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1
Moseby, K. E., R. Brandle e M. Adams. "Distribution, habitat and conservation status of the rare dusky hopping-mouse, Notomys fuscus (Rodentia : Muridae)". Wildlife Research 26, n. 4 (1999): 479. http://dx.doi.org/10.1071/wr97061.
Testo completoAbstract (sommario):
The distribution, habitat and conservation status of Notomys fuscus were determined by collating past records of the species and conducting field investigations covering areas of historical distribution and similar habitats. Detailed population sampling was carried out in two geographically distinct locations where populations appeared to be extant. Evidence of N. fuscus was found throughout the Strzelecki Desert east and south of the Strzelecki Creek in South Australia and in an isolated group of dunes south-east of the Diamantina River in south-west Queensland. Populations were located in a variety of sand dune habitats (excepting those dominated by Triodia) throughout these areas, implying that the species is a habitat-generalist with a preference for a sandy substrate. Eight floristic groups were identified from the 66 sites sampled, three of which supported N. fuscus populations. These ranged from extremely degraded dune and sand plain systems in the southern Strzelecki Desert, supporting mostly ephemeral plants, to well-vegetated dunes covered by sandhill canegrass,Zygochloa paradoxa, in south-west Queensland. However, the results suggest that the presence of consolidated dunes and perennial vegetation are important for the maintenance of stable populations. Relatively dense populations of N. fuscus were recorded only in the vicinity of major drainage systems. It is hypothesised that the higher nutrient status of the soils surrounding such systems may be an important factor affecting the distribution of N. fuscus. The study reaffirmed the species’ decline since European settlement of Australia, and recommends that the present vulnerable status of the species (IUCN Species Survival Commission (SSC) Rodent Specialist Group) be maintained.
2
Liu, Zhengyao, Zhibao Dong e Xujia Cui. "Morphometry of lunette dunes in the Tirari Desert, South Australia". Open Geosciences 10, n. 1 (14 settembre 2018): 452–60. http://dx.doi.org/10.1515/geo-2018-0035.
Testo completoAbstract (sommario):
Abstract Morphometry and formation processes are key research problems in the study of aeolian sandy landforms. Based on morphometric parameters inferred from satellite images and the calculation of the drift potential (DP), we examined general characteristics of lunette dunes in the Tirari Desert, South Australia, along with their morphometry and formation processes to determine how this landform type initially formed and its relationship to surrounding linear dune distribution. Results show that the morphometric parameters of lunette dunes and connective lake systems exhibit moderate correlations. It suggests that the morphology of these dunes is controlled by the lakes. Spatially, the lunette dunes present regular arrangement, and the strike of their alignment are approximately in accordance with the linear dunes. The calculated DP implies that the lunette dunes developed under a low-wind-energy environment, which is a wind regime similar to that required for the formation of the surrounding linear dunes. Even though, the resultant DP demonstrates that the summer wind should be responsible for the growth of the lunette dunes. However, accompanied with the repeated drying of lakes and even its disappearance during the dune development process, it not only contributes to the development of lunette dunes but also promotes their transformation to linear dunes.
3
Ellerton, Daniel, Tammy Rittenour, Graziela Miot da Silva, Allen Gontz, James Shulmeister, Patrick Hesp, Talitha C. Santini e Kevin J. Welsh. "Late-Holocene cliff-top blowout activation and evolution in the Cooloola Sand Mass, south-east Queensland, Australia". Holocene 28, n. 11 (6 agosto 2018): 1697–711. http://dx.doi.org/10.1177/0959683618788679.
Testo completoAbstract (sommario):
Cliff-top dunes are a locally important geomorphic features of sedimentary coasts. They are traditionally interpreted as being sourced by (or with) sand derived from the beach below the cliff. This paper presents the results of a stratigraphic and geochronological study of Carlo Sand Blow, a coastal blowout that has developed on top of a high sandy cliff in the Cooloola Sand Mass, south-east Queensland. We use a combination of sedimentological, pedological and geophysical techniques along with optically stimulated luminescence dating to determine the depositional history and evolution of the blowout. We demonstrate that the blowout is dominantly nourished by sand eroded from its floor rather than the adjacent beach. The original dune surface dates to the first half of the last glacial period (c. 40–70 ka) and this dune was deflated in the late-Holocene. Dune activity is directly associated with cliff undercutting because of coastal retreat in the late-Holocene, but coastal erosion on its own is not capable of maintaining aeolian activity. Blowout activity occurred between 2.6 and 2.3 ka and again at 0.3 ka with aeolian sand burying palaeosols. Both soil surfaces contained charcoal and tree stumps in growth position and our study suggests that fire is the immediate trigger for blowout reactivation. It is likely that these fires were anthropogenic in origin, because the site is somewhat protected from natural fire and the ages coincide with intensification of human use of coastal sites in the area.
4
Urushibara-Yoshino, K. "The soils on the calcareous sand dunes southeast of South Australia". Environmental Geology 28, n. 3 (23 ottobre 1996): 154–60. http://dx.doi.org/10.1007/s002540050088.
Testo completo
5
Ryan, Adrienne L., e Stephen R. Cattle. "Do sand dunes of the lower Lachlan floodplain contain the same dust that produced parna?" Soil Research 44, n. 8 (2006): 769. http://dx.doi.org/10.1071/sr06051.
Testo completoAbstract (sommario):
Æolian dust deposits are known to be widespread in south-eastern Australia, with the dominant model being that of ‘parna’, an aggregated material comprising clay, calcium carbonate, and silt-sized quartz. Despite a general acceptance of the parna model, there is surprisingly little evidence of silt-sized clay aggregates remaining in parna profiles. To investigate a relatively pure æolian dust deposit within the proposed zone of parna distribution, we examined the various phases of 3 source-bordering sand dunes on the lower Lachlan River floodplain of south-western NSW. In each dune exists an upper-slope phase of coarse brown sand, a mid-slope layer of reddish, clay-enriched sand, and a lower-slope phase of coarse sand dominated by an accumulation of carbonate glaebules. Granulometric analyses of the clay-enriched phase(s) of each dune identified a conspicuous particle population in the 20–60 μm range, and another in the fine-silt/clay range (<10 μm). Mineralogical characterisation revealed an abundance of illite and kaolinite in the upper 2 dune phases, coupled with a minor amount of smectite, further suggesting an allochthonous æolian origin, as the surrounding floodplain is smectite-rich and relatively poor in illite. Micromorphological features within the clay-enriched phase, including abundant argillans and laminar bands of well-sorted fine quartz grains, indicate that this clay is a depositional feature, illuviated from surface horizons and re-deposited at depth. A similar illuvial origin is suggested by the fine crystalline nature of the calcium carbonate accumulation, ubiquitously coating the matrix mineral grains of the lower dune phase. No discrete clay aggregates were identified; however, all the assumed components of parna (silt-sized quartz grains, clay, and calcium carbonate) were identified, spatially separated within each dune. The consistency of these features among the 3 dunes indicates an analogous æolian dust accession, but it is not clear whether the clay component of this dust was transported as coatings on quartz grains, or as silt-sized clay aggregates accompanied by silt-sized quartz grains.
6
Val, J., T. Mazzer e D. Shelly. "A new record of the dusky hopping mouse (Notomys fuscus) in New South Wales". Australian Mammalogy 34, n. 2 (2012): 257. http://dx.doi.org/10.1071/am11031.
Testo completoAbstract (sommario):
The dusky hopping mouse, Notomys fuscus, is a desert rodent that occurs in the Simpson Strzelecki Dunefield Bioregion in Queensland, South Australia and New South Wales, where stabilised sand dunes are its preferred habitat. A recent capture from the Broken Hill Complex Bioregion in an atypical habitat (bluebush shrubland) and new locality ~170 km south of the nearest New South Wales record may indicate a significant population eruption and subsequent migration into new areas following the widespread ephemeral and perennial plant production pulse that occurred in 2010.
7
Matthews, E. G. "Origins of Australian arid-zone tenebrionid beetles". Invertebrate Systematics 14, n. 6 (2000): 941. http://dx.doi.org/10.1071/it00021.
