Skip to main content

Advertisement

SpringerLink
Log in

Spatial variation in plant interactions across a severity gradient in the sub-Antarctic

  • Community Ecology - Original Paper
  • Published:
Oecologia Aims and scope Submit manuscript

Abstract

The stress–gradient hypothesis predicts that the intensity of interspecific positive interactions increases along environmental severity (i.e. stress and disturbance) gradients faster than the intensity of negative interactions. This study is the first to test if the stress–gradient hypothesis is supported for a location in the climatically extreme and species-poor sub-Antarctic. To do so, we investigate the fine-scale spatial distribution of plant species across altitude- and aspect-related abiotic severity gradients on a scoria cone on Marion Island. A clear altitudinal severity gradient was observed across the scoria cone, with lower temperatures, stronger winds and greater soil movement at higher altitudes. The altitudinal severity gradient was matched by stronger interspecific spatial association between the four dominant species at higher altitudes and in areas of lower vegetation cover. This suggests that, relative to the intensity of competition, the intensity of facilitation is greater under more severe conditions, supporting the stress–gradient hypothesis at the community level (i.e. for multiple pairs of species) and corroborating its usefulness for predicting variation in plant interactions at high latitudes and altitudes. Furthermore, the directional intraspecific aggregation and interspecific association plant cover patterns found within the gradient suggest that protection from the prevailing wind and from burial by loose substrate are the dominant facilitative mechanisms. Thus, plants benefit from the presence of neighbours when they provide shelter and substrate stability, and the relative intensity of this positive interaction is greatest at higher altitudes, and varies between species pairs. This study, therefore, not only provides support for the stress–gradient hypothesis in the sub-Antarctic, but also demonstrates fine-scale directional spatial patterns between multiple species nested within the severity gradient.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Fig. 1
Fig. 2
Fig. 3
Fig. 4

Similar content being viewed by others

References

  • Alftine KJ, Malanson GP (2004) Directional positive feedback and pattern at an alpine tree line. J Veg Sci 15:3–12

    Article  Google Scholar 

  • Arroyo MTK, Cavieres LA, Peñaloza A, Arroyo-Kalin MA (2003) Positive associations between the cushion plant Azorella monantha (Apiaceae) and alpine plant species in the Chilean Patagonian Andes. Plant Ecol 169:121–129

    Article  Google Scholar 

  • Austin MP, Cunningham RB, Fleming PM (1984) New approaches to direct gradient analysis using environmental scalars and statistical curve-fitting procedures. Vegetatio 55:11–27

    Article  Google Scholar 

  • Badano EI, Cavieres LA, Molina-Montenegro MA, Quiroz CL (2005) Slope aspect influences plant association patterns in the Mediterranean matorral of central Chile. J Arid Environ 62:93–108

    Article  Google Scholar 

  • Bate GC, Smith VR (1983) Photosynthesis and respiration in the sub-Antarctic tussock grass Poa cookii. New Phytol 95:533–543

    Article  Google Scholar 

  • Bertness MD, Callaway RM (1994) Positive interactions in communities. Trends Ecol Evol 9:191–193

    Article  Google Scholar 

  • Boelhouwers J, Holness S, Sumner P (2000) Geomorphological characteristics of small debris flows on Junior’s Kop, Marion Island, maritime sub-Antarctic. Earth Surf Proc Land 25:341–352

    Article  Google Scholar 

  • Boelhouwers J, Holness S, Sumner P (2003) The maritime sub-Antarctic: a distinct periglacial environment. Geomorphology 52:39–55

    Article  Google Scholar 

  • Brooker RW (2006) Plant–plant interactions and environmental change. New Phytol 171:271–284

    Article  PubMed  Google Scholar 

  • Brooker RW, Callaghan TV (1998) The balance between positive and negative plant interactions and its relationship to environmental gradients: a model. Oikos 81:196–207

    Article  Google Scholar 

  • Brooker RW et al. (2008) Facilitation in plant communities: the past, the present, and the future. J Ecol 96:18–34

    Article  Google Scholar 

  • Bruno JF, Stachowicz JJ, Bertness MD (2003) Inclusion of facilitation into ecological theory. Trends Ecol Evol 18:119–125

    Article  Google Scholar 

  • Bullock JA, Moy IL (2004) Plants as seed traps: inter-specific interference with dispersal. Acta Oecol 25:35–41

    Article  Google Scholar 

  • Callaway RM (1998) Are positive interactions species-specific? Oikos 82:202–207

    Article  Google Scholar 

  • Callaway RM, Walker LR (1997) Competition and facilitation: a synthetic approach to interactions in plant communities. Ecology 78:1958–1965

    Google Scholar 

  • Callaway RM et al. (2002) Positive interactions among alpine plants increase with stress. Nature 417:844–848

