temporal trends in plant species composition on mined sand...

Australian Journal of Ecology (1992) 17, 241-254

Temporal trends in plant species composition on minedsand dunes in Myall Lakes National Park, Australia

R. T. BUCKNEY AND D. A. MORRISONDepartment of Applied Biology, University of Technology, Sydney, PO Box 123,Broadway, NSW 2007, Australia

Abstract The floristic composition of the vegetation of mined and unmined sand dunes atBridge Hill, in Myall Lakes National Park, was studied from 1982-90 inclusive. Data frommined sites ranging in age from 2-15 years post mining, with replication of time since miningin both time and space, were incorporated in the study. The mined part of the Bridge Hill duneIS very different in plant species composition compared with either the dune prior to mining orto the adjacent unmined dunes. The mined dune also displays a temporal development ofspecies composition over the period 2-15 years post mining, the dominant trend being areduction in similarity to that of the dune prior to mining. Mining resulted in significantincreases in the abundance of six introduced species, and in significant differences in theabundance of 49% of the native species. Species richness and diversity increased during theperiod 2-15 years post mining, and a significant component of this could be attributed to thepresence of the introduced species.

INTRODUCTION

Sand mining has been a controversial activity inAustralia, generating considerable public interestbecause it has been concentrated in the scenic andsensitive coastal zone (Gilpin 1990). The sclero-phyllous communities along the eastern and south-western coasts usually occur on low-nutrient soilsand as a result have often remained relatively un-disturbed by Europeans. About 30 years ago ineastern Australia, and 15 years ago in Western Aus-tralia, mining for heavy minerals commenced on amuch larger scale than previously, posing landmanagement problems in these communities (Gil-pin 1990)

This paper reports the results of a 9-year studyof the floristic composition of the mined andunmined areas at Bridge Hill, in Myall LakesNational Park, New South Wales, Australia, incor-porating data from mined sites ranging in age from2 to 15 years post mining. No such long-termstudies of post mining vegetation patterns havebeen reported previously from eastern Australia.

Several studies of the temporal patterns postmining in the Bridge Hill area have been pub-lished, including those for small mammals (Fox &Fox 1984; Twigg et al. 1989), ants (Haering & Fox

Accepted for publication January 1992.

1987; Fox 1990) and lizards (Twigg & Fox 1991),but there appears to have been no previous study ofthe vegetation. Our study addressed the followingquestions: (i) What are the patterns of plant speciescomposition and abundance between areas of theBridge Hill dune at different ages post mining?(ii) How do these patterns compare with those inareas on the dune prior to mining? and (iii) How dothese patterns compare with those in the com-munities on nearby unmined sand?

Geographic setting

Myall Lakes National Park, approximately 270 kmnorth of Sydney, is an extensive region of sanddeposition around previous rocky islands and head-lands, trapping a series of large lakes. A smallNational Park (of about 15 000 ha) was establishedin 1971, and its size was nearly doubled in 1977.The area consists of an inner barrier of parallel andparabolic Pleistocene sand dunes, fronted by anouter barrier of parabolic Holocene dunes (Thomet al. 1981). The Bridge Hill sand system is a largetransgressive Holocene dune overlying the Pleis-tocene sand, and is described in detail by Carolin(1970), Thom etal. (1981) and Myerscough &Carolin (1986).

Prior to the commencement of sand mining, theMyall Lakes area was relatively undisturbed, suf-

242 R. T. BUCKNEY AND D. A. MORRtSON

fering only from limited selective logging after the1880s. The original vegetation of the Bridge Hilldune was a dry sclerophyll forest; structurally a tallopen-forest, dominated by Eucalyptus pilularis andAngophora costata, with a tall understorey oi Bank-sia serrata, and with Pteridium esculentum andImperata cylindrica prominent in the ground layer(Myerscough & Carolin 1986).

Mining of sands for a number of minerals,chiefly rutile, zircon and monazite, commenced inthe Myall Lakes area in 1965. Mining commencedin the Bridge Hill area in 1974 (Fig. 1) and it ceasedin 1983. During that time, the dredge continuouslyprocessed the northern slope of the large ridge run-ning west to Bridge Hill, creating a band of minedsand approximately 3 km long (Fox & Fox 1984).Rehabilitation of the vegetation commenced im-mediately the mined area was vacated by thedredge. Thus, the current vegetation of the minedpart of the Bridge Hill dune displays a time se-quence of rehabilitated areas, with the oldest dis-turbed vegetation nearest the coast. The highestpoint of the dune is over 100 m above sea level.

The rehabilitation procedure consisted of theremoval of the vegetation, the burning of largetrees, stripping and storage of the topsoil for 6-18months, reshaping of the mined area to contoursapproximating those prior to mining, the respread-ing of the topsoil, and the broadcast of some nativeseeds and planting of seedlings of the dominanttrees and shrubs at densities related to pre-miningdensities ofthese plant species (Fox & Fox 1978). Acover crop of a sterile hybrid Sorghum sp. providedinitial stabilization of the topsoil.

METHODS

Our studies were conducted in March of the years1982-90 inclusive. We estimated species abun-dance for each sample using the nested quadrattechnique of Outhred (1983), with importancescores assigned to each species using 13 square sub-quadrats varying from 0.1 to 1000 m^. This tech-nique produces abundance scores (on a scale of1-13) that are functionally equivalent to frequen-cies (Morrison, Le Brocque & Clarke unpubl.

a /Hawks Nest - Seal Rocks Road

0 1 2 3 4 5

Fig. 1. Map of the study area, showing mined area (shaded, with numbers indicating year of mining), unmined sample locations (•) andtransmission line sample area (o).

REVEGETATION OF MINED SAND DUNES 243

data), but takes no longer than the collection ofpresence-absence data. All species nomenclaturefollows Myerscough and Carolin (1986) and Jacobsand Pickard (1981).

