Classification and ordination of plant communities along an altitudinal gradient on the Presidential...

Plant Ecology 148: 81–103, 2000.© 2000Kluwer Academic Publishers. Printed in the Netherlands.

81

Classification and ordination of plant communities along an altitudinalgradient on the Presidential Range, New Hampshire, USA

Santiago SardineroInstituto Nacional de Investigaciones Agrarias (INIA), Centro de Investigaci´on Forestal (CIFOR), carretera de LaCoruña km 7, E-28040 Madrid, Spain. (e-mail: [email protected])

Received 11 December 1998; accepted in revised form 9 December 1999

Key words: Alpine tundra, Bioclimatology, Krummholz vegetation, New England, Northern Hardwoods,Spruce-Fir Forests, White Mountains

Abstract

An analysis of vegetation along an altitudinal gradient on the Presidential Range, New Hampshire, USA, usingthe Braun–Blanquet approach followed by multivariate data analysis is presented. Twelve main plant communitieshave been distinguished. Floristic information is presented in twelve tables and one appendix. The relationshipsof the communities to complex environmental gradients are analyzed using Correspondence Analysis. Floristiccomposition and community structure are controlled primarily by the altitudinal gradient (temperature, precipita-tion), and by mesotopographic conditions (snow accumulation, exposure and cryoturbation, slope position, andsoil moisture).

Abbreviations:CLC – complete linkage clustering, MNVAR – minimization of variance in new clusters, MISSQ– minimization of the increase of error sum of squares, SAHN – sequential, agglomerative, hierarchical and non-overlapping clustering techniques, CA – correspondence analysis, ss – saplings and seedlings, kr – krummholz.

Nomenclature:Gleason & Cronquist (1991) for vascular plants, except forBetula cordifoliaRegel,Coptis groenlandica(Oeder)Fernald, Empetrum nigrumssp. hermaphroditum(Lange ex Hagerup) Böcher,Huperzia selagossp. arctica(Grossh. ex Tolm.) Sipliv.,Minuartia groenlandica(Retz) Ostenfeld, Scirpus caespitosusvar. callosusBigelowex Torr.,Vaccinium vitis-idaeassp.minus(G. Llodd.) Hult́en. Nomenclature for lichens follows Esslinger & Egan(1995).

Introduction

The Presidential Range (New Hampshire, USA; Fig-ure 1) is a classical locality, frequently visitedby botanists and plant ecologists since the earliernineteenth-century, including Antevs (1932), Bald-win, Bigelow, Bliss (1963), Booth, Cutler, Griggs,Monahan, Oakes, Peck, Robbins, Thoreau, and Tuck-erman, among many others. Fenneman (1938) in-cluded the Presidential Range in the AppalachianHighlands, New England Province, White MountainsSection. Braun (1950) included it in the Hemlock-White Pine-Northern Hardwoods Region, New Eng-

land Section. Rivas-Martínez et al. (1999) included itin the North American Atlantic Region, AppalachianProvince, Appalachian Sector, North AppalachianSubsector. Küchler (1964) identified the northernhardwoods(Acer-Betula-Fagus-Tsuga),the northernhardwoods-spruce forest(Acer-Betula-Fagus-Picea-Tsuga), and the northeastern spruce-fir forest(Picea-Abies)as the potential natural vegetation within theterritory (see also modified version from U.S. Dep.Agric. 1978, and Barnes 1991). Greller (1988) iden-tified two major deciduous forests within this area:hemlock-white pine-northern hardwoods, and spruce-northern hardwoods. Bliss (1963) presented quantita-

82

tive data on the principal alpine plant communities andtheir ecological relationships with soils and meteoro-logical factors. In this paper we present a classificationand ordination analysis of the vegetation along analtitudinal gradient on the Presidential Range accord-ing to the Braun-Blanquet approach (Braun-Blanquet1964; Mueller-Dombois & Ellenberg 1974; Westhoff& van der Maarel 1978; Géhu & Rivas-Martínez 1981;Rivas-Martínez 1987), followed by multivariate dataanalysis. Our purpose is to develop a comprehen-sive, floristically based, vegetation classification inthe study area. The Presidential Range constitutes theterritory with largest alpine belt in the northern Ap-palachians. For this reason, it is the best place todevelop a basic vegetation model which could be ex-tended along the mountains of northeastern US withalpine summits: Presidential Range, Mts. Lafayetteand Lincoln on Franconia Ridge (NH), Mt. Mans-field and Camel’s Hump in the Green Mountains(VT), Katahdin (ME), and Adirondacks (NY; Fig-ure 1). This classification might be used as a basisfor the development of syntaxonomic vegetation unitsin northern Appalachians, in vegetation mapping, andin climatic change studies. Furthermore, it would bepossible to compare these plant communities to othertemperate, arctic, and alpine communities along theNorthern Hemisphere: Alaska (Walker et al. 1994),Eastern North America (Bergeron et al. 1984; Grandt-ner 1989–90; Miyawaki et al. 1994), Europe (Mucina1997), Greenland (Daniëls 1982, 1994), North Japan(Miyawaki 1988; Nakamura & Grandtner 1994; Naka-mura et al. 1994), etc., and to better understandingtheir global composition and distribution.

Study area

The Presidential Range comprises the highest peaks inthe northern Appalachians, which along with the Fran-conia Range to the west, contain the highest peaks inthe White Mountains. These mountains are composedof Lower Devonian mica schists and gneises of the Lit-tleton Formation, intruded by small dikes of quartzite.Glaciers eroded these mountains, leaving cirques, U-shaped valleys, glacial grooves in the rocks, erraticboulders, etc. (Billings et al. 1946).

The climate

Davis (1976; 1981) has documented multiple glacial-interglacial cycles within the 2 million-years of Pleis-

tocene time, possibly as many as sixteen, with an aver-age of 125 000 years for the complete cycle. Relativelyshort interglacial periods of 10 000 to 20 000 yearswere followed by long glacial periods up to 80 000 to100 000 years. The Pleistocene glaciers reached theirlast maximum extension about 18 000–20000 yearsago during the late Wisconsinan glaciation, and retreatbegan about 16 500 years ago (Delcourt & Delcourt1979). The Holocene, the present warm climatic inter-val, began 10 000 years ago and reached a temperaturemaximum 5 000 to 8 000 years ago (Mitchell 1977;Houghton et al. 1996). Present conditions appear torepresent those near the end of a typical interglacial in-terval (Mitchell 1977). Meanwhile the Earth seems tobe involved in a process of global warming, speciallythe Northern Hemisphere (Mann et al. 1998, 1999),correlated with a substantial and sustained rice in thecarbon dioxide atmospheric concentration over the lasttwo centuries (Keeling & Whorf 1998; Etheridge et al.1998).

Present climatic data were obtained for two me-teorological stations within the study area (NationalOceanic and Atmospheric Administration, NOAA), atthe top of Mt. Washington (Figure 2b), and at PinkhamNotch (Figure 2c). The increments of the mean an-nual temperature, and mean annual precipitation are−0.57 ◦C/100 m, and 63.27 mm/100 m, respectively,assuming a regular increment for them along the al-titudinal gradient. Bioclimatic nomenclature followsWalter & Lieth (1960–1967), Walter (1985), Rivas-Martínez (1997) and Rivas-Martínez et al. (1999).

Methods

Field sampling

The study was based on a data matrix composed of183 samples and 93 taxa. The sampling was doneduring 1995 and 1996, using the centralized replicatesampling procedure (Mueller-Dombois & Ellenberg1974). Plot locations were subjectively chosen be-tween the two meteorological stations, in areas ofhomogeneous vegetation, according to plant-formsand physiognomic-ecological plant formations (Rübel1930; Raunkiaer 1937; Braun-Blanquet 1964; Ellen-berg & Mueller-Dombois 1967a,b; Whittaker 1975;Box 1981; see Appendix 1). The moss layer was notrecorded.

83

Figure 1. Location map of the Presidential Range showing also other locations having alpine summits in the northern Appalachians.

Data analysis

The characterization of homogeneous plant commu-nities is one of the principal aims in phytosociol-ogy, phytogeography, phytoclimatologyand landscapeecology (see Legendre 1990). Clustering methodsrepresent a useful approach to this problem.

Syntaxonomic table sorting (Braun-Blanquet 1964;Mueller-Dombois & Ellenberg 1974; Westhoff & vander Maarel 1978) was used to detect and characterizepreliminary vegetation types in the data matrix with183 samples and 93 taxa. The abundance/dominancevalues of the 6-grade scale of Braun–Blanquet in thiscompiled raw table were transformed into a 0–9 ordi-

nal scale according to van der Maarel (1979). SeveralSequential, Agglomerative, Hierarchical and Non-overlapping clustering techniques (SAHN techniques;Sneath & Sokal 1973; Podani 1989a) were performedin order to classify the data. Similarity ratio, chorddistance, and euclidean distance were adopted to com-pute the distance between every pair of samples inthe resemblance matrix. Distance-optimizing cluster-ing methods like Complete Linkage clustering (CL),as well as homogeneity-optimizing clustering meth-ods like Minimum Variance of newly formed clusters(MNVAR), and Minimum Increase of Error Sum ofSquares (MISSQ), were carried out with the programsNCLAS and HMCL (Podani 1993, 1994). Then the

85

alternative results were compared looking for similar-ities in the composition of clusters, so we could have agood reason to assume that there is some real tendencyin the data towards grouping (Podani & Dickinson1984; Podani 1989b, 1994).

