Science.gov

Sample records for forest products research

  1. University of Maine Integrated Forest Product Refinery (IFPR) Technology Research

    SciTech Connect

    Pendse, Hemant P.

    2010-11-23

    This project supported research on science and technology that forms a basis for integrated forest product refinery for co-production of chemicals, fuels and materials using existing forest products industry infrastructure. Clear systems view of an Integrated Forest Product Refinery (IFPR) allowed development of a compelling business case for a small scale technology demonstration in Old Town ME for co-production of biofuels using cellulosic sugars along with pulp for the new owners of the facility resulting in an active project on Integrated Bio-Refinery (IBR) at the Old Town Fuel & Fiber. Work on production of advanced materials from woody biomass has led to active projects in bioplastics and carbon nanofibers. A lease for 40,000 sq. ft. high-bay space has been obtained to establish a Technology Research Center for IFPR technology validation on industrially relevant scale. UMaine forest bioproducts research initiative that began in April 2006 has led to establishment of a formal research institute beginning in March 2010.

  2. Aboveground tree biomass on productive forest land in Alaska. Forest Service research paper

    SciTech Connect

    Yarie, J.; Mead, D.R.

    1982-08-01

    Total aboveground woody biomass of trees on forest land that can produce 1.4 cubic meters per hectare per year of industrial wood in Alaska is 1.33 billion metric tons green weight. The estimated energy value of the standing woody biomass is 11.9 x 10 Btu's. Statewide tables of biomass and energy values for softwoods, hardwoods, and species group are presented.

  3. Multidisciplinary Research on Canopy Photosynthetic Productivity in a Cool-Temperate Deciduous Broadleaf Forest in Japan

    NASA Astrophysics Data System (ADS)

    Muraoka, H.; Noda, H. M.; Saitoh, T. M.; Nagai, S.

    2014-12-01

    Forest canopy has crucial roles in regulating energy and material exchange between the atmosphere and terrestrial ecosystems and in ecological processes with respect to carbon cycle and growth in the ecosystems. Challenges to the canopy of tall forests for such research involve the access to the leaves for ecophysiological observations, responses of leaves to the changing environments from seconds to years, and up-scaling the leaf-level phenomena to canopy and landscape-levels. A long-term, multidisciplinary approach has been conducted in a cool-temperate deciduous broadleaf forest in Takayama site (ca. 1400m a.s.l.) in central Japan. This forest canopy is dominated by Quercus crispula and Betula ermanii. We have been focusing on the phenology of photosynthetic productivity from a single leaf to canopy, and to landscape level, by combining leaf ecophysiological research, optical observations by spectroradiometers and time-laps cameras with the aid of "Phenological Eyes Network (PEN)", and process-based modellings. The canopy-level photosynthesis is then compared with the micrometeorolgical observation of CO2 flux at the site. So far we have been clarifying that (1) inter-annual variations in seasonal growth rate and senescence rate of leaf photosynthetic capacity and canopy leaf area are largely responsible for the inter-annual change in forest photosynthesis, and (2) spectral vegetation indices such as enhanced vegetation index (EVI) and chlorophyll index (CCI) can be the indicator to observe the phenology of forest canopy photosynthesis. In addition to these efforts since 2003, we established an open-field warming experiment on the branches of the canopy trees, to investigate the possible influence of temperature increase on leaf photosynthetic and optical properties and then to examine whether the optical satellite remote sensing can detect the changes in photosynthetic capacity and phenology by ongoing global warming.

  4. Forest Products Industry Technology Roadmap

    SciTech Connect

    none,

    2010-04-01

    This document describes the forest products industry's research and development priorities. The original technology roadmap published by the industry in 1999 and was most recently updated in April 2010.

  5. USDA Forest Service wetlands research

    SciTech Connect

    Bartuska, A.M. )

    1993-05-01

    Wetland and riparian systems play a major role in flood control, water quality, and food chain support. Timber production, fisheries, and recreation vie economically as primary uses of forested wetlands. This article reviews current Forest Service research in the Intermountain Region, North Central Region, Northeast Region, Pacific Northwest Region, Rocky Mountain Region, and Southern Region. Future research areas are discussed: ecosystem processes, restoration and rehabilitation, management of the wetland resource, socioeconomic values, and landscape-scale links. 8 refs.

  6. Airborne forest fire research

    NASA Technical Reports Server (NTRS)

    Mattingly, G. S.

    1974-01-01

    The research relating to airborne fire fighting systems is reviewed to provide NASA/Langley Research Center with current information on the use of aircraft in forest fire operations, and to identify research requirements for future operations. A literature survey, interview of forest fire service personnel, analysis and synthesis of data from research reports and independent conclusions, and recommendations for future NASA-LRC programs are included.

  7. Study of production functions for modeling forest biomass: An area for research

    SciTech Connect

    Nautiyal, J.C. ); Belli, K.L. )

    1989-09-01

    The usefulness of production functions, mathematical descriptions of production processes, has long been recognized by economists in manufacturing industries, and more recently by agricultural scientists in the field of biological production. As increasing emphasis in forestry is placed on short-rotation, intensive crop management it would seem that foresters would also require production functions for rational timber management planning. These functions could be useful in a number of areas such as: crop tree growth prediction, control of stand development, economic analysis for decision-making purposes, and for determining the so-called elasticities of inputs and outputs. A very general functional form that may be appropriate for the development of forestry models is the transcendental logarithmic, or translog, function. Unfortunately, at this time, sufficiently detailed data do not seem to be available for any tree species to estimate a production function that could make sophisticated intensive forest management possible.

  8. 78 FR 22225 - Solicitation of Input From Stakeholders Regarding the Integrated Forest Products Research Program

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-15

    ... Research (FPR) program and specifically design a response to current and emerging wood utilization issues... the U.S. wood products industry. Specifically, it addresses utilization needs of hardwood, southern... focused on creating new and improved wood uses and value-added products. Eligibility for the FPR is...

  9. Southern pulpwood harvesting productivity and cost changes between 1979 and 1987. Forest Service research paper

    SciTech Connect

    Carter, D.R.; Cubbage, F.W.; Stokes, B.J.; Jakes, P.J.

    1994-05-16

    The Southern U.S. pulpwood harvesting industry experienced substantial changes in productivity and logging costs from 1979 to 1987. The research measures physical and economic changes in southern timber harvesting and the degree of industry shifting between different levels of harvesting mechanization.

  10. Mixed plantations of eucalyptus and leguminous trees enhance biomass production. Forest Service research paper (Final)

    SciTech Connect

    DeBell, D.S.; Whitesell, C.D.; Schubert, T.H.

    1985-07-01

    Two Eucalyptus species--E. Saligna and E. grandis--are especially favored in Hawaii for wood, fiber, and fuel production because of their quick growth and high yields. Their growth is limited, however, on many sites by low levels of available nitrogen. Supplemental nitrogen can be provided by nitrogen-fixing plants, such as legumes. A test was conducted to determine whether planting two leguminous species--Acacia melanoxylon and Albizia falcataria Fosberg--could increase biomass production. Total biomass production was much greater in the mixed-species plantations than in the pure Eucalyptus plantation.

  11. Product recovery of ponderosa pine in Arizona and New Mexico. Forest Service research paper

    SciTech Connect

    Fahey, T.D.; Ayer Sachet, J.K.

    1993-11-01

    A mill recovery of ponderosa pine in Arizona and New Mexico showed wide variation in quality within the resource. Lumber grade ranged widely by log grade and diameter, with a major difference within grade 5 logs between old growth and young growth. Old growth produced mostly Shop and Selects grades of lumber while young growth produced mostly Dimension grades of lumber; small-diameter young growth developed severe problems of warpage. Log grades separated logs into distinct value classes, and separating young-growth timber (as an additional grade) allowed better segregation of logs by product type and expected value.

  12. [Research advances in forest soil respiration].

    PubMed

    Luan, Junwei; Xiang, Chenghua; Luo, Zongshi; Gong, Yuanbo

    2006-12-01

    Among the methods of measuring forest soil respiration, infrared CO2 analysis is the optimal one so far. Comparing with empirical model, the process-based model in simulating the production and transportation of soil CO2 has the advantage of considering the biological and physical processes of soil respiration. Generally, soil respiration is positively correlated with soil temperature and moisture, but there are still many uncertainties about the relationships between soil respiration and forest management activities such as firing, cutting, and fertilization. The relationships of soil respiration with vegetation type and soil microbial biomass, as well as the spatial heterogeneity of soil respiration, are the hotspots in recent researches. Some issues and future development in forest soil respiration research were discussed in this paper.

  13. 29 CFR 780.159 - Forest products.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Other Unlisted Practices Which May Be within Section 3(f) § 780.159 Forest products. Trees grown in forests and the lumber derived therefrom are not agricultural or horticultural commodities, for the... 29 Labor 3 2013-07-01 2013-07-01 false Forest products. 780.159 Section 780.159 Labor...

  14. 29 CFR 780.159 - Forest products.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Other Unlisted Practices Which May Be within Section 3(f) § 780.159 Forest products. Trees grown in forests and the lumber derived therefrom are not agricultural or horticultural commodities, for the... 29 Labor 3 2014-07-01 2014-07-01 false Forest products. 780.159 Section 780.159 Labor...

  15. 29 CFR 780.115 - Forest products.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Agricultural Or Horticultural Commodities § 780.115 Forest products. Trees grown in forests and the lumber derived therefrom are not “agricultural or horticultural commodities.” Christmas trees, whether wild or... 29 Labor 3 2014-07-01 2014-07-01 false Forest products. 780.115 Section 780.115 Labor...

  16. 29 CFR 780.115 - Forest products.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Agricultural Or Horticultural Commodities § 780.115 Forest products. Trees grown in forests and the lumber derived therefrom are not “agricultural or horticultural commodities.” Christmas trees, whether wild or... 29 Labor 3 2011-07-01 2011-07-01 false Forest products. 780.115 Section 780.115 Labor...

  17. 29 CFR 780.159 - Forest products.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Other Unlisted Practices Which May Be within Section 3(f) § 780.159 Forest products. Trees grown in forests and the lumber derived therefrom are not agricultural or horticultural commodities, for the... 29 Labor 3 2010-07-01 2010-07-01 false Forest products. 780.159 Section 780.159 Labor...

  18. 29 CFR 780.115 - Forest products.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Agricultural Or Horticultural Commodities § 780.115 Forest products. Trees grown in forests and the lumber derived therefrom are not “agricultural or horticultural commodities.” Christmas trees, whether wild or... 29 Labor 3 2012-07-01 2012-07-01 false Forest products. 780.115 Section 780.115 Labor...

  19. 29 CFR 780.159 - Forest products.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Other Unlisted Practices Which May Be within Section 3(f) § 780.159 Forest products. Trees grown in forests and the lumber derived therefrom are not agricultural or horticultural commodities, for the... 29 Labor 3 2012-07-01 2012-07-01 false Forest products. 780.159 Section 780.159 Labor...

  20. 29 CFR 780.159 - Forest products.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Other Unlisted Practices Which May Be within Section 3(f) § 780.159 Forest products. Trees grown in forests and the lumber derived therefrom are not agricultural or horticultural commodities, for the... 29 Labor 3 2011-07-01 2011-07-01 false Forest products. 780.159 Section 780.159 Labor...

  1. 29 CFR 780.115 - Forest products.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Agricultural Or Horticultural Commodities § 780.115 Forest products. Trees grown in forests and the lumber derived therefrom are not “agricultural or horticultural commodities.” Christmas trees, whether wild or... 29 Labor 3 2013-07-01 2013-07-01 false Forest products. 780.115 Section 780.115 Labor...

  2. 29 CFR 780.115 - Forest products.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Agricultural Or Horticultural Commodities § 780.115 Forest products. Trees grown in forests and the lumber derived therefrom are not “agricultural or horticultural commodities.” Christmas trees, whether wild or... 29 Labor 3 2010-07-01 2010-07-01 false Forest products. 780.115 Section 780.115 Labor...

  3. Researching the Rain Forest.

    ERIC Educational Resources Information Center

    Chazdon, Robin L.

    1995-01-01

    An autobiography of a female ecologist working in the Costa Rican rainforest is provided as an inspiration for girls. The scientist briefly tells her life story and describes her research activities. (LZ)

  4. Method of determining forest production from remotely sensed forest parameters

    DOEpatents

    Corey, J.C.; Mackey, H.E. Jr.

    1987-08-31

    A method of determining forest production entirely from remotely sensed data in which remotely sensed multispectral scanner (MSS) data on forest 5 composition is combined with remotely sensed radar imaging data on forest stand biophysical parameters to provide a measure of forest production. A high correlation has been found to exist between the remotely sensed radar imaging data and on site measurements of biophysical 10 parameters such as stand height, diameter at breast height, total tree height, mean area per tree, and timber stand volume.

  5. 36 CFR 223.216 - Special Forest Products definitions.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 36 Parks, Forests, and Public Property 2 2013-07-01 2013-07-01 false Special Forest Products definitions. 223.216 Section 223.216 Parks, Forests, and Public Property FOREST SERVICE, DEPARTMENT OF AGRICULTURE SALE AND DISPOSAL OF NATIONAL FOREST SYSTEM TIMBER, SPECIAL FOREST PRODUCTS, AND FOREST...

  6. 36 CFR 223.216 - Special Forest Products definitions.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 36 Parks, Forests, and Public Property 2 2011-07-01 2011-07-01 false Special Forest Products definitions. 223.216 Section 223.216 Parks, Forests, and Public Property FOREST SERVICE, DEPARTMENT OF AGRICULTURE SALE AND DISPOSAL OF NATIONAL FOREST SYSTEM TIMBER, SPECIAL FOREST PRODUCTS, AND FOREST...

  7. 36 CFR 223.216 - Special Forest Products definitions.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 36 Parks, Forests, and Public Property 2 2014-07-01 2014-07-01 false Special Forest Products definitions. 223.216 Section 223.216 Parks, Forests, and Public Property FOREST SERVICE, DEPARTMENT OF AGRICULTURE SALE AND DISPOSAL OF NATIONAL FOREST SYSTEM TIMBER, SPECIAL FOREST PRODUCTS, AND FOREST...

  8. Forest production for tropical America. Agriculture handbook

    SciTech Connect

    Wadsworth, F.H.

    1997-12-01

    This book is concerned primarily with wood production. Without the direct economic returns possible therefrom, the other, less tangible benefits that accrue from forests are in jeopardy in the face of developmental pressures driven by more attractive direct financial incentives. Nevertheless, multiple benefits from forests are inseparable, so the goal should be to make forest productive for all purposes. Forest production, then, as here defined refers to all the values of forests, including those primarily esthetic. The text emphasizes two vital relations. One is that forestry is ecological. Forest managers must be oriented to accept ecological information fundamental to goals and practices. A rift between the two disciplines that exists elsewhere must not intensify in tropical America. Forest production is forestry, not ecology, but intimacy between the two disciplines is mutually vital. The second relation emphasized in the book is that in productive forest management the animal component is as crucial as the plants, The value of animals to forest ecosystems goes far beyond their physical attraction.

  9. Classifying forest productivity at different scales

    SciTech Connect

    Graham, R.L.

    1991-01-01

    Spatial scale is an important consideration when evaluating, using, or constructing forest productivity classifications. First, the factors which dominate spatial variability in forest productivity are scale dependent. For example, within a stand, spatial variability in productivity is dominated by microsite differences; within a national forest such as the Cherokee National Forest, spatial variability is dominated by topography and land-use history (e.g., years since harvest); within a large region such as the southeast, spatial variability is dominated by climatic patterns. Second, classifications developed at different spatial scales are often used for different purposes. For example, stand-level classifications are often keys or rules used in the field to judge the quality or potential of a site. National-forest classifications are often presented as maps or tables and may be used in forest land planning. Regional classifications may be maps or tables and may be used to quantify or predict resource availability. These scale-related differences in controlling factors and purposes will affect both the methods and the data used to develop classifications. In this paper, I will illustrate these points by describing and comparing three forest productivity classifications, each developed for a specific purpose at a specific scale. My objective is not to argue for or against any of these particular classifications but rather to heighten awareness of the critical role that spatial scale plays in the use and development of forest productivity classifications. 8 refs., 2 figs., 1 tab.

  10. Forest products in the global economy

    SciTech Connect

    Hayter, R.

    1987-01-01

    The various industries which comprise the forest product sector - most importantly timber, wood pulp and newsprint - are significant elements on the global economy. While world production and trade remain concentrated in the industrialized world many Third World countries have invested in forest products and these countries will play an important role in the future. This book presents a comprehensive survey of forest product manufacturing and trade throughout the world. It analyses the forest resource policies of producer countries and outlines output levels and growth rates. It examines world patterns of trade including both demand and supply and temperate and tropical producers. It considers the industry itself, its organisation, ownership and control, the technology employed and technology transfer. The book covers all the major countries involved in the industry including the USA, Canada, Japan, the Soviet bloc, South East Asia, West Africa and Northern Europe. It concludes with an assessment of likely future trends. CONTENTS. Introduction, origins and evolution, the forest resource, distribution, ownership and utilization, world patterns of production and trade, world patterns of demand, organization, technology and location, the coniferous belt producers, the tropical producers, the international transfer of technology in forest products, forest products in third world development, and future prospects.

  11. Influence of disturbance on temperate forest productivity

    USGS Publications Warehouse

    Peters, Emily B.; Wythers, Kirk R.; Bradford, John B.; Reich, Peter B.

    2013-01-01

    Climate, tree species traits, and soil fertility are key controls on forest productivity. However, in most forest ecosystems, natural and human disturbances, such as wind throw, fire, and harvest, can also exert important and lasting direct and indirect influence over productivity. We used an ecosystem model, PnET-CN, to examine how disturbance type, intensity, and frequency influence net primary production (NPP) across a range of forest types from Minnesota and Wisconsin, USA. We assessed the importance of past disturbances on NPP, net N mineralization, foliar N, and leaf area index at 107 forest stands of differing types (aspen, jack pine, northern hardwood, black spruce) and disturbance history (fire, harvest) by comparing model simulations with observations. The model reasonably predicted differences among forest types in productivity, foliar N, leaf area index, and net N mineralization. Model simulations that included past disturbances minimally improved predictions compared to simulations without disturbance, suggesting the legacy of past disturbances played a minor role in influencing current forest productivity rates. Modeled NPP was more sensitive to the intensity of soil removal during a disturbance than the fraction of stand mortality or wood removal. Increasing crown fire frequency resulted in lower NPP, particularly for conifer forest types with longer leaf life spans and longer recovery times. These findings suggest that, over long time periods, moderate frequency disturbances are a relatively less important control on productivity than climate, soil, and species traits.

  12. The Cooperative Forest Ecosystem Research Program

    USGS Publications Warehouse

    ,

    2002-01-01

    Changes in priorities for forest management on federal and state lands in the Pacific Northwest have raised many questions about the best ways to manage young-forest stands, riparian areas, and forest landscapes. The Cooperative Forest Ecosystem Research (CFER) Program draws together scientists and managers from the U.S. Geological Survey, Bureau of Land Management, Oregon Department of Forestry, and Oregon State University to find science-based answers to these questions. Managers, researchers, and decisionmakers, working within the CFER program, are helping develop and disseminate the knowledge needed to carry out ecosystem-based management successfully in the Pacific Northwest.

  13. Forest products industry of the future: Building a sustainable technology advantage for America`s forest products industry

    SciTech Connect

    1999-02-01

    The US forest, wood, and paper industry ranks as one of the most competitive forest products industries in the world. With annual shipments valued at nearly $267 billion, it employs over 1.3 million people and is currently among the top 10 manufacturing employers in 46 out of 50 states. Retaining this leadership position will depend largely on the industry`s success in developing and using advanced technologies. These technologies will enable manufacturing plants and forestry enterprises to maximize energy and materials efficiency and reduce waste and emissions, while producing high-quality, competitively priced wood and paper products. In a unique partnership, leaders in the forest products industry have teamed with the US Department of Energy`s Office of Industrial Technologies (OIT) to encourage cooperative research efforts that will help position the US forest products industry for continuing prosperity while advancing national energy efficiency and environmental goals.

  14. Productivity of forest birds at Hakalau Forest NWR

    USGS Publications Warehouse

    Paxton, Eben; Cummins, George C; Kendall, Steven J.

    2014-01-01

    Hawai‘i has some of the most endangered avian species in the world, which face numerous threats from habitat loss, disease, climate change, and introduced species. This report details the results of a two-year productivity study of all forest bird species at Hakalau National Wildlife Refuge, Hawai‘i Island. We found and monitored nests from seven native species and three common non-native species of forest birds at three sites across the refuge. In addition to gathering important baseline information on productivity of forest birds, we examined differences in productivity between years, sites, and as a function of nest height. The weather differed greatly between the two years, with much more rain occurring in 2014. The daily survival rate (DSR) of nests was found to have an inverse relationship with the amount of rainfall, and accordingly was much lower in 2014 compared to 2013. Nest success was lower at a regenerating forest site compared with mature rainforest, indicating negative environmental factors affecting nest success may be exacerbated in reforested areas which have lower canopies. Nest success was also impacted by nest height, with a positive relationship in the drier 2013, and a negative relationship in 2014 for the canopy nesting honeycreepers. The large difference in weather and DSR between years illustrates the need for long term demographic studies that can capture the vital rates of this community of birds.

  15. 36 CFR 223.277 - Forest botanical products definition.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ..., transplants, tree sap, and wildflowers. Forest botanical products are not animals, animal parts, Christmas... 36 Parks, Forests, and Public Property 2 2011-07-01 2011-07-01 false Forest botanical products definition. 223.277 Section 223.277 Parks, Forests, and Public Property FOREST SERVICE, DEPARTMENT...

  16. 36 CFR 223.277 - Forest botanical products definition.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ..., transplants, tree sap, and wildflowers. Forest botanical products are not animals, animal parts, Christmas... 36 Parks, Forests, and Public Property 2 2014-07-01 2014-07-01 false Forest botanical products definition. 223.277 Section 223.277 Parks, Forests, and Public Property FOREST SERVICE, DEPARTMENT...

  17. 36 CFR 223.277 - Forest botanical products definition.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ..., transplants, tree sap, and wildflowers. Forest botanical products are not animals, animal parts, Christmas... 36 Parks, Forests, and Public Property 2 2013-07-01 2013-07-01 false Forest botanical products definition. 223.277 Section 223.277 Parks, Forests, and Public Property FOREST SERVICE, DEPARTMENT...

  18. 36 CFR 223.277 - Forest botanical products definition.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ..., transplants, tree sap, and wildflowers. Forest botanical products are not animals, animal parts, Christmas... 36 Parks, Forests, and Public Property 2 2012-07-01 2012-07-01 false Forest botanical products definition. 223.277 Section 223.277 Parks, Forests, and Public Property FOREST SERVICE, DEPARTMENT...

  19. Minnesota timber industry: An assessment of timber product output and use, 1990. Forest Service resource bulletin

    SciTech Connect

    Hackett, R.L.; Dahlman, R.A.

    1993-01-01

    The bulletin includes recent Minnesota forest industry trends and report the results of a detailed study of forest industry, industrial roundwood production, and associated primary mill wood and bark residue in Minnesota in 1990. Such detailed information is necessary for intelligent planning and decisionmaking in wood procurement, forest resource management, and forest industry development. Likewise, researchers need current forest industry and industrial roundwood information for planning projects.

  20. Overview of Contemporary Issues of Forest Research and Management in China

    NASA Astrophysics Data System (ADS)

    He, Hong S.; Shifley, Stephen R.; Thompson, Frank R.

    2011-12-01

    With 207 million ha of forest covering 22% of its land area, China ranks fifth in the world in forest area. Rapid economic growth, climate change, and forest disturbances pose new, complex challenges for forest research and management. Progress in meeting these challenges is relevant beyond China, because China's forests represent 34% of Asia's forests and 5% of the worlds' forests. To provide a broader understanding of these management challenges and of research and policies that address them, we organized this special issue on contemporary forest research and management issues in China. At the national level, papers review major forest types and the evolution of sustainable forestry, the development of China's forest-certification efforts, the establishment of a forest inventory system, and achievements and challenges in insect pest control in China. Papers focused on Northern China address historical, social, and political factors that have shaped the region's forests; the use of forest landscape models to assess how forest management can achieve multiple objectives; and analysis and modeling of fuels and fire behavior. Papers addressing Central and South China describe the "Grain for Green" program, which converts low productivity cropland to grassland and woodland to address erosion and soil carbon sequestration; the potential effects of climate change on CO2 efflux and soil respiration; and relationships between climate and net primary productivity. China shares many forest management and research issues with other countries, but in other cases China's capacity to respond to forest management challenges is unique and bears watching by the rest of the world.

  1. 75 FR 64617 - National Forest Products Week, 2010

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-20

    ... Documents#0;#0; ] Proclamation 8587 of October 15, 2010 National Forest Products Week, 2010 By the President... anniversary of National Forest Products Week, we recognize the enduring value of forests as sustainable... we write on. National Forest Products Week draws attention to these invaluable resources, and to...

  2. 36 CFR 261.6 - Timber and other forest products.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... or otherwise damaging any timber, tree, or other forest product, except as authorized by a special... otherwise identifying any tree or other forest product in a manner similar to that employed by forest officers to mark or designate a tree or any other forest product for cutting or removal. (e)...

  3. 36 CFR 261.6 - Timber and other forest products.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... or otherwise damaging any timber, tree, or other forest product, except as authorized by a special... otherwise identifying any tree or other forest product in a manner similar to that employed by forest officers to mark or designate a tree or any other forest product for cutting or removal. (e)...

  4. 36 CFR 261.6 - Timber and other forest products.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... or otherwise damaging any timber, tree, or other forest product, except as authorized by a special... otherwise identifying any tree or other forest product in a manner similar to that employed by forest officers to mark or designate a tree or any other forest product for cutting or removal. (e)...

  5. 36 CFR 261.6 - Timber and other forest products.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... or otherwise damaging any timber, tree, or other forest product, except as authorized by a special... otherwise identifying any tree or other forest product in a manner similar to that employed by forest officers to mark or designate a tree or any other forest product for cutting or removal. (e)...

  6. 25 CFR 163.16 - Forest product sales without advertisement.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false Forest product sales without advertisement. 163.16... FORESTRY REGULATIONS Forest Management and Operations § 163.16 Forest product sales without advertisement. (a) Sales of forest products may be made without advertisement to Indians or non-Indians with...

  7. Integrated Forest Products Refinery (IFPR)

    SciTech Connect

    van Heiningen, Adriaan R. P.

    2010-05-29

    about 1% (on pulp). By using the wet-end retention aid guar gum during the adsorption process at a charge of 0.5% on pulp the yield gain may be increased to about 5%. Unfortunately, most of this yield increase is lost during subsequent alkaline treatments in the pulp bleach plant. It was found that by performing the adsorption at alkaline conditions the adsorption loss during alkaline treatment in the bleach plant is mostly avoided. Thus a permanent adsorption yield of about 3 and 1.5% (on pulp) was obtained with addition of guar gum at a charge of 0.5 and 0.1% respectively during adsorption of GL hardwood extract on pre-extracted kraft pulp at optimal conditions of pH 11.5, 90 C for 60 minutes at 5% consistency. The beatability of the adsorbed kraft pulps was improved. Also, significant physical strength improvements were achieved. Further study is needed to determine whether the improvements in pulp yield and paper properties make this an economic IFPR concept. Application of the wood solids of a hot water extract of Acer rubrum wood strands as a substitute for polystyrene used for production of SMC maintained the water adsorption properties of the final product. Further work on the physical properties of the hemicellulose containing SMCs need to be completed to determine the potential of wood extracts for the production of partially renewable SMCs. The discovery of the “near-neutral” green liquor extraction process for hardwood was formed the basis for a commercial Integrated Biorefinery that will extract hemicelluloses from wood chips to make biofuels and other specialty chemicals. The pulp production process will be maintained as is proposed in the present researched IFBR concept. This Integrated Biorefinery will be constructed by Red Shield Acquisition LLC (RSA) at the Old Town kraft pulp mill in Maine. RSA in collaboration with the University of Maine will develop and commercialize the hemicellulose extraction process, the conversion of the hemicellulose

  8. Sustainable Harvest and marketing of rain forest products

    SciTech Connect

    Plotkin, M.J.; Famolare, L.M.

    1992-01-01

    The economics of nontimber rainforest products often make a strong case for forest protection and prevention of deforestation. This book contains 33 diverse papers falling into three catagories: tropical rainforests are underutilized sources of new plant products; increased use of tropical forest products should benefit human inhabitants of the rainforest; nontimber forest products many not be the panacea that some suggest.

  9. The importance of forest structure to biodiversity–productivity relationships

    PubMed Central

    Huth, Andreas

    2017-01-01

    While various relationships between productivity and biodiversity are found in forests, the processes underlying these relationships remain unclear and theory struggles to coherently explain them. In this work, we analyse diversity–productivity relationships through an examination of forest structure (described by basal area and tree height heterogeneity). We use a new modelling approach, called ‘forest factory’, which generates various forest stands and calculates their annual productivity (above-ground wood increment). Analysing approximately 300 000 forest stands, we find that mean forest productivity does not increase with species diversity. Instead forest structure emerges as the key variable. Similar patterns can be observed by analysing 5054 forest plots of the German National Forest Inventory. Furthermore, we group the forest stands into nine forest structure classes, in which we find increasing, decreasing, invariant and even bell-shaped relationships between productivity and diversity. In addition, we introduce a new index, called optimal species distribution, which describes the ratio of realized to the maximal possible productivity (by shuffling species identities). The optimal species distribution and forest structure indices explain the obtained productivity values quite well (R2 between 0.7 and 0.95), whereby the influence of these attributes varies within the nine forest structure classes. PMID:28280550

  10. 25 CFR 163.14 - Sale of forest products.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 25 Indians 1 2012-04-01 2011-04-01 true Sale of forest products. 163.14 Section 163.14 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER GENERAL FORESTRY REGULATIONS Forest Management and Operations § 163.14 Sale of forest products. (a) Consistent with the economic objectives...

  11. 25 CFR 163.14 - Sale of forest products.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 25 Indians 1 2013-04-01 2013-04-01 false Sale of forest products. 163.14 Section 163.14 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER GENERAL FORESTRY REGULATIONS Forest Management and Operations § 163.14 Sale of forest products. (a) Consistent with the economic objectives...

  12. 25 CFR 163.26 - Forest product harvesting permits.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 25 Indians 1 2011-04-01 2011-04-01 false Forest product harvesting permits. 163.26 Section 163.26 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER GENERAL FORESTRY REGULATIONS Forest Management and Operations § 163.26 Forest product harvesting permits. (a) Except as provided...

  13. 25 CFR 163.26 - Forest product harvesting permits.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 25 Indians 1 2014-04-01 2014-04-01 false Forest product harvesting permits. 163.26 Section 163.26 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER GENERAL FORESTRY REGULATIONS Forest Management and Operations § 163.26 Forest product harvesting permits. (a) Except as provided...

  14. 25 CFR 163.26 - Forest product harvesting permits.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 25 Indians 1 2013-04-01 2013-04-01 false Forest product harvesting permits. 163.26 Section 163.26 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER GENERAL FORESTRY REGULATIONS Forest Management and Operations § 163.26 Forest product harvesting permits. (a) Except as provided...

  15. 25 CFR 163.26 - Forest product harvesting permits.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 25 Indians 1 2012-04-01 2011-04-01 true Forest product harvesting permits. 163.26 Section 163.26 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER GENERAL FORESTRY REGULATIONS Forest Management and Operations § 163.26 Forest product harvesting permits. (a) Except as provided...

  16. 25 CFR 163.16 - Forest product sales without advertisement.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 25 Indians 1 2012-04-01 2011-04-01 true Forest product sales without advertisement. 163.16 Section 163.16 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER GENERAL FORESTRY REGULATIONS Forest Management and Operations § 163.16 Forest product sales without advertisement. (a) Sales...

  17. 25 CFR 163.14 - Sale of forest products.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 25 Indians 1 2014-04-01 2014-04-01 false Sale of forest products. 163.14 Section 163.14 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER GENERAL FORESTRY REGULATIONS Forest Management and Operations § 163.14 Sale of forest products. (a) Consistent with the economic objectives...

  18. 25 CFR 163.16 - Forest product sales without advertisement.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 25 Indians 1 2011-04-01 2011-04-01 false Forest product sales without advertisement. 163.16 Section 163.16 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER GENERAL FORESTRY REGULATIONS Forest Management and Operations § 163.16 Forest product sales without...

  19. 25 CFR 163.16 - Forest product sales without advertisement.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 25 Indians 1 2013-04-01 2013-04-01 false Forest product sales without advertisement. 163.16 Section 163.16 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER GENERAL FORESTRY REGULATIONS Forest Management and Operations § 163.16 Forest product sales without...

  20. 25 CFR 163.14 - Sale of forest products.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false Sale of forest products. 163.14 Section 163.14 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER GENERAL FORESTRY REGULATIONS Forest Management and Operations § 163.14 Sale of forest products. (a) Consistent with the economic objectives...

  1. 25 CFR 163.22 - Payment for forest products.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false Payment for forest products. 163.22 Section 163.22 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER GENERAL FORESTRY REGULATIONS Forest Management and Operations § 163.22 Payment for forest products. (a) The basis of...

  2. 25 CFR 163.22 - Payment for forest products.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 25 Indians 1 2013-04-01 2013-04-01 false Payment for forest products. 163.22 Section 163.22 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER GENERAL FORESTRY REGULATIONS Forest Management and Operations § 163.22 Payment for forest products. (a) The basis of...

  3. 25 CFR 163.16 - Forest product sales without advertisement.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 25 Indians 1 2014-04-01 2014-04-01 false Forest product sales without advertisement. 163.16 Section 163.16 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER GENERAL FORESTRY REGULATIONS Forest Management and Operations § 163.16 Forest product sales without...

  4. 25 CFR 163.26 - Forest product harvesting permits.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false Forest product harvesting permits. 163.26 Section 163.26 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER GENERAL FORESTRY REGULATIONS Forest Management and Operations § 163.26 Forest product harvesting permits. (a) Except as provided...

  5. 25 CFR 163.22 - Payment for forest products.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 25 Indians 1 2014-04-01 2014-04-01 false Payment for forest products. 163.22 Section 163.22 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER GENERAL FORESTRY REGULATIONS Forest Management and Operations § 163.22 Payment for forest products. (a) The basis of...

  6. 25 CFR 163.14 - Sale of forest products.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 25 Indians 1 2011-04-01 2011-04-01 false Sale of forest products. 163.14 Section 163.14 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER GENERAL FORESTRY REGULATIONS Forest Management and Operations § 163.14 Sale of forest products. (a) Consistent with the economic objectives...

  7. 25 CFR 163.22 - Payment for forest products.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 25 Indians 1 2012-04-01 2011-04-01 true Payment for forest products. 163.22 Section 163.22 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER GENERAL FORESTRY REGULATIONS Forest Management and Operations § 163.22 Payment for forest products. (a) The basis of volume determination...

  8. 25 CFR 163.22 - Payment for forest products.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 25 Indians 1 2011-04-01 2011-04-01 false Payment for forest products. 163.22 Section 163.22 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER GENERAL FORESTRY REGULATIONS Forest Management and Operations § 163.22 Payment for forest products. (a) The basis of...

  9. 76 FR 65097 - National Forest Products Week, 2011

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-20

    ... Documents#0;#0; ] Proclamation 8738 of October 14, 2011 National Forest Products Week, 2011 By the President... important part of our economy. During National Forest Products Week, we celebrate the value of our woodlands... forests, the Congress, by Public Law 86-753 (36 U.S.C. 123), as amended, has designated the week...

  10. 29 CFR 780.1015 - Other forest products.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... means any plant of the forest and includes, of course, deciduous plants as well. ... 29 Labor 3 2013-07-01 2013-07-01 false Other forest products. 780.1015 Section 780.1015 Labor... Provisions Under Section 13(d) Requirements for Exemption § 780.1015 Other forest products. The...

  11. 29 CFR 780.1015 - Other forest products.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... means any plant of the forest and includes, of course, deciduous plants as well. ... 29 Labor 3 2014-07-01 2014-07-01 false Other forest products. 780.1015 Section 780.1015 Labor... Provisions Under Section 13(d) Requirements for Exemption § 780.1015 Other forest products. The...

  12. 29 CFR 780.1015 - Other forest products.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... means any plant of the forest and includes, of course, deciduous plants as well. ... 29 Labor 3 2011-07-01 2011-07-01 false Other forest products. 780.1015 Section 780.1015 Labor... Provisions Under Section 13(d) Requirements for Exemption § 780.1015 Other forest products. The...

  13. 29 CFR 780.1015 - Other forest products.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... means any plant of the forest and includes, of course, deciduous plants as well. ... 29 Labor 3 2010-07-01 2010-07-01 false Other forest products. 780.1015 Section 780.1015 Labor... Provisions Under Section 13(d) Requirements for Exemption § 780.1015 Other forest products. The...

  14. 29 CFR 780.1015 - Other forest products.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... means any plant of the forest and includes, of course, deciduous plants as well. ... 29 Labor 3 2012-07-01 2012-07-01 false Other forest products. 780.1015 Section 780.1015 Labor... Provisions Under Section 13(d) Requirements for Exemption § 780.1015 Other forest products. The...

  15. Key canopy traits drive forest productivity

    PubMed Central

    Reich, Peter B.

    2012-01-01

    Quantifying the mechanistic links between carbon fluxes and forest canopy attributes will advance understanding of leaf-to-ecosystem scaling and its potential application to assessing terrestrial ecosystem metabolism. Important advances have been made, but prior studies that related carbon fluxes to multiple canopy traits are scarce. Herein, presenting data for 128 cold temperate and boreal forests across a regional gradient of 600 km and 5.4°C (from 2.4°C to 7.8°C) in mean annual temperature, I show that stand-scale productivity is a function of the capacity to harvest light (represented by leaf area index, LAI), and to biochemically fix carbon (represented by canopy nitrogen concentration, %N). In combination, LAI and canopy %N explain greater than 75 per cent of variation in above-ground net primary productivity among forests, expressed per year or per day of growing season. After accounting for growing season length and climate effects, less than 10 per cent of the variance remained unexplained. These results mirror similar relations of leaf-scale and canopy-scale (eddy covariance) maximum photosynthetic rates to LAI and %N. Collectively, these findings indicate that canopy structure and chemistry translate from instantaneous physiology to annual carbon fluxes. Given the increasing capacity to remotely sense canopy LAI, %N and phenology, these results support the idea that physiologically based scaling relations can be useful tools for global modelling. PMID:22279168

  16. Western hardwoods: Value-added research and demonstration program. Forest Service general technical report

    SciTech Connect

    Green, D.; von Segen, W.; Willits, S.

    1995-09-01

    Research results from the value-added research and demonstration program for western hardwoods are summarized in this report. The intent of the program was to enhance the economy of the Pacific Northwest by helping local communities and forest industries produce wood products more efficiently. Emphasis was given to value-added products and barriers to increased utilization. The program was coordinated by the Pacific Northwest Research Station, the Pacific Northwest region of State and Private Forestry, and the Forest Products Laboratory.

  17. Forest turnover rates follow global and regional patterns of productivity

    USGS Publications Warehouse

    Stephenson, N.L.; van Mantgem, P.J.

    2005-01-01

    Using a global database, we found that forest turnover rates (the average of tree mortality and recruitment rates) parallel broad-scale patterns of net primary productivity. First, forest turnover was higher in tropical than in temperate forests. Second, as recently demonstrated by others, Amazonian forest turnover was higher on fertile than infertile soils. Third, within temperate latitudes, turnover was highest in angiosperm forests, intermediate in mixed forests, and lowest in gymnosperm forests. Finally, within a single forest physiognomic type, turnover declined sharply with elevation (hence with temperature). These patterns of turnover in populations of trees are broadly similar to the patterns of turnover in populations of plant organs (leaves and roots) found in other studies. Our findings suggest a link between forest mass balance and the population dynamics of trees, and have implications for understanding and predicting the effects of environmental changes on forest structure and terrestrial carbon dynamics. ??2005 Blackwell Publishing Ltd/CNRS.

  18. Factors Influencing Productivity Change in the Forest Products Industry,

    DTIC Science & Technology

    1985-04-01

    substitution together with nonneutral technical progress" (p.179) Solow (1957) in a landmark study developed a method for estimating * technological change... Solow approach to measuring total factor productivity is the impli- 30 cit assumption of neutral technological change. In the case of the forest products...Three Mississippi Counties. Mississippi Agricultural Experiment Station Bulletin No. 713. Solow , R. M. 1959. Investment and Economic Growth: Some

  19. 76 FR 50715 - Information Collection; Forest Products Removal Permits and Contracts

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-16

    ... Forest Service Information Collection; Forest Products Removal Permits and Contracts AGENCY: Forest... Act of 1995, the Forest Service is seeking comments from all interested individuals and organizations on the extension with no revision of a currently approved information collection, Forest...

  20. Are forest disturbances amplifying or canceling out climate change-induced productivity changes in European forests?

    NASA Astrophysics Data System (ADS)

    Reyer, Christopher P. O.; Bathgate, Stephen; Blennow, Kristina; Borges, Jose G.; Bugmann, Harald; Delzon, Sylvain; Faias, Sonia P.; Garcia-Gonzalo, Jordi; Gardiner, Barry; Gonzalez-Olabarria, Jose Ramon; Gracia, Carlos; Guerra Hernández, Juan; Kellomäki, Seppo; Kramer, Koen; Lexer, Manfred J.; Lindner, Marcus; van der Maaten, Ernst; Maroschek, Michael; Muys, Bart; Nicoll, Bruce; Palahi, Marc; Palma, João HN; Paulo, Joana A.; Peltola, Heli; Pukkala, Timo; Rammer, Werner; Ray, Duncan; Sabaté, Santiago; Schelhaas, Mart-Jan; Seidl, Rupert; Temperli, Christian; Tomé, Margarida; Yousefpour, Rasoul; Zimmermann, Niklaus E.; Hanewinkel, Marc

    2017-03-01

    Recent studies projecting future climate change impacts on forests mainly consider either the effects of climate change on productivity or on disturbances. However, productivity and disturbances are intrinsically linked because 1) disturbances directly affect forest productivity (e.g. via a reduction in leaf area, growing stock or resource-use efficiency), and 2) disturbance susceptibility is often coupled to a certain development phase of the forest with productivity determining the time a forest is in this specific phase of susceptibility. The objective of this paper is to provide an overview of forest productivity changes in different forest regions in Europe under climate change, and partition these changes into effects induced by climate change alone and by climate change and disturbances. We present projections of climate change impacts on forest productivity from state-of-the-art forest models that dynamically simulate forest productivity and the effects of the main European disturbance agents (fire, storm, insects), driven by the same climate scenario in seven forest case studies along a large climatic gradient throughout Europe. Our study shows that, in most cases, including disturbances in the simulations exaggerate ongoing productivity declines or cancel out productivity gains in response to climate change. In fewer cases, disturbances also increase productivity or buffer climate-change induced productivity losses, e.g. because low severity fires can alleviate resource competition and increase fertilization. Even though our results cannot simply be extrapolated to other types of forests and disturbances, we argue that it is necessary to interpret climate change-induced productivity and disturbance changes jointly to capture the full range of climate change impacts on forests and to plan adaptation measures.

  1. Forest Products Industry of the Future

    SciTech Connect

    Los Alamos Technical Associates, Inc

    2002-05-01

    Los Alamos Technical Associates, Inc (LATA) conducted an evaluation of the potential impact and value of a portion of the current portfolio of r&d projects supported by the Office of Industrial Technology and the Forest Products Industry of the Future. The mission of the evaluation was to (a) assess the potential impact of the projects to meet the critical goals of the industry as identified in the vision and roadmapping documents. (b) Evaluate the relationship between the current portfolio of projects and the Agenda 202 Implementation Plan. In addition, evaluate the relationship between the portfolio and the newly revised draft technology strategy being created by the industry. (c) Identify areas where current efforts are making significant progress towards meeting industry goals and identify areas where additional work my be required to meet these goals. (d) Make recommendations to the DOE and the Forest Products Industry on possible improvements in the portfolio and in the current methodology that DOE uses to assess potential impacts on its R&D activities.

  2. Soil production in forested landscapes (Invited)

    NASA Astrophysics Data System (ADS)

    Roering, J. J.; Booth, A. M.

    2009-12-01

    One of the most fundamental characteristics that defines landscapes is the presence or absence of a soil mantle. In actively eroding terrain, soil (and other natural resources that depend on it) persists only when the rate of soil production is not eclipsed by denudation. Despite successful efforts to empirically estimate long-term rates of soil production, little predictive capability exists as soil formation results from a complex interplay of biological, physical, and chemical processes. Here, we synthesize a suite of observations from the steep, forested Oregon Coast Range (OCR) and anlayze the role of trees in the conversion of bedrock to soil. Pit/mound topography on forest floors attests to the persistent, wholesale overturning of soil by tree root activity. Using airborne LiDAR data for our study site in the western Oregon Coast Range, we calculated how terrain roughness varies with spatial scale. At scales greater than 10m, the well-established ridge/valley structure of the landscape defines the topography; whereas for scales less than 7m, terrain roughness increases rapidly reflecting the stochastic nature of bioturbation associated with large, coniferous trees. Empirical estimates of soil production in the OCR by Heimsath et al (2001, ESPL) reveal that production rates decrease exponentially with depth and the decay constant is 2.68 (1/m). From dozens of soil pits in the OCR, we show that the density of trees roots declines exponentially with depth at a similar rate, 2.57 (1/m). In other words, rates of soil production appear to be well-correlated with root density. Bedrock is often excavated during tree turnover events and we documented that the volume of bedrock incorporated in overturned coniferous rootwads increases rapidly for tree diameters greater than 0.5m (which correponds to a 60-80 yr old Douglas fir tree in Western Oregon). Smaller (and thus younger) trees entrain negligible bedrock when overturned, suggesting that their root systems are

  3. [Basic theory and research method of urban forest ecology].

    PubMed

    He, Xingyuan; Jin, Yingshan; Zhu, Wenquan; Xu, Wenduo; Chen, Wei

    2002-12-01

    With the development of world economy and the increment of urban population, the urban environment problem hinders the urban sustainable development. Now, more and more people realized the importance of urban forests in improving the quality of urban ecology. Therefore, a new subject, urban forest ecology, and correlative new concept frame in the field formed. The theoretic foundation of urban forest ecology derived from the mutual combination of theory relating to forest ecology, landscape ecology, landscape architecture ecology and anthrop-ecology. People survey the development of city from the view of ecosystem, and regard the environment, a colony of human, animals and plants, as main factors of the system. The paper introduces systematically the urban forest ecology as follows: 1) the basic concept of urban forest ecology; 2) the meaning of urban forest ecology; 3) the basic principle and theoretic base of urban forest ecology; 4) the research method of urban forest ecology; 5) the developmental expectation of urban forest ecology.

  4. 36 CFR 223.277 - Forest botanical products definition.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ..., pine straw, roots, sedges, seeds, shrubs, transplants, tree sap, and wildflowers. Forest botanical products are not animals, animal parts, Christmas trees, fence material, firewood, insects, mine...

  5. Alternative Bioenergy: Small Scale Pellet Production from Forest Residues

    NASA Astrophysics Data System (ADS)

    Cochran, Audra S.

    Forests can readily supply feedstock for alternative bioenergy production. Feedstock removal has the potential to benefit forest health and provide ecosystem services, while also generating profit for landowners, contractors and forest managers. However, many landowners are faced with the challenge of managing forest residuals to meet slash compliances and fire regulations. Currently, most residuals are burned or left on site to decompose. Every year, the north-central Idaho region produces over 16 million dry tons of unutilized forest residues. In a time where alternative energy sources are growing in demand, new approaches to utilize these residuals for bioenergy production are being examined. One approach is a portable, small-scale wood pellet mill that can be taken directly to the logging site. Utilizing forest residues for pellet production reduces residue burning and its potential negative impacts on air quality. This presentation focuses on the quality of wood pellets manufactured by a portable wood pellet mill utilizing various forms of forest residuals.

  6. Agenda 2020: A Technology Vision and Research Agenda for America's Forest, Wood and Paper Industry

    SciTech Connect

    none,

    1994-11-01

    In November 1994, the forest products industry published Agenda 2020: A Technology Vision and Research Agenda for America's Forest, Wood and Paper Industry, which articulated the industry's vision. This document set the foundation for collaborative efforts between the industry and the federal government.

  7. 77 FR 65095 - National Forest Products Week, 2012

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-24

    ... Documents#0;#0; ] Proclamation 8892 of October 19, 2012 National Forest Products Week, 2012 By the President... environments for us to explore. During National Forest Products Week, we celebrate sustainable uses of the... to our progress in the years ahead. This week, let us rededicate ourselves to managing our...

  8. 78 FR 62957 - National Forest Products Week, 2013

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-10-23

    ... Documents#0;#0; ] Proclamation 9044 of October 18, 2013 National Forest Products Week, 2013 By the President... recreation for workers and families across our country. During National Forest Products Week, we celebrate... week, we recommit to collaborating across land ownership and landscapes, and we look to a future...

  9. 43 CFR 9265.4 - Sales of forest products, general.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 43 Public Lands: Interior 2 2011-10-01 2011-10-01 false Sales of forest products, general. 9265.4 Section 9265.4 Public Lands: Interior Regulations Relating to Public Lands (Continued) BUREAU OF LAND... Vegetative Resources Management § 9265.4 Sales of forest products, general. Commission of any of the...

  10. 43 CFR 9265.4 - Sales of forest products, general.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 43 Public Lands: Interior 2 2014-10-01 2014-10-01 false Sales of forest products, general. 9265.4 Section 9265.4 Public Lands: Interior Regulations Relating to Public Lands (Continued) BUREAU OF LAND... Vegetative Resources Management § 9265.4 Sales of forest products, general. Commission of any of the...

  11. 43 CFR 9265.4 - Sales of forest products, general.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 43 Public Lands: Interior 2 2013-10-01 2013-10-01 false Sales of forest products, general. 9265.4 Section 9265.4 Public Lands: Interior Regulations Relating to Public Lands (Continued) BUREAU OF LAND... Vegetative Resources Management § 9265.4 Sales of forest products, general. Commission of any of the...

  12. 43 CFR 9265.4 - Sales of forest products, general.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 43 Public Lands: Interior 2 2012-10-01 2012-10-01 false Sales of forest products, general. 9265.4 Section 9265.4 Public Lands: Interior Regulations Relating to Public Lands (Continued) BUREAU OF LAND... Vegetative Resources Management § 9265.4 Sales of forest products, general. Commission of any of the...

  13. 36 CFR 261.6 - Timber and other forest products.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... or otherwise damaging any timber, tree, or other forest product, except as authorized by a special-use authorization, timber sale contract, or Federal law or regulation. (b) Cutting any standing tree... otherwise identifying any tree or other forest product in a manner similar to that employed by...

  14. New perspectives in forest management: Background, science issues, and research agenda. Forest Service research paper

    SciTech Connect

    Brooks, D.J.; Grant, G.E.

    1992-09-01

    Scientific, management, and social factors that have contributed to the changes in United States forest management are examined in the report. Principles underlying new approaches are developed and implications are considered at various spatial and temporal scales. A general framework for a research program is outlined.

  15. Final Progress Report on Model-Based Diagnosis of Soil Limitations to Forest Productivity

    SciTech Connect

    Luxmoore, R.J.

    2004-08-30

    This project was undertaken in support of the forest industry to link modeling of nutrients and productivity with field research to identify methods for enhancing soil quality and forest productivity and for alleviating soil limitations to sustainable forest productivity. The project consisted of a series of related tasks, including (1) simulation of changes in biomass and soil carbon with nitrogen fertilization, (2) development of spreadsheet modeling tools for soil nutrient availability and tree nutrient requirements, (3) additional modeling studies, and (4) evaluation of factors involved in the establishment and productivity of southern pine plantations in seasonally wet soils. This report also describes the two Web sites that were developed from the research to assist forest managers with nutrient management of Douglas-fir and loblolly pine plantations.

  16. Modeling Forest Productivity Using Envisat MERIS Data

    PubMed Central

    Berberoglu, Suha; Evrendilek, Fatih; Ozkan, Coskun; Donmez, Cenk

    2007-01-01

    The aim of this study was to derive land cover products with a 300-m pixel resolution of Envisat MERIS (Medium Resolution Imaging Spectrometer) to quantify net primary productivity (NPP) of conifer forests of Taurus Mountain range along the Eastern Mediterranean coast of Turkey. The Carnegie-Ames-Stanford approach (CASA) was used to predict annual and monthly regional NPP as modified by temperature, precipitation, solar radiation, soil texture, fractional tree cover, land cover type, and normalized difference vegetation index (NDVI). Fractional tree cover was estimated using continuous training data and multi-temporal metrics of 47 Envisat MERIS images of March 2003 to September 2005 and was derived by aggregating tree cover estimates made from high-resolution IKONOS imagery to coarser Landsat ETM imagery. A regression tree algorithm was used to estimate response variables of fractional tree cover based on the multi-temporal metrics. This study showed that Envisat MERIS data yield a greater spatial detail in the quantification of NPP over a topographically complex terrain at the regional scale than those used at the global scale such as AVHRR.

  17. Upland forests of the American/Pacific islands: Research opportunities in Micronesia and American Samoa. Forest Service general technical report (Final)

    SciTech Connect

    DeBell, D.S.; Whitesell, C.D.

    1993-07-01

    The Upland forests of Micronesia and American Samoa can provide many social, ecological, and esthetic benefits for island inhabitants. Substantial upland areas (the majority of acreage on some islands) are now occupied by secondary and grassland/savanna vegetation: such areas represent opportunities for restoration, with both native forest cover and plantations of introduced species. The review briefly describes characteristics of the islands and the nature of existing and potential upland forests, including the most common upland tree species. Principal information needs and research opportunities are discussed for 10 subjects: watershed rehabilitation, forest restoration in secondary vegetation areas, basic ecology, soils and nutrient relationships, damaging agents, forest inventory and productivity assessment, silvicultural systems, valuation of forest products and services, threatened and endangered species, and description and protection of native forest habitats.

  18. 36 CFR 223.278 - Sale of forest botanical products and collection of fees.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 36 Parks, Forests, and Public Property 2 2013-07-01 2013-07-01 false Sale of forest botanical products and collection of fees. 223.278 Section 223.278 Parks, Forests, and Public Property FOREST SERVICE, DEPARTMENT OF AGRICULTURE SALE AND DISPOSAL OF NATIONAL FOREST SYSTEM TIMBER, SPECIAL FOREST PRODUCTS,...

  19. 36 CFR 223.217 - Authority to dispose of special forest products.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 36 Parks, Forests, and Public Property 2 2014-07-01 2014-07-01 false Authority to dispose of special forest products. 223.217 Section 223.217 Parks, Forests, and Public Property FOREST SERVICE, DEPARTMENT OF AGRICULTURE SALE AND DISPOSAL OF NATIONAL FOREST SYSTEM TIMBER, SPECIAL FOREST PRODUCTS,...

  20. 36 CFR 223.217 - Authority to dispose of special forest products.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 36 Parks, Forests, and Public Property 2 2013-07-01 2013-07-01 false Authority to dispose of special forest products. 223.217 Section 223.217 Parks, Forests, and Public Property FOREST SERVICE, DEPARTMENT OF AGRICULTURE SALE AND DISPOSAL OF NATIONAL FOREST SYSTEM TIMBER, SPECIAL FOREST PRODUCTS,...

  1. 36 CFR 223.241 - Disposal of seized special forest products.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 36 Parks, Forests, and Public Property 2 2011-07-01 2011-07-01 false Disposal of seized special forest products. 223.241 Section 223.241 Parks, Forests, and Public Property FOREST SERVICE, DEPARTMENT OF AGRICULTURE SALE AND DISPOSAL OF NATIONAL FOREST SYSTEM TIMBER, SPECIAL FOREST PRODUCTS,...

  2. 36 CFR 223.278 - Sale of forest botanical products and collection of fees.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 36 Parks, Forests, and Public Property 2 2014-07-01 2014-07-01 false Sale of forest botanical products and collection of fees. 223.278 Section 223.278 Parks, Forests, and Public Property FOREST SERVICE, DEPARTMENT OF AGRICULTURE SALE AND DISPOSAL OF NATIONAL FOREST SYSTEM TIMBER, SPECIAL FOREST PRODUCTS,...

  3. 36 CFR 223.278 - Sale of forest botanical products and collection of fees.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 36 Parks, Forests, and Public Property 2 2010-07-01 2010-07-01 false Sale of forest botanical products and collection of fees. 223.278 Section 223.278 Parks, Forests, and Public Property FOREST SERVICE, DEPARTMENT OF AGRICULTURE SALE AND DISPOSAL OF NATIONAL FOREST SYSTEM TIMBER Forest Botanical Products §...

  4. 36 CFR 223.217 - Authority to dispose of special forest products.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 36 Parks, Forests, and Public Property 2 2012-07-01 2012-07-01 false Authority to dispose of special forest products. 223.217 Section 223.217 Parks, Forests, and Public Property FOREST SERVICE, DEPARTMENT OF AGRICULTURE SALE AND DISPOSAL OF NATIONAL FOREST SYSTEM TIMBER, SPECIAL FOREST PRODUCTS,...

  5. 36 CFR 223.278 - Sale of forest botanical products and collection of fees.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 36 Parks, Forests, and Public Property 2 2011-07-01 2011-07-01 false Sale of forest botanical products and collection of fees. 223.278 Section 223.278 Parks, Forests, and Public Property FOREST SERVICE, DEPARTMENT OF AGRICULTURE SALE AND DISPOSAL OF NATIONAL FOREST SYSTEM TIMBER, SPECIAL FOREST PRODUCTS,...

  6. 36 CFR 223.217 - Authority to dispose of special forest products.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 36 Parks, Forests, and Public Property 2 2010-07-01 2010-07-01 false Authority to dispose of special forest products. 223.217 Section 223.217 Parks, Forests, and Public Property FOREST SERVICE, DEPARTMENT OF AGRICULTURE SALE AND DISPOSAL OF NATIONAL FOREST SYSTEM TIMBER Special Forest Products §...

  7. 36 CFR 223.217 - Authority to dispose of special forest products.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 36 Parks, Forests, and Public Property 2 2011-07-01 2011-07-01 false Authority to dispose of special forest products. 223.217 Section 223.217 Parks, Forests, and Public Property FOREST SERVICE, DEPARTMENT OF AGRICULTURE SALE AND DISPOSAL OF NATIONAL FOREST SYSTEM TIMBER, SPECIAL FOREST PRODUCTS,...

  8. 36 CFR 223.278 - Sale of forest botanical products and collection of fees.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 36 Parks, Forests, and Public Property 2 2012-07-01 2012-07-01 false Sale of forest botanical products and collection of fees. 223.278 Section 223.278 Parks, Forests, and Public Property FOREST SERVICE, DEPARTMENT OF AGRICULTURE SALE AND DISPOSAL OF NATIONAL FOREST SYSTEM TIMBER, SPECIAL FOREST PRODUCTS,...

  9. Positive biodiversity-productivity relationship predominant in global forests

    USGS Publications Warehouse

    Liang, Jingjing; Crowther, Thomas W.; Picard, Nicolas; Wiser, Susan; Zhou, Mo; Alberti, Giorgio; Schulze, Ernst-Detlef; McGuire, Anthony David; ,

    2016-01-01

    The relationship between biodiversity and ecosystem productivity has been explored in detail in herbaceous vegetation, but patterns in forests are far less well understood. Liang et al. have amassed a global forest data set from >770,000 sample plots in 44 countries. A positive and consistent relationship can be discerned between tree diversity and ecosystem productivity at landscape, country, and ecoregion scales. On average, a 10% loss in biodiversity leads to a 3% loss in productivity. This means that the economic value of maintaining biodiversity for the sake of global forest productivity is more than fivefold greater than global conservation costs.

  10. Usage of non-timber forest products by women in forest villages of Trabzon, Turkey.

    PubMed

    Toksoy, Devlet; Alkan, Suleyman; Hacisalihoglu, Sezgin

    2010-11-01

    Women are responsible for procuring the food for their family in many places in the world. The usage of the non-timber forest products (NTFPs) reaches to the beginning of the humanity NTFPs are used for food and medicine especially in the developing countries as a whole. In this research, totally 611 questionnaires were conducted with women participants by polling face to face in 68 forest villages in the research area. The main reason for studying with women is that; the gathering activities are usually done by women in that area and they also knew the used parts and how to use the NTFPs. Results showed that about 14.4% of the women in the research area are gathering the plants for food (17 species and 2-8 kg annually) and 9.2% of the women are gathering the plants for medicinal purposes (16 species and 1-4 kg annually). These plants are usually used for additional medicinal treatments. 4 species are used for livestock treatment and 2 species in the hand weaving.

  11. Production, prices, employment, and trade in northwest forest industries, first quarter 1993. Forest Service resource bulletin

    SciTech Connect

    Warren, D.D.

    1993-11-01

    The report includes current information on lumber and plywood production and prices; employment in the forest industries; international trade in logs, lumber, and plywood; volume and average prices of stumpage sold by public agencies; and other related items.

  12. Production, prices, employment, and trade in northwest forest industries, second quarter 1997. Forest Service resource bulletin

    SciTech Connect

    Warren, D.D.

    1998-03-01

    Provides current information on lumber and plywood production and prices; employment in the forest industries; international trade in logs, lumber, and plywood; volume and average prices of stumpage sold by public agencies; and other related items.

  13. Production, prices, employment, and trade in northwest forest industries, fourth quarter 1993. Forest Service resource bulletin

    SciTech Connect

    Warren, D.D.

    1994-05-01

    The report includes current information on lumber and plywood production and prices; employment in the forest industries; international trade in logs, lumber, and plywood, volume and average prices in stumpage sold by public agencies; and other related items.

  14. Production, prices, employment, and trade in northwest forest industries, third quarter 1992. Forest Service resource bulletin

    SciTech Connect

    Warren, D.D.

    1993-03-01

    The report includes current information on lumber and plywood production and prices; employment in the forest industries; international trade in logs, lumber, and plywood; volume and average prices of stumpage sold by public agencies; and other related items.

  15. Production, prices, employment, and trade in northwest forest industries, first quarter 1995. Forest Service resource bulletin

    SciTech Connect

    Warren, D.D.

    1995-09-01

    Provides current information on lumber and plywood production and prices; employment in the forest industries; international trade in logs, lumber, and plywood, volume and average prices of stumpage sold by public agencies; and other related items.

  16. Production, prices, employment, and trade in northwest forest industries, second quarter 1994. Forest Service resource bulletin

    SciTech Connect

    Warren, D.D.

    1995-01-01

    The report provides current information on lumber and plywood production and prices; employment in the forest industries; international trade in logs, lumber, and plywood, volume and average prices of stumpage sold by public agencies; and other related items.

  17. Production, prices, employment, and trade in northwest forest industries, third quarter 1996. Forest Service resource bulletin

    SciTech Connect

    Warren, D.D.

    1997-02-01

    Provides current information on lumber and plywood production and prices; employment in the forest industries; international trade in logs, lumber, and plywood; volume and average prices of stumpage sold by public agencies; and other related items.

  18. Production, prices, employment, and trade in northwest forest industries, second quarter 1992. Forest Service resource bulletin

    SciTech Connect

    Warren, D.D.

    1992-01-01

    The report provides current information on lumber and plywood production and prices; employment in the forest industries; international trade in logs, lumber, and plywood; volume and average prices of stumpage sold by public agencies; and other related items.