We selected quadrat centres in the mined area ofthe dune from four areas (A-D) each year, to repre-sent locations mined in each of the years 1974-5,1977-8, 1981 and 1983 respectively (Fig. 1;Table 1). As far as possible, we located quadratcentres so as to minimize dependence betweensamples in the same area between years. Thesequence of sampling in the mined area yieldedreplication of each age since mining each year, aswell as replicating age since mining at severalplaces along the dune (Table 1); this avoids most ofthe auto-correlation problems associated withchronosequence analysis (Twigg etal. 1989).When quadrats were duplicated at each samplingtime, their centres were approximately 35 m fromeach other.

Quadrats sampled on the Bridge Hill dune in1982-84, immediately prior to mining, wereplaced in the area to be mined last (i.e. in 1983) andin closely adjacent areas immediately west of theSeal Rocks Road. In 1985-90, comparison quad-rats were placed on the adjacent unmined dunesmost accessible from each of the mined study areas,usually just to the north of the mine path. In 1985,we also located eight quadrats on Holocene sandnear Kataway Bay (Fig. 1), 4 km south of BridgeHill, to identify any spatial variation in speciescomposition over larger distances (Inouye 1988).Two samples were also taken under a transmissionline southwest of the mined area; this area iscleared of vegetation periodically, and providesdata on a disturbed, but unmined, area.

Data analysis

Hybrid multidimensional scaling (Belbin 1989)was used to investigate the pattern of plant speciescomposition between the areas on the mined duneat different ages post mining (Chambers 1983), aswell as between the mined and unmined areas.This ordination technique is a hybrid betweenmetric and non-metric multidimensional scalingthat attempts to combine the best features of eachof the two techniques (Faith etal. 1987), A two-dimensional ordination was used, with the Bray-Curtis dissimilarity measure and a cut point at dis-similarity = 0.8. The temporal patterns within themined and unmined areas in each ordinationanalysis were investigated by calculating the ordi-nation distance of each sample quadrat from theordination centroid of all of the unmined quadratsin that analysis (Bloom 1980).

The categorical nature of the pattern was testedusing clustering by indicator species analysis (Hill1979). This is a polythetic divisive technique thathas proved effective in floristic studies (Hill et al.1975).

The pattern of abundance of each species be-tween the different age groups on the mined dunewas investigated using non-parametric Kruskal-Wallis tests (Wilkinson 1987), significance beingassessed at t h e P = 0.05 level. The pattern of abun-dance of each plant species between the mineddune and the dune prior to mining, as well as theadjacent unmined dunes, was assessed using non-parametric Mann-Whitney U-tests (Wilkinson1987). Non-parametric tests were used because fre-quency data are likely to approximate a Poissondistribution rather than a normal distribution

Table 1. Number of quadrats sampled in each of the areas in Myall Lakes National Park for each year of the study

Area 1982 1983 1984Year sampled

1985 1986 1987 1988 1989 1990

Mined 1975 (area A)Mined 1978 (area B)Mined 1981 (area C)Mined 1983 (area D)Original unmined duneAdjacent unmined duneKataway BayTransmission line

17 12 124(2)

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8

2(15)2(12)2(9)

6

The number in brackets is the time (in years) since mining of the area at the time of sampling.

244 R. T. BUCKNEY AND D, A. MORRISON

(NichoUs 1991). It should also be remembered thatabout 8 out of the 163 results could have a prob-ability value of 0,05 or less by chance alone for eachof the three tests.

Importance scores vary more or less linearly withdensity over a wide range of values (Outhred 1983),so it was also possible to estimate Shannon-Weinerspecies diversity indices for each quadrat fromthese data.

RESULTS

A total of 163 species were encountered in thisstudy (see Appendix I), 140 (86%) of them occur-ring in the unmined areas and 112 (69%) of themon the mined parts of the Bridge Hill dune.Thirteen (8%) of these species are not native to thearea; eight of these are restricted to the mineddune, while the remainder occur only in theunmined areas in very low abundances.

The quadrats within the mined area have amuch higher similarity in floristic compositionamong themselves (average 47%) than with quad-rats from any of the unmined areas (average 35%;Table 2), On the other hand, the quadrats withinthe unmined areas on and adjacent to Bridge Hillhave only a slightly higher similarity among them-selves than they do compared with quadrats fromthe other unmined areas (Table 2), while the quad-rats within the unmined areas at Kataway Bay andthe transmission lines have a much higher simi-larity among themselves (Table 2). This indicatesthat there is as much floristic diversity within theunmined areas at Bridge Hill as there is over amuch larger geographical area.

The ordination of the mined sites shows atemporal continuum in species composition fromthose quadrats in areas mined most recentlythrough to those mined earliest (Fig. 2); and theclustering confirms this, separating the youngest

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(2-6 years post mining) sites from the oldest (11-15years post mining; Fig, 2). However, with only afew exceptions, the pre-mining quadrats on themined dune are distinguishable from the unminedquadrats on the adjacent dune (Fig. 3). Neverthe-less, no consistent trends were detected within theunmined sites, either over the 9 years of sampling(Fig. 4a) or when related to age post mining(Fig. 4b). Thus, the trend within the mined sitescannot be associated with distance from the coastor with annual variation; it represents the temporaldevelopment of the mined areas. This temporalcontinuum reflects significant changing abun-dance of 28 species (25% of those found on themined dune) post mining, with 20 species increas-ing in abundance through time, five decreasing,and three increasing then decreasing (Appendix I).

Table 2. Average similarity (1 —Bray-Curtis dissimilarity) between quadrats in each of the sample areas at Myall Lakes National Park(excluding the similarity of each quadrat to itself)

Area

Mined duneOriginal duneAdjacent duneKataway BayTransmission line

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In particular, 10 species appeared later on themined dune that were not found at all in the firstfew years after mining.