Ordination analyses were performed by Corre-spondence Analysis (CA), carried out with the pro-gram PRINCOMP (Podani 1993, 1994). The unitsdefined by cluster analysis were superimposed onthe ordination diagrams in order to provide a morecomplete analysis of the grouping, and to analyze re-lationships between vegetation and flora in terms ofunimodal response models (ter Braak 1985), by draw-ing sample plots and taxa plots. A good explanationon the interpretation of CA biplots may be found in terBraak (1995).

Since very different life forms, plant formations,and sample plot sizes were involved in the data analy-sis, a progressive dimensionality reduction was carriedout, splitting the data in data subsets with the help ofclassification and ordination results. Further analysesof the data subsets structure were carried out by com-parison of alternative clustering algorithms and CAordinations (Podani 1994).

For a final result, computer program ELLIPSE (Po-dani 1993, 1994) superimposed classification resultson ordination diagrams by drawing ellipses of equalconcentration around the centroids of clusters (Mardiaet al. 1979; Lagonegro & Feoli 1985) at 95% proba-bility level. The mean and standard deviation of eachordination dimension for every community were cal-culated. Differences between means among the twelvecommunities were tested by Student’st-test, giving theprobabilities that the null hypothesis is true, i.e., theprobabilities among every pair of plant communitiesof being the same community.

Results and discussion

Preliminary classification

The samples were sorted according to similarity ra-tio and CL (Figure 3a) which have been demonstratedto be effective algorithms in syntaxonomical studies(Mucina & van der Maarel 1989). Plant communitiesin this dendrogram correspond to those in Appen-dix 2. Classification using chord distance and MNVAR(Figure 3b) have also been demonstrated to be usefulalgorithms in syntaxonomical studies (Mucina & vander Maarel 1989), yielding the same composition of

plant communities, and giving good reason to assumethat there is some real tendency in the data towardsgrouping. Nevertheless, several differences can be ob-served between both clustering methods: Figure 3aseparates groups 5a and 5b at the highest dendrogramlevel, emphasizing their floristic differences, whereasFigure 3b gathers both groups in thePicea mariana–Abies balsameakrummholz vegetation, following aphysiognomic criterion. This last criterion has beenfollowed in this paper. Also, Figure 3a gathers groups10, 11, and 12, whereas group D in Figure 3b gath-ers groups 8–12 in the same branch; groups 8, 9,and 11 are located in one side, and groups 10 and12 in the other side. Figure 3b suggested two maingroups, the first one comprising the forests (group Ain Figure 3), and the second one comprising dwarftrees (krummholz) and alpine vegetation (group B inFigure 3). Classification using euclidean distance andMISSQ (dendrogram not shown) suggested the sametwo main groups (A and B), and also the same twelveplant communities.

Preliminary ordination

The results obtained by preliminary classification wereconfirmed by the ordination analyses, and we distin-guished the same two main groups (A and B) alongthe first CA axis, and groups C and D along thesecond axis (Figure 3c); plant community numberscorrespond to those in Appendix 2. A dimensionalityreduction was carried out, splitting the original datamatrix into two data matrices, one of them comprisingthe forests data (group A), and the other one com-prising the krummholz and alpine vegetation (groupB).

Forests data matrix classification

Two additional clustering algorithms were tested withthe forest samples, euclidean distance and MISSQ(Figure 4a), and chord distance and CL (Figure 4b).The plant communities yielded by these methods werethe same that those obtained in Figures 3b and 3a.Euclidean distance and MISSQ (Figure 4a) providedan easy interpretation of the forests data, so they weresorted according to this clustering method. Thus, fourmain forest types were distinguished (Tables 1–4).

Fagus grandifolia–Acer saccharum communityTable 1: samples 1–16, Group 1 in Figure 4Upper-montane northern hardwood forest.Fagusgrandifoliacombines withAcer saccharum, Acer pen-

86

Figure 3. Preliminary analysis. (a) Clustering using similarity ratio and CL. (b) Clustering using chord distance and MNVAR. (c) CA ordinationfor samples. (d) CA ordination for taxa. Vegetation types: (A) Forests. (B) Krummholz and alpine vegetation. (C) Upper-subalpine krummholz,and alpine dwarf shrub ericaceous vegetation. (D) Remaining alpine vegetation. Plant community numbers correspond to those of the twelvetables and Appendix 2.

sylvanicum, Betula alleghaniensis, Acer rubrum, Be-tula cordifolia, and Acer spicatumin the tree layer.Acer spicatum, Acer rubrum, Acer pensylvanicum,Acer saccharum, Betula alleghaniensis, Fagus gran-difolia, Viburnum alnifolium, Abies balsamea, Sor-bus americana, Picea rubens, Tsuga canadensisoc-cur in the subtree layers.Abies balsamea, Picearubens, andTsuga canadensisoccur in the tree layerwith low cover. Oxalis montana, Dryopteris campy-loptera, Maianthemum canadense, Trientalis borealis,Aralia nudicaulis, Clintonia borealis, Lycopodiumannotinum, Cypripedium acaule, Thelypteris phe-gopteris, Trillium undulatum, Medeola virginiana,Viola selkirkii, Uvularia sessilifolia,and Smilacinaracemosaoccur in the herb layer.

Two variants can be detected:Betula alleghaniensis–Acer rubrum–Acer pensylvanicumdominated stands

(Group 1a in Figure 4, and in Table 1), andAcer saccharum–Fagus grandifoliadominated stands(Group 1b in Figure 4, and in Table 1), where the latterover time seems to replace the former, according to themodels shown by Pacala et al. (1996).

This forest is replaced byAbies balsamea–Betulaalleghaniensiscommunity (number 3) on xeric soils(see Figure 8).

This community bears close resemblance toBetuloalleghaniensis–Aceretum sacchariiGrandtner 1989–1990, andOxalis montana–Dryopteris campyloptera–Fagus grandifoliacommunity Okuda 1994.

Betula cordifolia–Sorbus americana communityTable 2: samples 17–24, Group 2 in Figure 4(Montane)-subalpine softwood forest whereBetulacordifolia and Sorbus americanadominate the tree

87

Figure 4. Analysis of the forests data matrix. (a) Clustering using euclidean distance and MISSQ. (b) Clustering using chord distance andCL. (c) CA ordination for samples. (d) CA ordination for taxa. Plant communities: (1)Fagus grandifolia–Acer saccharum(1a. var. dominatedby Betula alleghaniensis. 1b. var. dominated byFagus grandifoliaandAcer saccharum. (2) Betula cordifolia–Sorbus americana.(3) Abiesbalsamea–Betula alleghaniensis. (4) Abies balsamea–Betula cordifolia(4a. var. with more abundance ofDryopteris campyloptera, Cornuscanadensis, Trientalis borealis, Clintonia borealis, andLycopodium annotinum. 4b. var. with more abundance ofPicea rubens).

layer, occurring withAbies balsameaand Betulaalleghaniensis. Abies balsamea, Sorbus americana,Acer spicatum, Sambucus canadensis, Viburnum al-nifolium, Picea rubens,and Acer pensylvanicumoccur in the subtree layers.Oxalis montana, Dry-opteris campyloptera, Aster acuminatus, Maianthe-mum canadense, Trientalis borealis,andAralia nudi-caulis occur in the herb layer. Since it is a soft-wood and rapid-growth community, it seems to bethe secondary forest ofAbies balsamea–Betula cordi-folia community (Table 4), and theAbies balsamea–Betula alleghaniensiscommunity (Table 3) whichgrows close to the montane–subalpine boundary (Fig-ure 8). This community has been described accordingto the Code of Phytosociological Nomenclature (CNP,

Barkman et al. 1986) asSorbo americanae–BetuletumcordifoliaeSardinero in Rivas-Martínez et al. (1999).

Abies balsamea–Betula alleghaniensis communityTable 3: samples 25–35, Group 3 in Figure 4Upper-montane-(subalpine) spruce-fir forest domi-nated byAbies balsameaand Picea rubens, com-bined with Betula cordifolia, Betula alleghaniensis,Acer pensylvanicum, Acer rubrum, Acer saccharum,Fagus grandifolia, Tsuga canadensis,and Sorbusamericana. This forest grows on xeric soils, belowAbies balsamea–Betula cordifoliacommunity. To-wards deeper soils it contacts withFagus grandifolia–Acer saccharumcommunity (Figure 8). Structurally, itis anAbies balsamea–Picea rubensdominated forest,but floristically it has some transgressive species fromthe deciduous forests such asBetula alleghaniensis,

88

Table 1. Fagus grandifolia–Acer saccharumcommunity (1a.var. dominated byBetula alleghaniensis.1b. var. domi-nated by Fagus grandifolia and Acer saccharum).Refer-ence no.: 001. Pinkham Notch, Tuckerman Ravine Trail,09/14/95/01. 002. Tuckerman Ravine Trail, 06/14/95/02. 003.Gulf of Slides, 09/27/96/08. 004. Tuckerman Ravine Trail,06/14/95/03. 005. Gulf of Slides, 09/27/96/05. 006. John Sher-burne Ski Trial, 09/28/96/01. 007, 008, 009, 010. Old JacksonRoad, 09/28/96/08,06,05,09. 011. Tuckerman Ravine Trail,09/14/95/03. 012. Gulf of Slides Ski Trail, 09/27/96/03. 013,014. Old Jackson Road, 09/28/96/02,04. 015, 016. Gulf ofSlides Ski Trail, 09/27/96/01,02.