    Google Scholar 

  • Carlsson BÅ, Callaghan TV (1991) Positive plant interactions in tundra vegetation and the importance of shelter. J Ecol 79:973–983

    Article  Google Scholar 

  • Cavieres LA, Arroyo MTK, Peñaloza A, Molina-Montenegro MA, Torres C (2002) Nurse effect of Bolax gummifera cushion plants in the alpine vegetation of the Chilean Patagonian Andes. J Veg Sci 13:547–554

    Article  Google Scholar 

  • Cavieres LA, Badano EI, Sierra-Almeida A, Gomez-Gonzalez S, Molina-Montenegro MA (2006) Positive interactions between alpine plant species and the nurse cushion plant Laretia acaulis do not increase with elevation in the Andes of central Chile. New Phytol 169:59–69

    Article  PubMed  Google Scholar 

  • Choler P, Michalet R, Callaway RM (2001) Facilitation and competition on gradients in alpine plant communities. Ecology 82:3295–3308

    Google Scholar 

  • Ennos AR (1997) Wind as an ecological factor. Trends Ecol Evol 12:108–111

    Article  Google Scholar 

  • Fehmi JS, Bartolome JW (2001) A grid-based method for sampling and analysing spatially ambiguous plants. J Veg Sci 12:467–472

    Article  Google Scholar 

  • Franks SJ, Peterson CJ (2003) Burial disturbance leads to facilitation among coastal dune plants. Plant Ecol 168:13–21

    Article  Google Scholar 

  • Frenot Y, Gloaguen J-C, Cannavacciuolo M, Bellido A (1998) Primary succession on glacier forelands in the sub-Antarctic Kerguelen Islands. J Veg Sci 9:75–84

    Article  Google Scholar 

  • García LV (2004) Escaping the Bonferroni iron claw in ecological studies. Oikos 105:657–663

    Article  Google Scholar 

  • Gavilán RG, Sanchez-Mata D, Escudero A, Rubio A (2002) Spatial structure and interspecific interactions in Mediterranean high mountain vegetation (Sistema Central, Spain). Israel J Plant Sci 50:217–228

    Article  Google Scholar 

  • Gómez-Aparicio L, Zamora R, Gómez JM, Hódar JA, Castro J, Baraza E (2004) Applying plant facilitation to forest restoration: a meta-analysis of the use of shrubs as nurse plants. Ecol Appl 14:1128–1138

    Article  Google Scholar 

  • Haase P (2001) Can isotropy vs. anisotropy in the spatial association of plant species reveal physical vs. biotic facilitation? J Veg Sci 12:127–136

    Article  Google Scholar 

  • Hacker SD, Gaines SD (1997) Some implications of direct positive interactions for community species diversity. Ecology 78:1990–2003

    Article  Google Scholar 

  • Heilbronn TD, Walton DWH (1984) Plant colonization of actively sorted stone stripes in the subAntarctic. Arctic Alpine Res 16:161–172

    Article  Google Scholar 

  • Holness SD (2004) Sediment movement rates and processes on cinder cones in the maritime Subantarctic (Marion Island). Earth Surf Proc Land 29:91–103

    Article  Google Scholar 

  • Huntley BJ (1970) Altitudinal distribution and phenology of Marion Island vascular plants. Tydsk vir Natuurwetenskap 10:255–262

    Google Scholar 

  • Huntley BJ (1971) Vegetation. In: van Zinderen Bakker EM Sr, Winterbottom JM, Dyer RA (eds) Marion and Prince Edward Islands: report on the South African biological and geological expeditions, 1965–1966. A.A. Balkema, Cape Town, South Africa, pp 98–160

  • Kikvidze Z et al (2005) Linking patterns and processes in alpine plant communities: a global study. Ecology 86:1395–1400

    Article  Google Scholar 

  • Klanderud K, Totland O (2004) Habitat dependent nurse effects of the dwarf-shrub Dryas octopetala on alpine and arctic plant community structure. Ecoscience 11:410–420

    Google Scholar 

  • Lancaster J, Downes BJ (2004) Spatial point pattern analysis of available and exploited resources. Ecography 27:94–102

    Article  Google Scholar 

  • le Roux PC (2008) Climate and climate change. In: Chown SL, Froneman PW (eds) The Prince Edward Islands: land–sea interactions in a changing ecosystem. African SunMedia, Stellenbosch (in press)

  • le Roux PC, McGeoch MA (2008) Changes in climate extremes, variability and signature on sub-Antarctic Marion Island. Clim Change 86:309–329

    Article  Google Scholar 

  • Lortie CJ, Callaway RM (2006) Re-analysis of meta-analysis: support for the stress–gradient hypothesis. J Ecol 94:7–16

    Article  Google Scholar 

  • Maestre FT, Valladares F, Reynolds JF (2005) Is the change of plant–plant interactions with abiotic stress predictable? A meta-analysis of field results in arid environments. J Ecol 93:748–757