The ordination and clustering comparisons ofthe mined dune before and after mining show aclear floristic distinction between the two data sets(Fig. 5). This distinction corresponds to differ-ences in abundance of 64 species (46% of those inboth data sets), with 38 species having increasedabundance after the dune was mined and 26 show-ing decreased abundance (Appendix I). In particu-lar, six introduced species and 12 native speciesthat were not present on the original dune ap-peared on the mined dune, while seven speciesfound on the original dune were not found on themined dune. The ordination analysis also showsthat the mined areas are becoming significantlyless similar floristically to the original dunethrough time (Fig. 6a).

The ordination and clustering comparisons ofthe mined dune with the adjacent unmined areasalso show a floristic distinction between the twodata sets, with only two quadrats being misclassi-fied (Fig. 7). This distinction corresponds to dif-ferences in abundance of 46 species (31% of thosein both data sets), with 23 showing greater abun-dance on the mined dune and 23 showing lowerabundance (Appendix I). In particular, seven

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Fig. 4. Ordination distance (based on Fig. 3) of each of the samplequadrats in the unmined parts of the Bridge Hill area from theordination centroid of the quadrats for (a) each of the years sampledand (b) the adjacent dune relative to the time since mining of thenearby part of the mined dune. See text for an explanation. In (a)the lines are the mean distance for the original unmined dune andfor the samples from the adjacent unmined dune, while in (b) theyare the mean distance through time for each of the four areas(A-D) studied. For (a) the Pearson correlation coefficient isr = -0.132, P>0.05, and for (b) it is r = -0.171, P>0.05.

species (two introduced) were found on the mineddune but never on the adjacent dune, while ninespecies occurring on the adjacent dune were notfound on the mined dune. Nevertheless, there is noconsistent temporal pattern of species compositionwithin the mined dune compared with the adjacentareas (Fig. 6b). The quadrats sampled at KatawayBay and under the transmission lines are composi-tionally more similar to the other unmined areasthan they are to the mined dune (Table 2;Fig. 7).

246 R. T, BUCKNEY AND D, A, MORRISON

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Both the species richness (Fig, 8a) and diversity(Fig. 8b) within quadrats increased with time postmining. These attributes vary almost completelywithin the range found for the adjacent dune, butreach values approximately 25% higher than inthose samples taken prior to mining on the dune.This excess of species can be substantially ac-counted for by the introduced species, which reacha maximum diversity about 5 years post mining(Fig. 8c).

DISCUSSION

The best sampling technique for assessing the im-pact of human disturbance on the abundance ofbiological populations appears to be the BACI de-sign of Stewart-Oaten et al. (1986), but this was notpossible in our study because no samples weretaken in the Bridge Hill area prior to the com-mencement of mining in 1974, Failing this, themost common technique is to extrapolate temporaltrends from a series of different-aged samples, thususing space-for-time substitution to produce achronosequence (Pickett 1989). However, thistechnique assumes that all of the other environ-mental variables (e.g. soil, microclimate, fireregime, biotic interactions) contribute equally toeach of the experimental samples, and most not-

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Fig. 6. Ordination distance of each of the sample quadrats on themined area of the Bridge Hill dune from the ordination centroid ofthe unmined quadrats on (a) the Bridge Hill dune prior to mining(based on Fig. 5) and (b) the adjacent dune (based on Fig. 7,excluding Kataway Bay and the transmission lines). See text for anexplanation. The lines are the mean distance through time for eachof the four areas (A-D) studied. For (a) the Pearson correlationcoefficient is r = 0,500, P<0,001, and for (b) it is r = -0.189,P>Q.O5.

ably for stripmine recovery it assumes that therewas no variation in the mining technique throughtime (Picket 1989). These assumptions are in-herent in most long-term studies, and we at-tempted to minimize the limitations ofthe chrono-sequence technique by replicating our samples inboth space and time, rather than by carefully pair-ing environmentally-matched samples in minedand unmined areas. One consequence of this is thatthe within-age variability of the samples is higherthan might otherwise have been obtained.


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However, there are two main conclusions thatarise from this study. First, there is a clear distinc-tion in species composition between the vegetationon the mined dune at Bridge Hill and that on thedune prior to mining as well as that on the adjacentsand dunes. Second, there is a consistent temporaltrend in species richness, diversity and compo-sition of the vegetation with age post mining; thistrend involves decreasing similarity to the vege-tation on the dune prior to mining, but is indepen-dent of the species composition of the adjacentareas. These patterns are contrary to those ex-pected if the revegetation procedure was produc-ing a forest vegetation similar to that existing priorto mining; and they are also not consistent with theproduction of a forest similar to that of the adjacentunmined dunes. The compositional changes havethus occurred on the mined dune in isolation.

We interpret our analyses as indicating thatthere are three distinct groups of plant species inthe Bridge Hill area of Myall Lakes National Park:(i) those that have significantly higher abundanceon the mined area compared to elsewhere (37native species; six introduced species); (ii) thosethat have significantly lower abundance on themined area compared to elsewhere (36 nativespecies); and (iii) those that show no detected dif-

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248 R. T. BUCKNEY AND D. A. MORRISON

ferences in abundance (77 native species; sevenintroduced species of very low abundance). No-table among the native species of the first groupare several members of the Iridaceae, Epacri-daceae, Fabaceae, and Mimosaceae; and the mainintroduced species of this group are Conyza eana-densis., Hypoehoeris radieata, and Eragrostis eilia-nensis. Particularly important species in the secondgroup are the dominant species of the unminedareas: Euealyptus pilularis, Banksia serrata,Pteridium eseulentum, and Imperata eylindriea, aswell as several members of the Proteaceae (seeAppendix I).

