Offering an enlightening perspective of the root-soil interface, this collection of electron micrographs demonstrates the dynamic nature of the root surface as cells differentiate, function, and age.

The Soil-Root Interface contains the proceedings of an international symposium held in Oxford, England, on March 28 to 31, 1978. The first five chapters of this book contain the majority of papers presented at the meeting, as well as the descriptions of displayed posters and films. Abstracts of other contributions offered by participants but not read at the meeting form the final chapter. The first five parts cover topics on nutrient demand and supply at the soil root interface; physics and chemistry of the interfacial region; biological activities at the interface; the interface in relation to environmental stress and disease; and the interface in relation to soil function and growth.

There is a scarcity of detailed information regarding the ecophysiology of root systems and the way root system functioning is affected by both internal and external factors. Furthermore, global climate change is expected to increase the intensity of climate extremes, such as severe drought, heat waves and periods of heavy rainfall; in addition other stresses such as salinization of soils are increasing world-wide. Recently an increasing awareness has developed that understanding plant traits will play a major role in breeding of future crop plants. For example, there is increasing evidence that the traits of root systems are defined by the properties of individual roots. However, further knowledge on the functional importance of root segments and the molecular/physiological mechanisms underlying root system functioning and persistence is needed, and would specifically allow modifying (crop) root system functionality and efficiency in the future. Another major gap in knowledge is localized at the root-soil interface and in regard to the potential adaptive plasticity of root-rhizosphere interactions under abiotic stress and/or competition. It is currently unknown whether adaptations in microbe communities occur, for example due to modified exudation rates, and what are the subsequent influences on nutrient mobilization and uptake. Furthermore, uncovering the mechanisms by which roots perceive neighboring roots may not only contribute to our understanding of plant developmental strategies, but also has important implications on the study of competitive interactions in natural communities, and in optimizing plant performance and resource use in agricultural and silvicultural systems. In this Research Topic, we aimed to provide an on-line, open-access snapshot of the current state of the art of the field of root ecology and physiology, with special focus on the translation of root structure to function, and how root systems are influenced by interplay with internal and external factors such as abiotic stress, microbes and plant-plant interaction. We welcomed original research papers, but reviews of specific topics, articles formulating opinions or describing cutting-edge methods were also gladly accepted.

First published in 1987 this book looks at root development and functions. Besides affecting the development of roots directly, the physical environment also influences the organisms associated with roots and thus affects their function. The papers presented in this volume pay equal attention to root development and root function in relation to the whole range of environmental factors including temperature, light, water, aeration, gravity and the mechanical strength of the soil. Consideration is also given to the effects of some of these factors on mycorrhizae and nitrogen-fixing bacteria. The final chapter reviews some of the main themes raised in the volume and indicates the way that research at the cellular and tissue levels may progress in the future.

Soil is a fundamental and critical component of terrestrial ecosystems, but one that is often overlooked. It is an extremely complex environment, both in terms of its physical structure and in that it supports levels of biodiversity far greater than those found above ground in any ecosystem. Bringing together existing knowledge across many areas of soil biology and physics, this book develops the concept of soil architecture and explores key characteristics of the remarkable `inner space' of the soil. The authors consider how such structure develops through time and the consequences this has for life underground. They also explore the interactions between the biological and physical components of the soil and how they relate to its many functions, in order to demonstrate the key role of soil architecture in underpinning ecosystem dynamics. The diverse but richly interrelated perspectives offered in this book make it an essential resource for researchers and students in soil and environmental sciences, terrestrial ecology, plant sciences and microbiology.

Some pioneers in soil research such as Müller and Kubiëna were as much biologists as they were soil scientists and the legendary biologist Charles Darwin was foresighted in recognizing the earthworms as instrumental in reworking the soil, thereby forming what he called "vegetable mould". Still, soil science has largely been the realm of physicists and chemists over the past decades. Whatever the reason, this picture is rapidly changing. Until recently, research on the transport and transformation of elements in soil was often concerned with either soil biota/plant relationships or with soil structure/plant relationships, if the biota were considered at all, but very few studies explicitly took the interrelationships between soil structure and soil biota into account. The conference on Soil Structure/Soil Biota Interrelationships, held at Wageningen, The Netherlands, 24-28 November 1991, was meant to bridge that gap, focussing on methods of research, organized in three levels: features, processes and effects. The proceedings of the conference are testimony of the need to intertwine the biological, morphological, physical and chemical disciplines in soil research to understand better and forecast soil properties and processes as related to land use for agricultural and other purposes. This book should be of particular interest to soil scientists and ecologists who feel the need for a cross-disciplinary approach in soils research. It should also be a rich source of teaching material for courses in soil science and soil ecology at graduate level and above, with ample reference to studies on land use as related to agriculture and the environment.