Shrubland ambivalent in its syndromes of dissemination by animals: a base-rich littoral site at Fitzgerald River National Park, southwestern Australia

@peterslingsby @arthur_chapman

Under mesic, temperate climates in Australia and southern Africa, vegetation tends to contain either myrmecochorous plants (https://en.wikipedia.org/wiki/Myrmecochory and https://web.archive.org/web/20110721113717/http://ecology.science.unideb.hu/ConsEcolGroup/Pdf/Lengyel%20et%20al%202010%20(MyrmecochoryReview).pdf and https://www.semanticscholar.org/paper/Myrmecochorous-plants-in-Australia-and-their-by-Berg/7bb772f70dcc6078c7fb652ef7614af961a4e9f5), disseminated by ants, or endozoochorous plants, disseminated by birds.

Vegetation types emphasising myrmecochorous plants include kwongan (https://en.wikipedia.org/wiki/Kwongan), wallum (https://en.wikipedia.org/wiki/Wallum), heathland, and mallee-heath (https://en.wikipedia.org/wiki/Mallee_Woodlands_and_Shrublands) in Australia, and fynbos (https://en.wikipedia.org/wiki/Fynbos) in South Africa.

Vegetation types emphasising endozoochorous plants include vine-thicket (https://www.anbg.gov.au/photo/vegetation/rainforesst-vine-thickets.html) and rainforest (in the loose sense) in Australia, and strandveld (https://en.wikipedia.org/wiki/Cape_Flats_Dune_Strandveld), various forms of thicket (https://en.wikipedia.org/wiki/Albany_thickets), and southern afrotemperate forest (https://en.wikipedia.org/wiki/Southern_Afrotemperate_Forest) in South Africa.

In this Post I document a plant community in Australia that happens to be exactly intermediate, in the sense that the two syndromes of dissemination are equally balanced.

The following may explain how I came to focus on the shrubland in question.

Vine-thicket is latitudinally widespread in Australia, but is everywhere restricted to small patches.

This restriction is because vine-thicket depends on a combination of

  • relatively nutrient-rich soils, and
  • relative freedom from wildfires by virtue of slight topographic barriers.

The southwestern region of Western Australia (https://www.bibbulmuntrack.org.au/media/files/jewel_of_the_australian_continent_1.pdf) lacks vine-thicket, despite the fact that such vegetation occurs at similar latitudes in eastern Australia. This seems to be because the land is so flat, and intense wildfires so extensive, that not a single hectare of this vast area - apart from saline or semi-saline sites - of nearly 50 million hectares has been exempt from the tyranny of a regime that perpetuates flammable vegetation types: kwongan, mallee-heath, mallee, and eucalypt forest/woodland.

In the late seventies I became curious as to what kind of shrubland might occur in the situations most edaphically suited to vine-thicket in southwestern Western Australia, i.e. situated at the very threshold of eligibility.

The following is the composition of a particular plant community that - I suspect - would be vine-thicket were the surrounding conditions slightly more protective. It is one of the two study sites reported in https://www.semanticscholar.org/paper/Convergence-of-myrmecochory-in-mediterranean-and-Milewski-Bond/5cc228e53f72f9beabef44e586e84320bbb1fb3f, and happens nearly to correspond to the location of https://www.inaturalist.org/observations/92633287.

The study site is just southeast of Culham Inlet (https://www.alamy.com/stock-photo-culham-inlet-fitzgerald-river-np-wa-australia-75930034.html and https://en.wikipedia.org/wiki/Culham_Inlet) and adjacent to the southeastern corner of the unusually hilly Fitzgerald River National Park (https://en.wikipedia.org/wiki/West_Mount_Barren and https://en.wikipedia.org/wiki/Fitzgerald_River_National_Park).

The study site has since been spoiled by roadworks (https://www.kalminer.com.au/news/kalgoorlie-miner/culham-inlet-causeway-an-important-step-for-hopetoun-ng-b881267020z).

The soil in this site was:

  • base-rich (https://en.wikipedia.org/wiki/Base-richness) because it combined calcareous littoral sand with alluvium, the site perhaps being somewhat topographically protected from wildfires, and
  • relatively rich in phosphorus for southwestern Western Australia, but also rather sodic because of proximity to a semi-saline inlet in a landscape devoid of perennial streams.

My floristic list is based on six visits made between 1978 and 1983, at various times of year. * indicates non-indigenous species, FF indicates species with fleshy fruits, E indicates species with elaiosomes attractive to ants, and FF/E indicates species with diaspores of intermediate structure such as fleshy fruits so small that they are as attractive to ants as to birds.

The number of myrmecochorous species is similar to that of bird-disseminated species, because elaiosomes/small arils occur on the seeds of more than ten of the species and some of the fleshy fruits are smaller and duller-hued than those typically attractive to birds.

