Mycorrhizal Dynamics In Ecological Systems

Interdisciplinary volume on dynamic interactions between plants and fungi and how they scale up to land management and global change.

This multi-authored book gives an overview of recent advances and breakthroughs in the field of mycorrhizal ecology. The text elucidates mechanisms that determine plant biodiversity - a prerequisite to ensuring successful management for the conservation and restoration of ecosystems. Topics covered include: all the major mycorrhizal types, plant population biology, multitrophic interactions, biological diversity, ecosystem functioning, global change and evolution. This volume shows that collaboration in the rhizosphere is essential for plants, microbes, plant communities and ecosystems. It has been written with ecologists in mind, giving them easy access to an understanding of how these important interactions could shape our ecosystems.

The last 25 years have seen significant advances in our understanding of the mycorrhizal fungi that colonize most of the world’s plants, and the mycorrhizal networks that form and extend into the soil beyond plant roots. In addition to a thorough review of recent research on mycorrhizal networks, this book provides readers with alternative perspectives. The book is organized into three sections: Network Structure, Nutrient Dynamics, and the Mutualism-Parasitism Continuum. Chapter 1 addresses the specificity of ectomycorrhizal symbionts and its role in plant communities, and provides an updated list of terms and definitions. Chapter 2 explores interactions between symbionts in mycorrhizal fungi networks, as well as interactions between fungal individuals. The second section of the book begins with the examination in Chapter 3 of extramatrical mycelium (mycelia beyond the root tips) in ectomycorrhizal fungi, focused on carbon and nitrogen. Chapter 4 reviews the influence of mycorrhizal networks on outcomes of plant competition in arbuscular mycorrhizal plant communities. Chapter 5 discusses nutrient movement between plants through networks with a focus on the magnitude, fate and importance of mycorrhiza-derived nutrients in ectomycorrhizal plants. Section 3 opens with a review of research on the role of ectomycorrhizal networks on seedling establishment in a primary successional habitat, in Chapter 6. The focus of Chapter 7 is on facilitation and antagonism in arbuscular mycorrhizal networks. Chapter 8 explores the unique networking dynamic of Alnus, which differs from most ectomycorrhizal plant hosts in forming isolated networks with little direct connections to networks of other host species in a forest. Chapter 9 argues that most experiments have not adequately tested the role of mycorrhizal networks on plant community dynamics, and suggests more tests to rule out alternative hypotheses to carbon movement between plants, especially those that include experimental manipulations of the mycorrhizal networks. Plant ecologists have accumulated a rich body of knowledge regarding nutrient acquisition by plants. The editor proposes that research indicating that mycorrhizal fungi compete for nutrients, which are then delivered to multiple hosts through mycorrhizal networks, represents an important new paradigm for plant ecologists.

"Ecosystem" is an intuitively appealing concept to most ecologists, but, in spite of its widespread use, the term remains diffuse and ambiguous. The authors of this book argue that previous attempts to define the concept have been derived from particular viewpoints to the exclusion of others equally possible. They offer instead a more general line of thought based on hierarchy theory. Their contribution should help to counteract the present separation of subdisciplines in ecology and to bring functional and population/community ecologists closer to a common approach. Developed as a way of understanding highly complex organized systems, hierarchy theory has at its center the idea that organization results from differences in process rates. To the authors the theory suggests an objective way of decomposing ecosystems into their component parts. The results thus obtained offer a rewarding method for integrating various schools of ecology.

Ectomycorrhizal symbiosis plays a major role in biodiversity and stability of ecosystems in tropical forests. It is a research imperative in tropical and neotropical forest ecosystems because they contain ecologically and economically important tree species. This book provides an overview of the knowledge of ECM symbioses in tropical and neotropical ecosystem forests. The contents address diversity and function of ectomycorrhiza associated with forest plants, impacts of ectomycorrhiza on plant diversity and composition, regeneration and dynamics of ecosystems, biomass production in forestry, and adaptation of ectomycorrhiza.

Ecologists are aware of the importance of natural dynamics in ecosystems. Historically, the focus has been on the development in succession of equilibrium communities, which has generated an understanding of the composition and functioning of ecosystems. Recently, many have focused on the processes of disturbances and the evolutionary significance of such events. This shifted emphasis has inspired studies in diverse systems. The phrase "patch dynamics" (Thompson, 1978) describes their common focus. The Ecology of Natural Disturbance and Patch Dynamics brings together the findings and ideas of those studying varied systems, presenting a synthesis of diverse individual contributions.

This book is a consideration of the dynamics of forested systems at the time and spatial scales that 1 feel are implied by our present-day use of the term "succession." The investigation will be conducted by exercising a set of ecological models called "gap models," which have been in a state of development and improvement for the past 15 years. It is the intent of this book to use these models as tools for exploring theories of ecological succession. Ecological succession is one of the most obvious and demonstrable features of natural systems when viewed from outside the field of ecology. Succession is used by teachers as a theory that introduces young people to the interactive and dynamic nature of ecosystems. Succession theory and examples of succession are proclaimed from legions of nature trail guidebooks and placards. It is a pleasant classroom exercise to discuss how ecological systems change as the product of internal mechanisms that can be demonstrated by observaaon. The deductive explanation of how a particular place came to have a given assemblage of tree species has a pleasing "Sherlock Holmesian" touch that can be challenging to puzzle through.

Mycorrhizal symbioses are central to the multitrophic interactions that impact plant productivity, competitiveness and survival. This book integrates present-day knowledge from well-known research groups on some of the topics which are at the forefront of mycorrhizal research. Topics include the cell programmes that drive mycorrhiza formation and function, the processes sustaining symbiotic mutualism, stress response mechanisms in mycorrhizal symbionts, and the diversity and ecological impacts of mycorrhizal systems. The efficient management of mycorrhizal systems has the potential to support the sustainable production of quality foods while ensuring environmental quality for future generations.