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Plant Ecology

, Volume 201, Issue 1, pp 11–22 | Cite as

Effects of introduced ungulates on forest understory communities in northern Patagonia are modified by timing and severity of stand mortality

  • María Andrea RelvaEmail author
  • Christian López Westerholm
  • Thomas Kitzberger
Article

Abstract

Natural disturbances such as fires, windstorms, floods, and herbivory often act on plant communities, affecting their structure and the abundance and composition of their species. Most research has focused on the effects of single disturbances on plant communities whereas the synergistic effects of several disturbances have received less attention. In this study, we evaluated how timing and severity of tree mortality modified plant use by introduced deer and early post-mortality successional trajectories in northern Patagonian conifer forests. We sampled understory composition and deer use in Austrocedrus chilensis (ciprés de la cordillera) forest stands undergoing varying timing and severity of forest mortality as reconstructed using dendroecological techniques. In addition, we evaluated the effect of fallen logs on plant composition and deer use of plants by monitoring areas of massive dieback where fallen logs had been removed for fire hazard reduction, and nearby control areas not subjected to such removal. Stepwise regression analyses showed that history and severity of tree mortality strongly influence plant composition and deer use of plants. For deer use (with pellet counts and browsing index as response variables), results showed a positive relationship with degree of stand mortality and a negative relationship with cover of fallen logs. Similarly, cover of unpalatable shrub species was explained by canopy mortality history, whereas cover of palatable shrub species was positively associated with severity of canopy mortality. In areas where fallen logs had been removed, pellet counts were six times higher than those in control areas. Though total shrub species cover was similar between log removal and control areas, proportion of unpalatable shrubs increased in areas where fallen logs had been removed. In conclusion, deer use of plants was strongly limited by tall fallen logs, allowing palatable species to establish and grow. Fallen log removal accelerated deer entrance and changed understory composition toward more browse-resistant and unpalatable species. These results underscore the importance of considering the dynamics (timing, severity, and extent) of fallen woody debris influencing understory herbivory and post-disturbance succession. In addition, experimental results underpin the importance of maintaining snags and large woody debris in disturbed landscapes where salvage logging is a routine procedure.

Keywords

Austrocedrus chilensis Browsing Disturbance Exotic deer Forest decline 

Notes

Acknowledgments

We wish to thank Diego Vazquez for valuable comments on the manuscript, park rangers of Isla Victoria (Damián Mujica, Lidia Serantes, Domingo Nuñez, and Carina Pedrozo) for helping us in many ways. Delegación Técnica Regional and Intendencia del Parque Nacional Nahuel Huapi assisted us with working permits, and Cau Cau and Mares Sur with transportation. We are especially grateful to Juan Gowda for helping on cross-section tree extractions, and Eduardo Zattara for his field assistance. Daniel Simberloff revised several versions of this manuscript improving the language and clarity. This research was supported by a postdoctoral fellowship to M.A.R from Consejo Nacional de Ciencia y Técnica of Argentina CONICET and by funds from Universidad Nacional del Comahue. Foundation Linnaeus-Palme funded C.L.W scholarship.