Testo completoAbstract (sommario):
Three biogeographic components with very different histories are represented among the tenebrionids of the Australian arid zone: the Indo-Malayan element, which is related mainly to the Indonesian fauna; the Austral Gondwanan element, mainly related to that of southern South America; and one here called Tethyan, related to the fauna of northern hemisphere arid regions. Indo-Malayan groups appear to have arrived comparatively recently, probably by invasion from the north, and are differentiated within the arid zone mainly to the species level. Austral groups are the most diverse and have radiated extensively to generic level from ancestors inhabiting sclerophyll forest, probably by vicariance, within the present arid zone. Tethyan groups are endemic in the arid zone at tribal level and have no forest-inhabiting relatives anywhere. They have often become myrmecophilous in Australia, and because of their distribution patterns in the northern hemisphere, partial occurrence in coastal dunes, and apparently basal phylogenetic positions are surmised to have descended by vicariance from inhabitants of the coastal sand dunes of the Tethys Sea, probably in the Jurassic before there was an arid zone in Australia.
8
Huntley, D. J., J. T. Hutton e J. R. Prescott. "South Australian sand dunes: A TL sediment test sequence: Preliminary results". Nuclear Tracks and Radiation Measurements (1982) 10, n. 4-6 (gennaio 1985): 757–58. http://dx.doi.org/10.1016/0735-245x(85)90086-9.
Testo completo
9
Smith, Cathy. "Tin City: Nomadic occupation, colonization and resistance in the sand dunes of Stockton Bight, Australia". Design Ecologies 9, n. 1 (1 giugno 2020): 93–109. http://dx.doi.org/10.1386/des_00006_1.
Testo completoAbstract (sommario):
This article explores nomadic site occupation as a form of planetary colonization involving both human and non-human agents. Conventional understandings of temporary occupation are often humancentric with little attention paid to the disruption of extant site ecologies and processes. The latter are particularly pressing concerns in nomadic settlements located in precarious landscapes. Taking the latter as its focus, this article engages the earth as an agent resisting its own colonization in the Australian-licensed squatter settlement known colloquially as Tin City. Located within the largest mobile sand dune structure in New South Wales, Tin City is an assemblage of several self-built fishing shacks accommodating a nomadic population. Its occupants engage in a daily battle against the shifting sands that threaten to subsume their temporary homes. Located in an area of significant indigenous heritage, the Tin City settlement has become a tourist attraction shrouded in local lore. Current discourses about it and its architectures generally focus on its unusual aesthetics, its contested sociopolitical histories and its ecology, with some discussion on the impacts of European colonization on the sand dune’s dynamic geomorphology. To concentrate on the latter, the article develops and deploys the posthumanist conceptualization of the earth posited by Iranian philosopher Reza Negarestani in his ficto-critical text Cyclonopedia: Complicity with Anonymous Materials. Negarestani ascribes the earth with sentient and agentic capacity, whilst the nomads who traverse its surfaces become the penultimate planetary colonizers. Tin City’s occupation thus becomes a story of colonization and resistance narrated by the earth itself, and a reminder that the production and consumption of architectural forms does not need to be confined to that which is conventionally human.
10
Maze, KM, e RDB Whalley. "Sex-Ratios and Related Characteristics in Spinifex sericeus (Poaceae)". Australian Journal of Botany 38, n. 2 (1990): 153. http://dx.doi.org/10.1071/bt9900153.
Testo completoAbstract (sommario):
Spinifex sericeus R.Br. is a dioecious, stoloniferous grass which occurs on sand dunes around much of the south-eastern coastline of Australia, New Zealand and New Caledonia. Sex ratios of ramets of S. sericeus and some associated characteristics were studied on the mid-north coast of New South Wales. Generally there was a male bias in the observed ramet sex ratio, although the extent of this bias varied with the beach investigated, the position in the dunes and the time of sampling. Male inflorescences matured and died more rapidly than females, and hence the observed male bias was greatest at the beginning of the flowering period. Male ramets were found to have more sexual tillers per clump than female ramets. The genet sex ratio was estimated from plants grown from seed and separated from each other throughout the experimental period. Males and females were found to be equal in number, although this equality may not be a true reflection of the genet sex ratio in the field.
11
Chen, Xiang Yang. "Quaternary sedimentation, parna, landforms, and soil landscapes of the Wagga Wagga 1 : 100 000 map sheet, south-eastern Australia". Soil Research 35, n. 3 (1997): 643. http://dx.doi.org/10.1071/s96071.
Testo completoAbstract (sommario):
The Wagga Wagga 1 : 100 000 map sheet is on the Western Slopes of southern New South Wales. The regional topography changes from hills in the east and south-east to gently sloping rises and alluvial plains in the west. Aeolian clays (parna) form a consistent clay regolith regardless of the underlying geology in the gently sloping areas. In some alluvial plains and on some lower hill slopes, the surficial sediments contain a significant portion of reworked parna. In hilly areas, parna is poorly preserved except on some remnant ancient land surfaces, such as dissected plateaux and piedmont plains. The soil pattern in the area is well controlled by landform processes and history. On relatively steep hill slopes, locally derived materials from weathering of bedrock are usually the dominant components of the soils, and geology is the dominant factor controlling soil distribution. In contrast, the Murrumbidgee high floodplain is covered by uniform silty clay with deep clayey soils (brown/grey Dermosols). Before the mid-Holocene, the alluvium mainly comprised sands and gravels, which were reworked by wind forming sand sheets and sand mounds (source-bordering dunes) on which deep sandy soils (Rudosols) now occur. The sediments and soils on the alluvial plains of local streams vary according to their distance from the source area and the flooding frequency. Areas considered to be mantled by parna, uniform red clayey soils (haplic red Kandosols/Chromosols) occur. Although the distribution pattern of the soils is controlled by the landform evolution, the relationships between soil morphological properties and topography are not readily quantified. On the alluvial and gently sloping landforms, soil properties usually show little change even though slope gradient and slope length vary. Some soils, e.g. the Rudosols on the sand sheets, rarely show any topographic features which may indicate their presence. In limited areas, e.g. on steeper hills formed on metasedimentary rock, the soil properties vary with changes in topographic parameters (slope gradient and slope length).
12
Page, K. J., A. J. Dare-Edwards, J. W. Owens, P. S. Frazier, J. Kellett e D. M. Price. "TL chronology and stratigraphy of riverine source bordering sand dunes near Wagga Wagga, New South Wales, Australia". Quaternary International 83-85 (settembre 2001): 187–93. http://dx.doi.org/10.1016/s1040-6182(01)00039-8.
Testo completo
13
Kirby, GC. "The Population Biology of a Smut Fungus, Ustilago spinificis Ludw. I. Geographic Distribution and Abundance." Australian Journal of Botany 36, n. 3 (1988): 339. http://dx.doi.org/10.1071/bt9880339.
Testo completoAbstract (sommario):
Ustilago spinificis, a floral smut of Spinifex hirsutus and S. sericeus, was collected across southern Australia from Yanchep, W.A. on the west coast to Seaspray, Vic, on the south-eastern coast and from the North Island of New Zealand. The host plants are most abundant on beaches with extensive sand dunes and the smut is common in regions where the host is abundant. The distribution limits for the smut are set by the replacement of S. hirsutus by a non-host, S. longifolius, north of Perth on the west coast; by the absence or rarity of host plants on rocky coastlines across the Great Australian Bight and in the SE. and SW. corners of Australia; and by the limited occurrence of host plants on the east coast of Australia. Spinifex inflorescences were sampled on 33 beaches and on the 29 beaches where smut was found the mean frequency of smutted inflorescences was 22%. These high infection rates represent a natural epidemic of a plant disease and data on other natural populations of smut fungi are presented to show that these results are not exceptional.
14
Bolton, Julia, e Katherine Moseby. "The activity of Sand Goannas Varanus gouldii and their interaction with reintroduced Greater Stick-nest Rats Leporillus conditor". Pacific Conservation Biology 10, n. 3 (2004): 193. http://dx.doi.org/10.1071/pc040193.