After mining, vegetation will rarely establishunaided, and so revegetation usually requires ac-tive rehabilitation, along with the attempted recon-struction of the original environment (Jordan et al.1987). However the actively revegetated com-munity of the mined area of the Bridge Hill dunecan be best characterized to date as reclamation (inthe terminology of Allen 1988) rather than res-toration, as the vegetation has a certain similarityafter mining to that of the unmined area but thereare significant differences in species abundances.These differences can possibly be attributed to anumber of environmental factors, discussedbelow.

First, our data indicate that mining of the BridgeHill dune was a process that encouraged the col-onization of introduced species. The abundance ofweed species, particularly Hypoehoeris radieata,Eragrostis eilianensis and Andropogon virginieus,increased markedly beyond 2-6 years post mining(Appendix I), the period after the death of the firstgrowth of Aeaeia species. These weeds may havebeen encouraged by the more open conditions andthe enrichment of nutrients brought about by thedecomposition of the Aeaeia biomass. Fox (1988),in a study of Pleistocene dunes mined earlier atMyall Lakes, found 13% of the 133 plant speciespresent after mining were introduced weeds, com-pared to our 11% of 112 species; so it seems thatweed invasion may be a general problem of minedsand dunes (cf. Thatcher & Westman 1975).

Second, it is not unusual for revegetation pro-grammes after mining to result in changed abun-dance of native species (Panetta & Groves 1990),and this is often attributed to changes in soil nutri-ent status (Marrs & Gough 1989). This may be theresult of fertilizer usage to ensure rapid earlygrowth of the plants after mining (Specht 1975),

although decomposition of below-ground biomassand the mixing of sand from several layers of thedune could also result in increased soil nutrientlevels. This can dramatically affect the behaviourof the component species, especially on sand dunes(Clark 1975; Specht 1975; Thatcher & Westman1975), with some species (especially weeds)favoured by the increased nutrients and others dis-advantaged. Myerscough and Carolin (1986) havedemonstrated a strong relationship between soilnutrient status and the vegetation composition ofthe Myall Lakes area, with increased podzolizationof the dunes through geological time. So, changednutrient status may explain the dramatic increasein abundance of members of the Fabaceae andMimosaceae, and the decrease in abundance ofmembers of the Proteaceae observed here (cf.Panetta & Groves 1990).

Third, the invasion of plant roots by vesicular-arbuscular mycorrhizae (VAM) is important aftersurface mining (Jasper etal. 1987). For thosenative species with VAM on the Bridge Hill dune,the average percentage of root length infected is5% at 2 years after mining, 7% at 4 years, and 13%at 9 years, while it is 18% on the adjacent unminedHolocene dunes (recalculated from data presentedby BrockhoflF& Allaway 1989). These data are con-sistent with the slow recolonization of the minedarea by VAM through time. Moreover, the averageVAM infection rate for the introduced species onthe mined area is 27% of root length, perhaps help-ing to explain the relative success of these species.In addition, the relatively abundant Epacridaceaespecies on the mined area have their own ericoidectendomycorrhizae, and the abundant Mimos-aceae and Fabaceae species have root nodules aswell as VAM, while the less abundant Proteaceaespecies have no mycorrhizae at all. Thus, root as-sociations may also play an important role in deter-mining the changing floristic composition on themined dune.

Fourth, species characteristic of wet sclerophylland swale areas as well as ground cover and fernspecies (such as Polyseias sambueifolia, Xylomelumpyriforme, Endiandra sieberi, Pomax umbellata, Po-ranthera mierophylla, Pteridium eseulentum andSehizaea bifida) are under-represented on themined dune compared with the other areas,suggesting that relative aridity may be an import-ant ecological determinant of the floristic dif-ferences observed. Potential causes of increased


aridity include a lowered water table due to poordevelopment of the soil profile, increased exposuredue to lack of sufficient vegetation cover andmulch during the early years after mining, and thereduced microtopographic variation on the mineddune due to the artificial recontouring. Theseproblems would be particularly important giventhe northerly aspect of the mined dune face. Suchan effect has been noted after sand mining else-where (Clark 1975), and Carolin (1970) has noted astrong relationship between the level of the watertable and the vegetation composition of the MyallLakes area.

Fifth, a number of the species showing signifi-cantly decreased abundance post mining may alsohave suffered during topsoil storage. This could beparticularly true of rhizomatous species such asPteridium esculentum, and parasitic species such asthe members of the Santalaceae. Topsoil was oneof the main sources of propagules for many of theground cover and shrub species, and these propa-gules often fail to survive prolonged topsoil hand-ling (Clark 1975; Brooks 1987). In addition, thespecies composition of the topsoil seed bank maybe considerably different from that of the above-ground plants (Bell etal. 1990).

Our data indicate that differences betweendunes in widely separated locations of Myall LakesNational Park are no greater than those betweenunmined and (old) mined areas (Fig. 7), so an at-tempt to ensure authenticity of vegetation cover byreplacing topsoil in its area of origin was possiblymisguided in this case. Immediate transport andreplacement of topsoil has been practised for manyyears in the Western Australian bauxite miningareas and elsewhere (Ward et al. 1990), and shrubmulching is becoming a common practice (Bellet al. 1990). Both ofthese techniques recognize thefact that the disturbance due to mining is suf-ficiently great that subtle differences caused byrelocation of species are relatively insignificant,while there are distinct advantages in utilizing thetopsoil and above-ground seeds while plant propa-gules are still viable.

CONCLUSION

During the first 15 years after sand mining com-menced, the vegetation on the Bridge Hill dune inMyall Lakes National Park developed a decreasingsimilarity to the vegetation previously there, and

maintained a distinctiveness in comparison withthe vegetation on the other dunes in the area. Therevegetated dune shows increasing species richnessand diversity, and extensive colonization by intro-duced species.

