78 research outputs found

    A Spatial Model of Long-Term Forest Fire Dynamics and Its Application to Forests in Western Siberia

    Get PDF
    This paper is devoted to developing a spatial model of wildfires in forests. Wildfires are a dominant factor in controlling the structure and life of boreal forest communities. The main parameters controlling the simulation of fire dynamics are: probability of occurrence of fire source during one year per square unit, probability of fire maturity of cell in k-th state of n-th successional line during one year, and fire spread probability for cell in a stage of some successional line during one year per square unit. The dependence of forest fire dynamics on climatic conditions is reflected in such general climatic parameters as mean seasonal air temperature, seasonal sum of precipitations, and maximum period between two successive rains during one season. Testing of the model is based upon data on long-term forest fire dynamics in North America and western Siberia

    The role of historical fire disturbance in the carbon dynamics of the pan-boreal region : a process-based analysis

    Get PDF
    Author Posting. © American Geophysical Union, 2007. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research 112 (2007): G02029, doi:10.1029/2006JG000380.Wildfire is a common occurrence in ecosystems of northern high latitudes, and changes in the fire regime of this region have consequences for carbon feedbacks to the climate system. To improve our understanding of how wildfire influences carbon dynamics of this region, we used the process-based Terrestrial Ecosystem Model to simulate fire emissions and changes in carbon storage north of 45°N from the start of spatially explicit historically recorded fire records in the twentieth century through 2002, and evaluated the role of fire in the carbon dynamics of the region within the context of ecosystem responses to changes in atmospheric CO2 concentration and climate. Our analysis indicates that fire plays an important role in interannual and decadal scale variation of source/sink relationships of northern terrestrial ecosystems and also suggests that atmospheric CO2 may be important to consider in addition to changes in climate and fire disturbance. There are substantial uncertainties in the effects of fire on carbon storage in our simulations. These uncertainties are associated with sparse fire data for northern Eurasia, uncertainty in estimating carbon consumption, and difficulty in verifying assumptions about the representation of fires that occurred prior to the start of the historical fire record. To improve the ability to better predict how fire will influence carbon storage of this region in the future, new analyses of the retrospective role of fire in the carbon dynamics of northern high latitudes should address these uncertainties.Funding for this study was provided by grants from the National Science Foundation Biocomplexity Program (ATM-0120468) and Office of Polar Programs (OPP-0531047 and OPP- 0327664); the National Aeronautics and Space Administration Land Cover Land Use Change Program (NAF-11142) and North America Carbon Program (NNG05GD25G); the Bonanza Creek LTER (Long-Term Ecological Research) Program (funded jointly by NSF grant DEB-0423442 and USDA Forest Service, Pacific Northwest Research Station grant PNW01- JV11261952-231); and the U.S. Geological Survey

    Fire Influences in Abies-Dominated Forests

    Get PDF
    Abies-dominated forests have a relatively low fire hazard when compared with vegetation types dominated by Pinus or Picea species. Although large quantities of fuel are present, the humid climate of Abies-dominated areas reduces the probability of fire. When fires occur after prolonged drought periods, fir can be essentially eliminated from an area because it is not resistant to fire. Abies spp. tend to be shade-tolerant, late successional species and only in the absence of fire do they compete successfully with species established early in the post-fire pattern. Abies-dominated forests are more susceptible to fire following disturbance which damages or removes tree crowns, and in turn permits solar energy to reduce the moisture content of forest floor fuels. Forest harvesting is one of the recent disturbances, but it is thought that defoliation and tree mortality caused by insects also increases fire hazard. This insect-wildfire hypothesis has been raised in a number of Abies-dominated areas around the world and seems intuitively plausible; yet there is little field evidence and very little experimental evidence to support they hypothesis

    Forest fire occurrence and silvicultural-economic prerequisites for protection improvement in forest regions of Krasnoyarsk Krai

    No full text
    The territory of the Krasnoyarsk Krai is substantially diverse in terms of climatic, silvicultural and economic conditions owing to its sufficient spread from the North to the South. These differences were to some extent taken into account when the forest fund of the Krasnoyarsk Krai was divided into seven forest regions: forest tundra of Central Siberia, highland taiga of Central Siberia, plain taiga of West Siberia, Angara region, subtaiga forest steppe of Central Siberia, Altai-Sayanskiy highland, Altai-Sayanskiy highland forest steppe. The regions show different levels of fire occurrence and different fire effects that require different levels of protection from forest fires. Optimization of the protection is based on activities that combine prevention and timely detection of fires depending on development of forest regions and intensity of forest management. The main focus of the paper is on possibility or inadvisability of prescribed fires, fire-use fires (fires that started naturally but were then managed for their beneficial effects) and the system of activities increasing fire resistance of the most valuable forests. It is justified that taking into account the effects of forest fires, selective protection of forests is expedient in forest-tundra Middle Siberia and highland taiga of Middle Siberia regions. The whole area of plain taiga of West Siberia region should be subject to protection but with various levels of intensity in different parts of it. The forest fund of Angara, subtaiga forest steppe of Middle Siberia, Altai-Sayanskiy highland, Altai-Sayanskiy highland forest steppe regions should be protected on the whole area. Application of prescribed fires is relevant in the subzone of South taiga, in the forest steppe zone as well as in the submontane and lowland taiga belts. Fire-use fires are admissible on limited areas in the subzones of Middle and North taiga

    Supported accommodation of young people with psychophysical disorders as a condition for social and pedagogical inclusion

    No full text
    The relevance of the study is due to the need to overcome social exclusion of adolescents and young people caused by their health condition and restrictions on life in the context of inclusion trends in the worldwide social policy and practice. In this connection, the article aims to justify and search for hospital-substitute format of social and pedagogical support for young people with psychophysical behavior disorders of an autism spectrum disorder (ASD) type. The leading approach in the research of this issue is an integrative activity-based approach that allows comprehensive consideration of socio-political, organizational-pedagogical and technological opportunities for active inclusion of families with children and adolescents with ASD into joint activities in a social settlement. In the article, results of sociological, and psychological-pedagogical studies of the issue of social inclusion of individuals at risks of their exclusion from society are presented; various types of social integration practices are typologically disclosed; the author’s structural-functional model of a supported living arrangement is substantiated; conditions and possibilities for its implementation by a public organization of parents having children with autism in the regional context as exemplified by a rural settlement are identified and shown. The information presented in the article is of practical value for specialists in social pedagogy and work, as well as for those who are trained for concrete competences of social support of families having children with disabilities. The results of the given socio-pedagogical project may be useful for the development of the social movement of parents
    corecore