Table Of ContentALB
Advances in Life Sciences
Tropical Forests
in Transition
Ecology of Natural and Anthropogenic
Disturbance Processes
Edited by
J.G. Goldammer
Birkhauser Verlag
Basel' Boston' Berlin
Editor's address:
Dr. Johann Georg Goldammer
Max Planck Institute of Chemistry
Biogeochemistry Department (Mainz)
Fire Ecology and Biomass Burning Research Group
clo University of Freiburg
Bertoldstr. 17
D-7800 Freiburg
Germany
Deutsche Bibliothek Cataloging-in-Publication Data
Tropical forests in transition: ecology of natural and anthropogenic disturbance processes
I ed. by J. G. Goldammer. - Basel; Boston; Berlin: Birkhauser, 1992
(Advances in life sciences)
ISBN-13: 978-3-0348-7258-4 e-ISBN-13: 978-3-0348-7256-0
DOl: 10.1007/978-3-0348-7256-0
NE: Goldammer, Johann Georg [Hrsg.]
This work is subject to copyright. All rights are reserved, whether the whole or part of the
material is concerned, specifically those of translation, reprinting, re-use of illustrations,
broadcasting, reproduction by photocopying machine or Similar means, and storage in data
banks. Under § 54 of the German Copyright Law, where copies are made for other than private
use a fee is payable to «Verwertungsgesellschaft Wort», Munich.
© 1992 Birkhauser Verlag
Softcover reprint of the hardcover 1s t edition 1992
P.O. Box 133
4010 Basel
Switzerland
ISBN-13: 978-3-0348-7258-4
v
Contents
Preface VII
Tropical Forests in Transition: Ecology of Natural and
Anthropogenic Disturbance Processes - An Introduction
J.G.Goldammer
Palynological Evidence Relating to Disturbance
and Other Ecological Phenomena of Rain Forests
J.R.Flenley 17
Holocene Autochthonous Forest Degradation in Southeast Venezuela
H.Folster 25
Vegetation, Megaherbivores, Man and Climate in the Quaternary
and the Genesis of Closed Rain Forests
W.SchQle 45
Succession After Disturbance of Lowland Mixed Dipterocarp Forest
by Shifting Agriculture in East Kalimantan, Indonesia
S. Riswan and R. Abdulhadi 77
Degradation of a Forest in the Shimba Hills National Reserve,
Kenya, as Initiated by Man and Maintained by Wildlife
R.Schmidt 85
Anthropo-Zoogenic Impact on the Structure and Regeneration
of a Submontane Forest in Kenya
K. Schmitt 105
Tropical Mountain Ecology in Ethiopia as a Basis of Conservation,
Management and Restoration
S.K.Uhlig 127
Forests for Integrated Land-Use Development in an Eastern
Ethiopian Water Catchment
H.Uibrig 135
Geoecological Consequences of Human Impacts on Forests
in Sri Lanka
C.Preu and W.Erdelen 147
Structure and Dynamics of the Upper Montane Rain Forests
of Sri Lanka
W.L.Werner and S. Balasubramaniam 165
A Research Perspective on Disturbance and Recovery
of a Tropical Montane Forest
R.B.Waide and A.E.Lugo 173
VI
Process-Oriented Models for Simulation of Growth Dynamics
of Tropical Natural and Plantation Forests
H.Schater, H.Krieger and H.Bossel 191
A Finite-Element Model to Simulate Spacial Distributions
of Populations of Large Mammals
A.SchOle 225
The Role of the Tropics in the Global Carbon Budget:
Impacts and Possible Developments
G.Esser 241
Modeling the Response of Terrestrial Vegetation
to Climate Change in the Tropics
T.M.Smith, J.B.Smith Jr. and H.H.Shugart 253
Subject Index 269
VII
Preface
In evolutionary time scales natural disturbances have affected the vegetation on
Earth. During the Quaternary the forest biomes of the tropics were subjected to
manifold disturbances. Climate changes and climate oscillations were associated
with changing precipitation and drought regimes, flooding, siltation, landslides, etc.
The prehistorical forest was also influenced by the effects of large wildlife
populations. Large-scale catastrophies in the forest biomes were mainly caused by
abiotic environmental alterations, the small-scale disturbances were and still are
related to both biotic and abiotic processes. Both the large- and the small-scale
disturbances have played a significant role in shaping distribution, dynamics,
structure and composition of the paleoforest.
After the expansion of hominids and early humans, and later, by modern humans,
the anthropogenic influences on the tropical forest began to overlap natural
disturbances. Today's anthropogenic impacts on the tropical forests differ
qualitatively and quanitatively from the natural disturbances. The speed of tropical
deforestation and savannization is dramatically increasing. The physical and
chemical impacts of forest conversion and biomass burning add to other
anthropogenic influences on the atmosphere and climate. The expected
anthropogenic climate change will also have considerable impacts on the tropical
flora and fauna.
The book on "Tropical Forests in Transition" synthesizes information on changing
environmental conditions and human impacts on the tropical forest by looking back
to the paleoecology, analyzing the impact of modern human populations and
modeling the future of the tropical forest in a changing environment. The aim of
the book is to strengthen multidisciplinary thinking in disturbance ecology.