  19. Production, prices, employment, and trade in northwest forest industries, fourth quarter 1992. Forest Service resource bulletin

    SciTech Connect

    Warren, D.D.

    1993-07-01

    The report provides current information on lumber and plywood production and prices; employment in the forest industries; international trade in logs, lumber, and plywood; volume and average prices of stumpage sold by public agencies; and other related items.

  20. Production, prices, employment and trade in northwest forest industries, second quarter 1996. Forest Service resource bulletin

    SciTech Connect

    Warren, D.D.

    1996-11-01

    The report provides current information on lumber and plywood production and prices; employment in the forest industries; international trade in logs, lumber, and plywood; volume and average prices of stumpage sold by public agencies; and other related items.

  1. Production, prices, employment, and trade in northwest forest industries, second quarter 1993. Forest Service resource bulletin

    SciTech Connect

    Warren, D.D.

    1994-01-01

    The report includes current information on lumber and plywood production and prices, employment in the forest industries; international trade in logs, lumber and plywood; volume and average prices of stumpage sold by public agencies; and other related items.

  2. Production, prices, employment, and trade in northwest forest industries, first quarter 1994. Forest Service resource bulletin

    SciTech Connect

    Warren, D.D.

    1994-11-01

    The report provides current information on lumber and plywood production and prices; employment in the forest industries; international trade in logs, lumber, and plywood, volume and average prices of stumpage sold by public agencies; and other related items.

  3. Production, prices, employment, and trade in northwest forest industries, second quarter 1995. Forest Service resource bulletin

    SciTech Connect

    Warren, D.D.

    1996-01-01

    Provides current information on lumber and plywood production and prices; employment in the forest industries; international trade in logs, lumber, and plywood; volume and average prices of stumpage sold by public agencies; and other related items.

  4. Production, prices, employment, and trade in northwest forest industries, fourth quarter 1996. Forest Service resource bulletin

    SciTech Connect

    Warren, D.D.

    1997-07-01

    Provides current information on lumber and plywood production and prices; employment in the forest industries; international trade in logs, lumber, and plywood; volume and average prices of stumpage sold by public agencies; and other related items.

  5. Production, prices, employment, and trade in northwest forest industries, first quarter 1996. Forest Service resource bulletin

    SciTech Connect

    Warren, D.D.

    1996-07-01

    Provides current information on lumber and plywood production and prices; employment in the forest industries; international trade in logs, lumber, and plywood, volume and average prices of stumpage sold by public agencies; and other related items.

  6. 25 CFR 163.37 - Forest management research.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 25 Indians 1 2014-04-01 2014-04-01 false Forest management research. 163.37 Section 163.37 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER GENERAL FORESTRY REGULATIONS Forest... authorized Indian representatives' is authorized to perform forestry research activities to improve the...

  7. 25 CFR 163.37 - Forest management research.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 25 Indians 1 2013-04-01 2013-04-01 false Forest management research. 163.37 Section 163.37 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER GENERAL FORESTRY REGULATIONS Forest... authorized Indian representatives' is authorized to perform forestry research activities to improve the...

  8. 25 CFR 163.37 - Forest management research.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 25 Indians 1 2011-04-01 2011-04-01 false Forest management research. 163.37 Section 163.37 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER GENERAL FORESTRY REGULATIONS Forest... authorized Indian representatives' is authorized to perform forestry research activities to improve the...

  9. 25 CFR 163.37 - Forest management research.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false Forest management research. 163.37 Section 163.37 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER GENERAL FORESTRY REGULATIONS Forest... authorized Indian representatives' is authorized to perform forestry research activities to improve the...

  10. 25 CFR 163.37 - Forest management research.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 25 Indians 1 2012-04-01 2011-04-01 true Forest management research. 163.37 Section 163.37 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER GENERAL FORESTRY REGULATIONS Forest... authorized Indian representatives' is authorized to perform forestry research activities to improve the...

  11. Interpreting forest and grassland biome productivity utilizing nested scales of image resolution and biogeographical analysis

    NASA Technical Reports Server (NTRS)

    Iverson, Louis R.; Cook, Elizabeth A.; Graham, Robin L.; Olson, Jerry S.; Frank, Thomas; Ke, Ying; Treworgy, Colin; Risser, Paul G.

    1987-01-01

    This report summarizes progress made in our investigation of forest productivity assessment using TM and other biogeographical data during the third six-month period of the grant. Data acquisition and methodology hurdles are largely complete. Four study areas for which the appropriate TM and ancillary data were available are currently being intensively analyzed. Significant relationships have been found on a site by site basis to suggest that forest productivity can be qualitatively assessed using TM band values and site characteristics. Perhaps the most promising results relate TM unsupervised classes to forest productivity, with enhancement from elevation data. During the final phases of the research, multi-temporal and regional comparisons of results will be addressed, as well as the predictability of forest productivity patterns over a large region using TM data and/or TM nested within AVHRR data.

  12. Information system of forest growth and productivity by site quality type and elements of forest

    NASA Astrophysics Data System (ADS)

    Khlyustov, V.

    2012-04-01

    Information system of forest growth and productivity by site quality type and elements of forest V.K. Khlustov Head of the Forestry Department of Russian State Agrarian University named after K.A.Timiryazev doctor of agricultural sciences, professor The efficiency of forest management can be improved substantially by development and introduction of principally new models of forest growth and productivity dynamics based on regionalized site specific parameters. Therefore an innovative information system was developed. It describes the current state and gives a forecast for forest stand parameters: growth, structure, commercial and biological productivity depend on type of site quality. In contrast to existing yield tables, the new system has environmental basis: site quality type. The information system contains set of multivariate statistical models and can work at the level of individual trees or at the stand level. The system provides a graphical visualization, as well as export of the emulation results. The System is able to calculate detailed description of any forest stand based on five initial indicators: site quality type, site index, stocking, composition, and tree age by elements of the forest. The results of the model run are following parameters: average diameter and height, top height, number of trees, basal area, growing stock (total, commercial with distribution by size, firewood and residuals), live biomass (stem, bark, branches, foliage). The system also provides the distribution of mentioned above forest stand parameters by tree diameter classes. To predict the future forest stand dynamics the system require in addition the time slot only. Full set of forest parameters mention above will be provided by the System. The most conservative initial parameters (site quality type and site index) can be kept in the form of geo referenced polygons. In this case the system would need only 3 dynamic initial parameters (stocking, composition and age) to

  13. 36 CFR 223.216 - Special Forest Products definitions.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    .... Special forest products do not include sawtimber, pulpwood, non-sawlog material removed in log form, cull logs, small roundwood, house logs, telephone poles, derrick poles, minerals, animals, animal...

  14. Structure and Evolution of Mediterranean Forest Research: A Science Mapping Approach.

    PubMed

    Nardi, Pierfrancesco; Di Matteo, Giovanni; Palahi, Marc; Scarascia Mugnozza, Giuseppe

    2016-01-01

    This study aims at conducting the first science mapping analysis of the Mediterranean forest research in order to elucidate its research structure and evolution. We applied a science mapping approach based on co-term and citation analyses to a set of scientific publications retrieved from the Elsevier's Scopus database over the period 1980-2014. The Scopus search retrieved 2,698 research papers and reviews published by 159 peer-reviewed journals. The total number of publications was around 1% (N = 17) during the period 1980-1989 and they reached 3% (N = 69) in the time slice 1990-1994. Since 1995, the number of publications increased exponentially, thus reaching 55% (N = 1,476) during the period 2010-2014. Within the thirty-four years considered, the retrieved publications were published by 88 countries. Among them, Spain was the most productive country, publishing 44% (N = 1,178) of total publications followed by Italy (18%, N = 482) and France (12%, N = 336). These countries also host the ten most productive scientific institutions in terms of number of publications in Mediterranean forest subjects. Forest Ecology and Management and Annals of Forest Science were the most active journals in publishing research in Mediterranean forest. During the period 1980-1994, the research topics were poorly characterized, but they become better defined during the time slice 1995-1999. Since 2000s, the clusters become well defined by research topics. Current status of Mediterranean forest research (20092014) was represented by four clusters, in which different research topics such as biodiversity and conservation, land-use and degradation, climate change effects on ecophysiological responses and soil were identified. Basic research in Mediterranean forest ecosystems is mainly conducted by ecophysiological research. Applied research was mainly represented by land-use and degradation, biodiversity and conservation and fire research topics. The citation analyses revealed highly

  15. Structure and Evolution of Mediterranean Forest Research: A Science Mapping Approach

    PubMed Central

    Nardi, Pierfrancesco; Di Matteo, Giovanni; Palahi, Marc; Scarascia Mugnozza, Giuseppe

    2016-01-01

    This study aims at conducting the first science mapping analysis of the Mediterranean forest research in order to elucidate its research structure and evolution. We applied a science mapping approach based on co-term and citation analyses to a set of scientific publications retrieved from the Elsevier’s Scopus database over the period 1980–2014. The Scopus search retrieved 2,698 research papers and reviews published by 159 peer-reviewed journals. The total number of publications was around 1% (N = 17) during the period 1980–1989 and they reached 3% (N = 69) in the time slice 1990–1994. Since 1995, the number of publications increased exponentially, thus reaching 55% (N = 1,476) during the period 2010–2014. Within the thirty-four years considered, the retrieved publications were published by 88 countries. Among them, Spain was the most productive country, publishing 44% (N = 1,178) of total publications followed by Italy (18%, N = 482) and France (12%, N = 336). These countries also host the ten most productive scientific institutions in terms of number of publications in Mediterranean forest subjects. Forest Ecology and Management and Annals of Forest Science were the most active journals in publishing research in Mediterranean forest. During the period 1980–1994, the research topics were poorly characterized, but they become better defined during the time slice 1995–1999. Since 2000s, the clusters become well defined by research topics. Current status of Mediterranean forest research (20092014) was represented by four clusters, in which different research topics such as biodiversity and conservation, land-use and degradation, climate change effects on ecophysiological responses and soil were identified. Basic research in Mediterranean forest ecosystems is mainly conducted by ecophysiological research. Applied research was mainly represented by land-use and degradation, biodiversity and conservation and fire research topics. The citation analyses

  16. Responses of temperate forest productivity to insect and pathogen disturbances

    NASA Astrophysics Data System (ADS)

    Flower, C. E.; Gonzalez-Meler, M. A.

    2014-12-01

    Climate forcing factors have been documented to directly (e.g. CO2 fertilization) or indirectly (e.g. temperature and vapor pressure deficit) affect net primary productivity (NPP) of forests. Climate variations can also affect the vulnerability of forests to pests and pathogens, causing diffuse or widespread mortality. The introduction of novel pests is causing rapid mortality of targeted species with undetermined effects on forest productivity: NPP could decrease or increase depending on the severity (proportion of basal area impacted) and species diversity. We attempted to document the impact of diffuse mortality caused by insect outbreaks on North American temperate forests through synthesis of literature. Despite the large number of studies (>500) only a few (12) documented NPP in a systematic manner. The magnitude of insect and pathogen disturbance was larger in western than eastern forests due to the redundancy and functional diversity of temperate deciduous and mixed deciduous forests. Recovery from disturbance was more rapid from diffuse short duration defoliation events relative to the long lasting impacts of wood boring insects. Forest resilience may decrease as insect disturbance increases, particularly with generalist invasive pests that target a variety of species. We conclude that these biotic interactions, particularly when caused by invasive pests, impose biological forcing to forest NPP at similar magnitude and time scales than climate forcing.

  17. Changes in forest productivity across Alaska consistent with biome shift.

    PubMed

    Beck, Pieter S A; Juday, Glenn P; Alix, Claire; Barber, Valerie A; Winslow, Stephen E; Sousa, Emily E; Heiser, Patricia; Herriges, James D; Goetz, Scott J

    2011-04-01

    Global vegetation models predict that boreal forests are particularly sensitive to a biome shift during the 21st century. This shift would manifest itself first at the biome's margins, with evergreen forest expanding into current tundra while being replaced by grasslands or temperate forest at the biome's southern edge. We evaluated changes in forest productivity since 1982 across boreal Alaska by linking satellite estimates of primary productivity and a large tree-ring data set. Trends in both records show consistent growth increases at the boreal-tundra ecotones that contrast with drought-induced productivity declines throughout interior Alaska. These patterns support the hypothesized effects of an initiating biome shift. Ultimately, tree dispersal rates, habitat availability and the rate of future climate change, and how it changes disturbance regimes, are expected to determine where the boreal biome will undergo a gradual geographic range shift, and where a more rapid decline.

  18. Research Productivity and Tenure.

    ERIC Educational Resources Information Center

    McNurlen, Brian; West, Charles K.

    This study examined research productivity over the course of the professional career and its relationship with tenure. It hypothesized that the rate of scholarly productivity does not decrease after tenure, and further, that the amount of activity of older faculty is comparable to new faculty. Data were collected from the curriculum vitae of…

  19. Research Productivity: A Definition.

    ERIC Educational Resources Information Center

    Zamarripa, Edward J.

    1993-01-01

    This study compared attitudes of scientists associated with (n=79) or not associated with (n=70) a mental retardation research center, concerning preferred measures of research productivity at such centers. Data showed consistency in responses of groups. A ranking of 25 measures was developed, with publication in refereed journals ranked highest.…

  20. Forest product use at an upper elevation village in Nepal

    NASA Astrophysics Data System (ADS)

    Metz, John J.

    1994-05-01

    This paper describes forest product use at Chimkhola, an upper elevation village of west central Nepal. Villagers have large herds of livestock that they use to fertilize agricultural fields by holding the animals on cropland for one to several weeks prior to planting. Herds are moved sequentially from one group of fields to another until all are planted, and then families take animals into the forests. Herders, therefore, live in temporary shelters away from the homestead throughout the year, and for much of the year feed their livestock fodder cut from forest trees. By combining repeated interviews of sample households, one-time interviews with a large sample of village families, and direct measurements of forest products being used, I found that livestock maintenance consumes 74% of the hand-harvested wild biomass: 26.4% for green fodder, 32.3% for fuelwood at the herder's hut, and 13.8% for construction of the herder's hut. Fuelwood burned at the homestead is the next largest consumer, 17.6%. Villagers also use small amounts of forest materials for house construction, charcoal, agricultural implements, and bamboo for baskets and mats. The large amounts used by herders and livestock at Chimkhola mean that wild vegetation use there far exceeds the measurements made by previous reliable studies at other communities. This system of forest use is, however, degrading Chimkhola's forests and gradually converting them to shrublands.

  1. Responses of temperate forest productivity to insect and pathogen disturbances.

    PubMed

    Flower, Charles E; Gonzalez-Meler, Miquel A

    2015-01-01

    Pest and pathogen disturbances are ubiquitous across forest ecosystems, impacting their species composition, structure, and function. Whereas severe abiotic disturbances (e.g., clear-cutting and fire) largely reset successional trajectories, pest and pathogen disturbances cause diffuse mortality, driving forests into nonanalogous system states. Biotic perturbations that disrupt forest carbon dynamics either reduce or enhance net primary production (NPP) and carbon storage, depending on pathogen type. Relative to defoliators, wood borers and invasive pests have the largest negative impact on NPP and the longest recovery time. Forest diversity is an important contributing factor to productivity: NPP is neutral, marginally enhanced, or reduced in high-diversity stands in which a small portion of the canopy is affected (temperate deciduous or mixed forests) but very negative in low-diversity stands in which a large portion of the canopy is affected (western US forests). Pests and pathogens reduce forest structural and functional redundancy, affecting their resilience to future climate change or new outbreaks. Therefore, pests and pathogens can be considered biotic forcing agents capable of causing consequences of similar magnitude to climate forcing factors.

  2. Regulatory and information support for evaluation of biological productivity of Ukrainian forests and climate change

    NASA Astrophysics Data System (ADS)

    Lakyda, Petro; Vasylyshyn, Roman; Lakyda, Ivan

    2013-04-01

    Stabilization and preservation of the planet's climate system today is regarded as one of the most important global political-economic, environmental and social problems of mankind. Rising concentration of carbon dioxide in the planet's atmosphere due to anthropogenic impact is the main reason leading to global climate change. Due to the above mentioned, social demands on forests are changing their biosphere role and function of natural sink of greenhouse gases becomes top priority. It is known that one of the most essential components of biological productivity of forests is their live biomass. Absorption, long-term sequestration of carbon and generation of oxygen are secured by its components. System research of its parametric structure and development of regulatory and reference information for assessment of aboveground live biomass components of trees and stands of the main forest-forming tree species in Ukraine began over twenty-five years ago at the department of forest mensuration and forest inventory of National University of Life and Environmental Sciences of Ukraine, involving staff from other research institutions. Today, regulatory and reference materials for evaluation of parametric structure of live biomass are developed for trees of the following major forest-forming tree species of Ukraine: Scots pine of natural and artificial origin, Crimean pine, Norway spruce, silver fir, pedunculate oak, European beech, hornbeam, ash, common birch, aspen and black alder (P.I. Lakyda et al., 2011). An ongoing process on development of similar regulatory and reference materials for forest stands of the abovementioned forest-forming tree species of Ukraine is secured by scientists of departments of forest management, and forest mensuration and forest inventory. The total experimental research base is 609 temporary sample plots, where 4880 model trees were processed, including 3195 model trees with estimates of live biomass components. Laboratory studies conducted

  3. Production, prices, employment, and trade in northwest forest industries, third quarter 1994. Forest Service resource bulletin

    SciTech Connect

    Warren, D.D.

    1995-03-01

    The report presents current information on the timber situation in Alaska, Washington, Oregon, California, Montana, Idaho, and British Columbia, including data on lumber and plywood production and prices; timber harvest; employment in forest products industries; international trade in logs, pulpwood, chips, lumber, and plywood; log prices in the Pacific Northwest; volume and average prices of stumpage sold by public agencies; and other related items.

  4. Production, prices, employment, and trade in northwest forest industries, fourth quarter 1995. Forest Service resource bulletin

    SciTech Connect

    Warren, D.D.

    1996-06-01

    This report presents current information on the timber situation in Alaska, Washington, Oregon, California, Montana, Idaho, and British Columbia, including data on lumber and plywood production and prices; timber harvest; employment in forest products industries; international trade in logs, pulpwood, chips, lumber, and plywood; log prices in the Pacific Northwest; volume and average prices of stumpage sold by public agencies; and other related items.

  5. Production, prices, employment, and trade in northwest forest industries, third quarter 1995. Forest Service resource bulletin

    SciTech Connect

    Warren, D.D.

    1996-03-01

    The report presents current information on the timber situation in Alaska, Washington, Oregon, California, Montana, Idaho, and British Columbia, including data on lumber and plywood production and prices; timber harvest; employment in forest products industries; international trade in logs, pulpwood, chips, lumber, and plywood; log prices in the Pacific Northwest; volume and average prices of stumpage sold by public agencies; and other related items.

  6. Production, prices, employment, and trade in northwest forest industries, fourth quarter 1994. Forest Service resource bulletin

    SciTech Connect

    Warren, D.D.

    1995-06-01

    The report presents current information on the timber situation in Alaska, Washington, Oregon, California, Montana, Idaho, and British Columbia, including data on lumber and plywood production and prices; timber harvest; employment in forest products industries; international trade in logs, pulpwood, chips, lumber, and plywood; log prices in the Pacific Northwest; volume and average prices of stumpage sold by public agencies; and other related items.

  7. Forest and wood products role in carbon sequestration

    SciTech Connect

    Sampson, R.N.

    1997-12-31

    An evaluation of the use of U.S. forests and forest products for carbon emission mitigation is presented. The current role of forests in carbon sequestration is described in terms of regional differences and forest management techniques. The potential for increasing carbon storage by converting marginal crop and pasture land, increasing timberland growth, reducing wildfire losses, and changing timber harvest methods is examined. Post-harvest carbon flows, environmental impacts of wood products, biomass energy crops, and increased use of energy-conserving trees are reviewed for their potential in reducing or offsetting carbon emissions. It is estimated that these techniques could offset 20 to 40 percent of the carbon emitted annually in the U.S. 39 refs., 5 tabs.

  8. Nanotechnology for the Forest Products Industry Vision and Technology Roadmap

    SciTech Connect

    Atalla, Rajai; Beecher, James; Caron, Robert; Catchmark, Jeffrey; Deng, Yulin; Glasser, Wolfgang; Gray, Derek; Haigler, Candace; Jones, Philip; Joyce, Margaret; Kohlman, Jane; Koukoulas, Alexander; Lancaster, Peter; Perine, Lori; Rodriguez, Augusto; Ragauskas, Arthur; Wegner, Theodore; Zhu, Junyong

    2005-03-01

    A roadmap for Nanotechnology in the Forest Products Industries has been developed under the umbrella of the Agenda 2020 program overseen by the CTO committee. It is expected that the use of new analytical techniques and methodologies will allow us to understand the complex nature of wood based materials and allow the dramatically enhanced use of the major strategic asset the US has in renewable, recyclable resources based on its well managed Forests.

  9. Contribution of Near Real Time MODIS-Based Forest Disturbance Detection Products to a National Forest Threat Early Warning System

    NASA Technical Reports Server (NTRS)

    Spruce, Joseph; Hargrove, William; Gasser, Gerald; Smoot, James; Kuper, Philip

    2011-01-01

    U.S. forests occupy approx. 751 million acres (approx. 1/3 of total land). These forests are exposed to multiple biotic and abiotic threats that collectively damage extensive acreages each year. Hazardous forest disturbances can threaten human life and property, bio-diversity and water supplies. Timely regional forest monitoring products are needed to aid forest management and decision making by the US Forest Service and its state and private partners. Daily MODIS data products provide a means to monitor regional forest disturbances on a weekly basis. In response, we began work in 2006 to develop a Near Real Time (NRT) forest monitoring capability, based on MODIS NDVI data, as part of a national forest threat early warning system (EWS)

  10. Gross primary production of global forest ecosystems has been overestimated

    PubMed Central

    Ma, Jianyong; Yan, Xiaodong; Dong, Wenjie; Chou, Jieming

    2015-01-01

    Coverage rate, a critical variable for gridded forest area, has been neglected by previous studies in estimating the annual gross primary production (GPP) of global forest ecosystems. In this study, we investigated to what extent the coverage rate could impact forest GPP estimates from 1982 to 2011. Here we show that the traditional calculation without considering the coverage rate globally overestimated the forest gross carbon dioxide uptake by approximately 8.7%, with a value of 5.12 ± 0.23 Pg C yr−1, which is equivalent to 48% of the annual emissions from anthropogenic activities in 2012. Actually, the global annual GPP of forest ecosystems is approximately 53.71 ± 4.83 Pg C yr−1 for the past 30 years by taking the coverage rate into account. Accordingly, we argue that forest annual GPP calculated by previous studies has been overestimated due to the exaggerated forest area, and therefore, coverage rate may be a required factor to further quantify the global carbon cycle. PMID:26027557

  11. Carabid (Coleoptera) type collection at National Forest Insect Collection (NFIC), Forest Research Institute, Dehradun (India).

    PubMed

    Faisal, Mohammad; Singh, Sudhir

    2014-04-10

    Members of family Carabidae (Insecta: Coleoptera) are a dominant group of terrestrial predators. National Forest Insect Collection (NFIC) of Forest Research Institute, Dehradun (India) has a good collection of carabids rich in type material. Here we report the details of the type specimens of 139 species included in 49 genera, 24 tribes and 14 subfamilies. Colour automontaged photographs of each type along with its original labels are also included.

  12. Positive biodiversity-productivity relationship predominant in global forests.

    PubMed

    Liang, Jingjing; Crowther, Thomas W; Picard, Nicolas; Wiser, Susan; Zhou, Mo; Alberti, Giorgio; Schulze, Ernst-Detlef; McGuire, A David; Bozzato, Fabio; Pretzsch, Hans; de-Miguel, Sergio; Paquette, Alain; Hérault, Bruno; Scherer-Lorenzen, Michael; Barrett, Christopher B; Glick, Henry B; Hengeveld, Geerten M; Nabuurs, Gert-Jan; Pfautsch, Sebastian; Viana, Helder; Vibrans, Alexander C; Ammer, Christian; Schall, Peter; Verbyla, David; Tchebakova, Nadja; Fischer, Markus; Watson, James V; Chen, Han Y H; Lei, Xiangdong; Schelhaas, Mart-Jan; Lu, Huicui; Gianelle, Damiano; Parfenova, Elena I; Salas, Christian; Lee, Eungul; Lee, Boknam; Kim, Hyun Seok; Bruelheide, Helge; Coomes, David A; Piotto, Daniel; Sunderland, Terry; Schmid, Bernhard; Gourlet-Fleury, Sylvie; Sonké, Bonaventure; Tavani, Rebecca; Zhu, Jun; Brandl, Susanne; Vayreda, Jordi; Kitahara, Fumiaki; Searle, Eric B; Neldner, Victor J; Ngugi, Michael R; Baraloto, Christopher; Frizzera, Lorenzo; Bałazy, Radomir; Oleksyn, Jacek; Zawiła-Niedźwiecki, Tomasz; Bouriaud, Olivier; Bussotti, Filippo; Finér, Leena; Jaroszewicz, Bogdan; Jucker, Tommaso; Valladares, Fernando; Jagodzinski, Andrzej M; Peri, Pablo L; Gonmadje, Christelle; Marthy, William; O'Brien, Timothy; Martin, Emanuel H; Marshall, Andrew R; Rovero, Francesco; Bitariho, Robert; Niklaus, Pascal A; Alvarez-Loayza, Patricia; Chamuya, Nurdin; Valencia, Renato; Mortier, Frédéric; Wortel, Verginia; Engone-Obiang, Nestor L; Ferreira, Leandro V; Odeke, David E; Vasquez, Rodolfo M; Lewis, Simon L; Reich, Peter B

    2016-10-14

    The biodiversity-productivity relationship (BPR) is foundational to our understanding of the global extinction crisis and its impacts on ecosystem functioning. Understanding BPR is critical for the accurate valuation and effective conservation of biodiversity. Using ground-sourced data from 777,126 permanent plots, spanning 44 countries and most terrestrial biomes, we reveal a globally consistent positive concave-down BPR, showing that continued biodiversity loss would result in an accelerating decline in forest productivity worldwide. The value of biodiversity in maintaining commercial forest productivity alone-US$166 billion to 490 billion per year according to our estimation-is more than twice what it would cost to implement effective global conservation. This highlights the need for a worldwide reassessment of biodiversity values, forest management strategies, and conservation priorities.

  13. How to manage oak forests for acorn production

    SciTech Connect

    Johnson, P.S.

    1994-03-01

    Oak forests are life support systems for the many animals that live in them. Acorns, a staple product of oak forests, are eaten by many species of birds and mammals including deer, bear, squirrels, mice, rabbits, foxes, raccoons, grackles, turkey, grouse, quail, blue jays, woodpeckers, and water-fowl. The population and health and wildlife often rise, and fall with the cyclic production of acorns. Acorns' importance to wildlife is related to several factors including their widespread occurrence, palatability, nutritiousness, and availability during the critical fall and winter period.

  14. Why do forest products become less available?A pan-tropical comparison of drivers of forest-resource degradation

    NASA Astrophysics Data System (ADS)

    Hermans-Neumann, Kathleen; Gerstner, Katharina; Geijzendorffer, Ilse R.; Herold, Martin; Seppelt, Ralf; Wunder, Sven

    2016-12-01

    Forest products provide an important source of income and wellbeing for rural smallholder communities across the tropics. Although tropical forest products frequently become over-exploited, only few studies explicitly address the dynamics of degradation in response to socio-economic drivers. Our study addresses this gap by analyzing the factors driving changes in tropical forest products in the perception of rural smallholder communities. Using the poverty and environment network global dataset, we studied recently perceived trends of forest product availability considering firewood, charcoal, timber, food, medicine, forage and other forest products. We looked at a pan-tropical sample of 233 villages with forest access. Our results show that 90% of the villages experienced declining availability of forest resources over the last five years according to the informants. Timber and fuelwood together with forest foods were featured as the most strongly affected, though with marked differences across continents. In contrast, availability of at least one main forest product was perceived to increase in only 39% of the villages. Furthermore, the growing local use of forest resources is seen as the main culprit for the decline. In villages with both growing forest resource use and immigration—vividly illustrating demographic pressures—the strongest forest resources degradation was observed. Conversely, villages with little or no population growth and a decreased use of forest resources were most likely to see significant forest-resource increases. Further, villages are less likely to perceive resource declines when local communities own a significant share of forest area. Our results thus suggest that perceived resource declines have only exceptionally triggered adaptations in local resource-use and management patterns that would effectively deal with scarcity. Hence, at the margin this supports neo-Malthusian over neo-Boserupian explanations of local resource

  15. Non-Timber Forest Products' Marketing in Nigeria. A Case Study of Osun State

    ERIC Educational Resources Information Center

    Aiyeloja, Adedapo Ayo; Ajewole, Opeyemi Isaac

    2006-01-01

    Research on markets and marketing of some non-timber forest products (NTFPs) was carried out in selected locations of Osun State. The NTFPs considered are chewing sticks such as "Massularia acuminata" and bush meat like "Thryonomys swinderianus", representing both the flora and fauna aspects of NTFPs, respectively. Five Local…

  16. California`s forest products industry: 1994. Forest Service resource bulletin

    SciTech Connect

    Ward, F.R.

    1997-06-01

    This report presents the findings of a survey of primary forest products industries in California for 1994. The survey included the following sectors: lumber; veneer; pulp and board; shake and shingle; export; and post, pole, and characteristics of the industry, nature and flow of logs consumed, and disposition of mill residues.

  17. Oregon`s forest products industry: 1994. Forest Service resource bulletin

    SciTech Connect

    Ward, F.R.

    1997-03-01

    This report presents the findings of a survey of primary forest products industries in Oregon for 1994. The survey included the following sectors: lumber; veneer; pulp and board; shake and shingle; export; and post, pole, and piling. Tables, presented by sector and for the industry as a whole, include characteristics of the industry, nature and flow of logs consumed, and disposition of mill residues.

  18. Past and Prospective Carbon Stocks of United States Forests: Implications for Research Priorities and Mitigation Policies

    NASA Astrophysics Data System (ADS)

    Birdsey, R.; Pan, Y.; McGuire, A. D.; Zhang, F.; Chen, J. M.

    2014-12-01

    United States forests and wood products have been a significant and persistent carbon sink of 100-200 million tons annually since 1950, currently offsetting about 12% of U.S. emissions of CO2. This carbon sink is caused by recovery of forest C stocks following timber harvest and abandonment of agricultural land over the last 150 years, and more recently the growth-enhancing effects of N deposition, increasing atmospheric CO2, and climate variability. The forest carbon sink would have been significantly larger if not for continued losses of forest to other land uses such as urban development, and increasing impacts from natural disturbances such as fire and insect outbreaks. Projections of the future U.S. C sink have raised concerns that it may disappear in a few decades because of slower growth, continued losses of forest area, and increasing demand for timber products especially bioenergy. However, continuing atmospheric and climate changes may delay this projected decline in the sink strength for another 50 years or longer. Research is urgently needed to improve projections of land-use changes and demand for timber, quantify the large-scale effects of atmospheric change and climate variability, and develop modeling approaches that can effectively integrate these multiple factors. Policy decisions to meet emissions reduction targets are partially dependent on assumptions about the magnitude of the future forest carbon sink; therefore, it is important to have convincing projections about how these various driving factors will affect forests in the future.

  19. Managing coarse woody debris in forests of the Rocky Mountains. Forest Service research paper

    SciTech Connect

    Graham, R.T.; Harvey, A.E.; Jurgensen, M.F.; Jain, T.B.; Tonn, J.R.

    1994-09-01

    Recommendations for managing coarse woody debris after timber harvest were developed for 14 habitat types, ranging from ponderosa pine (Pinus ponderosa) habitat types of Arizona to subalpine fir (Abis lasiocarpa) habitat types of western Montana. Ectomycorrhizae were used as a bioindicator of health, productive forest soils. Undisturbed stands were studied to determine the optimum amounts of organic material for ectomycorrhizal activity. The management recommendations are intentionally conservative to ensure that enough organic matter is left after timber harvest to maintain long-term forest productivity.

  20. Research Productivity and Academics' Conceptions of Research

    ERIC Educational Resources Information Center

    Brew, Angela; Boud, David; Namgung, Sang Un; Lucas, Lisa; Crawford, Karin

    2016-01-01

    This paper asks the question: do people with different levels of research productivity and identification as a researcher think of research differently? It discusses a study that differentiated levels of research productivity among English and Australian academics working in research-intensive environments in three broad discipline areas: science,…

  1. Nut Production in Bertholletia excelsa across a Logged Forest Mosaic: Implications for Multiple Forest Use

    PubMed Central

    Rockwell, Cara A.; Guariguata, Manuel R.; Menton, Mary; Arroyo Quispe, Eriks; Quaedvlieg, Julia; Warren-Thomas, Eleanor; Fernandez Silva, Harol; Jurado Rojas, Edwin Eduardo; Kohagura Arrunátegui, José Andrés Hideki; Meza Vega, Luis Alberto; Revilla Vera, Olivia; Valera Tito, Jonatan Frank; Villarroel Panduro, Betxy Tabita; Yucra Salas, Juan José

    2015-01-01

    Although many examples of multiple-use forest management may be found in tropical smallholder systems, few studies provide empirical support for the integration of selective timber harvesting with non-timber forest product (NTFP) extraction. Brazil nut (Bertholletia excelsa, Lecythidaceae) is one of the world’s most economically-important NTFP species extracted almost entirely from natural forests across the Amazon Basin. An obligate out-crosser, Brazil nut flowers are pollinated by large-bodied bees, a process resulting in a hard round fruit that takes up to 14 months to mature. As many smallholders turn to the financial security provided by timber, Brazil nut fruits are increasingly being harvested in logged forests. We tested the influence of tree and stand-level covariates (distance to nearest cut stump and local logging intensity) on total nut production at the individual tree level in five recently logged Brazil nut concessions covering about 4000 ha of forest in Madre de Dios, Peru. Our field team accompanied Brazil nut harvesters during the traditional harvest period (January-April 2012 and January-April 2013) in order to collect data on fruit production. Three hundred and ninety-nine (approximately 80%) of the 499 trees included in this study were at least 100 m from the nearest cut stump, suggesting that concessionaires avoid logging near adult Brazil nut trees. Yet even for those trees on the edge of logging gaps, distance to nearest cut stump and local logging intensity did not have a statistically significant influence on Brazil nut production at the applied logging intensities (typically 1–2 timber trees removed per ha). In one concession where at least 4 trees ha-1 were removed, however, the logging intensity covariate resulted in a marginally significant (0.09) P value, highlighting a potential risk for a drop in nut production at higher intensities. While we do not suggest that logging activities should be completely avoided in Brazil nut rich

  2. Nut Production in Bertholletia excelsa across a Logged Forest Mosaic: Implications for Multiple Forest Use.

    PubMed

    Rockwell, Cara A; Guariguata, Manuel R; Menton, Mary; Arroyo Quispe, Eriks; Quaedvlieg, Julia; Warren-Thomas, Eleanor; Fernandez Silva, Harol; Jurado Rojas, Edwin Eduardo; Kohagura Arrunátegui, José Andrés Hideki; Meza Vega, Luis Alberto; Revilla Vera, Olivia; Quenta Hancco, Roger; Valera Tito, Jonatan Frank; Villarroel Panduro, Betxy Tabita; Yucra Salas, Juan José

    2015-01-01

    Although many examples of multiple-use forest management may be found in tropical smallholder systems, few studies provide empirical support for the integration of selective timber harvesting with non-timber forest product (NTFP) extraction. Brazil nut (Bertholletia excelsa, Lecythidaceae) is one of the world's most economically-important NTFP species extracted almost entirely from natural forests across the Amazon Basin. An obligate out-crosser, Brazil nut flowers are pollinated by large-bodied bees, a process resulting in a hard round fruit that takes up to 14 months to mature. As many smallholders turn to the financial security provided by timber, Brazil nut fruits are increasingly being harvested in logged forests. We tested the influence of tree and stand-level covariates (distance to nearest cut stump and local logging intensity) on total nut production at the individual tree level in five recently logged Brazil nut concessions covering about 4000 ha of forest in Madre de Dios, Peru. Our field team accompanied Brazil nut harvesters during the traditional harvest period (January-April 2012 and January-April 2013) in order to collect data on fruit production. Three hundred and ninety-nine (approximately 80%) of the 499 trees included in this study were at least 100 m from the nearest cut stump, suggesting that concessionaires avoid logging near adult Brazil nut trees. Yet even for those trees on the edge of logging gaps, distance to nearest cut stump and local logging intensity did not have a statistically significant influence on Brazil nut production at the applied logging intensities (typically 1-2 timber trees removed per ha). In one concession where at least 4 trees ha-1 were removed, however, the logging intensity covariate resulted in a marginally significant (0.09) P value, highlighting a potential risk for a drop in nut production at higher intensities. While we do not suggest that logging activities should be completely avoided in Brazil nut rich

  3. 29 CFR 780.1016 - Use of evergreens and forest products.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 29 Labor 3 2010-07-01 2010-07-01 false Use of evergreens and forest products. 780.1016 Section 780... Labor Provisions Under Section 13(d) Requirements for Exemption § 780.1016 Use of evergreens and forest products. Harvesting of evergreens and other forest products is exempt only when these products will...

  4. 29 CFR 780.1016 - Use of evergreens and forest products.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 29 Labor 3 2013-07-01 2013-07-01 false Use of evergreens and forest products. 780.1016 Section 780... Labor Provisions Under Section 13(d) Requirements for Exemption § 780.1016 Use of evergreens and forest products. Harvesting of evergreens and other forest products is exempt only when these products will...

  5. 29 CFR 780.1016 - Use of evergreens and forest products.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 29 Labor 3 2011-07-01 2011-07-01 false Use of evergreens and forest products. 780.1016 Section 780... Labor Provisions Under Section 13(d) Requirements for Exemption § 780.1016 Use of evergreens and forest products. Harvesting of evergreens and other forest products is exempt only when these products will...

  6. 29 CFR 780.1016 - Use of evergreens and forest products.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 29 Labor 3 2014-07-01 2014-07-01 false Use of evergreens and forest products. 780.1016 Section 780... Labor Provisions Under Section 13(d) Requirements for Exemption § 780.1016 Use of evergreens and forest products. Harvesting of evergreens and other forest products is exempt only when these products will...

  7. 29 CFR 780.1016 - Use of evergreens and forest products.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 29 Labor 3 2012-07-01 2012-07-01 false Use of evergreens and forest products. 780.1016 Section 780... Labor Provisions Under Section 13(d) Requirements for Exemption § 780.1016 Use of evergreens and forest products. Harvesting of evergreens and other forest products is exempt only when these products will...

  8. Assessment of carbon pools in production forest, Pahang, Malaysia

    NASA Astrophysics Data System (ADS)

    Azian, M.; Nizam, M. S.; Samsudin, M.; Ismail, P.

    2016-11-01

    Forest is one of the main sources of carbon stock. Forest plays a key role in sustainable management by providing different aspects of forest ecosystem such as source of timber products, provide of clean water, food sources, etc. A study was conducted to assess carbon pools in selected production forest of Pahang, Malaysia. There are five main types of carbon pools that are recognized available in the forest, i.e. aboveground biomass (AGB), belowground biomass (BGB), deadwood, litter and soil; that these components of carbon pools can accumulate and release carbon into the atmosphere. Five sites with different years of logging period representing status of the forest were selected (i.e. before logging (PU), immediate after logging (P0), after 10 (P10), 20 (P20) and 30 (P30) years of logging). Twenty plots of 0.25 ha (50 m × 50 m) each were established with a total sampling area of 1.0 ha at each site. All trees with ≥10 cm diameter at breast height (dbh) were tagged, identified and measured. Soil at 0-30 cm, litter and dead wood were sampled and collected in every each of sub-plots to determine and assess carbon stocks within sites. The results indicated that AGB carbon had highest portion of carbon compared to soil, BGB, deadwood and litter, which comprised about 63% of the total carbon pools. It was followed by soil and BGB that comprised about 22% and 13%, respectively. Deadwood and litter contributes the same percentage which is about 1%. In terms of status of the forest, AGB contained the highest carbon which is range from 110.49 tC ha-1 to 164.49 tC ha-1 compared with soil (33.72 tC ha-1 to 68.51 tC ha-1), BGB tC ha-1 to 34 tC ha-1), deadwood (1.57 tC ha-1 to 5.55 tC ha-1) and litter (1.42 tC ha-1 to 2.19 tC ha-1). Results from this study will be very helpful as baseline of carbon storage in different status of forest from before harvesting to logged-over forest and the impact of harvesting on the carbon stock in Pahang and Peninsular Malaysia as a whole.

  9. 77 FR 17524 - Roseburg Forest Products, Composite Panels Division, Missoula, MT; Notice of Affirmative...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-26

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF LABOR Employment and Training Administration Roseburg Forest Products, Composite Panels Division, Missoula, MT... workers and former workers of Roseburg Forest Products, Composite Panels Division, Missoula,...

  10. 77 FR 35061 - Roseburg Forest Products Composite Panels Division Missoula, Montana; Notice of Negative...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-12

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF LABOR Employment and Training Administration Roseburg Forest Products Composite Panels Division Missoula, Montana... former workers of Roseburg Forest Products, Composite Panels Division, Missoula, Montana (subject...

  11. World supply and demand for forests products

    SciTech Connect

    Lyke, J.; Brooks, D.J.

    1995-10-01

    This article summarizes the forestry issues of the future including increasing scarcity of traditional raw material with resulting substitution and technological change; changes in consumer tastes and preferences, including greater attention to the environmental consequences of production and consumption; and the incorporation of environmental considerations in economic and trade policies. The importance of fuelwood is highlighted in the figures. 14 refs., 3 figs.

  12. Monitoring Regional Forest Disturbances across the US with Near Real Time MODIS NDVI Products included in the ForWarn Forest Threat Early Warning System

    NASA Technical Reports Server (NTRS)

    Spruce, Joseph; Hargrove, William W.; Gasser, Gerald; Norman, Steve

    2013-01-01

    U.S. forests occupy approx.1/3 of total land area (approx. 304 million ha). Since 2000, a growing number of regionally evident forest disturbances have occurred due to abiotic and biotic agents. Regional forest disturbances can threaten human life and property, bio-diversity and water supplies. Timely regional forest disturbance monitoring products are needed to aid forest health management work. Near Real Time (NRT) twice daily MODIS NDVI data provide a means to monitor U.S. regional forest disturbances every 8 days. Since 2010, these NRT forest change products have been produced and posted on the US Forest Service ForWarn Early Warning System for Forest Threats.

  13. New products made with lignocellulosic nanofibers from Brazilian amazon forest

    NASA Astrophysics Data System (ADS)

    Bufalino, L.; Mendes, L. M.; Tonoli, G. H. D.; Rodrigues, A.; Fonseca, A.; Cunha, P. I.; Marconcini, J. M.

    2014-08-01

    The biodiversity of the Amazon forest is undoubtedly rich; hence there is considerable variety of plant fibers regarding their morphological, chemical and structural properties. The legal exploration of the Brazilian Amazon is based on sustainable management techniques, but the generation of a relevant amount of plant wastes still cant be avoided. The correct destination of such materials is a challenge that Brazilian companies have to face. In this context, the National Council of Science and Technology (CNPq) promoted the creation of investigation nets on sustainability of Brazilian agribusiness. The Brazilian Net on Lignocellulosic Composites and Nanocomposites was then created, with partnership between several national and international research institutions. Until the moment, the results showed that Amazon plant fibers that are discarded as residues have great potential to nanofiber production. Nanopapers with considerable high mechanical and physical strength, proper opacity and great crystalline index were produced by using a clean and simple mechanical method. Those materials are candidates to several uses such as packaging, substrates transparent conductive films, gas barrier films, solar cells and e-papers.

  14. Interpreting forest biome productivity and cover utilizing nested scales of image resolution and biogeographical analysis

    NASA Technical Reports Server (NTRS)

    Iverson, Louis R.; Cook, Elizabeth A.; Graham, Robin L.; Olson, Jerry S.; Frank, Thomas D.; Ying, KE

    1988-01-01

    The objective was to relate spectral imagery of varying resolution with ground-based data on forest productivity and cover, and to create models to predict regional estimates of forest productivity and cover with a quantifiable degree of accuracy. A three stage approach was outlined. In the first stage, a model was developed relating forest cover or productivity to TM surface reflectance values (TM/FOREST models). The TM/FOREST models were more accurate when biogeographic information regarding the landscape was either used to stratigy the landscape into more homogeneous units or incorporated directly into the TM/FOREST model. In the second stage, AVHRR/FOREST models that predicted forest cover and productivity on the basis of AVHRR band values were developed. The AVHRR/FOREST models had statistical properties similar to or better than those of the TM/FOREST models. In the third stage, the regional predictions were compared with the independent U.S. Forest Service (USFS) data. To do this regional forest cover and forest productivity maps were created using AVHRR scenes and the AVHRR/FOREST models. From the maps the county values of forest productivity and cover were calculated. It is apparent that the landscape has a strong influence on the success of the approach. An approach of using nested scales of imagery in conjunction with ground-based data can be successful in generating regional estimates of variables that are functionally related to some variable a sensor can detect.

  15. Structural diversity promotes productivity of mixed, uneven-aged forests in southwestern Germany.

    PubMed

    Dănescu, Adrian; Albrecht, Axel T; Bauhus, Jürgen

    2016-10-01

    Forest diversity-productivity relationships have been intensively investigated in recent decades. However, few studies have considered the interplay between species and structural diversity in driving productivity. We analyzed these factors using data from 52 permanent plots in southwestern Germany with more than 53,000 repeated tree measurements. We used basal area increment as a proxy for productivity and hypothesized that: (1) structural diversity would increase tree and stand productivity, (2) diversity-productivity relationships would be weaker for species diversity than for structural diversity, and (3) species diversity would also indirectly impact stand productivity via changes in size structure. We measured diversity using distance-independent indices. We fitted separate linear mixed-effects models for fir, spruce and beech at the tree level, whereas at the stand level we pooled all available data. We tested our third hypothesis using structural equation modeling. Structural and species diversity acted as direct and independent drivers of stand productivity, with structural diversity being a slightly better predictor. Structural diversity, but not species diversity, had a significant, albeit asymmetric, effect on tree productivity. The functioning of structurally diverse, mixed forests is influenced by both structural and species diversity. These sources of trait diversity contribute to increased vertical stratification and crown plasticity, which in turn diminish competitive interferences and lead to more densely packed canopies per unit area. Our research highlights the positive effects of species diversity and structural diversity on forest productivity and ecosystem dynamics.

  16. Forests and ozone: productivity, carbon storage, and feedbacks

    PubMed Central

    Wang, Bin; Shugart, Herman H.; Shuman, Jacquelyn K.; Lerdau, Manuel T.

    2016-01-01

    Tropospheric ozone is a serious air-pollutant, with large impacts on plant function. This study demonstrates that tropospheric ozone, although it damages plant metabolism, does not necessarily reduce ecosystem processes such as productivity or carbon sequestration because of diversity change and compensatory processes at the community scale ameliorate negative impacts at the individual level. This study assesses the impact of ozone on forest composition and ecosystem dynamics with an individual-based gap model that includes basic physiology as well as species-specific metabolic properties. Elevated tropospheric ozone leads to no reduction of forest productivity and carbon stock and to increased isoprene emissions, which result from enhanced dominance by isoprene-emitting species (which tolerate ozone stress better than non-emitters). This study suggests that tropospheric ozone may not diminish forest carbon sequestration capacity. This study also suggests that, because of the often positive relationship between isoprene emission and ozone formation, there is a positive feedback loop between forest communities and ozone, which further aggravates ozone pollution. PMID:26899381

  17. Forests and ozone: productivity, carbon storage, and feedbacks.

    PubMed

    Wang, Bin; Shugart, Herman H; Shuman, Jacquelyn K; Lerdau, Manuel T

    2016-02-22

    Tropospheric ozone is a serious air-pollutant, with large impacts on plant function. This study demonstrates that tropospheric ozone, although it damages plant metabolism, does not necessarily reduce ecosystem processes such as productivity or carbon sequestration because of diversity change and compensatory processes at the community scale ameliorate negative impacts at the individual level. This study assesses the impact of ozone on forest composition and ecosystem dynamics with an individual-based gap model that includes basic physiology as well as species-specific metabolic properties. Elevated tropospheric ozone leads to no reduction of forest productivity and carbon stock and to increased isoprene emissions, which result from enhanced dominance by isoprene-emitting species (which tolerate ozone stress better than non-emitters). This study suggests that tropospheric ozone may not diminish forest carbon sequestration capacity. This study also suggests that, because of the often positive relationship between isoprene emission and ozone formation, there is a positive feedback loop between forest communities and ozone, which further aggravates ozone pollution.

  18. Forests and ozone: productivity, carbon storage, and feedbacks

    NASA Astrophysics Data System (ADS)

    Wang, Bin; Shugart, Herman H.; Shuman, Jacquelyn K.; Lerdau, Manuel T.

    2016-02-01

    Tropospheric ozone is a serious air-pollutant, with large impacts on plant function. This study demonstrates that tropospheric ozone, although it damages plant metabolism, does not necessarily reduce ecosystem processes such as productivity or carbon sequestration because of diversity change and compensatory processes at the community scale ameliorate negative impacts at the individual level. This study assesses the impact of ozone on forest composition and ecosystem dynamics with an individual-based gap model that includes basic physiology as well as species-specific metabolic properties. Elevated tropospheric ozone leads to no reduction of forest productivity and carbon stock and to increased isoprene emissions, which result from enhanced dominance by isoprene-emitting species (which tolerate ozone stress better than non-emitters). This study suggests that tropospheric ozone may not diminish forest carbon sequestration capacity. This study also suggests that, because of the often positive relationship between isoprene emission and ozone formation, there is a positive feedback loop between forest communities and ozone, which further aggravates ozone pollution.

  19. Decomposition of forest products buried in landfills

    SciTech Connect

    Wang, Xiaoming; Padgett, Jennifer M.; Powell, John S.; Barlaz, Morton A.

    2013-11-15

    Highlights: • This study tracked chemical changes of wood and paper in landfills. • A decomposition index was developed to quantify carbohydrate biodegradation. • Newsprint biodegradation as measured here is greater than previous reports. • The field results correlate well with previous laboratory measurements. - Abstract: The objective of this study was to investigate the decomposition of selected wood and paper products in landfills. The decomposition of these products under anaerobic landfill conditions results in the generation of biogenic carbon dioxide and methane, while the un-decomposed portion represents a biogenic carbon sink. Information on the decomposition of these municipal waste components is used to estimate national methane emissions inventories, for attribution of carbon storage credits, and to assess the life-cycle greenhouse gas impacts of wood and paper products. Hardwood (HW), softwood (SW), plywood (PW), oriented strand board (OSB), particleboard (PB), medium-density fiberboard (MDF), newsprint (NP), corrugated container (CC) and copy paper (CP) were buried in landfills operated with leachate recirculation, and were excavated after approximately 1.5 and 2.5 yr. Samples were analyzed for cellulose (C), hemicellulose (H), lignin (L), volatile solids (VS), and organic carbon (OC). A holocellulose decomposition index (HOD) and carbon storage factor (CSF) were calculated to evaluate the extent of solids decomposition and carbon storage. Samples of OSB made from HW exhibited cellulose plus hemicellulose (C + H) loss of up to 38%, while loss for the other wood types was 0–10% in most samples. The C + H loss was up to 81%, 95% and 96% for NP, CP and CC, respectively. The CSFs for wood and paper samples ranged from 0.34 to 0.47 and 0.02 to 0.27 g OC g{sup −1} dry material, respectively. These results, in general, correlated well with an earlier laboratory-scale study, though NP and CC decomposition measured in this study were higher than

  20. Decomposition of forest products buried in landfills.

    PubMed

    Wang, Xiaoming; Padgett, Jennifer M; Powell, John S; Barlaz, Morton A

    2013-11-01

    The objective of this study was to investigate the decomposition of selected wood and paper products in landfills. The decomposition of these products under anaerobic landfill conditions results in the generation of biogenic carbon dioxide and methane, while the un-decomposed portion represents a biogenic carbon sink. Information on the decomposition of these municipal waste components is used to estimate national methane emissions inventories, for attribution of carbon storage credits, and to assess the life-cycle greenhouse gas impacts of wood and paper products. Hardwood (HW), softwood (SW), plywood (PW), oriented strand board (OSB), particleboard (PB), medium-density fiberboard (MDF), newsprint (NP), corrugated container (CC) and copy paper (CP) were buried in landfills operated with leachate recirculation, and were excavated after approximately 1.5 and 2.5yr. Samples were analyzed for cellulose (C), hemicellulose (H), lignin (L), volatile solids (VS), and organic carbon (OC). A holocellulose decomposition index (HOD) and carbon storage factor (CSF) were calculated to evaluate the extent of solids decomposition and carbon storage. Samples of OSB made from HW exhibited cellulose plus hemicellulose (C+H) loss of up to 38%, while loss for the other wood types was 0-10% in most samples. The C+H loss was up to 81%, 95% and 96% for NP, CP and CC, respectively. The CSFs for wood and paper samples ranged from 0.34 to 0.47 and 0.02 to 0.27gOCg(-1) dry material, respectively. These results, in general, correlated well with an earlier laboratory-scale study, though NP and CC decomposition measured in this study were higher than previously reported.

  1. Nitrogen dynamics in managed boreal forests: Recent advances and future research directions.

    PubMed

    Sponseller, Ryan A; Gundale, Michael J; Futter, Martyn; Ring, Eva; Nordin, Annika; Näsholm, Torgny; Laudon, Hjalmar

    2016-02-01

    Nitrogen (N) availability plays multiple roles in the boreal landscape, as a limiting nutrient to forest growth, determinant of terrestrial biodiversity, and agent of eutrophication in aquatic ecosystems. We review existing research on forest N dynamics in northern landscapes and address the effects of management and environmental change on internal cycling and export. Current research foci include resolving the nutritional importance of different N forms to trees and establishing how tree-mycorrhizal relationships influence N limitation. In addition, understanding how forest responses to external N inputs are mediated by above- and belowground ecosystem compartments remains an important challenge. Finally, forestry generates a mosaic of successional patches in managed forest landscapes, with differing levels of N input, biological demand, and hydrological loss. The balance among these processes influences the temporal patterns of stream water chemistry and the long-term viability of forest growth. Ultimately, managing forests to keep pace with increasing demands for biomass production, while minimizing environmental degradation, will require multi-scale and interdisciplinary perspectives on landscape N dynamics.

  2. Oregon`s forest products industry: 1992. Forest Service resource bulletin

    SciTech Connect

    Ward, F.R.

    1995-03-01

    The report presents the findings of a survey of primary forest products industries in Oregon for 1992. The survey included the following sectors; lumber; veneer and plywood; pulp and board; shake and shingle; export; and post, pole, and piling. Tables presented by sector and for the industry as a whole, include characteristics of the industry, nature and flow of logs consumed, and disposition of mill residues.

  3. California`s forest products industry: 1992. Forest Service resource bulletin

    SciTech Connect

    Ward, F.R.

    1995-03-01

    The report presents the findings of a survey of primary forest products industries in California for 1992. The survey included the following sectors: Lumber, pulp and board; shake and shingle; export; and post, pole, and piling. Veneer and plywood mills are not included because they could not be presented without disclosng critical details. Tables, presented by sector and for the industry as a whole, include characteristics of the industry, nature and flow of logs consumed, and disposition of mill residence.

  4. Measuring forest structure along productivity gradients in the Canadian boreal with small-footprint Lidar.

    PubMed

    Bolton, Douglas K; Coops, Nicholas C; Wulder, Michael A

    2013-08-01

    The structure and productivity of boreal forests are key components of the global carbon cycle and impact the resources and habitats available for species. With this research, we characterized the relationship between measurements of forest structure and satellite-derived estimates of gross primary production (GPP) over the Canadian boreal. We acquired stand level indicators of canopy cover, canopy height, and structural complexity from nearly 25,000 km of small-footprint discrete return Light Detection and Ranging (Lidar) data and compared these attributes to GPP estimates derived from the MODerate resolution Imaging Spectroradiometer (MODIS). While limited in our capacity to control for stand age, we removed recently disturbed and managed forests using information on fire history, roads, and anthropogenic change. We found that MODIS GPP was strongly linked to Lidar-derived canopy cover (r = 0.74, p < 0.01), however was only weakly related to Lidar-derived canopy height and structural complexity as these attributes are largely a function of stand age. A relationship was apparent between MODIS GPP and the maximum sampled heights derived from Lidar as growth rates and resource availability likely limit tree height in the prolonged absence of disturbance. The most structurally complex stands, as measured by the coefficient of variation of Lidar return heights, occurred where MODIS GPP was highest as productive boreal stands are expected to contain a wider range of tree heights and transition to uneven-aged structures faster than less productive stands. While MODIS GPP related near-linearly to Lidar-derived canopy cover, the weaker relationships to Lidar-derived canopy height and structural complexity highlight the importance of stand age in determining the structure of boreal forests. We conclude that an improved quantification of how both productivity and disturbance shape stand structure is needed to better understand the current state of boreal forests in

  5. Biogeographical and taxonomic biases in tropical forest fragmentation research.

    PubMed

    Deikumah, Justus P; McAlpine, Clive A; Maron, Martine

    2014-12-01

    Despite several decades of research on the effects of fragmentation and habitat change on biodiversity, there remain strong biases in the geographical regions and taxonomic species studied. The knowledge gaps resulting from these biases are of particular concern if the forests most threatened with modification are also those for which the effects of such change are most poorly understood. To quantify the nature and magnitude of such biases, we conducted a systematic review of the published literature on forest fragmentation in the tropics for the period 1980-2012. Studies included focused on any type of response of single species, communities, or assemblages of any taxonomic group to tropical forest fragmentation and on fragmentation-related changes to forests. Of the 853 studies we found in the SCOPUS database, 64% were conducted in the Neotropics, 13% in Asia, 10% in the Afrotropics, and 5% in Australasia. Thus, although the Afrotropics is subject to the highest rates of deforestation globally, it was the most disproportionately poorly studied biome. Significant taxonomic biases were identified. Of the taxonomic groups considered, herpetofauna was the least studied in the tropics, particularly in Africa. Research examining patterns of species distribution was by far the most common type (72%), and work focused on ecological processes (28%) was rare in all biomes, but particularly in the Afrotropics and for fauna. We suggest research efforts be directed toward less-studied biogeographic regions, particularly where the threat of forest fragmentation continues to be high. Increased research investment in the Afrotropics will be important to build knowledge of threats and inform responses in a region where almost no efforts to restore its fragmented landscapes have yet begun and forest protection is arguably most tenuous.

  6. Old growth in northwestern California National Forests. Forest Service research paper

    SciTech Connect

    Beardsley, D.; Warbington, R.

    1996-06-01

    This report estimates old-growth forest area and summarizes stand characteristics of old growth in northwestern California National Forests by forest type. Old-growth definitions for each forest type are used.

  7. Sentinel Mission: Forest Fire Products Evaluation over China

    NASA Astrophysics Data System (ADS)

    Garcia, M.; Sanz, J.; Salvador, P.; Molina, V.; Cassanova, J.-P.; Qin, Xianlin

    2016-08-01

    Sentinel-2a and Sentinel-3a were launch the 23 June 2015 and 16 February 2016 respectively. These two platforms constitute a great improvement in the surface monitoring, especially in forest fires emergency management, evaluation and recovery.The multispectral sensor on board Sentinel-2a is a perfect tool to delineate burnt areas and identify severity with great spatial and temporal resolution while the surface thermal information provided by Sea and Land Surface Temperature Radiometer (SLSTR) on board Sentinel-3a constitute a source of hotspots. Both platforms will be complemented with their respective twins Sentinel-2b and Sentinel-3b in order to improve temporal resolution.This work tries to evaluate the constellation capacity to provide reliable forest fires products over China by comparison with Earth Observing System (EOS) and Landsat constellation products.

  8. Changes in Forest Production, Biomass and Carbon: Results From the 2015 UN FAO Global Forest Resource Assessment

    NASA Astrophysics Data System (ADS)

    Navar, J.

    2015-12-01

    Forests are important sources of livelihoods to millions of people and contribute to national economic development of many countries. In addition, they are vital sources and sinks of carbon and contribute to the rate of climate change. The UN Food and Agriculture Organization has been collecting and presenting data on global forest resources and forest cover since 1948. This paper builds on data from FAO's 2015 Global Forest Resource Assessment (FRA) and presents information on growing stock, biomass, carbon stock, wood removals, and changes of forest area primarily designated for production and multiple use of the world's forests. Between 1990 and 2015, the total growing stock volume has increased in East Asia, Caribbean, Western and Central Asia, North America, Europe (including the Russian Federation), and Oceania with the highest relative increase in East Asia and the Caribbean. In all other subregions the total growing stock volume decreased. North and Central America, Europe and Asia report forest C stock increases while South America and Africa report strong decreases and Oceania reports stable forest C stocks. The annual rate of decrease of forest C stock weakened between 1990 and 2015. The total volume of annual wood removals including wood fuel removals increased between 1990 and 2011, but shows a remarkable decline during the 2008-2009 economic crisis. Forest areas designated for production purposes differ considerably between subregions. The percentage of production area out of total forest area ranges between 16 percent in South America and 53 percent in Europe. Globally about one quarter of the forest area is designated to multiple use forestry. The balance between biomass growth and removals shows considerable sub-regional differences and related implications for the sustainable use of forests.

  9. Varying rotation lengths in northern production forests: Implications for habitats provided by retention and production trees.

    PubMed

    Felton, Adam; Sonesson, Johan; Nilsson, Urban; Lämås, Tomas; Lundmark, Tomas; Nordin, Annika; Ranius, Thomas; Roberge, Jean-Michel

    2017-04-01

    Because of the limited spatial extent and comprehensiveness of protected areas, an increasing emphasis is being placed on conserving habitats which promote biodiversity within production forest. For this reason, alternative silvicultural programs need to be evaluated with respect to their implications for forest biodiversity, especially if these programs are likely to be adopted. Here we simulated the effect of varied rotation length and associated thinning regimes on habitat availability in Scots pine and Norway spruce production forests, with high and low productivity. Shorter rotation lengths reduced the contribution made by production trees (trees grown for industrial use) to the availability of key habitat features, while concurrently increasing the contribution from retention trees. The contribution of production trees to habitat features was larger for high productivity sites, than for low productivity sites. We conclude that shortened rotation lengths result in losses of the availability of habitat features that are key for biodiversity conservation and that increased retention practices may only partially compensate for this. Ensuring that conservation efforts better reflect the inherent variation in stand rotation lengths would help improve the maintenance of key forest habitats in production forests.

