MINISTERE DES AFFAIRES CULTURELLES TRA VAUX SCIENTIFIQUES DU MUSEE NATIONAL D'HISTOIRE NATURELLE DE LUXEMBOURG 21 Ecology and Vegetation of Mt Trikora New Guinea (lrian Jaya I Indonesia) by Jean-Marie MANGEN Luxenibourg, 1993 Cover: The north face of Mt Trikora (4725 m): looki ng south from Somalak valley, altitude 3800 m Musee national d'histoire naturelle de Luxembourg Marche-aux-Poissons L-2345 Luxembourg MINISTERE DES AFFAIR.ES CULTURELLES TRAVAUX SCIENTIFIQUES DU MUSEE NATIONAL D'HISTOIRE NATURELLE DE LUXEMBOURG 21 Ecology and Vegetation of Mt Trikora New Guinea (lrian Jaya I Indonesia) by Jean-Marie MANGEN LuxeITibourg, 1993 « ... I know of no part of the world, the exploration of which is so flatter­ ing to the imagination, so likely to be fruitful in interesting results, whether to the naturalist, the ethonologist or the geographer, and alto­ gether so well calculated to gratify the enlivened curiosity of an adventur­ ous explorer, as the interior of New Guinea ... » J. Beete Jukes, H. M. S. 'Fly', 1942 (in: New Guinea, The last Unknown. Gavin Souter, 1963, p. 19) To the Dani Papuans of the Baliem Valley Contents Acknowledgements ................................................................................... 6 Abstract ..................................................................................................... 7 Preface ....................................................................................................... 9 CHAPTER I: General presentation I. The area and its exploration ..................................................... 11 II. The main vegetation types and altitud inal zonation ............... 18 CHAPTER II: The Physical Environment I. The geology and geomorphology .......................................... 31 II. The soils on Mt Trikora ......................................................... 43 III. The climate ............................................................................. 55 CHAPTER ID: The vegetation of Mt Trikora I. Survey methods ....................................................................... 65 II. Subalpine vegetation l. The forests ........................................................................... 69 2. The shrublands .............. : ..................................................... 76 3. The subalpine grasslands .................................................... 84 4. The mires ............................................................................. 88 5. The open rocky slope communities .................................... 98 III. Alpine vegetation l. The alpine dwarf shrub heath ........................................... 100 2. The alpine tussock grasslands........................................... 102 3. The Astelia alpina alpine herbfield .................................. 102 4. The alpine mire communities ........................................... 104 5. The alpine scree communities . .. .. .. .. ... ... .. .. l 05 6. The Rhacomitrium heath and related vegetation ............. 109 IV. Discussion ............................................................................. 1 I l CHAPTER IV: Phytogeography of Mt Trikora ............................... 119 Final comments ..................................................................................... 129 References . .. .. .. .. .. .. .. .. .. .. .. .. .. 131 Appendix I: Meteorological records from Wamena ........................ 147 Appendix II: Plants collected < 3000 m ............................................ 149 Appendix III: Flora of Mt Trikora: a checklist of species ............... 153 (>3000 m) Appendix IV: Phytosociological tables ............................................... 179 Appendix V: Distribution table of genera ......................................... 209 Appendix VI: Topographical scetch map of Mt Trikora Trav. sci. Mus. nat. hist. nat. Luxemb. 21, 1993 Acknowledgements The research for this work on the subalpine and alpine vegetation of Mt Trikora would not have been possible without the help of many people, either in New Guinea itself, or in Bogor (Indonesia), Toulouse (France), Leiden (The Netherlands) and Luxembourg. Hence I wish to acknowledge all the persons who contributed in any way to the fullfillment of this task. I am particularly grateful to Dr. F. Blasco, who enabled this work by accepting me as a student in the 'lnstitut de la Carte Internationale de la Vegetation' in Toulouse, France. Furthermore, I would like to thank with heart and hand the staff members and botanists of the Rijksherbarium for their valuable help in identifying the plants collected, in particular Max van Balgooy for permanent and unre­ served advice and guidance in the determinations. I am also greatly indebted to the readers of the