Download or read book Response of Seedlings and Saplings to Canopy Gaps in Coastal Old Growth Forests written by Jennifer A. Passmore and published by . This book was released on 2007 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fine-scale disturbances involving the death of one to a few trees create gaps in the forest canopy and, where large-scale disturbances are rare, exert a dominant influence on community and population dynamics. I examine the natural regeneration and recruitment of seedlings and saplings following fine-scale, gap forming disturbances in old-growth stands within the Capilano, Seymour and Coquitlam River watersheds. I compared the abundance of western redcedar, western hemlock, and Pacific silver fir seedlings and saplings between plots located within and adjacent-to 20 gaps of known date of origin. I also destructively sampled seedlings and saplings of each species and applied dendroecological methods to determine the age of each sample, and to elucidate patterns of suppression and release in radial growth. My results support the paradigm of gap-scale canopy replacement. Seedlings and saplings were more abundant in gap versus forest environments, and exhibited increased rates of establishment and radial growth.
Download or read book Seedling Regeneration in Relation to Gap and Canopy Environments in Coastal Mixed Forest of California written by Terrel Brand and published by . This book was released on 2002 with total page 232 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Canopy Recruitment in Shade Tolerant Trees written by Charles Draper William Canham and published by . This book was released on 1984 with total page 388 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Eastern Forest Insects written by Whiteford Lee Baker and published by . This book was released on 1972 with total page 658 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Growth and Physiological Responses of Canopy Tree Species to Selection Harvests in a Northern Hardwood Forest written by Trevor A. Jones and published by . This book was released on 2006 with total page 298 pages. Available in PDF, EPUB and Kindle. Book excerpt: The basal area increment (BAI) response of trees to gap creation was generally positive; however, there was a lag in BAI response which typically lasted between one and three years. Tree size was the best predictor of both pre-harvest BAI and BAI response to gap creation. Large trees had the greatest BAI but did not respond as positively to gap creation as smaller trees. Unexpectedly, it was observed that the BAI response of the more shade tolerant species was more positive than the less tolerant species. This may be related to species differences in canopy structure, with the deep crowns of shade tolerant species providing increased light interception following gap creation. The management of tolerant hardwood forests in central Ontario is typically done using the selection harvest system where no more than one third of the stand basal area is removed in each harvest while a balanced distribution of tree sizes and species is maintained to ensure continual stand development. Because regeneration is achieved through the manipulation of the understory light environment, the response of tree seedlings and saplings to changing light availability has been well studied. However, little is known about either the physiological acclimation processes or the growth responses of canopy trees to gap creation. This thesis examines the physiological acclimation and growth responses of large trees to selection management and addresses the factors that determine the temporal pattern and magnitude of the growth response. In order to better understand growth responses of large trees to gap creation an experiment examining canopy physiological and morphological acclimation to gap creation was conducted. Leaves within the lower portions of the canopy experienced gradual increases in area-based maximum photosynthetic rates, stomatal conductance, and leaf nitrogen. No change in these variables was observed that could not be accounted for by changes in leaf mass per unit area. Both the growth and physiological studies point to the importance of increases in incident light in the lower portions of the canopy, in conjunction with slow acclimation responses, as drivers of whole tree carbon gain and growth following selection harvests.
Download or read book Proceedings of the Second Glacier Bay Science Symposium written by Alexander M. Milner and published by . This book was released on 1990 with total page 186 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Growth Release of Trees Following Fine scale Canopy Disturbances in Old growth Forests of Coastal British Columbia Canada written by and published by . This book was released on 2008 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Growth release of trees following canopy disturbances is of interest to ecological scientists and forest managers. Using dendroecological techniques, I examined growth release of canopy and subcanopy trees following the formation of natural, fine-scale canopy gaps in old-growth, western red cedar-western hemlock forests of coastal British Columbia. I aimed to quantify detailed information on release of the three shade-tolerant tree species that constitute these stands: western red cedar (Thuja plicata), western hemlock (Tsuga heterophylla), and Pacific silver fir (Abies amabilis). As a first step, I calibrated the radial-growth averaging method to account for regional-scale variability and capture a more complete range of growth releases that may occur following the formation of fine-scale gaps in the study stands. A 25% threshold, 5-year moving average, and 10-year window emerged as appropriate parameters for detecting releases using radial-growth averaging. Basal area increment was also the most appropriate growth index for detecting releases. Establishing these empirically-based criteria was important for quantifying the magnitude and duration of releases. Tree diameter and growth rate prior to release were the most important predictors of the magnitude and duration of releases, but identity of the tree species and distance from the gap center were also important predictors. Western hemlock and Pacific silver fir were often growing slowly both in the canopy and subcanopy, giving them tremendous potential to release. For these species, releases were generally intensive and persistent. In contrast, western red cedar were often growing quickly both in the canopy and subcanopy, giving them less potential to release. Compared to western hemlock and Pacific silver fir, western red cedar releases were less intensive and persistent. Patterns related to distance from the gap center emerged for trees growing along the north-south axis of gaps. Regardless of species, increa.
Download or read book Seedling Growth and Survivorship of Native Tree Species in Response to Light Heterogeneity in Wet Second growth Forests of Northeastern Costa Rica written by Silvia Iriarte and published by . This book was released on 2001 with total page 488 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Old Growth Forests written by Christian Wirth and published by Springer Science & Business Media. This book was released on 2009-07-07 with total page 518 pages. Available in PDF, EPUB and Kindle. Book excerpt: Many terms often used to describe old-growth forests imply that these forests are less vigorous, less productive and less stable than younger forests. But research in the last two decades has yielded results that challenge the view of old-growth forests being in decline. Given the importance of forests in battling climate change and the fact that old-growth forests are shrinking at a rate of 0.5% per year, these new results have come not a moment too soon. This book is the first ever to focus on the ecosystem functioning of old-growth forests. It is an exhaustive compendium of information that contains original work conducted by the authors. In addition, it is truly global in scope as it studies boreal forests in Canada, temperate old-growth forests in Europe and the Americas, and global tropical forests. Written in part to affect future policy, this eminently readable book is as useful for the scientist and student as it is for the politician and politically-interested layman.
Download or read book Current Abstracts written by and published by . This book was released on 1996-03 with total page 118 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Tropical Trees as Living Systems written by P. B. Tomlinson and published by Cambridge University Press. This book was released on 2010-06-10 with total page 700 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book assesses the scientific knowledge of tropical tree biology set against a background of community ecology and forest structure.
Download or read book Ecosystems of Disturbed Ground written by L.R. Walker and published by Elsevier. This book was released on 1999-12-17 with total page 881 pages. Available in PDF, EPUB and Kindle. Book excerpt: As the human population inexorably grows, its cumulative impact on the Earth's resources is hard to ignore. The ability of the Earth to support more humans is dependent on the ability of humans to manage natural resources wisely. Because disturbance alters resource levels, effective management requires understanding of the ecology of disturbance. This book is the first to take a global approach to the description of both natural and anthropogenic disturbance regimes that physically impact the ground. Natural disturbances such as erosion, volcanoes, wind, herbivory, flooding and drought plus anthropogenic disturbances such as foresty, grazing, mining, urbanization and military actions are considered. Both disturbance impacts and the biotic recovery are addressed as well as the interactions of different types of disturbance. Other chapters cover processes that are important to the understanding of disturbance of all types including soil processes, nutrient cycles, primary productivity, succession, animal behaviour and competition. Humans react to disturbances by avoiding, exacerbating, or restoring them or by passing environmental legislation. All of these issues are covered in this book. Managers need better predictive models and robust data-collections that help determine both site-specfic and generalized responses to disturbance. Multiple disturbances have a complex effect on both physical and biotic processes as they interact. This book provides a wealth of detail about the process of disturbance and recovery as well as a synthesis of the current state of knowledge about disturbance theory, with extensive documentation.
Download or read book Tree Rings Environment and Humanity written by Jeffrey S. Dean and published by Radiocarbon Department of Geosciences University of Arizona. This book was released on 1996 with total page 916 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Effects of Opening Size and Competition Levels on the Growth and Canopy Recruitment of Saplings in Northern Hardwood Forests written by John M. Goodburn and published by . This book was released on 2004 with total page 116 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Canadian Journal of Forest Research written by and published by . This book was released on 2003 with total page 816 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Effect of Disturbance on Natural Forest Regeneration in a Changing Tropical Environment written by Donald Mlambo and published by Frontiers Media SA. This book was released on 2023-11-22 with total page 105 pages. Available in PDF, EPUB and Kindle. Book excerpt: Recent research shows that tropical forests are experiencing changes driven by many factors including deforestation and fragmentation, over-exploitation, invasive species, wildfires, insect and pathogen outbreaks, drought, windstorms and other climatically-enhanced events. Due to climate change, these disturbance events are becoming unprecedented in their frequency, extent and intensity. There is increasing concern that they may impact natural forest regeneration processes and drive rare and sensitive tropical woody plant species along an extinction trajectory. Although natural regeneration has potential to enhance ecological resilience, support local biodiversity, and provide ecosystem goods and services, it is often overlooked as an approach that can be aligned with biodiversity conservation goals, ecological restoration and climate change mitigation targets. Promoting natural forest regeneration may actually be less costly and more effective for restoring ecosystem functions.
Download or read book General Technical Report PNW written by and published by . This book was released on 1991 with total page 564 pages. Available in PDF, EPUB and Kindle. Book excerpt:
