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Wise use of statistical tools in ecological field studies

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Abstract

The currently dominating hypothetico-deductive research paradigm for ecology has statistical hypothesis testing as a basic element. Classic statistical hypothesis testing does, however, present the ecologist with two fundamental dilemmas when field data are to be analyzed: (1) that the statistically motivated demand for a random and representative sample and the ecologically motivated demand for representation of variation in the study area cannot be fully met at the same time; and (2) that the statistically motivated demand for independence of errors calls for sampling distances that exceed the scales of relevant pattern-generating processes, so that samples with statistically desirable properties will be ecologically irrelevant. Reasons for these dilemmas are explained by consideration of the classic statistical Neyman-Pearson test procedure, properties of ecological variables, properties of sampling designs, interactions between properties of the ecological variables and properties of sampling designs, and specific assumptions of the statistical methods. Analytic solutions to problems underlying the dilemmas are briefly reviewed. I conclude that several important research objectives cannot be approached without subjective elements in sampling designs.

I argue that a research strategy entirely based on rigorous statistical testing of hypotheses is insufficient for field ecological data and that inductive and deductive approaches are complementary in the process of building ecological knowledge. I recommend that great care is taken when statistical tests are applied to ecological field data. Use of less formal modelling approaches is recommended for cases when formal testing is not strictly needed. Sets of recommendations, “Guidelines for wise use of statistical tools”, are proposed both for testing and for modelling. Important elements of wise-use guidelines are parallel use of methods that preferably belong to different methodologies, selection of methods with few and less rigorous assumptions, conservative interpretation of results, and abandonment of definitive decisions based a predefined significance level.

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References

  • Applegate R.D. (1999): Diversity and natural history observation in ecology.Oikos 87: 587–588.

    Article  Google Scholar 

  • Austin M.P. (1981): Permanent quadrats: an interface for theory and practice.Vegetatio 46–47: 1–10.

    Article  Google Scholar 

  • Bakker J.P., Olff H., Willems J.H. &Zobel M. (1996): Why do we need permanent plots in the study of long-term vegetation dynamics?J. Veg. Sci. 7: 147–156.

    Article  Google Scholar 

  • Bergeron Y. &Dansereau P.-R. (1993): Predicting the composition of Canadian southern boreal forest in different fire cycles.J. Veg. Sci. 4: 827–832.

    Article  Google Scholar 

  • Bonet A. &Pausas J.G. (2004): Species richness and cover along a 60-year chronosequence in old-fields of southeastern Spain.Pl. Ecol. 174: 257–270.

    Article  Google Scholar 

  • Crawley M.J. (2002):Statistical computing: an introduction to data analysis using S-Plus. Wiley, Chichester.

    Google Scholar 

  • Dahl E. (1957): Rondane: Mountain vegetation in South Norway and its relation to the environment.Skr. Norske Vidensk.-Akad. Oslo, Mat.-Naturvidensk. Kl. 1956: 3: 1–374.

    Google Scholar 

  • Dixon P.M., Ellison A.M. &Gotelli N.J. (2005): Improving the precision of estimates of the frequency of rare events.Ecology 86: 1114–1123.

    Article  Google Scholar 

  • Dungan J.L., Perry J.N., Dale M.R.T., Legendre P., Citron-Pousty S., Fortin M.-J., Jakomulska A., Miriti M. &Rosenberg M.S. (2002): A balanced view of scale in spatial statistical analysis.Ecography 25: 626–640.

    Article  Google Scholar 

  • Dutilleul P. (1993): Modifying thet-test for assessing the correlation between two spatial processes.Biometrics 49: 305–314.

    Article  Google Scholar 

  • Eilertsen O. (1991): Vegetation patterns and structuring processes in coastal shell-beds at Akerøya, Hvaler, SE Norway.Sommerfeltia 12: 1–90.

    Google Scholar 

  • Foster B.L. &Tilman D. (2000): Dynamic and static views of succession: testing the descriptive power of the chronosequence approach.Pl. Ecol. 146: 1–10.

    Article  Google Scholar 

  • Fransson S. (1972): Myrvegetation i sydvästra Värmland (Mire vegetation in SW Värmland).Acta Phytogeogr. Suec. 57: 1–133.

