Download or read book A Method for Estimating Canopy Openness Effective Leaf Area Index and Photosynthetically Active Photon Flux Density Using Hemispherical Photography and Computerized Image Analysis Techniques written by G. W. Frazer and published by . This book was released on 1997 with total page 92 pages. Available in PDF, EPUB and Kindle. Book excerpt: Hemispherical canopy photography is an indirect method for measuring various components of forest canopy structure and solar radiation flux within and below forest canopies. The method utilizes a 180-degree fisheye-lens camera to capture and record the position, size, and shape of openings or gaps in a forest canopy. During late summer 1995, eight sites on southern Vancouver Island were intensively sampled using hemispherical photographic methods. This document describes the general theory, approach, and analytical tools associated with hemispherical canopy photography and computerized image analysis in the context of this research. As a result, a technical protocol has been devised that can be adopted, modified, and improved upon by those interested in using hemispherical techniques for similar research initiatives. Recommendations are made to improve the quality and reliability of future hemispherical image analysis systems. Appendices include information on measurement of fisheye lens distortion and the effect on the calculation of gap fraction magnitude and distribution, and a model for estimating percent open sky and leaf area index.
Download or read book Hemispherical Photography in Forest Science Theory Methods Applications written by Richard A. Fournier and published by Springer. This book was released on 2017-05-11 with total page 313 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents practical information about hemispherical photography from the perspectives of field data acquisition, image processing and information retrieval methods. This book is organized into three sections. The first section describes what is hemispherical photography and what are the fundamental elements of forest structure and light interactions within the forest canopy. The second section provides practical information about the equipment, procedures and tools for procuring, processing and analyzing hemispherical photographs. Armed with this information, the third section describes several applications of hemispherical photographs to forestry and natural resource assessment. The book concludes with a discussion about modelling tools and future directions of this rapidly growing field. There is currently no information source on the market that has this comprehensive range of topics combined in a single book. The book will appeal to academics, graduate students, natural resource professionals and researchers alike.
Download or read book Remote Sensing of Forest Environments written by Michael A. Wulder and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 535 pages. Available in PDF, EPUB and Kindle. Book excerpt: Remote Sensing of Forest Environments: Concepts and Case Studies is an edited volume intended to provide readers with a state-of-the-art synopsis of the current methods and applied applications employed in remote sensing the world's forests. The contributing authors have sought to illustrate and deepen our understanding of remote sensing of forests, providing new insights and indicating opportunities that are created when forests and forest practices are considered in concert with the evolving paradigm of remote sensing science. Following background and methods sections, this book introduces a series of case studies that exemplify the ways in which remotely sensed data are operationally used, as an element of the decision-making process, and in the scientific study of forests. Remote Sensing of Forest Environments: Concepts and Case Studies is designed to meet the needs of a professional audience composed of both practitioners and researchers. This book is also suitable as a secondary text for graduate-level students in Forestry, Environmental Science, Geography, Engineering, and Computer Science.
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 Remote Sensing for Sustainable Forest Management written by Steven E. Franklin and published by CRC Press. This book was released on 2001-06-13 with total page 425 pages. Available in PDF, EPUB and Kindle. Book excerpt: As remote sensing data and methods have become increasingly complex and varied - and increasingly reliable - so have their uses in forest management. New algorithms have been developed in virtually every aspect of image analysis, from classification to enhancements to estimating parameters. Remote Sensing for Sustainable Forest Management reviews t
Download or read book Information Report written by and published by . This book was released on 1985 with total page 498 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Evaluation of Forest Canopies by Photography written by Philip L. Johnson and published by . This book was released on 1968 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt: A technique for evaluating forest canopies was developed based on the use of a divergent lens system to obtain hemispherical photographs of tree crowns. The photography was processed from 35 mm film and enlarged as a silhouette, and the light transmission was measured with a specially fabricated macrodensitometer. It is shown by application to a variety of problems in diverse geographical areas that this technique can be used for measuring both temporal and spatial changes in the canopy, for estimating the shade light climate, and for specifying the probability of target detection through a canopy. Data are presented to analyze changes caused by explosions, radioactivity, growing season, and vegetation types. The geometry of gaps in three crowns is discussed and the nature of shade light quality under forests is illustrated. (Author).
