Allelochemicals play a great role in managed and natural ecosystems. Apart from plant growth, allelochemicals also may influence nutrient dynamics, mycorrhizae, soil chemical characteristics, and microbial ecology. Synergistic action of various factors may better explain plant growth and distribution in natural systems. The book emphasizes the role of allelochemicals in shaping the structure of plant communities in a broader ecological perspective. The book addresses the following questions: (1) How do allelochemicals influence different components of the ecosystem in terms of shaping community structure? (2) Why is it difficult to demonstrate interference by allelochemicals (i.e., allelopathy) in a natural system in its entirety? Despite a large amount of existing literature on allelopathy, why are ecologists still skeptical about the existence of allelopathy in nature? (3) Why are there only scarce data on aquatic ecosystems? (4) What role do allelochemicals play in microbial ecology?.....

Invasive plants have an impact on global biodiversity and ecosystem function, and their management is a complex task. The aim of this book is to discuss fundamental questions of invasion ecology, such as why particular communities become more invasible than others, what the mechanisms of exclusion of native species by invaders are, and whether invasion can be predicted. In addition, agricultural practices influencing invasion, the environmental and economic costs of invasion as well as possible management strategies are discussed. Readers will get a unique perspective on invasion ecology through employing general principles of ecology to plant invasions.

Chemical Ecology is a component of Encyclopedia of Chemical Sciences, Engineering and Technology Resources in the global Encyclopedia of Life Support Systems (EOLSS), which is an integrated compendium of twenty one Encyclopedias. The Theme on Chemical Ecology provides the essential aspects of the chemicals involved in the interactions of living organisms. It deals with studies involving defensive chemicals which are utilized to deter potential predators, which may attack a wide variety of species, animal interaction, aquatic ecosystems, chemical ecology and pest management, relation to medicine and pharmaceuticals. This volume is aimed at the following five major target audiences: University and College students Educators, Professional practitioners, Research personnel and Policy analysts, managers, and decision makers.

The increase in organic farming and concerns about potential negative effects on human health and the environment is creating a demand for pesticide-free food and alternative weed management techniques. This book provides a comprehensive examination of non-chemical weed management.

In the last decade, enormous progress has been made on the physiology of plant roots, including on a wide range of molecular aspects. Much of that progress has been captured in the chapters of this book. Breakthroughs have been made possible through integration of molecular and whole-plant aspects. The classical boundaries between physiology, biochemistry and molecular biology have vanished. There has been a strong focus on a limited number of model species, including Arabidopsis thaliana. That focus has allowed greater insight into the significance of specific genes for plant development and functioning. However, many species are very different from A. thaliana, in that they are mycorrhizal, develop a symbiosis with N2-fixing microsymbionts, or have other specialised root structures. Also, some have a much greater capacity to resist extreme environments, such as soil acidity, salinity, flooding or heavy-metal toxicities, due to specific adaptations. Research on species other than A. thaliana is therefore pivotal, to develop new knowledge in plant sciences in a comprehensive manner. This fundamental new knowledge can be the basis for important applications in, e.g., agriculture and plant conservation. Although significant progress has been made, much remains to be learnt. It is envisaged that discoveries made in the recent past will likely lead to major breakthroughs in the next decade.

This book provides the reader relevant information about actual knowledge about the process of allelopathy, covering all aspects from the molecular to the ecological level. Special relevance is given to the physiological and ecophysiological aspects of allelopathy. Several ecosystems are studied and methodological considerations are taken into account in several different chapters. The book has been written to be useful both for Ph.D. students and for senior researchers, so the chapters include all necessary information to be read by beginners, but they also include a lot of useful information and discussion for the initiated.

Providing the theoretical and conceptual framework for this continually evolving field, Agroecology: The Ecology of Sustainable Food Systems, Second Edition explores environmental factors and complexities affecting agricultural crops and animals. Completely revised, updated, and reworked, the second edition contains new data, new readings, new issues and case studies, and new options. It includes two completely new chapters, one on the role of livestock animals in agroecosystems and one on the cultural and community aspects of sustainable food systems. The author clearly delineates the importance of using an ecosystem framework for determining if a particular agricultural practice, input, or management decision contributes or detracts from sustainability. He explains how the framework provides the ecological basis for the functioning of the chosen management strategy over the long-term. He also examines system level interactions, stressing the need for understanding the emergent qualities of populations, communities, and ecosystems and their roles in sustainable agriculture. Using examples of farming systems in a broad array of ecological conditions, the book demonstrates how to use an ecosystem approach to design and manage agroecosystems for sustainability.