    Google Scholar 

  • Gjærevoll O. (1956): The plant communities of the Scandinavian alpine snow-beds.Kongel. Norske Vidensk. Selsk. Skr. (Trondheim) 1956: 1: 1–405.

    Google Scholar 

  • Halvorsen R. (1980): Numerical analysis and successional relationships of shell-bed vegetation at Akeroya, Hvaler, SE Norway.Norweg. J. Bot. 27: 71–95.

    Google Scholar 

  • Harper K.A., Bergeron Y., Drapeau P., Gauthier S. &de Grandpré L. (2005): Structural development following fire in black spruce boreal forest.Forest Ecol. Managem. 206: 293–306.

    Article  Google Scholar 

  • Hastie T., Tibshirani R. &Friedman J. (2001):The elements of statistical learning. Springer, New York.

    Google Scholar 

  • Heegaard E. (2002): A model of alpine species distribution in relation to snowmelt time and altitude.J. Veg. Sci. 13: 493–504.

    Article  Google Scholar 

  • Hurlbert S.H. (1984): Pseudoreplication and the design of ecological field experiments.Ecol. Monogr. 54: 187–211.

    Article  Google Scholar 

  • Hurlbert S.H. (2004): On misinterpretation of pseudoreplication and related matters: a reply to Oksanen.Oikos 104: 591–597.

    Article  Google Scholar 

  • Jonsson B.G. &Moen J. (1998): Patterns in species associations in plant communities: the importance of scale.J. Veg. Sci. 9: 327–332.

    Article  Google Scholar 

  • Kent M. &Balllard J. (1988): Trends and problems in the application of classification and ordination methods in plant ecology.Vegetatio 78: 109–124.

    Article  Google Scholar 

  • Lájer K. (2007): Statistical tests as inappropriate tools for data analysis performed on non-random samples of plant communities.Folia Geobot. 42: 115–122.

    Article  Google Scholar 

  • Lawesson J.E. &Oksanen J. (2002): Niche characteristics of Danish woody species as derived from coenoclines.J. Veg. Sci. 13: 279–290.

    Article  Google Scholar 

  • Lawton J.H. (1996): Patterns in ecology.Oikos 75: 145–147.

    Article  Google Scholar 

  • Lawton J.H. (1999): Are there general laws in ecology?Oikos 84: 177–192.

    Article  Google Scholar 

  • Legendre P. (1993): Spatial autocorrelation: trouble or new paradigm?Ecology 74: 1659–1673.

    Article  Google Scholar 

  • Legendre P., Dale M.R.T., Fortin M.-J., Gurevitch J., Hohn M. &Myers D. (2002): The consequences of spatial structure for the design and analysis of ecological field surveys.Ecography 25: 601–615.

    Article  Google Scholar 

  • Legendre P. &Legendre L. (1998):Numerical ecology, Ed. 2. Elsevier, Amsterdam.

    Google Scholar 

  • Lehmann E.L. (1993): The Fisher, Neyman-Pearson theories of testing hypotheses: one theory or two?J. Amer. Statist. Assoc. 88: 1242–1249.

    Article  Google Scholar 

  • Malmer N. (1962): Studies on mire vegetation in the Archaean area of Southwestern Götaland (South Sweden). I. Vegetation and habitat conditions on the Åkhult mire.Opera Bot. 7: 1: 1–322.

    Google Scholar 

  • Mathiassen G. & Økland R.H. (2007): Relative importance of host tree species and environmental gradients for epiphytic species composition, exemplified byPyrenomycetes s.lat. (Ascomycota) onSalix in Central North Scandinavia.Ecography 30: in press.

  • McCullagh P. &Nelder J.A. (1989):Generalized linear models, Ed. 2. Chapman & Hall, London.

    Google Scholar 

  • McCulloch C.E. &Searle S.R. (2002):Generalized, linear, and mixed models. Wiley, New York.

    Google Scholar 

  • Minchin P.R. (1987): An evaluation of the relative robustness of techniques for ecological ordination.Vegetatio 69: 89–107.