The goal of complete restoration (i.e. a com-munity reconstructed exactly as it was beforemining) is probably unrealistic in general (Belletal. 1990), and is almost certainly so at MyallLakes (Carolin 1970), although future vegetationdevelopment may eliminate some of the differ-ences in species composition observed in our study.However, the value of active attempts at vegetationrestoration as an exercise in applied ecology cannotbe over-emphasized (Jordan etal. 1987).

In particular, understanding the relationship be-tween the human-activated recovery process andnatural successional patterns could be very import-ant (Mclntosh 1980). In the context of the ecologi-cal behaviour of the sclerophyll forests of Australia,the relationship between the temporal patterns fol-lowing mining and those following endogenousdisturbances such as fire may be especially reveal-ing (Clark 1975; Thatcher & Westman 1975; Belletal. 1990; Fox 1990). To date, the vegetation onthe mined area at Bridge Hill has not been burnt,but its response when this does eventually happenshould be worth recording.

ACKNOWLEDGEMENTS

We are indebted to the dedication of Jonas Ruppfor data entry and field assistance, to Bob Outhredand Carina Clarke for help with the early years ofthis study, to the technical staff of the Departmentof Applied Biology for logistic support, to BarbaraAlmond for help with figure preparation, to thestaff of Mineral Deposits Ltd for their co-oper-ation, and to more than 200 second year students ofUTS for their competent field assistance. This pro-ject was conducted with the permission of theNational Parks & Wildlife Service of New SouthWales, and was financially supported by a grantfrom the University of Technology, Sydney. TonyAuld, Peter Clarke, Barry and Marilyn Fox, DavidKeith and Peter Myerscough commented on anearlier draft of the manuscript.

REFERENCES

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Belbin L. (1989) PATN: Pattern Analysis Package Technical Refer-ence. CSIRO, Canberra.

Bell D. T., Vlahos S. & Bellairs S. M. (1990) Seed ecology inrelation to reclamation: Lessons from mined lands in WesternAustralia. Proc. Ecol. Soc. Aust. 16, 531-5.

Bloom S. A. (1980) Multivariate quantification of community re-covery. In: The Recovery Process in Damaged Ecosystems (ed.]. Cairns) pp. 141-51. Ann Arbor Science, Ann Arbor.

Brockhoff ]. O. & Allaway W. G. (1989) Vesicular-arbuscularmycorrhizal fungi in natural vegetation and sand-mineddunes at Bridge Hill. New South Wales. Wetlands (Aust.) 8,47-54.

Brooks D. (1987) The use of native plant seed by the mineral sandsindustry. In: Germination of Australian Native Plant Seed (ed.P. J. Langkamp) pp. 115-20. Inkata Press, Melbourne.

Carolin R. C. (1970) Myall Lakes: An ancient and modern monu-ment. Proc. Ecol Soc. Aust. 5, 123-9.

Chambers J. C. (1983) Measuring species diversity on revegetatedsurface mines: An evaluation of techniques. USDA Eor. Serv.Res. Paper INT-322.

Clark S. S. (1975) The effect of sand mining on coastal heath veg-etation in New South Wales. Proc. Ecol Soc. Aust. 9, 1-16.

Faith D. P., Minchin P. R. & Belbin L. (1987) Compositional dis-similarity as a robust measure of ecological distances: Atheoretical model and computer simulations. Vegetatio 69,57-68.

Fox B. J. (1990) Two hundred years of disturbance: How has itaided our understanding of succession in Australia? Proc.Ecol. Soc. Aust. 16, 521-9.

Fox B. J. & Fox M. D. (1978) Recolonization of coastal heath byPseudomys novaehollandiae (Muridae) following sand mining.Aust. J. Ecol. 3, 447-65.

Fox B. J. & Fox M. D. (1984) Small-mammal recolonization ofopen-forest following sand-mining. Aust. J. Ecol 9, 241-52.

Fox M. D. (1988) The ecological status of alien plant species. In:Weeds on Public Land: An Action Plan for Today (ed. R. G.Richardson) pp. 42-5. Weed Science Soc. Vic, Melbourne.

Gilpin A. (1990) An Australian Dictionary of Environment andPlanning. Oxford University Press, Melbourne.

Haering R. & Fox B. J. (1987) Short-term coexistence and long-term competitive displacement of two dominant species ofIridomyrmex: The successional response of ants to regener-ating habitats. J. Anim. Ecol 56, 495-507.

Hill M. O. (1979) TWINSPAN: A Eortran Program for ArrangingMultivariate Data in an Ordered Two-way Table by Classifi-cation of the Individuals and Attributes. Cornell University,New York.

Hill M. O., Bunce R. G. H. & Shaw M. W. (1975) Indicator speciesanalysis, a divisive polythetic method of classification, and itsapplication to a survey of native pinewoods in Scotland.J. Ecol. 63, 597-613.

Inouye D. W. (1988) Variation in undisturbed plant and animalpopulations and its implications for studies of recoveringecosystems. In: Rehabilitating Damaged Ecosystems, Vol. II(ed. J. Cairns) pp. 39-50. CRC Press, Boca Raton.

Jacobs S. W. L. & Pickard J. (1981) Plants of New South Wales:A Census of the Cycads, Conifers and Angiosperms. NationalHerbarium of NSW, Sydney.

Jasper D. A., Robson A. D. & Abbott L. K. (1987) The effect ofsurface mining on the infectivity of vesicular-arbuscularmycorrhizal fungi. Aust. J. Bot. 35, 641-52.

Jordan W. R., Gilpin M. E. & Aber J. D. (1987) Restoration Ecology:A Synthetic Approach to Ecological Research. Cambridge Uni-versity Press, Cambridge.

