Biomass burning impacts vegetation dynamics, biogeochemical cycling, atmospheric chemistry, and climate, with sometimes deleterious socio-economic impacts. Under future climate projections it is often expected that the risk of wildfires will increase. Our ability to predict the magnitude and geographic pattern of future fire impacts rests on our ability to model...
Fire is a major disturbance process in many forests. Long-term studies of the biogeochemical effects of fires, especially on soils, are very rare.
Consequently, long-term effects of fire on soils are often hypothesized from
short-term effects. In a chronosequence study, I studied 24 western Cascades
(Oregon) forest stands thought to...
A large amount of organic carbon is stored in high-latitude soils. A substantial proportion of this carbon stock is vulnerable and may decompose rapidly due to temperature increases that are already greater than the global average. It is therefore crucial to quantify and understand carbon exchange between the atmosphere and...
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combined with bioclimatic limits (Hickler
et al., 2004; Wramneby et al., 2008). Bioclimatic conditions
Large amount of organic carbon is stored in high latitude soils. A substantial proportion of this carbon stock is vulnerable and may decompose rapidly due to temperature increases that are already greater than the global average. It is therefore crucial to quantify and understand carbon exchange between the atmosphere and...
Full Text:
based on plant phenological
and physiognomical features combined with bioclimatic limits (Hickler et al
Successful crop production depends initially on the availability of high-quality seed. By 2050 global climate change will have influenced crop yields, but will these changes affect seed quality? The present review examines the effects of elevated carbon dioxide (CO₂) and temperature during seed production on three seed quality components: seed...
Forests play an integral role in the global carbon cycle, regulating the atmospheric CO₂ concentration by sequestering nearly one third of anthropogenic carbon emissions and storing carbon for centuries. Forest ecosystems are integrated into the culture, ecology, and economy of western North America, supporting wildlife habitat, local economies, recreation, and...
Loss of biodiversity due to the effects of climate and land-use change may have implications for pollination services. Disruption to phenological synchronicity or a reduction in the overlap in species distributions of plants and their pollinators may reduce floral resources to pollinators, forcing them to move farther distances. If pollinators...
The Earth’s surface is experiencing unprecedented change. Humanity’s growing population, expanding land-use footprint, and increasing global emissions of atmospheric greenhouse gases affect a vast number of species on Earth and the functioning of virtually all ecosystems. Given the vital interactions and feedbacks between the Earth’s land surface and climate, measurements...
In order to investigate potential climate impacts on landscape-scale ecosystem processes, I implemented a dynamic general vegetation model (DGVM) over a large domain in northern California and western Nevada on a rectangular grid of ca. 800-meter spatial resolution. I used 100 years of observed, monthly climate and nine future climate...
Landscape fire succession models (LFSMs) predict spatially–explicit interactions between vegetation
succession and disturbance, but these models have yet to fully integrate ungulate herbivory as a driver of
their processes. We modified a complex LFSM, FireBGCv2, to include a multi-species herbivory module,
GrazeBGC. The system is novel in that it explicitly...