The commonest of the myrmecochorous species is Acacia rostellifera in stunted form, which forms clumped (clonal) shrubs about 1.2 meters high.

There are up to 15 indigenous species bearing fleshy fruits in this plant community, which is an unusually large number for southwestern Australia. This would somewhat emulate vine-thicket were it not for the fact that many of the present species have halophytic affinities rather than the affinities with rainforests expected in vine-thicket.

The commonest of the non-halophytic species with fleshy fruits is Billardiera heterophylla. This is fairly common in the site and, although liane-like, effectively forms domed shrubs with dense crowns, one meter high.

The overall result:
In this plant community, the approximately 30 species disseminated by animals are about evenly balanced between myrmecochorous and endozoochorous, with ambivalent diaspores in members of Amaranthaceae, Epacridaceae, Lauraceae, Mimosaceae and Polygonaceae.

The following list is arranged in alphabetical order by families/genera/species.

AIZOACEAE
Carpobrotus virescens FF https://www.inaturalist.org/taxa/511201-Carpobrotus-virescens
Tetragonia implexicoma FF https://www.inaturalist.org/taxa/407885-Tetragonia-implexicoma and https://www.inaturalist.org/observations/66940816

AMARANTHACEAE
Atriplex paludosa ssp. baudinii https://www.inaturalist.org/taxa/502243-Atriplex-paludosa
Chenopodium baccatum FF https://www.inaturalist.org/taxa/511299-Chenopodium-baccatum and https://www.inaturalist.org/observations/73296454
Chenopodium wilsonii FF https://www.inaturalist.org/taxa/1047741-Chenopodium-wilsonii and https://www.inaturalist.org/observations/106408468
Enchylaena tomentosa small FF https://www.inaturalist.org/taxa/369256-Enchylaena-tomentosa
Suaeda australis https://www.inaturalist.org/taxa/353651-Suaeda-australis
Threlkeldia diffusa FF/E https://www.inaturalist.org/taxa/481549-Threlkeldia-diffusa and https://www.inaturalist.org/observations/12376169 and https://www.inaturalist.org/observations/37631472

APIACEAE
Daucus glochidiatus https://www.inaturalist.org/taxa/210346-Daucus-glochidiatus
Trachymene pilosa https://www.inaturalist.org/taxa/511206-Trachymene-pilosa

ASPARAGACEAE
*Asparagus asparagoides FF https://www.inaturalist.org/taxa/64107-Asparagus-asparagoides
Thysanotus patersonii E? https://www.inaturalist.org/taxa/323937-Thysanotus-patersonii and https://digital.library.adelaide.edu.au/dspace/bitstream/2440/59350/8/02chapters1-4.pdf

ASPHODELACEAE
Dianella revoluta FF https://www.inaturalist.org/taxa/210175-Dianella-revoluta and https://www.inaturalist.org/observations/102860491

ASTERACEAE
Olearia axillaris https://www.inaturalist.org/taxa/428475-Olearia-axillaris
Senecio lautus ssp. dissectifolius https://www.inaturalist.org/taxa/323168-Senecio-lautus
Sonchus oleraceus https://www.inaturalist.org/taxa/53294-Sonchus-oleraceus

BRASSICACEAE
*Brassica tournefortii https://www.inaturalist.org/taxa/75870-Brassica-tournefortii

CRASSULACEAE
Crassula colorata https://www.inaturalist.org/taxa/380776-Crassula-colorata

ERICACEAE
Acrotriche cordata FF/E https://www.inaturalist.org/taxa/323995-Acrotriche-cordata and https://www.inaturalist.org/observations/103359464

FABACEAE
Pultenaea barbata E https://www.inaturalist.org/observations/105544808

GERANIACEAE
Pelargonium littorale https://www.inaturalist.org/taxa/735460-Pelargonium-littorale

GOODENIACEAE
Scaevola crassifolia E? https://www.inaturalist.org/taxa/481347-Scaevola-crassifolia

LAMIACEAE
Westringia dampieri E https://www.inaturalist.org/taxa/468632-Westringia-dampieri

LAURACEAE
Cassytha melantha FF https://www.inaturalist.org/taxa/733735-Cassytha-melantha and https://www.inaturalist.org/observations/71931219
Cassytha filiformis FF/E https://www.inaturalist.org/observations/60270940

MALVACEAE
Guichenotia ledifolia E https://www.inaturalist.org/taxa/545382-Guichenotia-ledifolia
Lasiopetalum discolor E https://www.inaturalist.org/taxa/565115-Lasiopetalum-discolor