Plant community No. 000000 0000000000

111111 1111111111

Plant community variant aaaaaa bbbbbbbbbb

Relev́e No. 000000 0000000000

000000 0001111111

123456 7890123456

Altitude (x 10 m) 000000 0000000000

667666 7668766666

573972 8750062425

Slope (x 10%) 000300 3002300000

Area (x 100 square m) 242522 2222222232

Faithful and differential taxa:Acer saccharum 1+12+2 4545433331Fagus grandifolia 1.1111 2132343445Acer saccharumss 1121+3 2233222231Fagus grandifoliass .+1.+. 2231222232Viola selkirkii ...1.+ .1211.+..1

Uvularia sessilifolia .2.... +.1+1...1.

Cypripedium acaule 1..1+. ....1...1+

Smilacina racemosa .1+... .+1.....++

Sambucus pubens ...+.+ .+....+++.

Carex grayii .1.1.1 ...1....+.

Medeola virginiana ...1.+ .1....+.11

Brachyelytrum erectum .....1 1.11....1.

Constants:Betula alleghaniensis 243345 2211133211

Acer rubrum 421111 .l+..++1.+

Acer rubrumss 222221 ....2+11+1

Acer pensylvanicum 1212+. ....1...12

Viburnum alnifolium 322211 2322333333

Aralia nudicaulis 221233 +211212111

Acer pensylvanicumss 222121 22213122..

Clintonia borealis 231212 1221222122

Maianthemum canadense 232222 2211113122

Dryopteris campyloptera 322222 3222323122

Abies balsamea 12.22+ 1.12++++1+

Abies balsameass 11+111 11..1+++11

Betula cordifolia 1+2121 11.+1++.1+

Picea rubensss ++.+1. 1.+11+.++1

Acer spicatumss 22.212 1+..2.2211

Oxalis montana 3332.+ +...333133

Trientalis borealis 12.111 11..111.11

Betula alleghaniensisss .1.112 ++++1..+1.

Table 1. Continued

Sorbus americanass 21111+ .++.1.1...

Lycopodium annotinum 31.... ...3321112

Trillium undulatum .1+.++ .+..++....

Other taxa:Thelypteris phegopteris ..+2+1 ..1.1...+.

Picea rubens 12.11. ....++....

Aster acuminatus ....11 ...1.1....

Monotropa uniflora ...... ...+..+.++

Acer spicatum .1.1.. .....2....

Carex arctata ...+.+ ......+...

Amelanchier bartramiana ...+.. ..+......+

Mitchella repens ....+. ...1.....+

Fragaria virginiana .....1 ...+....1.

Additional taxa with one or two occurrences: Tsuga canadensisss: 1 in rel. 1, and + in rel. 2.Polygonatum biflorum:+ in rels. 5and 15.Prunus serotina:1 in rel. 6, and + in rel. 15.Thalictrumpolygamum:+ in rels. 6 and 15.Thelypteris noveboracensis:+ inrels. 7 and 12.Cornus canadensis:+ in rels. 13 and 16.Arisaematriphyllum: + in rels. 13 and 16.Tsuga canadensis:1 in rel. 1.Sorbus americana:1 in rel. 4. Betula cordifolia ss: 1 in rel. 6.Lycopodium obscurum:1 in rel. 9.Cornus alternifolia: + in rel. 11.

Acer pensylvanicum, Acer rubrum, Acer saccharum,Fagus grandifolia, Tsuga canadensis, Viburnum al-nifolium, Aralia nudicaulis, Trillium undulatum,andCypripedium acaule. The tree species of this trans-gressive flora never dominate the tree-layer.

This community bears close resemblance toBe-tulo alleghaniensis–Abietetum balsameaeGrandtner1989–1990.

Abies balsamea–Betula cordifolia community.Table 4: samples 36–56, Group 4 in Figure 4Subalpine balsam fir forest whereAbies balsameadominates the tree layer, accompanied byBetulacordifolia and Picea rubens. The presence ofPicearubens is lower than inAbies balsamea–Betula al-leghaniensiscommunity. Abies balsamea, Sorbusamericana, Betula cordifolia, and Picea rubensoc-cur in the subtree layers.Oxalis montana, Dryopteriscampyloptera, Maianthemum canadense, Trientalisborealis, Cornus canadensis, Coptis groenlandica, Ly-copodium annotinumandClintonia borealisoccur inthe herb layer.

This community bears close resemblance toAbietibalsameae-Piceetum rubentisMarcotte & Grandtner1974, andBetulo papyriferae–Abietetum balsameaeGrandtner 1989–1990.

89

Table 2. Betula cordifolia–Sorbus americanacommunity.Ref-erence no.: 017. Old Jackson Road, 09/28/96/07. 018. BoottSpur Trail, 09/30/96/04. 019, 020, 021, 022. John SherburneSki Trail, 09/15/95/05,01,04,02. 023, 024. Lion Head Trail,10/02/96/08,09.

Plant community No. 00000000

22222222

Plant community variant --------

Relev́e No. 00000000

11122222

78901234

Altitude (x 10 m) 00101011

78091922

40000305

Slope (x 10%) 00444400

Area (x 100 square m) 22212122

Faithful and differential taxa:Betula cordifolia 54534344Sorbus americanass 22221222Acer spicatumss 2123222+Sorbus americana .2.33323Aster acuminatus 11211.22

Sambucus canadensis +++.+1..

Constants:Abies balsameass 23323332Dryopteris campyloptera 22333332

Viburnum alnifolium 2.+11221

Trientalis borealis 111111.+

Abies balsamea 2212+...

Oxalis montana .22221..

Picea rubensss 12++...+

Betula alleghaniensis 1122.2..

Maianthemum canadense 1.1113..

Aralia nudicaulis 1.1+.+.+

Other taxa:Betula cordifoliass 1....+22

Prunus serotina +1....+1

Acer pensylvanicumss +..1.1..

Dennstaedtia punctilobula .+....21

Cornus canadensis ....12.2

Clintonia borealis .....212

Additional taxa with one or two occurrences: Betulaalleghaniensisss: 1 in rels. 17 and 22.Trillium undulatum:+ in rels. 18 and 23.Carex arctata: 1 in rels. 23 and 24.Brachyelytrum erectum:1 in rel. 17.Cornus alternifolia: + inrel. 17.Sambucus pubens:+ in rel. 17.Viola selkirkii: + in rel.17. Acer saccharumss: + in rel. 17.Acer saccharum:+ in rel17. Picea rubens:+ in rel. 18.Lycopodium annotinum:2 in rel.22. Fragaria virginiana: 1 in rel. 23.Thelypteris phegopteris:1in rel. 23.Amelanchier bartramiana:2 in rel. 24.

Table 3. Abies balsamea–Betula alleghaniensiscommunity.Ref-erence no.:025. Dolly Copp Road, 09/29/96/03. 026, 027. BoottSpur Trail, 09/30/96/02,03. 028. Gulf of Slides, 09/27/96/04.029. Boott Spur Trail, 09/30/96/01. 030. Old Jackson Road,09/28/96/03. 031. Tuckerman Ravine Trail, 06/14/95/04. 032.Pinkham Notch, Tuckerman Ravine Trail, 09/14/95/02. 033. Gulfof Slides, 09/27/96/07. 034. John Sherburne Ski Trail, 09/14/95/04.035. Gulf of Slides, 09/27/96/06.


33333333333

Plant community variant -----------

Relev́e No. 00000000000

22222333333

56789012345

Altitude (x 10 m) 00000000000

57865666787

06169385100

Slope (x 10%) 40404000000

Area (x 100 square m) 22222221222

Faithful and differential taxa:Abies balsamea 44442444353Picea rubens 22233232313Abies balsameass 23233332334Picea rubensss 33333322312Betula cordifolia 21222121222

Acer spicatumss 11+11111+2+

Acer pensylvanicumss 12+2111111+

Viburnum alnifolium 11+1.22211.

Aralia nudicaulis 11+.21.++11

Betula alleghaniensis .++1+++111.

Clintonia borealis 11..2221121

Sorbus americanass +11+..2112+

Acer rubrumss +1+1.111+++

Betula alleghaniensisss ++.1..+1++.

Acer rubrum +1.1+1.++..

Trillium undulatum .+.+1+2..++

Acer pensylvanicum +...+21++..

Constants:Dryopteris campyloptera 122.1311221

Maianthemum canadense 11..+3+22+1

Oxalis montana .11..211333

Trientalis borealis ++..1.11.11

Other taxa:

Aster acuminatus 11.+1.....+

Lycopodium annotinum 1+...2...11

Betula cordifoliass ....1.111..

Lycopodium obscurum 121........

Fagus grandifolia +..1.1.....

Acer saccharum +..1.+.....

Coptis groenlandica .1+.1......

90

Table 3. Continued

Dennstaedtia punctilobula .++......1.

Tsuga canadensis ....2.11...