  10. Gender, Children and Research Productivity

    ERIC Educational Resources Information Center

    Stack, Steven

    2004-01-01

    The "productivity puzzle," or gender gap in research productivity, is often thought to be due, in part, to gendered child care responsibilities. The time, energy, and money devoted to child-rearing can reduce the research productivity of scholars, especially women. However, there is little systematic research on this issue. The present study…

  11. Net Primary Production of boreal forests in the Krasnoyarsk Territory

    NASA Astrophysics Data System (ADS)

    Larko, Alexander; Chernetskiy, Maxim; Shevyrnogov, Anatoly

    One of the most important characteristics used in the biosphere change control is net primary production dynamics. (NPP) NPP shows the amount of pure carbon fixed in plants for a definite time period, essentially, this indicator reflects the intensity of a carbon biochemical cycle. Being the main indicator of the ecosystem condition, NPP has great significance, since it is also an indicator of biosphere carbon flux intensity. Its use is important for ecological investigations, carbon cycle calculation and the distribution of natural recourses. Ground true ecosystems determine most of seasonal and annual changes in the atmospheric CO2 concentration. Satellite methods of investigation are known to be effectively used for the calculation of the global NPP distribution. In its turn, the study of boreal forest NPP dynamics is required to introduce clarity into global models and to understand their role in the carbon cycle. At present, there is a number of calculation models for obtaining NPP. In the given work, an estimate of NPP for boreal forests of the Krasnoyarsk Territory is made. For the calculation, the GloPEM model employing TERRA/MODIS and TOMS data has been used. The obtained data have been compared with satellite temperature and ground true climatic data and, also, with the forest vegetation maps. The maps contained data about the biomass amount and the forest species composition, which allowed one to obtain the results showing the nonuniformity of NPP distribution depending on the climatic conditions, species composition and the latitude of the objects under study.

  12. Impact of climate change on forests, forest products and the carbon cycle in the Congo Basin.

    NASA Astrophysics Data System (ADS)

    Kruijt, Bart; Jans, Wilma; Franssen, Wietse; Ludwig, Fulco

    2014-05-01

    Africa is widely seen as the continent most vulnerable to climate change. Current climate variability already has a large impact on the economies of developing countries. Large parts of African economies are highly climate sensitive, in particular agriculture, infrastructure and water sector. In this study we performed an analysis of climate change impacts in the Congo Basin on Forest ecosystem functioning and carbon storage. We emphasise the methodologies and validation involved in modelling the basin-wide carbon budgets. We also studied the potential shifts in broad classes of vegetation types, resulting from climate change. Finally, we compared annual productivity of the Congo forests with statistics of wood fuel and charcoal use for each of the countries in the region. The model simulations suggest that the region's forests will see increasing productivity under future climate, however, the effect of rising CO2 concentrations, stimulating growth, is highly uncertain. From these findings it follows that the potential in the region to implement UNFCCC-REDD+ projects is still very uncertain, but probably sustainable and feasible. The analysis shows that, averaged over 10 years, wood fuel and charcoal use amount to 50% and in some countries up to 100% or even more of the yearly vegetation carbon increase. These percentages generally increases with population density.

  13. [Research progress on molecular genetics of forest musk deer].

    PubMed

    Jie, Hang; Zheng, Cheng-li; Wang, Jian-ming; Feng, Xiao-lan; Zeng, De-jun; Zhao, Gui-jun

    2015-11-01

    Forest musk deer is one of the large-scale farming musk deer animals with the largest population at the same time. The male musk deer can secrete valuable medicines, which has high medicinal and economic value. Due to the loss of habitat and indiscriminate hunting, the numbers of wild population specie and the distribution have been drastically reduced. Therefore, in-depth understanding of the molecular genetics progress of forest musk deer will pave a way for musk deer protection and breeding. In this review, the progress associated with the molecular marker, genetic classification, artificial breeding, musk secretion and disease in past decades were reviewed, in order to provide a theoretical basis for subsequent molecular genetic researches in forest musk deer.

  14. Is the effect of forest structure on bird diversity modified by forest productivity?

    PubMed

    Verschuyl, Jacob P; Hansen, Andrew J; McWethy, David B; Sallabanks, Rex; Hutto, Richard L

    2008-07-01

    Currently, the most common strategy when managing forests for biodiversity at the landscape scale is to maintain structural complexity within stands and provide a variety of seral stages across landscapes. Advances in ecological theory reveal that biodiversity at continental scales is strongly influenced by available energy (i.e., climate factors relating to heat and light and primary productivity). This paper explores how available energy and forest structural complexity may interact to drive biodiversity at a regional scale. We hypothesized that bird species richness exhibits a hump-shaped relationship with energy at the regional scale of the northwestern United States. As a result, we hypothesized that the relationship between energy and richness within a landscape is positive in energy-limited landscapes and flat or decreasing in energy-rich landscapes. Additionally, we hypothesized that structural complexity explains less of the variation in species richness in energy-limited environments and more in energy-rich environments and that the slope of the relationship between structural complexity and richness is greatest in energy-rich environments. We sampled bird communities and vegetation across seral stages and biophysical settings at each of five landscapes arrayed across a productivity gradient from the Pacific Coast to the Rocky Mountains within the five northwestern states of the contiguous United States. We analyzed the response of richness to structural complexity and energy covariates at each landscape. We found that (1) richness had a hump-shaped relationship with available energy across the northwestern United States, (2) the landscape-scale relationships between energy and richness were positive or hump shaped in energy-limited locations and were flat or negative in energy-rich locations, (3) forest structural complexity explained more of the variation in bird species richness in energy-rich landscapes, and (4) the slope of the relationship between

  15. Under What Circumstances Do Wood Products from Native Forests Benefit Climate Change Mitigation?

    PubMed Central

    Keith, Heather; Lindenmayer, David; Macintosh, Andrew; Mackey, Brendan

    2015-01-01

    Climate change mitigation benefits from the land sector are not being fully realised because of uncertainty and controversy about the role of native forest management. The dominant policy view, as stated in the IPCC’s Fifth Assessment Report, is that sustainable forest harvesting yielding wood products, generates the largest mitigation benefit. We demonstrate that changing native forest management from commercial harvesting to conservation can make an important contribution to mitigation. Conservation of native forests results in an immediate and substantial reduction in net emissions relative to a reference case of commercial harvesting. We calibrated models to simulate scenarios of native forest management for two Australian case studies: mixed-eucalypt in New South Wales and Mountain Ash in Victoria. Carbon stocks in the harvested forest included forest biomass, wood and paper products, waste in landfill, and bioenergy that substituted for fossil fuel energy. The conservation forest included forest biomass, and subtracted stocks for the foregone products that were substituted by non-wood products or plantation products. Total carbon stocks were lower in harvested forest than in conservation forest in both case studies over the 100-year simulation period. We tested a range of potential parameter values reported in the literature: none could increase the combined carbon stock in products, slash, landfill and substitution sufficiently to exceed the increase in carbon stock due to changing management of native forest to conservation. The key parameters determining carbon stock change under different forest management scenarios are those affecting accumulation of carbon in forest biomass, rather than parameters affecting transfers among wood products. This analysis helps prioritise mitigation activities to focus on maximising forest biomass. International forest-related policies, including negotiations under the UNFCCC, have failed to recognize fully the mitigation

  16. Under What Circumstances Do Wood Products from Native Forests Benefit Climate Change Mitigation?

    PubMed

    Keith, Heather; Lindenmayer, David; Macintosh, Andrew; Mackey, Brendan

    2015-01-01

    Climate change mitigation benefits from the land sector are not being fully realised because of uncertainty and controversy about the role of native forest management. The dominant policy view, as stated in the IPCC's Fifth Assessment Report, is that sustainable forest harvesting yielding wood products, generates the largest mitigation benefit. We demonstrate that changing native forest management from commercial harvesting to conservation can make an important contribution to mitigation. Conservation of native forests results in an immediate and substantial reduction in net emissions relative to a reference case of commercial harvesting. We calibrated models to simulate scenarios of native forest management for two Australian case studies: mixed-eucalypt in New South Wales and Mountain Ash in Victoria. Carbon stocks in the harvested forest included forest biomass, wood and paper products, waste in landfill, and bioenergy that substituted for fossil fuel energy. The conservation forest included forest biomass, and subtracted stocks for the foregone products that were substituted by non-wood products or plantation products. Total carbon stocks were lower in harvested forest than in conservation forest in both case studies over the 100-year simulation period. We tested a range of potential parameter values reported in the literature: none could increase the combined carbon stock in products, slash, landfill and substitution sufficiently to exceed the increase in carbon stock due to changing management of native forest to conservation. The key parameters determining carbon stock change under different forest management scenarios are those affecting accumulation of carbon in forest biomass, rather than parameters affecting transfers among wood products. This analysis helps prioritise mitigation activities to focus on maximising forest biomass. International forest-related policies, including negotiations under the UNFCCC, have failed to recognize fully the mitigation

  17. Productivity of Northern Eurasian forests: Analysis of uncertainties

    NASA Astrophysics Data System (ADS)

    Shvidenko, Anatoly; Schepaschenko, Dmitry; McCallum, Ian

    2010-05-01

    Indicators of biological productivity of forests (live and dead biomass, net primary production, net and gross growth) are crucial for both assessment of the impacts of terrestrial ecosystems on major biogeochemical cycles and practice of sustainable forest management. However, different information and the diversity of methods used in the assessments of forests productivity cause substantial variation in reported estimates. The paper contains a systems analysis of the existing methods, their uncertainties, and a description of available information. With respect to Northern Eurasian forests, the major reasons for uncertainties could be categorized as following: (1) significant biases that are inherent in a number of important sources of available information (e.g., forest inventory data, results of measurements of some indicators in situ); (2) inadequacy and oversimplification of models of different types (empirical aggregations, process-based models); (3) lack of data for some regions; and (4) upscaling procedure of 'point' observations. Based on as comprehensive as possible adherence to the principles of systems analysis, we made an attempt to provide a reanalysis of indicators of forests productivity of Russia aiming at obtaining the results for which uncertainties could be estimated in a reliable and transparent way. Within a landscape-ecosystem approach it has required (1) development of an expert system for refinement of initial data including elimination of recognized biases; (2) delineation of ecological regions based on gradients of major indicators of productivity; (3) transition to multidimensional models (e.g., for calculation of spatially distributed biomass expansion factors); (4) use of process-based elements in empirical models; and (5) development of some approaches which presumably do not have recognized biases. However, taking into account the fuzzy character of the problem, the above approach (as well as any other individually used method) is

  18. 25 CFR 163.19 - Contracts for the sale of forest products.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 25 Indians 1 2011-04-01 2011-04-01 false Contracts for the sale of forest products. 163.19 Section 163.19 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER GENERAL FORESTRY REGULATIONS Forest Management and Operations § 163.19 Contracts for the sale of forest products. (a) In...

  19. 25 CFR 163.19 - Contracts for the sale of forest products.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 25 Indians 1 2013-04-01 2013-04-01 false Contracts for the sale of forest products. 163.19 Section 163.19 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER GENERAL FORESTRY REGULATIONS Forest Management and Operations § 163.19 Contracts for the sale of forest products. (a) In...

  20. 25 CFR 163.19 - Contracts for the sale of forest products.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 25 Indians 1 2014-04-01 2014-04-01 false Contracts for the sale of forest products. 163.19 Section 163.19 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER GENERAL FORESTRY REGULATIONS Forest Management and Operations § 163.19 Contracts for the sale of forest products. (a) In...

  1. 25 CFR 163.19 - Contracts for the sale of forest products.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 25 Indians 1 2012-04-01 2011-04-01 true Contracts for the sale of forest products. 163.19 Section 163.19 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER GENERAL FORESTRY REGULATIONS Forest Management and Operations § 163.19 Contracts for the sale of forest products. (a) In...

  2. 25 CFR 163.19 - Contracts for the sale of forest products.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false Contracts for the sale of forest products. 163.19 Section 163.19 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER GENERAL FORESTRY REGULATIONS Forest Management and Operations § 163.19 Contracts for the sale of forest products. (a) In...

  3. Outlook for U. S. forest resources for energy and wood products

    SciTech Connect

    Peterson, R.M.

    1984-01-01

    There will be increased demands placed on our forest resources in the future to generate energy an wood products. Recent legislation, such as the Resources Planning Act, will help to organize efforts to meet thes demands. Forest Service programs encourage intensive forest land management to produce more timber from our natural lands and greater utilization of our timber resources through more efficient production systems.

  4. Redox potential: An indicator of site productivity in forest management

    NASA Astrophysics Data System (ADS)

    Sajedi, Toktam; Prescott, Cindy; Lavkulich, Les

    2010-05-01

    Redox potential (Eh) is an integrated soil measurement that reflects several environmental conditions in the soil associated with aeration, moisture and carbon (organic matter) dynamics. Its measurement can be related to water table fluctuations, precipitation and landscape gradients, organic matter decomposition rates, nutrient dynamics, biological diversity and plant species distribution. Redox is an excellent indicator of soil biological processes, as it is largely a reflection of microbial activities which to a large extent govern carbon dynamics and nutrient cycling. Redox thus serves as an ecological indicator of site productivity at the ecosystem scale and may be used for management purposes as its magnitude can be altered by activities such as harvesting and drainage. A threshold value of 300 mv has been documented as the critical value below which anaerobic conditions in the soil develop. However, redox measurements and its impacts on ecosystem processes such as nutrient cycling and productivity, especially in forest ecosystems, have not received the attention that this "master" variable deserves, On northern Vancouver Island, Canada, regenerating stands of western redcedar-western hemlock (CH) sites exhibit symptoms of nutrient deficiencies and slow growth, but this phenomenon does not occur on adjacent western hemlock- amabalis fir (HA) sites. We tested the hypothesis that differences in nutrient supply and distribution of plant species was caused by differences in moisture regime and redox potential. Redox potential, pH, soil aeration depth (steel rods), organic matter thickness, bulk density, soil carbon store, plant species distribution and richness were measured at five old-growth and five 10-year-old cutover blocks. Results of investigations confirmed that CH forests were wetter, had redox values lower than the critical 300mv and a shallower aerated zone, compared with adjacent regenerating HA sites. Fifty percent of the CH plots had redox values

  5. Inter-annual Variability of Aboveground Net Primary Productivity in Regenerating Tropical Dry Forests

    NASA Astrophysics Data System (ADS)

    Powers, J. S.; Becknell, J. M.

    2015-12-01

    Globally, there are now more secondary forests regenerating following anthropogenic disturbance than primary forests. However, carbon dynamics in secondary tropical forests in general, and seasonally dry forests in particular, have not been as well studied as primary wet forests. Young, regenerating forests may be more sensitive to climatic variability than older forests because of their dynamic demographic rates. Similarly, seasonally dry tropical forests may be particularly sensitive to changes in precipitation, as tree growth is highly constrained by water availability. We examined how inter-annual variability in precipitation affected above-ground net primary productivity in chronosequences of dry forest in Costa Rica. Our sites included three forest cover types, whose distribution is linked to edaphic variation. Over our 6-yr dataset, annual rainfall varied from 1110 to 3040mm, with a 5-6 month dry season. ANPP ranged from 2.96 to 18.98 Mg ha-1 across sites that have been recovering for 7 to 67 years. Fine litter production dominated ANPP, and increased with forest age but not annual rainfall. By contrast, woody stem growth did not vary among forests that differed in age, but increased as a function of annual rainfall. These results differed by forest type. Lowland oak forests on low fertility soil had the lowest productivity and responses to rainfall, whereas forests on the highest fertility soils showed large increases in woody production with rainfall. Consistent with our expectation, younger forests on the intermediate soil type had higher variability in ANPP than older forests, but this was not significant for forests on the poor or high fertility soils. Our results highlight several important findings: 1) different components of ANPP vary in their responses to inter-annual variation in rainfall, 2) forest responses to climatic variability depend on species composition, which varies consistently with soil type in this landscape.

  6. 3 CFR 8442 - Proclamation 8442 of October 23, 2009. National Forest Products Week, 2009

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... States of America A Proclamation America’s forests have helped spur the growth and development that has... environment. This week, we recognize the value of forest products and the importance of their sustainable...

  7. 43 CFR 8224.1 - Use of the Fossil Forest Research Natural Area.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 43 Public Lands: Interior 2 2012-10-01 2012-10-01 false Use of the Fossil Forest Research Natural...) BUREAU OF LAND MANAGEMENT, DEPARTMENT OF THE INTERIOR RECREATION PROGRAMS PROCEDURES Fossil Forest Research Natural Area § 8224.1 Use of the Fossil Forest Research Natural Area. (a) Fossils may be...

  8. 43 CFR 8224.1 - Use of the Fossil Forest Research Natural Area.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 43 Public Lands: Interior 2 2011-10-01 2011-10-01 false Use of the Fossil Forest Research Natural...) BUREAU OF LAND MANAGEMENT, DEPARTMENT OF THE INTERIOR RECREATION PROGRAMS PROCEDURES Fossil Forest Research Natural Area § 8224.1 Use of the Fossil Forest Research Natural Area. (a) Fossils may be...

  9. 43 CFR 8224.1 - Use of the Fossil Forest Research Natural Area.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 43 Public Lands: Interior 2 2014-10-01 2014-10-01 false Use of the Fossil Forest Research Natural...) BUREAU OF LAND MANAGEMENT, DEPARTMENT OF THE INTERIOR RECREATION PROGRAMS PROCEDURES Fossil Forest Research Natural Area § 8224.1 Use of the Fossil Forest Research Natural Area. (a) Fossils may be...

  10. 43 CFR 8224.1 - Use of the Fossil Forest Research Natural Area.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 43 Public Lands: Interior 2 2013-10-01 2013-10-01 false Use of the Fossil Forest Research Natural...) BUREAU OF LAND MANAGEMENT, DEPARTMENT OF THE INTERIOR RECREATION PROGRAMS PROCEDURES Fossil Forest Research Natural Area § 8224.1 Use of the Fossil Forest Research Natural Area. (a) Fossils may be...

  11. Developing New Coastal Forest Restoration Products Based on Landsat, ASTER, and MODIS Data

    NASA Technical Reports Server (NTRS)

    Spruce, Joseph P.; Graham, William; Smoot, James

    2009-01-01

    This paper discusses an ongoing effort to develop new geospatial information products for aiding coastal forest restoration and conservation efforts in coastal Louisiana and Mississippi. This project employs Landsat, Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER), and Moderate Resolution Imaging Spectroradiometer (MODIS) satellite data in conjunction with airborne elevation data to compute coastal forest cover type maps and change detection products. Improved forest mapping products are needed to aid coastal forest restoration and management efforts of State and Federal agencies in the Northern Gulf of Mexico (NGOM) region. In particular, such products may aid coastal forest land acquisition and conservation easement procurements. This region's forests are often disturbed and subjected to multiple biotic and abiotic threats, including subsidence, salt water intrusion, hurricanes, sea-level rise, insect-induced defoliation and mortality, altered hydrology, wildfire, and conversion to non-forest land use. In some cases, such forest disturbance has led to forest loss or loss of regeneration capacity. In response, a case study was conducted to assess and demonstrate the potential of satellite remote sensing products for improving forest type maps and for assessing forest change over the last 25 years. Change detection products are needed for assessing risks for specific priority coastal forest types, such as live oak and baldcypress-dominated forest. Preliminary results indicate Landsat time series data are capable of generating the needed forest type and change detection products. Useful classifications were obtained using 2 strategies: 1) general forest classification based on use of 3 seasons of Landsat data from the same year; and 2) classification of specific forest types of concern using a single date of Landsat data in which a given targeted type is spectrally distinct compared to adjacent forested cover. When available, ASTER data was

  12. Research on machine learning framework based on random forest algorithm

    NASA Astrophysics Data System (ADS)

    Ren, Qiong; Cheng, Hui; Han, Hai

    2017-03-01

    With the continuous development of machine learning, industry and academia have released a lot of machine learning frameworks based on distributed computing platform, and have been widely used. However, the existing framework of machine learning is limited by the limitations of machine learning algorithm itself, such as the choice of parameters and the interference of noises, the high using threshold and so on. This paper introduces the research background of machine learning framework, and combined with the commonly used random forest algorithm in machine learning classification algorithm, puts forward the research objectives and content, proposes an improved adaptive random forest algorithm (referred to as ARF), and on the basis of ARF, designs and implements the machine learning framework.

  13. Rapid Increases in Forest Understory Diversity and Productivity following a Mountain Pine Beetle (Dendroctonus ponderosae) Outbreak in Pine Forests

    PubMed Central

    Pec, Gregory J.; Karst, Justine; Sywenky, Alexandra N.; Cigan, Paul W.; Erbilgin, Nadir; Simard, Suzanne W.; Cahill, James F.

    2015-01-01

    The current unprecedented outbreak of mountain pine beetle (Dendroctonus ponderosae) in lodgepole pine (Pinus contorta) forests of western Canada has resulted in a landscape consisting of a mosaic of forest stands at different stages of mortality. Within forest stands, understory communities are the reservoir of the majority of plant species diversity and influence the composition of future forests in response to disturbance. Although changes to stand composition following beetle outbreaks are well documented, information on immediate responses of forest understory plant communities is limited. The objective of this study was to examine the effects of D. ponderosae-induced tree mortality on initial changes in diversity and productivity of understory plant communities. We established a total of 110 1-m2 plots across eleven mature lodgepole pine forests to measure changes in understory diversity and productivity as a function of tree mortality and below ground resource availability across multiple years. Overall, understory community diversity and productivity increased across the gradient of increased tree mortality. Richness of herbaceous perennials increased with tree mortality as well as soil moisture and nutrient levels. In contrast, the diversity of woody perennials did not change across the gradient of tree mortality. Understory vegetation, namely herbaceous perennials, showed an immediate response to improved growing conditions caused by increases in tree mortality. How this increased pulse in understory richness and productivity affects future forest trajectories in a novel system is unknown. PMID:25859663

  14. Rapid Increases in forest understory diversity and productivity following a mountain pine beetle (Dendroctonus ponderosae) outbreak in pine forests.

    PubMed

    Pec, Gregory J; Karst, Justine; Sywenky, Alexandra N; Cigan, Paul W; Erbilgin, Nadir; Simard, Suzanne W; Cahill, James F

    2015-01-01

    The current unprecedented outbreak of mountain pine beetle (Dendroctonus ponderosae) in lodgepole pine (Pinus contorta) forests of western Canada has resulted in a landscape consisting of a mosaic of forest stands at different stages of mortality. Within forest stands, understory communities are the reservoir of the majority of plant species diversity and influence the composition of future forests in response to disturbance. Although changes to stand composition following beetle outbreaks are well documented, information on immediate responses of forest understory plant communities is limited. The objective of this study was to examine the effects of D. ponderosae-induced tree mortality on initial changes in diversity and productivity of understory plant communities. We established a total of 110 1-m2 plots across eleven mature lodgepole pine forests to measure changes in understory diversity and productivity as a function of tree mortality and below ground resource availability across multiple years. Overall, understory community diversity and productivity increased across the gradient of increased tree mortality. Richness of herbaceous perennials increased with tree mortality as well as soil moisture and nutrient levels. In contrast, the diversity of woody perennials did not change across the gradient of tree mortality. Understory vegetation, namely herbaceous perennials, showed an immediate response to improved growing conditions caused by increases in tree mortality. How this increased pulse in understory richness and productivity affects future forest trajectories in a novel system is unknown.

  15. Contribution of Near Real Time MODIS-Based Forest Disturbance Detection Products to a National Forest Threat Early Warning System

    NASA Technical Reports Server (NTRS)

    Spruce, Joseph P.; Hargrove, William; Glasser, Jerry; Kuper, Philip D.

    2011-01-01

    This presentation discusses an effort to compute and post weekly MODIS forest change products for the conterminous US (CONUS), as part of national forest threat early warning system (EWS) known as the U.S. Forest Change Assessment Viewer (FCAV). The US Forest Service, NASA, USGS, and ORNL are working collaboratively to contribute weekly change products to this EWS. Large acreages of the nation's forests are being disturbed by a growing multitude of biotic and abiotic threats that can act either singularly or in combination. When common at regional scales, such disturbances can pose hazards and threats to floral and faunal bio-diversity, ecosystem sustainability, ecosystem services, and human settlements across the conterminous US. Regionally evident forest disturbances range from ephemeral periodic canopy defoliation to stand replacement mortality events due to insects, disease, fire, hurricanes, tornadoes, ice, hail, and drought. Mandated by the Healthy Forest Restoration Act of 2003, this forest threat EWS has been actively developed since 2006 and on-line since 2010. This FCAV system employs 250-meter MODIS NDVI-based forest change products as a key element of the system, providing regional and CONUS scale products in near real time every 8 days. Each forest change product in FCAV is based on current versus historical 24 day composite NDVI data gridded at 231.66 meter resolution. Current NDVI is derived from USGS eMODIS expedited products. MOD13 NDVI is used for constructing historical baselines. CONUS change products are computed for all forests as % change in the current versus historical NDVI. Change products are computed according to previous year, previous 3 years and previous 8 year historical baselines. The use of multiple baselines enables disturbance anomaly phenology to be more fully assessed. CONUS forest change products are posted each week on the FCAV, a web mapping service maintained by the National Environmental Modeling and Analysis Center. The

  16. Cellulose factories: advancing bioenergy production from forest trees.

    PubMed

    Mizrachi, Eshchar; Mansfield, Shawn D; Myburg, Alexander A

    2012-04-01

    Fast-growing, short-rotation forest trees, such as Populus and Eucalyptus, produce large amounts of cellulose-rich biomass that could be utilized for bioenergy and biopolymer production. Major obstacles need to be overcome before the deployment of these genera as energy crops, including the effective removal of lignin and the subsequent liberation of carbohydrate constituents from wood cell walls. However, significant opportunities exist to both select for and engineer the structure and interaction of cell wall biopolymers, which could afford a means to improve processing and product development. The molecular underpinnings and regulation of cell wall carbohydrate biosynthesis are rapidly being elucidated, and are providing tools to strategically develop and guide the targeted modification required to adapt forest trees for the emerging bioeconomy. Much insight has already been gained from the perturbation of individual genes and pathways, but it is not known to what extent the natural variation in the sequence and expression of these same genes underlies the inherent variation in wood properties of field-grown trees. The integration of data from next-generation genomic technologies applied in natural and experimental populations will enable a systems genetics approach to study cell wall carbohydrate production in trees, and should advance the development of future woody bioenergy and biopolymer crops.

  17. Modeling annual production and carbon fluxes of a large managed temperate forest using forest inventories, satellite data and field measurements.

    PubMed

    Le Maire, Guerric; Davi, Hendrik; Soudani, Kamel; François, Christophe; Le Dantec, Valérie; Dufrêne, Eric

    2005-07-01

    We evaluated annual productivity and carbon fluxes over the Fontainebleau forest, a large heterogeneous forest region of 17,000 ha, in terms of species composition, canopy structure, stand age, soil type and water and mineral resources. The model is a physiological process-based forest ecosystem model coupled with an allocation model and a soil model. The simulations were done stand by stand, i.e., 2992 forest management units of simulation. Some input parameters that are spatially variable and to which the model is sensitive were calculated for each stand from forest inventory attributes, a network of 8800 soil pits, satellite data and field measurements. These parameters are: (1) vegetation attributes: species, age, height, maximal leaf area index of the year, aboveground biomass and foliar nitrogen content; and (2) soil attributes: available soil water capacity, soil depth and soil carbon content. Main outputs of the simulations are wood production and carbon fluxes on a daily to yearly basis. Results showed that the forest is a carbon sink, with a net ecosystem exchange of 371 g C m(-2) year(-1). Net primary productivity is estimated at 630 g C m(-2) year(-1) over the entire forest. Reasonably good agreement was found between simulated trunk relative growth rate (2.74%) and regional production estimated from the National Forest Inventory (IFN) (2.52%), as well as between simulated and measured annual wood production at the forest scale (about 71,000 and 68,000 m(3) year(-1), respectively). Results are discussed species by species.

  18. Chemical Characteristics of Two Forested Ultisols and Two Forested Inceptisols Relevant to Anion Production and Mobility

    SciTech Connect

    Johnson, D.W.

    2001-01-17

    As a prelude to a basic program on soil leaching, some chemical characteristics of two forested Ultisols in eastern Tennessee and two forested Inceptisols in western Washington are discussed in relation to the production and mobility of anions. These soils were chosen in an attempt to provide a range of free iron (Fe) and aluminum (Al) contents (which are hypothesized to be related to anion adsorption) and carbon:nitrogen (C:N) ratios (which are hypothesized to be related to nitrate and bicarbonate production) for field experiments involving C, N, and anion salt additions. The Washington Inceptisols had high free Fe and Al in surface horizons and decreasing free Fe and Al levels with depth, whereas the reverse was true of the Tennessee Ultisols. The alderwood-red alder and Tarklin (sinkhole) soils had higher N concentrations and lower C:N ratios in their surface horizons than the Alderwood-Douglas-fir and Fullerton soils, respectively, but the reverse was true of subsurface horizons. Patterns of and relationships among the above properties and pH, Bray phosphorus (No. 2); adsorbed and soluble SO{sub 4}{sup 2-}, Cl{sup -}, and NO{sub 3}{sup -}; cation exchange capacity; and exchangeable cations are discussed.

  19. Research publications of the pringle falls experimental forest, central Oregon cascade range, 1930 to 1993. Forest Service general technical report

    SciTech Connect

    Youngblood, A.

    1995-05-01

    An annotated bibliography of publications resulting from research at the Pringle Falls Experimental Forest, Deschutes National Forest, in central Oregon from 1930 to 1993 is presented. Over 100 publications are listed, including papers, theses, and reports. An index is provided that cross-references the listings under appropriate keywords.

  20. Consequences of increasing bioenergy demand on wood and forests: An application of the Global Forest Products Model

    USGS Publications Warehouse

    Buongiorno, J.; Raunikar, R.; Zhu, S.

    2011-01-01

    The Global Forest Products Model (GFPM) was applied to project the consequences for the global forest sector of doubling the rate of growth of bioenergy demand relative to a base scenario, other drivers being maintained constant. The results showed that this would lead to the convergence of the price of fuelwood and industrial roundwood, raising the price of industrial roundwood by nearly 30% in 2030. The price of sawnwood and panels would be 15% higher. The price of paper would be 3% higher. Concurrently, the demand for all manufactured wood products would be lower in all countries, but the production would rise in countries with competitive advantage. The global value added in wood processing industries would be 1% lower in 2030. The forest stock would be 2% lower for the world and 4% lower for Asia. These effects varied substantially by country. ?? 2011 Department of Forest Economics, SLU Ume??, Sweden.

  1. Tropical forest responses to increasing [CO2]: current knowledge and opportunities for future research

    SciTech Connect

    Cernusak, Lucas; Winter, Klaus; Dalling, James; Holtum, Joseph; Jaramillo, Carlos; Korner, Christian; Leakey, Andrew D.B.; Norby, Richard J; Poulter, Benjamin; Turner, Benjamin; Wright, S. Joseph

    2013-01-01

    Elevated atmospheric [CO2] (ca) will undoubtedly affect the metabolism of tropical forests worldwide; however, critical aspects of how tropical forests will respond remain largely unknown. Here we review the current state of knowledge about physiological and ecological responses, with the aim of providing a framework that can help to guide future experimental research. Modelling studies have indicated that elevated ca can potentially stimulate photosynthesis more in the tropics than at higher latitudes, because suppression of photorespiration by elevated ca increases with temperature. However, canopy leaves in tropical forests could also potentially reach a high temperature threshold under elevated ca that will moderate the rise in photosynthesis. Belowground responses, including fine root production, nutrient foraging, and soil organic matter processing, will be especially important to the integrated ecosystem response to elevated CO2. Water-use efficiency will increase as ca rises, potentially impacting upon soil moisture status and nutrient availability. Recruitment may be differentially altered for some functional groups, potentially decreasing ecosystem carbon storage. Whole-forest CO2 enrichment experiments are urgently needed to test predictions of tropical forest functioning under elevated ca. Smaller scale experiments in the understory and in gaps would also be informative, and could provide stepping stones toward stand-scale manipulations.

  2. Greenhouse gas mitigation on marginal land: a quantitative review of the relative benefits of forest recovery versus biofuel production.

    PubMed

    Evans, Samuel G; Ramage, Benjamin S; DiRocco, Tara L; Potts, Matthew D

    2015-02-17

    Decisions concerning future land-use/land cover change stand at the forefront of ongoing debates on how to best mitigate climate change. In this study, we compare the greenhouse gas (GHG) mitigation value over a 30-year time frame for a range of forest recovery and biofuel production scenarios on abandoned agricultural land. Carbon sequestration in recovering forests is estimated based on a statistical analysis of tropical and temperate studies on marginal land. GHGs offset by biofuel production are analyzed for five different production pathways. We find that forest recovery is superior to low-yielding biofuel production scenarios such as oil palm and corn. Biofuel production scenarios with high yields, such as sugarcane or high-yielding energy grasses, can be comparable or superior to natural forest succession and to reforestation in some cases. This result stands in contrast to previous research suggesting that restoring degraded ecosystems to their native state is generally superior to agricultural production in terms of GHG mitigation. Further work is needed on carbon stock changes in forests, soil carbon dynamics, and bioenergy crop production on degraded/abandoned agricultural land. This finding also emphasizes the need to consider the full range of social, economic, and ecological consequences of land-use policies.

  3. Medical Products Research

    NASA Technical Reports Server (NTRS)

    1982-01-01

    Ventrex Laboratories, Inc. develops, manufactures and markets a line of medical diagnostic assays based on biochemical techniques, in particular immunochemical techniques. Their products are sold worldwide to hospitals and medical laboratories for use in testing blood samples and other biological fluids. Analysis of a patient's body fluids, compared with normal values, aids a physician in confirming or otherwise diagnosing a suspected disease condition. NERAC's rapid information retrieval has provided Ventrex invaluable up-to-date information, and has permitted large scale savings. NERAC's service was particularly important in the development of a new product in the company's Ventre/Sep line, which is used in radioimmunoassays.

  4. Quantifying the missing link between forest albedo and productivity in the boreal zone

    NASA Astrophysics Data System (ADS)

    Hovi, Aarne; Liang, Jingjing; Korhonen, Lauri; Kobayashi, Hideki; Rautiainen, Miina

    2016-11-01

    Albedo and fraction of absorbed photosynthetically active radiation (FAPAR) determine the shortwave radiation balance and productivity of forests. Currently, the physical link between forest albedo and productivity is poorly understood, yet it is crucial for designing optimal forest management strategies for mitigating climate change. We investigated the relationships between boreal forest structure, albedo and FAPAR using a radiative transfer model called Forest Reflectance and Transmittance model FRT and extensive forest inventory data sets ranging from southern boreal forests to the northern tree line in Finland and Alaska (N = 1086 plots). The forests in the study areas vary widely in structure, species composition, and human interference, from intensively managed in Finland to natural growth in Alaska. We show that FAPAR of tree canopies (FAPARCAN) and albedo are tightly linked in boreal coniferous forests, but the relationship is weaker if the forest has broadleaved admixture, or if canopies have low leaf area and the composition of forest floor varies. Furthermore, the functional shape of the relationship between albedo and FAPARCAN depends on the angular distribution of incoming solar irradiance. We also show that forest floor can contribute to over 50 % of albedo or total ecosystem FAPAR. Based on our simulations, forest albedos can vary notably across the biome. Because of larger proportions of broadleaved trees, the studied plots in Alaska had higher albedo (0.141-0.184) than those in Finland (0.136-0.171) even though the albedo of pure coniferous forests was lower in Alaska. Our results reveal that variation in solar angle will need to be accounted for when evaluating climate effects of forest management in different latitudes. Furthermore, increasing the proportion of broadleaved trees in coniferous forests is the most important means of maximizing albedo without compromising productivity: based on our findings the potential of controlling forest

  5. Intertidal resource use over millennia enhances forest productivity

    NASA Astrophysics Data System (ADS)

    Trant, Andrew J.; Nijland, Wiebe; Hoffman, Kira M.; Mathews, Darcy L.; McLaren, Duncan; Nelson, Trisalyn A.; Starzomski, Brian M.

    2016-08-01

    Human occupation is usually associated with degraded landscapes but 13,000 years of repeated occupation by British Columbia's coastal First Nations has had the opposite effect, enhancing temperate rainforest productivity. This is particularly the case over the last 6,000 years when intensified intertidal shellfish usage resulted in the accumulation of substantial shell middens. We show that soils at habitation sites are higher in calcium and phosphorous. Both of these are limiting factors in coastal temperate rainforests. Western redcedar (Thuja plicata) trees growing on the middens were found to be taller, have higher wood calcium, greater radial growth and exhibit less top die-back. Coastal British Columbia is the first known example of long-term intertidal resource use enhancing forest productivity and we expect this pattern to occur at archaeological sites along coastlines globally.

  6. Intertidal resource use over millennia enhances forest productivity

    PubMed Central

    Trant, Andrew J.; Nijland, Wiebe; Hoffman, Kira M.; Mathews, Darcy L.; McLaren, Duncan; Nelson, Trisalyn A.; Starzomski, Brian M.

    2016-01-01

    Human occupation is usually associated with degraded landscapes but 13,000 years of repeated occupation by British Columbia's coastal First Nations has had the opposite effect, enhancing temperate rainforest productivity. This is particularly the case over the last 6,000 years when intensified intertidal shellfish usage resulted in the accumulation of substantial shell middens. We show that soils at habitation sites are higher in calcium and phosphorous. Both of these are limiting factors in coastal temperate rainforests. Western redcedar (Thuja plicata) trees growing on the middens were found to be taller, have higher wood calcium, greater radial growth and exhibit less top die-back. Coastal British Columbia is the first known example of long-term intertidal resource use enhancing forest productivity and we expect this pattern to occur at archaeological sites along coastlines globally. PMID:27572157

  7. Effects of climate change and shifts in forest composition on forest net primary production.

    PubMed

    Chiang, Jyh-Min; Iverson, Louts R; Prasad, Anantha; Brown, Kim J

    2008-11-01

    Forests are dynamic in both structure and species composition, and these dynamics are strongly influenced by climate. However, the net effects of future tree species composition on net primary production (NPP) are not well understood. The objective of this work was to model the potential range shifts of tree species (DISTRIB Model) and predict their impacts on NPP (PnET-II Model) that will be associated with alterations in species composition. We selected four 200 x 200 km areas in Wisconsin, Maine, Arkansas, and the Ohio-West Virginia area, representing focal areas of potential species range shifts. PnET-II model simulations were carried out assuming that all forests achieved steady state, of which the species compositions were predicted by DISTRIB model with no migration limitation. The total NPP under the current climate ranged from 552 to 908 g C/m(2) per year. The effects of potential species redistributions on NPP were moderate (-12% to +8%) compared with the influence of future climatic changes (-60% to +25%). The direction and magnitude of climate change effects on NPP were largely dependent on the degree of warming and water balance. Thus, the magnitude of future climate change can affect the feedback system between the atmosphere and biosphere.

  8. 36 CFR 223.219 - Sustainable harvest of special forest products.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... scale, and scientific data available prior to making their sustainability determination and establishing... on the sustainability of special forest products. Such monitoring may include, but is not limited...

  9. 36 CFR 223.219 - Sustainable harvest of special forest products.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... scale, and scientific data available prior to making their sustainability determination and establishing... on the sustainability of special forest products. Such monitoring may include, but is not limited...

  10. 36 CFR 223.219 - Sustainable harvest of special forest products.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... scale, and scientific data available prior to making their sustainability determination and establishing... on the sustainability of special forest products. Such monitoring may include, but is not limited...

  11. 36 CFR 223.219 - Sustainable harvest of special forest products.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... scale, and scientific data available prior to making their sustainability determination and establishing... on the sustainability of special forest products. Such monitoring may include, but is not limited...

  12. Coupled Physical/Chemical and Biofiltration Technologies to Reduce Air Emissions from Forest Products Industries

    SciTech Connect

    Gary D. McGinnis

    2001-12-31

    The research is a laboratory and bench-scale investigation of a system to concentrate and destroy volatile organic compounds (VOCs), including hazardous air pollutants, formed from the drying of wood and the manufacture of wood board products (e.g., particle board and oriented strandboard). The approach that was investigated involved concentrating the dilute VOCs (<500 ppmv) with a physical/chemical adsorption unit, followed by the treatment of the concentrated voc stream (2,000 to 2,500 ppmv) with a biofiltration unit. The research program lasted three years, and involved three research organizations. Michigan Technological University was the primary recipient of the financial assistance, the USDA Forest Products Laboratory (FPL) and Mississippi State University (MSU) were subcontractors to MTU. The ultimate objective of this research was to develop a pilot-scale demonstration of the technology with sufficient data to provide for the design of an industrial system. No commercialization activities were included in this project.

  13. Renewal of Collaborative Research: Economically Viable Forest Harvesting Practices That Increase Carbon Sequestration

    SciTech Connect

    Davidson, E.A.; Dail, D.B., Hollinger, D.; Scott, N.; Richardson, A.

    2012-08-02

    Forests provide wildlife habitat, water and air purification, climate moderation, and timber and nontimber products. Concern about climate change has put forests in the limelight as sinks of atmospheric carbon. The C stored in the global vegetation, mostly in forests, is nearly equivalent to the amount present in atmospheric CO{sub 2}. Both voluntary and government-mandated carbon trading markets are being developed and debated, some of which include C sequestration resulting from forest management as a possible tradeable commodity. However, uncertainties regarding sources of variation in sequestration rates, validation, and leakage remain significant challenges for devising strategies to include forest management in C markets. Hence, the need for scientifically-based information on C sequestration by forest management has never been greater. The consequences of forest management on the US carbon budget are large, because about two-thirds of the {approx}300 million hectare US forest resource is classified as 'commercial forest.' In most C accounting budgets, forest harvesting is usually considered to cause a net release of C from the terrestrial biosphere to the atmosphere. However, forest management practices could be designed to meet the multiple goals of providing wood and paper products, creating economic returns from natural resources, while sequestering C from the atmosphere. The shelterwood harvest strategy, which removes about 30% of the basal area of the overstory trees in each of three successive harvests spread out over thirty years as part of a stand rotation of 60-100 years, may improve net C sequestration compared to clear-cutting because: (1) the average C stored on the land surface over a rotation increases, (2) harvesting only overstory trees means that a larger fraction of the harvested logs can be used for long-lived sawtimber products, compared to more pulp resulting from clearcutting, (3) the shelterwood cut encourages growth of subcanopy trees

  14. Forest Productivity and Diversity: Using Ecological Theory and Landscape Models to Guide Sustainable Forest Management

    SciTech Connect

    Huston, M.A.

    1998-11-01

    Sustainable forest management requires maintaining or increasing ecosystem productivity, while preserving or restoring natural levels of biodiversity. Application of general concepts from ecological theory, along with use of mechanistic, landscape-based computer models, can contribute to the successful achievement of both of these objectives. Ecological theories based on the energetics and dynamics of populations can be used to predict the general distribution of individual species, the diversity of different types of species, ecosystem process rates and pool sizes, and patterns of spatial and temporal heterogeneity over a broad range of environmental conditions. This approach requires subdivision of total biodiversity into functional types of organisms, primarily because different types of organisms respond very differently to the spatial and temporal variation of environmental conditions on landscapes. The diversity of species of the same functional type (particularly among plants) tends to be highest at relatively low levels of net primary productivity, while the total number of different functional types (particularly among animals) tends to be highest at high levels of productivity (e.g., site index or potential net primary productivity). In general, the diversity of animals at higher trophic levels (e.g., predators) reaches its maximum at much higher levels of productivity than the diversity of lower trophic levels (e.g., plants). This means that a single environment cannot support high diversity of all types of organisms. Within the framework of the general patterns described above, the distributions, population dynamics, and diversity of organisms in specific regions can be predicted more precisely using a combination of computer simulation models and GIS data based on satellite information and ground surveys. Biophysical models that use information on soil properties, climate, and hydrology have been developed to predict how the abundance and spatial

  15. Multiple successional pathways in human-modified tropical landscapes: new insights from forest succession, forest fragmentation and landscape ecology research.

    PubMed

    Arroyo-Rodríguez, Víctor; Melo, Felipe P L; Martínez-Ramos, Miguel; Bongers, Frans; Chazdon, Robin L; Meave, Jorge A; Norden, Natalia; Santos, Bráulio A; Leal, Inara R; Tabarelli, Marcelo

    2017-02-01

    Old-growth tropical forests are being extensively deforested and fragmented worldwide. Yet forest recovery through succession has led to an expansion of secondary forests in human-modified tropical landscapes (HMTLs). Secondary forests thus emerge as a potential repository for tropical biodiversity, and also as a source of essential ecosystem functions and services in HMTLs. Such critical roles are controversial, however, as they depend on successional, landscape and socio-economic dynamics, which can vary widely within and across landscapes and regions. Understanding the main drivers of successional pathways of disturbed tropical forests is critically needed for improving management, conservation, and restoration strategies. Here, we combine emerging knowledge from tropical forest succession, forest fragmentation and landscape ecology research to identify the main driving forces shaping successional pathways at different spatial scales. We also explore causal connections between land-use dynamics and the level of predictability of successional pathways, and examine potential implications of such connections to determine the importance of secondary forests for biodiversity conservation in HMTLs. We show that secondary succession (SS) in tropical landscapes is a multifactorial phenomenon affected by a myriad of forces operating at multiple spatio-temporal scales. SS is relatively fast and more predictable in recently modified landscapes and where well-preserved biodiversity-rich native forests are still present in the landscape. Yet the increasing variation in landscape spatial configuration and matrix heterogeneity in landscapes with intermediate levels of disturbance increases the uncertainty of successional pathways. In landscapes that have suffered extensive and intensive human disturbances, however, succession can be slow or arrested, with impoverished assemblages and reduced potential to deliver ecosystem functions and services. We conclude that: (i

  16. Bioenergy production and forest landscape change in the southeastern United States

    USGS Publications Warehouse

    Costanza, Jennifer K.; Abt, Robert C.; McKerrow, Alexa; Collazo, Jaime

    2016-01-01

    Production of woody biomass for bioenergy, whether wood pellets or liquid biofuels, has the potential to cause substantial landscape change and concomitant effects on forest ecosystems, but the landscape effects of alternative production scenarios have not been fully assessed. We simulated landscape change from 2010 to 2050 under five scenarios of woody biomass production for wood pellets and liquid biofuels in North Carolina, in the southeastern United States, a region that is a substantial producer of wood biomass for bioenergy and contains high biodiversity. Modeled scenarios varied biomass feedstocks, incorporating harvest of ‘conventional’ forests, which include naturally regenerating as well as planted forests that exist on the landscape even without bioenergy production, as well as purpose-grown woody crops grown on marginal lands. Results reveal trade-offs among scenarios in terms of overall forest area and the characteristics of the remaining forest in 2050. Meeting demand for biomass from conventional forests resulted in more total forest land compared with a baseline, business-as-usual scenario. However, the remaining forest was composed of more intensively managed forest and less of the bottomland hardwood and longleaf pine habitats that support biodiversity. Converting marginal forest to purpose-grown crops reduced forest area, but the remaining forest contained more of the critical habitats for biodiversity. Conversion of marginal agricultural lands to purpose-grown crops resulted in smaller differences from the baseline scenario in terms of forest area and the characteristics of remaining forest habitats. Each scenario affected the dominant type of land-use change in some regions, especially in the coastal plain that harbors high levels of biodiversity. Our results demonstrate the complex landscape effects of alternative bioenergy scenarios, highlight that the regions most likely to be affected by bioenergy production are also critical for

  17. Litterfall production along successional and altitudinal gradients of subtropical monsoon evergreen broadleaved forests in Guangdong, China

    USGS Publications Warehouse

    Zhou, G.; Guan, L.; Wei, X.; Zhang, Dongxiao; Zhang, Q.; Yan, J.; Wen, D.; Liu, J.; Liu, S.; Huang, Z.; Kong, G.; Mo, J.; Yu, Q.

    2007-01-01

    Evaluation of litterfall production is important for understanding nutrient cycling, forest growth, successional pathways, and interactions with environmental variables in forest ecosystems. Litterfall was intensively studied during the period of 1982-2001 in two subtropical monsoon vegetation gradients in the Dinghushan Biosphere Reserve, Guangdong Province, China. The two gradients include: (1) a successional gradient composed of pine forest (PF), mixed pine and broadleaved forest (MF) and monsoon evergreen broadleaved forest (BF), and (2) an altitudinal gradient composed of Baiyunci ravine rain forest (BRF), Qingyunci ravine rain forest (QRF), BF and mountainous evergreen broadleaved forest (MMF). Mean annual litterfall production was 356, 861 and 849 g m-2 for PF, MF and BF of the successional gradient, and 1016, 1061, 849 and 489 g m-2 for BRF, QRF, BF and MMF of the altitudinal gradient, respectively. As expected, mean annual litterfall of the pioneer forest PF was the lowest, but rapidly increased over the observation period while those in other forests were relatively stable, confirming that forest litterfall production is closely related to successional stages and growth patterns. Leaf proportions of total litterfall in PF, MF, BF, BRF, QRF and MMF were 76.4%, 68.4%, 56.8%, 55.7%, 57.6% and 69.2%, respectively, which were consistent with the results from studies in other evergreen broadleaved forests. Our analysis on litterfall monthly distributions indicated that litterfall production was much higher during the period of April to September compared to other months for all studied forest types. Although there were significant impacts of some climate variables (maximum and effective temperatures) on litterfall production in some of the studied forests, the mechanisms of how climate factors (temperature and rainfall) interactively affect litterfall await further study. ?? 2006 Springer Science+Business Media B.V.

  18. Impacts of insect-related forest mortality on hydrologic partitioning and forest productivity in the Southern Rocky Mountains, USA

    NASA Astrophysics Data System (ADS)

    Molotch, N. P.

    2014-12-01

    Recent large-scale changes in forest cover over Western North America associated with insect-related forest mortality may have widespread impacts on water availability. These changes have potentially varied impacts on water availability as forest mortality influences rates of snow accumulation, snowmelt, and evapotranspiration. These changes may significantly alter runoff production and gross primary productivity in mountain forests. Analysis of remotely sensed vegetation greenness data indicate strong forest and understory growth dependencies associated with snow accumulation and snowmelt with peak snow water equivalent explaining 40-50% of inter-annual greenness variability in the Rocky Mountains. Examples of these dependencies will be presented based on the 2012 drought in the Southwestern US whereby near record low snow accumulation and record high potential evapotranspiration have resulted in record low forest greening as evident in the 30+ year satellite record. Forest response to aridity in 2012 was exacerbated by forest disturbance with greenness anomalies 90% greater in magnitude in Bark Beetle and Spruce Budworm affected areas versus undisturbed areas and 182% greater in magnitude in areas impacted by fire. Growing season length was inversely proportional to peak greenness with record high Normalized Difference Vegetation Index (NDVI) values in April (14% above average) corresponding with record low NDVI values in July (7% below average). Gross primary productivity (GPP) estimates from the Moderate Resolution Imaging Spectroradiometer (MODIS) and from the Niwot Ridge, Colorado Ameriflux tower indicate record high April GPP (30% and 90% above average for MODIS and the tower, respectively) correspodning with record low July GPP (19% and 30% below average, respectively). Differences in these energy, water, ecosystem relationships among difference distrurbance regimes indicate that the sensitivity of ecosystems to changes in climate is heavily dependent on

  19. Forest management under changing climate conditions: Is timing a tool for Sustainable Forest Management? Relevant questions for research development

    NASA Astrophysics Data System (ADS)

    D'Aprile, Fabrizio; McShane, Paul; Tapper, Nigel

    2013-04-01

    Change of climate conditions influence energy fluxes applicable to forest ecosystems. These affect cycles of nutrients and materials, primary productivity of the ecosystem, biodiversity, ecological functionality and, consequently, carbon equilibria of the forest ecosystem. Temporal factors influence physical, biological, ecological, and climatic processes and functions. For example, seasonality, cycles, periodicity, and trends in climate variables; tree growth, forest growth, and forest metabolic activities (i.e., photosynthesis and respiration) are commonly known to be time-related. In tropical forests, the impacts of changing climate conditions may exceed temperature and/or precipitation thresholds critical to forest tree growth or health. Historically, forest management emphasises growth rates and financial returns as affected by species and site. Until recently, the influence of climate variability on growth dynamics has not been influential in forest planning and management. Under this system, especially in climatic and forest regions where most of species are stenoecious, periodical wood harvesting may occur in any phase of growth (increasing, decreasing, peak, and trough). This scenario presents four main situations: a) harvesting occurs when the rate of growth is decreasing: future productivity is damaged; the minimum biomass capital may be altered, and CO2 storage is negatively affected; b) harvesting occurs during a trough of the rate of growth: the minimum biomass capital necessary to preserve the resilience of the forest is damaged; the damage can be temporary (decades) or permanent; CO2 storage capacity is deficient - which may be read as an indirect emission of CO2 since the balance appears negative; c) harvesting occurs when the rate of growth is increasing: the planned wood mass can be used without compromising the resilience and recovery of the forest; CO2 storage remains increasing; d) harvesting occurs during a peak period of growth: the wood

  20. Environmental and economic suitability of forest biomass-based bioenergy production in the Southern United States

    NASA Astrophysics Data System (ADS)

    Dwivedi, Puneet

    This study attempts to ascertain the environmental and economic suitability of utilizing forest biomass for cellulosic ethanol production in the Southern United States. The study is divided into six chapters. The first chapter details the background and defines the relevance of the study along with objectives. The second chapter reviews the existing literature to ascertain the present status of various existing conversion technologies. The third chapter assesses the net energy ratio and global warming impact of ethanol produced from slash pine (Pinus elliottii Engelm.) biomass. A life-cycle assessment was applied to achieve the task. The fourth chapter assesses the role of emerging bioenergy and voluntary carbon markets on the profitability of non-industrial private forest (NIPF) landowners by combining the Faustmann and Hartmann models. The fifth chapter assesses perceptions of four stakeholder groups (Non-Government Organization, Academics, Industries, and Government) on the use of forest biomass for bioenergy production in the Southern United States using the SWOT-AHP (Strength, Weakness, Opportunity, and Threat-Analytical Hierarchy Process) technique. Finally, overall conclusions are made in the sixth chapter. Results indicate that currently the production of cellulosic ethanol is limited as the production cost of cellulosic ethanol is higher than the production cost of ethanol derived from corn. However, it is expected that the production cost of cellulosic ethanol will come down in the future from its current level due to ongoing research efforts. The total global warming impact of E85 fuel (production and consumption) was found as 10.44 tons where as global warming impact of an equivalent amount of gasoline (production and consumption) was 21.45 tons. This suggests that the production and use of ethanol derived from slash pine biomass in the form of E85 fuel in an automobile saves about 51% of carbon emissions when compared to gasoline. The net energy ratio

  1. Long-term elevated atmospheric CO2 enhances forest productivity

    NASA Astrophysics Data System (ADS)

    Loecke, T. D.; Groffman, P. M.; Treseder, K. K.; LaDeau, S.

    2011-12-01

    that warmer sites also promote tree growth. In- growth root cores, soil N mineralization and nitrification assays, and soil C and N contents all suggest that N is unlikely to be limiting current tree productivity on most sites across our rural to urban transect. Furthermore, soil lead content varied little across these forest sites, suggesting that heavy metal contamination is not likely a significant control on forest productivity in our study. These results lend support for the overarching hypothesis that terrestrial ecosystems will sequester more C under greater atmospheric CO2 concentrations and warmer air temperatures.

  2. Use of Multi-Year MODIS Phenological Data Products to Detect and Monitor Forest Disturbances at Regional and National Scales

    NASA Technical Reports Server (NTRS)

    Spruce, Joseph; Hargrove, William W.; Gasser, Jerry; Smoot, James; Ross, Kenton

    2010-01-01

    This presentation discusses an effort to use select MODIS phenological products for forest disturbance monitoring at the regional and CONUS scales. Forests occur on 1/3 of the U.S. land base and include regionally prevalent forest disturbances that can threaten forest sustainability. Regional and CONUS forest disturbance monitoring is needed for a national forest threat early warning system being developed by the USDA Forest Service with help from NASA, ORNL, and USGS. MODIS NDVI phenology products are being used to develop forest disturbance monitoring capabilities of this EWS.

  3. Net primary production of forests: a constant fraction of gross primary production?

    PubMed

    Waring, R. H.; Landsberg, J. J.; Williams, M.

    1998-02-01

    Considerable progress has been made in our ability to model and measure annual gross primary production (GPP) by terrestrial vegetation. But challenges remain in estimating maintenance respiration (R(m)) and net primary production (NPP). To search for possible common relationships, we assembled annual carbon budgets from six evergreen and one deciduous forest in Oregon, USA, three pine plantations in New South Wales, Australia, a deciduous forest in Massachusetts, USA, and a Nothofagus forest on the South Island of New Zealand. At all 12 sites, a standard procedure was followed to estimate annual NPP of foliage, branches, stems, and roots, the carbon expended in synthesis of these organs (R(g)), their R(m), and that of previously produced foliage and sapwood in boles, branches, and large roots. In the survey, total NPP ranged from 120 to 1660 g C m(-2) year(-1), whereas the calculated fraction allocated to roots varied from 0.22 to 0.63. Comparative analysis indicated that the total NPP/GPP ratio was conservative (0.47 +/- 0.04 SD). This finding supports the possibility of greatly simplifying forest growth models. The constancy of the NPP/GPP ratio also provides an incentive to renew efforts to understand the environmental factors affecting partitioning of NPP above and belowground.

  4. Effects of productivity on biodiversity in forest ecosystems across the United States and China.

    PubMed

    Liang, Jingjing; Watson, James V; Zhou, Mo; Lei, Xiangdong

    2016-04-01

    In the global campaign against biodiversity loss in forest ecosystems, land managers need to know the status of forest biodiversity, but practical guidelines for conserving biodiversity in forest management are lacking. A major obstacle is the incomplete understanding of the relationship between site primary productivity and plant diversity, due to insufficient ecosystem-wide data, especially for taxonomically and structurally diverse forest ecosystems. We investigated the effects of site productivity (the site's inherent capacity to grow timber) on tree species richness across 19 types of forest ecosystems in North America and China through 3 ground-sourced forest inventory data sets (U.S. Forest Inventory and Analysis, Cooperative Alaska Forest Inventory, and Chinese Forest Management Planning Inventory). All forest types conformed to a consistent and highly significant (P < 0.001) hump-shaped unimodal relationship, of which the generalized coefficients of determination averaged 20.5% over all the forest types. That is, tree species richness first increased as productivity increased at a progressively slower rate, and, after reaching a maximum, richness started to decline. Our consistent findings suggest that forests of high productivity would sustain few species because they consist mostly of flat homogeneous areas lacking an environmental gradient along which a diversity of species with different habitats can coexist. The consistency of the productivity-biodiversity relationship among the 3 data sets we examined makes it possible to quantify the expected tree species richness that a forest stand is capable of sustaining, and a comparison between the actual species richness and the sustainable values can be useful in prioritizing conservation efforts.

  5. 3 CFR 8738 - Proclamation 8738 of October 14, 2011. National Forest Products Week, 2011

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... green building materials, forests also provide a wide variety of products that make up an important part... commitment to the responsible management and conservation of forests around the world, we sow the seeds of a greener future for our children and grandchildren. To recognize the importance of products from...

  6. 3 CFR 8587 - Proclamation 8587 of October 15, 2010. National Forest Products Week, 2010

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... their products have played a vital role in our growth and economic development. Forests have also... Products Week, we recognize the enduring value of forests as sustainable, renewable, and bountiful... medicinal plants; and examined more sustainable green building practices. Through careful conservation...

  7. Rate of woody residue incorporation into Northern Rocky Mountain forest soils. Forest service research paper

    SciTech Connect

    Harvey, A.E.; Larsen, M.J.; Jurgensen, M.F.

    1981-08-01

    The important properties contributed to forest soils by decayed wood in the Northern Rocky Mountains make it desirable to determine the time required to reconstitute such materials in depleted soils. The ratio of fiber production potential (growth) to total quantity of wood in a steady state ecosystem provides estimates varying from approximately 100 to 300 years, depending on habitat type, for replacement of decayed soil wood. Radiocarbon dating of decayed wood in various stages of incorporation into the soil ranged from 100 to 550 years, depending on site and depth in soil. Species identification of decayed wood indicated that Douglas-fir residue is the most persistent woody material in these Northern Rocky Mountain soils.

  8. A Bayesian Belief Network approach to assess the potential of non wood forest products for small scale forest owners

    NASA Astrophysics Data System (ADS)

    Vacik, Harald; Huber, Patrick; Hujala, Teppo; Kurtilla, Mikko; Wolfslehner, Bernhard

    2015-04-01

    It is an integral element of the European understanding of sustainable forest management to foster the design and marketing of forest products, non-wood forest products (NWFPs) and services that go beyond the production of timber. Despite the relevance of NWFPs in Europe, forest management and planning methods have been traditionally tailored towards wood and wood products, because most forest management models and silviculture techniques were developed to ensure a sustained production of timber. Although several approaches exist which explicitly consider NWFPs as management objectives in forest planning, specific models are needed for the assessment of their production potential in different environmental contexts and for different management regimes. Empirical data supporting a comprehensive assessment of the potential of NWFPs are rare, thus making development of statistical models particularly problematic. However, the complex causal relationships between the sustained production of NWFPs, the available ecological resources, as well as the organizational and the market potential of forest management regimes are well suited for knowledge-based expert models. Bayesian belief networks (BBNs) are a kind of probabilistic graphical model that have become very popular to practitioners and scientists mainly due to the powerful probability theory involved, which makes BBNs suitable to deal with a wide range of environmental problems. In this contribution we present the development of a Bayesian belief network to assess the potential of NWFPs for small scale forest owners. A three stage iterative process with stakeholder and expert participation was used to develop the Bayesian Network within the frame of the StarTree Project. The group of participants varied in the stages of the modelling process. A core team, consisting of one technical expert and two domain experts was responsible for the entire modelling process as well as for the first prototype of the network

  9. Interpreting forest and grassland biome productivity utilizing nested scales of image resolution and biogeographical analysis

    NASA Technical Reports Server (NTRS)

    Iverson, L. R.; Cook, E. A.; Graham, R. L.; Olson, J. S.; Frank, T.; Ke, Y.; Treworgy, C.; Risser, P. G.

    1986-01-01

    Several hardware, software, and data collection problems encountered were conquered. The Geographic Information System (GIS) data from other systems were converted to ERDAS format for incorporation with the image data. Statistical analysis of the relationship between spectral values and productivity is being pursued. Several project sites, including Jackson, Pope, Boulder, Smokies, and Huntington Forest are evolving as the most intensively studied areas, primarily due to availability of data and time. Progress with data acquisition and quality checking, more details on experimental sites, and brief summarizations of research results and future plans are discussed. Material on personnel, collaborators, facilities, site background, and meetings and publications of the investigators are included.

  10. Linking state-and-transition simulation and timber supply models for forest biomass production scenarios

    USGS Publications Warehouse

    Costanza, Jennifer; Abt, Robert C.; McKerrow, Alexa; Collazo, Jaime

    2015-01-01

    We linked state-and-transition simulation models (STSMs) with an economics-based timber supply model to examine landscape dynamics in North Carolina through 2050 for three scenarios of forest biomass production. Forest biomass could be an important source of renewable energy in the future, but there is currently much uncertainty about how biomass production would impact landscapes. In the southeastern US, if forests become important sources of biomass for bioenergy, we expect increased land-use change and forest management. STSMs are ideal for simulating these landscape changes, but the amounts of change will depend on drivers such as timber prices and demand for forest land, which are best captured with forest economic models. We first developed state-and-transition model pathways in the ST-Sim software platform for 49 vegetation and land-use types that incorporated each expected type of landscape change. Next, for the three biomass production scenarios, the SubRegional Timber Supply Model (SRTS) was used to determine the annual areas of thinning and harvest in five broad forest types, as well as annual areas converted among those forest types, agricultural, and urban lands. The SRTS output was used to define area targets for STSMs in ST-Sim under two scenarios of biomass production and one baseline, business-as-usual scenario. We show that ST-Sim output matched SRTS targets in most cases. Landscape dynamics results indicate that, compared with the baseline scenario, forest biomass production leads to more forest and, specifically, more intensively managed forest on the landscape by 2050. Thus, the STSMs, informed by forest economics models, provide important information about potential landscape effects of bioenergy production.

