Disturbance And Ecosystems

The earth's landscapes are being increasingly impacted by the activities of man. Unfortunately, we do not have a full understanding of the consequences of these disturbances on the earth's productive capacity. This problem was addressed by a group of French and U.S. ecologists who are specialists at levels of integration extending from genetics to the biosphere at a meeting at Stanford, California, sponsored by the National Science Foundation and the Centre National de la Recherche Scientifique. With a few important exceptions it was found at this meeting that most man-induced disturbances of ecosystems can be viewed as large scale patterns of disturbances that have occurred, generally on a small scale, in ecosystems through evolutionary time. Man has induced dramatic large-scale changes in the environment which must be viewed at the biosphere level. Acid deposition and CO increase are two 2 examples of the consequences of man's increased utilization of fossil fuels. It is a matter of considerable concern that we cannot yet fully predict the ecological consequences of these environmental changes. Such problems must be addressed at the international level, yet substantive mechanisms to do this are not available.

Disturbance ecology continues to be an active area of research, having undergone advances in many areas in recent years. One emerging direction is the increased coupling of physical and ecological processes, in which disturbances are increasingly traced back to mechanisms that cause the disturbances themselves, such as earth surface processes, mesoscale, and larger meteorological processes, and the ecological effects of interest are increasingly physiological. Plant Disturbance Ecology, 2nd Edition encourages movement away from the informal, conceptual approach traditionally used in defining natural disturbances and clearly presents how scientists can use a multitude of approaches in plant disturbance ecology. This edition includes nine revised chapters from the first edition, as well new, more comprehensive chapters on fire disturbance and beaver disturbance. Edited by leading experts in the field, Plant Disturbance Ecology, 2nd Edition is an essential resource for scientists interested in understanding plant disturbance and ecological processes. Advances understanding of natural disturbances by combining geophysical and ecological processes Provides a framework for collaboration between geophysical scientists and ecologists studying natural disturbances Includes fully updated research with 5 new chapters and revision of 11 chapters from the first edition

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.

Human impact on natural landscapes through urbanization and agricultural expansion are becoming more and more dramatic and are the cause of serious environmental problems. This volume examines the effect of landscape disturbance on plant and animal diversity in the five mediterranean-climate regions of the world. It begins with three introductory chapters broadly reviewing the issues of landscape degradation. Further contributions describe regional land use conflicts in each of the five regions. Landscape disturbance and plant diversity, and landscape disturbance and animal diversity are treated in separate chapters. Four contributions deal with demography and ecophysiology in vegetation succession following disturbance. The volume closes with a consideration of the future addressing aspects of environmental politics.

As the human population inexorably grows, its cumulative impact on the Earth's resources is hard to ignore. The ability of the Earth to support more humans is dependent on the ability of humans to manage natural resources wisely. Because disturbance alters resource levels, effective management requires understanding of the ecology of disturbance. This book is the first to take a global approach to the description of both natural and anthropogenic disturbance regimes that physically impact the ground. Natural disturbances such as erosion, volcanoes, wind, herbivory, flooding and drought plus anthropogenic disturbances such as foresty, grazing, mining, urbanization and military actions are considered. Both disturbance impacts and the biotic recovery are addressed as well as the interactions of different types of disturbance. Other chapters cover processes that are important to the understanding of disturbance of all types including soil processes, nutrient cycles, primary productivity, succession, animal behaviour and competition. Humans react to disturbances by avoiding, exacerbating, or restoring them or by passing environmental legislation. All of these issues are covered in this book. Managers need better predictive models and robust data-collections that help determine both site-specfic and generalized responses to disturbance. Multiple disturbances have a complex effect on both physical and biotic processes as they interact. This book provides a wealth of detail about the process of disturbance and recovery as well as a synthesis of the current state of knowledge about disturbance theory, with extensive documentation.

The Ecology of Natural Disturbance and Patch Dynamics brings together the findings and ideas of researchers studying such varied systems as marine invertebrate communities; grasslands; and boreal, temperate, and tropical forests. The primary goal is to present a synthesis of diverse individual contributions. The book is divided into three main sections: (1) examples of patch dynamics in diverse systems; (2) adaptations of organisms and evolution of populations in patch dynamic environments; and (3) implications of patch dynamics for the organization of communities and the functioning of ecosystems. This approach demonstrates the commonality of disturbance-generated phenomena over a wide range of scales and levels of organization, and thus validates the broad applicability of the patch dynamic viewpoint. The book presents a framework that can stimulate the generation of explicit hypotheses and theory and forms an alternative to equilibrium concepts of the evolution of populations, composition of communities, and functioning of ecosystems.

This book represents an introductory review of disturbance ecology and threat analysis, providing schematic concepts and approaches useful for work on sites that are affected by the impact of human actions. It is aimed at conservation and environmental practitioners, who will find tips for choosing methods and approaches when there are conflicts between the natural components and human activity. It is also addressed to students of applied ecology, ecosystem management, land-use planning and environmental impact assessment. It discusses a number of topics covered in the programs of many university courses related to basic ecology and ecology of disturbance, the latter constituting a field of great interest because of its implications and repercussions in applied territorial science. The book is divided into two parts: the first focuses on the theoretical and disciplinary framework of the ecology of disturbance, while the second is devoted to the analysis of anthropogenic threats. This, in particular, discusses the most recent approach, which uses a conventional nomenclature to allow a coarse-grained quantification and objective assessment of threat impact on different environmental components. Such an approach facilitates the comparison of hierarchically different events and, therefore, helps define the priorities for management and conservation strategies.

The advent of ecosystem ecology has created great difficulties for ecologists primarily trained as biologists, since inevitably as the field grew, it absorbed components of other disciplines relatively foreign to most ecologists yet vital to the understanding of the structure and function of ecosystems. From the point of view of the biological ecologist struggling to understand the enormous complexity of the biological functions within an ecosystem, the added necessity of integrating biology with geochemis try, hydrology, micrometeorology, geomorphology, pedology, and applied sciences (like silviculture and land use management) often has appeared as an impossible requirement. Ecologists have frequently responded by limiting their perspective to biology with the result that the modeling of species interactions is sometimes considered as modeling ecosystems, or modeling the living fraction of the ecosystems is considered as modeling whole ecosystems. Such of course is not the case, since understanding the structure and function of ecosystems requires sound understanding of inanimate as well as animate processes and often neither can be under stood without the other. About 15 years ago, a view of ecology somewhat different from most then prevailing, coupled with a strong dose of naivete and a sense of exploration, lead us to believe that consideration of the inanimate side of ecosystem function rather than being just one more annoying complexity might provide exceptional advantages in the study of ecosystems. To examine this possibility, we took two steps which occurred more or less simultaneously.