Forest management is a complex process that now incorporates information obtained from many sources. It is increasingly obvious that the physiological status of the trees in a forest has a dramatic impact on the likely success of any particular management strategy. Indeed, models described in this book that deal with forest productivity and sustainability require physiological information. This information can only be obtained from an understanding of the basic biological mechanisms and processes that contribute to individual tree growth. This valuable book illustrates that physiological ecology is a fundamental element of proficient forest management.

Even though most of the biomass of the planet is in forests, we live in a world where wood as a raw material and its products are increasingly scarce. This is particularly so in important areas such as the European Community, which is far from self-sufficient in terms of wood. In recent years the need to intensify forest production and, in some cases, to uti lize abandoned agricultural land for forestry has focussed world-wide attention on the economic importance of fast-growing tree plantations. These are usually managed as short "rotations" (growing cycles) of less than 15 years, often for the production of industrial raw materials or biomass for energy. Under the designation of fast-growing tree plantations, or short rotation silviculture, one may find ecosystems managed for different economic objectives, with different intensities of technical intervention and different levels of productivity. They may include any of a wide range of species grown under various environmental conditions. A common factor, however, is the greater possibility that exists, relative to conventional forestry, for manipulation of both the environment and the genetics of the trees."

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.

Even though most of the biomass of the planet is in forests, we live in a world where wood as a raw material and its products are increasingly scarce. This is particularly so in important areas such as the European Community, which is far from self-sufficient in terms of wood. In recent years the need to intensify forest production and, in some cases, to uti lize abandoned agricultural land for forestry has focussed world-wide attention on the economic importance of fast-growing tree plantations. These are usually managed as short "rotations" (growing cycles) of less than 15 years, often for the production of industrial raw materials or biomass for energy. Under the designation of fast-growing tree plantations, or short rotation silviculture, one may find ecosystems managed for different economic objectives, with different intensities of technical intervention and different levels of productivity. They may include any of a wide range of species grown under various environmental conditions. A common factor, however, is the greater possibility that exists, relative to conventional forestry, for manipulation of both the environment and the genetics of the trees."