  11. Improving Post-Hurricane Katrina Forest Management with MODIS Time Series Products

    NASA Technical Reports Server (NTRS)

    Lewis, Mark David; Spruce, Joseph; Evans, David; Anderson, Daniel

    2012-01-01

    Hurricane damage to forests can be severe, causing millions of dollars of timber damage and loss. To help mitigate loss, state agencies require information on location, intensity, and extent of damaged forests. NASA's MODerate Resolution Imaging Spectroradiometer (MODIS) Normalized Difference Vegetation Index (NDVI) time series data products offers a potential means for state agencies to monitor hurricane-induced forest damage and recovery across a broad region. In response, a project was conducted to produce and assess 250 meter forest disturbance and recovery maps for areas in southern Mississippi impacted by Hurricane Katrina. The products and capabilities from the project were compiled to aid work of the Mississippi Institute for Forest Inventory (MIFI). A series of NDVI change detection products were computed to assess hurricane induced damage and recovery. Hurricane-induced forest damage maps were derived by computing percent change between MODIS MOD13 16-day composited NDVI pre-hurricane "baseline" products (2003 and 2004) and post-hurricane NDVI products (2005). Recovery products were then computed in which post storm 2006, 2007, 2008 and 2009 NDVI data was each singularly compared to the historical baseline NDVI. All percent NDVI change considered the 16-day composite period of August 29 to September 13 for each year in the study. This provided percent change in the maximum NDVI for the 2 week period just after the hurricane event and for each subsequent anniversary through 2009, resulting in forest disturbance products for 2005 and recovery products for the following 4 years. These disturbance and recovery products were produced for the Mississippi Institute for Forest Inventory's (MIFI) Southeast Inventory District and also for the entire hurricane impact zone. MIFI forest inventory products were used as ground truth information for the project. Each NDVI percent change product was classified into 6 categories of forest disturbance intensity. Stand age

  12. Fires increase Amazon forest productivity through increases in diffuse radiation

    NASA Astrophysics Data System (ADS)

    Rap, A.; Spracklen, D. V.; Mercado, L.; Reddington, C. L.; Haywood, J. M.; Ellis, R. J.; Phillips, O. L.; Artaxo, P.; Bonal, D.; Restrepo Coupe, N.; Butt, N.

    2015-06-01

    Atmospheric aerosol scatters solar radiation increasing the fraction of diffuse radiation and the efficiency of photosynthesis. We quantify the impacts of biomass burning aerosol (BBA) on diffuse radiation and plant photosynthesis across Amazonia during 1998-2007. Evaluation against observed aerosol optical depth allows us to provide lower and upper BBA emissions estimates. BBA increases Amazon basin annual mean diffuse radiation by 3.4-6.8% and net primary production (NPP) by 1.4-2.8%, with quoted ranges driven by uncertainty in BBA emissions. The enhancement of Amazon basin NPP by 78-156 Tg C a-1 is equivalent to 33-65% of the annual regional carbon emissions from biomass burning. This NPP increase occurs during the dry season and acts to counteract some of the observed effect of drought on tropical production. We estimate that 30-60 Tg C a-1 of this NPP enhancement is within woody tissue, accounting for 8-16% of the observed carbon sink across mature Amazonian forests.

  13. Production and retention of methylmercury in inundated boreal forest soils.

    PubMed

    Rolfhus, Kristofer R; Hurley, James P; Bodaly, Richard A Drew; Perrine, Gregory

    2015-03-17

    The Flooded Uplands Dynamics Experiment (FLUDEX) was an ecosystem-scale study examining the production of methylmercury (MeHg) and greenhouse gases from reservoirs constructed on an upland boreal forest landscape in order to quantify their dependence upon carbon stores. We detail the within-reservoir production and storage of MeHg before, during, and nine years after the experiment. The reservoirs were net MeHg producers during the first two years of flooding, and net demethylating systems afterward. During years 1-3, a rapid pulse of MeHg and total Hg was observed in floodwater, followed by substantial increases in MeHg in seston and sediment. Resampling of the dry reservoirs nine years after the experiment ended indicated that organic soil MeHg was still 8 to 52-fold higher than preflood conditions, and averaged 86% of the levels recorded at the end of the third flooding year. Both total Hg and MeHg retention in soil were a strong function of organic carbon content. The time scale of soil MeHg retention may help explain the decadal time lag frequently observed for the decrease of piscivorous fish Hg concentrations in new reservoirs. Predicted extreme precipitation events associated with climate change may serve to make landscapes more susceptible to this process.

  14. Short and long-term carbon balance of bioenergy electricity production fueled by forest treatments

    PubMed Central

    Barnes, Kallie L; Ryan, Michael G; Neff, Jason C

    2014-01-01

    Background Forests store large amounts of carbon in forest biomass, and this carbon can be released to the atmosphere following forest disturbance or management. In the western US, forest fuel reduction treatments designed to reduce the risk of high severity wildfire can change forest carbon balance by removing carbon in the form of biomass, and by altering future potential wildfire behavior in the treated stand. Forest treatment carbon balance is further affected by the fate of this biomass removed from the forest, and the occurrence and intensity of a future wildfire in this stand. In this study we investigate the carbon balance of a forest treatment with varying fates of harvested biomass, including use for bioenergy electricity production, and under varying scenarios of future disturbance and regeneration. Results Bioenergy is a carbon intensive energy source; in our study we find that carbon emissions from bioenergy electricity production are nearly twice that of coal for the same amount of electricity. However, some emissions from bioenergy electricity production are offset by avoided fossil fuel electricity emissions. The carbon benefit achieved by using harvested biomass for bioenergy electricity production may be increased through avoided pyrogenic emissions if the forest treatment can effectively reduce severity. Conclusion Forest treatments with the use of harvested biomass for electricity generation can reduce carbon emissions to the atmosphere by offsetting fossil fuel electricity generation emissions, and potentially by avoided pyrogenic emissions due to reduced intensity and severity of a future wildfire in the treated stand. However, changes in future wildfire and regeneration regimes may affect forest carbon balance and these climate-induced changes may influence forest carbon balance as much, or more, than bioenergy production. PMID:25187788

  15. Soil and vegetation response to soil compaction and forest floor removal after aspen harvesting. Forest Service research paper

    SciTech Connect

    Alban, D.H.; Host, G.E.; Elioff, J.D.; Shadis, D.

    1994-01-01

    Reduced soil porosity and organic matter removal have been identified as common factors associated with loss of forest productivity (Powers et al. 1990). In both agriculture and forestry, management activities can modify soil porosity and organic matter with resultant impacts on vegetative growth. As part of a nationwide long-term soil productivity (LTSP) study soil porosity and organic matter are being experimentally manipulated on large plots to determine the impacts of such manipulations on growth and species diversity for a wide range of forest types.

  16. Evaluating Spatial-Temporal Dynamics of Net Primary Productivity of Different Forest Types in Northeastern China Based on Improved FORCCHN

    PubMed Central

    Zhao, Junfang; Yan, Xiaodong; Guo, Jianping; Jia, Gensuo

    2012-01-01

    An improved individual-based forest ecosystem carbon budget model for China (FORCCHN) was applied to investigate the spatial-temporal dynamics of net primary productivity of different forest types in northeastern China. In this study, the forests of northeastern China were categorized into four ecological types according to their habitats and generic characteristics (evergreen broadleaf forest, deciduous broadleaf forest, evergreen needleleaf forest and deciduous needleleaf forest). The results showed that distribution and change of forest NPP in northeastern China were related to the different forest types. From 1981 to 2002, among the forest types in northeastern China, per unit area NPP and total NPP of deciduous broadleaf forest were the highest, with the values of 729.4 gC/(m2•yr) and 106.0 TgC/yr, respectively, followed by mixed broadleaf- needleleaf forest, deciduous needleleaf forest and evergreen needleleaf forest. From 1981 to 2002, per unit area NPP and total NPP of different forest types in northeastern China exhibited significant trends of interannual increase, and rapid increase was found between the 1980s and 1990s. The contribution of the different forest type’s NPP to total NPP in northeastern China was clearly different. The greatest was deciduous broadleaf forest, followed by mixed broadleaf- needleleaf forest and deciduous needleleaf forest. The smallest was evergreen needleleaf forest. Spatial difference in NPP between different forest types was remarkable. High NPP values of deciduous needleleaf forest, mixed broadleaf- needleleaf forest and deciduous broadleaf forest were found in the Daxing’anling region, the southeastern of Xiaoxing’anling and Jilin province, and the Changbai Mountain, respectively. However, no regional differences were found for evergreen needleleaf NPP. This study provided not only an estimation NPP of different forest types in northeastern China but also a useful methodology for estimating forest carbon storage

  17. The impact of charcoal production on forest degradation: a case study in Tete, Mozambique

    NASA Astrophysics Data System (ADS)

    Sedano, F.; Silva, J. A.; Machoco, R.; Meque, C. H.; Sitoe, A.; Ribeiro, N.; Anderson, K.; Ombe, Z. A.; Baule, S. H.; Tucker, C. J.

    2016-09-01

    Charcoal production for urban energy consumption is a main driver of forest degradation in sub Saharan Africa. Urban growth projections for the continent suggest that the relevance of this process will increase in the coming decades. Forest degradation associated to charcoal production is difficult to monitor and commonly overlooked and underrepresented in forest cover change and carbon emission estimates. We use a multitemporal dataset of very high-resolution remote sensing images to map kiln locations in a representative study area of tropical woodlands in central Mozambique. The resulting maps provided a characterization of the spatial extent and temporal dynamics of charcoal production. Using an indirect approach we combine kiln maps and field information on charcoal making to describe the magnitude and intensity of forest degradation linked to charcoal production, including aboveground biomass and carbon emissions. Our findings reveal that forest degradation associated to charcoal production in the study area is largely independent from deforestation driven by agricultural expansion and that its impact on forest cover change is in the same order of magnitude as deforestation. Our work illustrates the feasibility of using estimates of urban charcoal consumption to establish a link between urban energy demands and forest degradation. This kind of approach has potential to reduce uncertainties in forest cover change and carbon emission assessments in sub-Saharan Africa.

  18. Is the water footprint an appropriate tool for forestry and forest products: the Fennoscandian case.

    PubMed

    Launiainen, Samuli; Futter, Martyn N; Ellison, David; Clarke, Nicholas; Finér, Leena; Högbom, Lars; Laurén, Ari; Ring, Eva

    2014-03-01

    The water footprint by the Water Footprint Network (WF) is an ambitious tool for measuring human appropriation and promoting sustainable use of fresh water. Using recent case studies and examples from water-abundant Fennoscandia, we consider whether it is an appropriate tool for evaluating the water use of forestry and forest-based products. We show that aggregating catchment level water consumption over a product life cycle does not consider fresh water as a renewable resource and is inconsistent with the principles of the hydrologic cycle. Currently, the WF assumes that all evapotranspiration (ET) from forests is a human appropriation of water although ET from managed forests in Fennoscandia is indistinguishable from that of unmanaged forests. We suggest that ET should not be included in the water footprint of rain-fed forestry and forest-based products. Tools for sustainable water management should always contextualize water use and water impacts with local water availability and environmental sensitivity.

  19. Avian research on U.S. Forest Service Experimental Forests and Ranges: Emergent themes, opportunities, and challenges

    USGS Publications Warehouse

    Stoleson, S.H.; King, D.I.; Tomosy, M.

    2011-01-01

    Since 1908, U.S. Forest Service Experimental Forests and Ranges have been dedicated to long-term interdisciplinary research on a variety of ecological and management questions. They encompass a wide diversity of life zones and ecoregions, and provide access to research infrastructure, opportunities for controlled manipulations, and integration with other types of long-term data. These features have facilitated important advances in a number of areas of avian research, including furthering our understanding of population dynamics, the effects of forest management on birds, avian responses to disturbances such as fire and hurricanes, and other aspects of avian ecology and conservation. However, despite these contributions, this invaluable resource has been underutilized by ornithologists. Most of the Experimental Forests and Ranges have had no ornithological work done on them. We encourage the ornithological community, especially graduate students and new faculty, to take advantage of this largely untapped potential for long-term work, linkage with long-term data sets, multiple disciplines, and active forest management. ?? 2010 Elsevier B.V.

  20. Area of old-growth forests in California, Oregon, and Washington. Forest Service research bulletin

    SciTech Connect

    Bolsinger, C.L.; Waddell, K.L.

    1993-12-01

    An area of old-growth forests in California, Oregon, and Washington has declined significantly in the second half of the 20th century. The report summarizes available information on old-growth forest area by ownership in California, Oregon, and Washington. Old-growth definitions used by the various owners and agencies are provided.

  1. Disturbance, complexity, and succession of net ecosystem production in North America’s temperate deciduous forests

    SciTech Connect

    Gough, Christopher; Curtis, Peter; Hardiman, Brady; Scheuermann, Cynthia; Bond-Lamberty, Benjamin

    2016-06-29

    Century-old forests in the U.S. upper Midwest and Northeast power much of North Amer- ica’s terrestrial carbon (C) sink, but these forests’ production and C sequestration capacity are expected to soon decline as fast-growing early successional species die and are replaced by slower growing late successional species. But will this really happen? Here we marshal empirical data and ecological theory to argue that substantial declines in net ecosystem production (NEP) owing to reduced forest growth, or net primary production (NPP), are not imminent in regrown temperate deciduous forests over the next several decades. Forest age and production data for temperate deciduous forests, synthesized from published literature, suggest slight declines in NEP and increasing or stable NPP during middle successional stages. We revisit long-held hypotheses by EP Odum and others that suggest low-severity, high-frequency disturbances occurring in the region’s aging forests will, against intuition, maintain NEP at higher-than- expected rates by increasing ecosystem complexity, sustaining or enhancing NPP to a level that largely o sets rising C losses as heterotrophic respiration increases. This theoretical model is also supported by biological evidence and observations from the Forest Accelerated Succession Experiment in Michigan, USA. Ecosystems that experience high-severity disturbances that simplify ecosystem complexity can exhibit substantial declines in production during middle stages of succession. However, observations from these ecosystems have exerted a disproportionate in uence on assumptions regarding the trajectory and magnitude of age-related declines in forest production. We conclude that there is a wide ecological space for forests to maintain NPP and, in doing so, lessens the declines in NEP, with signi cant implications for the future of the North American carbon sink. Our intellectual frameworks for understanding forest C cycle dynamics and resilience need to

  2. Normalizing Landsat and ASTER Data Using MODIS Data Products for Forest Change Detection

    NASA Technical Reports Server (NTRS)

    Gao, Feng; Masek, Jeffrey G.; Wolfe, Robert E.; Tan, Bin

    2010-01-01

    Monitoring forest cover and its changes are a major application for optical remote sensing. In this paper, we present an approach to integrate Landsat, ASTER and MODIS data for forest change detection. Moderate resolution (10-100m) images (e.g. Landsat and ASTER) acquired from different seasons and times are normalized to one "standard" date using MODIS data products as reference. The normalized data are then used to compute forest disturbance index for forest change detection. Comparing to the results from original data, forest disturbance index from the normalized images is more consistent spatially and temporally. This work demonstrates an effective approach for mapping forest change over a large area from multiple moderate resolution sensors on various acquisition dates.

  3. Forest stand structure, productivity, and age mediate climatic effects on aspen decline.

    PubMed

    Bell, David M; Bradford, John B; Lauenroth, William K

    2014-08-01

    Because forest stand structure, age, and productivity can mediate the impacts of climate on quaking aspen (Populus tremuloides) mortality, ignoring stand-scale factors limits inference on the drivers of recent sudden aspen decline. Using the proportion of aspen trees that were dead as an index of recent mortality at 841 forest inventory plots, we examined the relationship of this mortality index to forest structure and climate in the Rocky Mountains and Intermountain Western United States. We found that forest structure explained most of the patterns in mortality indices, but that variation in growing-season vapor pressure deficit and winter precipitation over the last 20 years was important. Mortality index sensitivity to precipitation was highest in forests where aspen exhibited high densities, relative basal areas, quadratic mean diameters, and productivities, whereas sensitivity to vapor pressure deficit was highest in young forest stands. These results indicate that the effects of drought on mortality may be mediated by forest stand development, competition with encroaching conifers, and physiological vulnerabilities of large trees to drought. By examining mortality index responses to both forest structure and climate, we show that forest succession cannot be ignored in studies attempting to understand the causes and consequences of sudden aspen decline.

  4. Forest stand structure, productivity, and age mediate climatic effects on aspen decline

    USGS Publications Warehouse

    Bell, David M.; Bradford, John B.; Lauenroth, William K.

    2014-01-01

    Because forest stand structure, age, and productivity can mediate the impacts of climate on quaking aspen (Populus tremuloides) mortality, ignoring stand-scale factors limits inference on the drivers of recent sudden aspen decline. Using the proportion of aspen trees that were dead as an index of recent mortality at 841 forest inventory plots, we examined the relationship of this mortality index to forest structure and climate in the Rocky Mountains and Intermountain Western United States. We found that forest structure explained most of the patterns in mortality indices, but that variation in growing-season vapor pressure deficit and winter precipitation over the last 20 years was important. Mortality index sensitivity to precipitation was highest in forests where aspen exhibited high densities, relative basal areas, quadratic mean diameters, and productivities, whereas sensitivity to vapor pressure deficit was highest in young forest stands. These results indicate that the effects of drought on mortality may be mediated by forest stand development, competition with encroaching conifers, and physiological vulnerabilities of large trees to drought. By examining mortality index responses to both forest structure and climate, we show that forest succession cannot be ignored in studies attempting to understand the causes and consequences of sudden aspen decline.

  5. Emergent Patterns of Forest Biomass Production from Across and within a Micro-Network

    NASA Astrophysics Data System (ADS)

    Pederson, N.; Martin Benito, D.; Bishop, D. A.; Dawson, A.; Dietze, M.; Druckenbrod, D.; Dye, A.; Gonzalez, A. C.; Hessl, A. E.; Martin Fernandez, J.; McLachlan, J. S.; Paciorek, C. J.; Poulter, B.; Williams, J. W.

    2014-12-01

    Many factors drive short- and long-term trends in forest biomass production. Replication at multiple scales, from within individual trees up to continental scales, is necessary to determine factors of growth and at what scale they are most important. Here we report on patterns of biomass production from within and across a micro-network of three forests in the northeastern US. Each forest has different histories and species composition, but each is within a similar climatological setting, which gives insight on important factors of short- and long-term patterns of forest production. One emergent pattern is that two forests are showing a large uptick in production over the last decade. Coincident to this uptick, late-season biomass production is showing a significant increase, even among 150-200+ year old trees. The third forest experienced a severe ice storm in the early-Aughts that paused a three-decade trend of increasing production. In the least diverse forest, the most dominant species drives most of the annual to decadal trend in production. In the most diverse forest, no one species appears to be driving landscape-level production, yet the emergent pattern of production reflects not only drought and pluvial events, but the impact of invasive species and the ice storm. Variation in annual biomass production for most species is strongly related to annual variations in soil moisture. Interestingly at the species level, coherency of growth among yellow birch is lower in the oldest forest in which is it is common versus the youngest forest. Differences in coherency suggest different drivers operating at different scales. Growth of red maple is also driven by moisture, but competition appears to be driving a long-term decline of individuals below the canopy. The decline begins soon after a severe defoliation event. In this same forest, however, significant wetting and warming over the last two decades appears to have reduced some of the climatic constraints on red

  6. An imperative need for global change research in tropical forests.

    PubMed

    Zhou, Xuhui; Fu, Yuling; Zhou, Lingyan; Li, Bo; Luo, Yiqi

    2013-09-01

    Tropical forests play a crucial role in regulating regional and global climate dynamics, and model projections suggest that rapid climate change may result in forest dieback or savannization. However, these predictions are largely based on results from leaf-level studies. How tropical forests respond and feedback to climate change is largely unknown at the ecosystem level. Several complementary approaches have been used to evaluate the effects of climate change on tropical forests, but the results are conflicting, largely due to confounding effects of multiple factors. Although altered precipitation and nitrogen deposition experiments have been conducted in tropical forests, large-scale warming and elevated carbon dioxide (CO2) manipulations are completely lacking, leaving many hypotheses and model predictions untested. Ecosystem-scale experiments to manipulate temperature and CO2 concentration individually or in combination are thus urgently needed to examine their main and interactive effects on tropical forests. Such experiments will provide indispensable data and help gain essential knowledge on biogeochemical, hydrological and biophysical responses and feedbacks of tropical forests to climate change. These datasets can also inform regional and global models for predicting future states of tropical forests and climate systems. The success of such large-scale experiments in natural tropical forests will require an international framework to coordinate collaboration so as to meet the challenges in cost, technological infrastructure and scientific endeavor.

  7. Amazon Forests Response to Droughts: A Perspective from the MAIAC Product

    NASA Technical Reports Server (NTRS)

    Bi, Jian; Myneni, Ranga; Lyapustin, Alexei; Wang, Yujie; Park, Taejin; Chi, Chen; Yan, Kai; Knyazikhin, Yuri

    2016-01-01

    Amazon forests experienced two severe droughts at the beginning of the 21st century: one in 2005 and the other in 2010. How Amazon forests responded to these droughts is critical for the future of the Earth's climate system. It is only possible to assess Amazon forests' response to the droughts in large areal extent through satellite remote sensing. Here, we used the Multi-Angle Implementation of Atmospheric Correction (MAIAC) Moderate Resolution Imaging Spectroradiometer (MODIS) vegetation index (VI) data to assess Amazon forests' response to droughts, and compared the results with those from the standard (Collection 5 and Collection 6) MODIS VI data. Overall, the MAIAC data reveal more realistic Amazon forests inter-annual greenness dynamics than the standard MODIS data. Our results from the MAIAC data suggest that: (1) the droughts decreased the greenness (i.e., photosynthetic activity) of Amazon forests; (2) the Amazon wet season precipitation reduction induced by El Niño events could also lead to reduced photosynthetic activity of Amazon forests; and (3) in the subsequent year after the water stresses, the greenness of Amazon forests recovered from the preceding decreases. However, as previous research shows droughts cause Amazon forests to reduce investment in tissue maintenance and defense, it is not clear whether the photosynthesis of Amazon forests will continue to recover after future water stresses, because of the accumulated damages caused by the droughts.

  8. Productivity of ephemeral headwater riparian forests impacted by sedimentation in the southeastern United States coastal plain.

    PubMed

    Jolley, Rachel L; Lockaby, B Graeme; Cavalcanti, Guadalupe G

    2009-01-01

    Riparian forests serve an essential function in improving water quality through the filtering of sediments and nutrients from surface runoff. However, little is known about the impact of sediment deposition on productivity of riparian forests. Sediment inputs may act as a subsidy to forest productivity by providing additional nutrients for plant uptake or may act as a stress by creating anoxic soil conditions. This study determined how sediment deposition affected riparian forests along ephemeral headwater streams at Ft. Benning, Georgia, USA. Above- and belowground productivity, leaf-area index (LAI), and standing crop biomass for fine roots, shrubs, and trees were compared along a gradient of present sedimentation rates in 17 riparian forests. Annual litterfall production was determined from monthly collections using 0.25- m(2) traps; woody biomass was determined from annual diameter at breast height (DBH) measurements using species-specific allometric equations; fine root productivity was determined using sequential coring; LAI was measured by expanding specific leaf area by annual litterfall production; and shrub biomass was determined using species-specific biomass equations based on height and root collar diameter. Significant declines in litterfall, woody biomass production, fine root production, LAI, and shrub biomass were found with as little as 0.1 to 0.4 cm yr(-2) sedimentation. We conclude that the levels of sedimentation in this study do not subsidize growth in ephemeral headwater riparian forests but instead create a stress similar to that found under flooded conditions.

  9. Mapping landscape scale variations of forest structure, biomass, and productivity in Amazonia

    NASA Astrophysics Data System (ADS)

    Saatchi, S.; Malhi, Y.; Zutta, B.; Buermann, W.; Anderson, L. O.; Araujo, A. M.; Phillips, O. L.; Peacock, J.; Ter Steege, H.; Lopez Gonzalez, G.; Baker, T.; Arroyo, L.; Almeida, S.; Higuchi, N.; Killeen, T.; Monteagudo, A.; Neill, D.; Pitman, N.; Prieto, A.; Salomão, R.; Silva, N.; Vásquez Martínez, R.; Laurance, W.; Ramírez, H. A.

    2009-06-01

    Landscape and environmental variables such as topography, geomorphology, soil types, and climate are important factors affecting forest composition, structure, productivity, and biomass. Here, we combine a network of forest inventories with recently developed global data products from satellite observations in modeling the potential distributions of forest structure and productivity in Amazonia and examine how geomorphology, soil, and precipitation control these distributions. We use the RAINFOR network of forest plots distributed in lowland forests across Amazonia, and satellite observations of tree cover, leaf area index, phenology, moisture, and topographical variations. A maximum entropy estimation (Maxent) model is employed to predict the spatial distribution of several key forest structure parameters: basal area, fraction of large trees, fraction of palms, wood density, productivity, and above-ground biomass at 5 km spatial resolution. A series of statistical tests at selected thresholds as well as across all thresholds and jackknife analysis are used to examine the accuracy of distribution maps and the relative contributions of environmental variables. The final maps were interpreted using soil, precipitation, and geomorphological features of Amazonia and it was found that the length of dry season played a key role in impacting the distribution of all forest variables except the wood density. Soil type had a significant impact on the wood productivity. Most high productivity forests were distributed either on less infertile soils of western Amazonia and Andean foothills, on crystalline shields, and younger alluvial deposits. Areas of low elevation and high density of small rivers of Central Amazonia showed distinct features, hosting mainly forests with low productivity and smaller trees.

  10. Forest biorefinery: Potential of poplar phytochemicals as value-added co-products.

    PubMed

    Devappa, Rakshit K; Rakshit, Sudip K; Dekker, Robert F H

    2015-11-01

    The global forestry industry after experiencing a market downturn during the past decade has now aimed its vision towards the integrated biorefinery. New business models and strategies are constantly being explored to re-invent the global wood and pulp/paper industry through sustainable resource exploitation. The goal is to produce diversified, innovative and revenue generating product lines using on-site bioresources (wood and tree residues). The most popular product lines are generally produced from wood fibers (biofuels, pulp/paper, biomaterials, and bio/chemicals). However, the bark and other tree residues like foliage that constitute forest wastes, still remain largely an underexploited resource from which extractives and phytochemicals can be harnessed as by-products (biopharmaceuticals, food additives and nutraceuticals, biopesticides, cosmetics). Commercially, Populus (poplar) tree species including hybrid varieties are cultivated as a fast growing bioenergy crop, but can also be utilized to produce bio-based chemicals. This review identifies and underlines the potential of natural products (phytochemicals) from Populus species that could lead to new business ventures in biorefineries and contribute to the bioeconomy. In brief, this review highlights the importance of by-products/co-products in forest industries, methods that can be employed to extract and purify poplar phytochemicals, the potential pharmaceutical and other uses of >160 phytochemicals identified from poplar species - their chemical structures, properties and bioactivities, the challenges and limitations of utilizing poplar phytochemicals, and potential commercial opportunities. Finally, the overall discussion and conclusion are made considering the recent biotechnological advances in phytochemical research to indicate the areas for future commercial applications from poplar tree species.

  11. Nutritional Products from Space Research

    NASA Technical Reports Server (NTRS)

    1996-01-01

    Six scientists from Martin Marietta who did research for NASA on algae as food supply, oxygen source and a recycling agent for long duration space travel founded Martek Biosciences Corporation. Martek's main product is Formulaid for infants, an algae-based, vegetable-like oil containing two essential polyunsaturated fatty acids known as DHA (docosahexaenoic acid) and ARA (arachidonic acid). The acids are found in human milk but not in most infant formulas, and they are believed to be associated with mental and visual development. Formulaid is on the market in two European countries and licensed to the Mead Johnson Division of Bristol-Myers Squibb, American Home Products and others.

  12. Water resource use and management by the United States forest products industry.

    PubMed

    Wiegand, P S; Flinders, C A; Ice, G G; Malmberg, B J; Fisher, R P

    2009-01-01

    The connections between forest products operations and water resources in the United States is considered and, where possible, quantified. Manufacture of wood, pulp, and paper products and the influences of forest management and forest products manufacture on water quality are discussed. Most fresh water in the US originates in forested areas. Responsible harvesting strategies, best management practices, and forest re-growth combine to minimize or eliminate changes in water availability and degradation of water quality due to harvesting. Relative to alternative land uses and large-scale disturbance events, forested areas produce the highest quality of fresh water. Water inputs for the manufacture of forest products total about 5.8 billion m(3) per year, an amount equal about 0.4% of the surface and groundwater yield from timberland. Approximately 88% of water used in manufacturing is treated and returned directly to surface waters, about 11% is converted to water vapor and released during the manufacturing process, and 1% is imparted to products or solid residuals. Extensive study and continued monitoring of treated effluents suggest few or no concerns regarding the compatibility of current effluents with healthy aquatic systems.

  13. Forest and Agricultural Sector Optimization Model (FASOM): Model structure and policy applications. Forest Service research paper

    SciTech Connect

    Adams, D.M.; Alig, R.J.; Callaway, J.M.; McCarl, B.A.; Winnett, S.M.

    1996-09-01

    The Forest and Agricultural Sector Opimization Model (FASOM) is a dynamic, nonlinear programming model of the forest and agricultural sectors in the United States. The FASOM model initially was developed to evaluate welfare and market impacts of alternative policies for sequestering carbon in trees but also has been applied to a wider range of forest and agricultural sector policy scenarios. The authors describe the model structure and give selected examples of policy applications. A summary of the data sources, input data file format, and the methods used to develop the input data files also are provided.

  14. Wood ant nests as hot spots of carbon dioxide production and cold spots of methane oxidation in temperate forests

    NASA Astrophysics Data System (ADS)

    Jilkova, Veronika; Picek, Tomas; Cajthaml, Tomas; Frouz, Jan

    2016-04-01

    Wood ant nests are known as hot spots of carbon dioxide (CO2) production and are also thought to affect methane (CH4) flux. Stable high temperatures are maintained in ant nests even in cold environments. Here we focused on quantification of CO2 and CH4 flux in wood ant nests, contribution of ants and microbes to CO2 production, properties of nest material that affect CO2 production and the role of ants and microbes in the maintenance of nest temperature. The research was conducted in temperate and boreal forests inhabited by wood ants (Formica s. str.). Gas fluxes were measured either by an infrared gas analyser or a static chamber technique. Ants and nest materials were also incubated in a laboratory. Material properties potentially influencing CO2 flux, such as moisture, nutrient content or temperature were determined. According to the results, CH4 oxidation was lower in wood ant nests than in the surrounding forest soil suggesting that some characteristics of ant nests hinder CH4 oxidation or promote CH4 production. These characteristics were mainly available carbon and nitrogen contents. Wood ant nests clearly are hot spots of CO2 production in temperate forests originating mainly from ant and also from microbial metabolism. Most important properties positively affecting CO2 production were found to be moisture, nutrient content and temperature. Nest temperature is maintained by ant and microbial metabolism; nests from colder environments produce more metabolic heat to maintain similar temperature as nests from warmer environments. In conclusion, as the abundance of wood ant nests in some forests can be very high, ant nests may largely increase heterogeneity in greenhouse gas fluxes in forest ecosystems.

  15. Monitoring Regional Forest Disturbances across the US with Near Real Time MODIS NDVI Products included in the ForWarn Forest Threat Early Warning System

    NASA Astrophysics Data System (ADS)

    Spruce, J.; Hargrove, W. W.; Gasser, J.; Norman, S. P.

    2013-12-01

    Forest threats across the US have become increasingly evident in recent years. These include regionally extensive disturbances (e.g., from drought, bark beetle outbreaks, and wildfires) that can occur across multiyear durations and result in extensive forest mortality. In addition, forests can be subject to ephemeral, sometimes yearly defoliation from various insects and types of storm damage. After prolonged severe disturbance, signs of forest recovery can vary in terms of satellite-based Normalized Difference Vegetation Index (NDVI) values. The increased extent and threat of forest disturbances in part led to the enactment of the 2003 Healthy Forest Restoration Act, which mandated that a national forest threat Early Warning System (EWS) be deployed. In response, the US Forest Service collaborated with NASA, DOE Oak Ridge National Laboratory, and the USGS Eros Data Center to build the near real time ForWarn forest threat EWS for monitoring regionally evident forest disturbances, starting on-line operations in 2010. Given the diversity of disturbance types, severities, and durations, ForWarn employs multiple historical baselines used with current NDVI to derive a suite of six nationwide 'weekly' forest change products. ForWarn uses daily 232 meter MODIS Aqua and Terra satellite NDVI data, including MOD13 products for deriving historical baseline NDVIs and eMODIS products for compiling current NDVI. Separately pre-processing the current and historical NDVIs, the Time Series Product Tool and the Phenological Parameters Estimation Tool are used to temporally reduce noise, fuse, and aggregate MODIS NDVIs into 24 day composites refreshed every 8 days with 46 dates of forest change products per year. The 24 day compositing interval typically enables new disturbances to be detected, while minimizing the frequency of residual atmospheric contamination. ForWarn's three standard forest change products compare current NDVI to that from the previous year, previous 3 years, and

  16. Short and Long Term Impacts of Forest Bioenergy Production on Atmospheric Carbon Dioxide Emissions

    NASA Astrophysics Data System (ADS)

    Hudiburg, T.; Law, B. E.; Luyssaert, S.; Thornton, P. E.

    2011-12-01

    Temperate forest annual net uptake of CO2 from the atmosphere is equivalent to ~16% of the annual fossil fuel emissions in the United States. Mitigation strategies to reduce emissions of carbon dioxide have lead to investigation of alternative sources of energy including forest biomass. The prospect of forest derived bioenergy has led to implementation of new forest management strategies based on the assumption that they will reduce total CO2 emissions to the atmosphere by simultaneously reducing the risk of wildfire and substituting for fossil fuels. The benefit of managing forests for bioenergy substitution of fossil fuels versus potential carbon sequestration by reducing harvest needs to be evaluated. This study uses a combination of Federal Forest Inventory data (FIA), remote sensing, and a coupled carbon-nitrogen ecosystem process model (CLM4-CN) to predict net atmospheric CO2 emissions from forest thinning for bioenergy production in Oregon under varying future management and climate scenarios. We use life-cycle assessment (LCA) incorporating both the forest and forest product sinks and sources of carbon dioxide. Future modeled results are compared with a reduced harvest scenario to determine the potential for increased carbon sequestration in forest biomass. We find that Oregon forests are a current strong sink of 7.5 ± 1.7 Tg C yr-1 or 61 g C m-2 yr-1. (NBP; NEP minus removals from fire and harvest). In the short term, we find that carbon dynamics following harvests for fire prevention and large-scale bioenergy production lead to 2-15% higher emissions over the next 20 years compared to current management, assuming 100% effectiveness of fire prevention. Given the current sink strength, analysis of the forest sector in Oregon demonstrates that increasing harvest levels by all practices above current business-as-usual levels increases CO2 emissions to the atmosphere as long as the region's sink persists. In the long-term, we find that projected changes in

  17. Production costs of biodiversity zones on field and forest margins: a case study in Finland.

    PubMed

    Miettinen, Antti; Hyytiäinen, Kari; Mäkinen, Antti

    2012-07-30

    This paper estimates and compares the costs incurred to a private landowner from establishing and managing 25-m wide biodiversity zones on field and forest margins in southern Finland. Crop and timber prices being at their long-term averages, current agricultural support paid and the real discount rate 3%, the average annual net costs per hectare of field and forest biodiversity zones were €30 ha(-1) and €108 ha(-1), respectively, the field zones being the less costly alternative in 95% of cases. This result is mainly due to the poor productivity of field cultivation relative to timber production under boreal climate conditions. In addition to soil quality, the initial stand structure affects the costs of both biodiversity zone types. It is less costly for a landowner to establish biodiversity zones in forests where no final felling is imminent but which already contain some tree volume. In field biodiversity zones, costs are slightly lower on fields where forest shading is great. Uneven-aged management practiced in forest biodiversity zones was found to lead to a 3-32% reduction in the net present value of forest land compared to conventional forest management. An increase in the real discount rate increases the relative efficiency of forest biodiversity zones.

  18. Eroding forest carbon sinks following thinning for combined fire prevention and bioenergy production

    NASA Astrophysics Data System (ADS)

    Hudiburg, T. W.; Law, B. E.; Luyssaert, S.

    2010-12-01

    Temperate forest annual net uptake of CO2 from the atmosphere is equivalent to ~16% of the annual fossil fuel emissions in the United States. Mitigation strategies to reduce emissions of carbon dioxide have lead to investigation of alternative sources of energy including forest biomass. The prospect of forest derived bioenergy has led to implementation of new forest management strategies based on the assumption that they will reduce total CO2 emissions to the atmosphere by simultaneously reducing the risk of wildfire and substituting for fossil fuels. Using Forest Inventory Analysis (FIA) plot data, regional supplemental plot data, and remote sensing products we determined the carbon stocks and fluxes of West Coast forests under current and proposed management scenarios for a 20 year treatment period. Varying biofuels thinning treatments designed to meet multiple objectives emphasizing fire prevention, economic gain, or energy production were applied to determine the resulting net carbon balance and bioenergy potential. Contrary to the management objectives, we find that increased removals result in substantial decreases in forest carbon stocks and Net Biome Production (NBP) and increased emissions. Thinning forests for energy production is not carbon neutral. Emissions are estimated to increase over the 20-year period because preventive thinning removals exceed the CO2 that would have been emitted due to wildfires, fossil fuel inputs are required for harvest and manufacturing, and use of woody biomass in short-lived products emits large quantities of CO2 to the atmosphere. It has the net effect of releasing otherwise sequestered carbon to the atmosphere, which may effectively reduce ongoing carbon uptake by forests and as a result, increase net greenhouse gas emissions, undermining the objective of greenhouse gas reductions over the next several decades.

  19. Forest Service Career Guide. Professional Opportunities in Natural Resource Management, Planning, and Research. Revised Edition.

    ERIC Educational Resources Information Center

    Forest Service (USDA), Washington, DC.

    The guide provides information on professional opportunities in natural resource management, planning, and research. Reasons for careers in forest service are presented and a brief description of the forest service is provided. Career opportunities in the following areas are described: forestry, engineering, geology, hydrology, landscape…

  20. The forest products industry in southeast Asia: An emphasis on Indonesia

    SciTech Connect

    Choong, E.T. . School of Forestry, Wildlife, and Fisheries); Atmawidjaja, R. . Faculty of Forestry); Achmadi, S.S. . Faculty of Mathematics and Natural Science)

    1993-05-01

    Wood production has increased rapidly in Southeast Asia in recent years. Harvesting intensity has also increased dramatically. To such an extent that the destruction of the tropical rainforest is of great concern to many people. This paper discusses the forest resources of three major wood-producing countries of Southeast Asia: Indonesia, Malaysia, and the Philippines, and the utilization of these resources in world markets. Because Indonesia is now the largest timber producer in the region, special emphasis is placed on the development of its forest products industry. Concern for the tropical forest and the effect of sustainable forestry development on the growth of the forest products industry, the economy, and the social environment are discussed.

  1. Decadal drought deaccelerated the increasing trend of annual net primary production in tropical or subtropical forests in southern China.

    PubMed

    Wang, Wantong; Wang, Jinxia; Liu, Xingzhao; Zhou, Guoyi; Yan, Junhua

    2016-06-30

    Previous investigations have identified that the effects of climate change on net primary production (NPP) of global forests have varied both spatially and temporally, and that warming has increased the NPP for many forests. However, other factors, such as available soil water for plant growth, could limit these incremental responses to warming. In our investigation we have quantified the responses of NPP of tropical or subtropical forests in southern China to warming and drought stress over the past three decades (1981 to 2012) using data from five forest research stations and satellite measurements. NPP, mean annual temperature (MAT) and annual days without rainfall showed an increase of 0.076 g C m(-2) a(-2) (standardized), 0.057 °C a(-1) (standardized) and 0.067 d a(-1) (standardized) during the study period, respectively. However, incremental NPP was deaccelerated at a rate of approximately 20.8% per decade. This deacceleration was primarily caused by a decrease in available soil water which resulted from warming (mainly occurring in winter and autumn) and the changes in rainfall pattern. The result indicates that intensifying drought stress would limit future increases of forest NPP in southern China.

  2. Decadal drought deaccelerated the increasing trend of annual net primary production in tropical or subtropical forests in southern China

    NASA Astrophysics Data System (ADS)

    Wang, Wantong; Wang, Jinxia; Liu, Xingzhao; Zhou, Guoyi; Yan, Junhua

    2016-06-01

    Previous investigations have identified that the effects of climate change on net primary production (NPP) of global forests have varied both spatially and temporally, and that warming has increased the NPP for many forests. However, other factors, such as available soil water for plant growth, could limit these incremental responses to warming. In our investigation we have quantified the responses of NPP of tropical or subtropical forests in southern China to warming and drought stress over the past three decades (1981 to 2012) using data from five forest research stations and satellite measurements. NPP, mean annual temperature (MAT) and annual days without rainfall showed an increase of 0.076 g C m‑2 a‑2 (standardized), 0.057 °C a‑1 (standardized) and 0.067 d a‑1 (standardized) during the study period, respectively. However, incremental NPP was deaccelerated at a rate of approximately 20.8% per decade. This deacceleration was primarily caused by a decrease in available soil water which resulted from warming (mainly occurring in winter and autumn) and the changes in rainfall pattern. The result indicates that intensifying drought stress would limit future increases of forest NPP in southern China.

  3. Decadal drought deaccelerated the increasing trend of annual net primary production in tropical or subtropical forests in southern China

    PubMed Central

    Wang, Wantong; Wang, Jinxia; Liu, Xingzhao; Zhou, Guoyi; Yan, Junhua

    2016-01-01

    Previous investigations have identified that the effects of climate change on net primary production (NPP) of global forests have varied both spatially and temporally, and that warming has increased the NPP for many forests. However, other factors, such as available soil water for plant growth, could limit these incremental responses to warming. In our investigation we have quantified the responses of NPP of tropical or subtropical forests in southern China to warming and drought stress over the past three decades (1981 to 2012) using data from five forest research stations and satellite measurements. NPP, mean annual temperature (MAT) and annual days without rainfall showed an increase of 0.076 g C m−2 a−2 (standardized), 0.057 °C a−1 (standardized) and 0.067 d a−1 (standardized) during the study period, respectively. However, incremental NPP was deaccelerated at a rate of approximately 20.8% per decade. This deacceleration was primarily caused by a decrease in available soil water which resulted from warming (mainly occurring in winter and autumn) and the changes in rainfall pattern. The result indicates that intensifying drought stress would limit future increases of forest NPP in southern China. PMID:27356766

  4. Forest models: their development and potential applications for air pollution effects research

    SciTech Connect

    Shugart, H.H.; McLaughlin, S.B.; West, D.C.

    1980-01-01

    As research tools for evaluating the effects of chronic air pollution stress, forest simulation models offer one means of integrating forest growth and development data with generalized indices of pollution stress. This approach permits consideration of both the competitive interactions of trees in the forest stand and the influences of the stage of stand development on sensitivity of component species. A review of forest growth models, including tree, stand, and gap models, is provided as a means of evaluating relative strengths, weaknesses, and limits of applicability of representative examples of each type. Data from recent simulations with a gap model of eastern deciduous forest responses to air pollution stress are presented to emphasize the potential importance of competition in modifying individual species' responses in a forest stand. Recent developments in dendroecology are discussed as a potential mechanism for model validation and extended application.

  5. Greenhouse gas and carbon profile of the u.s. Forest products industry value chain.

    PubMed

    Heath, Linda S; Maltby, Van; Miner, Reid; Skog, Kenneth E; Smith, James E; Unwin, Jay; Upton, Brad

    2010-05-15

    A greenhouse gas and carbon accounting profile was developed for the U.S. forest products industry value chain for 1990 and 2004-2005 by examining net atmospheric fluxes of CO(2) and other greenhouse gases (GHGs) using a variety of methods and data sources. Major GHG emission sources include direct and indirect (from purchased electricity generation) emissions from manufacturing and methane emissions from landfilled products. Forest carbon stocks in forests supplying wood to the industry were found to be stable or increasing. Increases in the annual amounts of carbon removed from the atmosphere and stored in forest products offset about half of the total value chain emissions. Overall net transfers to the atmosphere totaled 91.8 and 103.5 TgCO(2)-eq. in 1990 and 2005, respectively, although the difference between these net transfers may not be statistically significant. Net transfers were higher in 2005 primarily because additions to carbon stored in forest products were less in 2005. Over this same period, energy-related manufacturing emissions decreased by almost 9% even though forest products output increased by approximately 15%. Several types of avoided emissions were considered separately and were collectively found to be notable relative to net emissions.

  6. Greenhouse Gas and Carbon Profile of the U.S. Forest Products Industry Value Chain

    PubMed Central

    2010-01-01

    A greenhouse gas and carbon accounting profile was developed for the U.S. forest products industry value chain for 1990 and 2004−2005 by examining net atmospheric fluxes of CO2 and other greenhouse gases (GHGs) using a variety of methods and data sources. Major GHG emission sources include direct and indirect (from purchased electricity generation) emissions from manufacturing and methane emissions from landfilled products. Forest carbon stocks in forests supplying wood to the industry were found to be stable or increasing. Increases in the annual amounts of carbon removed from the atmosphere and stored in forest products offset about half of the total value chain emissions. Overall net transfers to the atmosphere totaled 91.8 and 103.5 TgCO2-eq. in 1990 and 2005, respectively, although the difference between these net transfers may not be statistically significant. Net transfers were higher in 2005 primarily because additions to carbon stored in forest products were less in 2005. Over this same period, energy-related manufacturing emissions decreased by almost 9% even though forest products output increased by approximately 15%. Several types of avoided emissions were considered separately and were collectively found to be notable relative to net emissions. PMID:20355695

  7. Microbial nitrogen cycling response to forest-based bioenergy production.

    PubMed

    Minick, Kevan J; Strahm, Brian D; Fox, Thomas R; Sucre, Eric B; Leggett, Zakiya H

    2015-12-01

    Concern over rising atmospheric CO2 and other greenhouse gases due to fossil fuel combustion has intensified research into carbon-neutral energy production. Approximately 15.8 million ha of pine plantations exist across the southeastern United States, representing a vast land area advantageous for bioenergy production without significant landuse change or diversion of agricultural resources from food production. Furthermore, intercropping of pine with bioenergy grasses could provide annually harvestable, lignocellulosic biomass feedstocks along with production of traditional wood products. Viability of such a system hinges in part on soil nitrogen (N) availability and effects of N competition between pines and grasses on ecosystem productivity. We investigated effects of intercropping loblolly pine (Pinus taeda) with switchgrass (Panicum virgatum) on microbial N cycling processes in the Lower Coastal Plain of North Carolina, USA. Soil samples were collected from bedded rows of pine and interbed space of two treatments, composed of either volunteer native woody and herbaceous vegetation (pine-native) or pure switchgrass (pine-switchgrass) in interbeds. An in vitro 15N pool-dilution technique was employed to quantify gross N transformations at two soil depths (0-5 and 5-15 cm) on four dates in 2012-2013. At the 0-5 cm depth in beds of the pine-switchgrass treatment, gross N mineralization was two to three times higher in November and February compared to the pine-native treatment, resulting in increased NH4(+) availability. Gross and net nitrification were also significantly higher in February in the same pine beds. In interbeds of the pine-switchgrass treatment, gross N mineralization was lower from April to November, but higher in February, potentially reflecting positive effects of switchgrass root-derived C inputs during dormancy on microbial activity. These findings indicate soil N cycling and availability has increased in pine beds of the pine

  8. Simulating forest structure, timber production, and socioeconomic effects in a multi-owner province.

    PubMed

    Johnson, K Norman; Bettinger, Pete; Kline, Jeffrey D; Spies, Thomas A; Lennette, Marie; Lettman, Gary; Garber-Yonts, Brian; Larsen, Tad

    2007-01-01

    Protecting biodiversity has become a major goal in managing coastal forests in the Pacific Northwest--an area in which human activities have had a significant influence on landscape change. A complex pattern of public and private forest ownership, combined with new regulations for each owner group, raises questions about how well and how efficiently these policies achieve their biodiversity goals. To develop a deeper understanding of the aggregate effect of forest policies, we simulated forest structures, timber production, and socioeconomic conditions over time for the mixture of private and public lands in the 2.3-million-ha Coast Range Physiographic Province of Oregon. To make these projections, we recognized both vegetative complexity at the stand level and spatial complexity at the landscape level. We focused on the two major factors influencing landscape change in the forests of the Coast Range: (1) land use, especially development for houses and cities, and (2) forest management, especially clearcutting. Our simulations of current policy suggest major changes in land use on the margins of the Coast Range, a divergence in forest structure among the different owners, an increase in old-growth forests, and a continuing loss of the structural elements associated with diverse young forests. Our simulations also suggest that current harvest levels can be approximately maintained, with the harvest coming almost entirely from private lands. A policy alternative that retained live trees for wildlife would increase remnant structures but at a cost to landowners (5-7% reduction in timber production). Another alternative that precluded thinning of plantations on federal land would significantly reduce the area of very large diameter (>75 cm dbh) conifer forests 100 years into the future

  9. National forest trail users: Planning for recreation opportunities. Forest Service research paper (Final)

    SciTech Connect

    Daigle, J.J.; Watson, A.E.; Haas, G.E.

    1994-03-01

    National forest trail users in four geographical regions of the United States are described based on participation in clusters of recreation activities. Visitors are classified into day hiking, undeveloped recreation, and two developed camping and hiking activity clusters for the Appalachian, Pacific, Rocky Mountain, and Southwestern regions. Distance and time traveled to national forest sites from home varied for activity clusters. Length of time at the site varied across activity clusters. Recreation activities combined with home range allows for assessing relative availability of, and demand for, different types of place-related opportunities and experiences users seek within a particular region.

  10. Use of Current 2010 Forest Disturbance Monitoring Products for the Conterminous United States in Aiding a National Forest Threat Early Warning System

    NASA Technical Reports Server (NTRS)

    Spruce, Joseph P.; Hargrove, William; Gasser, J.; Smoot, J.; Kuper, P.

    2010-01-01

    This presentation discusses contributions of near real time (NRT) MODIS forest disturbance detection products for the conterminous United States to an emerging national forest threat early warning system (EWS). The latter is being developed by the USDA Forest Service s Eastern and Western Environmental Threat Centers with help from NASA Stennis Space Center and the Oak Ridge National Laboratory. Building off work done in 2009, this national and regional forest disturbance detection and viewing capability of the EWS employs NRT MODIS NDVI data from the USGS eMODIS group and historical NDVI data from standard MOD13 products. Disturbance detection products are being computed for 24 day composites that are refreshed every 8 days. Products for 2010 include 42 dates of the 24 day composites. For each compositing date, we computed % change in forest maximum NDVI products for 2010 with respect to each of three historical baselines of 2009, 2007-2009, and 2003-2009,. The three baselines enable one to view potential current, recent, and longer term forest disturbances. A rainbow color table was applied to each forest change product so that potential disturbances (NDVI drops) were identified in hot color tones and growth (NDVI gains) in cold color tones. Example products were provided to end-users responsible for forest health monitoring at the Federal and State levels. Large patches of potential forest disturbances were validated based on comparisons with available reference data, including Landsat and field survey data. Products were posted on two internet mapping systems for US Forest Service internal and collaborator use. MODIS forest disturbance detection products were computed and posted for use in as little as 1 day after the last input date of the compositing period. Such products were useful for aiding aerial disturbance detection surveys and for assessing disturbance persistence on both inter- and intra-annual scales. Multiple 2010 forest disturbance events were

  11. Use of Current 2010 Forest Disturbance Monitoring Products for the Conterminous United States in Aiding a National Forest Threat Early Warning System

    NASA Astrophysics Data System (ADS)

    Spruce, J.; Hargrove, W. W.; Gasser, J.; Smoot, J.; Kuper, P.

    2010-12-01

    This presentation discusses contributions of near real time (NRT) MODIS forest disturbance detection products for the conterminous United States to an emerging national forest threat early warning system (EWS). The latter is being developed by the USDA Forest Service’s Eastern and Western Environmental Threat Centers with help from NASA Stennis Space Center and the Oak Ridge National Laboratory. Building off work done in 2009, this national and regional forest disturbance detection and viewing capability of the EWS employs NRT MODIS NDVI data from the USGS eMODIS group and historical NDVI data from standard MOD13 products. Disturbance detection products are being computed for 24 day composites that are refreshed every 8 days. Products for 2010 include 42 dates of the 24 day composites. For each compositing date, we computed % change in forest maximum NDVI products for 2010 with respect to each of three historical baselines of 2009, 2007-2009, and 2003-2009. The three baselines enable one to view potential current, recent, and longer term forest disturbances. A rainbow color table was applied to each forest change product so that potential disturbances (NDVI drops) were identified in hot color tones and growth (NDVI gains) in cold color tones. Example products were provided to end-users responsible for forest health monitoring at the Federal and State levels. Large patches of potential forest disturbances were validated based on comparisons with available reference data, including Landsat and field survey data. Products were posted on two internet mapping systems for US Forest Service internal and collaborator use. MODIS forest disturbance detection products were computed and posted for use in as little as 1 day after the last input date of the compositing period. Such products were useful for aiding aerial disturbance detection surveys and for assessing disturbance persistence on both inter- and intra-annual scales. Multiple 2010 forest disturbance events were

  12. Data Archive of the Harvard Forest, a Long Term Ecological Research (LTER) Site

    DOE Data Explorer

    Since 1907 research and education have been the mission of the Harvard Forest is one of the oldest and most intensively studied forests in North America. Located in Petersham, Massachusetts, its 3000 acres of land have been a center of research and education since 1907. The Long Term Ecological Research (LTER) program, established in 1988 and funded by the National Science Foundation, provides a framework for much of this activity. An understanding of forest responses to natural and human disturbance and environmental change over broad spatial and temporal scales pulls together research topics including biodiversity studies, the effects of invasive organisms, large experiments and permanent plot studies, historical and retrospective studies, soil nutrient dynamics, and plant population and community ecological interactions. Major research in forest-atmosphere exchange, hydrology, and regional studies places the work in regional and global context, aided by modeling tools. Conservation and management research and linkages to policy have been part of the Forest since its beginning, and the approaches used in New England can often apply to international studies. [Copied from http://harvardforest.fas.harvard.edu/research.html] In addition to more than 150 datasets, the Visual Information Access system at Harvard University Library makes nearly 900 images pertaining to Harvard Forest research available online to the public.

  13. Monitoring Regional Forest Disturbances across the US with near Real Time MODIS NDVI Products Resident to the ForWarn Forest Threat Early Warning System

    NASA Technical Reports Server (NTRS)

    Spruce, Joseph P.; Hargrove, William W.; Gasser, Gerald

    2013-01-01

    Forest threats across the US have become increasingly evident in recent years. Sometimes these have resulted in regionally evident disturbance progressions (e.g., from drought, bark beetle outbreaks, and wildfires) that can occur across multiyear durations and have resulted in extensive forest overstory mortality. In addition to stand replacement disturbances, other forests are subject to ephemeral, sometimes yearly defoliation from various insects and varying types and intensities of ephemeral damage from storms. Sometimes, after prolonged severe disturbance, signs of recovery in terms of Normalized Difference Vegetation Index (NDVI) can occur. The growing prominence and threat of forest disturbances in part have led to the formation and implementation of the 2003 Healthy Forest Restoration Act which mandated that national forest threat early warning system be developed and deployed. In response, the US Forest Service collaborated with NASA, DOE Oakridge National Laboratory, and the USGS Eros Data Center to build and roll-out the near real time ForWarn early warning system for monitoring regionally evident forest disturbances. Given the diversity of disturbance types, severities, and durations, ForWarn employs multiple historical baselines that are used with current NDVI to derive a suite of six forest change products that are refreshed every 8 days. ForWarn employs daily quarter kilometer MODIS NDVI data from the Aqua and Terra satellites, including MOD13 data for deriving historical baseline NDVIs and eMODIS 7 NDVI for compiling current NDVI. In doing so, the Time Series Product Tool and the Phenological Parameters Estimation Tool are used to temporally de-noise, fuse, and aggregate current and historical MODIS NDVIs into 24 day composites refreshed every 8 days with 46 dates of products per year. The 24 day compositing interval enables disturbances to be detected, while minimizing the frequency of residual atmospheric contamination. Forest change products are

  14. Research in Support of Forest Management. Final report, 1986--1991

    SciTech Connect

    Marx, D.H.

    1991-12-01

    This final research report on Research in Support of Forest Management for the Savannah River Forest Station covers the period 1986 thru 1991. This report provides a list of publications resulting from research accomplished by SEFES scientists and their cooperators, and a list of continuing research study titles. Output is 22 research publications, 23 publications involving technology transfer of results to various user groups, and 11 manuscripts in pre-publication format. DOE funding contributed approximately 15 percent of the total cost of the research.

  15. Political Shifts and Forest Transitions: A Review and Theoretical Framework for Future Research

    NASA Astrophysics Data System (ADS)

    Ordway, E.

    2015-12-01

    Most armed conflicts in recent history have occurred in biodiversity hotspots. Yet, studies examining impacts of warfare on forests yield contradictory results making it difficult to decipher trends and patterns. This study provides a theoretical framework that can be used to clarify hypothetical relationships between conflict and forest transitions, contributing to our ability to push forward a growing field of research on environmental change and conflict. Landsat TM and ETM+ satellite data were analyzed to examine forest transitions in Rwanda during a conflict and post conflict period. Net trends showed little difference between periods, with a rate of 1.6% annual gain in forest cover during conflict years, and 2.5% after the conflict. Further investigation revealed spatially concentrated forest loss during conflict years; 96% of forest loss occurred in protected areas with the most loss in Gishwati Forest Reserve at a rate of 6.1%. Trends were explored using spatially explicit conflict data that distinguished armed conflict activity from conflict induced settlements. Impacts of conflict on forests in Rwanda appear to be influenced by natural resource use near settlements. Massive migrations of people into settlements during the conflict, who had previously been scattered across the landscape, likely resulted in a redistribution of pressures. Reduced pressure elsewhere supports this inference. Results underscore the vulnerability of protected areas and the spatial dynamics of forest resource dependence during conflicts. This work demonstrates the value of distinguishing conflict activities to assess their varied environmental effects, and contributes to our theoretical development of environmental change and conflict.

  16. The linkages between photosynthesis, productivity, growth and biomass in lowland Amazonian forests.

    PubMed

    Malhi, Yadvinder; Doughty, Christopher E; Goldsmith, Gregory R; Metcalfe, Daniel B; Girardin, Cécile A J; Marthews, Toby R; Del Aguila-Pasquel, Jhon; Aragão, Luiz E O C; Araujo-Murakami, Alejandro; Brando, Paulo; da Costa, Antonio C L; Silva-Espejo, Javier E; Farfán Amézquita, Filio; Galbraith, David R; Quesada, Carlos A; Rocha, Wanderley; Salinas-Revilla, Norma; Silvério, Divino; Meir, Patrick; Phillips, Oliver L

    2015-06-01

    Understanding the relationship between photosynthesis, net primary productivity and growth in forest ecosystems is key to understanding how these ecosystems will respond to global anthropogenic change, yet the linkages among these components are rarely explored in detail. We provide the first comprehensive description of the productivity, respiration and carbon allocation of contrasting lowland Amazonian forests spanning gradients in seasonal water deficit and soil fertility. Using the largest data set assembled to date, ten sites in three countries all studied with a standardized methodology, we find that (i) gross primary productivity (GPP) has a simple relationship with seasonal water deficit, but that (ii) site-to-site variations in GPP have little power in explaining site-to-site spatial variations in net primary productivity (NPP) or growth because of concomitant changes in carbon use efficiency (CUE), and conversely, the woody growth rate of a tropical forest is a very poor proxy for its productivity. Moreover, (iii) spatial patterns of biomass are much more driven by patterns of residence times (i.e. tree mortality rates) than by spatial variation in productivity or tree growth. Current theory and models of tropical forest carbon cycling under projected scenarios of global atmospheric change can benefit from advancing beyond a focus on GPP. By improving our understanding of poorly understood processes such as CUE, NPP allocation and biomass turnover times, we can provide more complete and mechanistic approaches to linking climate and tropical forest carbon cycling.

  17. AmeriFlux US-Prr Poker Flat Research Range Black Spruce Forest

    SciTech Connect

    Suzuki, Rikie

    2016-01-01

    This is the AmeriFlux version of the carbon flux data for the site US-Prr Poker Flat Research Range Black Spruce Forest. Site Description - This site is located in a blackspruce forest within the property of the Poker Flat Research Range, University of Alaska, Fairbanks. Time-lapse image of the canopy is measured at the same time to relate flux data to satellite images.

  18. VARIABILITY IN NET PRIMARY PRODUCTION AND CARBON STORAGE IN BIOMASS ACROSS OREGON FORESTS - AN ASSESSMENT INTEGRATING DATA FROM FOREST INVENTORIES, INTENSIVE SITES, AND REMOTE SENSING. (R828309)

    EPA Science Inventory

    We used a combination of data from USDA Forest Service inventories, intensive
    chronosequences, extensive sites, and satellite remote sensing, to estimate biomass
    and net primary production (NPP) for the forested region of western Oregon. The
    study area was divided int...

  19. The production of phytolith-occluded carbon in China's forests: implications to biogeochemical carbon sequestration.

    PubMed

    Song, Zhaoliang; Liu, Hongyan; Li, Beilei; Yang, Xiaomin

    2013-09-01

    The persistent terrestrial carbon sink regulates long-term climate change, but its size, location, and mechanisms remain uncertain. One of the most promising terrestrial biogeochemical carbon sequestration mechanisms is the occlusion of carbon within phytoliths, the silicified features that deposit within plant tissues. Using phytolith content-biogenic silica content transfer function obtained from our investigation, in combination with published silica content and aboveground net primary productivity (ANPP) data of leaf litter and herb layer in China's forests, we estimated the production of phytolith-occluded carbon (PhytOC) in China's forests. The present annual phytolith carbon sink in China's forests is 1.7 ± 0.4 Tg CO2  yr(-1) , 30% of which is contributed by bamboo because the production flux of PhytOC through tree leaf litter for bamboo is 3-80 times higher than that of other forest types. As a result of national and international bamboo afforestation and reforestation, the potential of phytolith carbon sink for China's forests and world's bamboo can reach 6.8 ± 1.5 and 27.0 ± 6.1 Tg CO2  yr(-1) , respectively. Forest management practices such as bamboo afforestation and reforestation may significantly enhance the long-term terrestrial carbon sink and contribute to mitigation of global climate warming.