Acknowledgements
The contributors to this book convened at the University of Freiburg (Germany)
under the sponsorship of the German Society of Tropical Ecology and the Fire
Ecology and Biomass Burning Research Group". Financial support was provided by
the Deutsche Forschungsgemeinschaft (DFG) and the Ministry of Science and Arts
of the State of Baden-Wurttemberg. Valuable assistance was given by the
University of Freiburg, particularly by the Institute of Forest Zoology, the Institute
of Biology I and the Faculty of Forest Sciences. The editor is indebted to Doris
Spitzer, for preparing the camera-ready manuscript of the book, and to Jennifer
Johns, for a final critical linguistic review of the contributions.
Freiburg (Germany). January 1992 Johann Georg Goldammer
• The Fire Ecology and Biomass Burning Research Group is a Subdivision of the Max Planck Institute
of Chemistry, Biogeochemistry Department (Mainz, Germany), and is located at the University of
Freiburg, Institute of Forest Zoology
Tropical Forests in 1tansition 1
I. G. Goldammer (ed.)
© 1992 Birkhiiuser Verlag Basel/Switzerland
Tropical Forests in Transition. Ecology of Natural and Anthropogenic
Disturbance Processes - An Introduction
Johann Georg Goldammer
Abstract
Recent paleoecological, biogeographical, atmospheric and climatological findings have
revealed that general conceptions of the assumed ageless stability of today's tropical
forest ecosystems can no longer be supported. Pleistocene climatic changes and
Holocene climate oscillations have caused significant fluctuations in tropical forest
biomes, which leads to the conclusion that patterns of distribution and species
composition of today's tropical forest formations are closely related to the relatively
short period of modern climate conditions.
In addition to the impact of climate change, other forces such as anthropogenic forest
disturbance, the ecological feedback mechanisms of deforestation and other human
induced environmental changes, determine the present and the possible future
development of the tropical forest biota. A predictive assessment of tropical forest
development requires detailed knowledge of interacting ecological processes, that is, the
coupling of small-scale impacts (e.g. timber extraction, shifting cultivation, grazing, fire)
with large-scale feedback mechanisms (e.g. atmospheric changes, meso- and macro
climate change).
A thorough understanding of paleoclimate and forest changes and the coupling of
terrestrial ecology with atmospheric sciences will be imperative to predict the possible
development of tropical forests in transition to a new climate-supported equilibrium. The
introductory paper to this volume gives some selected examples of past and present
natural disturbance processes in the tropical forest biota. The possible impacts of
anthropogenic disturbances on present and future ecosystem processes are highlighted.
'Fire Ecology and Biomass Burning Research Group of the Max Planck Institute of Chemistry, Biogeochemistry
Department (Mainz, Germany), at the Department of Forestry, University of Freiburg, Bertoldstr. 17, 0-7800
Freiburg, Germany
2 J.G. Goldammer
Introduction
During the past decade the growing threat to the world's tropical forests by the impact
of human civilization has received increasing attention on public and political levels. The
demand for a reliable scientific base and for information on the state of the global
tropical forest reserves and on the ecological impacts of the utilization, the degradation
and the destruction of the tropical forest has been increased accordingly. The warning
signals directed to the public by an increasing number of tropical forest ecologists
cannot be overheard - and the relevant publications and political statements are
becoming countless.
It is not the intent of this paper and of this volume to add to the various attempts to
explain and to quantify the destruction or conversion rate of the world's tropical forests;
the interested reader is refered to synoptic summaries such as the state-of-knowledge
report on the protection of tropical forest resources by the German Parliament
(Deutscher Bundestag 1990).
The aim of this volume is rather to highlight and to elaborate on a multidisciplinary
interpretation of the disturbance (or "interference") ecology of the tropical forests (1)
along a broad time scale, ranging from the Pleistocene to the 2xC0 climate, (2) by
2
developing an objective approach that would explain the functional role of disturbances,
and (3) by relating the impacts of anthropogenic disturbances to natural disturbances by
avoiding subjective valuation of contemporary forest destruction. This approach was
based on following considerations:
It is generally accepted that during evolutionary time scales tropical forests were
subjected to manifold disturbances related to abiotic and biotic stresses. This
especially refers to the Pleistocene climate changes during which the tropical
forest underwent dramatic reduction in distribution and changes in species
composition. An overall comparison of the suggested distribution of the tropical
forest area during the last glaciations with the extent of today's forest cover
reveals that at present the tropical rain forests occupy a considerably larger area
(cf. syntheses by Flenley [1979] and Prance [1982]).
It is widely recognized that small- to large-scale disturbances, e.g. in the
equatorial rain forest, are key processes in the diversification (speciation) and
specialization of species, thus being responsible for the richness of species in the
tropical forest biota. From a phylogenetic point of view, these disturbances must
have played a role that could be explained as a functional task in evolution (cf.
syntheses by Pickett & White [1985] and Platt & Strong [1989]).
The regular influence of natural and anthropogenic disturbances, such as fire,
have created unique seral forest ecosystems that may be valued - from a socio
ecological point of view -to be highly sustainable and productive (cf. Goldammer
[1990]).
While it is evident that natural climate changes or climate oscillations playa key role in
the development and changes of forests, it becomes increasingly clear that supra
regional or even global interference processes other than climate patterns also have
considerable impacts on forest ecosystems. One of the most striking examples is the
