Genetic Response Of Forest Systems To Changing Environmental Conditions

Changing environmental conditions substantially affect genetic variation and its dynamics in forest ecosystems and various systems of plantations. In response to these challenges, the present book focuses on the response to stress in terms of case studies which address physiological and genetic characters as well as various metric traits. Furthermore a choice of studies is presented which refers to diversity and geographic variation of various species and site conditions, respectively. In addition, genetic resources are characterised and a variety of studies is compiled which address reproduction and migration as well as management aspects. Finally, a set of studies is presented which focus on forest tree breeding with respect to uncertain climatic futures.

During the 4th International Consultation on Forest Genetics and Tree Building, held in 1998 in Beijing, China, leading scientists were invited to review past achievements, to redefine the role of forest genetics and breeding in contemporary forestry, and to set priorities for future research and development. On the basis of the invited presentations, the volume summarizes the state of knowledge in various fields, such as the impact of forest management and of changing environmental conditions on genetic resources, and the value of genetic markers as indicators for adaptational potential, as well as the tasks of conservation. Detailed reports from the different continents provide a comprehensive diagnosis of the global situation of forest genetics and tree breeding research. The book offers not only an overview of contemporary trends and expected future developments, but also identifies current main problems in funding and cooperation. It may prove therefore useful not only for scientists, university lecturers and advanced students in the field of forestry, ecology and conservation biology, but also for decision makers and managers in companies and conservation organizations.

Trees are among the longest-living organisms. They are sensitive to extreme climatic events and document the effects of environmental changes in form of structural modifications of their tissues. These modifications represent an integrated signal of complex biological responses enforced by the environment. For example, temporal change in stem increment integrates multiple information of tree performance, and wood anatomical traits may be altered by climatic extremes or environmental stress. Recent developments in preparative tools and computational image analysis enable to quantify changes in wood anatomical features, like vessel density or vessel size. Thus, impacts on their functioning can be related to climatic forcing factors. Similarly, new developments in monitoring (cambial) phenology and mechanistic modelling are enlightening the interrelationships between environmental factors, wood formation and tree performance and mortality. Quantitative wood anatomy is a reliable indicator of drought occurrence during the growing season, and therefore has been studied intensively in recent years. The variability in wood anatomy not only alters the biological and hydraulic functioning of a tree, but may also influence the technological properties of wood, with substantial impacts in forestry. On a larger scale, alterations of sapwood and phloem area and their ratios to other functional traits provide measures to detect changes in a tree’s life functions, and increasing risk of drought-induced mortality with possible impacts on hydrological processes and species composition of plant communities. Genetic variability within and across populations is assumed to be crucial for species survival in an unpredictable future world. The magnitude of genetic variation and heritability of adaptive traits might define the ability to adapt to climate change. Is there a relation between genetic variability and resilience to climate change? Is it possible to link genetic expression and climate change to obtain deeper knowledge of functional genetics? To derive precise estimates of genetic determinism it is important to define adaptive traits in wood properties and on a whole-tree scale. Understanding the mechanisms ruling these processes is fundamental to assess the impact of extreme climate events on forest ecosystems, and to provide realistic scenarios of tree responses to changing climates. Wood is also a major carbon sink with a long-term residence, impacting the global carbon cycle. How well do we understand the link between wood growth dynamics, wood carbon allocation and the global carbon cycle? Papers contribution to this Research Topic will cover a wide range of ecosystems. However, special relevance will be given to Mediterranean-type areas. These involve coastal regions of four continents, making Mediterranean-type ecosystems extremely interesting for investigating the potential impacts of global change on growth and for studying responses of woody plants under extreme environmental conditions. For example, the ongoing trend towards warmer temperatures and reduced precipitation can increase the susceptibility to fire and pests. The EU-funded COST Action STREeSS (Studying Tree Responses to extreme Events: a SynthesiS) addresses such crucial tree biological and forest ecological issues by providing a collection of important methodological and scientific insights, about the current state of knowledge, and by opinions for future research needs.

Genetic resources for food and agriculture play a crucial role in food security, nutrition and livelihoods and in the provision of environmental services. They are key components of sustainability, resilience and adaptability in production systems. They underpin the ability of crops, livestock, aquatic organisms and forest trees to withstand a range of harsh conditions. Climate change poses new challenges to the management of the world's genetic resources for food and agriculture, but it also underlines their importance. At the request of the Commission on Genetic Resources for Food and Agriculture, FAO prepared thematic studies on the interactions between climate change and plant, animal, forest, aquatic, invertebrate and micro-organism genetic resources. This publication summarizes the results of these studies.

The forest ecosystem is the largest terrestrial ecosystem on earth. It not only has the highest biological productivity and the strongest ecological effect, but can also maintain carbon and oxygen balance and control temperature rise. With the rapid development of the economy, climate change has become the largest challenge to the continuation of forest ecosystem. With constantly changing climate, environmental conditions including CO2 concentration,temperature,intensity of rainfall and the probability of extreme weathers are all affected. In particular, extreme heat, extreme drought and intense fall will become more frequent and widespread. Climate change has a great impact on all ecosystems, especially forest ecosystems. As the largest carbon pool on the earth, these area play a very important role in mitigating global climate change. It is necessary to understand what changes have taken place in the growth and development of trees under climate change, the changes that have taken place in the regulation mechanism of trees when multiple stresses occur at the same time, and to determine the regulation mechanism of trees under new stresses? This book presents relevant results from scientific research in the fields of forest tree gene regulation in response to abiotic and biotic stresses that can contribute to the understanding of forest response mechanisms to different environmental signals and provide a new insight for tolerant tree improvement.

The forest ecosystem is the largest terrestrial ecosystem on earth. It not only has the highest biological productivity and the strongest ecological effect, but can also maintain carbon and oxygen balance and control temperature rise. With the rapid development of the economy, climate change has become the largest challenge to the continuation of forest ecosystem. With constantly changing climate, environmental conditions including CO2 concentration, temperature, intensity of rainfall and the probability of extreme weathers are all affected. In particular, extreme heat, extreme drought and intense fall will become more frequent and widespread. Climate change has a great impact on all ecosystems, especially forest ecosystems. As the largest carbon pool on the earth, these area play a very important role in mitigating global climate change. It is necessary to understand what changes have taken place in the growth and development of trees under climate change, the changes that have taken place in the regulation mechanism of trees when multiple stresses occur at the same time, and to determine the regulation mechanism of trees under new stresses? This book presents relevant results from scientific research in the fields of forest tree gene regulation in response to abiotic and biotic stresses that can contribute to the understanding of forest response mechanisms to different environmental signals and provide a new insight for tolerant tree improvement.