Download or read book Lite a Model for Estimating Light Interception and Transmission Through Forest Canopies written by and published by . This book was released on 1998 with total page 100 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Photosynthesis of Leaf Canopies written by Cornelis Teunis de Wit and published by . This book was released on 1965 with total page 68 pages. Available in PDF, EPUB and Kindle. Book excerpt: The development of a procedure to calculate the effect of certain environmental factors on the rate of photo-synthesis imposed mainly geometrical problems, which were solved in such a way that the actual calculation could be carried out by means of a computer. The calculation procedures have been used to study the. relative importance of the variables under various conditions. The results for a standard set of conditions, have been summarized in order to make it possible to estimate the daily photosynthesis at any time and place for a wide range of photosynthesis functions without a computer.
Download or read book Plant Canopies written by Society for Experimental Biology (Great Britain). Meeting and published by Cambridge University Press. This book was released on 1989 with total page 192 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume is a synthesis of current knowledge about the growth, development and functioning of plant canopies.
Download or read book Canopy Photosynthesis From Basics to Applications written by Kouki Hikosaka and published by Springer. This book was released on 2015-12-17 with total page 450 pages. Available in PDF, EPUB and Kindle. Book excerpt: The last 30 years has seen the development of increasingly sophisticated models that quantify canopy carbon exchange. These models are now essential parts of larger models for prediction and simulation of crop production, climate change, and regional and global carbon dynamics. There is thus an urgent need for increasing expertise in developing, use and understanding of these models. This in turn calls for an advanced, yet easily accessible textbook that summarizes the “canopy science” and introduces the present and the future scientists to the theoretical background of the current canopy models. This book presents current knowledge of functioning of plant canopies, models and strategies employed to simulate canopy function, and the significance of canopy architecture, physiology and dynamics in ecosystems, landscape and biosphere.
Download or read book Leaf Area Index and Specific Leaf Weight written by Ram Oren and published by . This book was released on 1984 with total page 158 pages. Available in PDF, EPUB and Kindle. Book excerpt: Two physiological factors are of major importance to tree and stand growth: (1) the photosynthetic rate of foliage and (2) the amount of foliage. If carbohydrate allocation patterns remain constant, stand growth should be related directly to total canopy photosynthesis. From a literature analysis I assess methods of relating photosynthetic rates to biochemical, anatomical, and structural characteristics of foliage. A number of these foliage characteristics were found to be interrelated. Specific leaf weight was shown to be a valuable index for comparing photosynthesis by various parts of a tree canopy over a season or throughout an entire year. Mean annual photosynthetic rate in five separate portions of a spruce canopy was directly proportional to observed differences in specific leaf weight (r2 = 0.99). Annual carbon uptake was a function of total foliage biomass (r2 = 0.96). When foliage biomass at each crown segment was adjusted for differences in specific leaf weight, reflecting differences in photosynthetic rates, the predictive equation further improved C r2 = 0.99). Specific leaf weight is recommended as an index for comparing the relative effects of various silvicultural treatments on photosynthesis. I then evaluated how stand growth and canopy leaf area were related by analyzing 24 years of growth records from a Pinus ponderosa (Laws.) experiment. The experiment included a wide range in initial stocking and partial control of understory vegetation (Barrett 1982). I found that treatment effects on tree growth can be evaluated at low values of stand leaf area from comparison of growth efficiencies (wood produced per unit leaf area) among plots of similar canopy leaf area. By comparing stand growth with stand leaf area, I concluded that the major effect of removing understory vegetation was to speed the development of the canopy. This interpretation was also supported by a comparison of the rate of leaf area development on plots with and without understory vegetation at comparable levels of canopy leaf area. Comparing stands at a similar canopy leaf area is advised for assessing how treatment affects stand development. This is a valuable alternative to analyzing treatment effects at one point in time and helps to explain the results of many fertilization experiments.