Cornus canadensis ........+++

Sorbus americana .1.......11

Additional taxa with one or two occurrences: Cypripediumacaule: + in rel. 25, and 1 in rel. 29.Fagus grandifoliass: 1in rel. 28, and + in rel. 30.Tsuga canadensisss: 2 in rels. 29 and32. Acer spicatum:1 in rel. 25.Monotropa uniflora:+ in rel. 25.Vaccinium angustifolium:+ in rel. 26.Smilacina racemosa:+ inrel. 31.

Forests data matrix ordination

The ordination diagrams obtained using CA (Fig-ures 4c, 4d) illustrate two main sources of variabil-ity. Axis 1 describes the altitudinal sequence, start-ing by Fagus grandifolia–Acer saccharumcommu-nity (group 1) at the right side, following byAbiesbalsamea–Betula alleghaniensiscommunity (group 3)in the middle, and finishing withAbies balsamea–Betula cordifolia community (group 4). Axis 2seems to be related to the successional process be-tween Betula cordifolia–Sorbus americanacommu-nity (group 2), and group 4 and the upper part ofgroup 3 (Figure 8); it also expresses internal variabilitywithin group 4.

Classification of krummholz and alpine vegetation

Classification using similarity ratio and MNVAR (Fig-ure 5a), euclidean distance and MISSQ (Figure 5b),and chord distance and MNVAR (group B in Fig-ure 3b), yielded the same composition of plant com-munities, showing that a solid data structure wasunderlying. All of these classifications suggested alsotwo main groups, the first one comprising the upper-subalpine krummholz and alpine dwarf shrub erica-ceous dominated vegetation (group C in Figures 3band 5), and the second one comprising the remainingalpine vegetation (group D in Figures 3b and 5).

Ordination of krummholz and alpine vegetation

The ordination diagrams obtained using CA (Fig-ures 5c, 5d) illustrate two main sources of variability.Axis 1 describes the altitudinal sequence, starting byPicea mariana–Abies balsameacommunity (group 5)at the right side, following byVaccinium uliginosum–Cetraria islandicacommunity (group 6) in the mid-dle, and finishing with groups 8, 9, 10, and 11at the left side. Axis 2 mainly isolatesEmpetrum

Table 4. Abies balsamea–Betula cordifoliacommunity (4a. var.with more abundance ofDryopteris campyloptera, Cornuscanadensis, Trientalis borealis, Clintonia borealis,andLycopodiumannotinum.4b. var. with more abundance ofPicea rubens).Ref-erence no.: 036. Mt. Washington Road, 06/14/95/05. 037. JohnSherburne Ski Trail, 09/15/95/06. 038, 039, 040, 041, 042.Boott Spur Trail, 09/30/96/10,11,12,14,05. 043. Lion Head Trail,10/02/96/06. 044. John Sherburne Ski Trail, 09/14/95/05. 045. BoottSpur Trail, 09/30/96/08. 046, 047, 048. John Sherburne Ski Trail,09/15/95/08,03,07. 049, 050. Lion Head Trail, 10/02/96/04,03.051. Tuckerman Ravine Trail, 10/02/96/02. 052. Lion HeadTrail, 10/02/96/05. 053. Tuckerman Ravine Trail, 10/02/96/01.054. Lion Head Trail, 10/02/96/07. 055, 056. Boott Spur Trail,09/30/96/07,09.

91

Figure 5. Analysis of krummholz and alpine vegetation. (a) Clustering using similarity ratio and MNVAR. (b) Clustering using euclideandistance and MISSQ. (c) CA ordination for samples. (d) CA ordination for taxa. Vegetation types: (C) Upper-subalpine krummholz, andalpine dwarf shrub ericaceous vegetation. (D) Remaining alpine vegetation. Plant community numbers correspond to those of Tables 5-12, andAppendix 2.

hermaphroditum–Vaccinium cespitosumcommunity(group 7), andDeschampsia flexuosa–Solidago cutlericommunity (group 12). This axis seems to be relatedto the snow cover gradient. Axis 1 also distinguishesgroups C and D obtained by clustering. For this rea-son, a new dimensionality reduction was carried outsplitting the data matrix into two data matrices. Thefirst one comprising the upper-subalpine krummholzand alpine dwarf shrub ericaceous dominated vegeta-tion (group C in Figures 3 and 5), and the second onecomprising the remaining alpine vegetation (group Din Figures 3 and 5).

Classification of krummholz and alpine dwarf shrubericaceous dominated vegetation

Classification using chord distance and MNVAR(Group C in Figure 3b), similarity ratio and MN-

VAR (Group C in Figure 5a), euclidean distanceand MISSQ (Group C in Figure 5b), euclidean dis-tance and CL (Figure 6a), and euclidean distanceand MNVAR (Figure 6b) yielded the same compo-sition of plant communities. Euclidean distance andCL (Figure 6a) provided an easy interpretation of thisdata set, so it was sorted according to this cluster-ing method. Thus, three main plant communities weredistinguished (Tables 5–7).

Picea mariana–Abies balsamea community. Table 5:samples 57–86, Group 5 in Figures 3, 5, and 6Upper-subalpine black spruce–balsam fir krummholzvegetation in which two main variants have beendistinguished:

– Closed krummholz constituted fundamentally byAbies balsameawith lower amounts ofPicea mari-ana. Plants such asCornus canadensis, Coptis groen-

92

Figure 6. Upper-subalpine krummholz, and alpine dwarf shrub ericaceous vegetation analysis. (a) Clustering using euclidean distance and CL.(b) Clustering using euclidean distance and MNVAR. (c) CA ordination for samples. (d) CA ordination for taxa. Plant communities: (5)Piceamariana–Abies balsamea. 5a. closed krummholz = var. withCornus canadensis. 5b. scattered krummholz = var. withVaccinium vitis-idaeassp.minus. (6) Vaccinium uliginosum–Cetraria islandica. 6a. var. withLedum groenlandicumandBetula cordifolia. 6b. var. withoutLedumgroenlandicumnor Betula cordifolia. (7) Empetrum hermaphroditum–Vaccinium cespitosum.

landica, Maianthemum canadense, Oxalis montana,andGaulteria hispidulamay be found inside of thisvegetation (group 5a in Figures 3, 5, and 6; Table 5,samples 57–65).

– Scattered krummholz, in whichAbies balsameahas progressively less significance at the same timethatPicea marianais increasing in abundance. The in-fluence of the alpine belt starts here with the presenceof Vaccinium vitis-idaea, Cetraria islandica, Clad-ina rangiferina, Juncus trifidus,andCarex bigelowii(group 5b in Figures 3, 5, and 6; Table 5, samples 66–86).

Vaccinium uliginosum–Cetraria islandica community.Table 6: samples 87–115, Group 6 in Figures 3, 5,and 6Lower-alpine dwarf shrub heath community domi-nated byEricaceae,basicallyVaccinium vitis-idaeaand Vaccinium uliginosum. Cetraria islandicaandCladina rangiferinaare the most important lichens,although other species such asCladonia pleurota, Ce-traria nivalis, Cladina stellaris,etc. also occur. Twovariants have been distinguished:

– dwarf shrub heath variant characterized by thepresence ofLedum groenlandicum, andBetula cordi-folia (Table 6: samples 87–101, Group 6a in Figures 3,5 and 6). This variant is typically located just above

93

Table 5. Picea mariana–Abies balsameacommunity (5a. closedkrummholz = var. withCornus canadensis. 5b. scattered krummholz= var. withVaccinium vitis-idaeasubsp. minus).Reference no.:57.Lion Head Trail, 09/13/95/02. 58, 59. John Sherburne Ski Trail,09/15/95/10,09. 60, 61, 62. Lion Head Trail, 10/02/96/35,36,28.63, 64, 65, Lion Head Trail, 09/18/95/38,37,39. 66. Davis Path,09/18/95/30. 67. Lion Head Trail, 09/13/95/01. 68. Lion HeadTrail, 10/02/96/22. 69. Davis Path, 09/18/95/28. 70, 71. Boott SpurTrail, 09/30/96/15,13. 72, 73. Lion Head Trail, 10/02/96/24,30. 74.Lion Head Trail, 09/18/95/04. 75. Lion Head Trail, 10/02/96/12.76. Lawn Cutoff, 09/18/95/33. 77, 78, 79, 80, 81, 82, 83, 84.Lion Head Trail, 10/02/96/11,10,14,18,16,20,26,32. 85. Davis Path,09/18/95/31. 86. Lion Head Trail, 09/18/95/02.

krummholz (Bliss 1963), at the beginning of the alpinebelt.