Testo completoAbstract (sommario):
The activity pattern of the Sand Goanna Varanus gouldii in northern South Australia was estimated by radio telemetryduring the summer months. Individuals were located within the Arid Recovery Reserve where introduced European Rabbits Oryctolagus cunniculus, Feral Cats Felis catus and European Foxes Vulpes vulpes were removed. Interaction between the re-introduced Greater Stick-nest Rat Leporillus conditor and the Sand Goanna, a potential significant predator in the absence of cats and foxes, was examined. Mean activity area for Sand Goannas was 5.9 ha (�1.0, n = 9), and their summer activity was concentrated on sand dunes rather than the adjacent inter-dunal swales. Tracks of Sand Goannas were found more often around Greater Stick-nest Rat nests than control sites. However, Sand Goanna predation on re-introduced Greater Stick-nest Rats could not be confirmed and most deaths of radio-collared Greater Stick-nest Rats coincided with a period of exceptionally high maximum temperatures and were probably due to heat and dehydration. Sand Goannas scavenged Greater Stick-nest Rat carcasses, and analysis of scats and stomach material revealed that although invertebrates were the most common prey item, mammal material (hair and bones) was present in 20% of scats.
15
Rix, Michael G., Mark S. Harvey e J. Dale Roberts. "A revision of the textricellin spider genus Raveniella (Araneae:Araneoidea:Micropholcommatidae): exploring patterns of phylogeny and biogeography in an Australian biodiversity hotspot". Invertebrate Systematics 24, n. 3 (2010): 209. http://dx.doi.org/10.1071/is09048.
Testo completoAbstract (sommario):
South-western Western Australia is a biodiversity hotspot, with high levels of local endemism and a rich but largely undescribed terrestrial invertebrate fauna. Very few phylogeographic studies have been undertaken on south-western Australian invertebrate taxa, and almost nothing is known about historical biogeographic or cladogenic processes, particularly on the relatively young, speciose Quaternary sand dune habitats of the Swan Coastal Plain. Phylogeographic and taxonomic patterns were studied in textricellin micropholcommatid spiders belonging to the genus Raveniella Rix & Harvey. The Micropholcommatidae is a family of small spiders with a widespread distribution in southern Western Australia, and most species are spatially restricted to refugial microhabitats. In total, 340 specimens of Raveniella were collected from 36 surveyed localities on the Swan Coastal Plain and 17 non-Swan Coastal Plain reference localities in south-western Western Australia. Fragments from three nuclear rRNA genes (5.8S, 18S and ITS2), and one mitochondrial protein-coding gene (COI) were used to infer the phylogeny of the genus Raveniella, and to examine phylogeographic patterns on the Swan Coastal Plain. Five new species of Raveniella are described from Western Australia (R. arenacea, sp. nov., R. cirrata, sp. nov., R. janineae, sp. nov., R. mucronata, sp. nov. and R. subcirrata, sp. nov.), along with a single new species from south-eastern Australia (R. apopsis, sp. nov.). Four species of Raveniella were found on the Swan Coastal Plain: two with broader distributions in the High Rainfall and Transitional Rainfall Zones (R. peckorum Rix & Harvey, R. cirrata); and two endemic to the Swan Coastal Plain, found only on the western-most Quindalup dunes (R. arenacea, R. subcirrata). Two coastally restricted species (R. subcirrata, R. janineae) were found to be morphologically cryptic but genetically highly distinct, with female specimens morphologically indistinguishable from their respective sister-taxa (R. cirrata and R. peckorum). The greater Perth region is an important biogeographic overlap zone for all four Swan Coastal Plain species, where the ranges of two endemic coastal species join the northern and south-western limits of the ranges of R. peckorum and R. cirrata, respectively. Most species of Raveniella were found to occupy long, highly autapomorphic molecular branches exhibiting little intraspecific variation, and an analysis of ITS2 rRNA secondary structures among different species of Raveniella revealed the presence of an extraordinary hypervariable helix, ranging from 31 to over 400 nucleotides in length.
16
McDowell, Matthew C., Alexander Baynes, Graham C. Medlin e Gavin J. Prideaux. "The impact of European colonization on the late-Holocene non-volant mammals of Yorke Peninsula, South Australia". Holocene 22, n. 12 (24 settembre 2012): 1441–50. http://dx.doi.org/10.1177/0959683612455542.
Testo completoAbstract (sommario):
Over the last 200 years Australia has suffered the greatest rate of mammal species extinction of any continent. This demands extensive biodiversity research, but unfortunately has been hampered by poor documentation of Australia’s native species at the time of European colonization. Late-Holocene fossil mammal assemblages preserved in caves, rockshelters and surface lag deposits from deflated sand dunes can provide a more complete understanding of pre-European ecological conditions than can be developed from our knowledge of present biodiversity. In South Australia, few regions have experienced greater landscape modification and biodiversity loss than Yorke Peninsula. We investigate the composition, richness, evenness and age of two owl accumulations from southeastern and southwestern Yorke Peninsula and contrast them with a surface lag deposit assemblage probably accumulated by humans. We then examine the pre-European biogeography of the fauna recovered. The three assemblages have similar species richness, but differ dramatically in composition and evenness. The biases imposed by differing accumulation agents can explain compositional differences between owl and human assemblages, but not the differences between the respective owl accumulations. We argue that key substrate differences – one area is dominated by sand and the other by calcrete – have favoured distinct vegetation communities that fostered distinctly different mammal assemblages from which raptors accumulated prey. The ecological requirements of the extant mammals appear to be reflected in the fossil assemblages, providing support for the application of uniformitarian principles and confidence in the relevance of late-Holocene fossil assemblages to modern conservation and natural resource management.
17
Hodgkin, Ernest P., e Patrick Hesp. "Estuaries to salt lakes: Holocene transformation of the estuarine ecosystems of south-western Australia". Marine and Freshwater Research 49, n. 3 (1998): 183. http://dx.doi.org/10.1071/mf96109.
Testo completoAbstract (sommario):
When the estuaries of south-western Australia were first flooded by the Holocene marine transgression about 7000 years before present (BP), most were enclosed by limestone barrier dunes. Coastal sand drift built bars and flood-tide deltas in the narrow entrances, but until about 3500 years BP the estuaries remained tidal-dominated systems with a diverse marine–estuarine fauna. Now the bars/deltas so obstruct the small tides that estuary water is fresh in winter and marine to hypersaline in summer; the estuaries are river-flow-dominated systems and the ecosystems are characterised by a restricted euryhaline estuarine biota. Some estuaries are still permanently open, their bars/deltas never close, and some are seasonally open, their bars open with river flow in winter and close in summer. Other estuaries are normally closed, their bars remain closed for several years and break with episodic flood flow, or are permanently closed coastal salt lakes with bars that never or rarely break: they can become grossly hypersaline and may dry up altogether. An hypothesis to explain this Holocene transformation of the estuaries attributes it principally to sedimentary processes in an environment where river flow is highly seasonal, tides are microtidal, there was a fall in sea level, and there are differences in the volume and periodicity of flow and the degree of shelter to the entrances from the prevailing south-west winds and swell.
18
Knight, James T., Catherine J. Nock, Martin S. Elphinstone e Peter R. Baverstock. "Conservation implications of distinct genetic structuring in the endangered freshwater fish Nannoperca oxleyana (Percichthyidae)". Marine and Freshwater Research 60, n. 1 (2009): 34. http://dx.doi.org/10.1071/mf08022.
Testo completoAbstract (sommario):
The maintenance of genetic diversity and gene flow in threatened species is a vital consideration for recovery programs. The endangered Oxleyan pygmy perch Nannoperca oxleyana has a fragmented distribution within coastal freshwater drainages of southern Queensland and northern New South Wales, Australia. In the present study, mitochondrial DNA control region variation was used to assess genetic diversity and structure across the geographical range of this species. Haplotypic diversity was highest in a small NSW subcatchment south of Evans Head (h = 0.594) followed by Marcus Creek in Queensland (h = 0.475). Distinct genetic differentiation was evident among the Queensland localities and the NSW subcatchments, implying restricted gene flow between coastal river systems. One of the nine haplotypes detected was distributed over 83.4% of the species’ range, suggesting historical connectivity among the now fragmented populations. These patterns were concordant with eustatic changes associated with the last glacial maximum. High barrier sand dunes may also act as barriers to gene flow and dispersal between adjacent NSW subcatchments. Conservation efforts should focus on the preservation of genetic diversity by maintaining as many genetically differentiated populations as possible. The relatively diverse populations inhabiting the South Evans Head subcatchment and Marcus Creek require special management consideration.
