Florida scrub-oak ecosystem exposed to elevated CO2 (1996–2007), from emergence after fire through canopy closure. Eleven years exposure to elevated CO2 caused a 67% increase in aboveground shoot biomass. Growth stimulation was sustained throughout the experiment; although there was significant […]
Soil is the largest reservoir of organic carbon (C) in the terrestrial biosphere and soil C has a relatively long mean residence time. Rising atmospheric carbon dioxide (CO2) concentrations generally increase plant growth and C input to soil, suggesting that soil might help mitigate atmospheric CO2 rise and global warming. […]
A scrub-oak woodland has maintained higher aboveground biomass accumulation after 11 years of atmospheric CO2 enrichment (ambient +350 μmol CO2 mol−1), despite the expectation of strong nitrogen (N) limitation at the site. We hypothesized that changes in plant available N and exploitation of deep sources of inorganic N in soils have sustained greater […]
The effects of elevated CO2 on plant growth and insect herbivory have been frequently investigated over the past 20 years. Most studies have shown an increase in plant growth, a decrease in plant nitrogen concentration, an increase in plant secondary metabolites and a decrease in herbivory. However, such studies have […]