– dwarf shrub heath variant characterized by thehigher frequency ofRhododendron lapponicum, Di-apensia lapponica, Potentilla tridentata, andJuncustrifidus, and by the very low frequency ofLedumgroenlandicumand Betula cordifolia(Table 6: sam-

Table 6. Vaccinium uliginosum–Cetraria islandicacommunity (6a.var. with Ledum groenlandicumand Betula cordifolia. 6b. var.with Rhododendron lapponicum, Potentilla tridentata,andDiapen-sia lapponica). Reference no.: 87, 88, 89, 90, 91. Lion HeadTrail, 10/02/96/13,17,15,19,25. 92. Boot Spur Trail, 09/30/96/16.93. Lion Head Trail, 10/02/96/23. 94. Davis Path, 09/18/95/18. 95,96, 97. Lion Head Trail, 10/02/96/21,29,31. 98. Lion Head Trail09/13/95/08. 99. Lion Head Trail, 10/02/96/27. 100, 101. Lion HeadTrail, 09/13/95/03,04. 102. Mt. Washington east face 10/01/96/26.103, 104, 105. Mt. Washington, south face, 09/16/95/02,06,08.106, 107. Davis Path, 09/18/95/21,27. 108, 109. Mt. Washing-ton, south face, 09/16/95/04,09. 110. Between Alpine GardenTrail and Tuckerman Ravine Trail, 10/01/96/09. 111. Alpine Gar-den Trail, 10/01/96/12. 112. Lion Head Trail, 10/02/96/33. 113.Lion Head Trail, 09/18/95/03. 114. Between Alpine Garden Trailand Tuckerman Ravine Trail, 10/01/96/10. 115. The Cow Pasture,10/01/96/34.

ples 102-115, Group 6b in Figures 3, 5 and 6). Thisvariant is located just above variant 6a.

This community bears close resemblance toCe-traria cucullata–Vaccinium uliginosumcommunity(Nakamura & Grandtner 1994).

94

Table 7. Empetrum hermaphroditum–Vaccinium cespitosumcom-munity. Reference no.: 116. Mt. Washington south face,09/16/95/11. 117. Between Alpine Garden Trail and TuckermanRavine Trail, 10/01/96/11. 118. Lion Head Trail, 09/18/95/06.119. Mt. Washington, south face, 09/16/95/07. 120. Davis Path,09/18/95/29. 121. Lion Head Trail to Tuckerman Ravine Trail,09/18/95/07. 122. Tuckerman Crossover, 09/18/95/11.


7777777

Plant community variant -------

Relev́e No. 1111111

1111222

6789012

Altitude (x 10 m) 1111111

7758656

5152252

Slope (x 10%) 6436434

Area (square m) 0000000

0200000

6524444

Faithful and differential taxa:Empetrum hermaphroditum 3343324

Vaccinium cespitosum 2213143

Coptis groenlandica 2.1..1.

Lycopodium annotinum ..2.122

Cornus canadensis ..1..1.

Constants:Vaccinium uliginosum 323232.

Carex bigelowii 21.211.

Cetraria islandica 2..1221

Vaccinium vitis-idaeassp.minus 1..1.11

Juncus trifidus .+.2121

Additional taxa with one or two occurrences: Scirpus caespi-tosusvar. callosus:2 in rels. 116 and 117.Potentilla tridentata:1 in rels. 116 and 117.Ledum groenlandicum:+ in rels. 116 and119. Cladina rangiferina:1 in rel. 119, and 2 in rel. 122.Loise-leuria procumbens:1 in rel. 117.Sphagnumsp.: 1 in rel. 118.Deschampsia flexuosa:+ in rel. 121.

Empetrum hermaphroditum–Vaccinium cespitosumcommunity. Table 7: samples 116–122, Group 7 inFigures 3, 5 and 6Lower-alpine dwarf shrub heath dominated byEm-petrum hermaphroditum, Vaccinium cespitosumandVaccinium uliginosum.It is located on gentle slopesand little depressions, where there is larger snow ac-cumulation than inVaccinium uliginosum–Cetrariaislandicacommunity. Due to this higher moisture con-dition, Lycopodium annotinum, Coptis groenlandica,Cornus canadensis,andScirpus caespitosusvar. cal-losusalso occur here, and the frequency of lichensdecreases.

Table 8. Minuartia groenlandica–Agrostis mertensiicommunity.Reference no.: 123, 124, 125, 126, 127.Lion Head Trail,09/13/95/06,05,09,07,10. 128. Mt. Washington, east face, 10/01/96/25.129. Nelson Crag Trail, 10/01/96/02. 130. Lawn Cutoff, 09/18/95/32.131. Mt. Washington, east face, 10/01/96/24. 132. Mt Washington,south face, 09/16/95/01. 133. Davis Path, 09/18/95/20.


88888888888

Plant community variant -----------

Relev́e No. 11111111111

22222223333

34567890123

Altitude (x 10 m) 11111111111

54555875866

08204629762

Slope (x 10%) 52050000000


00000000000

22424641621

Faithful and differential taxa:Minuartia groenlandica 23333133323

Agrostis mertensii 323223213..

Juncus trifidus 332322+1.3.

Diapensia lapponica 22221.+....

Carex bigelowii .....+111++

Potentilla tridentata ......+....

Other taxa:Betula cordifoliakr 111........

Vaccinium uliginosum 11.........

Vaccinium vitis-idaeassp. minus 1.+.+......

Ledum groenlandicum 1..........

Huperzia selagossp. arctica ..+........

Carex capillaris .....1.....

Cetraria islandica .....1.....

Cetraria nivalis .........+.

Ordination of krummholz and alpine dwarf shrubericaceous dominated vegetation

The ordination diagrams obtained using CA (Fig-ures 6c, 6d) illustrate two main gradients. Axis 1describes the altitudinal sequence, starting by theclosed krummholz variety ofPicea mariana–Abiesbalsameacommunity (group 5a), located at the rightside, following with the scattered krummholz vari-ety of the same community (group 5b). Next comesVaccinium uliginosum–Cetraria islandicacommunityvar. withLedum groenlandicumandBetula cordifolia(group 6a), finishing with theVaccinium uliginosum–Cetraria islandica community var. withoutLedumgroenlandicumnor Betula cordifolia(group 6b), lo-

95

Figure 7. Analysis of the remaining alpine vegetation. (a) Clustering using similarity ratio and CL. (b) Clustering using chord distance andMNVAR. (c) CA ordination for samples. (d) CA ordination for taxa. Plant communities: (8)Minuartia groenlandica–Agrostis mertensii. (9) Di-apensia lapponica–Rhododendron lapponicum. (10)Carex bigelowii–Solidago cutleri. (11)Salix uva-ursi–Solidago cutleri. (12)Deschampsiaflexuosa–Solidago cutleri.

cated at the left side. Axis 2 mainly isolatesEmpetrumhermaphroditum–Vaccinium cespitosumcommunity(Group 7), due to its different floristic compositionsupported on larger snow accumulation.

Classification of the remaining alpine vegetation

Classification using chord distance and MNVAR(Group D in Figure 3b), similarity ratio and MN-VAR (Group D in Figure 5a), euclidean distance andMISSQ (Group D in Figure 5b), similarity ratio andCL (Figure 7a), and chord distance and MNVAR (Fig-ure 7b) yielded the same composition of plant commu-nities. Similarity ratio and CL (Figure 7a) provided aneasy interpretation of this vegetation, so it was sortedaccording to this clustering method. Thus, five mainplant communities were distinguished (Tables 8–12).

Minuartia groenlandica–Agrostis mertensiicommunity. Table 8: samples 123–133, Group 8 inFigures 3, 5 and 7Alpine community growing in rock cracks at the be-ginning of the alpine belt consisting ofMinuartiagroenlandica, Agrostis mertensii, Juncus trifidus,andDiapensia lapponica. Also can be located on moistersites, along alpine trails and other disturbed locations,as primary succession communities on sandy soils,characterized byMinuartia groenlandica, Agrostismertensii, Juncus trifidus, little amounts ofCarexbigelowii,and very low amounts ofDiapensia lappon-ica.

Data belonging to this community have been re-ported by Bergeron et al. (1984), and Nakamura &Grandtner (1994) from Mount du Lac des Cygnes.

96

Table 9. Diapensia lapponica–Rhododendron lapponicumcom-munity. Reference no.:134. Nelson Crag Trail, 10/01/96/05.135. Alpine Garden Trail, 10/01/96/21. 136. The Cow Pasture,10/01/96/17. 137, 138, 139. Davis Path, 09/18/95/25,24,17.140. Tuckerman Crossover, 09/18/95/14. 141. Lion HeadTrail, 10/02/96/34. 142. Davis Path, 09/18/95/26. 143. NelsonCrag Trail, 10/01/96/03. 144. The Cow Pasture, 10/01/96/13.145. Lion Head Trail, 09/18/95/01. 146, 147. Davis Path,09/18/95/22,23. 148. Tuckerman Crossover, 09/18/95/12. 149.Lawn Cutoff, 09/18/95/34. 150. Davis Path, 09/18/95/15.151. Tuckerman Crossover, 09/18/95/13. 152. Davis Path,09/18/95/16.


9999999999999999999

Plant community variant -------------------

Relev́e No. 1111111111111111111

3333334444444444555

4567890123456789012

Altitude (x 10 m) 1111111111111111111

7776666667756665666

1021133212221139333

Slope (x 10%) 0000000000000000000

Area (square m) 0000000000000000000

0000000000010000000

4962222422902222211

Faithful and differential taxa:Juncus trifidus 4342322221222222311

Diapensia lapponica 2..4434445434444334

Rhododendron lapponicum 1..21122212222112..

Loiseleuria procumbens 1...12222..11122.1.

Minuartia groenlandica 11+......++......2.

Agrostis mertensii .+2.1..+.+.2.......

Constants:Potentilla tridentata 22222211111122.....

Carex bigelowii .11112211211121...2

Other taxa:Vaccinium uliginosum ...2.+++.+.+12+.1..