19
Doyle, Thomas B., Andrew D. Short, Peter Ruggiero e Colin D. Woodroffe. "Interdecadal Foredune Changes along the Southeast Australian Coastline: 1942–2014". Journal of Marine Science and Engineering 7, n. 6 (4 giugno 2019): 177. http://dx.doi.org/10.3390/jmse7060177.
Testo completoAbstract (sommario):
Foredunes are important features within coastal landscapes, yet there are relatively few medium to long-term studies on how they evolve and change over time. This study of Australia’s New South Wales (NSW) foredunes has used 70 years of aerial photographs (or photogrammetry) and recent Light Detection and Ranging (LiDAR) datasets to assess multi-decadal fluctuations in foredune morphology. It was shown that over the past 70 years NSW foredunes have exhibited considerable spatial variation, ranging from accretion/aggradation to recession. Those sites that accreted predominantly extended seaward as new incipient dunes, gaining a maximum of 235 m3 m−1 in sand volume over the study period (for the entire dune system). These sites were commonly found in the north of the state, within closed sediment compartments, and with strong onshore (and alongshore) wind climates present (increasing the potential for aeolian sand transport). Stable foredunes were those that remained within +/− 50 m3 m−1 of their initial volume and managed to recover from the various storm impacts over the study period. The majority of these sites were found within the central to southern half of the state, behind embayed beaches, and within leaky sediment compartments, or those that have estuarine sinks. Finally, those foredunes in recession have retreated landwards and/or have reduced in height or width, and lost up to 437 m3 m−1 of sand volume over the study period. There was no clear spatial trend for these sites; however, generally they were found in compartments that had unusual orientations, had disruptions in longshore drift/cross shore sand delivery (i.e., rocky reefs), or were being impacted by humans (i.e., the installation of river training walls, sand bypassing systems, or coastal management programs). This study has shown that NSW foredunes have undergone substantial recent changes and, by understanding their past history, will provide better insight into how they can be managed into the future.
20
Karubian, Jordan. "The Social Organization and Mating System of the Striated Grasswren". Condor 103, n. 2 (1 maggio 2001): 412–17. http://dx.doi.org/10.1093/condor/103.2.412.
Testo completoAbstract (sommario):
Abstract This paper summarizes the breeding biology, social organization, and mating system of the Striated Grasswren (Amytornis striatus), a member of one of the least-known genera of Australian passerines, the grasswrens. I studied 18 color-banded groups and 14 nests in South Australia for one breeding season in 1996. Mean territory size was 3.0 ha, and territories consisted of sandy dunes dominated by spinifex (Triodea irritans). This apparent dependency on mature spinifex, coupled with poor dispersal ability, suggests that the Striated Grasswren is particularly susceptible to habitat destruction. Most groups consisted of socially monogamous pairs, mean group size was 2.1 adults, and the adult sex ratio was 0.95 (males:females). The average clutch size was 2.2 ± 0.4 eggs and an average of 1.1 ± 1.1 young fledged per nesting effort. A male and a female provided similar amounts of parental care at a single nest. Cloacal protuberance size and amount of sperm collected did not suggest intense sperm competition among males.
21
Moseby, K. E., e J. L. Read. "Population Dynamics and Movement Patterns of Bolam's Mouse, Pseudomys bolami, at Roxby Downs, South Australia." Australian Mammalogy 20, n. 3 (1998): 353. http://dx.doi.org/10.1071/am98353.
Testo completoAbstract (sommario):
Basic ecological data were collected on Bolam's mouse, Pseudomys bolami, during a six year trapping study at Roxby Downs in northern South Australia. Pseudomys bolami inhabited mixed arid land systems in the Roxby Downs area, sheltering in the longitudinal orange sand dunes but foraging at night principally on the adjacent chenopod swales. Distances of up to 334m were traversed in a single night and recapture rates were high within trapping sessions but low between sessions suggesting wide-ranging movements and short-term residency. Dietary observations imply an omnivorous diet. Whilst the closely related P. hermannsburgensis is regarded as having an opportunistic breeding strategy, P. bolami reproduced opportunistically but also regularly in spring and early summer. Different reproductive strategies may be influenced by the latitudinal distribution of P. bolami near the southern margin of the arid-zone, where rainfall can occur at any time of year but winter rainfall is more predictable. This contrasts with P. hermannsburgensis, which inhabits more northerly arid areas where rainfall is erratic and unpredictable. There was a 10 fold fluctuation in P. bolami captures over the trapping period with numbers of P. bolami and house mice, Mus domesticus peaking 12 months after above average rains during 1992. Rodent captures remained high for two years afterwards. Although P. bolami persisted throughout the study period, M. domesticus was only present when conditions were above average. Trap success of P. bolami or M. domesticus did not vary between the five sub habitats at the 1 ha study site. However, trap success of P. bolami was positively related to vegetation cover, particularly cover of low bluebush, Maireana astrotricha. Maireana astrotricha may be important in providing both food and cover for P. bolami, a scenario consistent with the utilisation of spinifex, Triodia spp. by P. hermannsburgensis in the northern arid-zone. Past over- grazing of chenopod shrublands may have reduced cover and contributed to the suggested decline in the distribution of P. bolami.
22
Orchard, A. E. "A revision of Cassinia (Asteraceae: Gnaphalieae) in Australia. 6. Section Cassinia". Australian Systematic Botany 22, n. 5 (2009): 344. http://dx.doi.org/10.1071/sb09018.
Testo completoAbstract (sommario):
The present paper completes a taxonomic revision of Cassinia subg. Cassinia, a group of 35 species separated from subg. Achromolaena by the structure of its inflorescence (capitula arrangement approximately dichasial, giving rise to flat- or round-topped compound inflorescences, as opposed to the irregular or alternate arrangement of capitula in subg. Achromolaena, where the overall shape of the inflorescence is conical or elongate). The seven species of Cassinia sect. Cassinia (C. aculeata, C. thinicola, C. wilsoniae, C. longifolia, C. aureonitens, C. trinerva and C. cinerea) are keyed, described and illustrated, with discussion of ecology, distribution and variation. Cassinia aculeata subsp. nova-anglica Orchard, C. thinicola Orchard, C. wilsoniae Orchard and C. cinerea Orchard are described as new. Cassinia aculeata is a variable and widespread species. Four morphological variants are described and discussed, although not formally named. Previously suggested hybridisation between C. aculeata and Ozothamnus obcordatus is discussed, and dismissed. A new subspecies, narrowly endemic to the New England region of New South Wales (NSW), and separated by 350 km from subsp. aculeata, is described. Cassinia longifolia is similarly widespread and variable, particularly in indumentum and leaf shape. Again, four more or less distinct local morphological variants are described, but they are not formally named because of problems with satisfactory circumscription. Cassinia thinicola is newly segregated from C. aculeata. It is a strikingly distinct species, confined to coastal habitats north and south of Newcastle, distinguished by its (usually) lack of hairs on the upper leaf surface, ochre-coloured inflorescences and compact habit. Cassinia wilsoniae, confined to Wyperfeld National Park in western Victoria, has hitherto been largely overlooked, with specimens assigned to a broadly circumscribed ‘C. uncata’, or C. aculeata or C. longifolia. It is geographically widely separated from all of these taxa. It is unusual in the genus, in being confined largely to the summits of consolidated sand dunes. It has rather small inflorescences with few capitula, and these are ochre-coloured. The leaf margins are strongly revolute, almost completely covering the midrib below, unlike related taxa where the midrib remains uncovered. Cassinia cinerea is a rare species confined to south-eastern Queensland, and hitherto confused with C. laevis and C. collina, both in subg. Achromolaena (and thus with conical inflorescences). It also differs from both in a range of indumentum and leaf characters. The remaining, previously recognised, species are redescribed in detail, and their nomenclature, variation, ecology and distribution are discussed as required.