  20. Forest production predicted from satellite image analysis for the Southeast Asia region

    PubMed Central

    2013-01-01

    Background The objective of this study was to demonstrate a new, cost-effective method to define the sustainable amounts of harvested wood products in Southeast Asian countries case studies, while avoiding degradation (net loss) of total wood carbon stocks. Satellite remote sensing from the MODIS sensor was used in the CASA (Carnegie Ames Stanford Approach) carbon cycle model to map forest production for the Southeast Asia region from 2000 to 2010. These CASA model results have been designed to be spatially detailed enough to support carbon cycle assessments in different wooded land cover classes, e.g., open woodlands, wetlands, and forest areas. Results The country with the highest average forest net primary production (NPP greater than 950 g C m-2 yr-1) over the period was the Philippines, followed by Malaysia and Indonesia. Myanmar and Vietnam had the lowest average forest NPP among the region’s countries at less than 815 g C m-2 yr-1. Case studies from throughout the Southeast Asia region for the maximum harvested wood products amount that could be sustainably extracted per year were generated using the CASA model NPP predictions. Conclusions The method of using CASA model’s estimated annual change in forest carbon on a yearly basis can conservatively define the upper limit for the amount of harvested wood products that can be removed and still avoid degradation (net loss) of the total wood carbon stock over that same time period. PMID:24016254

  1. An exploratory assessment of the attitudes of Chinese wood products manufacturers towards forest certification.

    PubMed

    Chen, Juan; Innes, John L; Kozak, Robert A

    2011-11-01

    Interviews with Chinese forest products manufacturers were conducted to explore their attitudes towards forest certification and related issues. Participants comprised owners, CEOs, and managers in 20 Chinese wood products companies, including producers of furniture, doors, flooring, and various engineered wood products. The interviews were used to analyze the extent to which participants were considering adopting forest certification and what might motivate such a decision. This was done by assessing their awareness and knowledge of certification. The results indicated that participants' understanding of forest certification was extremely low, despite major efforts in China to raise awareness of the issue. Potential economic benefits were the most frequently cited reason to adopt certification, including gaining or maintaining competitive advantage over their industry counterparts, improved access to both domestic and export markets, better customer recognition, and enhanced corporate responsibility practices. Some interviewees (3 out of 20) considered that certification would become a mandatory requirement or industry standard, and that this would be the only viable motivation for certification given that the financial benefits were potentially limited. According to the participants, the main differences between certified and uncertified wood products operations related to improved market access and public image. Interviewees felt that cooperation between and support from governments and the forest industry would enable the enhanced awareness of certification amongst manufacturers and the general public. This, in turn, could serve to stimulate demand for certified products.

  2. Sensitivity of tropical forest aboveground productivity to climate anomalies in SW Costa Rica

    NASA Astrophysics Data System (ADS)

    Hofhansl, Florian; Kobler, Johannes; Ofner, Joachim; Drage, Sigrid; Pölz, Eva-Maria; Wanek, Wolfgang

    2014-12-01

    The productivity of tropical forests is driven by climate (precipitation, temperature, and light) and soil fertility (geology and topography). While large-scale drivers of tropical productivity are well established, knowledge on the sensitivity of tropical lowland net primary production to climate anomalies remains scarce. We here analyze seven consecutive years of monthly recorded tropical forest aboveground net primary production (ANPP) in response to a recent El Niño-Southern Oscillation (ENSO) anomaly. The ENSO transition period resulted in increased temperatures and decreased precipitation during the El Niño dry period, causing a decrease in ANPP. However, the subsequent La Niña wet period caused strong increases in ANPP such that drought-induced reductions were overcompensated. Most strikingly, the climatic controls differed between canopy production (CP) and wood production (WP). Whereas CP showed strong seasonal variation but was not affected by ENSO, WP decreased significantly in response to a 3°C increase in annual maximum temperatures during the El Niño period but subsequently recovered to above predrought levels during the La Niña period. Moreover, the climate sensitivity of tropical forest ANPP components was affected by local topography (water availability) and disturbance history (species composition). Our results suggest that projected increases in temperature and dry season length could impact tropical carbon sequestration by shifting ANPP partitioning toward decreased WP, thus decreasing the carbon storage of highly productive lowland forests. We conclude that the impact of climate anomalies on tropical forest productivity is strongly related to local site characteristics and will therefore likely prevent uniform responses of tropical lowland forests to projected global changes.

  3. Accounting for forest carbon pool dynamics in product carbon footprints: Challenges and opportunities

    SciTech Connect

    Newell, Joshua P.; Vos, Robert O.

    2012-11-15

    Modification and loss of forests due to natural and anthropogenic disturbance contribute an estimated 20% of annual greenhouse gas (GHG) emissions worldwide. Although forest carbon pool modeling rarely suggests a 'carbon neutral' flux profile, the life cycle assessment community and associated product carbon footprint protocols have struggled to account for the GHG emissions associated with forestry, specifically, and land use generally. Principally, this is due to underdeveloped linkages between life cycle inventory (LCI) modeling for wood and forest carbon modeling for a full range of forest types and harvest practices, as well as a lack of transparency in globalized forest supply chains. In this paper, through a comparative study of U.S. and Chinese coated freesheet paper, we develop the initial foundations for a methodology that rescales IPCC methods from the national to the product level, with reference to the approaches in three international product carbon footprint protocols. Due to differences in geographic origin of the wood fiber, the results for two scenarios are highly divergent. This suggests that both wood LCI models and the protocols need further development to capture the range of spatial and temporal dimensions for supply chains (and the associated land use change and modification) for specific product systems. The paper concludes by outlining opportunities to measure and reduce uncertainty in accounting for net emissions of biogenic carbon from forestland, where timber is harvested for consumer products. - Highlights: Black-Right-Pointing-Pointer Typical life cycle assessment practice for consumer products often excludes significant land use change emissions when estimating carbon footprints. Black-Right-Pointing-Pointer The article provides a methodology to rescale IPCC guidelines for product-level carbon footprints. Black-Right-Pointing-Pointer Life cycle inventories and product carbon footprint protocols need more comprehensive land use

  4. Neotropical primate communities: Effects of disturbance, resource production and forest type heterogeneity.

    PubMed

    Stevenson, Pablo R

    2015-12-18

    Undisturbed primate communities in the Neotropics are bottom-up structured as their biomass and species richness can be predicted from fruit production. However, the effects of fruit scarcity and the availability of forest types have not been fully analyzed, and seasonality is expected to differently affect small and large monkeys. The first aim of this study was to examine the effect of contrasting forest types within a location on the temporal variation in fruit production. The second was to assess the relative roles of disturbance, climate, patterns of fruit and leaf production, and plant composition on determining Neotropical primate communities. I compiled population density data for diurnal primate species from 154 sites to calculate species richness and assemblage biomass. Fruit abundance in the study sites was estimated from fruit trap data and phenology transects, and fruit variability was calculated as the monthly coefficient of variation (CV) and the length of the fruit scarcity period (LFSP). The results indicate that fruit production in floodplain forests is generally more variable than in terra firme forests, and this variation decreases in habitats with mixed forest types. Endozoochorous fruit production (based on fruit traps) and litter productivity were good predictors of the biomass of Neotropical primates (R(2)  = 0.83 and R(2)  = 0.59, respectively), but neither CV nor LFSP were good predictors. The biomass of large primates was independent of rainfall variation, but the biomass of small and medium sized monkeys was negatively correlated with temporal rainfall variability. Varzea forests tended to show higher biomass than those from terra firme and igapó. These results suggest that the production of fleshy fruits is the best predictor of the structure of primate assemblages in the Neotropics, but the effect of leaf quality and productivity remains to be investigated. Am. J. Primatol. © 2015 Wiley Periodicals, Inc.

  5. [Carbon density and production in valley spruce-fir forest in Xiaoxing'an Mountains, China].

    PubMed

    Cai, Hui-Ying; Di, Xue-Ying; Jin, Guang-Ze

    2014-10-01

    The carbon density and production were measured using both forest inventory and allometry approaches in the declining valley spruce-fir forest in Xiaoxing' an Mountains. Results showed that the total carbon density of the forest was 268. 14 t C · hm(-2) in 2011, and carbon densities of the vegetation, detritus and soil were 74.25, 16.86 and 177.03 t C · hm(-2), respectively. From 2006 to 2011, tree layer carbon density decreased from 80.86 t C · hm(-2) to 71.73 t C · hm(-2). The average decrease proportions per year of carbon density were 0.5%, 1.2%, 2.7% and 3.7% for Abies nephrolepis, Betula platyphylla, Picea spp., and Larix gmelinii, respectively. However, carbon densities were increased by 2.9%, 3.9% and 7.2% per year for Alnus sibirica, Pinus koraiensis and Acer ukurunduense, respectively. Net primary production (NPP) of the forest was 4.69 t C · hm(-2) · a(-1). The ratio of belowground NPP to aboveground NPP was 0.56. Litterfall accounted for the largest proportion of the NPP of forest with a value of 34.5%. As the two most important carbon output approaches of forest ecosystems, the fluxes of heterotrophic respiration and coarse woody debris decomposition were 293.67 and 119.29 g C · m(-2) · a(-1), respectively. Net ecosystem production (NEP) of the forest was 55.90 g C · m(-2) a(-1). The results indicated that the valley spruce-fir forest in the declining state still had a certain carbon sink capacity.

  6. Disturbance and productivity interactions mediate stability of forest composition and structure.

    PubMed

    O'Connor, Christopher D; Falk, Donald A; Lynch, Ann M; Swetnam, Thomas W; Wilcox, Craig P

    2017-04-01

    Fire is returning to many conifer-dominated forests where species composition and structure have been altered by fire exclusion. Ecological effects of these fires are influenced strongly by the degree of forest change during the fire-free period. Response of fire-adapted species assemblages to extended fire-free intervals is highly variable, even in communities with similar historical fire regimes. This variability in plant community response to fire exclusion is not well understood; however, ecological mechanisms such as individual species' adaptations to disturbance or competition and underlying site characteristics that facilitate or impede establishment and growth have been proposed as potential drivers of assemblage response. We used spatially explicit dendrochronological reconstruction of tree population dynamics and fire regimes to examine the influence of historical disturbance frequency (a proxy for adaptation to disturbance or competition), and potential site productivity (a proxy for underlying site characteristics) on the stability of forest composition and structure along a continuous ecological gradient of pine, dry mixed-conifer, mesic mixed-conifer, and spruce-fir forests following fire exclusion. While average structural density increased in all forests, species composition was relatively stable in the lowest productivity pine-dominated and highest productivity spruce-fir-dominated sites immediately following fire exclusion and for the next 100 years, suggesting site productivity as a primary control on species composition and structure in forests with very different historical fire regimes. Species composition was least stable on intermediate productivity sites dominated by mixed-conifer forests, shifting from primarily fire-adapted species to competition-adapted, fire-sensitive species within 20 years of fire exclusion. Rapid changes to species composition and stand densities have been interpreted by some as evidence of high-severity fire. We

  7. Divergence in Forest-Type Response to Climate and Weather: Evidence for Regional Links Between Forest-Type Evenness and Net Primary Productivity

    USGS Publications Warehouse

    Bradford, J.B.

    2011-01-01

    Climate change is altering long-term climatic conditions and increasing the magnitude of weather fluctuations. Assessing the consequences of these changes for terrestrial ecosystems requires understanding how different vegetation types respond to climate and weather. This study examined 20 years of regional-scale remotely sensed net primary productivity (NPP) in forests of the northern Lake States to identify how the relationship between NPP and climate or weather differ among forest types, and if NPP patterns are influenced by landscape-scale evenness of forest-type abundance. These results underscore the positive relationship between temperature and NPP. Importantly, these results indicate significant differences among broadly defined forest types in response to both climate and weather. Essentially all weather variables that were strongly related to annual NPP displayed significant differences among forest types, suggesting complementarity in response to environmental fluctuations. In addition, this study found that forest-type evenness (within 8 ?? 8 km2 areas) is positively related to long-term NPP mean and negatively related to NPP variability, suggesting that NPP in pixels with greater forest-type evenness is both higher and more stable through time. This is landscape- to subcontinental-scale evidence of a relationship between primary productivity and one measure of biological diversity. These results imply that anthropogenic or natural processes that influence the proportional abundance of forest types within landscapes may influence long-term productivity patterns. ?? 2011 Springer Science+Business Media, LLC (outside the USA).

  8. Quantifying the missing link between albedo and productivity of boreal forests

    NASA Astrophysics Data System (ADS)

    Hovi, Aarne; Liang, Jingjing; Korhonen, Lauri; Kobayashi, Hideki; Rautiainen, Miina

    2016-04-01

    Albedo and fraction of absorbed photosynthetically active radiation (FAPAR) determine the shortwave radiation balance and productivity of forests. Several studies have examined the relation between forest structure and albedo in the boreal zone. Studies regarding FAPAR are fewer and the relations between albedo and FAPAR are still poorly understood. To study these relations we simulated shortwave black sky albedo and canopy FAPAR, using the FRT forest reflectance model. We used two sets of field plots as input data. The plots were located in Alaska, USA (N = 584) and in Finland (N = 506) between Northern latitudes of 60° and 68° , and they represent naturally grown and more intensively managed (regularly thinned) forests, respectively. The simulations were carried out with sun zenith angles (SZA) typical to the biome, ranging from 40° to 80° . The simulated albedos in coniferous plots decreased with increasing tree height, whereas canopy FAPAR showed an opposite trend. The albedo of broadleaved plots was notably higher than that of coniferous plots. No species differences in canopy FAPAR were seen, except for pine forests in Finland that showed lowest FAPAR among species. Albedo and canopy FAPAR were negatively correlated (r ranged from -0.93 to -0.69) in coniferous plots. The correlations were notably weaker (r ranged from -0.64 to 0.05) if plots with broadleaved trees were included. To show the influence of forest management, we further examined the response of albedo and FAPAR to forest density (basal area) and fraction of broadleaved trees. Plots with low basal area showed high albedos but also low canopy FAPAR. When comparing the sparse plots to dense ones, the relative decrease in canopy FAPAR was larger than the relative increase in albedo. However, at large SZAs the basal area could be lowered to approx. 20 m2 ha-1 before FAPAR was notably reduced. Increasing the proportion of broadleaved trees from 0% to 100% increased the albedos to approximately

  9. Revised paradigms of forest production over stand development: Why does carbon storage increase as trees die in aging mixed temperate forests?

    NASA Astrophysics Data System (ADS)

    Gough, C. M.; Curtis, P.; Hardiman, B. S.; Scheuermann, C. M.

    2013-12-01

    The broad emergence of century-old forests in the US upper Midwest and Northeast has large potential implications for carbon (C) storage, as the long-assumed future decline of production in aging stands is expected to reduce continental C sink strength. As mixed temperate forests in the region broadly transition from early to middle stages of succession, short-lived canopy trees are dying and giving way to more structurally complex forests. At the same time, disturbances in the region are shifting from severe events to more moderate disturbances resulting in only partial canopy defoliation. We review new evidence that temperate deciduous forests, against prior expectations, are likely to maintain their capacity to store C over the next several decades even as diffuse mortality of canopy trees increases with advancing age. Forest production data from long-term observational studies and experimental chronosequences in the region do not support a decline in C storage during middle succession. Instead, sustained forest C storage in intermediate-aged forests corresponds with the accrual of structural complexity over time from small-scale, non-stand replacing disturbances such as age-related mortality. Increasing complexity with age gives rise to more efficient use of growth-limiting light and nutrient resources, which may offset, in part or whole, the lost contribution of senescent canopy trees to forest production. These findings indicate that older, structurally complex forests that emerge following diffuse mortality may store C at rates comparable to their younger counterparts. We conclude that regional land-use decisions permitting age-related senescence in maturing forests or, alternatively, management outcomes emulating the structural features of older forests will support goals to maintain the region's C sink strength.

  10. Local and Regional Economic Benefits from Forest Products Production Activities at the Savannah River Site: 1955-Present

    SciTech Connect

    Teeter, L.; Blake, J.I.

    2002-01-01

    SRS was established in 1951 as a nuclear materials production facility; however, decline in the defense mission budget at SRS has created a major economic impact on the community in the Central Savannah River Area. SRS has been offsetting these effects by producing revenue (80 million dollars to date) from the sale of forest products since 1955 primarily trees, but also pine straw. Revenue has been re-invested into the infrastructure development, restoration and management of natural resources. Total asset value of the forest-land has increased from 21 million to over 500 million dollars in the same period.

  11. Hydrogen Production and Delivery Research

    SciTech Connect

    Iouri Balachov, PhD

    2007-10-15

    In response to DOE's Solicitation for Grant Applications DE-PS36-03GO93007, 'Hydrogen Production and Delivery Research', SRI International (SRI) proposed to conduct work under Technical Topic Area 5, Advanced Electrolysis Systems; Sub-Topic 5B, High-Temperature Steam Electrolysis. We proposed to develop a prototype of a modular industrial system for low-cost generation of H{sub 2} (<$2/kg) by steam electrolysis with anodic depolarization by CO. Water will be decomposed electrochemically into H{sub 2} and O{sub 2} on the cathode side of a high-temperature electrolyzer. Oxygen ions will migrate through an oxygen-ion-conductive solid oxide electrolyte. Gas mixtures on the cathode side (H{sub 2} + H{sub 2}O) and on the anode side (CO + CO{sub 2}) will be reliably separated by the solid electrolyte. Depolarization of the anodic process will decrease the electrolysis voltage, and thus the electricity required for H{sub 2} generation and the cost of produced H{sub 2}. The process is expected to be at least 10 times more energy-efficient than low-temperature electrolysis and will generate H{sub 2} at a cost of approximately $1-$1.5/kg. The operating economics of the system can be made even more attractive by deploying it at locations where waste heat is available; using waste heat would reduce the electricity required for heating the system. Two critical targets must be achieved: an H{sub 2} production cost below $2/kg, and scalable design of the pilot H{sub 2} generation system. The project deliverables would be (1) a pilot electrolysis system for H{sub 2} generation, (2) an economic analysis, (3) a market analysis, and (4) recommendations and technical documentation for field deployment. DOE was able to provide only 200K out of 1.8M (or about 10% of awarded budget), so project was stopped abruptly.

  12. Forest products decomposition in municipal solid waste landfills

    SciTech Connect

    Barlaz, Morton A. . E-mail: barlaz@eos.ncsu.edu

    2006-07-01

    Cellulose and hemicellulose are present in paper and wood products and are the dominant biodegradable polymers in municipal waste. While their conversion to methane in landfills is well documented, there is little information on the rate and extent of decomposition of individual waste components, particularly under field conditions. Such information is important for the landfill carbon balance as methane is a greenhouse gas that may be recovered and converted to a CO{sub 2}-neutral source of energy, while non-degraded cellulose and hemicellulose are sequestered. This paper presents a critical review of research on the decomposition of cellulosic wastes in landfills and identifies additional work that is needed to quantify the ultimate extent of decomposition of individual waste components. Cellulose to lignin ratios as low as 0.01-0.02 have been measured for well decomposed refuse, with corresponding lignin concentrations of over 80% due to the depletion of cellulose and resulting enrichment of lignin. Only a few studies have even tried to address the decomposition of specific waste components at field-scale. Long-term controlled field experiments with supporting laboratory work will be required to measure the ultimate extent of decomposition of individual waste components.

  13. Earlier springs decrease peak summer productivity in North American boreal forests

    NASA Astrophysics Data System (ADS)

    Buermann, Wolfgang; Bikash, Parida R.; Jung, Martin; Burn, Donald H.; Reichstein, Markus

    2013-06-01

    In the northern high latitudes, alternative hypotheses with regards to how warming-related shifts in seasonality influence ecosystem productivity exist. Increased plant growth associated with a longer growing season may enhance ecosystem productivity, but shifts to earlier springs may also negatively influence soil moisture status and productivity during the peak of the growing season. Here, we analyzed nearly three decades (1982-2008) of observational records and derived products, including satellite microwave and optical imagery as well as upscaled ecosystem flux observations, to better understand how shifts in seasonality impact hydrology and productivity in the North American boreal forests. We identified a dominant adverse influence of earlier springs on peak summer forest greenness, actual evapotranspiration and productivity at interannual time scales across the drier western and central sections of the North American boreal forests. In the vast regions where this spring onset mechanism operates, ecosystem productivity gains from earlier springs during the early portion of the growing season are effectively cancelled through corresponding losses in the later portion. Our results also indicate that recent decadal shifts towards earlier springs and associated drying in the midst of the growing season over western North American boreal forests may have contributed to the reported declines in summer productivity and increases in tree mortality and fire activity. With projections of accelerated northern high-latitude warming and associated shifts to earlier springs, persistent soil moisture deficits in peak summer may be an effective mechanism for regional-scale boreal forest dieback through their strong influence on productivity, tree mortality and disturbance dynamics.

  14. Phytophthora ramorum: integrative research and management of an emerging pathogen in California and Oregon forests.

    PubMed

    Rizzo, David M; Garbelotto, Matteo; Hansen, Everett M

    2005-01-01

    Phytophthora ramorum, causal agent of sudden oak death, is an emerging plant pathogen first observed in North America associated with mortality of tanoak (Lithocarpus densiflorus) and coast live oak (Quercus agrifolia) in coastal forests of California during the mid-1990s. The pathogen is now known to occur in North America and Europe and have a host range of over 40 plant genera. Sudden oak death has become an example of unintended linkages between the horticultural industry and potential impacts on forest ecosystems. This paper examines the biology and ecology of P. ramorum in California and Oregon forests as well discussing research on the pathogen in a broader management context.

  15. Suggested stocking levels for forest stands in northeastern Oregon and southeastern Washington. Forest Service research note

    SciTech Connect

    Cochran, P.H.; Geist, J.M.; Clemens, D.L.; Clausnitzer, R.R.; Powell, D.C.

    1994-04-01

    Catastrophes and manipulation of stocking levels are primary determinants of stand development and the appearance of future forest landscapes. Managers need stocking level guides particularly for sites incapable of supporting stocking levels presented in normal yield tables. To take advantage of information currently available the authors used some assumptions to relate growth basal area (GBA) to stand density index (SDI) and then create stocking level curves for use in northeastern Oregon and southeastern Washington. Use of these curves cannot be expected to eliminate all insect and disease problems, but the impact of mountain pine beetle should be moderated.

  16. Does species richness affect fine root biomass and production in young forest plantations?

    PubMed

    Domisch, Timo; Finér, Leena; Dawud, Seid Muhie; Vesterdal, Lars; Raulund-Rasmussen, Karsten

    2015-02-01

    Tree species diversity has been reported to increase forest ecosystem above-ground biomass and productivity, but little is known about below-ground biomass and production in diverse mixed forests compared to single-species forests. For testing whether species richness increases below-ground biomass and production and thus complementarity between forest tree species in young stands, we determined fine root biomass and production of trees and ground vegetation in two experimental plantations representing gradients in tree species richness. Additionally, we measured tree fine root length and determined species composition from fine root biomass samples with the near-infrared reflectance spectroscopy method. We did not observe higher biomass or production in mixed stands compared to monocultures. Neither did we observe any differences in tree root length or fine root turnover. One reason for this could be that these stands were still young, and canopy closure had not always taken place, i.e. a situation where above- or below-ground competition did not yet exist. Another reason could be that the rooting traits of the tree species did not differ sufficiently to support niche differentiation. Our results suggested that functional group identity (i.e. conifers vs. broadleaved species) can be more important for below-ground biomass and production than the species richness itself, as conifers seemed to be more competitive in colonising the soil volume, compared to broadleaved species.

  17. Proximity to forest edge does not affect crop production despite pollen limitation.

    PubMed

    Chacoff, Natacha P; Aizen, Marcelo A; Aschero, Valeria

    2008-04-22

    A decline in pollination function has been linked to agriculture expansion and intensification. In northwest Argentina, pollinator visits to grapefruit, a self-compatible but pollinator-dependent crop, decline by approximately 50% at 1km from forest edges. We evaluated whether this decrease in visitation also reduces the pollination service in this crop. We analysed the quantity and quality of pollen deposited on stigmas, and associated limitation of fruit production at increasing distances (edge: 10, 100, 500 and 1000m) from the remnants of Yungas forest. We also examined the quantitative and qualitative efficiency of honeybees as pollen vectors. Pollen receipt and pollen tubes in styles decreased with increasing distance from forest edge; however, this decline did not affect fruit production. Supplementation of natural pollen with self- and cross-pollen revealed that both pollen quantity and quality limited fruit production. Despite pollen limitation, honeybees cannot raise fruit production because they often do not deposit sufficient high-quality pollen per visit to elicit fruit development. However, declines in visitation frequency well below seven visits during a flower's lifespan could decrease production beyond current yields. In this context, the preservation of forest remnants, which act as pollinator sources, could contribute to resilience in crop production. Like wild plants, pollen limitation of the yield among animal-pollinated crops may be common and indicative not only of pollinator scarcity, but also of poor pollination quality, whereby pollinator efficiency, rather than just abundance, can play a broader role than previously appreciated.

  18. [Measurement and estimation methods and research progress of snow evaporation in forests].

    PubMed

    Li, Hui-Dong; Guan, De-Xin; Jin, Chang-Jie; Wang, An-Zhi; Yuan, Feng-Hui; Wu, Jia-Bing

    2013-12-01

    Accurate measurement and estimation of snow evaporation (sublimation) in forests is one of the important issues to the understanding of snow surface energy and water balance, and it is also an essential part of regional hydrological and climate models. This paper summarized the measurement and estimation methods of snow evaporation in forests, and made a comprehensive applicability evaluation, including mass-balance methods (snow water equivalent method, comparative measurements of snowfall and through-snowfall, snow evaporation pan, lysimeter, weighing of cut tree, weighing interception on crown, and gamma-ray attenuation technique) and micrometeorological methods (Bowen-ratio energy-balance method, Penman combination equation, aerodynamics method, surface temperature technique and eddy covariance method). Also this paper reviewed the progress of snow evaporation in different forests and its influencal factors. At last, combining the deficiency of past research, an outlook for snow evaporation rearch in forests was presented, hoping to provide a reference for related research in the future.

  19. Role of MODIS Vegetation Phenology Products in the U.S. for Warn Early Warning System for Forest Threats

    NASA Technical Reports Server (NTRS)

    Spruce, Joseph; Hargrove, William; Norman, Steve; Gasser, Gerald; Smoot, James; Kuper, Philip

    2012-01-01

    U.S. forests occupy approx 751 million acres (approx 1/3 of total land). Several abiotic and biotic damage agents disturb, damage, kill, and/or threaten these forests. Regionally extensive forest disturbances can also threaten human life and property, bio-diversity and water supplies. timely regional forest disturbance monitoring products are needed to aid forest health management work at finer scales. daily MODIS data provide a means to monitor regional forest disturbances on a weekly basis, leveraging vegetation phenology. In response, the USFS and NASA began collaborating in 2006 to develop a Near Real Time (NRT) forest monitoring capability, based on MODIS NDVI data, as part of a national forest threat Early Warning System (EWS).

  20. Analysing Amazonian forest productivity using a new individual and trait-based model (TFS v.1)

    NASA Astrophysics Data System (ADS)

    Fyllas, N. M.; Gloor, E.; Mercado, L. M.; Sitch, S.; Quesada, C. A.; Domingues, T. F.; Galbraith, D. R.; Torre-Lezama, A.; Vilanova, E.; Ramírez-Angulo, H.; Higuchi, N.; Neill, D. A.; Silveira, M.; Ferreira, L.; Aymard C, G. A.; Malhi, Y.; Phillips, O. L.; Lloyd, J.

    2014-02-01

    Repeated long-term censuses have revealed large-scale spatial patterns in Amazon Basin forest structure and dynamism, with some forests in the west of the Basin having up to a twice as high rate of aboveground biomass production and tree recruitment as forests in the east. Possible causes for this variation could be the climatic and edaphic gradients across the Basin and/or the spatial distribution of tree species composition. To help understand causes of this variation a new individual-based model of tropical forest growth designed to take full advantage of the forest census data available from the Amazonian Forest Inventory Network (RAINFOR) has been developed. The model incorporates variations in tree size distribution, functional traits and soil physical properties and runs at the stand level with four functional traits, leaf dry mass per area (Ma), leaf nitrogen (NL) and phosphorus (PL) content and wood density (DW) used to represent a continuum of plant strategies found in tropical forests. We first applied the model to validate canopy-level water fluxes at three Amazon eddy flux sites. For all three sites the canopy-level water fluxes were adequately simulated. We then applied the model at seven plots, where intensive measurements of carbon allocation are available. Tree-by-tree multi-annual growth rates generally agreed well with observations for small trees, but with deviations identified for large trees. At the stand-level, simulations at 40 plots were used to explore the influence of climate and soil fertility on the gross (ΠG) and net (ΠN) primary production rates as well as the carbon use efficiency (CU). Simulated ΠG, ΠN and CU were not associated with temperature. However all three measures of stand level productivity were positively related to annual precipitation and soil fertility.

  1. N{sub 2}O production pathways in the subtropical acid forest soils in China

    SciTech Connect

    Zhang Jinbo; Cai Zucong; Zhu Tongbin

    2011-07-15

    To date, N{sub 2}O production pathways are poorly understood in the humid subtropical and tropical forest soils. A {sup 15}N-tracing experiment was carried out under controlled laboratory conditions to investigate the processes responsible for N{sub 2}O production in four subtropical acid forest soils (pH<4.5) in China. The results showed that denitrification was the main source of N{sub 2}O emission in the subtropical acid forest soils, being responsible for 56.1%, 53.5%, 54.4%, and 55.2% of N{sub 2}O production, in the GC, GS, GB, and TC soils, respectively, under aerobic conditions (40%-52%WFPS). The heterotrophic nitrification (recalcitrant organic N oxidation) accounted for 27.3%-41.8% of N{sub 2}O production, while the contribution of autotrophic nitrification was little in the studied subtropical acid forest soils. The ratios of N{sub 2}O-N emission from total nitrification (heterotrophic+autotrophic nitrification) were higher than those in most previous references. The soil with the lowest pH and highest organic-C content (GB) had the highest ratio (1.63%), suggesting that soil pH-organic matter interactions may exist and affect N{sub 2}O product ratios from nitrification. The ratio of N{sub 2}O-N emission from heterotrophic nitrification varied from 0.02% to 25.4% due to soil pH and organic matter. Results are valuable in the accurate modeling of N2O production in the subtropical acid forest soils and global budget. - Highlights: {yields} We studied N{sub 2}O production pathways in subtropical acid forest soil under aerobic conditions. {yields} Denitrification was the main source of N{sub 2}O production in subtropical acid forest soils. {yields} Heterotrophic nitrification accounted for 27.3%-41.8% of N{sub 2}O production. {yields} While, contribution of autotrophic nitrification to N{sub 2}O production was little. {yields} Ratios of N{sub 2}O-N emission from nitrification were higher than those in most previous references.

  2. The relationship between productivities of salmonids and forest stands in northern California watersheds

    USGS Publications Warehouse

    Frazey, S.L.; Wilzbach, M.A.

    2007-01-01

    Productivities of resident salmonids and upland and riporian forests in 22 small watersheds of coastal northern California were estimated and compared to determine whether: 1) upland site productivity predicted riparian site productivity; 2) either upland or riparian site productivity predicted salmonid productivity; and 3) other parameters explained more of the variance in salmonid productivity. Upland and riparian site productivities were estimated using Site Index values for redwood (Sequoia sempervirens) and red alder (Alnus rubra), respectively. Salmonid productivity was indexed by back-calculated length at age 1 of the largest individuals sampled and by total biomass. Upland and riparian site indices were correlated, but neither factor contributed to the best approximating models of salmonid productivity. Total salmonid biomass was best described by a positive relationship with drainage area. Length of dominant fish was best described by a positive relationship with percentage of hardwoods within riparian areas, which may result from nutrient and/or litter subsidies provided by red older. The inability of forest productivity to predict salmon productivity may reflect insufficient variation in independent variables, limitations of the indices, and the operation of other factors affecting salmonid production. The lack of an apparent relationship between upland conifer and salmonid productivity suggests that management of land for timber productivity and component streams for salmonid production in these sites will require separate, albeit integrated, management strategies.

  3. Enhancement of understory productivity by asynchronous phenology with overstory competitors in a temperate deciduous forest.

    PubMed

    Jolly, William M; Nemani, Ramakrishna; Running, Steven W

    2004-09-01

    Some saplings and shrubs growing in the understory of temperate deciduous forests extend their periods of leaf display beyond that of the overstory, resulting in periods when understory radiation, and hence productivity, are not limited by the overstory canopy. To assess the importance of the duration of leaf display on the productivity of understory and overstory trees of deciduous forests in the north eastern United States, we applied the simulation model, BIOME-BGC with climate data for Hubbard Brook Experimental Forest, New Hampshire, USA and mean ecophysiological data for species of deciduous, temperate forests. Extension of the overstory leaf display period increased overstory leaf area index (LAI) by only 3 to 4% and productivity by only 2 to 4%. In contrast, extending the growing season of the understory relative to the overstory by one week in both spring and fall, increased understory LAI by 35% and productivity by 32%. A 2-week extension of the growing period in both spring and fall increased understory LAI by 53% and productivity by 55%.

  4. Net primary production of a temperate deciduous forest exhibits a threshold response to increasing disturbance severity.

    PubMed

    Stuart-Haëntjens, Ellen J; Curtis, Peter S; Fahey, Robert T; Vogel, Christoph S; Gough, Christopher M

    2015-09-01

    The global carbon (C) balance is vulnerable to disturbances that alter terrestrial C storage. Disturbances to forests occur along a continuum of severity, from low-intensity disturbance causing the mortality or defoliation of only a subset of trees to severe stand- replacing disturbance that kills all trees; yet considerable uncertainty remains in how forest production changes across gradients of disturbance intensity. We used a gradient of tree mortality in an upper Great Lakes forest ecosystem to: (1) quantify how aboveground wood net primary production (ANPP,) responds to a range of disturbance severities; and (2) identify mechanisms supporting ANPPw resistance or resilience following moderate disturbance. We found that ANPPw declined nonlinearly with rising disturbance severity, remaining stable until >60% of the total tree basal area senesced. As upper canopy openness increased from disturbance, greater light availability to the subcanopy enhanced the leaf-level photosynthesis and growth of this formerly light-limited canopy stratum, compensating for upper canopy production losses and a reduction in total leaf area index (LAI). As a result, whole-ecosystem production efficiency (ANPPw/LAI) increased with rising disturbance severity, except in plots beyond the disturbance threshold. These findings provide a mechanistic explanation for a nonlinear relationship between ANPPw, and disturbance severity, in which the physiological and growth enhancement of undisturbed vegetation is proportional to the level of disturbance until a threshold is exceeded. Our results have important ecological and management implications, demonstrating that in some ecosystems moderate levels of disturbance minimally alter forest production.

  5. Maximizing Conservation and Production with Intensive Forest Management: It's All About Location.

    PubMed

    Tittler, Rebecca; Filotas, Élise; Kroese, Jasmin; Messier, Christian

    2015-11-01

    Functional zoning has been suggested as a way to balance the needs of a viable forest industry with those of healthy ecosystems. Under this system, part of the forest is set aside for protected areas, counterbalanced by intensive and extensive management of the rest of the forest. Studies indicate this may provide adequate timber while minimizing road construction and favoring the development of large mature and old stands. However, it is unclear how the spatial arrangement of intensive management areas may affect the success of this zoning. Should these areas be agglomerated or dispersed throughout the forest landscape? Should managers prioritize (a) proximity to existing roads, (b) distance from protected areas, or (c) site-specific productivity? We use a spatially explicit landscape simulation model to examine the effects of different spatial scenarios on landscape structure, connectivity for native forest wildlife, stand diversity, harvest volume, and road construction: (1) random placement of intensive management areas, and (2-8) all possible combinations of rules (a)-(c). Results favor the agglomeration of intensive management areas. For most wildlife species, connectivity was the highest when intensive management was far from the protected areas. This scenario also resulted in relatively high harvest volumes. Maximizing distance of intensive management areas from protected areas may therefore be the best way to maximize the benefits of intensive management areas while minimizing their potentially negative effects on forest structure and biodiversity.

  6. Maximizing Conservation and Production with Intensive Forest Management: It's All About Location

    NASA Astrophysics Data System (ADS)

    Tittler, Rebecca; Filotas, Élise; Kroese, Jasmin; Messier, Christian

    2015-11-01

    Functional zoning has been suggested as a way to balance the needs of a viable forest industry with those of healthy ecosystems. Under this system, part of the forest is set aside for protected areas, counterbalanced by intensive and extensive management of the rest of the forest. Studies indicate this may provide adequate timber while minimizing road construction and favoring the development of large mature and old stands. However, it is unclear how the spatial arrangement of intensive management areas may affect the success of this zoning. Should these areas be agglomerated or dispersed throughout the forest landscape? Should managers prioritize (a) proximity to existing roads, (b) distance from protected areas, or (c) site-specific productivity? We use a spatially explicit landscape simulation model to examine the effects of different spatial scenarios on landscape structure, connectivity for native forest wildlife, stand diversity, harvest volume, and road construction: (1) random placement of intensive management areas, and (2-8) all possible combinations of rules (a)-(c). Results favor the agglomeration of intensive management areas. For most wildlife species, connectivity was the highest when intensive management was far from the protected areas. This scenario also resulted in relatively high harvest volumes. Maximizing distance of intensive management areas from protected areas may therefore be the best way to maximize the benefits of intensive management areas while minimizing their potentially negative effects on forest structure and biodiversity.

  7. Future Forest Production and Net Carbon Sinks under Optimal C:N Balance

    NASA Astrophysics Data System (ADS)

    Makela, A.; Kalliokoski, T.; Peltoniemi, M.

    2014-12-01

    Environmental change affects forests directly by changing physiological process rates, but the consequent changes in resource acquisition may lead to structural and functional acclimations that obscure the long-term relationship between environmental drivers and forest function. Based on an adaptive balance between structure and function, evolutionary optimisation may provide a feasible tool for analysing such indirect effects of environmental change on forests. This study applies OptiPipe, a model of optimal co-allocation of forest carbon (C) and nitrogen (N), to prediction of potential productivity and C balance of Finnish forests under climate change. OptiPipe is embedded in a transparent modular system including: PreLes, a canopy C exchange model; Yasso, a soil C model; and expert assumptions about the impacts of weather on N availability at different growth sites. National Forest Inventory data and gridded weather data (10 x 10 km2) are utilised. The uncertainties of the projections are analysed relative to inputs and parameters. The results quantify the changes in growth and carbon stocks, which are either smaller or larger than those in photosynthetic capacity, depending on the C:N balance of the site. The results emphasize the need to obtain more reliable information and data about nitrogen processes, but also demonstrate the potential for the optimality approach for regional applications.

  8. Life-cycle energy and GHG emissions of forest biomass harvest and transport for biofuel production in Michigan

    DOE PAGES

    Zhang, Fengli; Johnson, Dana M.; Wang, Jinjiang

    2015-04-01

    High dependence on imported oil has increased U.S. strategic vulnerability and prompted more research in the area of renewable energy production. Ethanol production from renewable woody biomass, which could be a substitute for gasoline, has seen increased interest. This study analysed energy use and greenhouse gas emission impacts on the forest biomass supply chain activities within the State of Michigan. A life-cycle assessment of harvesting and transportation stages was completed utilizing peer-reviewed literature. Results for forest-delivered ethanol were compared with those for petroleum gasoline using data specific to the U.S. The analysis from a woody biomass feedstock supply perspective uncoveredmore » that ethanol production is more environmentally friendly (about 62% less greenhouse gas emissions) compared with petroleum based fossil fuel production. Sensitivity analysis was conducted with key inputs associated with harvesting and transportation operations. The results showed that research focused on improving biomass recovery efficiency and truck fuel economy further reduced GHG emissions and energy consumption.« less

  9. Life-cycle energy and GHG emissions of forest biomass harvest and transport for biofuel production in Michigan

    SciTech Connect

    Zhang, Fengli; Johnson, Dana M.; Wang, Jinjiang

    2015-04-01

    High dependence on imported oil has increased U.S. strategic vulnerability and prompted more research in the area of renewable energy production. Ethanol production from renewable woody biomass, which could be a substitute for gasoline, has seen increased interest. This study analysed energy use and greenhouse gas emission impacts on the forest biomass supply chain activities within the State of Michigan. A life-cycle assessment of harvesting and transportation stages was completed utilizing peer-reviewed literature. Results for forest-delivered ethanol were compared with those for petroleum gasoline using data specific to the U.S. The analysis from a woody biomass feedstock supply perspective uncovered that ethanol production is more environmentally friendly (about 62% less greenhouse gas emissions) compared with petroleum based fossil fuel production. Sensitivity analysis was conducted with key inputs associated with harvesting and transportation operations. The results showed that research focused on improving biomass recovery efficiency and truck fuel economy further reduced GHG emissions and energy consumption.

  10. Above- and below-ground net primary productivity across ten Amazonian forests on contrasting soils

    NASA Astrophysics Data System (ADS)

    Aragão, L. E. O. C.; Malhi, Y.; Metcalfe, D. B.; Silva-Espejo, J. E.; Jiménez, E.; Navarrete, D.; Almeida, S.; Costa, A. C. L.; Salinas, N.; Phillips, O. L.; . Anderson, L. O.; Baker, T. R.; Goncalvez, P. H.; Huamán-Ovalle, J.; Mamani-Solórzano, M.; Meir, P.; Monteagudo, A.; Peñuela, M. C.; Prieto, A.; Quesada, C. A.; Rozas-Dávila, A.; Rudas, A.; Silva Junior, J. A.; Vásquez, R.

    2009-02-01

    The net primary productivity (NPP) of tropical forests is one of the most important and least quantified components of the global carbon cycle. Most relevant studies have focused particularly on the quantification of the above-ground coarse wood productivity, and little is known about the carbon fluxes involved in other elements of the NPP, the partitioning of total NPP between its above- and below-ground components and the main environmental drivers of these patterns. In this study we quantify the above- and below-ground NPP of ten Amazonian forests to address two questions: (1) How do Amazonian forests allocate productivity among its above- and below-ground components? (2) How do soil and leaf nutrient status and soil texture affect the productivity of Amazonian forests? Using a standardized methodology to measure the major elements of productivity, we show that NPP varies between 9.3±1.3 Mg C ha-1 yr-1 (mean±standard error), at a white sand plot, and 17.0±1.4 Mg C ha-1 yr-1 at a very fertile Terra Preta site, with an overall average of 12.8±0.9 Mg C ha-1 yr-1. The studied forests allocate on average 64±3% and 36±3% of the total NPP to the above- and below-ground components, respectively. The ratio of above-ground and below-ground NPP is almost invariant with total NPP. Litterfall and fine root production both increase with total NPP, while stem production shows no overall trend. Total NPP tends to increase with soil phosphorus and leaf nitrogen status. However, allocation of NPP to below-ground shows no relationship to soil fertility, but appears to decrease with the increase of soil clay content.

  11. Above- and below-ground net primary productivity across ten Amazonian forests on contrasting soils

    NASA Astrophysics Data System (ADS)

    Aragão, L. E. O. C.; Malhi, Y.; Metcalfe, D. B.; Silva-Espejo, J. E.; Jiménez, E.; Navarrete, D.; Almeida, S.; Costa, A. C. L.; Salinas, N.; Phillips, O. L.; Anderson, L. O.; Alvarez, E.; Baker, T. R.; Goncalvez, P. H.; Huamán-Ovalle, J.; Mamani-Solórzano, M.; Meir, P.; Monteagudo, A.; Patiño, S.; Peñuela, M. C.; Prieto, A.; Quesada, C. A.; Rozas-Dávila, A.; Rudas, A.; Silva, J. A., Jr.; Vásquez, R.

    2009-12-01

    The net primary productivity (NPP) of tropical forests is one of the most important and least quantified components of the global carbon cycle. Most relevant studies have focused particularly on the quantification of the above-ground coarse wood productivity, and little is known about the carbon fluxes involved in other elements of the NPP, the partitioning of total NPP between its above- and below-ground components and the main environmental drivers of these patterns. In this study we quantify the above- and below-ground NPP of ten Amazonian forests to address two questions: (1) How do Amazonian forests allocate productivity among its above- and below-ground components? (2) How do soil and leaf nutrient status and soil texture affect the productivity of Amazonian forests? Using a standardized methodology to measure the major elements of productivity, we show that NPP varies between 9.3±1.3 Mg C ha-1 yr-1 (mean±standard error), at a white sand plot, and 17.0±1.4 Mg C ha-1 yr-1 at a very fertile Terra Preta site, with an overall average of 12.8±0.9 Mg C ha-1 yr-1. The studied forests allocate on average 64±3% and 36±3% of the total NPP to the above- and below-ground components, respectively. The ratio of above-ground and below-ground NPP is almost invariant with total NPP. Litterfall and fine root production both increase with total NPP, while stem production shows no overall trend. Total NPP tends to increase with soil phosphorus and leaf nitrogen status. However, allocation of NPP to below-ground shows no relationship to soil fertility, but appears to decrease with the increase of soil clay content.

  12. Studies in Teaching: 2004 Research Digest. Proceedings of the Annual Research Forum at Wake Forest University (December, 2004)

    ERIC Educational Resources Information Center

    McCoy, Leah P., Ed.

    2005-01-01

    These Proceedings document an educational research forum held at Wake Forest University (Winston-Salem, North Carolina) on December 8, 2004. Table of contents and 26 research studies of high school teaching are included. Studies include: The Use of Authentic Materials in the K-12 French Program (Katherine Elizabeth Baird), Surveying Students: What…

  13. Across a macro-ecological gradient forest competition is strongest at the most productive sites.

    PubMed

    Prior, Lynda D; Bowman, David M J S

    2014-01-01

    We tested the hypothesis that the effect of forest basal area on tree growth interacts with macro-ecological gradients of primary productivity, using a large dataset of eucalypt tree growth collected across temperate and sub- tropical mesic Australia. To do this, we derived an index of inter-tree competition based on stand basal area (stand BA) relative to the climatically determined potential basal area. Using linear mixed effects modeling, we found that the main effects of climatic productivity, tree size, and competition explained 26.5% of the deviance in individual tree growth, but adding interactions to the model could explain a further 8.9%. The effect of competition on growth interacts with the gradient of climatic productivity, with negligible effect of competition in low productivity environments, but marked negative effects at the most productive sites. We also found a positive interaction between tree size and stand BA, which was most pronounced in the most productive sites. We interpret these patterns as reflecting intense competition for light amongst maturing trees on more productive sites, and below ground moisture limitation at low productivity sites, which results in open stands with little competition for light. These trends are consistent with the life history and stand development of eucalypt forests: in cool moist environments, light is the most limiting resource, resulting in size-asymmetric competition, while in hot, low rainfall environments are open forests with little competition for light but where the amount of tree regeneration is limited by water availability.

  14. Satellite Observation of El Nino Effects on Amazon Forest Phenology and Productivity

    NASA Technical Reports Server (NTRS)

    Asner, Gregory P.; Townsend, Alan R.; Braswell, Bobby H.

    2000-01-01

    Climate variability may affect the functioning of Amazon moist tropical forests, and recent modeling analyses suggest that the carbon dynamics of the region vary interannually in response to precipitation and temperature anomalies. However, due to persistent orbital and atmospheric artifacts in the satellite record, remote sensing observations have not provided quantitative evidence that climate variation affects Amazon forest phenology or productivity, We developed a method to minimize and quantify non-biological artifacts in NOAA AVHRR satellite data, providing a record of estimated forest phenological variation from 1982-1993. The seasonal Normalized Difference Vegetation Index (NDVI) amplitude (a proxy for phenology) increased throughout much of the basin during El Nino periods when rainfall was anomalously low. Wetter La Nina episodes brought consistently smaller NDVI amplitudes. Using radiative transfer and terrestrial biogeochemical models driven by these satellite data, we estimate that canopy-energy absorption and net primary production of Amazon forests varied interannually by as much as 21% and 18%, respectively. These results provide large-scale observational evidence for interannual sensitivity to El Nino of plant phenology and carbon flux in Amazon forests.

  15. PREFER: a European service providing forest fire management support products

    NASA Astrophysics Data System (ADS)

    Eftychidis, George; Laneve, Giovanni; Ferrucci, Fabrizio; Sebastian Lopez, Ana; Lourenco, Louciano; Clandillon, Stephen; Tampellini, Lucia; Hirn, Barbara; Diagourtas, Dimitris; Leventakis, George

    2015-06-01

    PREFER is a Copernicus project of the EC-FP7 program which aims developing spatial information products that may support fire prevention and burned areas restoration decisions and establish a relevant web-based regional service for making these products available to fire management stakeholders. The service focuses to the Mediterranean region, where fire risk is high and damages from wildfires are quite important, and develop its products for pilot areas located in Spain, Portugal, Italy, France and Greece. PREFER aims to allow fire managers to have access to online resources, which shall facilitate fire prevention measures, fire hazard and risk assessment, estimation of fire impact and damages caused by wildfire as well as support monitoring of post-fire regeneration and vegetation recovery. It makes use of a variety of products delivered by space borne sensors and develop seasonal and daily products using multi-payload, multi-scale and multi-temporal analysis of EO data. The PREFER Service portfolio consists of two main suite of products. The first refers to mapping products for supporting decisions concerning the Preparedness/Prevention Phase (ISP Service). The service delivers Fuel, Hazard and Fire risk maps for this purpose. Furthermore the PREFER portfolio includes Post-fire vegetation recovery, burn scar maps, damage severity and 3D fire damage assessment products in order to support relative assessments required in context of the Recovery/Reconstruction Phase (ISR Service) of fire management.

  16. In vitro fruiting of `armillaria` species. Forest Service research note

    SciTech Connect

    Reaves, J.L.; McWilliams, M.

    1991-08-01

    Fruiting of Armillaria is sporadic in the interior forests of Western North America, where the most highly pathogenic species of Armillaria occur. If single spores are not available, the species must be determined by haploid/diploid pairings, which may lead to uncertainty over what Armallaria species is present in a particular area. Objectives of this study were to evaluate the feasibility of growing spore-bearing basidiocarps of various Armillaria species in vitro. Spores from these basidiocarps will be used to carry out haploid/diploid pairings.

  17. Will Elevated CO2 Increase Forest Productivity? Evidence from an Australian FACE Experiment

    NASA Astrophysics Data System (ADS)

    Collins, L.

    2015-12-01

    Rising atmospheric CO2 may enhance forest productivity via CO2 fertilisation and increased soil moisture associated with water savings. Quantification of the response of forest productivity to rising CO2 concentrations is important, as increased forest productivity may contribute to the mitigation of anthropogenic climate change. Vegetation greenness indices derived from digital photographs have been correlated with a number of measures of ecosystem productivity including total biomass, leaf area index and gross primary productivity. Our study examines the effect of elevated CO2 on patterns in overstorey and understorey vegetation greenness at a Free Air CO2 Enrichment facility (EucFACE) situated within a temperate eucalypt forest in Sydney, Australia. EucFACE consists of six treatment areas, three subjected to ambient CO2 ('ambient') and three with ambient plus 150 ppm CO2 ('elevated'). Each treatment area had one camera monitoring canopy greenness for a 12 month period and four cameras monitoring one understorey vegetation plot (2.25 m2) each for a 15 month period. Vegetation greenness was measured daily using the green chromatic coordinate (GCC). Understorey and overstorey GCC and rates of understorey greening and browning were not affected by elevated CO2. Periodic differences in canopy greening and browning between CO2 treatments were observed, though these probably reflect an insect defoliation event in one treatment area. Increases in canopy and understorey GCC were associated with a combination of extended periods of high soil volumetric water content (VWC) (>0.1) and high maximum temperatures (>25 °C). Browning appeared to be associated with a combination of periods of high maximum temperatures and low VWC or low minimum temperatures. Our short term findings suggest that eucalypt forest productivity will be sensitive to changes in climate, but may be relatively insensitive to changes in CO2 in the near future.

  18. A Forest Products Technology Program for Washington Community Colleges. Final Report.

    ERIC Educational Resources Information Center

    Grotefend, Robert T.

    This report describes a project to develop a forest product technology curriculum that prepares students at the technical level, junior management, to work in the manufacturing of wood and bark into lumber, plywood, particle board, laminates, and pulp chips. Chapter 1 describes project objectives and procedures followed. In chapter 2 the history…

  19. Skills Conversion Project: Chapter 6, Forest Operations and Wood Products. Final Report.

    ERIC Educational Resources Information Center

    National Society of Professional Engineers, Washington, DC.

    A study of the forest operations and wood products industries was conducted in Atlanta and Seattle by the National Society of Professional Engineers. Included among these industries are tree development, crop and land management, logging, material handling transportation, cutting, peeling, assembly, pulp and paper, mobile homes, construction,…

  20. FOREST HARVESTS AND WOOD PRODUCTS: SOURCES AND SINKS OF ATMOSPHERIC CARBON DIOXIDE

    EPA Science Inventory

    Changes in the net carbon(c)sink-source balance related to a country's forest harvesting and use of wood products is an important component in making country-level inventories of greenhouse gas emissions,a current activity within many signatory nations to the UN Framework Convent...

  1. Post-glacial redistribution and shifts in productivity of giant kelp forests

    PubMed Central

    Graham, Michael H.; Kinlan, Brian P.; Grosberg, Richard K.

    2010-01-01

    Quaternary glacial–interglacial cycles create lasting biogeographic, demographic and genetic effects on ecosystems, yet the ecological effects of ice ages on benthic marine communities are unknown. We analysed long-term datasets to develop a niche-based model of southern Californian giant kelp (Macrocystis pyrifera) forest distribution as a function of oceanography and geomorphology, and synthesized palaeo-oceanographic records to show that late Quaternary climate change probably drove high millennial variability in the distribution and productivity of this foundation species. Our predictions suggest that kelp forest biomass increased up to threefold from the glacial maximum to the mid-Holocene, then rapidly declined by 40–70 per cent to present levels. The peak in kelp forest productivity would have coincided with the earliest coastal archaeological sites in the New World. Similar late Quaternary changes in kelp forest distribution and productivity probably occurred in coastal upwelling systems along active continental margins worldwide, which would have resulted in complex shifts in the relative productivity of terrestrial and marine components of coastal ecosystems. PMID:19846450

  2. 36 CFR 223.241 - Disposal of seized special forest products.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... sale or free use if that product is: (a) Listed or proposed for listing as threatened or endangered under the Endangered Species Act; (b) Identified as prohibited for sale or trade under the Convention on Internal Trade in Endangered Species; or (c) Listed on the Regional Forester's sensitive plant...

  3. [Effect of climate change on net primary productivity of Korean pine (Pinus koraiensis) at different successional stages of broad-leaved Korean pine forest].

    PubMed

    Qiu, Yang; Gao, Lu-Shuang; Zhang, Xue; Guo, Jing; Ma, Zhi-Yuan

    2014-07-01

    Pinus koraiensis in broad-leaved Korean pine forests of Changbai Mountain at different successional stages (secondary poplar-birch forest, secondary coniferous and broad-leaved forest and the primitive Korean pine forest) were selected in this paper as the research objects. In this research, the annual growth of net primary productivity (NPP) (1921-2006) of P. koraiensis was obtained by combining the tree-ring chronology and relative growth formulae, the correlation between NPP of P. koraiensis and climatic factors was developed, and the annual growth of NPP of P. koraiensis at different successional stages in relation to climatic variation within different climate periods were analyzed. The results showed that, in the research period, the correlations between climatic factors and NPP of P. koraiensis at different successional stages were different. With increasing the temperature, the correlations between NPP of P. koraiensis in the secondary poplar-birch forest and the minimum temperatures of previous and current growing seasons changed from being significantly negative to being significantly positive. The positive correlation between NPP of P. koraiensis in the secondary coniferous and broad-leaved forest and the minimum temperature in current spring changed into significantly positive correlation between NPP of P. koraiensis and the temperatures in previous and current growing seasons. The climatic factors had a stronger hysteresis effect on NPP of P. koraiensis in the secondary coniferous and broad-leaved forest, but NPP of P. koraiensis in the primitive Korean pine forest had weaker correlation with temperature but stronger positive correlation with the precipitation of previous growing season. The increases of minimum and mean temperatures were obvious, but no significant variations of the maximum temperature and precipitation were observed at our site. The climatic variation facilitated the increase of the NPP of P. koraiensis in the secondary poplar

  4. Economic Analysis of Planting Forests on Rice Lands in Texas: Sequestering Carbon and Avoiding Methane Production

    NASA Astrophysics Data System (ADS)

    Kronrad, G. D.; Huang, C.

    2005-12-01

    Global climate change is predicted due to increases in greenhouse gasses (i.e. CO2, CH4, CFCs, N2O, O3) in the atmosphere caused by human activities. The atmospheric concentration of methane (CH4), which absorbs and retains heat 21 times more effectively than CO2, has increased. Anaerobic bacterial activity in rice paddies constitutes one of major emission sources of CH4. The rice fields of Texas, for example, accounted for an annual CH4 emission of between 1.1 and 1.6 million tons of CO2 equivalent between 1990 and 2000. Converting marginal rice fields to forests plantations will remove CO2 from the atmosphere, sequester carbon in the forests and prevent the production of CH4. Therefore, carbon credits can be claimed for the carbon sequestered and the avoidance of CH4 production. Analyses were conducted to calculate the amount of carbon sequestered and methane avoided, and the profitability, measured in net present worth (NPW), of managing loblolly pine plantation for 1) timber production only, 2) the dual products of timber products and carbon credits in forests planted on marginal agricultural and unused pastureland and 3) the dual products of timber and carbon storage in forests planted on marginal rice lands. Calculations were performed using three discount rates, three site qualities and five prices for carbon credits. The results indicate that on average quality land, using a discount rate of 8 percent, forests planted on marginal agricultural and unused pastureland earn a NPW of 346 per acre from timber production only; a NPW of 438 per acre from timber and carbon credits (54.4 tons of carbon sequestered), assuming carbon is worth 10 per ton, during one rotation (32 years). The profitability of forest management increases due to the inclusion of carbon credits. The profitability of planting forests on marginal rice fields is even higher, earning a NPW of 566 per acre from timber and carbon credits (54.4 tons of C sequestered and 33.3 tons of C emission

  5. Comparative Research Productivity Measures for Economic Departments.

    ERIC Educational Resources Information Center

    Huettner, David A.; Clark, William

    1997-01-01

    Develops a simple theoretical model to evaluate interdisciplinary differences in research productivity between economics departments and related subjects. Compares the research publishing statistics of economics, finance, psychology, geology, physics, oceanography, chemistry, and geophysics. Considers a number of factors including journal…

  6. Tidal freshwater forested wetlands: Future research needs and an overview of restoration: Chapter 17

    USGS Publications Warehouse

    Conner, William H.; Hackney, Courtney T.; Krauss, Ken W.; Day, John W.

    2007-01-01

    Studies of tidal freshwater forested wetlands are few in contrast to the diversity of conditions and information needs that exist for this ecosystem type. Basic information is lacking on the physiological ecology of major wetland tree species under natural settings, the structure and dynamics of pure and mixed species communities, soil-plant interactions, biogeochemistry, hydrology, soils, wildlife habitat, primary biotic and abiotic functions, and the response of these systems to natural and human-caused disruptions. Existing information is often not in a form that can be applied to ecosystem problems, especially those related to management, restoration, or creation of tidal swamps. Accordingly, there is a critical need for research on fundamental biotic and abiotic processes and functions in tidal forested wetland landscapes on a local and regional scale. In this chapter, we detail those research needs, and we highlight some restoration ideas for tidal freshwater forested wetlands with the hope that much additional research will follow.

  7. A multi-sites analysis on the ozone effects on Gross Primary Production of European forests.

    PubMed

    Proietti, C; Anav, A; De Marco, A; Sicard, P; Vitale, M

    2016-06-15

    Ozone (O3) is both a greenhouse gas and a secondary air pollutant causing adverse impacts on forests ecosystems at different scales, from cellular to ecosystem level. Specifically, the phytotoxic nature of O3 can impair CO2 assimilation that, in turn affects forest productivity. This study aims to evaluate the effects of tropospheric O3 on Gross Primary Production (GPP) at 37 European forest sites during the time period 2000-2010. Due to the lack of carbon assimilation data at O3 monitoring stations (and vice-versa) this study makes a first attempt to combine high resolution MODIS Gross Primary Production (GPP) estimates and O3 measurement data. Partial Correlations, Anomalies Analysis and the Random Forests Analysis (RFA) were used to quantify the effects of tropospheric O3 concentration and its uptake on GPP and to evaluate the most important factors affecting inter-annual GPP changes. Our results showed, along a North-West/South-East European transect, a negative impact of O3 on GPP ranging from 0.4% to 30%, although a key role of meteorological parameters respect to pollutant variables in affecting GPP was found. In particular, meteorological parameters, namely air temperature (T), soil water content (SWC) and relative humidity (RH) are the most important predictors at 81% of test sites. Moreover, it is interesting to highlight a key role of SWC in the Mediterranean areas (Spanish, Italian and French test sites) confirming that, soil moisture and soil water availability affect vegetation growth and photosynthesis especially in arid or semi-arid ecosystems such as the Mediterranean climate regions. Considering the pivotal role of GPP in the global carbon balance and the O3 ability to reduce primary productivity of the forests, this study can help in assessing the O3 impacts on ecosystem services, including wood production and carbon sequestration.

  8. Causes and implications of the correlation between forest productivity and tree mortality rates

    USGS Publications Warehouse

    Stephenson, Nathan L.; van Mantgem, Philip J.; Bunn, Andrew G.; Bruner, Howard; Harmon, Mark E.; O'Connell, Kari B.; Urban, Dean L.; Franklin, Jerry F.

    2011-01-01

    For only one of these four mechanisms, competition, can high mortality rates be considered to be a relatively direct consequence of high NPP. The remaining mechanisms force us to adopt a different view of causality, in which tree growth rates and probability of mortality can vary with at least a degree of independence along productivity gradients. In many cases, rather than being a direct cause of high mortality rates, NPP may remain high in spite of high mortality rates. The independent influence of plant enemies and other factors helps explain why forest biomass can show little correlation, or even negative correlation, with forest NPP.

  9. Student Research: Productive or Counterproductive?

    ERIC Educational Resources Information Center

    McGregor, Joy

    This paper describes two studies conducted with high school students doing library research and writing research papers, with the objective of examining the effectiveness of this type of assignment. The students were all in grade 11, the first group in Canada, the second in the United States. Students were observed in the classroom before they…

  10. Doctoral Preparation and Research Productivity.

    ERIC Educational Resources Information Center

    Farren, Elizabeth A.

    1991-01-01

    According to responses from 76 percent of 200 nurses surveyed, nurses who earn doctorates in any field are likely to go on to conduct nursing research. What seems more important than type of degree is whether the nurses were exposed to computers or participated in faculty research as doctoral students. (Author)

  11. Doctoral preparation and research productivity.

    PubMed

    Farren, E A

    1991-01-01

    According to this study, nurses who earn doctorates in any field are likely to go on to conduct nursing research. What seems more important than type of degree is whether or not the nurses were exposed to computers or participated in faculty research while doctoral students.

  12. Pyrolysis of forest residues: an approach to techno-economics for bio-fuel production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The techno-economics for producing liquid fuels from Maine forest residues were determined from a combination of: (1) laboratory experiments at USDA-ARS’s Eastern Regional Research Center using hog fuel (a secondary woody residue produced from mill byproducts such as sawdust, bark and shavings) as a...