Download or read book A Vegetation Canopy Radiative Transfer Model and Its Use to Estimate Canopy Leaf Area Index and Absorbed Fraction of Photosynthetically Active Radiation written by Mauro Antonio Homem Antunes and published by . This book was released on 1997 with total page 362 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Photosynthesis and Production in a Changing Environment written by D.O. Hall and published by Springer Science & Business Media. This book was released on 2013-12-01 with total page 503 pages. Available in PDF, EPUB and Kindle. Book excerpt: The majority of the world's people depend research work should be carried out at the local and regional level by locally trained on plants for their livelihood since they grow them for food, fuel, timber, fodder and people. many other uses. A good understanding Following the success of our earlier book of the practical factors which govern the (Techniques in Bioproductivity and Photo synthesis; Pergamon Press, 1985), which productivity of plants through the process of photosynthesis is therefore of paramount was translated into four major languages, importance, especially in the light of cur the editors and contributors have exten rent concern about global climate change sively revised the content and widened the and the response of both crops and natural scope of the text,· so it now bears a title ecosystems. in line with current concern over global The origins of this book lie in a series of climate change. · In particular, we have training courses sponsored by the United added chapters on remote sensing, con Nations Environment Programme (Project trolled-environment studies, chlorophyll No. FP/6108-88-0l (2855); 'Environment fluorescence, metabolite partitioning and changes and the productivity of tropical the use of mass isotopes, all of which grasslands'), with additional support from techniques are increasing in their applica many international and national agencies. tion and importance to this subject area.
Download or read book Terrain Feature Canopy Modeling written by D. S. Kimes and published by . This book was released on 1979 with total page 206 pages. Available in PDF, EPUB and Kindle. Book excerpt: A thermal canopy signature model (TCSM) was developed to approximate the thermal behavior of a vegetation canopy by a mathematical abstraction of three horizontal layers of vegetation. Canopy geometry within each layer is quantitatively described by the foliage and branch orientation distributions. Canopy geometry, solar irradiance, air temperature, horizontal wind velocity, relative humidity, and ground temperature are used to calculate the energy budgets of average leaves within each layer. The resulting system of conservation equations is solved for the average layer temperature. This information, together with the angular distributions of radiating elements, is then used to calculate the thermal exitance as a function of view angle above the canopy. Optical diffraction techniques were developed and employed to measure canopy geometry. Solar radiation absorption with the vegetation terrain elements is calculated using a modification of a Monte Carlo model (SRVC) developed for the reflective energy regime. The models were applied to a lodgepole pine (Pinus contorta) canopy and the results for a diurnal cycle are validated with radiometric measurements. Simulated versus measured radiometric average temperatures of Layer 2 correspond approximately within two degrees centigrade. Simulated results suggest that canopy geometry can significantly influence the effective radiant temperature recorded by a sensor above the canopy as a function of view angle. (Author).
Download or read book Ecology and Decline of Red Spruce in the Eastern United States written by Mary B. Adams and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 427 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the early 1980s there were several published reports of recent, unexplained increases in mortality of red spruce in the Adirondack Mountains and the northern Appalachian Mountains of the eastern United States. These reports coincided with documentation of reductions in radial growth of several species of pine in the southeastern United States, and with the severe, rapid, and widespread decline of Norway spruce, silver fir, and some hardwoods in central Europe. In all of these instances, atmospheric deposition was hypothesized as the cause of the decline. (Throughout this volume, we use the term "decline" to refer to a loosely synchronized regional-scale deterioration of tree health which is brought about by a combination of stress factors. These may be biotic or abiotic in nature, and the combinations may differ from site to site. ) Heated public debate about the causes and possible cures for these forest declines ensued. Through the course of this debate, it became clear that information about forest health and air pollution effects on forests was inadequate to meet policymakers' needs. Ecology and Decline of Red Spruce in the Eastern United States addresses that gap for eastern spruce fir forests and represents the culmination of a great deal of research conducted in recent years. The focus is on red spruce because the decline of red spruce was both dramatic and inexplicable and because of the great amount of information gathered on red spruce.
Download or read book Abr g Des Publications written by Canadian Forest Service and published by . This book was released on 1997 with total page 64 pages. Available in PDF, EPUB and Kindle. Book excerpt: