PLANT LITTER : decomposition, humus formation, carbon sequestration.

342 Pages·2020·7.686 MB·English

by  BJRN BERG

Björn Berg
Charles McClaugherty
Plant Litter
Decomposition, Humus Formation,
Carbon Sequestration
Fourth Edition
Plant Litter
ö
Bj rn Berg Charles McClaugherty
(cid:129)
Plant Litter
Decomposition, Humus Formation, Carbon
Sequestration
Fourth Edition
123
Björn Berg CharlesMcClaugherty
Departments ofForest Sciences Department ofBiology
University of Helsinki University of Mount Union
Helsinki, Finland Alliance, OH, USA
ISBN978-3-030-59630-9 ISBN978-3-030-59631-6 (eBook)
https://doi.org/10.1007/978-3-030-59631-6
1st,2ndand3rdeditions:©Springer-VerlagBerlinHeidelberg2003,2008,2014
4thedition:©SpringerNatureSwitzerlandAG2020
Thisworkissubjecttocopyright.AllrightsarereservedbythePublisher,whetherthewholeorpart
of the material is concerned, specifically the rights of translation, reprinting, reuse of illustrations,
recitation, broadcasting, reproduction on microfilms or in any other physical way, and transmission
orinformationstorageandretrieval,electronicadaptation,computersoftware,orbysimilarordissimilar
methodologynowknownorhereafterdeveloped.
The use of general descriptive names, registered names, trademarks, service marks, etc. in this
publicationdoesnotimply,evenintheabsenceofaspecificstatement,thatsuchnamesareexemptfrom
therelevantprotectivelawsandregulationsandthereforefreeforgeneraluse.
The publisher, the authors and the editors are safe to assume that the advice and information in this
book are believed to be true and accurate at the date of publication. Neither the publisher nor the
authors or the editors give a warranty, expressed or implied, with respect to the material contained
hereinorforanyerrorsoromissionsthatmayhavebeenmade.Thepublisherremainsneutralwithregard
tojurisdictionalclaimsinpublishedmapsandinstitutionalaffiliations.
ThisSpringerimprintispublishedbytheregisteredcompanySpringerNatureSwitzerlandAG
Theregisteredcompanyaddressis:Gewerbestrasse11,6330Cham,Switzerland
Preface
When starting our work on this book, now about 20 years ago, we intended to
summarizeandsynthesizethenewinformationthathaddevelopedinthelast20–30
yearsinthefieldofplantlitterdecomposition.Itturnedout,however,thatthemain
part of recent work both 20 years ago and today has been directed toward boreal
and temperate forest systems, and therefore, with a focus on these ecosystems, we
finallyconcludedasynthesisthathasasimilaritytoacasestudy.Still,wehopethat
a deeper insight into the behavior of a limited number of litter species will be of
value for a generalization and also for the identification of process systems that
deviate from those presented here.
We have written the book focusing on the transfer from newly shed litter to
recalcitrant humus, describing and explaining the system of chemical changes
taking place in the process both on a mechanistic basis and on a more general and
regional level, considering different climates and species.
Asasynthesis,thisbookgivessomenewperspectivesondecompositionthatto
some may seem controversial. Thus, the fact that we emphasize the dominant role
ofmicroorganismsintheprocessmaybedisturbingtomanyreaders,aswellasthe
strong emphasis we give to the fact that humus layers actually do grow over
millennia and that at a considerable rate, and thus really sequester, e.g., C and N.
This book is based primarily on data and conclusions made from field studies.
We have focused on undisturbed forest systems in an attempt to create a basic
understanding and describe basic mechanisms for the decomposition and trans-
formation processes. Its emphasis is on boreal systems for the obvious reason that
there appeared to exist more data about these systems that could be synthesized.
The information from temperate systems has rather supported and extended the
conclusions, suggesting that the synthesis so far may be applicable to at least both
types of systems.
In the topic of litter decomposition and transformations, we cannot yet identify
different schools of thought; it appears that this field of research has not yet
developedfarenough.Wewouldratherconsiderdifferentdirectionsoftheresearch
work. Thus, some scientists have attempted to understand mechanisms for the
degradation, whereas several groups have searched for indices for prediction of
v
vi Preface
long-term decomposition rates. We have seen in recent years, however, a strong
development in the field of root decomposition and in new analytical methods
(13C-NMR).
Thefirstsynthesisthatwepresentedin2003hadclearlytakenimpressionofthe
workbyasmallergroupofscientistsandresearchgroupsthatwewanttogratefully
acknowledge. Thus, the papers emerging from the group around Dr. Marie-
MadeleineCouteaux,CNRS,Montpellier,havebeenimportanttous,ashavethose
from Prof. John Aber, University of New Hampshire, and Dr. Jerry Melillo, The
Ecosystems Center, MBL, Woods Hole.
Many other persons have been helpful in the process of collecting and devel-
oping the information that makes up the backbone for this book and its develop-
ment. We want to thank all of them and hope they understand that all cannot be
listed here.
New and valuable data have appeared from the large US project Long-Term
Intersite Decomposition Experiment Team (LIDET) and from the Canadian
Intersite Decomposition Experiment (CIDET). The new analytical methods using
13C-NMR for determiningorganic compounds indecomposing litter, developed in
Canada,Italy,andJapan,haveprovideduswithnewinsightsandmaychangeolder
theoriesabouttheprocessoflitterdecomposition.Forthefourthedition,alargeset
ofdataondecompositionofrootshasbeenpublished,whichalsohasinfluencedthe
structure of this book.
For the first edition, the support of the Brumbaugh Center for Environmental
Science, University of Mount Union, Alliance, Ohio, is also gratefully acknowl-
edged.GoodandsubstantialfinancialsupportfromtheBITÖKinstitute,University
of Bayreuth, Germany, and from the Commission of the European Union, through
the CNTER project (QLK5-2001-00596), is acknowledged.
Forthesecond,third,andfourtheditions,wehaveusedmuchofthedataandthe
views on regionalization to different climates that have been developed by Prof.
Vernon Meentemeyer, University of Georgia, Athens. These have been extremely
valuable. Likewise, the recent papers of Dr. Chunjiang Liu, School of Agriculture
and Biology, Shanghai Jiao Tong University and Key Laboratory of Urban
Agriculture (South), Ministry of Agriculture, Shanghai, have contributed to the
synthesis.Therecentworkonfineroots/roottipsbyDr.TaoSun,KeyLaboratoryof
Forest Ecology and Management, Institute of Applied Ecology, Chinese Academy
of Sciences,Shenyang,has given avery valuableinput to thefourth edition.
We have been allowed to use unpublished data and express our thanks to Drs.
Cecilia Akselsson, Maj-Britt Johansson, Anna Hagen-Thorn, Per Gundersen, and
Åke Nilsson. We also want to thank Prof. Egbert Matzner, BITÖK, University of
Bayreuth,Prof.Carl-JohanWestman,DepartmentofForestEcology,Universityof
Helsinki, and Prof. Amalia Virzo De Santo, Dipartimento Biologia Strutturale e
Funzionale, University of Naples Federico II, for their extensive support for this
book.
Preface vii
Now that the fourth edition has been finished we want to express our appreci-
ation of the valuable help and support we have received. Finally, before handing
over the book to the reader, we would like once again to thank each other for an
excellent cooperation.
Uppsala, Sweden/Helsinki, Finland
July 2020
Björn Berg
Alliance, USA
July 2020
Charles McClaugherty
Contents
1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.1 Overview of Plant Litter Decomposition. . . . . . . . . . . . . . . . . . 1
1.2 A Short Retrospective. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
1.3 The Ecological Significance of Litter Decomposition
and the Formation of Humus. . . . . . . . . . . . . . . . . . . . . . . . . . 3
1.4 Factors Influencing Decay and Humus Formation. . . . . . . . . . . 5
1.5 Accumulation of Humus and Nutrients. . . . . . . . . . . . . . . . . . . 5
1.6 The Contents and Organization of the Book. . . . . . . . . . . . . . . 7
1.7 Motives for the Present Synthesis . . . . . . . . . . . . . . . . . . . . . . 9
1.8 New Developments Included in the Fourth Edition. . . . . . . . . . 10
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
2 Decomposition as a Process—some Main Features . . . . . . . . . . . . . 13
2.1 Litter Decomposition—a Set of Different Processes Including
Synthesis of New Compounds. . . . . . . . . . . . . . . . . . . . . . . . . 13
2.2 Definition of Litter Decomposition. . . . . . . . . . . . . . . . . . . . . . 17
2.3 Ash Dynamics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
2.4 Nutrients Limiting for Litter Decomposition—some
Observations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
2.5 Degradation of the Main Groups of Organic Compounds
in Foliar Litter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
2.5.1 Degradation and Leaching of Soluble Organic
Substances. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
2.5.2 Degradation of Non-Lignified Organic Substances . . . . 23
2.5.3 A Pattern of Degradation of the Main Organic
Compounds in Pine Needle Litter . . . . . . . . . . . . . . . . 24
2.5.4 Some Chemical Changes during Decomposition
thatMayBeincommonforFoliarLitteroverSpecies
and Genera . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
ix
x Contents
2.5.5 Pattern for Main Organic Compounds Based
on AUR—Gravimetric Analyses of Lignin. . . . . . . . . . 26
2.5.6 13C-NMR Analysis Applied to Decomposing Foliar
Litter. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
2.6 Factors Regulating Degradation of Lignin/AUR . . . . . . . . . . . . 30
2.6.1 Potential Effects and Possible Interactions
on Lignin/AUR Degradation. . . . . . . . . . . . . . . . . . . . 30
2.6.2 Effects of Litter Mn Concentration on Lignin/AUR
Degradation and Litter Mass Loss. . . . . . . . . . . . . . . . 30
2.6.3 Effects of N on Lignin/AUR and Late-Stage Litter
Degradation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
2.7 Proposed Models for Decomposition from Newly Shed Foliar