References

  1. Allan C, Stewart G, Allen R (1997) Long term influences of deer browsing on forest health and conservation values of the Kaweka Range. Final Report Lincoln University and WWF, CanterburyGoogle Scholar
  2. Allen RB, McLennan MJ (1983) Indigenous forest survey manual: two inventory methods. New Zealand For Serv FRI Bulletin no. 48Google Scholar
  3. Anziano AF (1962) Acción de los animales sobre la flora. Anales de Parques Nacionales, Administración de Parques Nacionales. Tomo IX:107–112Google Scholar
  4. Barros VR, Cordon VH, Moyano C, Mendez R, Forquera JC, Pizzio O (1988) Carta de precipitación de la zona oeste de las provincias de Río Negro y Neuquén. Primera contribución (1972–1981). Facultad de Ciencias Agrarias. Universidad Nacional del Comahue, Cinco SaltosGoogle Scholar
  5. Barrios Garcia Moar MN (2005) Patrones de daño, uso actual y tendencia histórica de la abundancia de ciervos introducidos en bosques nativos de Isla Victoria, Patagonia, Argentina. Licenciate Dissertation. Universidad Nacional del Comahue, Bariloche, ArgentinaGoogle Scholar
  6. Bergquist J, Örlander G (1998) Browsing damage by roe deer on Norway spruce seedlings planted on clearcuts of different ages. 1. Effect of slash removal, vegetation development, and roe deer density. For Ecol Manage 105:283–293CrossRefGoogle Scholar
  7. Cali SG (1996) Austrocedrus: estudio de los anillos de crecimiento y su relación con la dinámica del “mal del ciprés” en el Parque Nacional Nahuel Huapi, Argentina. Licenciate Dissertation. Universidad Nacional del Comahue, Bariloche, ArgentinaGoogle Scholar
  8. Cavieres LA, Fajardo A (2005) Browsing by guanaco (Lama guanicoe) on Nothofagus pumilio forest gaps in Tierra del Fuego, Chile. For Ecol Manage 204:237–248CrossRefGoogle Scholar
  9. de Chantal M, Ganström A (2007) Aggregations of dead wood after wildfire act as browsing refugia for seedlings of Populus tremula and Salix caprea. For Ecol Manage 250(1):3–8CrossRefGoogle Scholar
  10. De Pietri DE (1992) Alien shrub in a National Park: can they help in the recovery of natural degraded forest? Biol Conserv 62:27–130. doi: 10.1016/0006-3207(92)90933-E Google Scholar
  11. Ezcurra C, Brion C (2005) Plantas del Nahuel Huapi. Catálogo de la Flora Vascular del Parque Nacional Nahuel Huapi, ArgentinaGoogle Scholar
  12. Filip GM, Rosso PH (1999) Cypress mortality (mal del ciprés) in the Patagonia Andes: comparison with similar forest disease and declines in North America. Eur J Forest Pathol 29:89–96. doi: 10.1046/j.1439-0329.1999.00133.x CrossRefGoogle Scholar
  13. Flueck WT, Smith-Flueck JA, Naumann CM (2003) The current distribution of red deer (Cervus elaphus) in southern Latin America. Z Jagdwiss 49:112–119. doi: 10.1007/BF02190451 CrossRefGoogle Scholar
  14. Gallopin GC, Martín CE, Mermoz MA (2005) Impacto de la ganadería en la cuenca del río Manso Superior. Parte I: Bosque de Ñire con Laura. Anales de Parques Nacionales, Administración de Parques Nacionales. Tomo XVII:9–36Google Scholar
  15. Greslebin A, Hansen E (2006) Novedades sobre el mal del ciprés. Patagonia For 12(1):11–14Google Scholar
  16. Hanley TAR, Robbins CT, Spalinger DE (1989) Forest habitats and the nutritional ecology of Sitka black-tailed deer: a research synthesis with implications for forest management. USDA For Serv Res Pap PNW-GTR-230Google Scholar
  17. Havrylenko M, Rosso PH, Fontenla S (1989) Austrocedrus chilensis: contribución al estudio de su mortalidad en Argentina. Bosque 10(1):29–36Google Scholar