    Article  Google Scholar 

  • Murray B.G.J. (2000): Universal laws and predictive theory in ecology and evolution.Oikos 89: 403–408.

    Article  Google Scholar 

  • Murray B.G.J. (2001): Are ecological and evolutionary theories scientific?Biol. Rev. 76: 255–289.

    Article  PubMed  Google Scholar 

  • Nekola J.C. &White P.S. (1999): The distance decay of similarity in biogeography and ecology.J. Biogeogr. 26: 867–878.

    Article  Google Scholar 

  • Nordhagen R. (1943): Sikilsdalen og Norges fjellbeiter.Bergens Mus. Skr. 22: 1–607.

    Google Scholar 

  • Noss R.F. (1996): The naturalists are dying off.Conservation Biol. 10: 1–3.

    Article  Google Scholar 

  • Ohlson M., Økland R.H., Nordbakken J.-F. &Dahlberg B. (2001): Fatal interactions between Scots pine and Sphagnum mosses in bog ecosystems.Oikos 94: 425–432.

    Article  Google Scholar 

  • Økland R.H. (1986): Rescaling of ecological gradients. II. The effect of scale on symmetry of species response curves.Nord. J. Bot. 6: 661–670.

    Google Scholar 

  • Økland R.H. (1989): A phytoecological study of the mire Northern Kisselbergmosen, SE Norway. I. Introduction, flora, vegetation and ecological conditions.Sommerfeltia 8: 1–172.

    Google Scholar 

  • Økland R.H. (1990a): Vegetation ecology: theory, methods and applications with reference to Fennoscandia.Sommerfeltia Suppl. 1: 1–233.

    Google Scholar 

  • Økland R.H. (1990b): A phytoecological study of the mire Northern Kisselbergmosen, Rødenes, SE Norway. II. Identification of gradients by detrended (canonical) correspondence analysis.Nord. J. Bot. 10: 79–108.

    Article  Google Scholar 

  • Økland R.H. (1996): Are ordination and constrained ordination alternative or complementary strategies in general ecological studies?J. Veg. Sci. 7: 289–292.

    Article  Google Scholar 

  • Økland R.H. (1999): On the variation explained by ordination and constrained ordination axes.J. Veg. Sci. 10: 131–136.

    Article  Google Scholar 

  • Økland R.H. &Eilertsen O. (1993): Vegetation-environment relationships of boreal coniferous forests in the Solhomfjell area, Gjerstad, S Norway.Sommerfeltia 16: 1–254.

    Google Scholar 

  • Økland R.H., Økland T. &Rydgren K. (2001): Vegetation-environment relationships of boreal spruce swamp forests in Østmarka Nature Reserve, SE Norway.Sommerfeltia 29: 1–190.

    Google Scholar 

  • Økland R.H., Rydgren K. &Økland T. (1999): Single-tree influence on understorey vegetation in a Norwegian boreal spruce forest.Oikos 87: 488–498.

    Article  Google Scholar 

  • Økland R.H., Rydgren K. &Økland T. (2003): Plant species composition of boreal spruce swamp forests: closed doors and windows of opportunity.Ecology 84: 1909–1919.

    Article  Google Scholar 

  • Økland T. (1988): An ecological approach to the investigation of a beech forest in Vestfold, SE Norway.Nord. J. Bot. 8: 375–407.

    Article  Google Scholar 

  • Økland T. (1996): Vegetation-environment relationships of boreal spruce forest in ten monitoring reference areas in Norway.Sommerfeltia 22: 1–349.

    Google Scholar 

  • Økland T., Rydgren K., Økland R.H., Storaunet K.O. &Rolstad J. (2003): Variation in environmental conditions, understorey species richness, abundance and composition among natural and managedPicea abies forest stands.Forest Ecol. Managem. 177: 17–37.

    Article  Google Scholar 

  • Oksanen L. (2001): Logic of experiments in ecology: is pseudoreplication a pseudoissue?Oikos 94: 27–38.

    Article  Google Scholar 

  • Oksanen L. (2004): The devil lies in details: reply to Hurlbert.Oikos 104: 598–605.

    Article  Google Scholar 

  • Palmer M.W. (1988): Fractal geometry: a tool for describing spatial patterns of plant communities.Vegetatio 75: 91–102.

