Landscape Ecology Principles in Landscape Architecture and Land-Use Planning

Copyright © 1996 President and Fellows of Harvard College

All rights reserved. No part of this publication may be reproduced without permission. The work herein is that of individual authors; it does not necessarily represent the views of Harvard University, the Graduate School of Design, or any of its programs.

Library of Congress Catalog Card Number 95-82343

9781610914673

Published by Harvard University Graduate School of Design,

Island Press and the American Society of Landscape Architects

Island Press, 1718 Connecticut Avenue, N.W., Suite 300,

Washington, DC 20009

Printed on recycled acid-free paper e9781610914673_i0002.jpg

Cover Photos:

Idaho, U.S.A., USDA Soil Conservation Service photo.

California, U.S.A., USDA Soil Conservation Service photo.

Massachusetts, U.S.A., R. Forman photo.

Cover Illustration:

James D. Olson and Richard T.T. Forman

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Table of Contents

Title Page

Copyright Page

FOREWORD

PREFACE AND ACKNOWLEDGMENTS

FOUNDATIONS

Part One: Principles

PATCHES

EDGES AND BOUNDARIES

CORRIDORS AND CONNECTIVITY

MOSAICS

Part Two: Practical Applications

OVERVIEW

SCHEMATIC APPLICATIONS

CASE STUDIES IN BRIEF

SUMMARY AND CONCLUSION

ADDITIONAL REFERENCES

FOREWORD

The thin mosaic, the tissue of the planet, is in upheaval. An urgent need exists for new tools and new language to understand how to live without losing nature. The solutions will be at the landscape scale—working with the larger pattern, understanding how it works, and designing in harmony with the structure of the natural system that sustains us all.

Each landscape has its own signature. This book will give you new eyes, and a means to communicate and collaborate with the many ecologists and landscape architects who are reaching out to work together and find cross-disciplinary solutions to land-use challenges.

Places are like large organisms, the products of natural forms and processes at work. Places are uniquely different and each possesses an intrinsic potential for change. This book will also help landscape architects and planners to work with communities that are inventing and formulating the new civics of sustainability.

What encourages me most about this book is how its principles are both simple and holistic in the way they tie together land, water, wildlife, and people. As designers and planners we must weave together this mosaic of patches and corridor networks, like a quilt held together with threads, to hold the landscape from falling apart. Understanding this mosaic will be our greatest challenge.

We need more succinct books like this one, with its simple tools and language, to couple the usually opposing forces of government regulations, economic self-interest, and the land ethic to run parallel.

Grant Jones, FASLA

Jones & Jones

Seattle, Washington

PREFACE AND ACKNOWLEDGMENTS

Landscape ecology has rapidly emerged in the past decade to become usable and important to practicing land-use planners and landscape architects. The focus on heterogeneous land mosaics, such as neighborhoods, whole landscapes, and regions, is at increasingly the critical spatial scale. Animals, plants, water, materials, and energy are spatially distributed, move, flow, and change in predictable ways in these mosaics. Thus professionals and scholars have incorporated bits of the new field in their work. But many have also requested a summary of key principles, and how they might be applied in design and planning.

This publication is therefore a handbook or primer, listing and illustrating many key principles. It also provides examples of how the principles can be applied in design, planning, and solving vexing land-use issues.

The book is not a cookbook giving exact ingredients and steps. Designers and planners are rife with creativity and original ideas. The principles presented are solid background colors on the professional’s palette, the foundations that are combined to produce important new designs and solutions.

If society decides, for example, to add a road, a nature reserve, or a housing tract, these principles will help accomplish the goal by maximizing ecological integrity, and minimizing land degradation. Furthermore, principles at this relatively broad scale become a surrogate for long time. They nudge society into long-term planning and decision-making.

Using the principles is not difficult, and leads to more integrative designs and plans. It helps reduce the landscape fragmentation and degradation so evident around us. Individual professionals familiar with landscape ecology already accomplish these specific results.

In addition though, solutions to environmental and societal problems require cross-disciplinary design and planning by groups. Another objective of this book is to strengthen the two-way street between ecologists and planners/landscape architects. Plenty of ecologists will also read this book, and some will take a deeper interest in landscape architecture and land-use planning. Such a synergism will result in deeper understanding of the landscape ecology principles, the development of additional useful principles, and their better application in land planning and design.

Present Addresses:

¹ Agricultural University of Norway Department of Biology and Nature Conservation

P.O. Box 5014

N-1432 As, Norway

²4 Tamworth Road

Waban, MA 02168

We are pleased to acknowledge the key financial support of the following organizations that made this book possible:

Agricultural University of Norway

Harvard University Graduate School of Design

The Research Council of Norway

Sasaki Associates, Inc.

We also deeply appreciate and are delighted to acknowledge the following persons: J. Thomas Atkins (Jones & Jones, Seattle, Washington), Margot D. Cantwell (Environmental Design and Management, Halifax, Canada), Leslie Kerr (U. S. Fish and Wildlife Service, Anchorage, Alaska), Alistair T. McIntosh (Sasaki Associates, Watertown, Massachusetts), and Mary Ann Thompson (Thompson and Rose Architects, Cambridge, Massachusetts) provided important critical reviews from the perspective of practicing professionals. Carl Steinitz (Harvard University) kindly permitted us to test an earlier draft in his class studio. Tricia Bales, Jorgen Blomberg,