Physiology Of Trees

Growth and development. Ecological responses. Special topics and applications.

This book presents the latest information on tropical tree physiology, making it a valuable research tool for a wide variety of researchers. It is also of general interest to ecologists (e.g. Ecological Society of America; > 3000 or 4000 members at annual meeting), physiologists (e.g. American Society of Plant Biologists; > 2,000 members at annual meeting), and tropical biologists (e.g. Association for Tropical Biology and Conservation, ATBC; > 500 members at annual meeting). (American Geophysical Union(AGU), > 20000 members at annual meeting). Since plant physiology is taught at every university that offers a life sciences, forestry or agricultural program, and physiology is a focus at research institutes and agencies worldwide, the book is a must-have for university and research institution libraries.

Growth and structure. Photosynthesis. Carbohydrate metabolism. Nitrogen relations of trees. Fats, oils, terpenes, and related substances. Assimilation and respiration. Translocation and accumulation. Mineral nutrition and sakt absorption. Water relation and transpiration. Absorption of water and ascent of sap. Internal water relations. Reproduction. Physiology of seeds and seed germination. Internal factors afecting growth. Environmental factors affecting growth.

This publication comprises the proceedings of the first International Conference devoted to the structural roots of trees and woody plants. 'The Supporting Roots - Structure and Function,' 20-24 July 1998, Bordeaux, France. The meeting was held under the auspices ofIUFRO WPS 2. 01. 13 'Root Physiology and Symbiosis,' and its aim was to bring together scientific researchers, foresters and arboriculturalists, to discuss current problems in structural root research and disseminate knowledge to an audience from a wide disciplinary background. For the first time in an international conference, emphasis was placed on presenting recent reseach in the field of tree anchorage mechanics and root biomechanics. The way in which tree stability can be affected by root system symmetry and architecture was addressed, as well as how movement during wind sway can influence the development and shape of woody roots. The role of different nursery and planting techniques was discussed, in relation to effects on root system form and development. Root response to different environmental stresses, including water, temperature, nutrient and mechanical stress was addressed in detail. The structure and function of woody roots was also considered at different levels, from coarse to fine roots, with several papers discussing the interaction between roots and the rhizosphere. One of the conference highlights was the presentation of new methods in root research, by a series of workshops held at LRBB-INRA, Pierroton, on the northern border of the Gascony forest.

In the European Alps the importance of forests as protection against ava lanches and soil erosion is becoming ever clearer with the continuing increase in population and development of tourism. The protective potential of the moun tain forests can currently only be partially realised because a considerable propor tion of high-altitude stands has been destroyed in historical times by man's extensive clearing ofthe forests. The forests still remaining are of limited effec tiveness, due to inadequate density of trees and over-maturity. Considerable efforts, however, are now being made in the Alps and other mountains of the globe to increase the high-altitude forested area through reforestation, to raise depressed timberlines, and to restore remaining protection forests using suit able silvicultural methods to their full protective value. This momentous task, if it is to be successful, must be planned on a sound foundation. An important prerequisite is the assembly of scientific facts con cerning the physical environment in the protection forest zone of mountains, and the course of various life processes of tree species occurring there. Since the introduction of practical field techniques it has been possible to investigate successfully the reaction of trees at various altitudes to recorded factors, and the extent to which they are adapted to the measured situations. Such ecophysio logical studies enable us to recognize the site requirements for individual tree species, and the reasons for the limits of their natural distribution.

Millions of trees live and grow all around us, and we all recognize the vital role they play in the world’s ecosystems. Publicity campaigns exhort us to plant yet more. Yet until recently comparatively little was known about the root causes of the physical changes that attend their growth. Since trees typically increase in size by three to four orders of magnitude in their journey to maturity, this gap in our knowledge has been a crucial issue to address. Here at last is a synthesis of the current state of our knowledge about both the causes and consequences of ontogenetic changes in key features of tree structure and function. During their ontogeny, trees undergo numerous changes in their physiological function, the structure and mechanical properties of their wood, and overall architecture and allometry. This book examines the central interplay between these changes and tree size and age. It also explores the impact these changes can have, at the level of the individual tree, on the emerging characteristics of forest ecosystems at various stages of their development. The analysis offers an explanation for the importance of discriminating between the varied physical properties arising from the nexus of size and age, as well as highlighting the implications these ontogenetic changes have for commercial forestry and climate change. This important and timely summation of our knowledge base in this area, written by highly respected researchers, will be of huge interest, not only to researchers, but also to forest managers and silviculturists.