  13. Limitation of Biofuel Production in Europe from the Forest Market

    NASA Astrophysics Data System (ADS)

    Leduc, Sylvain; Wetterlund, Elisabeth; Dotzauer, Erik; Kindermann, Georg

    2013-04-01

    The European Union has set a 10% target for the share of biofuel in the transportation sector to be met by 2020. To reach this target, second generation biofuel is expected to replace 3 to 5% of the transport fossil fuel consumption. But the competition on the feedstock is an issue and makes the planning for the second generation biofuel plant a challenge. Moreover, no commercial second generation biofuel production plant is under operation, but if reaching commercial status, this type of production plants are expected to become very large. In order to minimize the tranportation costs and to takle the competetion for the feedstock against the existing woody based industries, the geographical location of biofuel production plants becomes an issue. This study investigates the potential of second generation biofuel economically feasible in Europe by 2020 in regards with the competition for the feedsstock with the existing woody biomass based industries (CHP, pulp and paper mills, sawmills...). To assess the biofuel potential in Europe, a techno-economic, geographically explicit model, BeWhere, is used. It determines the optimal locations of bio-energy production plants by minimizing the costs and CO2 emissions of the entire supply chain. The existing woody based industries have to first meet their wood demand, and if the amount of wood that remains is suficiant, new bio-energy production plants if any can be set up. Preliminary results show that CHP plants are preferably chosen over biofuel production plants. Strong biofuel policy support is needed in order to consequently increase the biofuel production in Europe. The carbon tax influences the emission reduction to a higher degree than the biofuel support. And the potential of second generation biofuel would at most reach 3% of the European transport fuel if the wood demand does not increase from 2010.

  14. Change of outlook for the forest productivity estimated with remote sensing using the new Collection 6 GPP/NPP MODIS product

    NASA Astrophysics Data System (ADS)

    Marjanović, Hrvoje; Kern, Anikó; Anić, Mislav; Zorana Ostrogović Sever, Maša; Balenović, Ivan; Alberti, Giorgio; Kovač, Goran; Barcza, Zoltán

    2016-04-01

    Estimates of forest productivity from remote sensing data, such as the MOD17 GPP and NPP values derived from MODIS data, are becoming increasingly important tools for monitoring forest productivity in light of the climate change. Hence, small sensor degradation, like the one in the case of MODIS sensor on-board satellite Terra could lead so significant bias in results and false conclusions of the path that the ecosystem is on. In new Collection 6 (C6) of the MOD17 product, the sensor degradation problem has been addressed compared to the previous version Collection 5.5 (C5.5) products, offering a new outlook on the trends in forest productivity. In our work we compared the C5.5 and C6 for MOD17 GPP and NPP products against estimates from eddy covariance and field measurements ('ground truth') at young Pedunculate oak site in Jastrebarsko forest. In order to assess the outlook of forest productivity at larger scale we intersected in GIS maps of forest areas under management and MODIS pixels with 1km spatial resolution. After selecting only those pixels that have at least 90% forest coverage according to the management plans, we analysed the temporal trends and variability in MODIS derived GPP and NPP both from C5.5 and C6 products. Analysis was performed for four main forests classes according to the dominant tree species (Pedunculate oak, Sessile oak, Common beech and Silver fir).

  15. Partial net primary production of a mixed dipterocarp forest: Spatial patterns and temporal dynamics

    NASA Astrophysics Data System (ADS)

    Tan, Zheng-Hong; Deng, Xiao-Bao; Hughes, Alice; Tang, Yong; Cao, Min; Zhang, Wen-Fu; Yang, Xiao-Fei; Sha, Li-Qing; Song, Liang; Zhao, Jun-Fu

    2015-03-01

    We examined how and why partial net primary production (NPPpart) varies across time and space in a Chinese dipterocarp forest. We hypothesize that (1) soil geochemistry explains the spatial pattern of NPPpart within the plot and (2) NPPpart can be used to measure the degree of drought resilience of a natural forest. Spatially, NPPpart was autocorrelated in the range of 75.3 m and homogenous. This spatial pattern could not be well explained by any of the soil properties individually or in combination. If drought sensitivity is defined by marked reduction in NPPpart, the studied forest is drought resilient even when a longer and drier than usual drought hit. Although annual NPPpart was unchanged (vary within 18.24 and 18.52 t ha-1 yr-1) after the drought, the allocation of NPPpart to short-lived litterfall increased, which has further effects on the ecosystem net carbon balance.

  16. Biophysical, morphological, canopy optical property, and productivity data from the Superior National Forest

    NASA Technical Reports Server (NTRS)

    Hall, F. G.; Huemmrich, K. F.; Strebel, D. E.; Goetz, S. J.; Nickeson, J. E.; Woods, K. D.

    1992-01-01

    Described here are the results of a NASA field experiment conducted in the Superior National Forest near Ely, Minnesota, during the summers of 1983 and 1984. The purpose of the experiment was to examine the use of remote sensing to provide measurements of biophysical parameters in the boreal forests. Leaf area index, biomass, net primary productivity, canopy coverage, overstory and understory species composition data are reported for about 60 sites, representing a range of stand density and age for aspen and spruce. Leaf, needle, and bark high-resolution spectral reflectance and transmittance data are reported for the major boreal forest species. Canopy bidirectional reflectance measurements are provided from a helicopter-mounted Barnes Multiband Modular Radiometer (MMR) and the Thematic Mapper Simulator (TMS) on the NASA C-130 aircraft.

  17. Ecohydrology of a semi-arid forest: effects of precipitation pattern and canopy structure on forest productivity

    NASA Astrophysics Data System (ADS)

    Raz Yaseef, N.; Rotenberg, E.; Schiller, G.; Yakir, D.

    2009-12-01

    In dry forest ecosystems water is often the main limitation to carbon sequestration and water availability to the trees is further limited by losses to soil evaporation (E). While it is important to assess E, it is also a difficult variable to directly measure, and can be expected to be highly heterogeneous in open-canopies. We investigated the links between the water and carbon cycles in a semi-arid forest in Southern-Israel (40-year-old P. halepensis forest, with LAI of 1.5 and mean annual precipitation of 285 mm). During a four-year research period we measured precipitation (P, event rain gauges), soil water content (TDRs), evapotranspiration (ET, eddy covariance), tree transpiration (T, sap flux), soil evaporation (E, soil chambers) and intercepted precipitation (calculated). These were combined with on-going measurements of net ecosystem CO2 exchange (NEE), radiation budget and meteorological measurements. On average for the study period, ET accounted for 94% of P, varying between 100% when P<250 mm and 85% when P>300 mm (with indications for losses to subsurface flow and soil moisture storage in wetter years). Both T and E were major fluxes in this dry forest: 45% and 36% of ET, respectively. Two main processes influenced the partitioning of ET between E and T: precipitation patterns and canopy structure. The pulsed-storm pattern, characteristic of semi-arid climates, was sufficient to maintain the topsoil layer wet during the whole wet season (November to March), producing high E during high radiation days (up to 0.70 mm d-1 in the wetting and drying seasons). Only infrequent and relatively intensive storms resulted in infiltration to the depth of maximum rooting density (~25cm) and below, increasing water availability to the trees. As a result, two years with similar P (231 and 224 mm) had different ecosystem water use efficiency: 1.06 (gCO2/kgH2O) in a year with few large storms, but only 0.74 in a year with many small storms. The spatial variability in E

  18. Examining the ecosystem health and sustainability of the world's largest mangrove forest using multi-temporal MODIS products.

    PubMed

    Ishtiaque, Asif; Myint, Soe W; Wang, Chuyuan

    2016-11-01

    Sweeping across Bangladesh and India, the Sundarbans forest is the world's largest contiguous mangrove forest. Although the human population density is high at the edge, Sundarbans has not encountered significant areal transformation in the last four decades. However, we argue that forest degradation can occur discontinuously within the forest without alteration of the entire forest area. In this paper, we used MODIS land products to compare the spatiotemporal ecological dynamics of the Bangladesh and Indian part of this mangrove forest between 2000 and 2010. We used the following 5 ecological parameters for our analysis: the Percent Tree Cover (PTC), Enhanced Vegetation Index (EVI), Net Primary Productivity (NPP), Leaf Area Index (LAI), and Evapotranspiration (ET). Our pixel-based time-series trend analysis for each MODIS image stack, using an ordinary least square (OLS) regression method, showed that forest degradation is happening in fragmented parcels within the forest. The degradation rate is comparatively higher in the Bangladesh part than in the Indian part of Sundarbans. Compartments 8, 10, 12, and 15 in the Bangladesh part, in particular, show high degradation, while compartment 48 and the southern edge of 45 show slight increases in PTC or EVI. Forest degradation in the Indian part of the forest is evident in the National Park and Reserve Forest blocks; however, no substantial degradation is evident in the western section. We have identified certain anthropogenic stressors (i.e., oil pollution, shrimp farming) and natural stressors (i.e., increased salinity, cyclones, forest fire) which might be responsible for the observed degradation. We have provided sustainable planning options and policy transformation alternatives for those areas under pressure from these stressors. We anticipate that our analysis of forest degradation will help management agencies, conservators, and policy makers achieve better management of this world's largest mangrove forest for

  19. Productivity of US Forests: Regional Sensitivity to Variation in Soil Water Availability

    NASA Astrophysics Data System (ADS)

    Nightingale, J. M.; Coops, N. C.; Waring, R. H.

    2006-05-01

    The rates that forests accumulate biomass regionally differ substantially based on the environment and the frequency of disturbance. These dynamics significantly affect the terrestrial carbon balance globally. Since 2000, NASA's Moderate Resolution Imaging Spectro-radiometer (MODIS) has provided 1km spatial resolution estimates of 8-day gross and annual net primary production (GPP and NPP). MODIS productivity is computed as a simple function of absorbed photosynthetically active radiation, and a regionally assigned light-use conversion efficiency that is reduced if temperature or atmospheric vapor pressure deficits are suboptimal. We evaluated the extent that the MODIS productivity estimates might be improved if spatial information on soil water (ASW) storage capacity and soil fertility were available for forested areas across the USA. To accomplish this comparison we parameterized a forest growth model, 3-PGS (Physiological Principles Predicting Growth using Satellite data), which is similar to the MODIS model in operation, but also includes an explicit water balance and a direct link between soil fertility and light-use efficiency. The 3-PGS model was initially run with STATSGO-derived soils information provided by the Oak Ridge National Laboratory. The analysis was expanded to include variation in ASW storage capacity of 50, 100, 200, 300, and 400mm. Annual 3-PGS estimates of NPP for forests across the USA are highly sensitive to limited ASW (<200mm), reducing estimates by up to 60%, as opposed to increasing the ASW capacity (>200mm), which yields an average increase in NPP of 30%. Changing ASW has more influence on forest GPP in the west, where summer drought is prevalent. Generally, productivity estimates from MODIS and 3-PGS were similar across most of the eastern US. However, the MODIS model consistently overestimated mid-summer GPP values in the west because of its insufficient drought constraints.

  20. Wood production response to climate change will depend critically on forest composition and structure.

    PubMed

    Coomes, David A; Flores, Olivier; Holdaway, Robert; Jucker, Tommaso; Lines, Emily R; Vanderwel, Mark C

    2014-12-01

    Established forests currently function as a major carbon sink, sequestering as woody biomass about 26% of global fossil fuel emissions. Whether forests continue to act as a global sink will depend on many factors, including the response of aboveground wood production (AWP; MgC ha(-1 ) yr(-1) ) to climate change. Here, we explore how AWP in New Zealand's natural forests is likely to change. We start by statistically modelling the present-day growth of 97 199 individual trees within 1070 permanently marked inventory plots as a function of tree size, competitive neighbourhood and climate. We then use these growth models to identify the factors that most influence present-day AWP and to predict responses to medium-term climate change under different assumptions. We find that if the composition and structure of New Zealand's forests were to remain unchanged over the next 30 years, then AWP would increase by 6-23%, primarily as a result of physiological responses to warmer temperatures (with no appreciable effect of changing rainfall). However, if warmth-requiring trees were able to migrate into currently cooler areas and if denser canopies were able to form, then a different AWP response is likely: forests growing in the cool mountain environments would show a 30% increase in AWP, while those in the lowland would hardly respond (on average, -3% when mean annual temperature exceeds 8.0 °C). We conclude that response of wood production to anthropogenic climate change is not only dependent on the physiological responses of individual trees, but is highly contingent on whether forests adjust in composition and structure.

  1. Sustaining the Productivity and Function of Intensively Managed Forests - Final Report

    SciTech Connect

    Burger, James A.; Xu, Yi-Jun

    2001-03-23

    The main goal of this study is to ensure sustainable management of wetland forests in the southeastern United States. The study is projected to measure soil, hydrology, and forest responses to several management scenarios across a complete forest cycle. From August 1997 to August 2000 the study has received funding as one of the Agenda 2020 projects, from the U.S. Department of Energy (Cooperative Agreement Number DE-FC07-97ID13551), the National Council of the Paper Industry for Air and Stream Improvement, and Westvac Corporation. Quarterly progress reports were submitted regularly to the Department and all project participants. This final report summarizes the project results and progress achieved during this 3-year period. Over the past three years all research objectives planned for this project were completed.

  2. Using NASA Earth Exchange (NEX) to develop annual US Forest Disturbance products

    NASA Astrophysics Data System (ADS)

    Schleeweis, K.; Huang, C.; Goward, S. N.; Zhao, F. A.; Rishmawi, K.; Dungan, J. L.; Michaelis, A.; Nemani, R. R.; Masek, J. G.; Toney, C.; Moisen, G.; Schroeder, T. A.

    2014-12-01

    The NASA Earth Exchange (NEX) provides a collaborative sharing network allowing users to tap into the NASA Advanced Supercomputing (NAS) Facility and its High-End Computing Capability (HECC). NEX was designed to offer more efficient use of Earth observations for NASA Earth science technology, research and applications. Using the NEX computing environment, the North American Forest Dynamics (NAFD) Project was efficiently able to process 150,000 Landsat images (L5-L7), creating estimates and annual maps of forest cover change and reducing uncertainty in the spatial and temporal dynamics of forest change for the CONUS (1985 -2010). To accomplish this goal, NAFD project demands included Landsat image assessment and selection, pre-processing, algorithm improvement, change analysis, map quality assessment and post-processing. NEX's large computing resources were integral for NAFD research on Biomass modeling and empirical modeling for attribution of forest change agents across the CONUS. In this presentation we describe NAFD research and findings in the context of the NEX platform that made it possible.

  3. Fiber optic gyros from research to production

    NASA Astrophysics Data System (ADS)

    Pavlath, George A.

    2016-05-01

    Fiber optic gyros are a great success story for a new inertial measurement technology that successfully transitioned from the laboratory in 1975 to production in 1992. This paper will review their research, advanced development, product development, and production transfer. The focus of the paper will be this cycle from Stanford University to Northrop Grumman.

  4. Tropical forest conservation and development: A bibliography. Manual No. 1

    SciTech Connect

    Albrecht, J.

    1993-01-01

    Contents: forest resources; deforestation; conservation and sustainable development; indigenous peoples; management, policy, and planning; trade and industrial development; nontimber forest products; research, education, and training; history; bibliographies and general works; author index.

  5. Research Using ASDC Data Products

    Atmospheric Science Data Center

    2013-04-18

    ... use with PICASSO-CENA lidar data," (PDF 4MB) Stuart A. Young, C.S.I.R.O. Atmospheric Research, Aspendale, VIC, Australia. ... data sets initially created for CERES SARB validation (Dr. Thomas Charlock, Lead Scientist) CERES/ARM/GEWEX Experiment (CAGEX) ...

  6. Benefits of hydrogen production research

    NASA Technical Reports Server (NTRS)

    Manvi, R.; Fujita, T.; Rossen, W.; Jacobs, C.

    1976-01-01

    An economic analysis of total monetary benefits arising from increased volume and efficiency of hydrogen production from various primary energy sources is carried out. The analysis is based on NASA's projections of future hydrogen demand in terms of both established industrial-chemical uses and new energy system applications, along with the mix of primary energy sources needed to meet this demand. A cost methodology model is worked out with the basic cost elements being plant construction costs, feedstock and energy costs, and operating and labor-related costs. A computer simulation technique was developed and a set of model calculations was performed. Some representative outputs of the computer analysis are displayed and conclusions are drawn on major factors determining the overall savings possible in hydrogen production and on its technological and economic impact.

  7. Variations in Amazon forest productivity correlated with foliar nutrients and modelled rates of photosynthetic carbon supply.

    PubMed

    Mercado, Lina M; Patiño, Sandra; Domingues, Tomas F; Fyllas, Nikolaos M; Weedon, Graham P; Sitch, Stephen; Quesada, Carlos Alberto; Phillips, Oliver L; Aragão, Luiz E O C; Malhi, Yadvinder; Dolman, A J; Restrepo-Coupe, Natalia; Saleska, Scott R; Baker, Timothy R; Almeida, Samuel; Higuchi, Niro; Lloyd, Jon

    2011-11-27

    The rate of above-ground woody biomass production, W(P), in some western Amazon forests exceeds those in the east by a factor of 2 or more. Underlying causes may include climate, soil nutrient limitations and species composition. In this modelling paper, we explore the implications of allowing key nutrients such as N and P to constrain the photosynthesis of Amazon forests, and also we examine the relationship between modelled rates of photosynthesis and the observed gradients in W(P). We use a model with current understanding of the underpinning biochemical processes as affected by nutrient availability to assess: (i) the degree to which observed spatial variations in foliar [N] and [P] across Amazonia affect stand-level photosynthesis; and (ii) how these variations in forest photosynthetic carbon acquisition relate to the observed geographical patterns of stem growth across the Amazon Basin. We find nutrient availability to exert a strong effect on photosynthetic carbon gain across the Basin and to be a likely important contributor to the observed gradient in W(P). Phosphorus emerges as more important than nitrogen in accounting for the observed variations in productivity. Implications of these findings are discussed in the context of future tropical forests under a changing climate.

  8. Status of the Southern Carpathian forests in the long-term ecological research network.

    PubMed

    Badea, Ovidiu; Bytnerowicz, Andrzej; Silaghi, Diana; Neagu, Stefan; Barbu, Ion; Iacoban, Carmen; Iacob, Corneliu; Guiman, Gheorghe; Preda, Elena; Seceleanu, Ioan; Oneata, Marian; Dumitru, Ion; Huber, Viorela; Iuncu, Horia; Dinca, Lucian; Leca, Stefan; Taut, Ioan

    2012-12-01

    Air pollution, bulk precipitation, throughfall, soil condition, foliar nutrients, as well as forest health and growth were studied in 2006-2009 in a long-term ecological research (LTER) network in the Bucegi Mountains, Romania. Ozone (O(3)) was high indicating a potential for phytotoxicity. Ammonia (NH(3)) concentrations rose to levels that could contribute to deposition of nutritional nitrogen (N) and could affect biodiversity changes. Higher that 50% contribution of acidic rain (pH < 5.5) contributed to increased acidity of forest soils. Foliar N concentrations for Norway spruce (Picea abies), Silver fir (Abies alba), Scots pine (Pinus sylvestris), and European beech (Fagus sylvatica) were normal, phosphorus (P) was high, while those of potassium (K), magnesium (Mg), and especially of manganese (Mn) were significantly below the typical European or Carpathian region levels. The observed nutritional imbalance could have negative effects on forest trees. Health of forests was moderately affected, with damaged trees (crown defoliation >25%) higher than 30%. The observed crown damage was accompanied by the annual volume losses for the entire research forest area up to 25.4%. High diversity and evenness specific to the stand type's structures and local climate conditions were observed within the herbaceous layer, indicating that biodiversity of the vascular plant communities was not compromised.

  9. Do species traits determine patterns of wood production in Amazonian forests?

    NASA Astrophysics Data System (ADS)

    Baker, T. R.; Phillips, O. L.; Laurance, W. F.; Pitman, N. C. A.; Almeida, S.; Arroyo, L.; Difiore, A.; Erwin, T.; Higuchi, N.; Killeen, T. J.; Laurance, S. G.; Nascimento, H.; Monteagudo, A.; Neill, D. A.; Silva, J. N. M.; Malhi, Y.; López Gonzalez, G.; Peacock, J.; Quesada, C. A.; Lewis, S. L.; Lloyd, J.

    2009-02-01

    Understanding the relationships between plant traits and ecosystem properties at large spatial scales is important for predicting how compositional change will affect carbon cycling in tropical forests. In this study, we examine the relationships between species wood density, maximum height and above-ground, coarse wood production of trees ≥10 cm diameter (CWP) for 60 Amazonian forest plots. Average species maximum height and wood density are lower in Western than Eastern Amazonia and are negatively correlated with CWP. To test the hypothesis that variation in these traits causes the variation in CWP, we generate plot-level estimates of CWP by resampling the full distribution of tree biomass growth rates whilst maintaining the appropriate tree-diameter and functional-trait distributions for each plot. These estimates are then compared with the observed values. Overall, the estimates do not predict the observed, regional-scale pattern of CWP, suggesting that the variation in community-level trait values does not determine variation in coarse wood productivity in Amazonian forests. Instead, the regional gradient in CWP is caused by higher biomass growth rates across all tree types in Western Amazonia. Therefore, the regional gradient in CWP is driven primarily by environmental factors, rather than the particular functional composition of each stand. These results contrast with previous findings for forest biomass, where variation in wood density, associated with variation in species composition, is an important driver of regional-scale patterns in above-ground biomass. Therefore, in tropical forests, above-ground wood productivity may be less sensitive than biomass to compositional change that alters community-level averages of these plant traits.

  10. Landscape and plant physiological controls on water dynamics and forest productivity within a watershed

    NASA Astrophysics Data System (ADS)

    Hu, Jia; Jencso, Kelsey; Looker, Nathaniel; Martin, Justin; Hoylman, Zachary

    2015-04-01

    Across the Western U.S., declining snowpacks have resulted in increased water limitation, leading to reduced productivity in high elevation forests. While our current understanding of how forests respond to climate change is typically focused on measuring/modeling the physiological responses and climate feedbacks, our study aims to combine physiology with hydrology to examine how landscape topography modulates the sensitivity of forests to climate. In a forested watershed in Western Montana, we linked climate variability to the physical watershed characteristics and the physiological response of vegetation to examine forest transpiration and productivity rates. Across the entire watershed, we found a strong relationship between productivity and the topographic wetness index, a proxy for soil moisture storage. However, this relationship was highly dependent on the intensity of solar radiation, suggesting that at high elevations productivity was limited by temperature, while at low elevations productivity was limited by moisture. In order to identify the mechanisms responsible for this relationship, we then examined how different coniferous species respond to changing environmental and hydrologic regimes. We first examined transpiration and productivity rates at the hillslope scale at four plots, ranging in elevation and aspect across the watershed. We found trees growing in the hollows had higher transpiration and productivity rates than trees growing in the side slope, but that these differences were more pronounced at lower elevations. We then used oxygen isotope to examine water source use by different species across the watershed. We found that trees growing in the hollows used snowmelt for a longer period. This was most likely due to upslope subsidies of snowmelt water to the hollow areas. However, we found that trees growing at lower elevations used proportionally more snowmelt than trees at the higher elevations. This was most likely due to the trees at lower

  11. Overview of North American stored product research

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Major locations for stored product research in North America are in Winnipeg, Manitoba, Canada, and Manhattan, Kansas, USA. Recent personnel changes and research areas are reviewed. One of the pressing research areas in the U.S. is reducing the need for fumigations in flour mills and evaluating alte...

  12. Ground-Based Lidar Measurements of Forest Canopy Structure as Predictors of Net Primary Production Across Successional Time

    NASA Astrophysics Data System (ADS)

    Scheuermann, C. M.; Gough, C. M.; Nave, L. E.

    2015-12-01

    Forest canopy structure is a key predictor of gas exchange processes that control carbon (C) uptake, including the allocation of photosynthetically fixed C to new plant biomass growth, or net primary production (NPP). Prior work suggests forest canopy structural complexity (CSC), the arrangement of leaves within a volume of canopy, changes as forests develop and is a strong predictor of NPP. However, the expressions of CSC that best predict NPP over decadal to century timescales is unknown. Our objectives were to use multiple remote sensing observations to characterize forest canopy structure in increasing dimensional complexity over a forest age gradient, and to identify which expressions of physical structure best served as proxies of NPP. The study at the University of Michigan Biological Station in Pellston, MI, USA uses two parallel forest chronosequences with different harvesting and fire disturbance histories and includes three old-growth ecosystems varying in canopy composition. We have derived several expressions of 2-D and 3-D forest canopy structure from hemispherical images, a ground-based portable canopy lidar (PCL), and a 3-D terrestrial lidar scanner (TLS), and are relating these structural metrics with NPP and light and nitrogen allocation within the canopy. Preliminary analysis shows that old-growth stands converged on a common mean CSC, but with substantially higher within-stand variation in complexity as deciduous tree species increased in forest canopy dominance. Forest stands that were more intensely disturbed were slower to recover leaf area index (LAI) as they regrew, but 2-D measures of CSC increased similarly as forests aged, regardless of disturbance history. Ongoing work will relate long-term trends in forest CSC with NPP and resource allocation to determine which forest structure remote sensing products are most useful for modeling and scaling C cycling processes through different stages of forest development.

  13. On the relationships between leaf-litter lignin and net primary productivity in tropical rain forests.

    PubMed

    Kitayama, Kanehiro; Suzuki, Shizuo; Hori, Masato; Takyu, Masaaki; Aiba, Shin-Ichiro; Majalap-Lee, Noreen; Kikuzawa, Kihachiro

    2004-07-01

    We investigated if tropical rainforest trees produced more-lignified leaves in less productive environments using forests on Mount Kinabalu, Borneo. Our investigation was based on two earlier suggestions that slower litter decomposition occurs under less productive forests and that trees under resource limitation invest a large amount of carbon as lignin as a defense substance to minimize the loss from herbivores. When nine forests at different altitudes (700-3100 m) and soil conditions (derived from sedimentary or ultrabasic rocks) but with the same gentle relief position were compared, the concentrations of leaf-litter lignin were positively correlated with litterfall rates and leaf-litter nitrogen concentrations. These patterns would be reinforced in intact leaves if the effects of resorption at the time of leaf shedding were taken into account, because greater magnitude of resorption of mobile elements but not of lignin would occur in less productive environments (i.e. dilution of lignin in intact leaves). These results did not support earlier suggestions to explain the variation of leaf-litter lignin. Instead, we suggest that lower lignin contents are adaptive to recycle minerals without retarding decomposition in less productive environments.

  14. Analysing Amazonian forest productivity using a new individual and trait-based model (TFS v.1)

    NASA Astrophysics Data System (ADS)

    Fyllas, N. M.; Gloor, E.; Mercado, L. M.; Sitch, S.; Quesada, C. A.; Domingues, T. F.; Galbraith, D. R.; Torre-Lezama, A.; Vilanova, E.; Ramírez-Angulo, H.; Higuchi, N.; Neill, D. A.; Silveira, M.; Ferreira, L.; Aymard C., G. A.; Malhi, Y.; Phillips, O. L.; Lloyd, J.

    2014-07-01

    Repeated long-term censuses have revealed large-scale spatial patterns in Amazon basin forest structure and dynamism, with some forests in the west of the basin having up to a twice as high rate of aboveground biomass production and tree recruitment as forests in the east. Possible causes for this variation could be the climatic and edaphic gradients across the basin and/or the spatial distribution of tree species composition. To help understand causes of this variation a new individual-based model of tropical forest growth, designed to take full advantage of the forest census data available from the Amazonian Forest Inventory Network (RAINFOR), has been developed. The model allows for within-stand variations in tree size distribution and key functional traits and between-stand differences in climate and soil physical and chemical properties. It runs at the stand level with four functional traits - leaf dry mass per area (Ma), leaf nitrogen (NL) and phosphorus (PL) content and wood density (DW) varying from tree to tree - in a way that replicates the observed continua found within each stand. We first applied the model to validate canopy-level water fluxes at three eddy covariance flux measurement sites. For all three sites the canopy-level water fluxes were adequately simulated. We then applied the model at seven plots, where intensive measurements of carbon allocation are available. Tree-by-tree multi-annual growth rates generally agreed well with observations for small trees, but with deviations identified for larger trees. At the stand level, simulations at 40 plots were used to explore the influence of climate and soil nutrient availability on the gross (ΠG) and net (ΠN) primary production rates as well as the carbon use efficiency (CU). Simulated ΠG, ΠN and CU were not associated with temperature. On the other hand, all three measures of stand level productivity were positively related to both mean annual precipitation and soil nutrient status

  15. A heat wave during leaf expansion severely reduces productivity and modifies seasonal growth patterns in a northern hardwood forest.

    PubMed

    Stangler, Dominik Florian; Hamann, Andreas; Kahle, Hans-Peter; Spiecker, Heinrich

    2016-10-13

    A useful approach to monitor tree response to climate change and environmental extremes is the recording of long-term time series of stem radial variations obtained with precision dendrometers. Here, we study the impact of environmental stress on seasonal growth dynamics and productivity of yellow birch (Betula alleghaniensis Britton) and sugar maple (Acer saccharum Marsh.) in the Great Lakes, St Lawrence forest region of Ontario. Specifically, we research the effects of a spring heat wave in 2010, and a summer drought in 2012 that occurred during the 2005-14 study period. We evaluated both growth phenology (onset, cessation, duration of radial growth, time of maximum daily growth rate) and productivity (monthly and seasonal average growth rates, maximum daily growth rate, tree-ring width) and tested for differences and interactions among species and years. Productivity of sugar maple was drastically compromised by a 3-day spring heat wave in 2010 as indicated by low growth rates, very early growth cessation and a lagged growth onset in the following year. Sugar maple also responded more sensitively than yellow birch to a prolonged drought period in July 2012, but final tree-ring width was not significantly reduced due to positive responses to above-average temperatures in the preceding spring. We conclude that sugar maple, a species that currently dominates northern hardwood forests, is vulnerable to heat wave disturbances during leaf expansion, which might occur more frequently under anticipated climate change.

  16. 25 CFR 163.30 - Revocable road use and construction permits for removal of commercial forest products.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 25 Indians 1 2012-04-01 2011-04-01 true Revocable road use and construction permits for removal of commercial forest products. 163.30 Section 163.30 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER GENERAL FORESTRY REGULATIONS Forest Management and Operations § 163.30...

  17. 25 CFR 163.30 - Revocable road use and construction permits for removal of commercial forest products.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false Revocable road use and construction permits for removal of commercial forest products. 163.30 Section 163.30 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER GENERAL FORESTRY REGULATIONS Forest Management and Operations §...

  18. 25 CFR 163.30 - Revocable road use and construction permits for removal of commercial forest products.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 25 Indians 1 2011-04-01 2011-04-01 false Revocable road use and construction permits for removal of commercial forest products. 163.30 Section 163.30 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER GENERAL FORESTRY REGULATIONS Forest Management and Operations §...

  19. 25 CFR 163.30 - Revocable road use and construction permits for removal of commercial forest products.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 25 Indians 1 2014-04-01 2014-04-01 false Revocable road use and construction permits for removal of commercial forest products. 163.30 Section 163.30 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER GENERAL FORESTRY REGULATIONS Forest Management and Operations §...

  20. 25 CFR 163.30 - Revocable road use and construction permits for removal of commercial forest products.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 25 Indians 1 2013-04-01 2013-04-01 false Revocable road use and construction permits for removal of commercial forest products. 163.30 Section 163.30 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER GENERAL FORESTRY REGULATIONS Forest Management and Operations §...

  1. Litter production and litter elemental composition in two rehabilitated Kandelia obovata mangrove forests in Jiulongjiang Estuary, China.

    PubMed

    Ye, Y; Chen, Y P; Chen, G C

    2013-02-01

    Spatial and seasonal variations in litter production and C, N, and P concentrations were compared between the 24 and 48 year old Kandelia obovata mangrove forests in the Jiulongjiang estuary, China. The 24 yr forest had significantly higher production of total, leaf and branch litter, but lower flower and fruit litter than the 48 yr forest. Total, leaf and branch litter production were significantly positively correlated to monthly temperature and rainfall. Spatial patterns of litter production among the inner, mid and outer zones in the same forest were similar to those of tree heights. C, N and P concentrations of leaf litter showed significant seasonality but varied little among these three forest zones. C/N and N/P ratios of leaf litter were significantly lower for the 24 yr forest than those for the 48 yr forest. During the entire sampling year, total litter of the 24 and 48 yr forests contained 590.31 and 437.31 g C m(-2) yr(-1), 8.46 and 5.47 g N m(-2) yr(-1), 1.92 and 1.16 g P m(-2) yr(-1), respectively.

  2. Operationalizing measurement of forest degradation: Identification and quantification of charcoal production in tropical dry forests using very high resolution satellite imagery

    NASA Astrophysics Data System (ADS)

    Dons, K.; Smith-Hall, C.; Meilby, H.; Fensholt, R.

    2015-07-01

    Quantification of forest degradation in monitoring and reporting as well as in historic baselines is among the most challenging tasks in national REDD+ strategies. However, a recently introduced option is to base monitoring systems on subnational conditions such as prevalent degradation activities. In Tanzania, charcoal production is considered a major cause of forest degradation, but is challenging to quantify due to sub-canopy biomass loss, remote production sites and illegal trade. We studied two charcoal production sites in dry Miombo woodland representing open woodland conditions near human settlements and remote forest with nearly closed canopies. Supervised classification and adaptive thresholding were applied on a pansharpened QuickBird (QB) image to detect kiln burn marks (KBMs). Supervised classification showed reasonable detection accuracy in the remote forest site only, while adaptive thresholding was found acceptable at both locations. We used supervised classification and manual digitizing for KBM delineation and found acceptable delineation accuracy at both sites with RMSEs of 25-32% compared to ground measurements. Regression of charcoal production on KBM area delineated from QB resulted in R2s of 0.86-0.88 with cross-validation RMSE ranging from 2.22 to 2.29 Mg charcoal per kiln. This study demonstrates, how locally calibrated remote sensing techniques may be used to identify and delineate charcoal production sites for estimation of charcoal production and associated extraction of woody biomass.

  3. Economic feasibility of products from inland west small-diameter timber. Forest Service general technical report

    SciTech Connect

    Spelter, H.; Wang, R.; Ince, P.

    1996-05-01

    A large part of the forests located in the Rocky Mountain region of the U.S. West (inland West) is characterized by densely packed, small-diameter stands. The purpose of this study was to examine the economic feasibility of using small-diameter material from this resource to manufacture various wood products: oriented strandboard (OSB), stud lumber, random-length dimension lumber, machine-stress-rated random-length lumber, laminated veneer lumber (LVL), and market pulp.

  4. Nitrogen decreases and precipitation increases ectomycorrhizal extramatrical mycelia production in a longleaf pine forest.

    PubMed

    Sims, Stephanie E; Hendricks, Joseph J; Mitchell, Robert J; Kuehn, Kevin A; Pecot, Stephen D

    2007-06-01

    The rates and controls of ectomycorrhizal fungal production were assessed in a 22-year-old longleaf pine (Pinus palustris Mill.) plantation using a complete factorial design that included two foliar scorching (control and 95% plus needle scorch) and two nitrogen (N) fertilization (control and 5 g N m(-2) year(-1)) treatments during an annual assessment. Ectomycorrhizal fungi production comprised of extramatrical mycelia, Hartig nets and mantles on fine root tips, and sporocarps was estimated to be 49 g m(-2) year(-1) in the control treatment plots. Extramatrical mycelia accounted for approximately 95% of the total mycorrhizal production estimate. Mycorrhizal production rates did not vary significantly among sample periods throughout the annual assessment (p = 0.1366). In addition, reduction in foliar leaf area via experimental scorching treatments did not influence mycorrhizal production (p = 0.9374), suggesting that stored carbon (C) may decouple the linkage between current photosynthate production and ectomycorrhizal fungi dynamics in this forest type. Nitrogen fertilization had a negative effect, whereas precipitation had a positive effect on mycorrhizal fungi production (p = 0.0292; r (2) = 0.42). These results support the widely speculated but poorly documented supposition that mycorrhizal fungi are a large and dynamic component of C flow and nutrient cycling dynamics in forest ecosystems.

  5. Net primary productivity of forest stands in New Hampshire estimated from Landsat and MODIS satellite data

    PubMed Central

    Potter, Christopher; Gross, Peggy; Genovese, Vanessa; Smith, Marie-Louise

    2007-01-01

    Background A simulation model that relies on satellite observations of vegetation cover from the Landsat 7 sensor and from the Moderate Resolution Imaging Spectroradiometer (MODIS) was used to estimate net primary productivity (NPP) of forest stands at the Bartlett Experiment Forest (BEF) in the White Mountains of New Hampshire. Results Net primary production (NPP) predicted from the NASA-CASA model using 30-meter resolution Landsat inputs showed variations related to both vegetation cover type and elevational effects on mean air temperatures. Overall, the highest predicted NPP from the NASA-CASA model was for deciduous forest cover at low to mid-elevation locations over the landscape. Comparison of the model-predicted annual NPP to the plot-estimated values showed a significant correlation of R2 = 0.5. Stepwise addition of 30-meter resolution elevation data values explained no more than 20% of the residual variation in measured NPP patterns at BEF. Both the Landsat 7 and the 250-meter resolution MODIS derived mean annual NPP predictions for the BEF plot locations were within ± 2.5% of the mean of plot estimates for annual NPP. Conclusion Although MODIS imagery cannot capture the spatial details of NPP across the network of closely spaced plot locations as well as Landsat, the MODIS satellite data as inputs to the NASA-CASA model does accurately predict the average annual productivity of a site like the BEF. PMID:17941989

  6. Tree Productivity Enhanced with Conversion from Forest to Urban Land Covers.

    PubMed

    Briber, Brittain M; Hutyra, Lucy R; Reinmann, Andrew B; Raciti, Steve M; Dearborn, Victoria K; Holden, Christopher E; Dunn, Allison L

    2015-01-01

    Urban areas are expanding, changing the structure and productivity of landscapes. While some urban areas have been shown to hold substantial biomass, the productivity of these systems is largely unknown. We assessed how conversion from forest to urban land uses affected both biomass structure and productivity across eastern Massachusetts. We found that urban land uses held less than half the biomass of adjacent forest expanses with a plot level mean biomass density of 33.5 ± 8.0 Mg C ha(-1). As the intensity of urban development increased, the canopy cover, stem density, and biomass decreased. Analysis of Quercus rubra tree cores showed that tree-level basal area increment nearly doubled following development, increasing from 17.1 ± 3.0 to 35.8 ± 4.7 cm(2) yr(-1). Scaling the observed stem densities and growth rates within developed areas suggests an aboveground biomass growth rate of 1.8 ± 0.4 Mg C ha(-1) yr(-1), a growth rate comparable to nearby, intact forests. The contrasting high growth rates and lower biomass pools within urban areas suggest a highly dynamic ecosystem with rapid turnover. As global urban extent continues to grow, cities consider climate mitigation options, and as the verification of net greenhouse gas emissions emerges as critical for policy, quantifying the role of urban vegetation in regional-to-global carbon budgets will become ever more important.

  7. Tree Productivity Enhanced with Conversion from Forest to Urban Land Covers

    PubMed Central

    Briber, Brittain M.; Hutyra, Lucy R.; Reinmann, Andrew B.; Raciti, Steve M.; Dearborn, Victoria K.; Holden, Christopher E.; Dunn, Allison L.

    2015-01-01

    Urban areas are expanding, changing the structure and productivity of landscapes. While some urban areas have been shown to hold substantial biomass, the productivity of these systems is largely unknown. We assessed how conversion from forest to urban land uses affected both biomass structure and productivity across eastern Massachusetts. We found that urban land uses held less than half the biomass of adjacent forest expanses with a plot level mean biomass density of 33.5 ± 8.0 Mg C ha-1. As the intensity of urban development increased, the canopy cover, stem density, and biomass decreased. Analysis of Quercus rubra tree cores showed that tree-level basal area increment nearly doubled following development, increasing from 17.1 ± 3.0 to 35.8 ± 4.7 cm2 yr-1. Scaling the observed stem densities and growth rates within developed areas suggests an aboveground biomass growth rate of 1.8 ± 0.4 Mg C ha-1 yr-1, a growth rate comparable to nearby, intact forests. The contrasting high growth rates and lower biomass pools within urban areas suggest a highly dynamic ecosystem with rapid turnover. As global urban extent continues to grow, cities consider climate mitigation options, and as the verification of net greenhouse gas emissions emerges as critical for policy, quantifying the role of urban vegetation in regional-to-global carbon budgets will become ever more important. PMID:26302444

  8. Time management strategies for research productivity.

    PubMed

    Chase, Jo-Ana D; Topp, Robert; Smith, Carol E; Cohen, Marlene Z; Fahrenwald, Nancy; Zerwic, Julie J; Benefield, Lazelle E; Anderson, Cindy M; Conn, Vicki S

    2013-02-01

    Researchers function in a complex environment and carry multiple role responsibilities. This environment is prone to various distractions that can derail productivity and decrease efficiency. Effective time management allows researchers to maintain focus on their work, contributing to research productivity. Thus, improving time management skills is essential to developing and sustaining a successful program of research. This article presents time management strategies addressing behaviors surrounding time assessment, planning, and monitoring. Herein, the Western Journal of Nursing Research editorial board recommends strategies to enhance time management, including setting realistic goals, prioritizing, and optimizing planning. Involving a team, problem-solving barriers, and early management of potential distractions can facilitate maintaining focus on a research program. Continually evaluating the effectiveness of time management strategies allows researchers to identify areas of improvement and recognize progress.

  9. Nuclear DNA content affects the productivity of conifer forests by altering hydraulic architecture

    NASA Astrophysics Data System (ADS)

    Alday, Josu; Resco de Dios, Víctor

    2014-05-01

    Predictions of future global climate rely on feedbacks between terrestrial vegetation and the global carbon cycle, but the exact mechanisms underlying this relationship are still being discussed. One of the key knowledge gaps lies on the scaling of cellular processes to the ecosystem level. Here we examine whether an under-explored plant trait, inter-specific variation in the bulk amount of DNA in unreplicated somatic cells (2C DNA content), can explain inter-specific variation in the maximum productivity of conifer forests. We expected 2C DNA content to be negatively related to conifer productivity because: 1) it is positively correlated with cell volume (which, in turn, potentially affects structural features such as leaf mass area, a strong predictor of photosynthetic capacity); 2) it is positively correlated with stomatal size (with larger stomata leading to lower overall stomatal conductance and, by extension, lower CO2 uptake); and 3) larger genome sizes may reduce P availability in RNA (which has been hypothesized to slow growth). We present the results of regression and independent contrasts in different monospecific forests encompassing a 52º latitudinal gradient, each being dominated by 1 of 35 different conifer species. Contrary to expectations, we observed a positive correlation between genome size and maximum Gross Primary Productivity (R2 = 0.47) and also between genome size maximum tree height (R2 = 0.27). This correlation was apparently driven by the effects of genome size on stem hydraulics, since 2C DNA was positively correlated with wood density (R2 = 0.40) and also with resistance to cavitation (P50, R2 = 0.28). That is, increased genome sizes have a positive effect on the productivity of conifer forests by affecting the vascular tissues to increase their capacity for water transport. Our results shed a new light on the evolution of the vascular system of conifer forests and how they affect ecosystem productivity, and indicate the potential to

  10. Young Children Learning for the Environment: Researching a Forest Adventure

    ERIC Educational Resources Information Center

    Gambino, Agatha; Davis, Julie; Rowntree, Noeleen

    2009-01-01

    Field experiences for young children are an ideal medium for environmental education/education for sustainability because of opportunities for direct experience in nature, integrated learning, and high community involvement. This research documented the development--in 4-5 year old Prep children--of knowledge, attitudes and actions/advocacy in…

  11. [Annual production of moss layer in dark coniferous forests of Ket-Chulym Forest District (by the example of Moss Hylocomium splendens)].

    PubMed

    Koshurnikova, N N

    2007-01-01

    The biological production of the moss layer was analyzed in dark coniferous stands in progressive succession in the southern taiga in West Siberia. The rate of organic matter production by mosses changed from 15-22.2 g/(m2 y) in 50-90-year-old fir forests to 51.6 g/(m2 y) in 170-year-old mixed Siberian pine-spruce-fir stands. In forest phytocenosis that were formed with species replacement (after cuttings with understory clearing), the annual moss production (net primary production) ranged from 2.8 to 20.6 g/(m2 y). The annual moss cover production amounted to 35-36% of the moss photosynthetic biomass irrespective of the type of native stand progressive succession and the stand age.

  12. Climate-suitable planting as a strategy for maintaining forest productivity and functional diversity.

    PubMed

    Duveneck, Matthew J; Scheller, Robert M

    2015-09-01

    Within the time frame of the longevity of tree species, climate change will change faster than the ability of natural tree migration. Migration lags may result in reduced productivity and reduced diversity in forests under current management and climate change. We evaluated the efficacy of planting climate-suitable tree species (CSP), those tree species with current or historic distributions immediately south of a focal landscape, to maintain or increase aboveground biomass productivity, and species and functional diversity. We modeled forest change with the LANDIS-II forest simulation model for 100 years (2000-2100) at a 2-ha cell resolution and five-year time steps within two landscapes in the Great Lakes region (northeastern Minnesota and northern lower Michigan, USA). We compared current climate to low- and high-emission futures. We simulated a low-emission climate future with the Intergovernmental Panel on Climate Change (IPCC) 2007 B1 emission scenario and the Parallel Climate Model Global Circulation Model (GCM). We simulated a high-emission climate future with the IPCC A1FI emission scenario and the Geophysical Fluid Dynamics Laboratory (GFDL) GCM. We compared current forest management practices (business-as-usual) to CSP management. In the CSP scenario, we simulated a target planting of 5.28% and 4.97% of forested area per five-year time step in the Minnesota and Michigan landscapes, respectively. We found that simulated CSP species successfully established in both landscapes under all climate scenarios. The presence of CSP species generally increased simulated aboveground biomass. Species diversity increased due to CSP; however, the effect on functional diversity was variable. Because the planted species were functionally similar to many native species, CSP did not result in a consistent increase nor decrease in functional diversity. These results provide an assessment of the potential efficacy and limitations of CSP management. These results have

  13. Investigating the controls on Gross Primary Productivity of a high elevation tropical montane cloud forest

    NASA Astrophysics Data System (ADS)

    van de Weg, M. J.; Meir, P.; Malhi, Y.; Williams, M.; Silva-Espejo, J.; Grace, J.

    2012-04-01

    Tropical montane cloud forests (TMCF) are a unique, but little understood ecosystem that can be found in tropical mountainous areas around the world. In recent years, the interest in the carbon (C) cycle of TMCFs has increased, especially with regard to possibilities for carbon sequestration and storage practices. Compared with tropical lowland rainforests, these forests have a low aboveground net primary productivity (ANPP), a small standing biomass and a small leaf area index (LAI), while the forests are characterized by the stunted growth form of the trees. However, estimates of gross primary productivity (GPP) of TMCFs are scarce, and there are uncertainties in what factors are most important in controlling TMCF productivity. We investigated the controlling factors on GPP in a TMCF in the Andes in south east Peru (13°11'28"S / 71°35'24"W). First, we measured physiological and structural parameters of the vegetation. On a leaf level, the carboxylation efficiency of Rubisco (V cmax) and the electron transport capacity (Jmax) were as high as those found in tropical lowland forests, but as expected the LAI was smaller. Therefore, in terms of the capacity for TMCF C uptake, the total leaf area is more important in explaining the difference between TMCF GPP and tropical lowland forest GPP, than photosynthetic capacity of the leaf tissue. Furthermore, we used the vegetation parameters, together with meteorological data from the site with a process based simulator (the SPA model) to simulate TMCF GPP and to evaluate the relative importance of the environmental controls on GPP. To our knowledge, this is the first estimate of TMCF GPP that uses parameters and drivers that are derived from the site simulated in the model. Simulated annual GPP was 16.2 ± SE 1.6 t C ha-1 yr-1, which is about half of the GPP commonly observed in neotropical lowland rainforests. Temperature and, to a lesser extent photosynthetic active radiation (PAR), were the strongest environmental

  14. Improving simulated Amazon forest biomass and productivity by including spatial variation in biophysical parameters

    NASA Astrophysics Data System (ADS)

    Castanho, A. D. A.; Coe, M. T.; Costa, M. H.; Malhi, Y.; Galbraith, D.; Quesada, C. A.

    2013-04-01

    Dynamic vegetation models forced with spatially homogeneous biophysical parameters are capable of producing average productivity and biomass values for the Amazon basin forest biome that are close to the observed estimates, but these models are unable to reproduce observed spatial variability. Recent observational studies have shown substantial regional spatial variability of above-ground productivity and biomass across the Amazon basin, which is believed to be primarily driven by a combination of soil physical and chemical properties. In this study, spatial heterogeneity of vegetation properties is added to the Integrated Biosphere Simulator (IBIS) land surface model, and the simulated productivity and biomass of the Amazon basin are compared to observations from undisturbed forest. The maximum RuBiCo carboxylation capacity (Vcmax) and the woody biomass residence time (τw) were found to be the most important properties determining the modeled spatial variation of above-ground woody net primary productivity and biomass, respectively. Spatial heterogeneity of these properties may lead to simulated spatial variability of 1.8 times in the woody net primary productivity (NPPw) and 2.8 times in the woody above-ground biomass (AGBw). The coefficient of correlation between the modeled and observed woody productivity improved from 0.10 with homogeneous parameters to 0.73 with spatially heterogeneous parameters, while the coefficient of correlation between the simulated and observed woody above-ground biomass improved from 0.33 to 0.88. The results from our analyses with the IBIS dynamic vegetation model demonstrated that using single values for key ecological parameters in the tropical forest biome severely limits simulation accuracy. Clearer understanding of the biophysical mechanisms that drive the spatial variability of carbon allocation, τw and Vcmax is necessary to achieve further improvements to simulation accuracy.

  15. Using mobile distributed pyrolysis facilities to deliver a forest residue resource for bio-fuel production

    NASA Astrophysics Data System (ADS)

    Brown, Duncan

    Distributed mobile conversion facilities using either fast pyrolysis or torrefaction processes can be used to convert forest residues to more energy dense substances (bio-oil, bio-slurry or torrefied wood) that can be transported as feedstock for bio-fuel facilities. All feedstock are suited for gasification, which produces syngas that can be used to synthesise petrol or diesel via Fischer-Tropsch reactions, or produce hydrogen via water gas shift reactions. Alternatively, the bio-oil product of fast pyrolysis may be upgraded to produce petrol and diesel, or can undergo steam reformation to produce hydrogen. Implementing a network of mobile facilities reduces the energy content of forest residues delivered to a bio-fuel facility as mobile facilities use a fraction of the biomass energy content to meet thermal or electrical demands. The total energy delivered by bio-oil, bio-slurry and torrefied wood is 45%, 65% and 87% of the initial forest residue energy content, respectively. However, implementing mobile facilities is economically feasible when large transport distances are required. For an annual harvest of 1.717 million m3 (equivalent to 2000 ODTPD), transport costs are reduced to less than 40% of the total levelised delivered feedstock cost when mobile facilities are implemented; transport costs account for up to 80% of feedstock costs for conventional woodchip delivery. Torrefaction provides the lowest cost pathway of delivering a forest residue resource when using mobile facilities. Cost savings occur against woodchip delivery for annual forest residue harvests above 2.25 million m3 or when transport distances greater than 250 km are required. Important parameters that influence levelised delivered costs of feedstock are transport distances (forest residue spatial density), haul cost factors, thermal and electrical demands of mobile facilities, and initial moisture content of forest residues. Relocating mobile facilities can be optimised for lowest cost

  16. Process-Product Research: A Cornerstone in Educational Effectiveness Research

    ERIC Educational Resources Information Center

    Creemers, Bert; Kyriakides, Leonidas

    2015-01-01

    This article links the contribution of process-product studies in developing the theoretical framework of educational effectiveness by pointing out the importance of teacher behavior in the classroom. The role that Jere Brophy played in this evolving research is described within the various phases of teacher effectiveness research. Process-product…

  17. Determinants of Regional Variability in Litter Production of Forests in the Southern Yucatan: Environmental Gradients or Human Legacy?

    NASA Astrophysics Data System (ADS)

    Lawrence, D.; Lawrence, D.; Foster, D. R.

    2001-05-01

    The Southern Yucatan is the deforestation frontier for the largest block of dry tropical forest north of Brazil. Our goal was to assess how human disturbance alters patterns of productivity driven by natural gradients of precipitation and soil fertility. We sampled litter production and soils in three regions (rainfall 890-1420 mm yr-1). We studied 8-10 stands 2-25 yrs old plus 2-3 mature forest stands per region (36 in total). Litter was collected monthly from four 1-m2 traps within a 500-m2 area, and summed for 1999. Soil chemical and physical properties varied little across the region, but organic matter increased (10.9-13.3% soils 0-15 cm deep) with annual precipitation. Annual litter production was analyzed as a function of region, forest age, number of previous cycles of shifting cultivation, and total number of years in corn production. Region had no significant effect on production, though there was a trend toward higher production in the wettest region. Litterfall increased with age, and production in old secondary forests was not significantly different from that in mature forests. Land-use intensity was negatively correlated with litter production, which declined as a function of both number of cycles and total number of years in corn. In stepwise regression models, age and number of years in corn were the only significant predictors of litter production. Human history, rather than environmental gradients, seems to determine regional variation in productivity in the Yucatan.

  18. Forest Resources

    SciTech Connect

    2016-06-01

    Forest biomass is an abundant biomass feedstock that complements the conventional forest use of wood for paper and wood materials. It may be utilized for bioenergy production, such as heat and electricity, as well as for biofuels and a variety of bioproducts, such as industrial chemicals, textiles, and other renewable materials. The resources within the 2016 Billion-Ton Report include primary forest resources, which are taken directly from timberland-only forests, removed from the land, and taken to the roadside.

  19. Research Productivity: Some Paths Less Travelled

    ERIC Educational Resources Information Center

    Martin, Brian

    2009-01-01

    Conventional approaches for fostering research productivity, such as recruitment and incentives, do relatively little to develop latent capacities in researchers. Six promising unorthodox approaches are the promotion of regular writing, tools for creativity, good luck, happiness, good health and crowd wisdom. These options challenge conventional…

  20. Faculty Research Productivity in Six Arab Countries

    ERIC Educational Resources Information Center

    Abouchedid, Kamal; Abdelnour, George

    2015-01-01

    This article analyses the research output of a sample of higher education institutions (HEIs) in six Arab countries in order to start quantifying academic research productivity in the wider region of the Middle East and North Africa (MENA). A questionnaire classifying HEIs was administered to 310 institutions in Lebanon, Qatar, the United Arab…

  1. Wisconsin timber industry: An assessment of timber product output and use, 1990. Forest Service resource bulletin

    SciTech Connect

    Hackett, R.L.; Whipple, J.W.

    1993-01-01

    In terms of volume of wood used, pulp mills dominate Wisconsin's forest industry, but sawmills far outnumber any other category. There were 323 mills of all types operating in Wisconsin in 1990. Wisconsin is divided into five Survey Units. Industrial roundwood production rose from 328.7 million cubic feet in 1988 to 342.6 million cubic feet in 1990. Pulpwood accounted for 66 percent of the industrial roundwood production in 1990. In 1990, 83 percent of the total growing-stock removals due to harvest came from aspen, red oak, hard maple, red pine, white birch, jack pine, and soft maple.

  2. Modelling changes in nitrogen cycling to sustain increases in forest productivity under elevated atmospheric CO2 and contrasting site conditions

    NASA Astrophysics Data System (ADS)

    Grant, R. F.

    2013-11-01

    If increases in net primary productivity (NPP) caused by rising concentrations of atmospheric CO2 (Ca) are to be sustained, key N processes such as soil mineralization, biological fixation, root uptake and nutrient conservation must also be increased. Simulating the response of these processes to elevated Ca is therefore vital for models used to project the effects of rising Ca on NPP. In this modelling study, hypotheses are proposed for changes in soil mineralization, biological fixation, root nutrient uptake and plant nutrient conservation with changes in Ca. Algorithms developed from these hypotheses were tested in the ecosystem model ecosys against changes in N and C cycling measured over several years under ambient vs. elevated Ca in Free Air CO2 Enrichment (FACE) experiments in the USA at the Duke Forest in North Carolina, the Oak Ridge National Laboratory forest in Tennessee, and the USDA research forest in Wisconsin. More rapid soil N mineralization was found to be vital for simulating sustained increases in NPP measured under elevated vs. ambient Ca at all three FACE sites. This simulation was accomplished by priming decomposition of N-rich humus from increases in microbial biomass generated by increased litterfall modelled under elevated Ca. Greater nonsymbiotic N2 fixation from increased litterfall, root N uptake from increased root growth, and plant N conservation from increased translocation under elevated Ca were found to make smaller contributions to simulated increases in NPP. However greater nutrient conservation enabled larger increases in NPP with Ca to be modelled with coniferous vs. deciduous plant functional types. The effects of these processes on productivity now need to be examined over longer periods under transient rises in Ca and a greater range of site conditions.

  3. The effects of processing non-timber forest products and trade partnerships on people's well-being and forest conservation in Amazonian societies.

    PubMed

    Morsello, Carla; Ruiz-Mallén, Isabel; Diaz, Maria Dolores Montoya; Reyes-García, Victoria

    2012-01-01

    This study evaluated whether processing non-timber forest products (NTFPs) and establishing trade partnerships between forest communities and companies enhance the outcomes of NTFP commercialization. In particular, we evaluated whether product processing, partnerships, or their combination was associated with a number of outcomes related to the well-being of forest inhabitants and forest conservation. We based our analyses on ethnographic and quantitative data (i.e., survey and systematic observations) gathered at seven communities from five societies of the Brazilian and Bolivian Amazon. Our results indicated that product processing and partnerships do not represent a silver bullet able to improve the results of NTFP commercialization in terms of well-being and conservation indicators. Compared with cases without interventions, households adopting partnerships but not product processing were most often associated with improved economic proxies of well-being (total income, NTFP income, food consumption and gender equality in income). In comparison, the combination of product processing and partnerships was associated with similar outcomes. Unexpectedly, product processing alone was associated with negative outcomes in the economic indicators of well-being. All of the investigated strategies were associated with less time spent in social and cultural activities. With respect to forest conservation, the strategies that included a partnership with or without processing produced similar results: while household deforestation tended to decrease, the hunting impact increased. Processing alone was also associated with higher levels of hunting, though it did not reduce deforestation. Our results indicate that establishing partnerships may enhance the outcomes of NTFP trade in terms of the financial outcomes of local communities, but practitioners need to use caution when adopting the processing strategy and they need to evaluate potential negative results for indicators of

  4. The Effects of Processing Non-Timber Forest Products and Trade Partnerships on People's Well-Being and Forest Conservation in Amazonian Societies

    PubMed Central

    Morsello, Carla; Ruiz-Mallén, Isabel; Diaz, Maria Dolores Montoya; Reyes-García, Victoria

    2012-01-01

    This study evaluated whether processing non-timber forest products (NTFPs) and establishing trade partnerships between forest communities and companies enhance the outcomes of NTFP commercialization. In particular, we evaluated whether product processing, partnerships, or their combination was associated with a number of outcomes related to the well-being of forest inhabitants and forest conservation. We based our analyses on ethnographic and quantitative data (i.e., survey and systematic observations) gathered at seven communities from five societies of the Brazilian and Bolivian Amazon. Our results indicated that product processing and partnerships do not represent a silver bullet able to improve the results of NTFP commercialization in terms of well-being and conservation indicators. Compared with cases without interventions, households adopting partnerships but not product processing were most often associated with improved economic proxies of well-being (total income, NTFP income, food consumption and gender equality in income). In comparison, the combination of product processing and partnerships was associated with similar outcomes. Unexpectedly, product processing alone was associated with negative outcomes in the economic indicators of well-being. All of the investigated strategies were associated with less time spent in social and cultural activities. With respect to forest conservation, the strategies that included a partnership with or without processing produced similar results: while household deforestation tended to decrease, the hunting impact increased. Processing alone was also associated with higher levels of hunting, though it did not reduce deforestation. Our results indicate that establishing partnerships may enhance the outcomes of NTFP trade in terms of the financial outcomes of local communities, but practitioners need to use caution when adopting the processing strategy and they need to evaluate potential negative results for indicators of

  5. Tracking changes in the susceptibility of forest land infested with gypsy moth. Forest Service research paper (Final)

    SciTech Connect

    Gansner, D.A.; Quimby, J.W.; King, S.L.; Arner, S.L.; Drake, D.A.

    1994-08-01

    The report questions the forest land subject to intensive outbreaks of gypsy moth (Lymantria dispar L.) which become less susceptible to defoliation. A model for estimating the lifelihood of gypsy moth defoliation has been developed and validated. It was applied to forest-inventory plot data to quantity trends in the susceptibility of forest land in south-central Pennsylvania during a period of intensive infestation. Results show that even though susceptibility of the region's forest apparently has declined, the potential for future infestations remains relatively high.

  6. Plant traits, productivity, biomass and soil properties from forest sites in the Pacific Northwest, 1999–2014

    PubMed Central

    Berner, Logan T.; Law, Beverly E.

    2016-01-01

    Plant trait measurements are needed for evaluating ecological responses to environmental conditions and for ecosystem process model development, parameterization, and testing. We present a standardized dataset integrating measurements from projects conducted by the Terrestrial Ecosystem Research and Regional Analysis- Pacific Northwest (TERRA-PNW) research group between 1999 and 2014 across Oregon and Northern California, where measurements were collected for scaling and modeling regional terrestrial carbon processes with models such as Biome-BGC and the Community Land Model. The dataset contains measurements of specific leaf area, leaf longevity, leaf carbon and nitrogen for 35 tree and shrub species derived from more than 1,200 branch samples collected from over 200 forest plots, including several AmeriFlux sites. The dataset also contains plot-level measurements of forest composition, structure (e.g., tree biomass), and productivity, as well as measurements of soil structure (e.g., bulk density) and chemistry (e.g., carbon). Publically-archiving regional datasets of standardized, co-located, and geo-referenced plant trait measurements will advance the ability of earth system models to capture species-level climate sensitivity at regional to global scales. PMID:26784559

  7. Plant traits, productivity, biomass and soil properties from forest sites in the Pacific Northwest, 1999-2014.

    PubMed

    Berner, Logan T; Law, Beverly E

    2016-01-19

    Plant trait measurements are needed for evaluating ecological responses to environmental conditions and for ecosystem process model development, parameterization, and testing. We present a standardized dataset integrating measurements from projects conducted by the Terrestrial Ecosystem Research and Regional Analysis- Pacific Northwest (TERRA-PNW) research group between 1999 and 2014 across Oregon and Northern California, where measurements were collected for scaling and modeling regional terrestrial carbon processes with models such as Biome-BGC and the Community Land Model. The dataset contains measurements of specific leaf area, leaf longevity, leaf carbon and nitrogen for 35 tree and shrub species derived from more than 1,200 branch samples collected from over 200 forest plots, including several AmeriFlux sites. The dataset also contains plot-level measurements of forest composition, structure (e.g., tree biomass), and productivity, as well as measurements of soil structure (e.g., bulk density) and chemistry (e.g., carbon). Publically-archiving regional datasets of standardized, co-located, and geo-referenced plant trait measurements will advance the ability of earth system models to capture species-level climate sensitivity at regional to global scales.

  8. Plant traits, productivity, biomass and soil properties from forest sites in the Pacific Northwest, 1999-2014

    NASA Astrophysics Data System (ADS)

    Berner, Logan T.; Law, Beverly E.

    2016-01-01

    Plant trait measurements are needed for evaluating ecological responses to environmental conditions and for ecosystem process model development, parameterization, and testing. We present a standardized dataset integrating measurements from projects conducted by the Terrestrial Ecosystem Research and Regional Analysis- Pacific Northwest (TERRA-PNW) research group between 1999 and 2014 across Oregon and Northern California, where measurements were collected for scaling and modeling regional terrestrial carbon processes with models such as Biome-BGC and the Community Land Model. The dataset contains measurements of specific leaf area, leaf longevity, leaf carbon and nitrogen for 35 tree and shrub species derived from more than 1,200 branch samples collected from over 200 forest plots, including several AmeriFlux sites. The dataset also contains plot-level measurements of forest composition, structure (e.g., tree biomass), and productivity, as well as measurements of soil structure (e.g., bulk density) and chemistry (e.g., carbon). Publically-archiving regional datasets of standardized, co-located, and geo-referenced plant trait measurements will advance the ability of earth system models to capture species-level climate sensitivity at regional to global scales.