23
Moseby, K. E., J. Stott e H. Crisp. "Movement patterns of feral predators in an arid environment – implications for control through poison baiting". Wildlife Research 36, n. 5 (2009): 422. http://dx.doi.org/10.1071/wr08098.
Testo completoAbstract (sommario):
Control of introduced predators is critical to both protection and successful reintroduction of threatened prey species. Efficiency of control is improved if it takes into account habitat use, home range and the activity patterns of the predator. These characteristics were studied in feral cats (Felis catus) and red foxes (Vulpes vulpes) in arid South Australia, and results are used to suggest improvements in control methods. In addition, mortality and movement patterns of cats before and after a poison-baiting event were compared. Thirteen cats and four foxes were successfully fitted with GPS data-logger radio-collars and tracked 4-hourly for several months. High intra-specific variation in cat home-range size was recorded, with 95% minimum convex polygon (MCP) home ranges varying from 0.5 km2 to 132 km2. Cat home-range size was not significantly different from that of foxes, nor was there a significant difference related to sex or age. Cats preferred habitat types that support thicker vegetation cover, including creeklines and sand dunes, whereas foxes preferred sand dunes. Cats used temporary focal points (areas used intensively over short time periods and then vacated) for periods of up to 2 weeks and continually moved throughout their home range. Aerial baiting at a density of 10 baits per km2 was ineffective for cats because similar high mortality rates were recorded for cats in both baited and unbaited areas. Mortality was highest in young male cats. Long-range movements of up to 45 km in 2 days were recorded in male feral cats and movement into the baited zone occurred within 2 days of baiting. Movement patterns of radio-collared animals and inferred bait detection distances were used to suggest optimum baiting densities of ~30 baits per km2 for feral cats and 5 per km2 for foxes. Feral cats exhibited much higher intra-specific variation in activity patterns and home-range size than did foxes, rendering them a potentially difficult species to control by a single method. Control of cats and foxes in arid Australia should target habitats with thick vegetation cover and aerial baiting should ideally occur over areas of several thousand square kilometres because of large home ranges and long-range movements increasing the chance of fast reinvasion. The use of temporary focal points suggested that it may take several days or even weeks for a cat to encounter a fixed trap site within their home range, whereas foxes should encounter them more quickly as they move further each day although they have a similar home-range size. Because of high intra-specific variability in activity patterns and home-range size, control of feral cats in inland Australia may be best achieved through a combination of control techniques.
24
Reith, Frank, William Verboom, John Pate e David Chittleborough. "Collaborative involvement of woody plant roots and rhizosphere microorganisms in the formation of pedogenetic clays". Annals of Botany 124, n. 6 (31 maggio 2019): 1007–18. http://dx.doi.org/10.1093/aob/mcz065.
Testo completoAbstract (sommario):
Abstract Background and Aims Previous studies have described the laying down of specific B horizons in south-western Australian ecosystems. This paper presents biomolecular, morphological and physicochemical analyses elucidating the roles of specific woody plant taxa and rhizosphere bacteria in producing these phenomena. Methods Clayey deposits within lateral root systems of eucalypts and appropriate background soil samples were collected aseptically at multiple locations on sand dunes flanking Lake Chillinup. Bacterial communities were profiled using tagged next-generation sequencing (Miseq) of the 16S rRNA gene and assigned to operational taxonomic units. Sedimentation, selective dissolution and X-ray diffraction analyses quantitatively identified clay mineral components. Comparisons were made of pedological features between the above eucalypt systems, giant podzols under proteaceous woodland on sand dunes at the study site of Jandakot and apparently similar systems observed elsewhere in the world. Key Results Bacterial communities in clay pods are highly diverse, resolving into 569 operational taxonomic units dominated by Actinobacteria at 38.0–87.4 % of the total reads. Multivariate statistical analyses of community fingerprints demonstrated substrate specificity. Differently coloured pods on the same host taxon carry distinctive microfloras correlated to diversities and abundances of Actinobacteria, Acidobacteria, Firmicutes and Proteobacteria. A number of these microbes are known to form biominerals, such as phyllosilicates, carbonates and Fe-oxides. A biogenic origin is suggested for the dominant identified mineral precipitates, namely illite and kaolinite. Comparisons of morphogenetic features of B horizons under eucalypts, tree banksias and other vegetation types show remarkably similar developmental trajectories involving pods of precipitation surrounding specialized fine rootlets and their orderly growth to form a continuous B horizon. Conclusions The paper strongly supports the hypothesis that B-horizon development is mediated by highly sophisticated interactions of host plant and rhizosphere organisms in which woody plant taxa govern overall morphogenesis and supply of mineral elements for precipitation, while rhizosphere microorganisms execute biomineralization processes.
25
Hofmann, Harald, Dean Newborn, Ian Cartwright, Dioni I. Cendón e Matthias Raiber. "Groundwater mean residence times of a subtropical barrier sand island". Hydrology and Earth System Sciences 24, n. 3 (19 marzo 2020): 1293–318. http://dx.doi.org/10.5194/hess-24-1293-2020.
Testo completoAbstract (sommario):
Abstract. Fresh groundwater on barrier islands is affected by changing sea levels and precipitation variability due to climate change and is also vulnerable to anthropogenic processes, such as contamination and groundwater over-abstraction. Constraining groundwater mean residence times (MRTs) and flow paths is essential for understanding and managing these resources. This study uses tritium (3H) and carbon-14 (14C) to determine the MRTs of groundwater along a transect across subtropical North Stradbroke Island, south-east Queensland, Australia. Hydraulic properties, major ion geochemistry and stable isotopes are used to validate residence times and to identify the processes responsible for their variability. 3H activities range from less than 0.01 to 1 TU (tritium units), which are values lower than those of local average rainfall (1.6–2.0 TU). 14C concentrations range from 62.5 to 111 pMC (percent modern carbon). Estimated MRTs determined using lumped parameter models and 3H activities range from 37 to more than 50 years. Recharge occurs over the entire island, and groundwater MRTs generally increase vertically and laterally towards the coastal discharge areas, although no systematic pattern is observed. MRTs estimated from 14C concentrations display similar spatial relationships but have a much greater range (from modern to approximately 5000 years). Water diversion and retention by lower-permeability units in the unsaturated parts of the dune systems are the most likely course for relatively long MRTs to date. The results indicate that the internal structures within the dune systems increase MRTs in the groundwater system and potentially divert flow paths. The structures produce perched aquifer systems that are wide-spread and have a significant influence on regional recharge. The geochemical composition of groundwater remains relatively consistent throughout the island, with the only irregularities attributed to old groundwater stored within coastal peat. The outcomes of this study enhance the understanding of groundwater flow, recharge diversion and inhibition for large coastal sand masses in general, especially for older sand masses that have developed structures from pedogenesis and dune movement. With respect to south-east Queensland, it allows the existing regional groundwater flow model to be refined by incorporating independent MRTs to test models' validity. The location of this large fresh groundwater reservoir, in dry and populous south-east Queensland, means that its potential to be used as a water source is always high. Background information on aquifer distribution and groundwater MRTs is crucial to better validate impact assessment for water abstraction.
26
Lipar, Matej, e John Webb. "The Middle–Late Pleistocene Bridgewater Formation on Cape Bridgewater, south-western Victoria: chronostratigraphy and palaeoclimatic significance". Proceedings of the Royal Society of Victoria 127, n. 2 (2015): 81. http://dx.doi.org/10.1071/rs15020.
Testo completoAbstract (sommario):
The Pleistocene Bridgewater Formation is well exposed at Cape Bridgewater and surrounding areas in south-western Victoria, where field studies, mineralogical and isotopic analyses and OSL dating have shown that it can be divided into three members, here named (in stratigraphic order) the Descartes Bay, Bats Ridge and Duquesne members. Each member consists of aeolian calcarenite deposited as a coastal dune, that was karstified (with solution pipe development) and then overlain by a red or purple palaeosol. The aeolianites were deposited in three distinct phases corresponding to interglacials MIS 11, MIS 9 and MIS 7, respectively, when the shoreline was near present sea level. Karstification occurred as a result of the high effective precipitation characteristic of the transition between interglacial and glacial periods, followed by aeolian dust accession and palaeosol formation during the drier, windier glacial climates. Comparison with the coeval Tamala Limestone in south-western Western Australia shows simultaneous changes in palaeoclimate: high effective precipitation during the transition from MIS 11 to MIS 10, and a relatively dry transition from MIS 9 to MIS 8. Abundant rainfall during MIS 5 caused extensive limestone dissolution (solution pipes in Victoria, pinnacles in Western Australia) and the resulting quartz sand residue was redeposited during MIS 2-4.