Litter to the Humus Stage . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
2.7.1 Three-Stage Model. . . . . . . . . . . . . . . . . . . . . . . . . . . 35
2.7.2 The Two-Stage Model . . . . . . . . . . . . . . . . . . . . . . . . 36
2.7.3 In common for both Models—the Humus-Near
or Limit-Value Stage . . . . . . . . . . . . . . . . . . . . . . . . . 37
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
3 Decomposer Organisms. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
3.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
3.2 General Properties of a Given Microbial Population . . . . . . . . . 47
3.3 The Degradation of the Main Polymers in Litter. . . . . . . . . . . . 48
3.3.1 Degradation of Cellulose . . . . . . . . . . . . . . . . . . . . . . 48
3.3.2 Degradation of Hemicelluloses . . . . . . . . . . . . . . . . . . 51
3.3.3 Degradation of Lignin . . . . . . . . . . . . . . . . . . . . . . . . 52
3.4 Degradation of Fibers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
3.4.1 Bacteria. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
3.4.2 Soft-Rot. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
3.4.3 Brown-Rot. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
3.4.4 White-Rot . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
3.5 Mycorrhizae . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
3.6 Ecological Aspects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63
4 Initial Litter Chemical Composition . . . . . . . . . . . . . . . . . . . . . . . . 67
4.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67
4.2 Organic Chemical Components of Plant Litter and Fiber
Structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69
4.2.1 Organic Chemical Components . . . . . . . . . . . . . . . . . . 69
4.2.2 Fiber Structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74
4.3 Nutrient and Heavy Metal Concentrations in Newly Shed
Litter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76
4.3.1 General Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76
4.3.2 Nutrient Resorption and Withdrawal Efficiency . . . . . . 77
Contents xi
4.3.3 NutrientConcentrationChange;GreenFoliageversus
Brown Litter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79
4.4 Factors Influencing Litter Chemical Composition . . . . . . . . . . . 81
4.4.1 General Factors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81
4.4.2 Nutrients, Heavy Metals, and AUR in Needle Litter
of two Conifers, Pine, and Spruce Spp—two Case
Studies in Climate Gradients. . . . . . . . . . . . . . . . . . . . 83
4.4.3 Influence of Soil Properties. . . . . . . . . . . . . . . . . . . . . 88
4.4.4 Influence of Tree Age. . . . . . . . . . . . . . . . . . . . . . . . . 89
4.5 Several Deciduous and Coniferous Leaf Litter Species . . . . . . . 90
4.5.1 Variation in a Eurasian—Global Gradient—Focus
on Nitrogen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90
4.5.2 Coniferous versus Deciduous Genera/Species
and Influence of Species—an Old Concept . . . . . . . . . 92
4.5.3 General and Global Relationships . . . . . . . . . . . . . . . . 93
4.6 Wood, Cones, and Fine-Root Litter . . . . . . . . . . . . . . . . . . . . . 94
4.7 Anthropogenic Influences on Initial Litter Composition. . . . . . . 95
4.7.1 N-Fertilized Scots Pine and Norway Spruce
Monocultures. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97
5 Changes in Substrate Composition During Decomposition . . . . . . . 101
5.1 Introductory Comments. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101
5.2 Organic Chemical Changes during Litter Decomposition. . . . . . 103
5.2.1 Traditional Analytical Fractions. . . . . . . . . . . . . . . . . . 103
5.2.2 Relationships between Holocellulose and AUR . . . . . . 107
5.2.3 13C–NMR Technique . . . . . . . . . . . . . . . . . . . . . . . . . 108
5.3 The Dynamics of Mn, Ca, K, and N . . . . . . . . . . . . . . . . . . . . 110
5.3.1 Manganese Dynamics. . . . . . . . . . . . . . . . . . . . . . . . . 111
5.3.2 Calcium Dynamics. . . . . . . . . . . . . . . . . . . . . . . . . . . 114
5.3.3 Potassium Dynamics. . . . . . . . . . . . . . . . . . . . . . . . . . 117
5.3.4 Nitrogen Concentration Dynamics over a Climatic
Gradient. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120
5.4 A Special Study on Minor Elements/Heavy Metals—Early
to Late-Stage Decomposition. . . . . . . . . . . . . . . . . . . . . . . . . . 124
5.4.1 Concentration Dynamics. . . . . . . . . . . . . . . . . . . . . . . 124
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 126
6 Role of Chemical Constituents in Regulating Decay Rates
and Stable Fractions: Effects of Initial and Changing Chemical
Composition on Decomposition and Organic Matter
Accumulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 129
6.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 129
6.2 Some Nutrients and Compounds in Litter Influencing
Decomposition Rates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 131