Cetraria islandica 2321..++.....+.....

Vaccinium vitis-idaeassp. minus ........1..1+1.....

Solidago cutleri 1.+........1.......

Cladina rangiferina .1.1.........+.....

Cetraria nivalis ...1..+......+.....

Salix uva-ursi ...2...............

Ledum groenlandicum .....1.............

Huperzia selagossp. arctica ............+......

Table 10. Carex bigelowii–Solidago cutlericommunity.Ref-erence no.: 153. Ball Crag, 10/01/96/28. 154, 155, 156,157, 158. The Cow Pasture, 10/01/96/15,14,18,16,29. 159.Alpine Garden Trail, 10/01/96/08. 160. Tuckerman RavineTrail, 09/18/95/08. 161. Nelson Crag Trail, 10/01/96/07.162. Alpine Garden Trail, 10/01/96/06. 163. Ball Crag,10/01/96/27. 164. Mt. Washington, east face, 10/01/96/23.165, 166. Nelson Crag Trail, 10/01/96/04,01. 167. TheCow Pasture, 10/01/96/20. 168. Mt. Washington, south face,09/16/95/03. 169. Davis Path, 09/18/95/19.


00000000000000000

Plant community variant -----------------

Relev́e No. 11111111111111111

55555556666666666

34567890123456789

Altitude (x 10 m) 11111111111111111

77777776778877786

22222220324712022

Slope (x 10%) 00000000000000040

Area (square m) 00000000000000000

11111210102200020

52602004260068954

Faithful and differential taxa:Carex bigelowii 54454554555555555

Potentilla tridentata 222332221....1...

Solidago cutleri 2221.2+.+........

Constants:Minuartia groenlandica +....11.22112211.

Agrostis mertensii 21122...112......

Juncus trifidus .+.11.1.12....11.

Other taxa:Vaccinium uliginosum 1....1.1+........

Cetraria nivalis ..1.++...........

Diapensia lapponica .++..............

Cetraria islandica ..1.+............

Rhododendron lapponicum ..+...+..........

Stellaria borealis ..........+....l.

Vaccinium cespitosum ..1..............

Salix uva-ursi .....1...........

Geum peckii .......2.........

Sphagnumsp. .......2.........

Vaccinium vitis-idaeassp. minus .......1.........

Carex capillaris ..........+......

Poa glauca ...............+.

97

Table 11. Salix uva-ursi–Solidago cutlericommunity.Refer-ence no.: 170. The Cow Pasture, 10/01/96/30. 171. Nel-son Crag Trail, 10/01/96/31. 172. Alpine Garden Trail,10/01/96/32. 173, 174. The Cow Pasture, 10/01/96/33,22.


11111

Plant community variant -----

Relev́e No. 11111

77777

01234

Altitude (x 10 m) 11111

77777

22220

Slope (x 10%) 00000


00110

69229

Faithful and differential taxa:Salix uva-ursi 44444

Solidago cutleri 21+1+

Constants:Cetraria islandica 22212

Cetraria nivalis 22111

Carex bigelowii 21112

Agrostis mertensii 222.1

Juncus trifidus 2112.

Diapensia lapponica 1222.

Rhododendron lapponicum 11.1.

Other taxa:Minuartia groenlandica 1....

Cladina rangiferina .2...

Vaccinium cespitosum .+...

Vaccinium uliginosum ..1..

Diapensia lapponica–Rhododendron lapponicumcommunity. Table 9: samples 134–152, Group 9 inFigures 3, 5 and 7Upper-alpine wind-exposed, snow-free communitydominated byDiapensia lapponica, Juncus trifidus,Rhododendron lapponicum,andLoiseleuria procum-bens, accompanied byCarex bigelowii, Potentillatridentata,andVaccinium uliginosum.

Carex bigelowii–Solidago cutleri community. Table10: samples 153–169, Group 10 in Figures 3, 5 and 7Alpine sedge meadows dominated byCarex bigelowiiaccompanied byPotentilla tridentata, Solidago cut-leri, Minuartia groenlandica, Agrostis mertensii,andJuncus trifidus.

Table 12. Deschampsia flexuosa–Solidago cutlericommunity.Reference no.: 175, 176, 177, 178. Mt. Washington, southface, 09/16/95/05,10,13,12. 179, 180, 181. Close to TuckermanJunction, 09/18/95/09,37,10. 182, 183. Tuckerman Ravine Trail,09/18/95/35,36.


222222222

Plant community variant ---------

Relev́e No. 111111111

777778888

567890123

Altitude (x 10 m) 111111111

877766655

383300155

Slope (x 10%) 300000000


001111112

680000000

Faithful and differential taxa:Deschampsia flexuosa 323242323

Solidago cutleri 112222333

Vaccinium cespitosum 3332..11.

Cornus canadensis .+1211..1

Coptis groenlandica .11.211.1

Veratrum viride ...123414

Geum peckii ....22222

Dryopteris campyloptera .....2121

Scirpus caespitosusvar. callosus .....+111

Lycopodium annotinum ..1.11...

Sphagnumsp. ....112..

Constants:Carex bigelowii 223332123

Other taxa:Carex brunnescens 111......

Juncus trifidus .1+......

Cetraria islandica .1.......

Vaccinium uliginosum ...1.....

Agrostis mertensii ...1.....

Calamagrostis canadensis ......1.1

Thelypteris phegopteris .......12

Dennstaedtia punctilobula .......1+

Luzula parvifloravar. melanocarpa ......1..

Salix uva-ursi–Solidago cutleri community. Table 11:samples 170–174, Group 11 in Figures 3, 5 and 7Alpine dwarf shrub willow community dominated bySalix uva-ursi, accompanied bySolidago cutleri, Ce-traria nivalis, Cetraria islandica, Carex bigelowii,Agrostis mertensii, Juncus trifidus, Diapensia lappon-ica, andRhododendron lapponicum.

98

Table 13.Summary information of CA ordination analyses.

Axis 1 Axis 2 Axis 3 Axis 4 Sum of eigenvalues

Overall data matrix:Eigenvalues 0.900 0.586 0.538 0.347 6.379

Cumulative percentage variance 14.1 23.3 31.7 37.2

Forests:Eigenvalues 0.364 0.167 0.134 0.091 1.667


Krummholz and alpine vegetation:Eigenvalues 0.672 0.632 0.382 0.326 5.028


Krummholz and alpine ericaceous vegetation:Eigenvalues 0.529 0.391 0.285 0.221 3.077


Remaining alpine vegetation:Eigenvalues 0.738 0.372 0.337 0.285 3.392


Figure 8. Box plots showing the altitudinal distribution of thetwelve plant communities described, and the estimated boundariesbetween montane, subalpine, and alpine bioclimatic belts. Plantcommunity numbers correspond to those of the twelve tables andAppendix 2.

Deschampsia flexuosa–Solidago cutleri community.Table 12: samples 175–183, Group 12 in Figures 3, 5and 7Alpine snowbank community characterized byDe-schampsia flexuosa, Solidago cutleri, Veratrum viride,

Geum peckii, Vaccinium cespitosum, Carex bigelowii,Coptis groenlandica, andCornus canadensis.

Ordination of the remaining alpine vegetation

The ordination diagrams obtained using CA (Fig-ures 7c, 7d) illustrate two main gradients. Axis 1 rep-resents the snow-cover gradient, starting by the snow-free and wind-exposed communities ofDiapensialapponica–Rhododendron lapponicum(group 9) andMinuartia groenlandica–Agrostis mertensii(group 8)at the left side, following bySalix uva-ursi–Solidagocutleri (group 11) andCarex bigelowii–Solidago cut-leri (group 10). At the end of the sequence are lo-cated the snow-banks communities ofDeschampsiaflexuosa–Solidago cutleri(group 12). Axis 2 isolatesDiapensia–Rhododendron lapponicum(group 9) andSalix uva-ursi–Solidago cutleri(group 11) fromMin-uartia groenlandica–Agrostis mertensii(group 8) andCarex bigelowii–Solidago cutleri(group 10). Fig-ure 8 plus CA ordinations suggest that distributionof plant communities within the alpine belt has nocorrelation with altitude, but with mesotopographicconditions (snow accumulation, exposure and cryotur-bation, slope position, and soil moisture).

Probability ellipses and Student’s t-test

After the plant communities classification, computerprogram ELLIPSE (Podani 1993, 1994) superimposed

99

Table 14.Probabilities that the null hypothesis is true among the twelve groups, i.e., the probabilities among every pair of plant communitiesof being the same community (axis 1 and 2 of CA ordinations, respectively, at 95% significance level). Bold symbols indicate probabilitiesP > 0.40× 10−3.