27
Westcott, V. C., N. J. Enright, B. P. Miller, J. B. Fontaine, J. C. Lade e B. B. Lamont. "Biomass and litter accumulation patterns in species-rich shrublands for fire hazard assessment". International Journal of Wildland Fire 23, n. 6 (2014): 860. http://dx.doi.org/10.1071/wf13006.
Testo completoAbstract (sommario):
Fuel age is an imprecise surrogate for fire hazard in species-rich Mediterranean-type shrublands. We present an efficient method for aerial biomass and litter estimation of shrublands on sandy and calcareous substrates in south-western Australia that enables fuel accumulation patterns to be compared independently of vegetation age. For sites ranging 3–16 years since last fire, total available fuel loads were 2.7–7.6tha–1 for the sandplain and 2.6–8.14tha–1 for the calcareous shrublands. Despite calcareous shrublands having higher soil nutrient concentrations and winter rainfall, total available fuel loads were similar between community types over the range of fuel ages examined. Sandplain biomass was dominated by resprouters and calcareous sites, by non-sprouters. Topographic variation in fuel loads was observed among sandplain sites, with greater available biomass and litter on the deeper sands of dunes compared to swales. More rapid fuel accumulation at the youngest sites and more uniform canopy structure in the calcareous shrublands indicate that they have the potential to support fire at shorter intervals than the sandplain. For each community type, an allometric equation based on the relationship between average maximum plant height and total available fuel was derived that enables rapid estimation of fuel loads that is more accurate than using fuel age.
28
Slender, Amy Lee, Marina Louter, Michael G. Gardner e Sonia Kleindorfer. "Plant community predicts the distribution and occurrence of thick-billed grasswren subspecies (Amytornis modestus) in a region of parapatry". Australian Journal of Zoology 65, n. 4 (2017): 273. http://dx.doi.org/10.1071/zo17081.
Testo completoAbstract (sommario):
Habitat heterogeneity can have considerable effects on gene flow and migration across a region of parapatry. Describing habitat across a region of parapatry is important for the development of eco-evolutionary theory. Two subspecies of thick-billed grasswren (Amytornis modestus) share a region of parapatry between the South Australian salt lakes, Lake Eyre and Lake Torrens. While the two subspecies remain morphologically diverged outside the region of parapatry, it is not known what factors within the region of parapatry may affect migration and gene flow. In this study, we test associations between habitat differences and subspecies distributions and discuss whether ecological barriers could play a role in mitigating gene flow between the subspecies. We compare dominant plant species (1) between the allopatric ranges of the subspecies and within their region of parapatry, and (2) in relation to presence or absence of grasswrens within their region of parapatry. We found that the dominant plant species differed between grasswren subspecies in their allopatric range and in their region of parapatry, and also differed in the region of parapatry at sites with or without grasswrens. Specifically, grasswrens were absent in vegetation that is typical of sand dunes. These findings are discussed in light of evidence for secondary contact and hybridisation between A. m. indulkanna and A. m. raglessi, and susceptibility to introgression.
29
Qiu, S., A. J. McComb, R. W. Bell e J. A. Davis. "Nutrient response to soil and litter metabolic activity in a transect across a seasonal wetland". Marine and Freshwater Research 54, n. 3 (2003): 243. http://dx.doi.org/10.1071/mf02156.
Testo completoAbstract (sommario):
Many wetlands in the interdunal depression of coastal sand dunes of the Swan Coastal Plain are surrounded by partially vegetated catchments. Although litter can be an important source of nutrients, little is known about litter related microbial activity in these catchments, especially its role in regulating nutrient concentrations in soils during the wet season. Heterotrophic microbial activity and phosphorus (P) dynamics were monitored before and after the onset of the wet season along transects from a vegetated catchment to the lakebed in Thomsons Lake, south-western Australia. Microbial activity was measured in the field as CO2 efflux (range from 47 to 176 mg CO2 m–2 h–1) and in the laboratory as substrate-induced-respiration (SIR; range from 11 to 133 μg g–1 h–1). Substrate-induced-respiration was positively correlated with soil organic content, and was concentrated in surface soils. In contrast, in the exposed lakebed most microbial biomass was below the surface, in the 10–30 cm depth zone. There were significant changes in nutrient dynamics in response to soil microbial activity. Before rain, P extracted by anion exchange membrane (PAEM) was well correlated with site litter and plant debris (r2 = 0.90, P�<�0.001), suggesting that PAEM in soils was litter-sourced. This relationship was modified during the wet season: there was an overall increase in microbial biomass P (PMB; from average 7.5 μg g–1 to 21.6 μg g–1), and a decrease in PAEM : PMB in surface soils. Along the study transect, the assimilation index PAEM : PMB declined towards the wetland, where soils were more silty and organic, and CO2 production was significantly higher. Our data suggest that heterotrophic microbial activity has a significant role in regulating P flux from catchment litter during the wet season, which would affect the mobility of litter-sourced P from catchment to the wetland.
30
Watling, R., e M. Rotheroe. "Macrofungi of sand dunes". Proceedings of the Royal Society of Edinburgh. Section B. Biological Sciences 96 (1989): 111–26. http://dx.doi.org/10.1017/s0269727000010885.
Testo completoAbstract (sommario):
SynopsisOur knowledge of the macrofungi of British sand dune systems is outlined and similarities and differences are discussed, based both on intensive studies and scattered observations, particularly in Scotland and Wales. Comparisons are made with European sand dune communities, and much wider observations from as far afield as N.E. Australia and North America are presented. Several records new to Britain are documented.
31
Alappat, Linto, Palaniandy Seralathan, Anil Shukla, Kyth Thrivikramji e Ashok Singhvi. "Chronology of red dune aggradations of South India and its Palaeo-environmental significance". Geochronometria 40, n. 4 (1 dicembre 2013): 274–82. http://dx.doi.org/10.2478/s13386-013-0118-5.
Testo completoAbstract (sommario):
Abstract Red sand dunes occur in the coastal plains of south east and west of Tamil Nadu, India between the coordinates of 8°00′ to 9°30′ N; 77°18′ to 79° 00′ E. OSL dating of these sands indicated aggradations between ∼16-9 ka and ∼9-3 ka in the west and east coasts respectively. Dating results from inland red dunes at the foothills of Western Ghats show a break in deposition at ∼6 ka and aggradation since ∼2 ka. The sand aggradations in the west coast occurred during the transition period when SW monsoon in the area was reestablishing. The dunes attained their stability by 9 ka. In the coastal region, the aggradations were controlled by sea level changes and a local recycling of earlier dunes (in the east coast). In the inland areas, the dune building was controlled by sand supply from fluvial sources.
32
Goldsmith, Victor. "Coastal sand dunes as geomorphological systems". Proceedings of the Royal Society of Edinburgh. Section B. Biological Sciences 96 (1989): 3–15. http://dx.doi.org/10.1017/s0269727000010824.