Marrs R. H. & Gough M. W. (1989) Soil fertility: A potential prob-lem for habitat reconstruction. In: Biological Habitat Re-construction (ed. G. P. Buckley) pp. 29-44. Belhaven Press,London.

Mclntosh R. P. (1980) The relationship between succession andthe recovery process in ecosystems. In: The Recovery Processin Damaged Ecosystems (ed. J. Cairns) pp. 11-62. Ann ArborScience, Ann Arbor.

Myerscough P. J. & Carolin R. C. (1986) The vegetation of theFurunderee sand mass, headlands and previous islands in theMyall Lakes area. New South Wales. Cunninghamia 1, 399-466.

Nicholls A. O. (1991) Examples of the use of generalised linearmodels in analysis of survey data for conservation evaluation.In: Nature Conservation: Cost Effective Biological Surveys andData Analysis (eds C. R. Margules and M. P. Austin) pp. 54-63. CSIRO, Canberra.

Outhred R. K. (1983) Semi-quantitative sampling in vegetationsurvey. In: Survey Methods for Nature Conservation (edsK. Myers, C. R. Margules and I. Musto) pp. 87-100. CSIRO,Canberra.

Panetta F. D. & Groves R. H. (1990) Weed management and re-vegetation programmes. Proc. Ecol Soc. Aust. 16, 537-43.

Pickett S. T. A. (1989) Space-for-time substitution as an alternativeto long-term studies. In: Long-term Studtes in Ecology (ed.G. E. Likens) pp. 110-35. Springer-Verlag, New York.

Specht R. L. (1975) The effect of fertilizers on sclerophyll (heath)vegetation: The problems of revegetation after sand mining.Search 6,459-61.

Stewart-Oaten A., Murdoch W. W. & Parker K. R. (1986) Environ-mental impact assessment: 'Pseudoreplication' in time?Ecology 67, 929-40.

Thatcher A. C. & Westman W. E. (1975) Succession followingmining on high dunes of coastal southeast Queensland. Proc.Ecol. Soc. Aust. 5, 17-33.

Thom B. G., Bowman G. M. & Roy P. S. (1981) Late Quaternaryevolution of coastal and sand barriers. Port Stephens-MyallLakes area, central New South Wales, Australia, Quat. Res.15, 345-64.

Twigg L. E. & Fox B. J. (1991) Recolonization of regeneratingopen forest by terrestrial lizards following sand mining.Aust. J. Ecol 16, 137-48.

Twigg L. E., Fox B. J. & Luo J. (1989) The modified primarysuccession following sand mining: A validation of the use ofchronosequence analysis. Aust. J. Ecol. 14, 441-7.

Ward S. C, Koch J. M. & Nichols O. G. (1990) Bauxite minerehabilitation in the Darling Range, Western Australia. Proc.Ecol. Soc. Aust. 16, 557-65.

Wilkinson L. {\9'il)SYSTAT: The System for Statistics. Systatlnc,Evanston.


APPENDIX I. Average importance score for each species in the various unmined areas and at various timespost mining (PM) in the mined area in Myall Lakes National Park, and the results ofthe non-parametricstatistical comparisons

Family/species

No, quadrats

PteridophytesBlechnaceae

Blechnum indicumCyatheaceae

Culcita dubiaDennstaedtiaceae

Pteridium esculentumSchizaeaceae

Schizaea bifidaGymnosperms

ZamiaceaeMacrozamia communis

MonocotyledonsArecaceae

Livistona australisCyperaceae

Gahnia clarkeiLepidosperma longitudinaleIsolepis nodosa

HaemodoraceaeHaemodorum corymbosum

IridaceaePatersonia fragilisPatersonia glabrataPatersonia longifoliaPatersonia sericea

LiliaceaeBulbine bulbosaDianella caeruleaDianella laevisTricoryne elatior

LomandraceaeLomandra micranthaLomandra longifolia

OrchidaceaeAcianthus exsertusCaladenia catenataEriochilus cucullatusPterostylis nana

PoaceaeAndropogon virginicus^Axonopus affinis^Digitaria didactylaDigitaria diminutaEntolasia marginataEmolasia strictaEragrostis cilianensis'iImperata cylindricaPaspalum dilatatum'iPaspalum orbicularePoa sieberianaSorghum sp.t

