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nteractions between plants and insects encompass half of all ecological relationships (Strong et al. 1984), yet natural constraints keep most species from undergoing wide-scale population eruptions. Understanding the dynamics of eruptive species can provide valuable insights into fundamental ecological processes such as ecosystem disturbance, multitrophic(More)
Millions of trees killed by bark beetles in western North America have raised concerns about subsequent wildfire, but studies have reported a range of conclusions, often seemingly contradictory, about effects on fuels and wildfire. In this study, we reviewed and synthesized the published literature on modifications to fuels and fire characteristics(More)
[1] Disturbance processes of various types substantially modify ecosystem carbon dynamics both temporally and spatially, and constitute a fundamental part of larger landscape-level dynamics. Forests typically lose carbon for several years to several decades following severe disturbance, but our understanding of the duration and dynamics of post-disturbance(More)
[1] Downwelling surface solar radiation is an important input to ecosystem models, and global models require spatially extensive data sets that vary interannually to capture effects that potentially drive changes in ecosystem function. In this paper, I describe and compare solar radiation data sets from two representative sources, National Centers for(More)
Climatic change is likely to affect Pacific Northwest (PNW) forests in several important ways. In this paper, we address the role of climate in four forest ecosystem processes and project the effects of future climatic change on these processes across Washington State. First, we relate Douglas-fir growth to climatic limitation and suggest that where(More)
[1] Insect outbreaks are significant disturbances in forests of the western United States, with infestation comparable in area to fire. Outbreaks of mountain pine beetle (Dendroctonus ponderosae Hopkins) require life cycles of one year with synchronous emergence of adults from host trees at an appropriate time of year (termed ''adaptive seasonality'') to(More)
About one-third of North America is forested. These forests are of incalculable value to human society in terms of harvested resources and ecosystem services and are sensitive to disturbance regimes. Epidemics of forest insects and diseases are the dominant sources of disturbance to North American forests. Here we review current understanding of climatic(More)
[1] Net primary productivity (NPP) in North America was computed for the years 1982 –1998 using the Carnegie-Ames-Stanford approach (CASA) carbon cycle model. CASA was driven by a new, corrected satellite record of the normalized difference vegetation index at 8-km spatial resolution. Regional trends in the 17-year NPP record varied substantially across the(More)
[1] Forest disturbances greatly alter the carbon cycle at various spatial and temporal scales. It is critical to understand disturbance regimes and their impacts to better quantify regional and global carbon dynamics. This review of the status and major challenges in representing the impacts of disturbances in modeling the carbon dynamics across North(More)
[1] We used a new 17-year, high spatial resolution satellite record and a carbon cycle model to explore how changing net primary productivity (NPP) contributed to a proposed carbon (C) sink in North America. We found a small but significant increase in NPP, 0.03 Pg C yr À2 or 8% over 17 years, that could explain a substantial fraction of the C sink. The(More)