manuscript, i.e. J.P.Pascal (Toulouse) for the original french text and W. Vink (Leiden) for the present publication. For the identifications of fossils, I am grateful to A.Blondeau ('Universite Pierre et Marie Curie', Paris) and J.Magnie ('Universite Paul Sabatier', Toulouse), and P.Buurman (Wageningen, The Netherlands) for his help with iron concretions from Mt Trikora.The soil samples have been analysed by A.Puraye ('Laboratoire de Contr6le et d'Essais des Services techniques de l' Agriculture,' Luxembourg) and the meteorological data from the Baliem Valley have been kindly provided by M. J.K.Tanawani from Wamena. Many thanks also to the scientists and staff of the 'Musee national d'histoire naturelle de Luxembourg' for their help on all occasions. During my visits in Indonesia, I made many friends to whom I am indebted for hospitality. I want to express my heartly thanks to all of them and especially to Mr. and Mrs. Purnajaya (Bogor) as well as to Mr. and Mrs. Zaini (Wamena). My field trips to New Guinea will remain engraved in my mind forever, due in particular to the help and kindness of the people of the Baliem Valley, who contributed to the success of the field work by innumerable tasks. Finally, I would like to thank my wife Nadine and my children, to whom this work has asked many sacrifices, especially during my absence for field work. 6 Trav. sci. Mus. nat. hist. nac. Luxemb. 21, 1993 Ecology and Vegetation of Mt Trikora, New Guinea (lrian Jaya) by Jean-Marie MANGEN Abstract Chapter I: After a presentation of the main geographical features, the author retraces the history of the scientific exploration of Mt Trikora, New Guinea (Irian Jaya), and describes the altitudinal zonation of the vegetation. Chapter II: The physical environment is described; geology and geomorphology, soils and climate (regional, local) are analysed and com­ mented. Chapter III: The study of the vegetation of the subalpine and alpine zones (> 3000 m) is based on 86 phytosociological plots. 26 different vegetation communities have been recognized. The subalpine vegetation is divided into forests (2 types), shrublands (2), heaths (2), grasslands (2), berblands (1), mire associations (5) and open rocky slope communities (3). In the alpine zone, the author distinguishes and describes alpine heath formations (1), grasslands (1), herbfields (1) and mires (2); the rock surfaces and alpine screes (2) are also studied. Chapter IV: In the last part, the flora of Mt Trikora is compared to those of other mountains in New Guinea and to Mt Kinabalu, Borneo. The author comm~nts some hypotheses on the origin and distribution of the subalpine and alpine vegetation in New Guinea. Appendices : The reader may find meteorological data from Wamena (Baliem Valley), a list of plants collected by the author in the Baliem Valley and beneath Mt Trikora trail below 3000 m, a list of plants collected by Brass et al. and by the author above 3000 m, a table comparing the geographical distribution of genera in the highlands of New Guinea; and finally a physiographical scetch map of Mt Trikora and surroundings. 7 Trav. sci. Mus. nat. hist. nat. Luxemb. 21 , 1993 Resume Chapitre I: Apres une presentation du contexte geographique, l'auteur retrace l'historique de l'exploration scientifique du Mt Trikora. Il donne ensuite l'etagement en altitude de la vegetation. Chapitre II: Les facteurs geologique et climatique regionaux et locaux, ainsi que pedologiques sont etudies et commentes. Chapitre III: L'etude de la vegetation porte sur Jes etages subalpin et alpin (> 3000 m). 86 releves phytosociologiques ont ete effectues sur des placettes de taille variable selon Jes types de formation. En tout, 26 communautes vegetales differentes ont ete reconnues. La vegetation subalpine est subdivisee en formations ligneuses, formations herbacees et groupements rupicoles. L'auteur analyse ainsi parmi les formations ligneuses, une foret de transition aLibocedrus papuana, la foret subalpine dominee par desEricaceae , 2 types de foutTes altimontains et 2 types de landes. Les formations herbacees comprennent 2 types de savanes, une pelouse discontinue basse, 5 types de bas marais et 2 mouillieres. Trois groupements rupicoles ont ete retenus. Dans l'etage alpin sont reconnus et decrits une lande basse, et 4 formations herbacees (savanes, pelouse basses, et mouillieres). Les groupements rupicoles et ceux des pierriers/eboulis (2 types) sont egalement etudies. Chapitre IV: La derniere partie analyse les affinites et particularites phytogeographiques de la flore du Mt Trikora. Les donnees sont comparees avec celles d' autres massifs montagneux de Nouvelle-Guinee, et celle du Mt Kinabalu, a Borneo. L'auteur commente certaines hypotheses sur l'origine et la distribution de la vegetation altimontaine en