CA 1 2 3 4 5 6 7 8 9 10 11 121 12 0.28E − 07 13 −0.78E − 06 0.046 14 −0.79E − 06 0.98E − 07 0.83E − 07 15 −0.15E − 06 0.40E − 07 −0.79E − 06 −0.78E − 061

6 −0.80E − 06 −0.78E − 06 0.75E − 07 −0.36E − 08 −0.77E − 06 17 −0.80E − 06 −0.80E − 06 −0.40E − 07 0.62E − 07 −0.82E − 06 0.35E − 04 18 −0.79E − 06 −0.81E − 06 0.93E − 07 0.76E − 08 −0.80E − 06 0.17E − 06 0.24E − 06 19 −0.80E − 06 −0.81E − 06 0.14E − 06 0.45E − 07 −0.79E − 06 −0.15E − 06 0.39E − 07 0.44E− 03 110 −0.80E − 06 −0.81E − 06 0.82E − 08 0.55E − 07 −0.80E − 06 0.19E − 06 −0.45E − 07 0.75E− 02 0.13E − 06 111 −0.80E − 06 −0.80E − 06 0.29E − 07 −0.13E − 07 −0.81E − 06 0.69E − 07 0.77E − 05 0.130 0.150 0.13E − 05 112 −0.80E − 06 −0.80E − 06 −0.90E − 07 0.33E − 07 −0.79E − 06 0.11E − 07 0.52E − 07 0.62E − 06 0.14E − 06 −0.68E − 08 0.38E − 05 1

classification results on Figure 3c by drawing ellipsesof equal concentration around the centroids of clus-ters (Mardia et al. 1979; Lagonegro & Feoli 1985) at95% probability level (Figure not shown). The meanand standard deviation of each ordination dimensionfor every community were calculated. Differences be-tween means among the twelve communities weretested by Student’st-test, giving the probabilities thatthe null hypothesis is true, i.e., the probabilities amongevery pair of plant communities of being the samecommunity. Results of the Student’st-test are shownin Table 14.

The highest probability of the null hypothesis tobe true, i.e., the probability of being the same plantcommunity, based on axes 1 and 2 of CA ordination(P = 0.150) is that betweenDiapensia lapponica–Rhododendron lapponicum(group 9) andSalix uva-ursi–Solidago cutleri(group 11). This result seems toagree with Daniëls (1994) who considersSalix uva-ursi characteristic toLoiseleurio–Diapensioncom-munities. Next lower probability (P = 0.130) isbetweenMinuartia groenlandica–Agrostis mertensii(group 8) and group 11, also belonging toLoiseleurio–Diapension. Next lower probability (P = 0.046) is be-tweenBetula cordifolia–Sorbus americana(group 2)andAbies balsamea–Betula alleghaniensis(group 3).This seems to be related to the similarity in theirflora (see Tables 2 and 3, and Appendix 2), but thefirst one is a soft-wood secondary forest ofAbiesbalsamea–Betula cordifoliacommunity (group 4),whereas the second one is anAbies balsamea–Picearubensdominated community growing on xeric soilsin contact with Fagus grandifolia–Acer saccharumcommunity (group 1). At the beginning of the sub-

alpine belt group 2 seems to be the secondary forest ofgroup 3 (see Figure 8). Next lower probability (P =0.75×10−2) is between group 8 andCarex bigelowii–Solidago cutleri(group 10). Next lower probability isbetween groups 8 and 9 (P = 0.44× 10−3), both ofthem belonging again toLoiseleurio–Diapension. Theremaining probabilities are lower than 10−4.

Acknowledgements

This study was possible thanks to a postdoctoral fel-lowship awarded to the author by the Ministry ofEducation and Science of Spain for staying at QueensCollege of the City University of New York, and TheNew York Botanical Garden during 1995–1996. Thispaper improved with the help of Dr Andrew M. Greller(QC of CUNY), Dr Leslie F. Marcus (QC of CUNY),Dr D. S. A. Wijesundara (then of the QC of CUNY),Dr Enrique Forero (then of the NYBG), Dr SalvadorRivas-Martínez (Dep. Biología Vegetal II, UniversidadComplutense de Madrid), and two anonymous refer-ees. Dr Víctor J. Rico (DBV II of UCM) revised thelichenic material. The author is grateful to all of them.

References

Antevs, E. 1932. Alpine zone of Mt. Washington Range. Auburn,Maine, 118 pp.

Barkman, J. J., Moravec, J. & Rauschert, S. 1986. Code ofphytosociological nomenclature. Vegetatio 67 (3): 145–195.

Barnes, B. V. 1991. Deciduous forests of North America. Pp. 219–344. In: Röring, E. & Ulrich, B. (eds), Ecosystems of the World,Vol. 7. Temperate deciduous forests. Elsevier, New York.

100

Bergeron, J. F., Germain, L. & Grandtner, M. M. (dir.). 1984. Po-tentiel du mont du Lac des Cygnes en vue de la création d’uneréserve écologique. 104 pp. Lab. écol. for., Univ. Laval, Québec.

Billings, M. P., Chapman, C. A., Chapman, R. W., Fowler-Billings,K. & Loomis Jr., F. B. 1946. Geology of the Mt. WashingtonQuadrangle. New Hampshire. Geol. Soc. Amer. Bull. 57: 261–274.

Bliss, L. C. 1963. Alpine plant communities of the presidentialrange, New Hampshire. Ecology 44: 678–697.

Box, E. O. 1981. Macroclimate and Plant Forms: An Introductionto Predictive Modeling in Phytogeography. 258 pp. [Tasks forVegetation Science, vol. 1]. Dr. Junk Publishers, The Hague.

Braun, E. L. 1950. Deciduous Forests of Eastern North America.McGraw-Hill, New York, 596 pp., map.

Braun-Blanquet, J. 1964. Pflanzensoziologie. Grundzüge der Veg-etationskunde. 3rd ed. Springer-Verlag, Vienna, New York,865 pp.

Daniëls, F. J. A. 1982. Vegetation of the Angmagssalik District,Southeast Greenland, IV. Shrub, dwarf shrub and terricolouslichens. Medd. Grønl. Biosci. 10: 1–78.

Daniëls, F. J. A. 1994. Vegetation classification in Greenland. J. Veg.Sci. 5: 781–790.

Davis, M. B. 1976. Pleistocene biogeography of temperate decidu-ous forests. Geosci. Man 13: 13–26.

Davis, M. B. 1981. Quaternary history and the stability of forestcommunities. Pp. 132–153. In: West, D. C., Shugart, H. H. &Botkin, D. B. (eds), Forest succesion, concepts and application.Springer-Verlag, Berlin.

Delcourt, P. A. & Delcourt, H. R. 1979. Late Pleistocene andHolocene distributional history of the deciduous forest in south-eastern United States. Pp. 79–107. In: Lieth, H. & Landolt, E.(eds), Contributions to the knowledge of flora and vegetation inthe Carolinas, vol. 1. Stiftung Rübel, Zürich.

Ellenberg, H. & Mueller-Dombois, D. 1967a. A key to Raunkiaerplant life forms with revised subdivisions. Ber. Geobot. Inst. Rü-bel 37: 56–73. (Reprinted as Appendix A in Mueller-Domboisand Ellenberg 1974).

Ellenberg, H. & Mueller-Dombois, D. 1967b. Tentativephysiognomic-ecological classification of plant formationsof the Earth. Ber. Geobot. Inst. Rübel 37: 21–55. (Finalized 1937for UNESCO and reprinted as Apendix B in Mueller-Domboisand Ellenberg 1974).

Esslinger, T. L. & Egan, R. S. 1995. A Sixth Checklist of the lichen-forming, lichenicolous, and allied Fungi of the ContinentalUnited States and Canada. The Bryologist 98 (4): 467–549.

Etheridge, D. M., Steele, L. P., Langenfelds, R. L, Francey, R. J.,Barnola, J. M. & Morgan, VI. 1998. Historical CO2 records fromthe Law Dome DE08, DE08-2, and DSS ice cores. In Trends: ACompendium of Data on Global Change. Carbon Dioxide Infor-mation Analysis Center, Oak Ridge National Laboratory, OakRidge, Tennessee, USA.

Fenneman, N. M. 1938. Physiography of Eastern United States.McGraw-Hill, New York, 714 pp.

Géhu, J. M. & Rivas-Martínez, S. 1981. Notions fondamentalesde phytosociologie. In: Cramer J. (ed.), Syntaxonomie: 5-33,Vaduz.

Gleason, H. A. & Cronquist, A. 1991. Manual of Vascular Plantsof Northeastern United States and Adjacent Canada. 2nd ed. TheNew York Botanical Garden, Bronx, New York.

Grandtner, M. M. 1989–1990. Écologie forestière II. 143 pp. Lab.écol. for., Dép. sci. for., Fac. for. & géod. Univ. Laval, Québec.

Greller, A. M. 1988. Deciduous forests. Pp. 287–316. In: Bar-bour, M. G. & Billings, W. D. (eds), North American TerrestrialVegetation. Cambridge University Press, Cambridge.

Houghton, J. T., Meira Filho, L. G., Callander, B. A., Harris,N., Kattenberg, A., & Maskel, K. (eds). 1996. Climate change1995 - the science of climate change, contributions of WorkingGroup 1 to the Second Assessement Report of the Intergovern-mental Panel on Climate Change. Cambridge University Press,Cambridge.

Keeling, C. D. & Whorf, T. P. 1998. Atmospheric CO2concentrations–Mauna Loa Observatory, Hawaii, 1958–1997(revised August 1998). NDP-001. Carbon Dioxide InformationAnalysis Center, Oak Ridge National Laboratory, Oak Ridge,Tennessee.

Küchler, A. W. 1964. The potential natural vegetation of the con-terminous United States. Am. Geogr. Soc., Spec. Publ., No. 36:154 pp., map.