    Article  Google Scholar 

  • Maestre FT, Valladares F, Reynolds JF (2006) The stress–gradient hypothesis does not fit all relationships between plant–plant interactions and abiotic stress: further insights from arid environments. J Ecol 94:17–22

    Article  Google Scholar 

  • Michalet R et al. (2006) Do biotic interactions shape both sides of the humped-back model of species richness in plant communities? Ecol Lett 9:767–773

    Google Scholar 

  • Pammenter NW, Drennan PM, Smith VR (1986) Physiological and anatomical aspects of photosynthesis of two Agrostis species at a sub-Antarctic island. New Phytol 102:143–160

    Article  Google Scholar 

  • Perry JN (1998) Measures of spatial pattern for counts. Ecology 79:1008–1017

    Google Scholar 

  • Perry JN, Dixon PM (2002) A new method to measure spatial association for ecological count data. Ecoscience 9:133–141

    Google Scholar 

  • Pugnaire FI, Luque MT (2001) Changes in plant interactions along a gradient of environmental stress. Oikos 93:42–49

    Article  Google Scholar 

  • Quinn GP, Keough MJ (2002) Experimental design and data analysis for biologists, 1st edn. Cambridge University Press, Cambridge

    Google Scholar 

  • Reichman OJ (1984) Spatial and temporal variation of seed distributions in Sonoran Desert soils. J Biogeogr 11:1–11

    Article  Google Scholar 

  • Scheffer M, Holmgren M, Brovkin V, Claussen M (2005) Synergy between small- and large-scale feedbacks of vegetation on the water cycle. Glob Change Biol 11:1003–1012

    Article  Google Scholar 

  • Scott JJ, Bergstrom DM (2005) Vegetation of Heard Island and the McDonald Islands. In: Green K, Woehler EJ (eds) Heard Island: Southern Ocean Sentinel. Surrey Beatty & Sons, Chipping Norton, UK, pp 69–90

  • Smith VR (1987) The environment and biota of Marion Island. S Afr J Sci 83:211–220

    Google Scholar 

  • Smith VR, Mucina L (2006) Vegetation of Marion and Prince Edward Islands. In: Mucina L, Rutherford MC (eds) Vegetation of South Africa, Lesotho and Swaziland: Strelitzia, vol 19. South African National Biodiversity Institute, Pretoria, pp 698–723

  • Smith VR, Steenkamp M (1990) Climatic change and its ecological implications at a sub-Antarctic island. Oecologia 85:14–24

    Article  Google Scholar 

  • Tielbörger K, Kadmon R (2000) Temporal environmental variation tips the balance between facilitation and interference in desert plants. Ecology 81:1544–1553

    Google Scholar 

  • Tirado R, Pugnaire FI (2003) Shrub spatial aggregation and consequences for reproductive success. Oecologia 136:296–301

    Article  PubMed  Google Scholar 

  • Veblen TT, Ashton DH, Schlegel FM, Veblen AT (1977) Plant succession in a timberline depressed by vulcanism in south-central Chile. J Biogeogr 4:275–294

    Article  Google Scholar 

  • Warren Wilson J (1959) Notes on wind and its effects in Arctic–alpine vegetation. J Ecol 47:415–427

    Article  Google Scholar 

Download references

Acknowledgments

Joe Perry, Kelvin Conrad and Peter Haase are thanked for making the SADIE and SPPA software available. Jenna Snyman, Quintin Schutte, Ethel Phiri, Asanda Phiri, Lizel Hugo, Zipho Buwa and Jacques Deere are thanked for assisting with fieldwork. Jesse Kalwij, Ruan Veldtman, Sue Milton and two anonymous reviewers are thanked for helpful comments on the manuscript. Financial support was provided by the South African National Research Foundation, the South African National Antarctic Program (Grant number 2069543 and SNA 2004070900002) and the University of Stellenbosch. This research complied with the current laws of South Africa.

Author information

Authors and Affiliations

  1. Department of Conservation Ecology and Entomology, University of Stellenbosch, Private Bag X1, Matieland, 7602, South Africa

    Peter C. le Roux & Melodie A. McGeoch

Authors
  1. Peter C. le Roux
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Melodie A. McGeoch
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to Peter C. le Roux.

Additional information

Communicated by Melinda Smith.

Electronic supplementary material

Below is the link to the electronic supplementary material.

ESM1 (PDF 809 kb)

Rights and permissions

Reprints and permissions

About this article

Cite this article

le Roux, P.C., McGeoch, M.A. Spatial variation in plant interactions across a severity gradient in the sub-Antarctic. Oecologia 155, 831–844 (2008). https://doi.org/10.1007/s00442-007-0954-1

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s00442-007-0954-1

Keywords

Search

Navigation