Originaldune

41

0.0

0.0

6.0

4.3

5.8

0.0

0.00.00.0

0.0

0.30.01.90.0

0.06.40.00.0

0.26.0

3.10,00.00.3

0.00,00,00,00,10,30.05,40,00.01,30,0

UnminedAdjacent

dune

35

0.1

0.3

8,2

0.7

6.7

0.1

0.20.10.1

0,2

0,00,70,00,0

0,15,00,10,1

0,56,1

0,60,00.00,3

0,00.00,00,10,10,00.45,10,00.60.00.0

areasKataway

dune

8

0,0

0,0

10,4

2,6

0,0

0,0

0,00,00,0

0,0

0,06,00,00,0

0,07,40,00,0

0,05.5

8,90,01.50,0

0,00,00,00,00.00,01.65.60.00,00,00.0

Powerpole

2

0,0

0,0

10,5

6,0

3,5

0,0

0,00,00.0

0,0

0,00,00,00.0

0,08,50.00,0

0,05.5

1,00,00,00,0

0,00.00,00,00,00,03,54,00.00,00,00,0

Mined areas2-6

yearsPM

17

0,0

0,0

0,6

0.0

4.7

0,0

0,00,00.0

0,0

0,50,41,50,7

0,22,20,00,0

0,05,3

0,00,00,00,0

0,50,00,40,20,00.02,20,10,10.10,00,1

7-10yearsPM

10

0,0

0,0

0,0

0.0

3,2

0.0

0,00,00,0

0,0

0,00,80,01,1

0,02,00,00,0

0,05,1

0,00,00,00,0

2,72,30,00,00,00.03,10.11.02.80.00,1

11-15yearsPM

12

0,0

0,0

0,8

0,0

3,1

0,0

0,01,60,8

0,0

0,30,60,00.3

0.01,80,02.5

0,05,8

0,00,30.00.0

2,80,50.00,00,02,57.81,60,02,60,00,0

Statistical analysesAdjacent

Original vs Withinvs mined mined mined

** **

** **

** **

**

* •

• * *

* * * *

* *

* *

* * * * * *

* * * * *«

* * • •

* * * * * *

* * * * * *

« «


APPENDIX I. Continued

Family/species

Sporobolus africanus^Themeda australisZoysia macrantha

RestionaceaeLeptocarpus tenaxRestio tetraphyllus

SmilacaceaeS mi lax glyciphylla

XanthorrhoeaceaeXanthorrhoea australis

DicotyledonsAizoaceae

Carpobrotus glaucescensApiaceae

Actinotus helianthiPlatysace ericoidesPlatysace lanceolataPlatysace linearifoliaTrachymene incisaXanthosia pilosa

AraliaceaeAstrotricha longifoliaPolyseias sambueifolia

AsteraceaeBidens pilosa^Braehyeome sp.Cassinia aculeataChrysanthemoides monilifera^Conyza bonariensis'tConyza canadensis^Erechtites valerianifoliaGnaphalium candidissimum^Hypoehoeris radieata^Olearia viscidulaSeneeio lautusSeneeio Imearifohus

BignoniaceaePandorea pandorana

CasuannaceaeCasuarina torulosa

ChloanthaceaeChloanthes stoechadts

DilleniaceaeAdrastaea salicifoliaHibbertia asperaHibbertia dentataHibbertia linearisHibbertia obtusifoliaHibbertia scandens

EpacridaceaeAstroloma pinifoliumBrachyloma daphnoidesEpacris mierophyllaEpacris obtusifoliaEpacris pulchella

Originaldune

0.02.40.0

0.00.0

0.6

0.1

0.0

0.33.00.70.05.50.0

1.02.8

0.00.60.00.00.00.00.60.00.00.00.20.3

1.0

0.5

0.0

0.00.00.00.30.00.0

0.50.00.20.11.2

UnminedAdjacent

dune

0.06.10.0

1.41.0

0.1

2.1

0.0

0.72.90.90.01.80.4

0.72.1

0.00.00.10.10.10.80.30.00.20.00.50.1

0.5

0.0

0.1

0.20.10.13.00.00.3

0.01.20.00.00.3

areasKataway

dune

0.02.10.0

0.00.0

0.0

0.0

0.0

0.00.0

10.50.00.00.0

0.90.0

0.00.00.00.00.00.00.00.00.00.00.00.0

0.0

0.0

1.3

5.90.00.00.00.00.0

0.00.00.00.00.0

Powerpole

0.03.00.0

0.00.0

0.0

1.5

0.0

0.52.50.00.06.00.0

0.00.0

0.00.00.00.00.00.00.00.00.00.00.00.0

1.0

0.0

0.0

9.00.00.00.00.00.0

0.00.00.00.00.0

Mined areas2-6

yearsPM

0.00.50.2

0.20.0

0.0

0.0

0.0

1.17.11.60.53.90.4

1.70.0

0.00.00.20.02.25.20.00.22.90.00.50.0

0.0

0.0

0.0

2.60.00.02.50.20.0

0.00.30.00.00.1

7-10yearsPM

0.50.80.0

0.01.8

0.0

0.0

0.7

2.14.92.10.00.00.0

0.80.0

0.10.01.90.00.88.30.00.08.00.30.00.0

0.0

0.0

0.0

2.30.00.04.30.00.0

0.02.60.00.00.0

11-15yearsPM

0.33.30.0

0.90.1

0.0

0.0

1.7

0.55.50.50.00.00.0

1.20.0

0.00.04.30.02.24.80.00.06.70.00.00.0

0.0

0.0

0.0

4.60.00.06.90.60.0

0.00.80.00.00.1



* • * *

* * * *

**

* * * * * *

* *

* * * *

* * * *

it*

* * * * * *

* * * *

* * * *

* * * • * *

• * . **

* *

* * * *

* *

* * * *

R E V E G E T A T I O N OF M I N E D S A N D D U N E S 253


Family/species

Leucopogon ericoidesLeucopogon lanceolatusLissanthe strigosaMelichrus procumbensMonotoca ellipticaMonotoca scopariaSprengelia incarnataStyphelia viridis

EuphorbiaceaeAmperea xiphocladaBreynia oblongifoliaOrnalanthus populifoliusPoranthera erictfoliaPoranthera microphyllaRicinocarpos pinifolius

FabaceaeAotus ericoidesBossiaea ensataBossiaea heterophyllaDesmodium brachypodumDillwynia glaberrimaDillzvynia retortaGlyeme clandestinaGompholobium grandiflorumGompholobium latifoliumHardenbergia violaceaHovea linearisIndigofera australisKennedia rubicundaOxylobium ilicifoliutnPhyllota phylicoidesPlatylobium formosum

GoodeniaceaeDampiera strictaGoodenia bellidifoliaGoodenia heterophyllaScaevola aemula

HaloragaceaeGonocarpus micranthusGonocarpus teucrioides

LauraceaeCassytha spp.Endiandra sieberi

MalvaceaeHowittia trilocularis

MimosaceaeAcacia elongataAcacia longifoliaAcacia suaveolensAcacia terminalisAcacia ulicifolia

