This page intentionally left blank Primary Succession and Ecosystem Rehabilitation Natural disturbances such as lava flows, landslides and glacial moraines, and human-damaged sites such as pavements, road edges and mine wastes, often leave little or no soil or biological legacy. This book provides the first com- prehensive summary of how plant, animal and microbial communities develop under the harsh conditions following such dramatic disturbances. The authors examine the basic principles that determine ecosystem development and apply the general rules to the urgent practical need for promoting the reclamation of damaged lands. Written for those concerned with disturbance, landscape dynamics, restoration, life histories, invasions, modeling, soil formation and community or population dynamics, this book will also serve as an authorit- ative text for graduate students and a valuable reference for professionals in- volved in land management. Lawrence R. Walker is Professor of Biological Sciences at the University of Nevada, Las Vegas. His resear ch focuses on the mechanisms that drive primary succession and the applications of succession to restoration. Roger del Moral is Professor of Botany at the University of Washington. His research relates observed patterns of vegetation recovery to ecological theory. Primary Succession and Ecosystem Rehabilitation LAWRENCE R. WALKER University of Nevada, Las Vegas and ROGER DEL MORAL University of Washington, Seattle Cambridge, New York, Melbourne, Madrid, Cape Town, Singapore, São Paulo Cambridge University Press The Edinburgh Building, Cambridge , United Kingdom First published in print format isbn-13 978-0-521-80076-1 hardback isbn-13 978-0-521-52954-9 p a p erback isbn-13 978-0-511-06328-2 eBook (NetLibrary) © Lawrence R. Walker and Roger del Moral 2003 2003 Information on this title: www.cambrid g e.or g /9780521800761 This book is in copyright. Subject to statutory exception and to the provision of relevant collective licensing agreements, no reproduction of any part may take place without the written permission of Cambridge University Press. isbn-10 0-511-06328-8 eBook (NetLibrary) isbn-10 0-521-80076-5 hardback isbn-10 0-521-52954-9 p a p erback Cambridge University Press has no responsibility for the persistence or accuracy of s for external or third-party internet websites referred to in this book, and does not guarantee that any content on such websites is, or will remain, accurate or appropriate. Published in the United States of America by Cambridge University Press, New York www.cambridge.org - - - - - - Contents Prefaceandacknowledgementspagexi 1Introduction1 1.1Whylearnaboutprimarysuccession?1 1.1.1Humansanddisturbance2 1.1.2Humaninterestinecosystemrecovery5 1.2Definitions5 1.3Methods9 1.4Questionsthatstillremain12 2Denudation:thecreationofabarrensubstrate14 2.1Concepts14 2.1.1Physicalenvironmentanddisturbance14 2.1.2Definitions15 2.1.3Plantsandanimalsasagentsofdisturbance17 2.1.4Patchdynamics17 2.2Typesofdisturbancethatinitiateprimarysuccession19 2.2.1Earth19 2.2.2Air33 2.2.3Water36 2.2.4Fire41 2.2.5Humans42 2.2.6Disturbanceinteractions48 2.2.7Summaryofdisturbancetypes50 3Successionaltheory52 3.1Introduction52 3.2Earlyobservations54 3.3Holism55 3.4Neo-holism60 3.5Phytosociology62 vi · Contents 3.6Reductionism63 3.7Neo-reductionism65 3.8Ecosystemassembly68 3.9Models70 3.9.1Verbalmodels72 3.9.2Mathematicalmodels83 3.10Newdirections86 4Soildevelopment88 4.1Background88 4.2Environmentalcontrols89 4.2.1Climate90 4.2.2Parentmaterial91 4.2.3Topography92 4.2.4Erosion93 4.3Physicalandchemicalproperties95 4.3.1Texture95 4.3.2Compaction98 4.3.3Watercontent100 4.3.4pHandcations102 4.3.5Nitrogen105 4.3.6Phosphorus108 4.4Soilbiota112 4.4.1Plants112 4.4.2Soilmicrobes113 4.4.3Mycorrhizae115 4.4.4Animals117 4.5Soilprocesses118 4.5.1Nitrogenfixation118 4.5.2Organicmatter123 4.6Spatialpatterns127 4.7Summary129 5Lifehistoriesofearlycolonists133 5.1Introduction133 5.2Pre-dispersalconsiderations133 5.2.1Pollinationandseedset134 5.2.2Seedbanks136 5.2.3Vegetativereproduction139 Contents · vii 5.3Dispersal141 5.3.1Dispersalparameters142 5.3.2Dispersalmechanismsandtheirconsequences145 5.3.3Barriers156 5.3.4Predictability160 5.3.5Dispersalconclusions163 5.4Establishment164 5.4.1Germination164 5.4.2Growth170 5.5Persistenceandlongevity177 5.5.1Persistence177 5.5.2Longevity179 5.6 Successional consequences of dispersal andestablishment181 5.6.1 Under-saturated early successional communities181 5.6.2 Under-saturated late successional communities181 5.6.3Novelspeciesassemblages183 5.6.4Priorityeffects184 5.6.5Disharmoniccommunities184 5.6.6Biogeographicaleffects186 5.6.7Establishmentconclusions187 6Speciesinteractions189 6.1Introduction189 6.2Plant–soilandanimal–soilinteractions191 6.2.1Plantimpactsonsoils191 6.2.2Animaldisturbances198 6.3Interactionsamongplants198 6.3.1Facilitation199 6.3.2Inhibition209 6.4Interactionsbetweenplantsandotherorganisms217 6.4.1Mutualisms217 6.4.2Herbivores218 6.4.3Parasitism223 6.5Interactionsbetweenanimals224 6.6Neteffectsofinteractions226 viii · Contents 7Successionalpatterns232 7.1Typesoftrajectory232 7.1.1Convergingtrajectories235 7.1.2Divergingtrajectories240 7.1.3Trajectorynetworks243 7.1.4Paralleltrajectories245 7.1.5Deflectedtrajectories246 7.1.6Cyclicpatternsandfluctuations249 7.1.7Retrogressivetrajectories249 7.1.8Arrestedtrajectories250 7.1.9Trajectorysummary251 7.2Temporaldynamics252 7.2.1Definitions253 7.2.2Methodsofmeasuringrates254 7.3Changesinbiodiversityandbiomass258 7.3.1Biodiversity258 7.3.2Stability259 7.3.3Biomassandallocation259 7.4Environmentalfeedback261 7.4.1Moisture262 7.4.2Temperature264 7.4.3Nutrients266 7.4.4Salinity270 7.4.5Landscapefactors273 7.4.6Chronicdisturbance273 7.4.7Pollution275 7.5Summary276 8Applicationsoftheoryforrehabilitation282 8.1Theoryofrehabilitationecology282 8.1.1Introductionanddefinitions282 8.1.2 Interdependency between rehabilitation andecologicaltheory284 8.2Rehabilitationprocesses287 8.2.1Conceptualframework287 8.2.2Planning292 8.3Implementation295 8.3.1Dispersal296 8.3.2Establishment297 [...]... context and site history All new surfaces are initially devoid of life, so primary succession has been crucial throughout Earth’s history Today, all communities of plants, animals and soils are the result of primary succession It is this process of recovery of ecosystems after disturbance that provides the clean air and water and fertile soils that humans and all organisms need to survive Ecosystem. .. directs and may stop or redirect succession (see Chapters 2 and 7), so an understanding of its complexities is critical to interpreting successional pathways Disturbance and succession are both broad terms, difficult to define precisely, yet unavoidably crucial when interpreting temporal change Disturbance and succession are also strongly interactive, although Grubb (1988) points out that succession and. .. our ability to understand primary succession The exponential increase in human numbers and declining resource availability lend great urgency to the search for more efficient resource use and habitat rehabilitation We hope that this book will provide a comprehensive 2 · 1 Introduction understanding of the mechanisms of primary succession that will facilitate that search 1.1.1 Humans and disturbance Humans... of primary succession is due mostly to allogenic 1.3 Methods · 9 mechanisms, but internal, autogenic mechanisms become more important as succession proceeds (Matthews, 1992) However, as with most dichotomies (cf primary and secondary succession) , autogenic and allogenic succession represent endpoints of a continuum Any given sere is the consequence of a mixture of both mechanisms and it is unwise and. .. Euphrates and Nile to sustain soil fertility and civilization Away from floodplains, farmers have had to manipulate succession to produce crops on infertile sites Present-day ecologists use lessons from primary succession in many ways (e.g to create new habitats and to rehabilitate mined lands and pastures) Effective manipulations of our environment to improve fertility, productivity or diversity and an... damaged terrestrial and aquatic systems is just as essential as recycling of waste products into useful resources We maintain that the best approach to rehabilitation is the merger of science and management This book aims to forge links between successional theory and potential applications of that knowledge Communication between scientists and land managers, theorists and practitioners of rehabilitation. .. professional scientists and students of ecology looking for synthesis of ideas from research on succession, competition, facilitation, ecosystem assembly, conservation and rehabilitation This book will easily xii · Preface and acknowledgements serve as a textbook and summary of a complex yet interrelated collection of ideas We also hope that land managers from government, corporate and non-profit organizations... curiosity and scientific methodology Now we summarize what we have learned and what we believe still needs study Our second reason for writing this book was because we feel the urgency of understanding the natural and human-assisted processes involved in ecosystem rehabilitation With the spiraling challenges of overpopulation and resource depletion, including a startling loss in arable land, rehabilitation. .. theory of succession, even if there will never be a ‘grand underlying scheme’ (GUS) that explains all successional change We address such theoretical issues about succession in Chapter 3 Can studies of primary succession lead to practical generalizations about rehabilitation? Environmental regulations increasingly require polluters and excavators to restore severely damaged habitats such as mined lands... which primary succession begins The type (texture) and shape (slope) of each surface can impact such variables as site moisture and fertility by their effects on substrate stability and accumulation of water, litter, plants, animals and decomposers (Fig 2.1) (Turner et al., 1997) Clements (1928) noted that the balance of the opposing forces of erosion and sedimentation, subsidence and uplift, flooding and . left blank Primary Succession and Ecosystem Rehabilitation Natural disturbances such as lava flows, landslides and glacial moraines, and human-damaged sites such as pavements, road edges and mine. of vegetation recovery to ecological theory. Primary Succession and Ecosystem Rehabilitation LAWRENCE R. WALKER University of Nevada, Las Vegas and ROGER DEL MORAL University of Washington,. Contents 7Successionalpatterns232 7.1Typesoftrajectory232 7.1.1Convergingtrajectories235 7.1.2Divergingtrajectories240 7.1.3Trajectorynetworks243 7.1.4Paralleltrajectories245 7.1.5Deflectedtrajectories246 7.1.6Cyclicpatternsandfluctuations249 7.1.7Retrogressivetrajectories249 7.1.8Arrestedtrajectories250 7.1.9Trajectorysummary251 7.2Temporaldynamics252 7.2.1Definitions253 7.2.2Methodsofmeasuringrates254 7.3Changesinbiodiversityandbiomass258 7.3.1Biodiversity258 7.3.2Stability259 7.3.3Biomassandallocation259 7.4Environmentalfeedback261 7.4.1Moisture262 7.4.2Temperature264 7.4.3Nutrients266 7.4.4Salinity270 7.4.5Landscapefactors273 7.4.6Chronicdisturbance273 7.4.7Pollution275 7.5Summary276 8Applicationsoftheoryforrehabilitation282 8.1Theoryofrehabilitationecology282 8.1.1Introductionanddefinitions282 8.1.2 Interdependency between rehabilitation andecologicaltheory284 8.2Rehabilitationprocesses287 8.2.1Conceptualframework287 8.2.2Planning292 8.3Implementation295 8.3.1Dispersal296 8.3.2Establishment297 Contents·ix 8.3.3Monitoring300 8.3.4Maintenance301 8.4Overcomingadverseconditions301 8.4.1Drought302 8.4.2Hydricconditions303 8.4.3Infertilityandtoxicity306 8.4.4Salinity311 8.4.5ExtremepHvalues312 8.4.6Lowtemperatures313 8.4.7Unstablesubstrates314 8.4.8Alienplants315 8.4.9Grazing317 8.4.10Airpollution318 8.4.11Overcomingadversity:asummary319 8.5Feedbackbetweentheoryandpractice322 8.5.1Increasingrestorationrates322 8.5.2Improvingtheaim323 8.5.3Enlargingthetarget325 8.5.4