  9. Major forest changes and land cover transitions based on plant functional types derived from the ESA CCI Land Cover product

    NASA Astrophysics Data System (ADS)

    Li, Wei; Ciais, Philippe; MacBean, Natasha; Peng, Shushi; Defourny, Pierre; Bontemps, Sophie

    2016-05-01

    Land use and land cover change are of prime concern due to their impacts on CO2 emissions, climate change and ecological services. New global land cover products at 300 m resolution from the European Space Agency (ESA) Climate Change Initiative Land Cover (CCI LC) project for epochs centered around 2000, 2005 and 2010 were analyzed to investigate forest area change and land cover transitions. Plant functional types (PFTs) fractions were derived from these land cover products according to a conversion table. The gross global forest loss between 2000 and 2010 is 172,171 km2, accounting for 0.6% of the global forest area in year 2000. The forest changes are mainly distributed in tropical areas such as Brazil and Indonesia. Forest gains were only observed between 2005 and 2010 with a global area of 9844 km2, mostly from crops in Southeast Asia and South America. The predominant PFT transition is deforestation from forest to crop, accounting for four-fifths of the total increase of cropland area between 2000 and 2010. The transitions from forest to bare soil, shrub, and grass also contributed strongly to the total areal change in PFTs. Different PFT transition matrices and composition patterns were found in different regions. The highest fractions of forest to bare soil transitions were found in the United States and Canada, reflecting forest management practices. Most of the degradation from grassland and shrubland to bare soil occurred in boreal regions. The areal percentage of forest loss and land cover transitions generally decreased from 2000-2005 to 2005-2010. Different data sources and uncertainty in the conversion factors (converting from original LC classes to PFTs) contribute to the discrepancy in the values of change in absolute forest area.

  10. Utilizing intraspecific variation in phenotypic plasticity to bolster agricultural and forest productivity under climate change.

    PubMed

    Aspinwall, Michael J; Loik, Michael E; Resco de Dios, Victor; Tjoelker, Mark G; Payton, Paxton R; Tissue, David T

    2015-09-01

    Climate change threatens the ability of agriculture and forestry to meet growing global demands for food, fibre and wood products. Information gathered from genotype-by-environment interactions (G × E), which demonstrate intraspecific variation in phenotypic plasticity (the ability of a genotype to alter its phenotype in response to environmental change), may prove important for bolstering agricultural and forest productivity under climate change. Nonetheless, very few studies have explicitly quantified genotype plasticity-productivity relationships in agriculture or forestry. Here, we conceptualize the importance of intraspecific variation in agricultural and forest species plasticity, and discuss the physiological and genetic factors contributing to intraspecific variation in phenotypic plasticity. Our discussion highlights the need for an integrated understanding of the mechanisms of G × E, more extensive assessments of genotypic responses to climate change under field conditions, and explicit testing of genotype plasticity-productivity relationships. Ultimately, further investigation of intraspecific variation in phenotypic plasticity in agriculture and forestry may prove important for identifying genotypes capable of increasing or sustaining productivity under more extreme climatic conditions.

  11. TRC research products: Components for service robots

    NASA Technical Reports Server (NTRS)

    Lob, W. Stuart

    1994-01-01

    Transitions Research Corporation has developed a variety of technologies to accomplish its central mission: the creation of commercially viable robots for the service industry. Collectively, these technologies comprise the TRC 'robot tool kit.' The company started by developing a robot base that serves as a foundation for mobile robot research and development, both within TRC and at customer sites around the world. A diverse collection of sensing techniques evolved more recently, many of which have been made available to the international mobile robot research community as commercial products. These 'tool-kit' research products are described in this paper. The largest component of TRC's commercial operation is a product called HelpMate for material transport and delivery in health care institutions.

  12. Update on geriatric research in productive aging.

    PubMed

    Murphy, Susan L

    2011-01-01

    The American Occupational Therapy Association's Centennial Vision articulates the strategic goals for the profession to be science driven and evidence based in major practice areas. In the practice area of productive aging, a previous review of research published in the American Journal of Occupational Therapy (AJOT) found mostly basic research with far fewer effectiveness studies. The current review article is divided into two parts. Part 1 provides an update on the types of research published on productive aging in AJOT in the past 2 yr (2009-2010). Part 2 examines the range and scope of occupational therapy effectiveness research on productive aging published in a similar time frame in other occupational therapy journals and outside of the discipline.

  13. CONSTRAINTS ON IONIZING PHOTON PRODUCTION FROM THE LARGE-SCALE Lyα FOREST

    SciTech Connect

    Pontzen, Andrew; Peiris, Hiranya; Bird, Simeon; Verde, Licia

    2014-09-10

    Recent work has shown that the z ≅ 2.5 Lyα forest on large scales encodes information about the galaxy and quasar populations that keep the intergalactic medium photoionized. We present the first forecasts for constraining the populations with data from current and next-generation surveys. At a minimum, the forest should tell us whether galaxies or, conversely, quasars dominate the photon production. The number density and clustering strength of the ionizing sources might be estimated to sub-10% precision with a DESI-like survey if degeneracies (e.g., with the photon mean-free-path, small-scale clustering power normalization, and potentially other astrophysical effects) can be broken by prior information. We demonstrate that when inhomogeneous ionization is correctly handled, constraints on dark energy do not degrade.

  14. Applying environmental product design to biomedical products research.

    PubMed Central

    Messelbeck, J; Sutherland, L

    2000-01-01

    The principal themes for the Biomedical Research and the Environment Conference Committee on Environmental Economics in Biomedical Research include the following: healthcare delivery companies and biomedical research organizations, both nonprofit and for-profit, need to improve their environmental performance; suppliers of healthcare products will be called upon to support this need; and improving the environmental profile of healthcare products begins in research and development (R&D). The committee report begins with requirements from regulatory authorities (e.g., U.S. Environmental Protection Agency [EPA], the U.S. Food and Drug Administration), and the healthcare delivery sector). The 1998 American Hospital Association and EPA Memorandum of Understanding to reduce solid waste and mercury from healthcare facilities is emblematic of these requirements. The dominant message from the requirements discussion is to ensure that R&D organizations do not ignore customer, environmental, and regulatory requirements in the early stages of product development. Several representatives from healthcare products manufacturers presented their companies' approaches to meeting these requirements. They reported on efforts to ensure that their R&D processes are sensitive to the environmental consequences from manufacturing, distributing, using, and disposing of healthcare products. These reports describe representatives' awareness of requirements and the unique approaches their R&D organizations have taken to meet these requirements. All representatives reported that their R&D organizations have embraced environmental product design because it avoids the potential of returning products to R&D to improve the environmental profile. Additionally, several reports detailed cost savings, sustainability benefits, and improvements in environmental manufacturing or redesign, and increased customer satisfaction. Many companies in healthcare delivery are working to improve environmental

  15. Applying environmental product design to biomedical products research.

    PubMed

    Messelbeck, J; Sutherland, L

    2000-12-01

    The principal themes for the Biomedical Research and the Environment Conference Committee on Environmental Economics in Biomedical Research include the following: healthcare delivery companies and biomedical research organizations, both nonprofit and for-profit, need to improve their environmental performance; suppliers of healthcare products will be called upon to support this need; and improving the environmental profile of healthcare products begins in research and development (R&D). The committee report begins with requirements from regulatory authorities (e.g., U.S. Environmental Protection Agency [EPA], the U.S. Food and Drug Administration), and the healthcare delivery sector). The 1998 American Hospital Association and EPA Memorandum of Understanding to reduce solid waste and mercury from healthcare facilities is emblematic of these requirements. The dominant message from the requirements discussion is to ensure that R&D organizations do not ignore customer, environmental, and regulatory requirements in the early stages of product development. Several representatives from healthcare products manufacturers presented their companies' approaches to meeting these requirements. They reported on efforts to ensure that their R&D processes are sensitive to the environmental consequences from manufacturing, distributing, using, and disposing of healthcare products. These reports describe representatives' awareness of requirements and the unique approaches their R&D organizations have taken to meet these requirements. All representatives reported that their R&D organizations have embraced environmental product design because it avoids the potential of returning products to R&D to improve the environmental profile. Additionally, several reports detailed cost savings, sustainability benefits, and improvements in environmental manufacturing or redesign, and increased customer satisfaction. Many companies in healthcare delivery are working to improve environmental

  16. CO2 Enhancement of Forest Productivity Constrained by Limited Nitrogen Availability

    SciTech Connect

    Norby, Richard J; Warren, Jeffrey; Iversen, Colleen M; Medlyn, Belinda; McMurtrie, Ross

    2010-01-01

    Stimulation of terrestrial productivity by rising CO2 concentration is projected to reduce the airborne fraction of anthropogenic CO2 emissions; coupled climate-carbon (C) cycle models, including those used in the IPCC Fourth Assessment Report (AR4), are sensitive to this negative feedback on atmospheric CO2 1. The representation of the so-called CO2 fertilization effect in the 11 models used in AR4 and subsequent models2,3 was broadly consistent with experimental evidence from four free-air CO2 enrichment (FACE) experiments, which indicated that net primary productivity (NPP) of forests was increased by 23 2% in response to atmospheric CO2 enrichment to 550 ppm4. Substantial uncertainty remains, however, because of the expectation that feedbacks through the nitrogen (N) cycle will reduce the CO2 stimulation of NPP5,6; these feedbacks were not included in the AR4 models and heretofore have not been confirmed by experiments in forests7. Here, we provide new evidence from a FACE experiment in a deciduous Liquidambar styraciflua (sweetgum) forest stand in Tennessee, USA, that N limitation has significantly reduced the stimulation of NPP by elevated atmospheric CO2 concentration (eCO2). Isotopic evidence and N budget analysis support the premise that N availability in this forest ecosystem has been declining over time, and declining faster in eCO2. Model analyses and evidence from leaf- and stand-level observations provide mechanistic evidence that declining N availability constrained the tree response to eCO2. These results provide a strong rationale and process understanding for incorporating N limitation and N feedback effects in ecosystem and global models used in climate change assessments.

  17. Faculty research productivity in six Arab countries

    NASA Astrophysics Data System (ADS)

    Abouchedid, Kamal; Abdelnour, George

    2015-10-01

    This article analyses the research output of a sample of higher education institutions (HEIs) in six Arab countries in order to start quantifying academic research productivity in the wider region of the Middle East and North Africa (MENA). A questionnaire classifying HEIs was administered to 310 institutions in Lebanon, Qatar, the United Arab Emirates (UAE), Morocco, Saudi Arabia and Jordan. The study revealed a lack of capacity of HEIs to provide quality data, raising issues concerning institutional excellence and transparency. Those data which were available were analysed using a number of statistical methods. The result is that faculty research output in the Arab world is relatively low, confirming the existing notion of a lagging knowledge sector in the region. While traditional scholarship has focused on institutional factors such as budgetary allocation as one prime determinant of research productivity, this study claims that other factors need to be considered in explaining the low output, with broad implications for policy formulation. Such factors include overall satisfaction levels of academic staff, socialisation of faculty staff members into a research climate, and university mission vis-à-vis academic research. Given the distinct paucity of studies on faculty research productivity in HEIs in the Arab region, this study seeks to bridge this gap in the literature by providing original data derived from six Arab countries. The authors aim to provide a basis for further research into this topic.

  18. Renewal of Collaborative Research: Economically viable Forest Harvesting Practices that Increase Carbon Sequestration

    SciTech Connect

    Dail, David Bryan

    2012-08-02

    This technical report covers a 3-year cooperative agreement between the University of Maine and the Northeastern Forest Experiment Station that focused on the characterization of forest stands and the assessment of forest carbon storage (see attached for detailed description of the project). The goal of this work was to compare estimates of forest C storage made via remeasurement of FIA-type plots with eddy flux measurements. In addition to relating whole ecosystem estimates of carbon storage to changes in aboveground biomass, we explored methodologies by partitioning growth estimates from periodic inventory measurements into annual estimates. In the final year, we remeasured plots that were subject to a shelterwood harvest over the winter of 2001-02 to assess the production of coarse woody debris by this harvest, to remeasure trees in a long-term stand first established by NASA, to carry out other field activities at Howland, and, to assess the importance of downed and decaying wood as well as standing dead trees to the C inputs to harvested and non harvested plots.

  19. Managing the world's forests.

    PubMed

    Sharma, N; Rowe, R

    1992-06-01

    Forests play a vital role in balancing natural systems: the stabilization of global climate and the management of water and land. 30% of the earth's total land area is forested. 66% of the tropical moist forests are in Latin America and the remainder in Africa and Asia. 75% of tropical dry forests are in Africa. Temperate forests are primarily in developed countries. Deforestation and misuse of forests occurs primarily in developing countries at significant social, economic, and environmental costs. Losses have occurred in fuelwood, fodder, timber, forest products, biological diversity, habitats, genetic materials for food and medicine. The World Bank's evolving role in forestry is briefly described. Agreement has not been reached among people or nations about the most appropriate means to balance conservation and development goals. The challenge is to stabilize existing forests and increase forest planting. The causes of forest degradation must be understood. Direct causes include agricultural encroachment, cattle ranching, fuelwood gathering, commercial logging, and infrastructure development. These direct causes are driven by economic, social, and political forces: market and policy failures, population growth, and poverty. The market failures include: 1) the lack of clearly defined property rights on forest resources for now and the future, 2) the conflict between individual and societal needs, 3) the difficulty in placing a value on nonmarket environmental services and joint products, and 4) the separation between private and social costs. The solution is action at the local, national, and global levels. Countries must establish forest policy. The existing government incentives which promote deforestation must be changed. For example, concession policy and royalty systems must be corrected; explicit and implicit export subsidies on timber and forest products must be stopped. Private incentives must be established to promote planting of trees, practicing

  20. Mapping resource use over a Russian landscape: an integrated look at harvesting of a non-timber forest product in central Kamchatka

    NASA Astrophysics Data System (ADS)

    Hitztaler, Stephanie K.; Bergen, Kathleen M.

    2013-12-01

    Small-scale resource use became an important adaptive mechanism in remote logging communities in Russia at the onset of the post-Soviet period in 1991. We focused on harvesting of a non-timber forest product, lingonberry (Vaccinium vitis-idaea), in the forests of the Kamchatka Peninsula (Russian Far East). We employed an integrated geographical approach to make quantifiable connections between harvesting and the landscape, and to interpret these relationships in their broader contexts. Landsat TM images were used for a new classification; the resulting land-cover map was the basis for linking non-spatial data on harvesters’ gathering behaviors to spatial data within delineated lingonberry gathering sites. Several significant relationships emerged: (1) mature forests negatively affected harvesters’ initial choice to gather in a site, while young forests had a positive effect; (2) land-cover type was critical in determining how and why gathering occurred: post-disturbance young and maturing forests were significantly associated with higher gathering intensity and with the choice to market harvests; and (3) distance from gathering sites to villages and main roads also mattered: longer distances were significantly correlated to more time spent gathering and to increased marketing of harvests. We further considered our findings in light of the larger ecological and social dynamics at play in central Kamchatka. This unique study is an important starting point for conservation- and sustainable development-based work, and for additional research into the drivers of human-landscape interactions in the Russian Far East.

  1. 36 CFR 223.219 - Sustainable harvest of special forest products.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... making their sustainability determination and establishing monitoring time frames consistent with... Forest Service shall monitor the effects of harvesting on the sustainability of special forest...

  2. Impact of research investment on scientific productivity of junior researchers.

    PubMed

    Farrokhyar, Forough; Bianco, Daniela; Dao, Dyda; Ghert, Michelle; Andruszkiewicz, Nicole; Sussman, Jonathan; Ginsberg, Jeffrey S

    2016-12-01

    There is a demand for providing evidence on the effectiveness of research investments on the promotion of novice researchers' scientific productivity and production of research with new initiatives and innovations. We used a mixed method approach to evaluate the funding effect of the New Investigator Fund (NIF) by comparing scientific productivity between award recipients and non-recipients. We reviewed NIF grant applications submitted from 2004 to 2013. Scientific productivity was assessed by confirming the publication of the NIF-submitted application. Online databases were searched, independently and in duplicate, to locate the publications. Applicants' perceptions and experiences were collected through a short survey and categorized into specified themes. Multivariable logistic regression was performed. Odds ratios (OR) with 95 % confidence intervals (CI) are reported. Of 296 applicants, 163 (55 %) were awarded. Gender, affiliation, and field of expertise did not affect funding decisions. More physicians with graduate education (32.0 %) and applicants with a doctorate degree (21.5 %) were awarded than applicants without postgraduate education (9.8 %). Basic science research (28.8 %), randomized controlled trials (24.5 %), and feasibility/pilot trials (13.3 %) were awarded more than observational designs (p   <  0.001). Adjusting for applicants and application factors, awardees published the NIF application threefold more than non-awardees (OR = 3.4, 95 %, CI = 1.9, 5.9). The survey response rate was 90.5 %, and only 58 % commented on their perceptions, successes, and challenges of the submission process. These findings suggest that research investments as small as seed funding are effective for scientific productivity and professional growth of novice investigators and production of research with new initiatives and innovations. Further efforts are recommended to enhance the support of small grant funding programs.

  3. Community structure and primary productivity of forested wetlands in western Kentucky

    SciTech Connect

    Taylor, J.R.

    1985-01-01

    Community structure and net primary productivity were measured in five forested wetlands in western Kentucky and compared with hydrologic information. A bottomland hardwood forest (H1), cypress-ash swamp (H2), and deep cypress swamp (H3) were located on the floodplain of the Ohio River and were subject to annual spring flooding. The other two sites were adjacent to a smaller, channelized stream that floods frequently, but for short periods. Only a young riparian forest (C3) is directly affected by the stream unless an unusually severe flood exceeds the levee that hydrologically isolates the stagnant cypress swamp (C4). Community structure indices were lowest in the two permanently-flooded cypress swamps. Tree biomass was 9.4 kg/m/sup 2/ at C4 and 10.2 kg/m/sup 2/ at H3. High biomass was found at H1 and H2 (30.3 and 31.2 kg/m/sup 2/) while C3 was intermediate at 18.4 kg/m/sup 2/. Other structural measures, notably stem density and mean height were closely related to biomass estimates. Low leaf to wood biomass ratios were found at H2 and C4 which suggests low nutrient availability. Nutrients are abundant at H2 due to agricultural runoff but physiological stress and aquatic macrophyte competition may limit tree uptake.

  4. Estimating daytime ecosystem respiration to improve estimates of gross primary production of a temperate forest.

    PubMed

    Sun, Jinwei; Wu, Jiabing; Guan, Dexin; Yao, Fuqi; Yuan, Fenghui; Wang, Anzhi; Jin, Changjie

    2014-01-01

    Leaf respiration is an important component of carbon exchange in terrestrial ecosystems, and estimates of leaf respiration directly affect the accuracy of ecosystem carbon budgets. Leaf respiration is inhibited by light; therefore, gross primary production (GPP) will be overestimated if the reduction in leaf respiration by light is ignored. However, few studies have quantified GPP overestimation with respect to the degree of light inhibition in forest ecosystems. To determine the effect of light inhibition of leaf respiration on GPP estimation, we assessed the variation in leaf respiration of seedlings of the dominant tree species in an old mixed temperate forest with different photosynthetically active radiation levels using the Laisk method. Canopy respiration was estimated by combining the effect of light inhibition on leaf respiration of these species with within-canopy radiation. Leaf respiration decreased exponentially with an increase in light intensity. Canopy respiration and GPP were overestimated by approximately 20.4% and 4.6%, respectively, when leaf respiration reduction in light was ignored compared with the values obtained when light inhibition of leaf respiration was considered. This study indicates that accurate estimates of daytime ecosystem respiration are needed for the accurate evaluation of carbon budgets in temperate forests. In addition, this study provides a valuable approach to accurately estimate GPP by considering leaf respiration reduction in light in other ecosystems.

  5. Research for the development of best management practices for minimizing horse trail impacts on the Hoosier National Forest

    USGS Publications Warehouse

    Aust, M.W.; Marion, J.L.; Kyle, K.

    2005-01-01

    This research investigates horse trail impacts to gain an improved understanding of the relationship between various levels of horse use, horse trail management alternatives, and subsequent horse trail degradation. A survey of existing horse trails on the Hoosier National Forest was used to collect data on use-related, environmental and management factors to model horse trail impacts. Results are analyzed to identify which factors are most easily manipulated by managers to effectively avoid and minimize horse trail impacts. A specific focus includes evaluating the relative effect of trail use level, surfacing, grade, and water control on indices of erosion and trafficability such as trail cross sectional area, estimated erosion, muddiness, and incision. Overall, the Hoosier National Forest horse trails could be significantly improved by relocating or closing inherited trails that directly ascend slope or are excessively steep, reducing the distance between water control structures, and by applying gravel to harden trail surfaces and reduce soil erosion. A set of Best Management Practices for trails are included as a product of this work, with recommendations based on this research.

  6. Satellite-based products for forest fire prevention and recovery: the PREFER experience

    NASA Astrophysics Data System (ADS)

    Laneve, Giovanni; Bernini, Guido; Fusilli, Lorenzo; Marzialetti, Pablo

    2016-08-01

    PREFER is a three years projects funded in 2012 in the framework of the FP7 Emergency call. The project objective was to set up a space-based service infrastructure and up-to-date cartographic products, based on remote sensing data, to support the preparedness, prevention, recovery and reconstruction phases of the Forest Fires emergency cycle in the European Mediterranean Region. The products of PREFER were tested and evaluated during the training and the demonstration period of the project, which coincided with the forest fire season of 2015. The products were tested using the online PREFER service and the tests were linked to the pilot areas of the project which are Minho (Portugal), Messenia (Greece), Andalucía (Spain), Sardinia (Italy) and Corse (France). Testing was performed by members of the User Advisory Board (UAB) starting from the training event organized in Coimbra, Portugal in June 2015. The tests continued till the end of the fire season (October 2015) and the end users were provided with updated information for the areas of interest during the entire demonstration period. Due to data availability restrictions (in particular to ancillary required data) not all products were available for testing in all the test areas. However all the PREFER products were tested at least in one pilot area and in cooperation with at least one end user organization. It has to be mentioned that beyond the product suitability and usefulness to the end users the tests included evaluation of the usability of the web-based service of PREFER and the respective quality of service provided. This paper aims at presenting the results of the demonstration activity, the lessons learned and ideas for further enhancement of the developed products devoted to support prevention and recovery phases of the wildfire cycle.

  7. Application of a Hybrid Forest Growth Model to Evaluate Climate Change Impacts on Productivity, Nutrient Cycling and Mortality in a Montane Forest Ecosystem

    PubMed Central

    Seely, Brad; Welham, Clive; Scoullar, Kim

    2015-01-01

    Climate change introduces considerable uncertainty in forest management planning and outcomes, potentially undermining efforts at achieving sustainable practices. Here, we describe the development and application of the FORECAST Climate model. Constructed using a hybrid simulation approach, the model includes an explicit representation of the effect of temperature and moisture availability on tree growth and survival, litter decomposition, and nutrient cycling. The model also includes a representation of the impact of increasing atmospheric CO2 on water use efficiency, but no direct CO2 fertilization effect. FORECAST Climate was evaluated for its ability to reproduce the effects of historical climate on Douglas-fir and lodgepole pine growth in a montane forest in southern British Columbia, Canada, as measured using tree ring analysis. The model was subsequently used to project the long-term impacts of alternative future climate change scenarios on forest productivity in young and established stands. There was a close association between predicted sapwood production and measured tree ring chronologies, providing confidence that model is able to predict the relative impact of annual climate variability on tree productivity. Simulations of future climate change suggest a modest increase in productivity in young stands of both species related to an increase in growing season length. In contrast, results showed a negative impact on stemwood biomass production (particularly in the case of lodgepole pine) for established stands due to increased moisture stress mortality. PMID:26267446

  8. Application of a Hybrid Forest Growth Model to Evaluate Climate Change Impacts on Productivity, Nutrient Cycling and Mortality in a Montane Forest Ecosystem.

    PubMed

    Seely, Brad; Welham, Clive; Scoullar, Kim

    2015-01-01

    Climate change introduces considerable uncertainty in forest management planning and outcomes, potentially undermining efforts at achieving sustainable practices. Here, we describe the development and application of the FORECAST Climate model. Constructed using a hybrid simulation approach, the model includes an explicit representation of the effect of temperature and moisture availability on tree growth and survival, litter decomposition, and nutrient cycling. The model also includes a representation of the impact of increasing atmospheric CO2 on water use efficiency, but no direct CO2 fertilization effect. FORECAST Climate was evaluated for its ability to reproduce the effects of historical climate on Douglas-fir and lodgepole pine growth in a montane forest in southern British Columbia, Canada, as measured using tree ring analysis. The model was subsequently used to project the long-term impacts of alternative future climate change scenarios on forest productivity in young and established stands. There was a close association between predicted sapwood production and measured tree ring chronologies, providing confidence that model is able to predict the relative impact of annual climate variability on tree productivity. Simulations of future climate change suggest a modest increase in productivity in young stands of both species related to an increase in growing season length. In contrast, results showed a negative impact on stemwood biomass production (particularly in the case of lodgepole pine) for established stands due to increased moisture stress mortality.

  9. Stream invertebrate productivity linked to forest subsidies: 37 stream-years of reference and experimental data.

    PubMed

    Wallace, J Bruce; Eggert, Susan L; Meyer, Judy L; Webster, Jackson R

    2015-05-01

    Riparian habitats provide detrital subsidies of varying quantities and qualities to recipient ecosystems. We used long-term data from three reference streams (covering 24 stream-years) and 13-year whole-stream organic matter manipulations to investigate the influence of terrestrial detrital quantity and quality on benthic invertebrate community structure, abundance, biomass, and secondary production in rockface (RF) and mixed substrates (MS) of forested headwater streams. Using a mesh canopy covering the entire treatment stream, we examined effects of litter ex'clusion, small- and large-wood removal, and addition of artificial wood (PVC) and leaves of varying quality on organic matter standing crops and invertebrate community structure and function. We assessed differences in functional feeding group distribution between substrate types as influenced by organic matter manipulations and long-term patterns of predator and prey production in manipulated vs. reference years. Particulate organic matter standing crops in MS of the treatment stream declined drastically with each successive year of litter exclusion, approaching zero after three years. Monthly invertebrate biomass and annual secondary production was positively related to benthic organic matter in the MS habitats. Rockface habitats exhibited fewer changes than MS habitats across all organic matter manipulations. With leaf addition, the patterns of functional group distribution among MS and RF habitats returned to patterns seen in reference streams. Secondary production per unit organic matter standing crop was greatest for the leaf addition period, followed by the reference streams, and significantly less for the litter exclusion and wood removal periods. These data indicate that the limited organic matter remaining in the stream following litter exclusion and wood removal was more refractory than that in the reference streams, whereas the added leaf material was more labile and readily converted into

  10. Remote sensing of net ecosystem productivity based on component spectrum and soil respiration observation in boreal forest, interior Alaska.

    NASA Astrophysics Data System (ADS)

    Kushida, K.; Kim, Y.; Tanaka, N.; Fukuda, M.

    2003-12-01

    We built a remote sensing method for leaf area index (LAI) and ground cover mosses / lichens in boreal forest by field component spectral observation and radiative transfer modeling based on the spectrum. The method was applied to evaluate annual net ecosystem productivity (NEP) distribution in boreal forest, interior Alaska by combining soil respiration observation synchronized to the spectral observation. Spectral reflectance and soil respiration were observed in two 30m X 30m plots in black spruce stands, central Alaska. Spectral characteristics of the forest floor and the needle leaves were used as input parameters of a radiative transfer model to evaluate nadir reflectances of spruce communities in relation to varying upper layer LAI, forest floor bryophyte types, and leaf spectral characteristics. Using the relationship, we obtained LAI and bryophyte area ratios for each pixel that corresponds to spruce forest on Landsat ETM+ imagery. The LAI-NPP relationship was estimated from Plonski's normal yield table data and specific leaf area, and NPP was calculated from LAI. Based on the observed annual soil respiration and NPP of upper layer and forest floor, annual NEP geographical distribution was estimated as a mean value in recent 30-100 years from remotely sensed LAI and forest floor bryophyte area ratios. The annually estimated NEP was 51 gC/m2/year, which corresponds to the value (55 gC/m2/year) of 150-year-old black spruce forest in the BOREAS study region, Canada.

  11. Relationships among net primary productivity, nutrients and climate in tropical rain forest: A pan-tropical analysis

    USGS Publications Warehouse

    Cleveland, Cory C.; Townsend, Alan R.; Taylor, Philip; Alvarez-Clare, Silvia; Bustamante, Mercedes M.C.; Chuyong, George; Dobrowski, Solomon Z.; Grierson, Pauline; Harms, Kyle E.; Houlton, Benjamin Z.; Marklein, Alison; Parton, William; Porder, Stephen; Reed, Sasha C.; Sierra, Carlos A.; Silver, Whendee L.; Tanner, Edmund V.J.; Wieder, William R.

    2011-01-01

    Tropical rain forests play a dominant role in global biosphere-atmosphere CO2 exchange. Although climate and nutrient availability regulate net primary production (NPP) and decomposition in all terrestrial ecosystems, the nature and extent of such controls in tropical forests remain poorly resolved. We conducted a meta-analysis of carbon-nutrient-climate relationships in 113 sites across the tropical forest biome. Our analyses showed that mean annual temperature was the strongest predictor of aboveground NPP (ANPP) across all tropical forests, but this relationship was driven by distinct temperature differences between upland and lowland forests. Within lowland forests (< 1000 m), a regression tree analysis revealed that foliar and soil-based measurements of phosphorus (P) were the only variables that explained a significant proportion of the variation in ANPP, although the relationships were weak. However, foliar P, foliar nitrogen (N), litter decomposition rate (k), soil N and soil respiration were all directly related with total surface (0–10 cm) soil P concentrations. Our analysis provides some evidence that P availability regulates NPP and other ecosystem processes in lowland tropical forests, but more importantly, underscores the need for a series of large-scale nutrient manipulations – especially in lowland forests – to elucidate the most important nutrient interactions and controls.

  12. Trading forests: land-use change and carbon emissions embodied in production and exports of forest-risk commodities

    NASA Astrophysics Data System (ADS)

    Henders, Sabine; Persson, U. Martin; Kastner, Thomas

    2015-12-01

    Production of commercial agricultural commodities for domestic and foreign markets is increasingly driving land clearing in tropical regions, creating links and feedback effects between geographically separated consumption and production locations. Such teleconnections are commonly studied through calculating consumption footprints and quantifying environmental impacts embodied in trade flows, e.g., virtual water and land, biomass, or greenhouse gas emissions. The extent to which land-use change (LUC) and associated carbon emissions are embodied in the production and export of agricultural commodities has been less studied. Here we quantify tropical deforestation area and carbon emissions from LUC induced by the production and the export of four commodities (beef, soybeans, palm oil, and wood products) in seven countries with high deforestation rates (Argentina, Bolivia, Brazil, Paraguay, Indonesia, Malaysia, and Papua New Guinea). We show that in the period 2000-2011, the production of the four analyzed commodities in our seven case countries was responsible for 40% of total tropical deforestation and resulting carbon losses. Over a third of these impacts was embodied in exports in 2011, up from a fifth in 2000. This trend highlights the growing influence of global markets in deforestation dynamics. Main flows of embodied LUC are Latin American beef and soybean exports to markets in Europe, China, the former Soviet bloc, the Middle East and Northern Africa, whereas embodied emission flows are dominated by Southeast Asian exports of palm oil and wood products to consumers in China, India and the rest of Asia, as well as to the European Union. Our findings illustrate the growing role that global consumers play in tropical LUC trajectories and highlight the need for demand-side policies covering whole supply chains. We also discuss the limitations of such demand-side measures and call for a combination of supply- and demand-side policies to effectively limit tropical

  13. Modelling changes in nitrogen cycling to sustain increases in forest productivity under elevated atmospheric CO2 and contrasting site conditions

    NASA Astrophysics Data System (ADS)

    Grant, R. F.

    2013-04-01

    If increases in net primary productivity (NPP) caused by rising concentrations of atmospheric CO2 (Ca) are to be sustained, key N processes such as soil mineralization, biological fixation, root uptake and plant translocation must be hastened. Simulating the response of these processes to elevated Ca is therefore vital for models used to project the effects of rising Ca on NPP. In this modelling study, hypotheses are proposed for changes in soil mineralization, biological fixation, root uptake and plant translocation with changes in Ca. Algorithms developed from these hypotheses were tested in the ecosystem model ecosys against changes in N and C cycling measured over several years under ambient vs. elevatedCa in Free Air CO2 Enrichment (FACE) experiments at the Duke Forest in North Carolina, the Oak Ridge National Laboratory forest in Tennessee, and the USDA research forest in Wisconsin, USA. Simulating more rapid soil N mineralization was found to be vital for modelling sustained increases in NPP measured under elevated vs. ambient Ca at all three FACE sites. This simulation was accomplished by priming decomposition of N-rich humus from increases in microbial biomass generated by increased litterfall modelled under elevated Ca. Simulating more rapid nonsymbiotic N2 fixation, root N uptake and plant N translocation under elevated Ca was found to make much smaller contributions to modelled increases in NPP, although such contributions might be greater over longer periods and under more N-limited conditions than those simulated here. Greater increases in NPP with Ca were also modelled with increased temperature and water stress, and with coniferous vs. deciduous plant functional types. These increases were also associated with changes in N cycling.

  14. Leaf Caloric Value from Tropical to Cold-Temperate Forests: Latitudinal Patterns and Linkage to Productivity.

    PubMed

    Song, Guangyan; Hou, Jihua; Li, Ying; Zhang, Jiahui; He, Nianpeng

    2016-01-01

    Leaf caloric value (LCV) reflects the capacity of a leaf to fix and accumulate solar energy through photosynthesis. We systematically investigated the LCV of 745 plant species in 9 forests, representing a range of tropical to cold-temperate forests along the 4700-km North-South Transect of Eastern China. The goals were to explore the latitudinal patterns of LCV at the levels of species, plant functional group, and community and to establish the relationship between LCV and gross primary productivity (GPP). Our results showed that LCV for all species ranged from 12.85 to 22.15 KJ g-1 with an average of 18.46 KJ g-1. Plant functional groups had a significant influence on LCV, with trees > shrubs > herbs, conifers > broadleaved trees, and evergreens > deciduous trees. The different values of LCV represented the long-term evolution and adaptation of plant species to different environments. Unexpectedly, no apparent latitudinal trends of LCV at community level were observed, although LCV at the species level clearly decreased with increasing latitude. Use efficiency of LCV (CUE, gC KJ-1), defined as the ratio of GPP to total LCV at the community level, varied quadratic with latitude and was lower in the middle latitudes. Climate (temperature and precipitation) may explain 52.9% of the variation in spatial patterns of CUE, which was positively correlated with aridity. Our findings are the first large-scale report of the latitudinal patterns of LCV in forests at the species, plant functional group, and community levels and provide new insights into the relationship between LCV and ecosystem functions in forest communities.

  15. Leaf Caloric Value from Tropical to Cold-Temperate Forests: Latitudinal Patterns and Linkage to Productivity

    PubMed Central

    Song, Guangyan; Hou, Jihua; Li, Ying; Zhang, Jiahui; He, Nianpeng

    2016-01-01

    Leaf caloric value (LCV) reflects the capacity of a leaf to fix and accumulate solar energy through photosynthesis. We systematically investigated the LCV of 745 plant species in 9 forests, representing a range of tropical to cold-temperate forests along the 4700-km North-South Transect of Eastern China. The goals were to explore the latitudinal patterns of LCV at the levels of species, plant functional group, and community and to establish the relationship between LCV and gross primary productivity (GPP). Our results showed that LCV for all species ranged from 12.85 to 22.15 KJ g–1 with an average of 18.46 KJ g–1. Plant functional groups had a significant influence on LCV, with trees > shrubs > herbs, conifers > broadleaved trees, and evergreens > deciduous trees. The different values of LCV represented the long-term evolution and adaptation of plant species to different environments. Unexpectedly, no apparent latitudinal trends of LCV at community level were observed, although LCV at the species level clearly decreased with increasing latitude. Use efficiency of LCV (CUE, gC KJ–1), defined as the ratio of GPP to total LCV at the community level, varied quadratic with latitude and was lower in the middle latitudes. Climate (temperature and precipitation) may explain 52.9% of the variation in spatial patterns of CUE, which was positively correlated with aridity. Our findings are the first large-scale report of the latitudinal patterns of LCV in forests at the species, plant functional group, and community levels and provide new insights into the relationship between LCV and ecosystem functions in forest communities. PMID:27341474

  16. Estimates of global research productivity in virology.

    PubMed

    Falagas, Matthew E; Karavasiou, Antonia I; Bliziotis, Ioannis A

    2005-06-01

    The quantity and quality of published research in the field of Virology by different world regions was estimated in this study. Using the PubMed database, articles from journals included in the "Virology" category of the "Journal Citation Reports" database of the Institute for Scientific Information for the period 1995-2003 were retrieved. The world was divided into nine regions based on geographic, economic, and scientific criteria. Data on the country of origin of the research was available for 33,425 out of 33,712 articles (99.2% of all articles from the included journals). USA exceeds all other world regions in research production for the period studied (42% of total articles), with Western Europe ranking second (35.7%). The mean impact factor in articles published in Virology journals was highest for the USA (4.60), while it was 3.90 for Western Europe and 3.22 for the rest of the world (seven regions combined). USA and Canada ranked first in research productivity when both gross national income per capita (GNIPC) and population were taken into account. The results of this analysis show a distressing fact; the absolute and relative production of research in the field of Virology by the developing regions is very low, although viral diseases cause considerable morbidity and mortality in these areas. It is evident from this study that developing regions need more help from the developed regions to enhance research infrastructure.

  17. Total research productivity in a pathology discipline

    PubMed Central

    Wierzbicki, A S; Reynolds, T M

    2002-01-01

    Aims: To investigate the research productivity of all staff in chemical pathology. Methods: Chemical pathologists or biochemical scientists were identified from publicly available sources. All journals, their impact factors (IFs), and individual publications over the period of 1995 to 1999 were identified from electronic databases. Each publication was subclassified with respect to type of publication, number and position of author, and subspecialty to which the article referred. Results: Research output over the period comprised 6162 articles, originating from 1399 individuals, 264 of whom were medically qualified. Specialty initiated research accounted for 26% of the total publications and 80% of the research was performed in teaching hospitals. Research output was highly skewed because 49% of individuals published a letter or more, 20% published one original piece of research over five years, but only 4% were research active, as defined by one publication each year. International standard research, defined as one paper each year in journals with IF > 4, was achieved by 1% of the profession, mostly aged > 55 years. Skewed distributions of publication rates were found in all age deciles. The possession of higher research degrees correlated with higher output in all age deciles. Conclusions: Those working in chemical pathology are active in initiating and conducting research, although at a low level. Because longterm activity in research correlates with the possession of higher research degrees and the opportunity to carry out research from early in career pathways, priority should be given to encouraging research in training, given the small and ageing profile of international quality research in the profession in the UK. PMID:12101192

  18. Physical soil properties and slope treatments effects on hydraulic excavator productivity for forest road construction.

    PubMed

    Parsakho, Aidin; Hosseini, Seyed Ataollah; Jalilvand, Hamid; Lotfalian, Majid

    2008-06-01

    Effects of moisture, porosity and soil bulk density properties, grubbing time and terrain side slopes on pc 220 komatsu hydraulic excavator productivity were investigated in Miana forests road construction project which located in the northern forest of Iran. Soil moisture and porosity determined by samples were taken from undisturbed soil. The elements of daily works were measured with a digital stop watch and video camera in 14 observations (days). The road length and cross section profiles after each 20 m were selected to estimate earthworks volume. Results showed that the mean production rates for the pc 220 komatsu excavators were 60.13 m3 h(-1) and earthwork 14.76 m h(-1) when the mean depth of excavation or cutting was 4.27 m3 m(-1), respectively. There was no significant effects (p = 0.5288) from the slope classes' treatments on productivity, whereas grubbing time, soil moisture, bulk density and porosity had significantly affected on excavator earthworks volume (p < 0.0001). Clear difference was showed between the earthwork length by slope classes (p = 0.0060). Grubbing time (p = 0.2180), soil moisture (p = 0.1622), bulk density (p = 0.2490) and porosity (p = 0.2159) had no significant effect on the excavator earthworks length.

  19. Production of ectomycorrhizal mycelium peaks during canopy closure in Norway spruce forests.

    PubMed

    Wallander, Håkan; Johansson, Ulf; Sterkenburg, Erica; Brandström Durling, Mikael; Lindahl, Björn D

    2010-09-01

    *Here, species composition and biomass production of actively growing ectomycorrhizal (EM) mycelia were studied over the rotation period of managed Norway spruce (Picea abies) stands in south-western Sweden. *The EM mycelia were collected using ingrowth mesh bags incubated in the forest soil during one growing season. Fungal biomass was estimated by ergosterol analysis and the EM species were identified by 454 sequencing of internal transcribed spacer (ITS) amplicons. Nutrient availability and the fungal biomass in soil samples were also estimated. *Biomass production peaked in young stands (10-30 yr old) before the first thinning phase. Tylospora fibrillosa dominated the EM community, especially in these young stands, where it constituted 80% of the EM amplicons derived from the mesh bags. Species richness increased in older stands. *The establishment of EM mycelial networks in young Norway spruce stands requires large amounts of carbon, while much less is needed to sustain the EM community in older stands. The variation in EM biomass production over the rotation period has implications for carbon sequestration rates in forest soils.

  20. Modeling Forest Biomass and Productivity: Coupling Long-Term Inventory and G-LiHT Data

    NASA Astrophysics Data System (ADS)

    Babcock, C. R.; Finley, A.; Cook, B. D.

    2013-12-01

    To better understand how space-based light detection and ranging (LiDAR) and long-term inventory data can be used to map forest above-ground biomass (AGB), we propose and examine a novel modeling approach to improve AGB prediction and estimate productivity. For this analysis we use LiDAR data acquired from NASA Goddard's LiDAR, Hyper-spectral & Thermal (G-LiHT) imager and field inventory data from the Penobscot Experimental Forest (PEF) in Bradley, Maine. Uncertainties associated with plot locations, field inventory measurements, and LiDAR misregistration are always present when modeling these data. Rather than assuming these sources of error are negligible, we choose to account for these and other uncertainties by adopting a Bayesian modeling framework that will afford us the opportunity to specify complex and dynamic model parameter associations and propagate uncertainty through to prediction. Specifically, we specify a space-varying coefficients model to predict and map AGB alongside productivity. The proposed framework models productivity and AGB simultaneously. The proposed model also accommodates temporal misalignment between field measurements and remotely sensed data. Results show that the proposed model outperforms benchmark models in fit and predictive ability as indicated by significant reductions in model deviance information criterion (DIC) and root mean squared prediction error (RMSPE).

  1. Faculty Colleagueship Patterns and Research Productivity.

    ERIC Educational Resources Information Center

    Finkelstein, Martin

    The effect on productivity on different types of collegial interaction among faculty were studied with attention to institutional type, disciplinary affiliation, orientation to teaching versus research, and career age. Collegial interaction was defined in terms of the reciprocal fulfillment of needs or exchange of services that occur in the course…

  2. The productivity of primary care research networks.

    PubMed Central

    Griffiths, F; Wild, A; Harvey, J; Fenton, E

    2000-01-01

    Primary care research networks are being publicly funded in the United Kingdom to promote a culture of research and development in primary care. This paper discusses the organisational form of these networks and how their productivity can be evaluated, drawing on evidence from management science. An evaluation of a research network has to take account of the complexity of the organisation, the influence of its local context, and its stage of development. Output measures, such as number of research papers, and process measures, such as number of research meetings, may contribute to an evaluation. However, as networking relies on the development of informal, trust-based relationships, the quality of interactions within a network is of paramount importance for its success. Networks can audit and reflect on their success in promoting such relationships and a more formal qualitative evaluation by an independent observer can document their success to those responsible for funding. PMID:11141879

  3. Measuring the productivity of university research reactors

    SciTech Connect

    Voth, M.H.

    1989-11-01

    University Research Reactors (URRs) on 33 campuses in the United States provide valuable contributions to academic instruction and research programs. In most cases, there are no alternative diagnostic techniques to supplant the need for a reactor and associated facilities. Since URRs constitute a major financial commitment, it is important that they be operated in a productive manner. Productivity may be defined as the sum of new knowledge generated, existing knowledge transferred to others, and analytical services provided to assist in the generation of new knowledge; another definition of productivity is this sum expressed as a function of the cost incurred. In either case, a consistent measurement is difficult and more qualitative than quantitative. A uniform reporting system has been proposed that defines simplified categories through which meaningful comparisons can be performed.

  4. Comparing the Impacts of Forest Thinning and Mortality on Streamflow, Recharge, and Forest Productivity in a Semi-Arid Mountain Watershed

    NASA Astrophysics Data System (ADS)

    Dugger, A. L.; Tague, C.; Allen, C. D.; Ringler, T.

    2012-12-01

    Forested mountain systems across the Southwest U.S. are increasingly shaped by novel pressures, including artificially dense and continuous canopies due to fire suppression, warmer temperatures, more frequent drought periods, and increasing demands on downstream water supplies. Forest restoration through thinning and prescribed burns is currently underway in a number of watersheds across the region, bolstered by not only the fire risk abatement benefits but also the generally accepted premise that fewer trees lead to more streamflow. However, a recent study (Guardiola-Claramonte et al., 2011) found just the opposite, observing increases in streamflow after drought-induced vegetation die-off in a set of Southwest U.S. basins. In this study, we use a spatially distributed, processes-based, eco-hydrologic model (RHESSys) to simulate forest thinning and die-off in the Santa Fe Municipal Watershed in Northern New Mexico to compare impacts on hydrology. We vary the spatial distribution of thinning (by elevation and aspect), intensity of biomass removal, litter and debris management, and understory growth, and compare to simulated drought-induced mortality. Forest structural changes alter radiation and water movement in complex ways though variations in albedo, radiation attenuation, interception, evapotranspiration, and soil moisture storage. Using the model to track these processes, we compare changes in recharge, streamflow, and net primary productivity under thinning, mortality, and climate scenarios, and determine spatial scales (stand, hillslope, basin) at which changes are significant. Based on these findings, we present a systematic analysis of conditions that are likely to lead to significant increases or decreases in water yield and changes in forest vulnerability to drought stress. Our results highlight how direct human modifications to the landscape, through thinning, might alter warming and drought impacts, and consequences for forest health and water

  5. Coexistence in tropical forests through asynchronous variation in annual seed production.

    PubMed

    Usinowicz, Jacob; Wright, S Joseph; Ives, Anthony R

    2012-09-01

    The storage effect is a mechanism that can facilitate the coexistence of competing species through temporal fluctuations in reproductive output. Numerous natural systems have the prerequisites for the storage effect, yet it has rarely been quantitatively assessed. Here, we investigate the possible importance of the storage effect in explaining the coexistence of tree species in the diverse tropical forest on Barro Colorado Island, Panama. This tropical forest has been monitored for more than 20 years, and annual seed production is asynchronous among species, a primary requirement for the storage effect. We constructed a model of forest regeneration that includes species-specific recruitment through seed, sapling, and adult stages, and we parameterized the model using data for 28 species for which information is known about seedling germination and survival. Simulations of the model demonstrated that the storage effect alone can be a strong mechanism allowing long-term persistence of species. We also developed a metric to quantify the strength of the storage effect in a way comparable to classical resource partitioning. Applying this metric to seed production data from 108 species, the storage effect reduces the strength of pairwise interspecific competition to 11-43% of the strength of intraspecific competition, thereby demonstrating strong potential to facilitate coexistence. Finally, for a subset of 51 species whose phylogenetic relationships are known, we compared the strength of the storage effect between pairs of species to their phylogenetic similarity. The strength of the storage effect between closely related species was on average no different from distantly related species, implying that the storage effect can be important in promoting the coexistence of even closely related species.

  6. Forest response to elevated CO2 is conserved across a broad range of productivity.

    PubMed

    Norby, Richard J; Delucia, Evan H; Gielen, Birgit; Calfapietra, Carlo; Giardina, Christian P; King, John S; Ledford, Joanne; McCarthy, Heather R; Moore, David J P; Ceulemans, Reinhart; De Angelis, Paolo; Finzi, Adrien C; Karnosky, David F; Kubiske, Mark E; Lukac, Martin; Pregitzer, Kurt S; Scarascia-Mugnozza, Giuseppe E; Schlesinger, William H; Oren, Ram

    2005-12-13

    Climate change predictions derived from coupled carbon-climate models are highly dependent on assumptions about feedbacks between the biosphere and atmosphere. One critical feedback occurs if C uptake by the biosphere increases in response to the fossil-fuel driven increase in atmospheric [CO(2)] ("CO(2) fertilization"), thereby slowing the rate of increase in atmospheric [CO(2)]. Carbon exchanges between the terrestrial biosphere and atmosphere are often first represented in models as net primary productivity (NPP). However, the contribution of CO(2) fertilization to the future global C cycle has been uncertain, especially in forest ecosystems that dominate global NPP, and models that include a feedback between terrestrial biosphere metabolism and atmospheric [CO(2)] are poorly constrained by experimental evidence. We analyzed the response of NPP to elevated CO(2) ( approximately 550 ppm) in four free-air CO(2) enrichment experiments in forest stands. We show that the response of forest NPP to elevated [CO(2)] is highly conserved across a broad range of productivity, with a stimulation at the median of 23 +/- 2%. At low leaf area indices, a large portion of the response was attributable to increased light absorption, but as leaf area indices increased, the response to elevated [CO(2)] was wholly caused by increased light-use efficiency. The surprising consistency of response across diverse sites provides a benchmark to evaluate predictions of ecosystem and global models and allows us now to focus on unresolved questions about carbon partitioning and retention, and spatial variation in NPP response caused by availability of other growth limiting resources.

  7. Acacia koa forest classification and productivity assessment across environmental gradients in Hawaii using fine resolution remotely sensed imagery

    NASA Astrophysics Data System (ADS)

    Martinez Morales, R.; Idol, T.; Chen, Q.

    2009-05-01

    Koa (Acacia koa) is an important native tree species in Hawaii economically and ecologically. Different Acacia koa (koa) forest types are found across the elevation and rainfall gradients typical of the Hawaiian Islands. The purpose of this study was to develop methodologies to differentiate these forests and to assess indices and indicators of forest productivity across these gradients using fine resolution remotely sensed imagery. IKONOS satellite imagery was analyzed using advanced statistical modeling and compared to field measurements of productivity indices. The calculation of several vegetation indices that are commonly used in vegetation studies, allowed classification of various koa forest types into micro-regions in wet and dry locations across elevation gradients ranging from 300-850 m. Vegetation indices and image texture parameters strongly related to tree height, N, P and specific leaf area and less strongly with leaf area index and basal area across gradient sites. This allowed development of statistical models that can be used in the assessment of koa forest productivity indices at landscape and regional scales. This will also allow for the application of specific forest management strategies suitable to the environmental conditions and plant requirements for optimal tree growth in each micro-region.

  8. Remote sensing of net ecosystem productivity based on component spectrum and soil respiration observation in a boreal forest, interior Alaska

    NASA Astrophysics Data System (ADS)

    Kushida, Keiji; Kim, Yongwon; Tanaka, Noriyuki; Fukuda, Masami

    2004-03-01

    We built a remote-sensing method for determining leaf area index (LAI) and ground cover mosses/lichens in boreal forests by field component spectral observation and radiative transfer modeling based on the spectrum. The method was applied to evaluate annual net ecosystem productivity (NEP) distribution in a boreal forest, interior Alaska, by accounting for net primary productivity (NPP) of the vegetation compositions and soil respiration observation synchronized to the spectral observation. Spectral reflectance and soil respiration were observed in two 30-m × 30-m plots in black spruce stands, central Alaska. Spectral characteristics of the forest floor and the needle leaves were used as input parameters of a radiative transfer model to evaluate nadir reflectances of spruce communities in relation to varying upper layer LAI, forest floor bryophyte types, and leaf spectral characteristics. Using the relationship, we obtained LAI and bryophyte area ratios for each pixel that corresponds to spruce forest on Landsat ETM+ imagery. The LAI-NPP relationship of spruce forest was estimated from 's [1981] normal yield table data and specific leaf area, and NPP was calculated from LAI. Observations of daily respiration were extrapolated to annual timescales using soil temperature. On the basis of the annual soil respiration and NPP of the upper layer and forest floor, annual NEP geographical distribution in a recent normal year was estimated from remotely sensed LAI and forest floor bryophyte area ratios. The annually estimated NEP was 51 g C/m2/yr, which corresponds to the value (55 g C/m2/yr) for 150-year-old black spruce forest in the Boreal Ecosystem-Atmosphere Study (BOREAS) region, Canada.

  9. Climatically induced interannual variability in aboveground production in forest-tundra and northern taiga of central Siberia.

    PubMed

    Knorre, Anastasia A; Kirdyanov, Alexander V; Vaganov, Eugene A

    2006-02-01

    To investigate the variability of primary production of boreal forest ecosystems under the current climatic changes, we compared the dynamics of annual increments and productivity of the main components of plant community (trees, shrubs, mosses) at three sites in the north of Siberia (Russia). Annual radial growth of trees and shrubs was mostly defined by summer temperature regime (positive correlation), but climatic response of woody plants was species specific and depends on local conditions. Dynamics of annual increments of mosses were opposite to tree growth. The difference in climatic response of the different vegetation components of the forest ecosystems indicates that these components seem to be adapted to use climatic conditions during the short and severe northern summer, and decreasing in annual production of one component is usually combined with the increase of other component productivity. Average productivity in the northern forest ecosystems varies from 0.05 to 0.14 t ha(-1) year(-1) for trees, from 0.05 to 0.18 t ha(-1) year(-1) for shrubs and from 0.54 to 0.66 t ha(-1) year(-1) for mosses. Higher values of tree productivity combined with lower annual moss productivity were found in sites in northern taiga in comparison with forest-tundra. Different tendencies in the productivity of the dominant species from each vegetation level (trees, shrubs, mosses) were indicated for the last 10 years studied (1990-1999): while productivity of mosses is increasing, productivity of trees is decreasing, but there is no obvious trend in the productivity of shrubs. Our results show that in the long term, the main contribution to changes in annual biomass productivity in forest-tundra and northern taiga ecosystems under the predicted climatic changes will be determined by living ground cover.

  10. Controls on sediment production from unpaved forest roads in the Honna watershed, Canada

    NASA Astrophysics Data System (ADS)

    van Meerveld, Ilja; Baird, Elizabeth; Floyd, Bill

    2013-04-01

    Unpaved forest roads are common in many areas and have the potential to produce large amounts of sediment. Traffic on unpaved roads results in the breakdown of surface material and the upward forcing of fine-grained sediment from the road bed. This sediment is transported off the road during rainfall events because the infiltration capacity of roads is generally very low. When there is a high connectivity between the road and a stream, this sediment can be transported to the stream, impacting water quality and aquatic ecology. Despite an increasing number of studies quantifying sediment generation from unpaved roads, there is little agreement on the dominant controls and physical processes affecting the amount of sediment generated from forest roads. We did 24 rainfall simulation experiments on a 30 m forest road section in the Honna Watershed, Haida Gwaii, British Columbia, Canada to determine the controls on sediment generation, in particular the influence of rainfall intensity, rainfall amount, antecedent precipitation, traffic intensity, and truck speed. The 5-52 mm/hr rainfall experiments took place during active hauling between September and November 2009. The results from the experiments showed that precipitation intensity controlled the amount of sediment generated from the road. The number of passages of loaded logging trucks during an experiment was the second most dominant control. Each loaded truck passage resulted in a new sediment pulse, which persisted for 30 minutes during low rainfall intensity events and for shorter times during higher rainfall intensity events. Eight small scale (4-19 mm/hr) rainfall simulation experiments showed that the spatial variability in sediment production from forests roads is high, even for sections of the same road. Steady state sediment concentrations were, however, similar for the different locations. Upscaling of the results from the large scale rainfall simulation experiments and turbidity measurements in the Honna

  11. Can extractive reserves save the rain forest: A ecological and socioeconomic comparison of non-timber forest product extraction systems in Peten, Guatemala, and West Kalimantan, Indonesia

    SciTech Connect

    Salafsky, N.; Dugelby, B.L.; Terborgh, J.W.

    1992-04-01

    Extractive reserves in tropical rain forests, in which only non-timber products are harvested, have been heralded by some conservationists as a means of maintaining biodiversity while providing income for local people. The study of extraction systems in Peten, Guatemala, and in West Kalimantan, Indonesia, leads to a more tempered conclusion, for while the Peten program was quite successful, the Kalimantan program was not. The study finds the success of an extractive reserve to be contingent on: (1) ecological conditions, and (2) socioeconomic and political factors. Although the study focuses on market-oriented extractive reserves, many of the issues discussed apply as well to other land uses such as the collection of non-timber forest products for household consumption or small-scale timber extraction.

  12. Production possibility frontiers and socioecological tradeoffs for restoration of fire adapted forests.

    PubMed

    Ager, Alan A; Day, Michelle A; Vogler, Kevin

    2016-07-01

    We used spatial optimization to analyze alternative restoration scenarios and quantify tradeoffs for a large, multifaceted restoration program to restore resiliency to forest landscapes in the western US. We specifically examined tradeoffs between provisional ecosystem services, fire protection, and the amelioration of key ecological stressors. The results revealed that attainment of multiple restoration objectives was constrained due to the joint spatial patterns of ecological conditions and socioeconomic values. We also found that current restoration projects are substantially suboptimal, perhaps the result of compromises in the collaborative planning process used by federal planners, or operational constraints on forest management activities. The juxtaposition of ecological settings with human values generated sharp tradeoffs, especially with respect to community wildfire protection versus generating revenue to support restoration and fire protection activities. The analysis and methods can be leveraged by ongoing restoration programs in many ways including: 1) integrated prioritization of restoration activities at multiple scales on public and adjoining private lands, 2) identification and mapping of conflicts between ecological restoration and socioeconomic objectives, 3) measuring the efficiency of ongoing restoration projects compared to the optimal production possibility frontier, 4) consideration of fire transmission among public and private land parcels as a prioritization metric, and 5) finding socially optimal regions along the production frontier as part of collaborative restoration planning.

  13. Production of alkaline cellulase by fungi isolated from an undisturbed rain forest of peru.

    PubMed

    Vega, Karin; Villena, Gretty K; Sarmiento, Victor H; Ludeña, Yvette; Vera, Nadia; Gutiérrez-Correa, Marcel

    2012-01-01

    Alkaline cellulase producing fungi were isolated from soils of an undisturbed rain forest of Peru. The soil dilution plate method was used for the enumeration and isolation of fast growing cellulolytic fungi on an enriched selective medium. Eleven out of 50 different morphological colonies were finally selected by using the plate clearing assay with CMC as substrate at different pH values. All 11 strains produced cellulases in liquid culture with activities at alkaline pH values without an apparent decrease of them indicating that they are true alkaline cellulase producers. Aspergillus sp. LM-HP32, Penicillium sp. LM-HP33, and Penicillium sp. LM-HP37 were the best producers of FP cellulase (>3 U mL(-1)) with higher specific productivities (>30 U g(-1) h(-1)). Three strains have been found suitable for developing processes for alkaline cellulase production. Soils from Amazonian rain forests are good sources of industrial fungi with particular characteristics. The results of the present study are of commercial and biological interest. Alkaline cellulases may be used in the polishing and washing of denim processing of the textile industry.

  14. Soil Macroinvertebrate Communities Across a Productivity Gradient in Deciduous Forests of Eastern North America

    DOE PAGES

    Wenk, Evelyn S.; Callaham, Mac A.; O'Brien, Joseph J.; ...

    2016-03-01

    We describe how, within the temperate, deciduous forests of the eastern US, diverse soil-fauna communities are structured by a combination of environmental gradients and interactions with other biota. The introduction of non-native soil taxa has altered communities and soil processes, and adds another degree of variability to these systems. We sampled soil macroinvertebrate abundance from forested sites in Missouri (MO), Michigan (MI), Massachusetts (MA), and New Hampshire (NH), with the objective of comparing community assemblages and evaluating the role of invasive earthworms along the temperature—productivity gradient represented by the sites. The primary detritivores encountered were earthworms and millipedes. Earthworms weremore » collected only in MO and MI, and at much greater density in MO. Millipedes were found at every site except in MO, and at their highest mean density in NH. Warmer temperatures, higher litter productivity, and low Oa horizon depth (as found in MO) were correlated with high earthworm activity. Oa horizon depth was the greatest in NH, where the macroinvertebrate community was dominated (in terms of abundance) by predators and herbivores, not detritivores. Our results are suggestive of, and congruent with, the concept of earthworms as ecosystem engineers, as we found that the presence of non-native earthworm species was associated with significant differences in soil characteristics such as apparent rapid decomposition rates and reduced carbon storage in the Oa horizon.« less

  15. Soil Macroinvertebrate Communities Across a Productivity Gradient in Deciduous Forests of Eastern North America

    SciTech Connect

    Wenk, Evelyn S.; Callaham, Mac A.; O'Brien, Joseph J.; Hanson, Paul J.

    2016-03-01

    We describe how, within the temperate, deciduous forests of the eastern US, diverse soil-fauna communities are structured by a combination of environmental gradients and interactions with other biota. The introduction of non-native soil taxa has altered communities and soil processes, and adds another degree of variability to these systems. We sampled soil macroinvertebrate abundance from forested sites in Missouri (MO), Michigan (MI), Massachusetts (MA), and New Hampshire (NH), with the objective of comparing community assemblages and evaluating the role of invasive earthworms along the temperature—productivity gradient represented by the sites. The primary detritivores encountered were earthworms and millipedes. Earthworms were collected only in MO and MI, and at much greater density in MO. Millipedes were found at every site except in MO, and at their highest mean density in NH. Warmer temperatures, higher litter productivity, and low Oa horizon depth (as found in MO) were correlated with high earthworm activity. Oa horizon depth was the greatest in NH, where the macroinvertebrate community was dominated (in terms of abundance) by predators and herbivores, not detritivores. Our results are suggestive of, and congruent with, the concept of earthworms as ecosystem engineers, as we found that the presence of non-native earthworm species was associated with significant differences in soil characteristics such as apparent rapid decomposition rates and reduced carbon storage in the Oa horizon.

  16. Climatic Changes in the East-European Forest-Steppe and Effects on Scots Pine Productivity

    NASA Astrophysics Data System (ADS)

    Matveev, S. M.; Chendev, Yu. G.; Lupo, A. R.; Hubbart, J. A.; Timashchuk, D. A.

    2017-01-01

    Climate change during the 20th and early 21st centuries in the transitional zone between forests and grasslands at the center of the East-European Plain (Voronezh oblast) was determined by examining climate trends and variability using tree ring radial increment data as representative of productivity. An increase in atmospheric moisture for the warm period of the year (May-September) since 1890s, and mean annual temperatures since the 1950s was identified. During the same time period, there was a marked increase in amplitude of the annual variations for temperature and precipitation. Study results revealed trends, variability in the climatic indices, and corresponding radial wood increment for the regional stands of Pinus sylvestris L. These fluctuations are consistent with 10-12-years Schwabe-Wolf, 22-years Hale, and the 32-36-years Bruckner Solar Cycles. There was an additional relationship found between high-frequency (short-period) climate fluctuations, lasting for about three years, and 70-90-years fluctuations of the moisture regime in the study region corresponding to longer cycles. The results of this study can help guide management decisions in the study region and elsewhere, especially where climate change induced alterations to the state and productivity of forest ecosystems and associated natural resource commodities are of growing concern.