MyoporaceaeMyoporum insulare

MyrtaceaeAngophora costata

Originaldune

1.34.40.10.55.50.00.10.6

0.00.00.00.20.06.0

2.95.04.60.31.81.60.10.95.65.21.10.70.30.03.04.7

0.00.30.10.1

0.06.2

0.64.6

0.0

0.04.96.51.24.9

0.3

6.0

UnminedAdjacent

dune

2.84.70.10.94.10.30.02.2

0.20.30.10.31.42.3

0.12.67.02.30.01.81.11.52.94.40.60.31.10.47.31.4

0.10.00.00.0

0.08.0

0.11.5

0.1

0.14.24.80.84.3

0.0

5.1

areasKataway

dune

3.65.00.00.05.00.00.05.6

0.00.00.00.00.04.3

0.01.15.00.00.09.00.00.04.07.40,10.00.00.02.50.0

0.00.00.00.0

0.07.8

1.30.0

0.0

0.01.84.00.09.8

0.0

4.3

Powerpole

5.00.00.00.00.00.00.00.0

0.00.00.00.00.07.5

0.09.07.00.00.00.00.00.00.00.00.00.00.00.07.50.5

0.00.00.00.0

0.03.0

0.01.0

0.0

0.01.53.50.53.0

0.0

5.0

Mined areas2-6

yearsPM

1.81.80.00.18.00.10.01.1

0.00.00.00.21.00.5

0.05.73.61.50.05.90.02.63.04,70.81.51.10.08.23.4

0.00,00.00.0

0.47,9

0,90,0

0,0

0.07,15,13.63.7

0.0

5.9

7-10yearsPM

2.30.70.00.05.60.00,00.8

0,00,00,10.01.50.9

0.04.85.11.00.03,61,53,11.25.50.11.81,40.04,42.3

0,00.00,00.0

0.08.3

1.20.0

0,0

0.07.24.62.56.1

0.0

4.6

11-15yearsPM

6.01.50.90.06,00,00,02.4

0,00,70,10,00,00,8

0.24.35,41.80,05.60,63,82,93,30.00.93.00.04.52.5

0.00.00.00.7

0.06.9

0.00.0

0.0

0.06.56.13.55.3

0.0

4,6



• * * *

* * * *

* *

* * * *

* * * *

- * *

* * * *

*i<

* * * *

* *

* * * *

irir

**

* * + *

* * * *



Family/species

Eucalyptus gummiferaEucalyptus pilularisEucalyptus robustaLeptospermum attenuatumLeptospermum flavescensLeptospermum laevigatumMelaleuca armillaris

OlacaceaeOlax stricta

PittosporaceaeBillardiera scandens

PolygalaceaeComesperma ericmum

ProteaceaeBanksia aemulaBanksia ericifoliaBanksia integrifoliaBanksia serrataConospermum taxifoltumHakea propinquaIsopogon anemonifotiusPersoonia lanceolataPersoonia levisPersoonia linearisXylomelum pyriforme

RanunculaceaeClematis aristata

RubiaceaePomax umbellata

RutaceaeBoronia pinnataCorrea reflexaEriostemon australasiusZieria laevigata

SantalaceaeChoretrum candolleiExocarpos cupressiformisLeptomerta acida

SapindaceaeDodonaea triquetra

ThymeleaceaePimelea linifolia

TremandraceaeTetratheca ericifoliaTetratheca thymifolia

VerbenaceaeLantana camara^

VitaceaeCissus antartica

MiscellaneousGrass 1Unknown 1Unknown 2

Originaldune

0.06.60.00.30.10.00.2

0.0

3.7

0.0

3.30.00.23.92.80.00.20.76.60.15.1

0.0

4.5

0.06.20.00.0

2.40.03.6

0.0

0.5

0.74.3

0.0

0.0

0.10.10.2

UnminedAdjacent

dune

0.13.80.20.50.90.00.0

0.1

1.7

0.1

0.00.00.35.20.60.00.00.92.50.90.8

0.3

5.5

0.92.50.30.0

0.00.01.4

0.7

0.1

2.42.9

0.0

0.0

0.00.00.0

areasKataway

dune

0.05.00.00.00.00.00.0

0.0

1.8

0.0

0.00.00.05.40.00.00.00.03.80.00.0

0.0

4.9

0.02.60.00.0

0.00.03.9

0.0

1.8

0.05.8

0.0

0.0

0.00.00.0

Powerpole

0.03.00.00.00.00.00.0

0.0

0.0

0.0

0.00.00.04.02.00.00.00.00.06.01.0

0.0

8.5

0.03.00.00.0

0.00.03.5

1.0

0.0

0.05.0

0.0

0.0

0.00.00.0

Mined areas2-6

yearsPM

0.03.50.00.00.20.00.0

0.0

0.2

0.0

0.00.20.13.51.10.00.00.52.50.50.1

0.0

7.2

0.01.10.00.0

0.40.40.7

0.5

1.8

0.50.4

0.0

0.0

0.00.00.0

7-10yearsPM

0.03.00.00.00.00.60.0

0.0

0.5

0.0

0.00.00.53.61.70.40.00.12.70.00.0

0.0

7.7

0.02.40.00.0

0.00.00.0

2.5

0.7

2.10.0

0.3

0.0

0.00.00.0

11-15yearsPM

0.44.80.00.20.01.50.3

0.0

0.9

0.0

0.00.00.23.00.10.00.04.30.60.10.1

0.0

4.8

0.02.70.01.0

0.00.00.3

3.9

0.9

3.20.9

0.2

0.4

0.00.00.0

Statistical analyses

Originalvs mined

**

iiii

* *

* *

* *

A *

* *

* *

iiit

**

Adjacentvs Within

mined mined

***ic * *

it*

* •

*.*

* *

* *

* *

* * * *

* *

* *

**P<0.05.t Introduced species.Nomenclature follows Myerscough and Carolin (1986), plus Jacobs and Pickard (1981) for other species.

temporal trends in plant species composition on mined sand...

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