    Article  Google Scholar 

  • Peters R.H. (1991):A critique for ecology. Cambridge University Press, Cambridge.

    Google Scholar 

  • Pinheiro J.C. &Bates D.M. (2000):Mixed-effects models in S and S-PLUS. Springer, New York.

    Google Scholar 

  • Popper K.R. (1989):Conjectures and refutations: the growth of scientific knowledge. Routledge, London.

    Google Scholar 

  • Pukkala T., Kuuluvainen T. &Stenberg P. (1993): Below-canopy distribution of photosynthetically active radiation and its relation to seedling growth in a borealPinus sylvestris stand. A simulation approach.Scand. J. Forest Res. 8: 313–325.

    Google Scholar 

  • Rossi R.E., Mulla D.J., Journel A.G. &Franz E.H. (1992): Geostatistical tools for modeling and interpreting ecological spatial dependence.Ecol. Monogr. 62: 277–314.

    Article  Google Scholar 

  • Rydgren K., Økland R.H. &Økland T. (2003): Species response curves along environmental gradients. A case study from SE Norwegian swamp forests.J. Veg. Sci. 14: 869–880.

    Article  Google Scholar 

  • Sjörs H. (1948): Myrvegetation i Bergslagen (Mire vegetation in Bergslagen).Acta Phytogeogr. Suec. 21: 1–299.

    Google Scholar 

  • Skrindo A. &Økland R.H. (1998): Fertilization effects and vegetation-environment relationships in a boreal pine forest in Åmli, S Norway.Sommerfeltia 25: 1–90.

    Google Scholar 

  • Söderqvist T. (1986):The ecologists: from merry naturalists to saviours of the nation: a sociologically informed narrative survey of the ecologization of Sweden 1895–1975. Almqvist & Wiksell, Stockholm.

    Google Scholar 

  • Sokal R.R. &Rohlf F.J. (1995):Biometry, Ed. 3. Freeman, New York.

    Google Scholar 

  • Stewart-Oaten A. (1995): Rules and judgments in statistics: three examples.Ecology 76: 2001–2009.

    Article  Google Scholar 

  • ter Braak C.J.F. &Looman C.W.N. (1986): Weighted averaging, logistic regression and the Gaussian response model.Vegetatio 65: 3–11.

    Article  Google Scholar 

  • Trass H. &Malmer N. (1978): North European approaches to classification. In:Whittaker R.H. (ed.),Classification of plant communities, Junk, The Hague, pp. 201–245.

    Google Scholar 

  • Tuomikoski R. (1942): Untersuchungen über die Untervegetation der Bruchmoore in Ostfinnland I. Zur Methodik der pflanzensoziologischen Systematik.Ann. Bot. Soc. Zool.-Bot. Fenn. Vanamo 17: 1–203.

    Google Scholar 

  • Venables W.N. &Ripley B.D. (2002):Modern applied statistics with S. Springer, New York.

    Google Scholar 

  • Weber T.P. (1999): A plea for a diversity of scientific styles in ecology.Oikos 84: 526–529.

    Article  Google Scholar 

  • Whittaker R.H. (1962): Classification of natural communities.Bot. Rev. 28: 1–239.

    Article  Google Scholar 

  • Whittaker R.H. (1967): Gradient analysis of vegetation.Biol. Rev. Cambridge Philos. Soc. 42: 207–264.

    Article  PubMed  CAS  Google Scholar 

  • Wiens J.A. (1989): Spatial scaling in ecology.Funct. Ecol. 3: 385–397.

    Article  Google Scholar 

  • Wilson J.B. (2003): The deductive method in community ecology.Oikos 101: 216–218.

    Article  Google Scholar 

  • Wood S.N. (2006):Generalized additive models. Chapman & Hall, London.

    Google Scholar 

  • Yee T. W. (2006): Constrained additive ordination.Ecology 87: 203–213.

    Article  PubMed  Google Scholar 

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Correspondence to Rune Halvorsen Økland.

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Økland, R.H. Wise use of statistical tools in ecological field studies. Folia Geobot 42, 123–140 (2007). https://doi.org/10.1007/BF02893879

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