Lagonegro, M. & Feoli, E. 1985. The use of ellipses of equalconcentration to analyse ordination vegetation patterns. Stud.Geobot. 5: 143–165.

Legendre, P. 1990. Quantitative methods and biogeographic analy-sis. Pp. 9–34. In: Garbary, D. J. and South, G. R. (eds), Evolu-tionary biogeography of the marine algae of the North Atlantic.NATO ASI Series, Vol. G22. Springer-Verlag, Berlin.

Mann, M. E., Bradley, R. S. & Hughes, M. K. 1998. Global-scale temperature patterns and climate forcing over the past sixcenturies. Nature 392: 779–787.

Mann, M. E., Bradley, R. S. & Hughes, M. K. 1999. Northern Hemi-sphere temperatures during the past millennium: Inferences,uncertainties, and limitations. Geophys. Res. Lett. 26: 759–762.

Marcotte, G. & Grandtner, M. 1974. Etude écologique de la végéta-tion forestière du Mont Mégantic. Serv. Rech. Dir. Gén. Forêts.Min. Ter. For. Mém. 19: I-XX, Québec, pp. 1–556.

Mardia, K. V., Kent, J. T. & Bibby, J. M. 1979. Multivariate analysis.Academic Press, London.

Mitchell, Jr., J. M. 1977. Record of the past; lessons for the future.Pp. 15–25. In: Living with Climatic Change, II. Mitre Corp.,McLean, Va.

Miyawaki, A. (ed.). 1988. Vegetation of Japan vol. 9. Hokkaido.Shibundo Co., Ltd. Publishers, Tokyo.

Miyawaki, A., Iwatsuki, K. & Grandtner, M. M. (eds). 1994. Vegeta-tion in Eastern North America. University of Tokyo Press, Tokyo,515 pp.

Mucina, L. 1997. Conspectus of Classes of European Vegetation.Folia Geobot. Phytotax. 32: 117–172.

Mucina, L. & van der Maarel, E. 1989. Twenty years of numericalsyntaxonomy. Vegetatio 81: 1–15.

Mueller-Dombois, D. & Ellenberg, H. 1974. Aims and methods ofvegetation ecology. Wiley and Sons, New York.

Nakamura, Y. & Grandtner, M. M. 1994. A comparative study of thealpine vegetation of eastern North America and Japan. Pp. 335–347. In: Miyawaki, A., Iwatsuki, K. & Grandtner, M. M (eds),Vegetation in Eastern North America. University of Tokyo Press.

Nakamura, Y., Grandtner, M. M. & Villeneuve, N. 1994. Borealand Oroboreal Coniferous Forests of Eastern North America andJapan. Pp. 121-154. In: Miyawaki, A., Iwatsuki, K. & Grandtner,M.M (eds), Vegetation in Eastern North America. University ofTokyo Press, Tokyo.

National Oceanic and Atmospheric Administration (NOAA). With-out date. Climate of New Hampshire. Climatography of theUnited States no. 60: 1–15. National Climatic Center, Asheville,N.C.

Okuda, S. 1994. Deciduous Hardwood Forests Communities inEastern North America, including some conifer forests andshrubs communities. Pp. 155–201. In: Miyawaki, A., Iwat-suki, K. & Grandtner, M.M (eds), Vegetation in Eastern NorthAmerica. University of Tokyo press.

101

Pacala, S. W., Canham, C. D., Saponara, J., Silander Jr., J. A.,Kobe, R. K. & Ribbens, E. 1996. Forest models defined by fieldmeasurements: estimation, error analysis and dynamics. Ecol.Monogr. 66 (1): 1–43.

Podani, J. 1989a. New combinatorial clustering methods. Vegetatio81: 61–77.

Podani, J. 1989b. Comparison of ordinations and classifications ofvegetation data. Vegetatio 83: 111–128.

Podani, J. 1993. syn-tax-pc. Computer Programs for MultivariateData Analysis in Ecology and Systematics. Version 5.0. ScientiaPublishing, Budapest.

Podani, J. 1994. Multivariate Analysis in Ecology and Systematics.SPB Academic Publishing, Amsterdam, 316 pp.

Podani, J. & Dickinson, T. A. 1984. Comparison of dendrograms: amultivariate approach. Can. J. Bot. 62: 2765–2778.

Raunkiaer, C. 1937. Plant life forms. 104 pp. Clarendon, Oxford.Rivas-Martínez, S. 1987. Nociones sobre Fitosociología, Bio-

geografía y Bioclimatología. Pp. 17–46. In: Peinado, M. &Rivas-Martínez, S. (eds), La Vegetación de España. Serv. Publ.Univ. Alcalá, Madrid.

Rivas-Martínez, S. 1997. Syntaxonomical synopsis of the poten-tial natural plant communities of North America, I. ItineraGeobotanica 10: 5–148.

Rivas-Martínez, S., Sánchez-Mata, D. & Costa, M. 1999. NorthAmerican boreal and western temperate forest vegetation. ItineraGeobotanica 12: 5–316.

Rübel, E. F. 1930. Pflanzengesellschaften der Erde. Verlag HansHuber, Bern, 464 pp.

Sneath, P. & Sokal, R. 1973. Numerical taxonomy. Freeman, SanFrancisco.

ter Braak, C. J. F. 1985. Correspondence Analysis of incidenceand abundance data: properties in terms of a unimodal responsemodel. Biometrics 41: 859–873.

ter Braak, C. J. F. 1995. Ordination. Pp. 91–173. In: Jongman,R. H. G., ter Braak, C. J. F. & van Tongeren, O. F. R. (eds),Data analysis in community and landscape ecology. CambridgeUniversity Press, New York.

U. S. Department of Agriculture. 1978. Ecosystems of the UnitedStates. U. S. D. A. For. Serv. Rare II Map B. Washington D. C.

van der Maarel, E. 1979. Transformation of cover-abundance val-ues in phytosociology and its effects on community similarity.Vegetatio 39: 97–114.

Walker, M. D., Walker, D. A. & Auerbach, N. A. 1994. Plantcommunities of a tussock tundra landscape in the Brooks RangeFoothills, Alaska. J. Veg. Sci. 5: 843–866.

Walter, H. 1985. Vegetation of the Earth and Ecological Systems ofthe Geo-biosphere. 3rd. ed. Springer-Verlag, Berlin.

Walter, H. & Lieth, H. 1960–1967. Klimadiagramm-Weltatlas.Fischer, Jena.

Westhoff, V. & van der Maarel, E. 1978. The Braun-Blanquet ap-proach. Pp. 287–399. In: Whittaker, R. H. (ed.) Classification ofplant communities. Dr. Junk Publishers, The Hague.

Whittaker, R. H. 1975. Communities and Ecosystems. 2nd. ed.MacMillan Publ., New York, 387 pp.

Appendix 1. Field sampling design. The sampling was done using the centralized replicate sampling procedure (Mueller-Dombois & Ellenberg1974). Plot locations were subjectively chosen between the two meteorological stations, in areas of homogeneous vegetation, according tothe following plant-forms and physiognomic-ecological plant formations (Rübel 1930; Raunkiaer 1937; Braun-Blanquet 1964; Ellenberg &Mueller-Dombois 1967a,b; Whittaker 1975; Box 1981).

Plant forms Plant formations Examples

1. Deciduous summergreen broadleavedhardwood trees

Hardwood forests Fagus grandifolia, Acersp. pl.

2. Deciduous summergreen broadleavedsoftwood trees

Softwood secondary forests Betula cordifolia, Betula alleghaniensis

3. Evergreen boreal/subalpine needle-leaved trees

Boreal/Subalpine needle forests Abies balsamea, Picea rubens

4. Evergreen boreal/subalpine needle-leaved treeline krummholz

Krummholz Abies balsamea, Picea mariana

5. Arctic/Alpine dwarf-shrubs Arctic/alpine heath, prostrate willow vege-tation

Vaccinium uliginosum, Ledum groen-landicum, Empetrum hermaphroditum,Salix uva-ursi

6. Arctic/Alpine dwarf cushion shrubs Arctic/alpine dwarf cushion shrub vegeta-tion

Rhododendron lapponicum, Loiseleuriaprocumbens, Diapensia lapponica

7. Grasses Sedge meadows Carex bigelowii

8. Summergreen megaforbs Megaforb snowbanks Veratrum viride

102

Appendix 2. Synoptic table of all vegetation communities. Bold symbols indicate faithful and differential taxa for one group.Regular boxes indicate taxa preferential to multiple groups. 1.Fagus grandifolia–Acer saccharum.2.Betula cordifolia–Sorbus amer-icana. 3.Abies balsamea–Betula alleghaniensis.4.Abies balsamea–Betula cordifolia.5.Picea mariana–Abies balsamea.6.Vacciniumuliginosum–Cetraria islandica.7.Empetrum hermaphroditum–Vaccinium cespitosum.8.Minuartia groenlandica–Agrostis mertensii.9.Di-apensia lapponica–Rhododendron lapponicum.10.Carex bigelowii–Solidago cutleri.11.Salix uva-ursi–Solidago cutleri.12.Deschampsiaflexuosa–Solidago cutleri.

103

Appendix 2. Continued.

Classification and ordination of plant communities along an altitudinal gradient on the Presidential...

Documents

Transcript of Classification and ordination of plant communities along an altitudinal gradient on the Presidential...