Download or read book Geographical Variation in Sitka Spruce Productivity and Its Dependence on Environmental Factors written by Richard V. Worrell and published by . This book was released on 1987 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Geographical Variation in Sitka Spruce Productivity and Its Dependence on Environmental Factors written by Richard V. Worrell and published by . This book was released on 1987 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The objective of this study was to investigate altitudinal and geographical variation in the productivity of Sitka spruce in upland Scotland, to relate this to environmental variables and to use the information to develop a basis for predicting Sitka spruce yield form site factors. A total of 188 0.04 ha temporary sample plots were established in 15 to 50 year old Sitka spruce stands at 37 sites in Scotland and northern England, mostly spanning the upper 200m elevation range of plantations. At each plot estimates of General Yield Class (GYC) were made and the following site factors were assessed; elevation, geomorphic shelter (topex), aspect, slope, soil type and rooting depth. In addition, estimates of wind-climate, mean summer temperature (June-September), mean annual accumulated temperature > 5.6°C and annual rainfall were made by extrapolation of forestry Commission "tatter flag" records and Meteorological Office data. GYC declined by about 3.2 - 4.0 m3 ha -1 yr -1 per 100 m increase in elevation due to the effects of increasingly adverse climatic and edaphic conditions, GYC was fairly closely correlated with elevation at the individual sites, but there was considerable site to site variation. GYC values at specific elevations were higher in inland and southern areas than in coastal and northern ones. The geographical pattern of the relationship between GYC and elevation was strikingly similar to the distributions of growing season temperatures and wind-climate. Correlation and multiple regression analysis demonstrated that GYC was well correlated with extrapolated values of accumulated temperature and tatter rate, these two variables accounting for up to 78 per cent of the variation in GYC in the best multiple regression models. GYC also proved to be correlated with aspect, topex, soil type and crop age. Productivity was highest on north and east-facing aspects and increased with greater levels of geomorphic shelter. Differences in soil type only accounted for a small amount of variation in GYC (2-3 per cent). GYC was significantly negatively correlated with crop age, probably as a result of improved standards of silvicultural treatment. The best multiple regression models accounted for 78-86 per cent of the variation in GYC and were associated with confidence limits of ±2.2 - 2.6 m3 ha -1 yr -1. The mean figure for predicting GYC for a single site (acquisition) was calculated to be ± m3 ha -1 yr -1, and this figure was confirmed by results of a validation survey. The information presented could easily be adapted for predicting productivity and assessing suitable upper planting limits in practical forestry.

Download or read book Forest Development in Cold Climates written by John Alden and published by Springer Science & Business Media. This book was released on 2013-06-29 with total page 565 pages. Available in PDF, EPUB and Kindle. Book excerpt: As forests decline in temperate and tropical climates, highly-developed countries and those striving for greater economic and social benefits are beginning to utilize marginal forests of high-latitude and mountainous regions for resources to satisfy human needs. The benefits of marginal forests range from purely aesthetic to providing resources for producing many goods and services demanded by a growing world population. Increased demands for forest resources and amenities and recent warming of high latitude climates have generated interest in reforestation and afforestation of marginal habitats in cold regions. Afforestation of treeless landscapes improves the environment for human habitation and provides for land use and economic prosperity. Trees are frequently planted in cold climates to rehabilitate denuded sites, for the amenity of homes and villages, and for wind shelter, recreation, agroforestry, and industrial uses. In addition, forests in cold climates reduce the albedo of the earth's surface in winter, and in summer they are small but significant long-lived sinks for atmospheric carbon dioxide. Finally, growth and reproductive success of forests at their geographic limits are sensitive indices of climatic change. As efforts to adapt forests to cold climates increase, however, new afforestation problems arise and old ones intensify. Austral, northern, and altitudinal tree limits are determined by many different factors. Current hypotheses for high-latitude tree limits are based on low growing-season temperatures that inhibit plant development and reproduction.

Download or read book Predicting the Productivity of Sitka Spruce on Upland Sites in Northern Britain written by R. Worrell and published by Bernan Press(PA). This book was released on 1987 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Proceedings written by and published by . This book was released on 1987 with total page 608 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Forestry Commission Bulletin written by and published by . This book was released on 1969 with total page 670 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Environmental Factors and the Growth of Sitka Spruce written by Douglas C. Malcolm and published by . This book was released on 1969 with total page 157 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Scottish Forestry written by and published by . This book was released on 2003 with total page 500 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Index to Theses with Abstracts Accepted for Higher Degrees by the Universities of Great Britain and Ireland and the Council for National Academic Awards written by and published by . This book was released on 2007 with total page 326 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book British Reports Translations and Theses written by British Library. Document Supply Centre and published by . This book was released on 1988 with total page 490 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Parent Tree Variation in Sitka Spruce Provenances written by E. R. Falkenhagen and published by . This book was released on 1978 with total page 10 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Woody Plant Seed Manual written by United States. Forest Service and published by Forest Service. This book was released on 2008 with total page 1240 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Woody Plant Seed Manual Agriculture Handbook 727 July 2008 written by and published by . This book was released on 2009 with total page 1240 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Ecological Regions of North America written by and published by . This book was released on 1997 with total page 92 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume represents a first attempt at holistically classifying and mapping ecological regions across all three countries of the North American continent. A common analytical methodology is used to examine North American ecology at multiple scales, from large continental ecosystems to subdivisions of these that correlate more detailed physical and biological settings with human activities on two levels of successively smaller units. The volume begins with an overview of North America from an ecological perspective, concepts of ecological regionalization. This is followed by descriptions of the 15 broad ecological regions, including information on physical and biological setting and human activities. The final section presents case studies in applications of the ecological characterization methodology to environmental issues. The appendix includes a list of common and scientific names of selected species characteristic of the ecological regions.

Download or read book Climate Change and Oregon written by and published by . This book was released on 1998 with total page 4 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 2001 with total page 812 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Ecology Abstracts written by and published by . This book was released on 1998 with total page 566 pages. Available in PDF, EPUB and Kindle. Book excerpt: Coverage: 1982- current; updated: monthly. This database covers current ecology research across a wide range of disciplines, reflecting recent advances in light of growing evidence regarding global environmental change and destruction. Major ares of subject coverage include: Algae/lichens, Animals, Annelids, Aquatic ecosystems, Arachnids, Arid zones, Birds, Brackish water, Bryophytes/pteridophytes, Coastal ecosystems, Conifers, Conservation, Control, Crustaceans, Ecosyst em studies, Fungi, Grasses, Grasslands, High altitude environments, Human ecology, Insects, Legumes, Mammals, Management, Microorganisms, Molluscs, Nematodes, Paleo-ecology, Plants, Pollution studies, Reptiles, River basins, Soil, TAiga/tundra, Terrestrial ecosystems, Vertebrates, Wetlands, Woodlands.