The efficient management of trees and other woody plants can be improved given an understanding of the physiological processes that control growth, the complex environmental factors that influence those processes, and our ability to regulate and maintain environmental conditions that facilitate growth. - Emphasizes genetic and environmental interactions that influence woody plant growth - Outlines responses of individual trees and tree communities to environmental stress - Explores cultural practices useful for efficient management of shade, forest, and fruit trees, woody vines, and shrubs

As sessile organisms, plants have to cope with a multitude of natural and anthropogenic forms of stress in their environment. Due to their longevity, this is of particular significance for trees. As a consequence, trees develop an orchestra of resilience and resistance mechanisms to biotic and abiotic stresses in order to support their growth and development in a constantly changing atmospheric and pedospheric environment. The objective of this Special Issue of Forests is to summarize state-of-art knowledge and report the current progress on the processes that determine the resilience and resistance of trees from different zonobiomes as well as all forms of biotic and abiotic stress from the molecular to the whole tree level.

Box 9E. 1 Continued FIGURE 2. The C–S–R triangle model (Grime 1979). The strategies at the three corners are C, competiti- winning species; S, stress-tolerating s- cies; R,ruderalspecies. Particular species can engage in any mixture of these three primary strategies, and the m- ture is described by their position within the triangle. comment briefly on some other dimensions that Grime’s (1977) triangle (Fig. 2) (see also Sects. 6. 1 are not yet so well understood. and 6. 3 of Chapter 7 on growth and allocation) is a two-dimensional scheme. A C—S axis (Com- tition-winning species to Stress-tolerating spe- Leaf Economics Spectrum cies) reflects adaptation to favorable vs. unfavorable sites for plant growth, and an R- Five traits that are coordinated across species are axis (Ruderal species) reflects adaptation to leaf mass per area (LMA), leaf life-span, leaf N disturbance. concentration, and potential photosynthesis and dark respiration on a mass basis. In the five-trait Trait-Dimensions space,79%ofallvariation worldwideliesalonga single main axis (Fig. 33 of Chapter 2A on photo- A recent trend in plant strategy thinking has synthesis; Wright et al. 2004). Species with low been trait-dimensions, that is, spectra of varia- LMA tend to have short leaf life-spans, high leaf tion with respect to measurable traits. Compared nutrient concentrations, and high potential rates of mass-based photosynthesis. These species with category schemes, such as Raunkiaer’s, trait occur at the ‘‘quick-return’’ end of the leaf e- dimensions have the merit of capturing cont- nomics spectrum.

Process-based models open the way to useful predictions of the future growth rate of forests and provide a means of assessing the probable effects of variations in climate and management on forest productivity. As such they have the potential to overcome the limitations of conventional forest growth and yield models, which are based on mensuration data and assume that climate and atmospheric CO2 concentrations will be the same in the future as they are now. This book discusses the basic physiological processes that determine the growth of plants, the way they are affected by environmental factors and how we can improve processes that are well-understood such as growth from leaf to stand level and productivity. A theme that runs through the book is integration to show a clear relationship between photosynthesis, respiration, plant nutrient requirements, transpiration, water relations and other factors affecting plant growth that are often looked at separately. This integrated approach will provide the most comprehensive source for process-based modelling, which is valuable to ecologists, plant physiologists, forest planners and environmental scientists. - Includes explanations of inherently mathematical models, aided by the use of graphs and diagrams illustrating causal interactions and by examples implemented as Excel spreadsheets - Uses a process-based model as a framework for explaining the mechanisms underlying plant growth - Integrated approach provides a clear and relatively simple treatment

This synthesis of the growing body of information from research on epiphytes and their relations with other tropical biota provides a comprehensive overview of basic functions, life history, evolution, and the place of epiphytes in complex tropical communities. Epiphytes comprise more than one-third of the tropical vascular flora in some tropical forests. Growing within tropical forest canopies, epiphytes are subject to severe environmental constraints, and their diverse adaptations make them a rich resource for studies of water balance, nutrition, reproduction and evolution.

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.