  18. Hobbs NT (1996) Modification of ecosystems by ungulates. J Wildl Manage 60(4):695–713. doi: 10.2307/3802368 CrossRefGoogle Scholar
  19. Holmes R (1983) Computer-assisted quality control in tree-ring dating and measurement. Tree-ring Bull 43:69–75Google Scholar
  20. Jefferies RL, Klein D, Shaver GR (1994) Vertebrate herbivores and northern plant communities: reciprocal influences and responses. Oikos 71:193–206. doi: 10.2307/3546267 CrossRefGoogle Scholar
  21. Kitzberger T, Veblen T, Villalba R (2000a) Métodos dendroecológicos y sus aplicaciones en estudios de dinámica de bosques templados de Sudamérica. In: Roig FA (ed) Dendrocronología en América Latina. EDIUNC, Universidad de Cuyo, Mendoza, Argentina, pp 17–78Google Scholar
  22. Kitzberger T, Steinaker D, Veblen T (2000b) Effects of climatic variability on facilitation of tree establishment in northern Patagonia. Ecology 81(7):1914–1924Google Scholar
  23. Koutché V (1942) Estación Forestal de Puerto Anchorena, Isla Victoria; su organización y trabajos. Ministerio de Agricultura, Dirección de Parques Nacionales, Buenos Aires, ArgentinaGoogle Scholar
  24. Kupferschmid A, Bugmann H (2005) Effect of microsites, logs and ungulate browsing on Picea abies regeneration in a mountain forest. For Ecol Manage 205:251–265CrossRefGoogle Scholar
  25. La Manna L, Rajchenberg M (2004) The decline of Austrocedrus chilensis in Patagonia, Argentina: soil features as predisposing factors. For Ecol Manage 190:345–357CrossRefGoogle Scholar
  26. La Manna L, Bava J, Collantes M, Rajchenberg M (2006) Características estructurales de los bosques de Austrocedrus chilensis afectados por “mal del ciprés” en Patagonia, Argentina. Bosque 27(2):135–145Google Scholar
  27. La Manna L, Matteucci SD, Kitzberger T (2008) Abiotic factors related to the incidence of the Austrocedrus chilensis disease syndrome at a landscape scale. For Ecol Manage 256:1087–1095CrossRefGoogle Scholar
  28. Loguercio G, Rajchenberg M (2004) El “mal del ciprés” y la silvicultura del ciprés de la cordillera. In: Arturi MF, Frangi JL, Goya JF (eds) Ecología y Manejo de los Bosques de Argentina. EDULP, Universidad Nacional de La Plata, La Plata, ArgentinaGoogle Scholar
  29. Mayle BA, Peace AJ, Gill RMA (1999) How many deer? A field guide to estimating deer population size. Field Book 18. Forestry Commission, EdinburghGoogle Scholar
  30. Muñoz A, González M (2006) Aristotelia chilensis (Mol) Stuntz. In: Donoso C (ed) Las especies arbóreas de los bosques templados de Chile y Argentina. Autoecología, Cuneo Ediciones, pp 166–172Google Scholar
  31. Nyberg JB (1990) Interaction of timber management with deer and elk. In: Nyberg JB, Janz DW (eds) Deer and elk habitat as in coastal forests of Southern British Columbia. BC Ministry of Forests and Ministry of Environment, Special Report 5, pp 99–131Google Scholar
  32. Peterson CJ, Pickett STA (2000) Patch type influences on regeneration in a western Pennsylvania, USA, catastrophic windthrow. Oikos 90:489–500. doi: 10.1034/j.1600-0706.2000.900307.x CrossRefGoogle Scholar
  33. Pickett STA, White PS (1985) The ecology of natural disturbance and patch dynamics. Academic Press, OrlandoGoogle Scholar
  34. Pulido FJ, Díaz B, Martínez Pastur G (2000) Incidencia del ramoneo del guanaco (Lama guanicoe Müller) sobre la regeneración temprana en bosques de lenga (Nothofagus pumilio (Poepp et Endl) Krasser) de Tierra del Fuego, Argentina. Investigación Agraria. Sistemas Recursos Forestales 9(2):381–394Google Scholar