MIMOSACEAE
Acacia cochlearis E https://www.inaturalist.org/taxa/53345-Acacia-cochlearis
Acacia cyclops large aril functionally similar to fleshy fruit https://www.inaturalist.org/taxa/75249-Acacia-cyclops
Acacia rostellifera E https://www.inaturalist.org/taxa/927752-Acacia-rostellifera

MYRTACEAE
Eucalyptus angulosa https://www.inaturalist.org/taxa/208143-Eucalyptus-angulosa
Melaleuca lanceolata https://www.inaturalist.org/taxa/465912-Melaleuca-lanceolata
Melaleuca quadrifida https://www.inaturalist.org/taxa/589723-Melaleuca-quadrifida

OXALIDACEAE
Oxalis corniculata https://www.inaturalist.org/taxa/53168-Oxalis-corniculata

PHYLLANTHACEAE
Phyllanthus calycinus E? https://www.inaturalist.org/taxa/145401-Phyllanthus-calycinus

PITTOSPORACEAE
Billardiera heterophylla FF https://www.inaturalist.org/taxa/75769-Billardiera-heterophylla

PLANTAGINACEAE
Plantago varia https://www.inaturalist.org/taxa/404986-Plantago-varia

POACEAE
*Avena sativa https://www.inaturalist.org/taxa/57156-Avena-sativa
Austrostipa variabilis https://en.wikipedia.org/wiki/Austrostipa_variabilis

POLYGONACEAE
Muehlenbeckia adpressa FF/E https://www.inaturalist.org/taxa/323838-Muehlenbeckia-adpressa

PORTULACACEAE
Calandrinia calyptrata https://www.inaturalist.org/taxa/555999-Calandrinia-calyptrata

PRIMULACEAE
*Lysimachia arvensis https://www.inaturalist.org/taxa/791928-Lysimachia-arvensis

RANUNCULACEAE
Clematis pubescens https://www.inaturalist.org/taxa/145426-Clematis-pubescens
Clematis linearifolia https://www.inaturalist.org/taxa/896461-Clematis-linearifolia

RHAMNACEAE
Spyridium globulosum E https://www.inaturalist.org/taxa/803893-Spyridium-globulosum

RUBIACEAE
*Galium murale https://www.inaturalist.org/taxa/59005-Galium-murale

RUTACEAE
Boronia tetrandra E https://www.inaturalist.org/taxa/1115266-Boronia-tetrandra

SANTALACEAE
Santalum spicatum (FF) https://www.inaturalist.org/taxa/793376-Santalum-spicatum

SOLANACEAE
Solanum symonii FF https://www.inaturalist.org/taxa/947933-Solanum-symonii and http://www.flora.sa.gov.au/efsa/lucid/Solanaceae/Solanum%20species/key/Australian%20Solanum%20species/Media/Html/Solanum_symonii.htm

THYMELAEACEAE
Pimelea clavata? E https://www.inaturalist.org/taxa/841593-Pimelea-clavata
Pimelea ferruginea E https://www.inaturalist.org/observations/92633287

ZYGOPHYLLACEAE
Roepera apiculata E https://www.inaturalist.org/taxa/778949-Roepera-apiculata

Posted on Φεβρουάριος 28, 2022 0459 ΠΜ by milewski milewski

Σχόλια

The flora of Fitzgerald River National Park is rich (1748 species, https://www.awe.gov.au/parks-heritage/heritage/places/national/fitzgerald-river-national-park#:~:text=The%20national%20park%20supports%20a,within%20the%20park%27s%20297%2C244%20hectares.), but contains remarkably few lianes: Billardiera spp., Convolvulus erubescens, Cassytha spp., Glycine clandestina, Kennedia nigricans, Hardenbergia comptoniana, Comesperma volubile, C. integerrima, Muehlenbeckia adpressa, and Clematis spp. It is noteworthy that at least six of these occur in the site described above.

Αναρτήθηκε από milewski περίπου 2 χρόνια πριν

I recorded the following bird species in this site:
Cracticus torquatus
Pomatostomus supercilosus
Phylidonyris novaehollandiae
Lichenostomus virescens
Lichmera indistincta
Colluricincla harmonica
Zosterops lateralis
Malurus pulchellus
Stipiturus malachurus
Sericornis frontalis
Emblema oculata

Αναρτήθηκε από milewski περίπου 2 χρόνια πριν

Jerome Patrick Bull 2006

The ecological significance of frugivorous animals as seed vectors of fleshy-fruited plants in High diversity ecosystems of south-western Australia
https://api.research-repository.uwa.edu.au/ws/portalfiles/portal/48829500/Bull_Jerome_Patrick_2006_compressed.pdf

Αναρτήθηκε από milewski σχεδόν 2 χρόνια πριν

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