Testo completoAbstract (sommario):
SynopsisThe importance of aeolian deposition is clearly shown by the size and bulk of coastal dunes. Sand dunes occur where there is a large supply of sand, a wind to move it, and a place in which it can accumulate. A dune classification is presented which takes into account the origin, internal geometry and surface geomorphology of coastal dunes. Since the main element that distinguishes coastal dunes from desert dunes is vegetation, the relative amount of vegetation may be used as a typology. Four dune types are distinguished: vegetated dunes, parabolic dunes, medanos (i.e. large sand hills devoid of vegetation), and artificially-inseminated dunes. Vegetated and medano dunes are the end members, with parabolic dunes in between. Parabolic dunes are “anchored” by vegetation, but the centre of the dunes has migrated in the down-wind direction. The artificially-inseminated dunes are formed by vegetation plantings, fencing, or other artificial means, but with natural sand accumulation around these obstacles. These now account for a very substantial portion of the world's coastal dunes.The role of wind and its relation to the internal geometry (i.e. cross-bed dip and direction) are discussed in some detail, with examples from Brazil, U.S. east and south coasts, Israel and China. Differences in these characteristics are detailed, and related to the different modes of formation of the four dune types.The role of the wind in transporting and depositing sand in coastal areas is being quantified through both wind tunnel and field transport measurements. An example from a field study along the coast of Israel illustrates the differences between desert and coastal dune transport, where the role of vegetation and beach topography must be taken into account. From the Israeli study, and others, it appears that transport in coastal dunes is reduced by one-third to one-half of that in deserts, due to these factors.Coastal dunes provide a useful, and often necessary, buffer against storm waves and the presently rising sea level. They form primarily through vertical sand accretion trapped by the sensitive dune vegetation. Provided that sufficient space exists between the high tide line and developed areas, planned dunes can be easily formed with the aid of plantings and fencing.
33
Swezey, Christopher S., Arthur P. Schultz, Wilma Alemán González, Christopher E. Bernhardt, William R. Doar, Christopher P. Garrity, Shannon A. Mahan e John P. McGeehin. "Quaternary eolian dunes in the Savannah River Valley, Jasper County, South Carolina, USA". Quaternary Research 80, n. 2 (settembre 2013): 250–64. http://dx.doi.org/10.1016/j.yqres.2013.06.007.
Testo completoAbstract (sommario):
Sand hills in the Savannah River valley in Jasper County (South Carolina, USA) are interpreted as the remnants of parabolic eolian dunes composed of sand derived from the Savannah River and stabilized by vegetation under prevailing climate conditions. Optically stimulated luminescence ages reveal that most of the dunes were active ca. 40 to 19 ka ago, coincident with the last glacial maximum (LGM) through early deglaciation. Modern surface winds are not sufficient for sustained eolian sand transport. When the dunes were active, winds blew at velocities of at least 4 m/s from west to east, and some vegetation was present. The ratio of annual precipitation to potential evapotranspiration (P:PE) was less than the modern ratio of 1.23 and may have been < 0.30, caused by stronger winds (which would have resulted in greater evaporation) and/or reduced precipitation. The Savannah River dunes are part of a larger assemblage of eolian dunes that were active in the eastern United States during and immediately after the LGM, suggesting that eolian sediment behavior in this region has been controlled by regional forcing mechanisms during the Quaternary.
34
Chiu, Ching-Sang, Ben Reeder, Linus Chiu, Yiing Jang Yang e Chifang Chen. "South China Sea upper-slope sand dunes acoustics experiment". Journal of the Acoustical Society of America 136, n. 4 (ottobre 2014): 2316. http://dx.doi.org/10.1121/1.4900394.
Testo completo
35
OHMORI, H. "Remobilized dunes of the Millicent coast, South Australia". Journal of Geography (Chigaku Zasshi) 96, n. 1 (1987): Plate1—Plate2. http://dx.doi.org/10.5026/jgeography.96.plate1.
Testo completo
36
Greene, R. S. B., W. D. Nettleton, C. J. Chartres, J. F. Leys e R. B. Cunningham. "Runoff and micromorphological properties of a grazed haplargid, near Cobar, NSW, Australia". Soil Research 36, n. 1 (1998): 87. http://dx.doi.org/10.1071/s97024.
Testo completoAbstract (sommario):
We investigated the effects of 2 different grazing regimes on the surface soil properties of a dunefield land system in the semi-arid woodlands of eastern Australia. Sandy siliceous, thermic Xeric Haplargids (Siliceous Sands, Uc1·23) occur on the sandy, 2–4-m-high longitudinal dunes. Fine-loamy, siliceous, thermic Xeric Haplargids (Massive Red Earths, Uc2·13) occur in the swales between the dunes. We compared very high-intensity grazing (approx. 1 year) by feral goats with low-intensity grazing (approx. 4 years) by sheep. A rainfall simulator, applying water at the rate of 30 mm/h, measured the hydraulic properties of the surface soils formed under the 2 different grazing regimes. We examined undisturbed samples of the upper 5-cm layer of the soil surface using micromorphological techniques. In the swales, there were no differences in the effects of the 2 grazing regimes on soil properties. At low-intensity sheep grazing (0·2–0·3 sheep/ha), the soil surface on the dunes remained in an excellent condition. The surface had a good vegetative cover and consisted of either loosely packed sand grains, or areas where the sand grains were bonded together by clay and organic matter to form an organic crust. The total carbon content of the 0–2 cm depth of soil was 0·86%. Both soil surfaces have a high infiltration rate (i.e. >30 mm/h) and also appear to contain stable microaggregates of parna material distributed among the eolian sand grains. Very high-intensity goat grazing (up to 4·0 goats/ha) rapidly depleted the perennial grasses, killed most of the shrubs, and converted the soil surface on the dunes to one highly susceptible to erosion by wind. The low total carbon content (depth 0–2 cm) of 0·3% and absence of iron-stained clay coatings on the sands further support this view. The surface soil on the dunes in the very high-intensity goat-grazing plots consisted of either loosely packed sand grains or areas where poorly orientated clays coated the sand grains to form a strong, physical crust. We suggest that the physical crust may cause a change in the hydrology of the land system which may enhance the conditions for recruitment of unpalatable shrubs in the dune–swale interface. This increase in unpalatable shrubs and decrease in perennial grasses caused by the very high intensity goat grazing is therefore detrimental to the long-term productivity of these semi-arid lands.
37
Ghate, SD, KR Sridhar e NC Karun. "Macrofungi on the coastal sand dunes of south-western India". Mycosphere 5, n. 1 (febbraio 2014): 144–51. http://dx.doi.org/10.5943/mycosphere/5/1/6.
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Knight, Jasper, e Helene Burningham. "Sand dunes and ventifacts on the coast of South Africa". Aeolian Research 37 (aprile 2019): 44–58. http://dx.doi.org/10.1016/j.aeolia.2019.02.003.
Testo completo
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Muhs, Daniel R., James B. Swinehart, David B. Loope, Josh Been, Shannon A. Mahan e Charles A. Bush. "Geochemical Evidence for an Eolian Sand Dam across the North and South Platte Rivers in Nebraska". Quaternary Research 53, n. 2 (marzo 2000): 214–22. http://dx.doi.org/10.1006/qres.1999.2104.
Testo completoAbstract (sommario):
AbstractGeochemical and geomorphic data from dune fields in southwestern Nebraska provide new evidence that the Nebraska Sand Hills once migrated across the North and South Platte rivers and dammed the largest tributary system to the Missouri River. The Lincoln County and Imperial dune fields, which lie downwind of the South Platte River, have compositions intermediate between the Nebraska Sand Hills (quartz-rich) and northeastern Colorado dunes (K-feldspar-rich). The most likely explanation for the intermediate composition is that the Lincoln County and Imperial dunes are derived in part from the Nebraska Sand Hills and in part from the South Platte River. The only mechanism by which the Nebraska Sand Hills could have migrated this far south is by complete infilling of what were probably perennially dry North Platte and South Platte river valleys. Such a series of events would have required an extended drought, both for activation of eolian sand and decreased discharges in the Platte River system. A nearby major tributary of the North Platte River is postulated to have been blocked by eolian sand about 12,000 14C yr B.P. We propose that an eolian sand dam across the Plattes was constructed at about this same time.
40
Cooper, Ranessa L., e David D. Cass. "A comparative epidermis study of the Athabasca sand dune willows (Salix; Salicaceae) and their putative progenitors". Canadian Journal of Botany 81, n. 7 (1 luglio 2003): 749–54. http://dx.doi.org/10.1139/b03-064.