  35. Rebertus AJ, Kitzberger T, Veblen T, Roovers LM (1997) Blowdown history and landscape patterns in the Andes of Tierra del Fuego, Argentina. Ecology 78:678–692CrossRefGoogle Scholar
  36. Relva MA, Caldiz M (1998) Composición estacional de la dieta de ciervos exóticos en Isla Victoria, P.N. Nahuel Huapi, Argentina. Gayana (Zool) 62(2):101–108Google Scholar
  37. Relva MA, Veblen T (1998) Impacts of introduced large herbivores on Austrocedrus chilensis forests in northern Patagonia, Argentina. For Ecol Manage 108:27–40CrossRefGoogle Scholar
  38. Ripple WJ, Larsen EJ (2001) The role of postfire coarse woody debris in Aspen regeneration. West J Appl For 16(2):61–64Google Scholar
  39. Russell FL, Zippin DB, Fowler NL (2001) Effects of White-tailed deer (Odocoileus virginianus) on plants, plant populations and communities: a review. Am Midl Nat 146:1–26. doi: 10.1674/0003-0031(2001)146[0001:EOWTDO]2.0.CO;2 CrossRefGoogle Scholar
  40. Schreiner EG, Krueger KA, Happe PJ, Houston DB (1996) Understory patch dynamics and ungulate herbivory in old-growth forest of Olympic National Park, Washington. Can J Res 26:255–265. doi: 10.1139/x26-029 CrossRefGoogle Scholar
  41. Simberloff D, Relva MA, Nuñez M (2003) Introduced species and management of a Nothofagus/Austrocedrus forest. Environ Manage 31:263–275. doi: 10.1007/s00267-002-2794-4 PubMedCrossRefGoogle Scholar
  42. Stokes MA, Smiley TL (1968) An introduction to tree-ring dating. The University of Chicago Press, ChicagoGoogle Scholar
  43. Stuth JW (1991) Foraging behaviour. In: Heitschmidt RK, Stuth JW (eds) Grazing management. An ecological perspective. Timber Press, Oregon, pp 65–83Google Scholar
  44. Thomas JW, Black H, Scherzinger RJ, Pedersen RJ (1979) Deer and Elk. In: Thomas JW (ed) Wildlife habitats in managed forest. The Blue Mountains of Oregon and Washington. USDA For Serv Agriculture Handbook 553, pp 104–147Google Scholar
  45. Vázquez D (2002a) Interaction among introduced ungulate, plants and pollinators: a field study in the temperate forest of Southern Andes. PhD Dissertation, University of Tennessee, Knoxville, UsaGoogle Scholar
  46. Vázquez D (2002b) Multiple effects of introduced mammalian herbivores in a temperate forest. Biol Invasions 4:175–191. doi: 10.1023/A:1020522923905 CrossRefGoogle Scholar
  47. Veblen TT, Lorenz DC (1987) Post-fire stand development of Austrocedrus -Nothofagus forest in northern Patagonia. Vegetatio 71:113–126Google Scholar
  48. Veblen T, Mermoz M, Martín C, Ramilo E (1989) Effects of exotic deer on forest regeneration and composition in northern Patagonia. J Appl Ecol 26:711–724. doi: 10.2307/2404095 CrossRefGoogle Scholar
  49. White CA, Feller MC, Bayley S (2003) Predation risk and the functional response of elk-aspen herbivory. For Ecol Manage 181:77–97CrossRefGoogle Scholar
  50. Wisdom MJ, Vavra M, Boyd JM, Hemstrom MA, Ager AA, Johnson BK (2006) Understanding ungulate herbivory-episodic disturbances effects on vegetation dynamics: knowledge gaps and management needs. Wildl Soc Bull 34(2):283–292. doi: 10.2193/0091-7648(2006)34[283:UUHDEO]2.0.CO;2 CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media B.V. 2008

Authors and Affiliations

  • María Andrea Relva
    • 1
    Email author
  • Christian López Westerholm
    • 2
  • Thomas Kitzberger
    • 1
  1. 1.Laboratorio Ecotono, INIBIOMA-CONICETUniversidad Nacional del ComahueBarilocheArgentina
  2. 2.Plant Ecology and Systematics, Faculty of ScienceLund UniversityLundSweden

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