Linking Spatial Patterns to Forest Ecological Processes by Using Spatial Statistical Methods
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University of Montana ScholarWorks at University of Montana Graduate Student Theses, Dissertations, & Professional Papers Graduate School 2005 Linking spatial patterns to forest ecological processes by using spatial statistical methods Alex Fajardo-YaÌ?ñez The University of Montana Follow this and additional works at: https://scholarworks.umt.edu/etd Let us know how access to this document benefits ou.y Recommended Citation Fajardo-YaÌ?ñez, Alex, "Linking spatial patterns to forest ecological processes by using spatial statistical methods" (2005). Graduate Student Theses, Dissertations, & Professional Papers. 9578. https://scholarworks.umt.edu/etd/9578 This Dissertation is brought to you for free and open access by the Graduate School at ScholarWorks at University of Montana. It has been accepted for inclusion in Graduate Student Theses, Dissertations, & Professional Papers by an authorized administrator of ScholarWorks at University of Montana. For more information, please contact [email protected]. Maureen and Mike MANSFIELD LIBRARY The University of Montana Permission is granted by the author to reproduce this material in its entirety, provided that this material is used for scholarly purposes and is properly cited in published works and reports. * * Please check "Yes" or "No" and provide signature** Yes, I grant permission 7 ^ No, I do not grant permission __________ Author's Signature: Date: Any copying for commercial purposes or financial gain may be undertaken only with the author's explicit consent. 8/98 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. LINKING SPATIAL PATTERNS TO FOREST ECOLOGICAL PROCESSES BY USING SPATIAL STATISTICAL METHODS by Alex Fajardo-Yanez B.Sc. Universidad de Concepcion, Chile, 1996 M.Sc. Wageningen Universiteit, The Netherlands, 2000 Presented in partial fulfillment of the requirements for the degree of Doctor of Philosophy The University of Montana December 2005 Approved by: Chairman Dean, Graduate School I 2* i Date Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. UMI Number: 3199237 INFORMATION TO USERS The quality of this reproduction is dependent upon the quality of the copy submitted. Broken or indistinct print, colored or poor quality illustrations and photographs, print bleed-through, substandard margins, and improper alignment can adversely affect reproduction. In the unlikely event that the author did not send a complete manuscript and there are missing pages, these will be noted. Also, if unauthorized copyright material had to be removed, a note will indicate the deletion. ® UMI UMI Microform 3199237 Copyright 2006 by ProQuest Information and Learning Company. All rights reserved. This microform edition is protected against unauthorized copying under Title 17, United States Code. ProQuest Information and Learning Company 300 North Zeeb Road P.O. Box 1346 Ann Arbor, Ml 48106-1346 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Fajardo-Yanez, Alex, Ph.D., December 2005 Forestry Linking spatial patterns to forest ecological processes by using spatial statistical methods Chairman: John M. Goodbum While spatial patterns have long been recognized as important aspects of forest vegetation and site factors, the task of explaining patterns in relation to underlying processes has been more difficult. Advances in spatial statistical analysis are offering ecologists new strategies for examining spatial patterns that have the potential to better link observed patterns to processes. This dissertation project applied multiple methods of spatial statistical analysis to four field studies conducted in Montana (USA) and Chile (South America), including some novel approaches for examining causal factors and extending the utility of plot-based data. In the first study of natural stands of Nothofagus glauca in south-central Chile, analysis using Ripley’s Z-function indicated that the ecological status of N. glauca may vary from pioneer to gap strategist depending on site and stand conditions. On harsh sites, N. glauca seedlings displayed positive spatial associations with overstory trees, suggesting facilitation. To further examine bivariate associations observed between regeneration and overstory trees I studied ponderosa pine/Douglas-fir forests of western Montana. A new index was developed that quantifies the strength of association between canopy layers. This index considers the ratio between the value (Z 1.2 (t)) of the bivariate Z-function and the corresponding confidence envelope at a specified distance ( t). Larger index values indicate greater departures from the hypothesis of no spatial association, prompting further AN O VA comparisons among groups of plots differing in moisture availability. Seedlings of both ponderosa pine and Douglas-fir tend to be positively associated with overstory trees in drier sites, and negatively associated on moister sites. In a third study examining pine plantations in Patagonia, an effort to further discriminate between multiple factors influencing spatial patterns at different scales utilized a semivariogram approach to formulate stand development models for even-aged populations. In the fourth study, data from ponderosa pine restoration treatments in a randomized block design were weighted using a spatial A N O VA model to control for spatial auto-correlation, allowing expansion of the original design to examine age classes separately. This case study indicated that old trees responded positively to release from competition via harvesting, but that spring broadcast burning may reduce both growth and vigor. These various studies emphasize the importance of both spatial pattern description and the utility of statistical strategies for examining potential causal factors. ii Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. ACKNOWLEDGMENTS For this thesis project I was mainly funded by the USDA Mclntire-Stennis program, from the University of Montana College of Forestry and Conservation. I also owe special thanks to Jim Burchfield for providing extra funding for my trips to Chile. For logistic support in Montana, I thank the College of Forestry and Conservation, and Rolan Becker from the Flathead Indian Reservation; in Chile, many thanks to Mauricio Morales, Proyecto Bosque Nativo, San Fabian de Alico, and Rafael Eyzaguirre, Forestal Mininco, Coyhaique. I would like to thank my committee members for direction and support. I thank Paul Alaback for his advice on general ideas in forest ecology and specific ideas on Nothofagus temperate forests dynamics in Chile. Carl Fiedler for his kind support on the Lick Creek Experimental Area, through the setting and mapping of data, and also for the facilitation of instruments. Jonathan Graham for greatly improving my knowledge in the fascinating field of spatial statistics, and his restless enthusiasm in soccer conversations. Kelsey Milner for his few but great advice: “you have to do what you like the most”, which can appear as general but is the key for everything. I would like to thank John Goodbum for being responsible for my arrival to this College. He also gave me the opportunity to pursue my ideas on spatial statistics as a plausible project to carry out. Through all this time, in spite of sometimes having different perspectives on forestry and ecology, we managed to bring out this piece of scientific work. I would like to thank particularly Eliot Mclntire for his lucid and inspirational help and dedication in developing new ideas on the link between forest ecology and spatial statistics, and for his enthusiasm in developing science at a high level; Chapter 4 is rooted iii Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. in rich discussions with him. I want to thank to Celine Boisvenue for listening to my research questions and for her clever advice. For friendship, advice, scientific and non- scientific conversations, field assistance and for their enthusiasm on real football (soccer) and beer, I am very grateful to Jose Hierro and Michael Hofmann: unforgettable times. I would like to thank Adam Johnson, Christopher Vincent and Jason Raczkiewicz for field assistance. Back in Chile there is another bunch of people to acknowledge. First of all, I would like to thank my immediate family, my father, Fermin, and my mother, Gilda, and my sisters, Alejandra and Cristina, who have always supported me in my research and traveling vocation, and also for their logistic aid. I am grateful to Ceferino Albomoz, Proyecto Bosque Nativo, for his transportation help and his talkative barbecues. I would like to thank Julio Quitral and Marcelo Martinez for his dedicated assistance in the field. I also would like to thank Lohengrin Cavieres, Universidad de Concepcion, for his support and research discussions. For the Patagonia fieldwork experience, I am grateful to Aliro Gascon for his priceless support and friendship, and transportation. I also would like to thank the people of Forestal Minico, Coyhaique, for transportation and dedicated field assistance. iv Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Table of Contents Fajardo-Yanez, Alex, Ph.D., December 2005 Forestry ...........................................................