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- Leaf and stem functional traits related to plant water relations were studied for six congeneric species pairs, each composed of one tree species typical of savanna habitats and another typical of adjacent forest habitats, to determine whether there were intrinsic differences in plant hydraulics between these two functional types. Only individuals growing in savanna habitats were studied. Most stem traits, including wood density, the xylem water potential at 50-percent loss of hydraulic conductivity, sapwood area specific conductivity, and leaf area specific conductivity did not differ...AuthorsGuang You Hao, William A. Hoffmann, Fabian G. Scholz, Sandra J. Bucci, Frederick Meinzer, Augusto C. Franco, Kun Fang Cao, Guillermo GoldsteinSourceOecologia. 155: 405-415Year2008
- I volunteered to review this book with a preconceived notion of the term "environment" as forests, streams, oceans, glaciers, deserts, houses, etc. The first four chapters thus took me somewhat aback: "Imaging complex nutrient dynamics in mycelial networks," "Natural history of the fungal hypha: how Woronin bodies suppolil: a multicellular lifestyle," "Environmental sensing and the filamentous fungal lifestyle," and "Mathematical modelling of the form and function of fungal mycelia." Adjusting my vision to the reality that fungi are always in an environment, and environments may range from...AuthorsJim TrappeKeywordsSourceInoculum, Vol. 59, No. 4, p. 70-71Year2008
- Black spruce (Picea mariana (Mill) B.S.P) is the dominant forest cover type in interior Alaska and is prone to frequent, stand-replacing wildfires. Through impacts on tree recruitment, the degree of fire consumption of soil organic layers can act as an important determinant of whether black spruce forests regenerate to a forest composition similar to the prefire forest, or to a new forest composition dominated by deciduous hardwoods. Here we present a simple, rule-based framework for predicting fire-initiated changes in forest cover within Alaska's black spruce forests. Four components are...AuthorsJill F. Johnstone, Teresa Hollingsworth, F. Stuart ChapinKeywordsSourceGen. Tech. Rep. PNW-GTR-767. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 37 p.Year2008
- For much of the last century, the connection between national forests and many rural forest communities, especially in the Pacific Northwest, was defined by timber-related employment. Assumptions about the economic dependence of forest communities on federal timber prompted the Forest Service to make community stability a matter of agency policy. But the relationship between forests and communities has changed, particularly over the last 25 years with declining timber harvests on federal land. Without question, declines in timber production and other resource-base industries have adversely...AuthorsSussanne MalekiKeywordsSourceScience Update 18. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 12 p.Year2008
- This report uses data from a network of forest inventory plots sampled at two points in time, annual aerial insect and disease surveys, and specialized pest damage surveys to quantify the incidence and impact of insects, diseases, and other damaging agents on Oregon's forests. The number and volume of trees damaged or killed by various agents is summarized. Differences in the frequency and severity of damaging agents between various ownership categories and geographic regions of the state are investigated.AuthorsPaul A. DunhamKeywordsSourceResour. Bull. PNW-RB-257. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 89 p.Year2008
- The concept of management studies--implemented by managers as normal business to meet priority learning needs--is applied to a priority regional question: how to manage after a large wildfire to better meet preexisting or new societal needs. Because of a lack of knowledge and studies, deciding how to manage after wildfire is fraught with uncertainty. We have developed the concept of a network of management studies with a rigorous experimental design to fill this need. Details on how to implement this generic landscape-scale management study on future wildfire areas are provided. We...AuthorsB.T. Bormann, J.A. Laurence, K. Shimamoto, J. Thrailkill, J. Lehmkuhl, G. Reeves, A. Markus, D.W. Peterson, E. ForsmanKeywordsSourceGen. Tech. Rep. PNW-GTR-777. Portland OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 27 p.Year2008
- Managed ecosystems experience vulnerabilities when ecological resilience declines and key flows of ecosystem services become depleted or lost. Drivers of vulnerability often include local management actions in conjunction with other external, larger scale factors. To translate these concepts to management applications, we developed a conceptual model of feedbacks linking the provision of ecosystem services, their use by society, and anthropogenic change. From this model we derived a method to integrate existing geodata at relevant scales and in locally meaningful ways to provide decision...AuthorsColin M. Beier, Trista Patterson, F. Stuart Chapin IIIKeywordsSourceEcosystems 11: 923-938Year2008
- This report highlights key findings from the most recent (2001-2005) data collected by the Pacific Northwest Forest Inventory and Analysis (PNW-FIA) Program across all ownerships in Oregon. We present basic resource information such as forest area, land use change, ownership, volume, biomass, and carbon sequestration; structure and function topics such as biodiversity, older forests, dead wood, and riparian forests; disturbance topics such as insects and diseases, fire, invasive plants, and air pollution; and information about the forest products industry in Oregon, including data on tree...AuthorsJoseph Donnegan, Sally Campbell, Dave AzumaKeywordsSourceGen. Tech. Rep. PNW-GTR-765. Portland, OR: U.S. Forest Service, Pacific Northwest Research Station. 186 p.Year2008
- This report highlights key findings from the most recent (2001-2005) data collected by the Forest Inventory and Analysis Program across all forest land in California. We summarize and interpret basic resource information such as forest area, ownership, volume, biomass, and carbon stocks; structure and function topics such as biodiversity, forest age, dead wood, and hardwood forests; disturbance topics such as insects and diseases, fire, invasive plants, and air pollution; and information about the forest products industry in California, including data on tree growth and mortality, removals...AuthorsGlenn Christensen, Sally J. Campbell, Jeremy S. FriedKeywordsSourceGen. Tech. Rep. PNW-GTR-763. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 183 p.Year2008
- Prior to the existence of the National Environmental Policy Act (NEPA), Forest Service district rangers had considerable latitude to make resource management decisions and execute management plans with relatively little encumbrance by documentation and process requirements. Today there appear to be differences not only in the district ranger population, but in the decisionmaking processes they use and how they adapt their management style to particular circumstances. Indepth interviews were conducted with 12 district rangers to obtain their experiences with project design and development,...AuthorsDonald G. MacGregor, David N. SeesholtzKeywordsSourceGen. Tech. Rep. PNW-GTR-766. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 27 p.Year2008