  17. Relationships between net primary productivity and stand age for several forest types and their influence on China's carbon balance.

    PubMed

    Wang, Shaoqiang; Zhou, Lei; Chen, Jingming; Ju, Weimin; Feng, Xianfeng; Wu, Weixing

    2011-06-01

    Affected by natural and anthropogenic disturbances such as forest fires, insect-induced mortality and harvesting, forest stand age plays an important role in determining the distribution of carbon pools and fluxes in a variety of forest ecosystems. An improved understanding of the relationship between net primary productivity (NPP) and stand age (i.e., age-related increase and decline in forest productivity) is essential for the simulation and prediction of the global carbon cycle at annual, decadal, centurial, or even longer temporal scales. In this paper, we developed functions describing the relationship between national mean NPP and stand age using stand age information derived from forest inventory data and NPP simulated by the BEPS (Boreal Ecosystem Productivity Simulator) model in 2001. Due to differences in ecobiophysical characteristics of different forest types, NPP-age equations were developed for five typical forest ecosystems in China (deciduous needleleaf forest (DNF), evergreen needleleaf forest in tropic and subtropical zones (ENF-S), deciduous broadleaf forest (DBF), evergreen broadleaf forest (EBF), and mixed broadleaf forest (MBF)). For DNF, ENF-S, EBF, and MBF, changes in NPP with age were well fitted with a common non-linear function, with R(2) values equal to 0.90, 0.75, 0.66, and 0.67, respectively. In contrast, a second order polynomial was best suitable for simulating the change of NPP for DBF, with an R(2) value of 0.79. The timing and magnitude of the maximum NPP varied with forest types. DNF, EBF, and MBF reached the peak NPP at the age of 54, 40, and 32 years, respectively, while the NPP of ENF-S maximizes at the age of 13 years. The highest NPP of DBF appeared at 122 years. NPP was generally lower in older stands with the exception of DBF, and this particular finding runs counter to the paradigm of age-related decline in forest growth. Evaluation based on measurements of NPP and stand age at the plot-level demonstrates the reliability

  18. Advances of air pollution science: from forest decline to multiple-stress effects on forest ecosystem services.

    PubMed

    Paoletti, E; Schaub, M; Matyssek, R; Wieser, G; Augustaitis, A; Bastrup-Birk, A M; Bytnerowicz, A; Günthardt-Goerg, M S; Müller-Starck, G; Serengil, Y

    2010-06-01

    Over the past 20 years, the focus of forest science on air pollution has moved from forest decline to a holistic framework of forest health, and from the effects on forest production to the ecosystem services provided by forest ecosystems. Hence, future research should focus on the interacting factorial impacts and resulting antagonistic and synergistic responses of forest trees and ecosystems. The synergistic effects of air pollution and climatic changes, in particular elevated ozone, altered nitrogen, carbon and water availability, must be key issues for research. Present evidence suggests air pollution will become increasingly harmful to forests under climate change, which requires integration amongst various stressors (abiotic and biotic factors, including competition, parasites and fire), effects on forest services (production, biodiversity protection, soil protection, sustained water balance, socio-economical relevance) and assessment approaches (research, monitoring, modeling) to be fostered.

  19. Calculating net primary productivity of forest ecosystem with G4M model: case study on South Korea

    NASA Astrophysics Data System (ADS)

    Sung, S.; Forsell, N.; Kindermann, G.; Lee, D. K.

    2015-12-01

    Net primary productivity (NPP) is considered as an important indicator for forest ecosystem since the role of forest is highlighted as a stepping stone for mitigating climate change. Especially rapidly urbanizing countries which have high carbon dioxide emission have large interest in calculating forest NPP under climate change. Also maximizing carbon sequestration in forest sector has became a global goal to minimize the impacts of climate change. Therefore, the objective of this research is estimating carbon stock change under the different climate change scenarios by using G4M (Global Forestry Model) model in South Korea. We analyzed four climate change scenarios in different Representative Concentration Pathway (RCP). In this study we used higher resolution data (1kmx1km) to produce precise estimation on NPP from regionalized four climate change scenarios in G4M model. Finally, we set up other environmental variables for G4M such as water holding capacity, soil type and elevation. As a result of this study, temperature showed significant trend during 2011 to 2100. Average annual temperature increased more than 5℃ in RCP 8.5 scenario while 1℃ increased in RCP 2.6 scenario. Each standard deviation of the annual average temperature showed similar trend. Average annual precipitation showed similarity within four scenarios. However the standard deviation of average annual precipitation is higher in RCP8.5 scenario which indicates the ranges of precipitation is wider in RCP8.5 scenario. These results present that climate indicators such as temperature and precipitation have uncertainties in climate change scenarios. NPP has changed from 5-13tC/ha/year in RCP2.6 scenario to 9-21 tC/ha/year in RCP8.5 scenario in 2100. In addition the spatial distribution of NPP presented different trend among the scenarios. In conclusion we calculated differences in temperature and precipitation and NPP change in different climate change scenarios. This study can be applied for

  20. The production of β-glucosidases by Fusarium proliferatum NBRC109045 isolated from Vietnamese forest

    PubMed Central

    2012-01-01

    Fusarium proliferatum NBRC109045 is a filamentous fungus isolated from Vietnamese forest due to high production of β-glucosidases. Production of the enzyme was studied on varied carbon source based mediums. The highest activity was obtained in medium containing 1% corn stover + 1% wheat bran (3.31 ± 0.14 U/ml). It is interesting to note that glucose (0.69 ± 0.02 U/ml) gave higher activity and just followed by cellobiose among the di- and mono-saccharides, which is generally regarded as a universal repressor of hydrolases. We improved the zymogram method to prove that in response to various carbon sources, F. proliferatum could express various β-glucosidases. One of the β-glucosidases produced by F. proliferatum growing in corn stover + wheat bran based medium was partially purified and proved to have high catalytic ability. PMID:22974424

  1. Timber production assessment of a plantation forest: An integrated framework with field-based inventory, multi-source remote sensing data and forest management history

    NASA Astrophysics Data System (ADS)

    Gao, Tian; Zhu, Jiaojun; Deng, Songqiu; Zheng, Xiao; Zhang, Jinxin; Shang, Guiduo; Huang, Liyan

    2016-10-01

    Timber production is the purpose for managing plantation forests, and its spatial and quantitative information is critical for advising management strategies. Previous studies have focused on growing stock volume (GSV), which represents the current potential of timber production, yet few studies have investigated historical process-harvested timber. This resulted in a gap in a synthetical ecosystem service assessment of timber production. In this paper, we established a Management Process-based Timber production (MPT) framework to integrate the current GSV and the harvested timber derived from historical logging regimes, trying to synthetically assess timber production for a historical period. In the MPT framework, age-class and current GSV determine the times of historical thinning and the corresponding harvested timber, by using a "space-for-time" substitution. The total timber production can be estimated by the historical harvested timber in each thinning and the current GSV. To test this MPT framework, an empirical study on a larch plantation (LP) with area of 43,946 ha was conducted in North China for a period from 1962 to 2010. Field-based inventory data was integrated with ALOS PALSAR (Advanced Land-Observing Satellite Phased Array L-band Synthetic Aperture Radar) and Landsat-8 OLI (Operational Land Imager) data for estimating the age-class and current GSV of LP. The random forest model with PALSAR backscatter intensity channels and OLI bands as input predictive variables yielded an accuracy of 67.9% with a Kappa coefficient of 0.59 for age-class classification. The regression model using PALSAR data produced a root mean square error (RMSE) of 36.5 m3 ha-1. The total timber production of LP was estimated to be 7.27 × 106 m3, with 4.87 × 106 m3 in current GSV and 2.40 × 106 m3 in harvested timber through historical thinning. The historical process-harvested timber accounts to 33.0% of the total timber production, which component has been neglected in the

  2. Sequential parametric optimization of methane production from different sources of forest raw material

    PubMed Central

    Matsakas, Leonidas; Rova, Ulrika; Christakopoulos, Paul

    2015-01-01

    The increase in environmental problems and the shortage of fossil fuels have led to the need for action in the development of sustainable and renewable fuels. Methane is produced through anaerobic digestion of organic materials and is a biofuel with very promising characteristics. The success in using methane as a biofuel has resulted in the operation of several commercial-scale plants and the need to exploit novel materials to be used. Forest biomass can serve as an excellent candidate for use as raw material for anaerobic digestion. During this work, both hardwood and softwood species—which are representative of the forests of Sweden—were used for the production of methane. Initially, when untreated forest materials were used for the anaerobic digestion, the yields obtained were very low, even with the addition of enzymes, reaching a maximum of only 40 mL CH4/g VS when birch was used. When hydrothermal pretreatment was applied, the enzymatic digestibility improved up to 6.7 times relative to that without pretreatment, and the yield of methane reached up to 254 mL CH4/g VS. Then the effect of chemical/enzymatic detoxification was examined, where laccase treatment improved the methane yield from the more harshly pretreated materials while it had no effect on the more mildly pretreated material. Finally, addition of cellulolytic enzymes during the digestion improved the methane yields from spruce and pine, whereas for birch separate saccharification was more beneficial. To achieve high yields in spruce 30 filter paper units (FPU)/g was necessary, whereas 15 FPU/g was enough when pine and birch were used. During this work, the highest methane yields obtained from pine and birch were 179.9 mL CH4/g VS and 304.8 mL CH4/g VS, respectively. For mildly and severely pretreated spruce, the methane yields reached 259.4 mL CH4/g VS and 276.3 mL CH4/g VS, respectively. We have shown that forest material can serve as raw material for efficient production of methane. The

  3. Considerations for Sustainable Biomass Production in Quercus-Dominated Forest Ecosystems

    NASA Astrophysics Data System (ADS)

    Bruckman, Viktor; Yan, Shuai; Hochbichler, Eduard

    2013-04-01

    Our current energy system is mainly based on carbon (C) intensive metabolisms, resulting in great effects on the earth's biosphere. The majority of the energy sources are fossil (crude oil, coal, natural gas) and release CO2 in the combustion (oxidation) process which takes place during utilization of the energy. C released to the atmosphere was once sequestered by biomass over a time span of millions of years and is now being released back into the atmosphere within a period of just decades. In the context of green and CO2 neutral Energy, there is an on-going debate regarding the potentials of obtaining biomass from forests on multiple scales, from stand to international levels. Especially in the context of energy, it is highlighted that biomass is an entirely CO2 neutral feedstock since the carbon stored in wood originates from the atmospheric CO2 pool and it was taken up during plant growth. It needs systems approaches in order to justify this statement and ensure sustainability covering the whole life-cycle from biomass production to (bio)energy consumption. There are a number of Quercus woodland management systems focussing solely on woody biomass production for energetic utilization or a combination with traditional forestry and high quality timber production for trades and industry. They have often developed regionally as a consequence of specific demands and local production capacities, which are mainly driven by environmental factors such as climate and soil properties. We assessed the nutritional status of a common Quercus-dominated forest ecosystem in northern Austria, where we compared biomass- with belowground C and nutrient pools in order to identify potential site limits if the management shifts towards systems with a higher level of nutrient extraction. Heterogeneity of soils, and soil processes are considered, as well as other, growth-limiting factors (e.g. precipitation) and species-specific metabolisms and element translocation.

  4. Sustainability Impact Assessment of two forest-based bioenergy production systems related to mitigation and adaption to Climate Change

    NASA Astrophysics Data System (ADS)

    Gartzia-Bengoetxea, Nahia; Arias-González, Ander; Tuomasjukka, Diana

    2016-04-01

    New forest management strategies are necessary to resist and adapt to Climate Change (CC) and to maintain ecosystem functions such as forest productivity, water storage and biomass production. The increased use of forest-based biomass for energy generation as well as the application of combustion or pyrolysis co-products such as ash or biochar back into forest soils is being suggested as a CC mitigation and adaptation strategy while trying to fulfil the targets of both: (i) Europe 2020 growth strategy in relation to CC and energy sustainability and (ii) EU Action Plan for the Circular Economy. The energy stored in harvested biomass can be released through combustion and used for energy generation to enable national energy security (reduced oil dependence) and the substitution of fossil fuel by renewable biomass can decrease the emission of greenhouse gases.In the end, the wood-ash produced in the process can return to the forest soil to replace the nutrients exported by harvesting. Another way to use biomass in this green circular framework is to pyrolyse it. Pyrolysis of the biomass produce a carbon-rich product (biochar) that can increase carbon sequestration in the soils and liquid and gas co-products of biomass pyrolysis can be used for energy generation or other fuel use thereby offsetting fossil fuel consumption and so avoiding greenhouse gas emissions. Both biomass based energy systems differ in the amount of energy produced, in the co-product (biochar or wood ash) returned to the field, and in societal impacts they have. The Tool for Sustainability Impact Assessment (ToSIA) was used for modelling both energy production systems. ToSIA integrates several different methods, and allows a quantification and objective comparison of economic, environmental and social impacts in a sustainability impact assessment for different decision alternatives/scenarios. We will interpret the results in order to support the bioenergy planning in temperate forests under the

  5. Quantifying canopy complexity and effects on productivity and resilience in late-successional hemlock-hardwood forests.

    PubMed

    Fahey, Robert T; Fotis, Alexander T; Woods, Kerry D

    2015-04-01

    The regrowing forests of eastern North America have been an important global C sink over the past 100+ years, but many are now transitioning into late succession. The consequences of this transition are unclear due to uncertainty around the C dynamics of old- growth forests. Canopy structural complexity (CSC) has been shown to be an important source of variability in C dynamics in younger forests (e.g., in productivity and resilience to disturbance), but its role in late-successional forests has not been widely addressed. We investigated patterns of CSC in two old-growth forest landscapes in the Upper Peninsula of Michigan, USA, to assess factors associated with CSC and its influence on productivity and disturbance resilience (to moderate-severity windstorm). CSC was quantified using a portable below-canopy LiDAR (PCL) system in 65 plots that also had long-term (50-70+ years). inventory data, which were used to quantify aboveground net primary productivity (ANPP), disturbance history, and stand characteristics. We found high and variable CSC relative to younger forests across a suite of PCL-derived metrics. Variation in CSC was driven by species composition and size structure, rather than disturbance history or site characteristics. Recent moderate severity wind disturbance decreased plot-scale CSC, but increased stand-scale variation in CSC. The strong positive correlation between CSC and productivity illustrated in younger forests was not present in undisturbed portions of these late-successional ecosystems. Moderate severity disturbance appeared to reestablish the positive link between CSC and productivity, but this relationship was scale and severity dependent. A positive CSC-productivity relationship was evident at the plot scale with low-severity, dispersed disturbance, but only at a patch scale in more severely disturbed areas. CSC does not appear to strongly correlate With variation in productivity in undisturbed old-growth forests, but may play a very

  6. Research effort aims at floating production technology

    SciTech Connect

    Not Available

    1992-08-17

    This paper reports that a 3 year research and development program on floating production systems (FPS), instigated by the Royal Norwegian Council for Scientific and Industrial Research (NTNF), has refined and qualified technologies for North Sea and arctic conditions. The FPS 2000 program, which cost 58 million kroner ($10 million), concentrated mainly on mooring systems and pipeline technology, along with new system concepts and cost reduction measures. More than 30 projects have been completed within the scheme. The anchoring and positioning project concentrates on developing methods for simulating behavior of mooring systems for large volume structures in deep water. It also seeks ways to determine efficiency of dynamic positioning thrusters under extreme conditions.

  7. An optimal proportion of mixing broad-leaved forest for enhancing the effective productivity of moso bamboo

    PubMed Central

    Cheng, Xiao-Fei; Shi, Pei-Jian; Hui, Cang; Wang, Fu-Sheng; Liu, Guo-Hua; Li, Bai-Lian

    2015-01-01

    Moso bamboos (Phyllostachys edulis) are important forestry plants in southern China, with substantial roles to play in regional economic and ecological systems. Mixing broad-leaved forests and moso bamboos is a common management practice in China, and it is fundamental to elucidate the interactions between broad-leaved trees and moso bamboos for ensuring the sustainable provision of ecosystem services. We examine how the proportion of broad-leaved forest in a mixed managed zone, topology, and soil profile affects the effective productivity of moso bamboos (i.e., those with significant economic value), using linear regression and generalized additive models. Bamboo's diameter at breast height follows a Weibull distribution. The importance of these variables to bamboo productivity is, respectively, slope (25.9%), the proportion of broad-leaved forest (24.8%), elevation (23.3%), gravel content by volume (16.6%), slope location (8.3%), and soil layer thickness (1.2%). Highest productivity is found on the 25° slope, with a 600-m elevation, and 30% broad-leaved forest. As such, broad-leaved forest in the upper slope can have a strong influence on the effective productivity of moso bamboo, ranking only after slope and before elevation. These factors can be considered in future management practice. PMID:25937902

  8. Humus layer is the main locus of secondary SO4 production in boreal forests

    NASA Astrophysics Data System (ADS)

    Houle, Daniel; Marty, Charles; Duchesne, Louis; Gagnon, Christian

    2014-02-01

    Identifying the sources of S exported from catchments and the reactivity of the large soil organic S pool is crucial to understand the mid- or long-term response of forested catchments to decreasing atmospheric S deposition and global warming. Sulfur fluxes as well as S and O isotopes of SO4 were measured in precipitation, throughfall, soil solutions and streams at two boreal forest catchments respectively dominated by black spruce (BS) and balsam fir (BF) in Quebec, Canada. Overall, δ34S-SO4 signature showed relatively small variations among various solution types. However, at both sites, δ18O-SO4 in precipitation (averages of 10.5-11.1‰) was decreased by 3.5-3.6‰ in throughfall because of the production of secondary SO4 through oxidation of SO2 deposited on the canopy. Throughfall δ18O-SO4 was decreased by a further 5.4-6.6‰ in the solution leaving the humus layer which was attributed to the production of secondary SO4 under the action of soil microorganisms through the oxidation of organic S during which the S atom acquired O from water and gaseous O2 present in the soil. A mixing equation based on known isotopic signature of each source suggested that ˜67-81% of the S-SO4 leaving the catchments had interacted with the canopy and the humus layer. The stability of δ18O-SO4 in the mineral soil solution and in the stream of both sites, suggests that SO4 does not undergo reduction-oxidation cycles after its passage through the humus layer. Despite its huge size, the organic S reservoir within the mineral soil would be largely inert. Given the chemical nature of SO4 transformation in the canopy, the humus layer would be responsible for nearly 100% of the biological production of secondary SO4 in the whole watershed at both sites. Taking into account the substantial production of dissolved organic S in the humus layer further emphasizes the crucial importance of the latter in the S cycling of boreal forests.

  9. Carbon cycling and net ecosystem production at an early stage of secondary succession in an abandoned coppice forest.

    PubMed

    Ohtsuka, Toshiyuki; Shizu, Yoko; Nishiwaki, Ai; Yashiro, Yuichiro; Koizumi, Hiroshi

    2010-07-01

    Secondary mixed forests are one of the dominant forest cover types in human-dominated temperate regions. However, our understanding of how secondary succession affects carbon cycling and carbon sequestration in these ecosystems is limited. We studied carbon cycling and net ecosystem production (NEP) over 4 years (2004-2008) in a cool-temperate deciduous forest at an early stage of secondary succession (18 years after clear-cutting). Net primary production of the 18-year-old forest in this study was 5.2 tC ha(-1 )year(-1), including below-ground coarse roots; this was partitioned into 2.5 tC ha(-1 )year(-1) biomass increment, 1.6 tC ha(-1 )year(-1) foliage litter, and 1.0 tC ha(-1 )year(-1) other woody detritus. The total amount of annual soil surface CO(2) efflux was 6.8 tC ha(-1 )year(-1), which included root respiration (1.9 tC ha(-1 )year(-1)) and heterotrophic respiration (RH) from soils (4.9 tC ha(-1 )year(-1)). The 18-year forest at this study site exhibited a great increase in biomass pool as a result of considerable total tree growth and low mortality of tree stems. In contrast, the soil organic matter (SOM) pool decreased markedly (-1.6 tC ha(-1 )year(-1)), although further study of below-ground detritus production and RH of SOM decomposition is needed. This young 18-year forest was a weak carbon sink (0.9 tC ha(-1 )year(-1)) at this stage of secondary succession. The NEP of this 18-year forest is likely to increase gradually because biomass increases with tree growth and with the improvement of the SOM pool through increasing litter and dead wood production with stand development.

  10. Simulating effects of fire disturbance and climate change on boreal forest productivity and evapotranspiration.

    PubMed

    Kang, Sinkyu; Kimball, John S; Running, Steven W

    2006-06-01

    We used a terrestrial ecosystem process model, BIOME-BGC, to investigate historical climate change and fire disturbance effects on regional carbon and water budgets within a 357,500 km(2) portion of the Canadian boreal forest. Historical patterns of increasing atmospheric CO2, climate change, and regional fire activity were used as model drivers to evaluate the relative effects of these impacts to spatial patterns and temporal trends in forest net primary production (NPP) and evapotranspiration (ET). Historical trends of increasing atmospheric CO2 resulted in overall 13% and 5% increases in annual NPP and ET from 1994 to 1996, respectively. NPP was found to be relatively sensitive to changes in air temperature (T(a)), while ET was more sensitive to precipitation (P) change within the ranges of observed climate variability (e.g., +/-2 degrees C for T(a) and +/-20% for P). In addition, the potential effect of climate change related warming on NPP is exacerbated or offset depending on whether these changes are accompanied by respective decreases or increases in precipitation. Historical fire activity generally resulted in reductions of both NPP and ET, which consumed an average of approximately 6% of annual NPP from 1959 to 1996. Areas currently occupied by dry conifer forests were found to be subject to more frequent fire activity, which consumed approximately 8% of annual NPP. The results of this study show that the North American boreal ecosystem is sensitive to historical patterns of increasing atmospheric CO2, climate change and regional fire activity. The relative impacts of these disturbances on NPP and ET interact in complex ways and are spatially variable depending on regional land cover and climate gradients.

  11. Worldwide research productivity in critical care medicine

    PubMed Central

    Michalopoulos, Argyris; Bliziotis, Ioannis A; Rizos, Michael; Falagas, Matthew E

    2005-01-01

    Introduction The number of publications and the impact factor of journals are accepted estimates of the quantity and quality of research productivity. The objective of the present study was to assess the worldwide scientific contribution in the field of critical care medicine. Method All research studies published between 1995 and 2003 in medical journals that were listed in the 2003 Science Citation Index (SCI®) of Journal Citation Reports under the subheading 'critical care' and also indexed in the PubMed database were reviewed in order to identify their geographical origin. Results Of 22,976 critical care publications in 14 medical journals, 17,630 originated from Western Europe and the USA (76.7%). A significant increase in the number of publications originated from Western European countries during the last 5 years of the study period was noticed. Scientific publications in critical care medicine increased significantly (25%) from 1995 to 2003, which was accompanied by an increase in the impact factor of the corresponding journals (47.4%). Canada and Japan had the better performance, based on the impact factor of journals. Conclusion Significant scientific progress in critical care research took place during the period of study (1995–2003). Leaders of research productivity (in terms of absolute numbers) were Western Europe and the USA. Publications originating from Western European countries increased significantly in quantity and quality over the study period. Articles originating from Canada, Japan, and the USA had the highest mean impact factor.. Canada was the leader in productivity when adjustments for gross domestic product and population were made. PMID:15987399

  12. Productivity Research and Development Planning Workshop.

    DTIC Science & Technology

    1986-03-01

    Force Institute of Technology (AFIT), Leadership and Management Development Center (LMDC), Army Research Institute (ARI), and the Navy Personnel...Lloyd Woodman Leadership and Management Development Center 1555 Quality Circles Dr. Bob Steel Air Force Institute of Technology 1620 NPRDC...is that it is easier to think about productivity in orthodox or conventional terms than in the sense of weapons systems and technology . People plus

  13. Chimpanzee responses to researchers in a disturbed forest-farm mosaic at Bulindi, western Uganda.

    PubMed

    McLennan, Matthew R; Hill, Catherine M

    2010-09-01

    We describe the behavior of a previously unstudied community of wild chimpanzees during opportunistic encounters with researchers in an unprotected forest-farm mosaic at Bulindi, Uganda. Data were collected during 115 encounters between May 2006 and January 2008. Individual responses were recorded during the first minute of visual contact. The most common responses were "ignore" for arboreal chimpanzees and "monitor" for terrestrial individuals. Chimpanzees rarely responded with "flight". Adult males were seen disproportionately often relative to adult females, and accounted for 90% of individual responses recorded for terrestrial animals. Entire encounters were also categorized based on the predominant response of the chimpanzee party to researcher proximity. The most frequent encounter type was "ignore" (36%), followed by "monitor" (21%), "intimidation" (18%) and "stealthy retreat" (18%). "Intimidation" encounters occurred when chimpanzees were contacted in dense forest where visibility was low, provoking intense alarm and agitation. Adult males occasionally acted together to repel researchers through aggressive mobbing and pursuit. Chimpanzee behavior during encounters reflects the familiar yet frequently agonistic relationship between apes and local people at Bulindi. The chimpanzees are not hunted but experience high levels of harassment from villagers. Human-directed aggression by chimpanzees may represent a strategy to accommodate regular disruptions to foraging effort arising from competitive encounters with people both in and outside forest. Average encounter duration and proportion of encounters categorized as "ignore" increased over time, whereas "intimidation" encounters decreased, indicating some habituation occurred during the study. Ecotourism aimed at promoting tolerance of wildlife through local revenue generation is one possible strategy for conserving great apes on public or private land. However, the data imply that habituating chimpanzees for

  14. Genetic variation and seed zones of douglas-fir in the Siskiyou National Forest. Forest Service research paper

    SciTech Connect

    Campbell, R.K.; Sugano, A.I.

    1993-07-01

    The provisional seed zones and breeding zones were developed for Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) in the Siskiyou National Forest in southwestern Oregon. Zones were based on maps of genetic variation patterns obtained by evaluating genotypes of trees from 260 locations in the region. Genotypes controlling growth vigor and growth rhythm were assessed in the common garden. Within the Forest, three breeding blocks were recommended, with different numbers of elevational bands in each block: from 0 to 610 meters, from 611 to 838 meters, and then a series of bands 152 meters wide at higher elevations.

  15. Multiday production of condensing organic aerosol mass in urban and forest outflow

    DOE PAGES

    Lee-Taylor, J.; Hodzic, A.; Madronich, S.; ...

    2014-07-03

    Secondary organic aerosol (SOA) production in air masses containing either anthropogenic or biogenic (terpene-dominated) emissions is investigated using the explicit gas-phase chemical mechanism generator GECKO-A. Simulations show several-fold increases in SOA mass continuing for several days in the urban outflow, even as the initial air parcel is diluted into the regional atmosphere. The SOA mass increase in the forest outflow is more modest (∼50%) and of shorter duration (1–2 days). The production in the urban outflow stems from continuing oxidation of gas-phase precursors which persist in equilibrium with the particle phase, and can be attributed to multigenerational reaction products ofmore » both aromatics and alkanes. In particular we find large contributions from substituted maleic anhydrides and multi-substituted peroxide-bicyclic alkenes. The results show that the predicted production is a robust feature of our model even under changing atmospheric conditions, and contradict the notion that SOA undergoes little mass production beyond a short initial formation period. The results imply that anthropogenic aerosol precursors could influence the chemical and radiative characteristics of the atmosphere over an extremely wide region, and that SOA measurements near precursor sources may routinely underestimate this influence.« less

  16. Multiday production of condensing organic aerosol mass in urban and forest outflow

    NASA Astrophysics Data System (ADS)

    Lee-Taylor, J.; Hodzic, A.; Madronich, S.; Aumont, B.; Camredon, M.; Valorso, R.

    2014-07-01

    Secondary organic aerosol (SOA) production in air masses containing either anthropogenic or biogenic (terpene-dominated) emissions is investigated using the explicit gas-phase chemical mechanism generator GECKO-A. Simulations show several-fold increases in SOA mass continuing for several days in the urban outflow, even as the initial air parcel is diluted into the regional atmosphere. The SOA mass increase in the forest outflow is more modest (∼50%) and of shorter duration (1-2 days). The production in the urban outflow stems from continuing oxidation of gas-phase precursors which persist in equilibrium with the particle phase, and can be attributed to multigenerational reaction products of both aromatics and alkanes. In particular we find large contributions from substituted maleic anhydrides and multi-substituted peroxide-bicyclic alkenes. The results show that the predicted production is a robust feature of our model even under changing atmospheric conditions, and contradict the notion that SOA undergoes little mass production beyond a short initial formation period. The results imply that anthropogenic aerosol precursors could influence the chemical and radiative characteristics of the atmosphere over an extremely wide region, and that SOA measurements near precursor sources may routinely underestimate this influence.

  17. Multiday production of condensing organic aerosol mass in urban and forest outflow

    NASA Astrophysics Data System (ADS)

    Lee-Taylor, J.; Hodzic, A.; Madronich, S.; Aumont, B.; Camredon, M.; Valorso, R.

    2015-01-01

    Secondary organic aerosol (SOA) production in air masses containing either anthropogenic or biogenic (terpene-dominated) emissions is investigated using the explicit gas-phase chemical mechanism generator GECKO-A. Simulations show several-fold increases in SOA mass continuing for multiple days in the urban outflow, even as the initial air parcel is diluted into the regional atmosphere. The SOA mass increase in the forest outflow is more modest (~50%) and of shorter duration (1-2 days). The multiday production in the urban outflow stems from continuing oxidation of gas-phase precursors which persist in equilibrium with the particle phase, and can be attributed to multigenerational reaction products of both aromatics and alkanes, especially those with relatively low carbon numbers (C4-15). In particular we find large contributions from substituted maleic anhydrides and multi-substituted peroxide-bicyclic alkenes. The results show that the predicted production is a robust feature of our model even under changing atmospheric conditions and different vapor pressure schemes, and contradict the notion that SOA undergoes little mass production beyond a short initial formation period. The results imply that anthropogenic aerosol precursors could influence the chemical and radiative characteristics of the atmosphere over an extremely wide region, and that SOA measurements near precursor sources may routinely underestimate this influence.

  18. Farmers' perception on the importance of variegated grasshopper (Zonocerus variegatus (L.)) in the agricultural production systems of the humid forest zone of Southern Cameroon

    PubMed Central

    Kekeunou, Sévilor; Weise, Stephan; Messi, Jean; Tamò, Manuel

    2006-01-01

    Background Zonocerus variegatus (Linnaeus, 1758) (Orthoptera: Pyrgomorphidae) is known as an agricultural pest in West and Central Africa. However, its importance in the agricultural production system in Cameroon has not been investigated. The study assesses farmers' perception on the importance of Z. variegatus in the agricultural production systems of the humid forest zone of Southern Cameroon. Methods Research was carried out in 5 villages of each of three Agro-Ecological, Cultural and Demographic Blocks (AECD-Blocks) of the Forest Margin Benchmark Area (FMBA). In each village, a semi-structured survey was used; male and female groups of farmers were interviewed separately. Results Z. variegatus is present throughout the humid forest zone of Southern Cameroon, where it is ranked as the third most economically important insect pest of agriculture. In the farmers' opinion, Z. variegatus is a polyphagous insect with little impact on young perennial crops. The length of the pre-farming fallow does not affect Z. variegatus pest pressure in the following crops. The increased impact of the grasshopper observed today in the fields, compared to what existed 10 years ago is as a result of deforestation and increase in surface of herbaceous fallow. The damage caused by Z. variegatus is higher in fields adjacent to C. odorata and herbaceous fallows than in those adjacent to forests and shrubby fallows. The fight against this grasshopper is often done through physical methods carried out by hand, for human consumption. The farmers highlight low usage of the chemical methods and a total absence of biological and ecological methods. Conclusion Farmers' perception have contributed to understanding the status of Z. variegatus in the humid forest zone of Southern Cameroon. The results are in general similar to those obtained in other countries. PMID:16573815

  19. Research Progress of Artificial Forest in the Remediation of Heavy Metal Contaminated Soils

    NASA Astrophysics Data System (ADS)

    Jiafang, MA; Guangtao, MENG; Liping, HE; Guixiang, LI

    2017-01-01

    (1) Remediation of soil contaminated by heavy metals has become a hot topic in the world, and phytoremediation technology is the most widely used. (2) In addition to traditional economic benefits, ecological benefits of artificial forest have been more and more important, which are very helpful to soil polluted with heavy metals in the environment. (3) The characteristics of heavy metal pollution of soil and plantations of repair mechanism have been reviewed, and the current mining areas, wetlands, urban plantations on heavy metal elements have enriched the research results. The purpose is to find a new path for governance of heavy metal soil pollution.

  20. Protected forests in Europe approaches-harmonising the definitions for international comparison and forest policy making.

    PubMed

    Parviainen, Jari; Frank, Georg

    2003-01-01

    Comparison of forest protection between regions in Europe is extremely difficult, because there is such wide variation of strategies, procedures and constraints; the way forests have been used historically and their present closeness to nature also varies, and furthermore so does the definition of what constitutes a forest. For the European Ministerial Conference on the Protection of Forests in Europe (MCPFE) in 2003, forest protection has been harmonised into three categories for the sake of comparison: protection to safeguard biodiversity, protection of landscape and specific natural features, and protective forest functions. There is no single, uniform and universal model and no internationally agreed target with respect to the percentage of forests which should be protected. What is more important than a fixed percentage level of forested area (e.g. 5 or 10%) is that the protection network should be biogeographically and ecologically representative and accordingly distributed on a regional basis. Long-term practical experience and research have proved that conservation of different species of organisms can be assured by appropriate silvicultural management of multifunctional production forests. Consequently, the focus of debate in Europe appears to shift more and more from total protection in segregated areas to 'precision protection' and to combining protection and timber production in the holistic, integrated concept of modern management of forest areas.Advances in regional ecological planning and the growing adoption of naturalistic forest management practices have slowed the decline of the biological diversity in the multifunctional production forests. However, this fact is not yet widely and sufficiently acknowledged and appreciated. There is consequently a political and scientific need for continued study of the effects of naturalistic silvicultural management on the biodiversity of forests. Information from such research is crucially needed before new

  1. Research Productivity of Sports Medicine Fellowship Faculty

    PubMed Central

    Cvetanovich, Gregory L.; Saltzman, Bryan M.; Chalmers, Peter N.; Frank, Rachel M.; Cole, Brian J.; Bach, Bernard R.

    2016-01-01

    Background: Research productivity is considered an important factor in academic advancement in sports medicine. No study to date has evaluated academic productivity and correlates of academic rank for sports medicine fellowship faculty. Purpose: To describe the academic productivity of American Orthopaedic Society for Sports Medicine (AOSSM) fellowship program faculty and to determine the association between academic productivity, fellowship characteristics, and academic rank. Study Design: Descriptive epidemiology study. Methods: Characteristics of orthopaedic sports medicine fellowship programs were obtained from the AOSSM and program websites. Metrics of academic productivity (Hirsch index [h index], I-10 index, publications, citations, and number of publications in several journals) were obtained from Scopus. Statistical analyses were conducted to determine whether academic productivity differs with fellowship attributes and academic rank. Results: A total of 90 AOSSM sports medicine fellowship programs with 610 associated faculty members were identified. Faculty were predominantly male (94%), at academic medical centers (74%), members of AOSSM (71%), and sports medicine–fellowship trained (84%). Faculty had a median of 18 (range, 0-684) publications overall, including a median of 3 (range, 0-161) publications since 2012. All measures of academic productivity were significantly higher among faculty employed at academic medical centers compared with those not employed at academic centers (P < .05 in all cases). On multivariate ordinal regression analysis, the best correlates of higher academic rank were higher cumulative h index (1.22; P < .001) and longer time in practice since fellowship (1.14; P < .001), which predicted 63.8% of the variance in academic rank. Fellowships with a larger number of fellows had more publications and citations per faculty member, higher faculty cumulative h index, and more publications in the American Journal of Sports Medicine

  2. Which mechanisms dominate the net effects of forest thinning on water yield and forest productivity in the semi-arid Santa Fe Municipal Watershed?

    NASA Astrophysics Data System (ADS)

    Dugger, A. L.; Tague, C.; Allen, C. D.; Ringler, T.

    2013-12-01

    It remains an open question whether, and under what conditions, forest thinning leads to water yield increases or decreases. Observations point in both directions, with clear examples of woody plant removal leading to increases, encroachment causing no change, and tree mortality resulting in both increases and decreases in downstream water yields. These seemingly conflicting results imply that different processes may dominate vegetation controls on catchment water yield, and that these dominant processes may vary with environment. While a framework has been proposed for hydrologic sensitivity to woody plant changes in grassland-woodland systems, these hypotheses have yet to be fully vetted in forested mountain catchments. To address this gap, we use a coupled ecologic-hydrologic modeling system (RHESSys) to examine different mechanisms through which thinning alters water partitioning: (1) increased (incoming) shortwave and decreased (canopy) longwave radiation, (2) decreased transpiration and increased surface evaporation, (3) decreased canopy and increased near-surface turbulent fluxes. Ultimately the net effect of forest thinning on water yield depends on the balance of these different mechanisms, and we seek to better understand how topographic, subsurface geophysical, and climatic conditions influence this balance. We focus on a semi-arid, forested, mountain watershed since these hydrologic systems are not only vital water supply sources for a large portion of the Southwest U.S., but also highly sensitive to changes in vegetation cover. We use an existing application of RHESSys in the Santa Fe (New Mexico) Municipal Watershed that has been validated against measurements of radiation, water, and carbon fluxes at nearby Ameriflux sites covering a range of conditions including undisturbed, thinned, and burned forest. We evaluate the effects of thinning on both downstream water yield and forest productivity across different site conditions (slope/aspect, soil water

  3. Increasing the biomass production of short rotation coppice forests. Progress report

    SciTech Connect

    Steinbeck, K.; Brown, C. L.

    1980-09-01

    The objective of the project is to increase biomass yields from coppice forests by admixing tree species (Alnus glutinosa, Robinia pseudoacacia and others) to plantations of Platanus occidentalis and Liquidambar styraciflua. Yield increases due to intensive cultivation, especially fertilization and irrigation, will be documented. A genetic improvement program of promising candidate species both through the identification of superior genotypes and mass cloning with tissue culture is also included. Three plantings have been established successfully to screen candidate species on various sites and to test the effects of weed control, fertilization and irrigation on short rotation forests. Two plantations in Georgia are in their 2nd and 3rd growing seasons while one in South Carolina is in its 1st growing season. A two acre plantation has been established to test development of geographic seed source material for sycamore. A nursery is in operation to develop seedling production methods for new species and to grow and maintain genetic material. Mass cloning of selected material by tissue culture techniques has produced material for testing in outplantings.

  4. The contribution of harvest residue to ecosystem carbon balance over the production cycle of managed forests

    NASA Astrophysics Data System (ADS)

    Noormets, A.; McNulty, S.; Domec, J.; Gavazzi, M. J.; Treasure, E.; Sun, G.; King, J. S.; Chen, J.

    2010-12-01

    It has been proposed that forests could be managed for carbon sequestration to mitigate the increase in atmospheric CO2. However, intensive management tends to deplete ecosystem resources (e.g. nutrients and soil organic matter) that make high productivity possible, thus potentially undermining the sustainability of such practices. In forest ecosystems, we have seen soil carbon loss exceed new litter inputs. While the cause of this loss is not clear, the increased frequency of disturbance associated with harvests and management practices likely contributes to the accelerated decomposition rates. Furthermore, the additional pulse of harvest residue of leaves, branches, roots, and coarse woody debris is likely to contribute to enhanced CO2 emissions. Here we evaluate the magnitude of emissions from post-harvest debris in relation to total ecosystem C budget in two loblolly pine plantations in SE-US, and compare our results to three other pine harvest chronosequences in North America. The initial magnitude of ecosystem respiration decreased and the duration of the source phase increased with latitude such that the integrated source phase emissions were proportional (130-140%) to the amount of CWD left at the site following the harvest. However, this relationship may vary by existing soil carbon and moisture availability. The results will be evaluated in the context of potential sources of uncertainty.

  5. Biological feedbacks dominate environmental sensitivity of net biomass production in temperate and boreal North American forests

    NASA Astrophysics Data System (ADS)

    Hember, R. A.; Kurz, W. A.; Coops, N.; Boisvenue, C.; Metsaranta, J. M.

    2012-12-01

    Considerable uncertainty remains in how environmental changes are impacting forest biomass dynamics. Here, we analyze a large sample of permanent sample plots and tree-ring chronologies from temperate and boreal forests across North America to empirically derive environmental sensitivity and constrain ecophysiological model simulations of biomass growth (G) and mortality (M). We argue that observed cross-site variation of G for common forest types reflects a combination of genetic differentiation and equilibrium sensitivity to environmental conditions. Growth of all tested tree species exhibited greater than expected exponential sensitivity to temperature and widely varying responses to water deficits. A high degree of persistence in temporal responses of G to environmental change, evident in both tree-ring chronologies and models, suggests that high estimates of equilibrium sensitivity derived from cross-site variation may be attributed to biological feedbacks (e.g., leaf area expansion) that delay and amplify environmental sensitivity above levels more often inferred from short-term transient variation. Long-term plots and tree-ring chronologies in western North America suggest that environmental changes contributed to significant enhancement of G over the 20th century. Increases in M above background levels were triggered by a critical level of modelled actual evapotranspiration (ETa). Leaf area expansion and consequent positive trends in transpiration were the primary factors causing stands to exceed critical levels of ETa. Positive dependence of M on transpiration led us to propose that hydraulic failure may be the primary mechanism causing drought-induced regular mortality and that recent trends may reflect a negative feedback response to 20th century growth enhancement that allowed biomass to build up to levels that were eventually unsustainable through the 1980's and 90's droughts. The effect of the mortality feedback on net biomass production (ΔB) is

  6. Unearthing Secrets of the Forest

    USGS Publications Warehouse

    Beldin, Sarah I.; Perakis, Steven S.

    2009-01-01

    Forests are a defining feature for large areas of the Pacific northwestern United States from northern California to Alaska. Coniferous temperate rainforests in the western Cascade and coastal mountain ranges are appreciated for their aesthetic value and abundant natural resources. Few people recognize the riches beneath the forest floor; yet, soil is a key ecosystem component that makes each type of forest unique. Soils harbor immense biological diversity and control the release of water and nutrients that support life above ground. Understanding how carbon and nutrients cycle in forests, known as forest biogeochemistry, is crucial for evaluating forest productivity, composition, diversity, and change. At the U.S. Geological Survey (USGS) Forest and Rangeland Ecosystem Science Center, research in the Terrestrial Ecosystems Laboratory focuses on nutrient cycling in five themes: climate change, nutrition and sustainability, fire effects, restoration, and forest-stream linkages. This research is essential to understand the entire forest ecosystem and to use the best science available to make informed policy and management decisions.

  7. Measuring Individual Research Productivity: A Review and Development of the Integrated Research Productivity Index

    ERIC Educational Resources Information Center

    Duffy, Ryan D.; Martin, Helena M.; Bryan, Nicole A.; Raque-Bogdan, Trisha L.

    2008-01-01

    The purpose of the present study was to investigate methods of measuring individual research productivity for counseling psychologists. Using the 60 members of the "Journal of Counseling Psychology" editorial board, the authors computed a comparison of 6 popular indices of productivity, revealing considerable levels of positive skewness,…

  8. Monitoring firefighter exposure to air toxins at prescribed burns of forest and range biomass. Forest Service research paper

    SciTech Connect

    Reinhardt, T.E.

    1991-10-01

    A variety of potent air toxins are in the smoke produced by burning forest and range biomass. Preliminary data on firefighter exposures to carbon monoxide and formaldehyde at four prescribed burns of Western United States natural fuels are presented. Formaldehyde may be correlated to carbon monoxide emissions. The firefighters' exposures to these compounds relative to workplace standards are discussed.

  9. Monitoring 2009 Forest Disturbance Across the Conterminous United States, Based on Near-Real Time and Historical MODIS 250 Meter NDVI Products

    NASA Technical Reports Server (NTRS)

    Spruce, J.; Hargrove, W. W.; Gasser, G.; Smoot, J. C.; Kuper, P.

    2009-01-01

    This case study shows the promise of computing current season forest disturbance detection products at regional to CONUS scales. Use of the eMODIS expedited product enabled a NRT CONUS forest disturbance detection product, a requirement for an eventual, operational forest threat EWS. The 2009 classification product from this study can be used to quantify the areal extent of forest disturbance across CONUS, although a quantitative accuracy assessment still needs to be completed. However, the results would not include disturbances that occurred after July 27, such as the Station Fire. While not shown here, the project also produced maximum NDVI products for the June 10-July 27 period of each year of the 2000-2009 time frame. These products could be applied to compute forest change products on an annual basis. GIS could then be used to assess disturbance persistence. Such follow-on work could lead to attribution of year in which a disturbance occurred. These products (e.g., Figures 6 and 7) may also be useful for assessing forest change associated with climate change, such as carbon losses from bark beetle-induced forest mortality in the Western United States. Other MODIS phenological products are being assessed for aiding forest monitoring needs of the EWS, including cumulative NDVI products (Figure 10).

  10. Socio-ecological costs of Amazon nut and timber production at community household forests in the Bolivian Amazon

    PubMed Central

    Mohren, Frits; Ascarrunz, Nataly; Dressler, Wolfram; Peña-Claros, Marielos

    2017-01-01

    The Bolivian Amazon holds a complex configuration of people and forested landscapes in which communities hold secure tenure rights over a rich ecosystem offering a range of livelihood income opportunities. A large share of this income is derived from Amazon nut (Bertholletia excelsa). Many communities also have long-standing experience with community timber management plans. However, livelihood needs and desires for better living conditions may continue to place these resources under considerable stress as income needs and opportunities intensify and diversify. We aim to identify the socioeconomic and biophysical factors determining the income from forests, husbandry, off-farm and two keystone forest products (i.e., Amazon nut and timber) in the Bolivian Amazon region. We used structural equation modelling tools to account for the complex inter-relationships between socioeconomic and biophysical factors in predicting each source of income. The potential exists to increase incomes from existing livelihood activities in ways that reduce dependency upon forest resources. For example, changes in off-farm income sources can act to increase or decrease forest incomes. Market accessibility, social, financial, and natural and physical assets determined the amount of income community households could derive from Amazon nut and timber. Factors related to community households’ local ecological knowledge, such as the number of non-timber forest products harvested and the number of management practices applied to enhance Amazon nut production, defined the amount of income these households could derive from Amazon nut and timber, respectively. The (inter) relationships found among socioeconomic and biophysical factors over income shed light on ways to improve forest-dependent livelihoods in the Bolivian Amazon. We believe that our analysis could be applicable to other contexts throughout the tropics as well. PMID:28235090

  11. Socio-ecological costs of Amazon nut and timber production at community household forests in the Bolivian Amazon.

    PubMed

    Soriano, Marlene; Mohren, Frits; Ascarrunz, Nataly; Dressler, Wolfram; Peña-Claros, Marielos

    2017-01-01

    The Bolivian Amazon holds a complex configuration of people and forested landscapes in which communities hold secure tenure rights over a rich ecosystem offering a range of livelihood income opportunities. A large share of this income is derived from Amazon nut (Bertholletia excelsa). Many communities also have long-standing experience with community timber management plans. However, livelihood needs and desires for better living conditions may continue to place these resources under considerable stress as income needs and opportunities intensify and diversify. We aim to identify the socioeconomic and biophysical factors determining the income from forests, husbandry, off-farm and two keystone forest products (i.e., Amazon nut and timber) in the Bolivian Amazon region. We used structural equation modelling tools to account for the complex inter-relationships between socioeconomic and biophysical factors in predicting each source of income. The potential exists to increase incomes from existing livelihood activities in ways that reduce dependency upon forest resources. For example, changes in off-farm income sources can act to increase or decrease forest incomes. Market accessibility, social, financial, and natural and physical assets determined the amount of income community households could derive from Amazon nut and timber. Factors related to community households' local ecological knowledge, such as the number of non-timber forest products harvested and the number of management practices applied to enhance Amazon nut production, defined the amount of income these households could derive from Amazon nut and timber, respectively. The (inter) relationships found among socioeconomic and biophysical factors over income shed light on ways to improve forest-dependent livelihoods in the Bolivian Amazon. We believe that our analysis could be applicable to other contexts throughout the tropics as well.

  12. Nutrient limitation on ecosystem productivity and processes of mature and old-growth subtropical forests in China.

    PubMed

    Hou, Enqing; Chen, Chengrong; McGroddy, Megan E; Wen, Dazhi

    2012-01-01

    Nitrogen (N) is considered the dominant limiting nutrient in temperate regions, while phosphorus (P) limitation frequently occurs in tropical regions, but in subtropical regions nutrient limitation is poorly understood. In this study, we investigated N and P contents and N:P ratios of foliage, forest floors, fine roots and mineral soils, and their relationships with community biomass, litterfall C, N and P productions, forest floor turnover rate, and microbial processes in eight mature and old-growth subtropical forests (stand age >80 yr) at Dinghushan Biosphere Reserve, China. Average N:P ratios (mass based) in foliage, litter (L) layer and mixture of fermentation and humus (F/H) layer, and fine roots were 28.3, 42.3, 32.0 and 32.7, respectively. These values are higher than the critical N:P ratios for P limitation proposed (16-20 for foliage, ca. 25 for forest floors). The markedly high N:P ratios were mainly attributed to the high N concentrations of these plant materials. Community biomass, litterfall C, N and P productions, forest floor turnover rate and microbial properties were more strongly related to measures of P than N and frequently negatively related to the N:P ratios, suggesting a significant role of P availability in determining ecosystem production and productivity and nutrient cycling at all the study sites except for one prescribed disturbed site where N availability may also be important. We propose that N enrichment is probably a significant driver of the potential P limitation in the study area. Low P parent material may also contribute to the potential P limitation. In general, our results provided strong evidence supporting a significant role for P availability, rather than N availability, in determining ecosystem primary productivity and ecosystem processes in subtropical forests of China.

  13. Nest box use and productivity of great crested flycatchers in prescribed-burned longleaf pine forests

    USGS Publications Warehouse

    White, D.H.; Seginak, J.T.

    2000-01-01

    Managing for the endangered Red-cockaded Woodpecker (Picoides borealis) on federal lands requires burning large tracts of mature pine forests every 3-5 yr. Many cavity trees that serve as potential nest sites for primary and secondary hole-nesting birds are destroyed by fire. We assessed the efficacy of a nest box program for the Great Crested Flycatcher (Myiarchus crinitus) at Carolina Sandhills National Wildlife Refuge, an area intensively managed for Red-cockaded Woodpeckers. During 1996-1998, we installed and monitored 330 (30 in each of 11 sites) nest boxes in mature (>60 yr) longleaf pine (Pinus palustris) tracts that were burned either in April-June (warm season) or December-March (cool season). Prescribed-burned sites were nearly devoid of snags; we estimated only 0.8/ ha in cool-season burns and 1.7/ha in warm-season burns. Great Crested Flycatchers built nests in 20% of the boxes available to them. Clutch sizes were larger in warm-season burns than in cool-season burns, but fledging success (fledglings/nest hatching -1 egg) was lower. Twenty-two of 59 Great Crested Flycatcher nests were depredated and the proportions in each burn class were similar. We recommend the installation of nest boxes for Great Crested Flycatchers in prescribed-burned pine forests, but additional research is needed in these habitats on nest depredation rates and causes.

  14. Spatial Patterns between Regolith Thickness and Forest Productivity in the Southern Sierra CZO

    NASA Astrophysics Data System (ADS)

    Ferrell, R. M.; Ferrell, D. F.; Hartsough, P. C.; O'Geen, T. T.

    2015-12-01

    Soil in conjunction with underlying weathered bedrock make up what is referred to as regolith, which can be thought of as the substrate that actively contributes water and nutrients to above ground biomass. As a result, regolith thickness is an important regulating factor of forest health and drought tolerance in the Sierra Nevada. Our project examined the relationships between landscape position, regolith thickness, and tree productivity within a sub watershed of the Southern Sierra Critical Zone Observatory. We hypothesized that tree productivity will increase with increasing regolith thickness. Data was collected in the summer of 2015 at sixty-five sites within a 522-ha watershed averaging 1180m in elevation with a MAP of 80cm and a MAT of 11C. Sites were randomly selected from a grid and then stratified in the field to capture representative samples from different landscape positions. Regolith was sampled using a hand auger with attachable extensions. At each site we augered to hard bedrock or a maximum depth of 7.56 m, which ever was shallower. Biomass measurements were made for all conifer species (DBH>20cm) within a 10m radius of the primary auger hole. Tree age was measured from a representative tree for all species in the plots. Preliminary findings suggest that there is a weak correlation between landscape position/slope and regolith thickness, likely due to differences in lithology. It also appears that terrain shape can result in conflicting outcomes: 1. It can focus water to promote physical and chemical weathering and thick regolith; or, 2. water focusing can result in landscape scouring, removing soil and weathered bedrock to create shallow regolith. Productivity appears to be a function of regolith thickness, effective precipitation and landscape position. Water collecting areas in the lower watershed are shallow to bedrock, but typically receive high amounts of effective precipitation resulting in greater tree productivity. Moreover, thick regolith

  15. Multiday production of condensing organic aerosol mass in urban and forest outflow

    DOE PAGES

    Lee-Taylor, J.; Hodzic, A.; Madronich, S.; ...

    2015-01-16

    Secondary organic aerosol (SOA) production in air masses containing either anthropogenic or biogenic (terpene-dominated) emissions is investigated using the explicit gas-phase chemical mechanism generator GECKO-A. Simulations show several-fold increases in SOA mass continuing for multiple days in the urban outflow, even as the initial air parcel is diluted into the regional atmosphere. The SOA mass increase in the forest outflow is more modest (~50%) and of shorter duration (1–2 days). The multiday production in the urban outflow stems from continuing oxidation of gas-phase precursors which persist in equilibrium with the particle phase, and can be attributed to multigenerational reaction productsmore » of both aromatics and alkanes, especially those with relatively low carbon numbers (C4–15). In particular we find large contributions from substituted maleic anhydrides and multi-substituted peroxide-bicyclic alkenes. The results show that the predicted production is a robust feature of our model even under changing atmospheric conditions and different vapor pressure schemes, and contradict the notion that SOA undergoes little mass production beyond a short initial formation period. The results imply that anthropogenic aerosol precursors could influence the chemical and radiative characteristics of the atmosphere over an extremely wide region, and that SOA measurements near precursor sources may routinely underestimate this influence.« less

  16. Tree Size Inequality Reduces Forest Productivity: An Analysis Combining Inventory Data for Ten European Species and a Light Competition Model.

    PubMed

    Bourdier, Thomas; Cordonnier, Thomas; Kunstler, Georges; Piedallu, Christian; Lagarrigues, Guillaume; Courbaud, Benoit

    2016-01-01

    Plant structural diversity is usually considered as beneficial for ecosystem functioning. For instance, numerous studies have reported positive species diversity-productivity relationships in plant communities. However, other aspects of structural diversity such as individual size inequality have been far less investigated. In forests, tree size inequality impacts directly tree growth and asymmetric competition, but consequences on forest productivity are still indeterminate. In addition, the effect of tree size inequality on productivity is likely to vary with species shade-tolerance, a key ecological characteristic controlling asymmetric competition and light resource acquisition. Using plot data from the French National Geographic Agency, we studied the response of stand productivity to size inequality for ten forest species differing in shade tolerance. We fitted a basal area stand production model that included abiotic factors, stand density, stand development stage and a tree size inequality index. Then, using a forest dynamics model we explored whether mechanisms of light interception and light use efficiency could explain the tree size inequality effect observed for three of the ten species studied. Size inequality negatively affected basal area increment for seven out of the ten species investigated. However, this effect was not related to the shade tolerance of these species. According to the model simulations, the negative tree size inequality effect could result both from reduced total stand light interception and reduced light use efficiency. Our results demonstrate that negative relationships between size inequality and productivity may be the rule in tree populations. The lack of effect of shade tolerance indicates compensatory mechanisms between effect on light availability and response to light availability. Such a pattern deserves further investigations for mixed forests where complementarity effects between species are involved. When studying the

  17. Tree Size Inequality Reduces Forest Productivity: An Analysis Combining Inventory Data for Ten European Species and a Light Competition Model

    PubMed Central

    Bourdier, Thomas; Cordonnier, Thomas; Kunstler, Georges; Piedallu, Christian; Lagarrigues, Guillaume; Courbaud, Benoit

    2016-01-01

    Plant structural diversity is usually considered as beneficial for ecosystem functioning. For instance, numerous studies have reported positive species diversity-productivity relationships in plant communities. However, other aspects of structural diversity such as individual size inequality have been far less investigated. In forests, tree size inequality impacts directly tree growth and asymmetric competition, but consequences on forest productivity are still indeterminate. In addition, the effect of tree size inequality on productivity is likely to vary with species shade-tolerance, a key ecological characteristic controlling asymmetric competition and light resource acquisition. Using plot data from the French National Geographic Agency, we studied the response of stand productivity to size inequality for ten forest species differing in shade tolerance. We fitted a basal area stand production model that included abiotic factors, stand density, stand development stage and a tree size inequality index. Then, using a forest dynamics model we explored whether mechanisms of light interception and light use efficiency could explain the tree size inequality effect observed for three of the ten species studied. Size inequality negatively affected basal area increment for seven out of the ten species investigated. However, this effect was not related to the shade tolerance of these species. According to the model simulations, the negative tree size inequality effect could result both from reduced total stand light interception and reduced light use efficiency. Our results demonstrate that negative relationships between size inequality and productivity may be the rule in tree populations. The lack of effect of shade tolerance indicates compensatory mechanisms between effect on light availability and response to light availability. Such a pattern deserves further investigations for mixed forests where complementarity effects between species are involved. When studying the

  18. Soil fluxes of carbon dioxide, nitrous oxide, and methane at a productive temperate deciduous forest

    SciTech Connect

    Bowden, R.D.; Rullo, G.; Stevens, G.R.; Steudler, P.A.

    2000-02-01

    The authors measured CO{sub 2}, N{sub 2}O, and CH{sub 4} fluxes between soils and the atmosphere in ambient and N-addition plots at a productive black cherry-sugar maple forest in northwest Pennsylvania to examine the link between N-cycling and trace gas fluxes. Fluxes were estimated using in-situ chambers. Net annual N mineralization was 121.0 kg N ha{sup {minus}1}yr{sup {minus}1}, and net nitrification was 85.8 kg N ha{sup {minus}1}yr{sup {minus}1}, or 71% of net mineralization. Carbon dioxide efflux and CH{sub 4} uptake were among the highest rates reported for temperate deciduous forests. Emissions of N{sub 2}O were within the range of rates reported elsewhere, including locations with lower rates of N-cycling. A short-term study (May-Oct.) showed that N fertilization reduced both CO{sub 2} emissions and CH{sub 4} uptake. N{sub 2}O effluxes in fertilized plots were not different from control plots. The relatively high rate of soil respiration corresponded to a high rate of N-cycling; however, N{sub 2}O emissions were not necessarily result in large emissions of N{sub 2}O. Concurrent rapid rates of N-cycling and high rates of CH{sub 4} uptake did not support the hypothesis that N-cycling rates directly control CH{sub 4} uptake. Links between N-cycling and CH{sub 4} oxidation are complex; the influence of N-cycling on flux rates must consider not only the rate of cycling, but also the disposition of N-cycling products, and the factors that influence rates of N dynamics.

  19. Salmonberry and salal annual aerial stem production: The maintenance of shrub cover in forest stands

    USGS Publications Warehouse

    Tappeiner, J. C.; Zasada, J.; Huffman, D.; Ganio, L.

    2001-01-01

    Annual sprouting of aerial stems and ramets enables populations of salmonberry (Rubus spectabilis Pursh), salal (Gaultheria shallon Pursh), and probably other forest shrubs to maintain dense covers (>20 000 stems/ha). We studied annual stem production of salmonberry on cut (all stems cut within 15 cm of the ground) and uncut (stems were not treated) plots for 8 years and salal for 5 years in the understories of Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco), alder, and riparian stands, as well as clearcuts, which are all common stand types in western Oregon. Mean salmonberry stem production on uncut plots ranged from 4.7 stemsA?ma??2A?yeara??1 (95% CI 2.9a??7.4) in alder stands and clearcuts to 1.6 stemsA?ma??2A?yeara??1 (95% CI 1.0a??2.6) in conifer stands. Mean salal production was greater, ranging from 58 stemsA?ma??2A?yeara??1 (95% CI 25a??135) to 8.6 stemsA?ma??2A?yeara??1 (95% CI 3.7a??20.1) on uncut plots in clearcuts and unthinned Douglas-fir stands, respectively. Annual production of both species was somewhat greater on cut plots. Most stems produced in early spring die by December, but enough are recruited to replace mortality of older stems. Stem density was maintained for 8 years for salmonberry and 5 years for salal on both cut and uncut plots. Based on length of rhizomes and bud density we estimate that only 1a??5% of the buds in the rhizomes are needed to support this annual stem production. Although these species sprout vigorously after their aerial stems are killed, disturbance is not necessary for maintaining a dense cover. It appears that, once established, salal, salmonberry, and probably other clonal forest shrubs can maintain a dense cover that can interfere with establishment of trees and other shrubs in canopy gaps or other openings.

  20. Oxygen effects on methane production and oxidation in humidtropical forest soils

    SciTech Connect

    Teh, Yit Arn; Silver, Whendee L.; Conrad, Mark E.

    2004-12-15

    We investigated the effects of oxygen (O2) concentration onmethane (CH4) production and oxidation in two humid tropical forests thatdiffer in long-term, time-averaged soil O2 concentrations. We identifiedsources and sinks of CH4 through the analysis of soil gas concentrations,surface emissions, and carbon isotope measurements. Isotope mass balancemodels were used to calculate the fraction of CH4 oxidized in situ.Complementary laboratory experiments were conducted to determine theeffects of O2 concentration on gross and net rates of methanogenesis.Field and laboratory experiments indicated that high levels of CH4production occurred in soils that contained between 9+-1.1 percent and19+-0.2 percent O2. For example, we observed CH4 concentrations in excessof 3 percent in soils with 9+-1.1 percent O2. CH4 emissions from thelower O2 sites were high (22-101 nmol CH4m2s1), and were equal inmagnitude to CH4 emissions from natural wetlands. During peak periods ofCH4 efflux, carbon dioxide (CO2) emissions became enriched in 13C becauseof high methanogenic activity. Gross CH4 production was probably greaterthan flux measurements indicated, as isotope mass balance calculationssuggested that 48-78 percent of the CH4 produced was oxidized prior toatmospheric egress. O2 availability influenced CH4 oxidation morestrongly than methanogenesis. Gross CH4 production was relativelyinsensitive to O2 concentrations in laboratory experiments. In contrast,methanotrophic bacteria oxidized a greater fraction of total CH4production with increasing O2 concentration, shifting the delta13Ccomposition of CH4 to values that were more positive. Isotopicmeasurements suggested that CO2 was an important source of carbon formethanogenesis in humid forests. The delta13C value of methanogenesis wasbetween -84 percent and -98 percent, which is well within the range ofCH4 produced from CO2 reduction, and considerably more depleted in 13Cthan CH4 formed from acetate.