Testo completoAbstract (sommario):
The Athabasca sand dunes are located on the south shore of Lake Athabasca in northern Alberta and Saskatchewan, Canada. Four willow shrubs (Salix; Salicaceae) occur on the open sands, two of which are endemic to the Athabasca sand dunes. Light and scanning electron microscopy were used to quantify stomatal frequency, stomatal index, trichome density, and cuticle thickness, for the Athabasca sand dune willows and their associated putative progenitors. The Athabasca sand dune taxa (Salix brachycarpa var. psammophila, Salix planifolia subsp. tyrrellii, Salix silicicola, and Salix turnorii) occur primarily on the inner dunes, and each has certain leaf epidermal features that appear to be adaptive to the exposed nature of the open sand habitat and the high light intensity. Salix brachycarpa var. psammophila and S. silicicola have tomentose leaves, with trichome densities that are significantly greater than those of their respective widespread progenitors. Salix planifolia subsp. tyrrellii and S. turnorii have amphistomatic leaves and substantially thicker cuticles than their associated progenitors. This investigation is the first to compare adaptive leaf epidermis features within the derivativeprogenitor Salix pairs. Considerations for the significance of amphistomaty in the Athabasca sand dune Salix taxa are discussed.Key words: Athabasca sand dunes, cuticle, Salix, stomata, trichomes, willow.
41
Chiu, Ching Sang, Linus Y. Chiu, Chi-Fang Chen, Yiing Jang Yang, Ruey Chang Wei, Steven R. Ramp, Chris Miller, D. Benjamin Reeder e Andrea Y. Chang. "Acoustic experiments over the South China Sea upper-slope sand dunes". Journal of the Acoustical Society of America 140, n. 4 (ottobre 2016): 3012. http://dx.doi.org/10.1121/1.4969344.
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Lubke, R. A., A. M. Avis e J. B. Moll. "Post-mining rehabilitation of coastal sand dunes in Zululand South Africa". Landscape and Urban Planning 34, n. 3-4 (maggio 1996): 335–45. http://dx.doi.org/10.1016/0169-2046(95)00227-8.
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Zouaouid, Khadidja, e Rachid Gheriani. "Mineralogical Analysis of Sand Roses and Sand Dunes Samples from Two Regions of South Algeria". Silicon 11, n. 3 (28 settembre 2018): 1537–45. http://dx.doi.org/10.1007/s12633-018-9974-1.
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Walker, Joe, Brian Lees, Jon Olley e Cliff Thompson. "Dating the Cooloola coastal dunes of South-Eastern Queensland, Australia". Marine Geology 398 (aprile 2018): 73–85. http://dx.doi.org/10.1016/j.margeo.2017.12.010.
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Györgyövics, Katalin, Tímea Kiss e György Sipos. "Grain Size Distribution of Stabilised Aeolian Dune Sediments in Inner Somogy, Hungary". Journal of Environmental Geography 7, n. 3-4 (1 novembre 2014): 21–30. http://dx.doi.org/10.2478/jengeo-2014-0009.
Testo completoAbstract (sommario):
Abstract In Inner Somogy the former researches concluded that the grain size of stabilised aeolian dunes decreases from north to south fitting to grain size distribution of the alluvial fan the dunes were built of and to the prevailing wind. However, the trend is not so evident, if considering the dune types and sand moving periods. The aim of this paper is to analyse the grain size distribution trends from the point of view of (1) different dune classes, (2) OSL age and (3) general morphological characteristics of the region. During the analysis the grain size distribution of 345 samples from 17 cores (120-300 cm in depth) was determined, and 15 OSL samples were dated. According to the results, the material of simple forms and level 1 dunes (these are the lowest dunes on the surface of the alluvial fan) becomes finer southward, in accordance with the structure of the alluvial fan and prevailing wind direction. Similar trend applies for level 2 dunes (which were formed on the top of level 1 dunes), but it does not apply for level 3 dunes, which are situated on the top of other dunes. It seems that the grain size is inversely proportional to the size of a dune and its age, thus younger and smaller dunes have coarser and less well sorted material. The sediments of the oldest, large parabolic dunes are the finest, younger, medium size parabolic forms have fine material, and the youngest hummocks contain the coarsest sand. The decreasing grain size towards south is the most apparent along longitudinal residual ridges, while within parabolic dunes the wings contain finer material than their elevated head.
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Clemmensen, Lars B. "Aeolian morpho_logy preserved by lava cover, the Precambrian Mussartut Member, Eriksfjord Formation, South Greenland". Bulletin of the Geological Society of Denmark 37 (14 ottobre 1988): 105–16. http://dx.doi.org/10.37570/bgsd-1988-37-09.
Testo completoAbstract (sommario):
Investigations of sedimentary deposits in elastic interval 5 of the Mussartilt Member have revealed the occurrence of aeolian sandstones. The aeolian deposits rest on pebbly sandstones and conglomerates of fluvial origin, and the are sharply overlain by a c. 70 m thick lava flow. The aeolian sandstones comprise up to 10 m thick and 200 m wide dome-shaped bodies that are initiated by thin and patchily preserved aeolian sand sheet deposits. The bulk of the aeolian sandstone bodies constitute low-medium-angle, dipping lee-side deposits of dome-shaped dunes. The dome-shaped dunes migrated towards a zone of distal alluvial fans perhaps during the influence of prevailing NE trade winds. Superimposed smaller-scale dunes formed during periodic strong winds from the E. Erosion of the dunes at the base of the lava flow was insignificant and most of the original dome-shape form of the dunes seems to have been preserved. The dome-shaped dunes may represent part of a migrating erg system, but continued dune migration was stopped by extrusion of the lava flow.
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SCHAWALLER, WOLFGANG. "A new genus and species of Tentyriini (Coleoptera: Tenebrionidae) from sand dunes in Namaqualand, South Africa". Zootaxa 3514, n. 1 (11 ottobre 2012): 79. http://dx.doi.org/10.11646/zootaxa.3514.1.5.
Testo completoAbstract (sommario):
Archinamaqua gen. n. lyleae sp. n. (Pimeliinae Latreille, 1802, Tentyriini Eschscholtz, 1831) is described from the sand dunes of Namaqualand in northwestern South Africa. It is related to the genera Broomium Koch, 1950 and Archinamibia Koch, 1952. All these taxa are wingless and highly adapted nocturnal sand dwellers in dry habitats of the same area in northwestern South Africa and southern Namibia.
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Łabuz, Tomasz Arkadiusz, Ralf Grunewald, Valentina Bobykina, Boris Chubarenko, Algimantas Česnulevičius, Artūras Bautrėnas, Regina Morkūnaitė e Hannes Tõnisson. "Coastal Dunes of the Baltic Sea Shores: A Review". Quaestiones Geographicae 37, n. 1 (30 marzo 2018): 47–71. http://dx.doi.org/10.2478/quageo-2018-0005.
Testo completoAbstract (sommario):
Abstract The article summarises results of studies conducted along the Baltic Sea sandy coasts by scientists involved in coastal dune research, and presents an attempt to describe the types and distribution of dune coasts. The Baltic Sea coasts feature lower and higher foredunes. The lowland behind the coastal dune belt is covered by wandering or stabilised inland dunes – transgressive forms, mainly parabolic or barchans. The source of sediment for dune development includes fluvioglacial sands from eroded coasts, river-discharged sand, and older eroded dunes. Due to the ongoing erosion and coastal retreat, many dunes have been eroded, and some are withdrawing onto the adjacent land. There are visible differences between the south-eastern, western, and northern parts of the Baltic Sea coast with respect to dune development. The entire southern and eastern coast abounds in sand, so the coastal dunes are large, formerly or currently wandering formations. The only shifting dunes are found at the Polish and the Russian–Lithuanian coasts on the Łebsko Lake Sandbar as well as on the Vistula and Curonian Spits. The very diverse shoreline of the south-western coast experiences a scarcity of larger sandy formations. Substantial parts of the Baltic Sea sandy coasts have been eroded or transformed by humans. The northern part of the Baltic Sea coast features mainly narrow and low sandy coasts (e.g. in Estonia). Further north, sandy dunes are virtually absent.
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Tejan-Kella, MS, DJ Chittleborough, RW Fitzpatrick, CH Thompson, JR Prescott e JT Hutton. "Thermoluminescence dating of coastal sand dunes at Cooloola and North Stradbroke Island, Australia". Soil Research 28, n. 4 (1990): 465. http://dx.doi.org/10.1071/sr9900465.
Testo completoAbstract (sommario):
Thermoluminescence (TL) of quartz grains has been used to date a soil horizon at each of four sites in a chronosequence of freely drained podzols at Cooloola and North Stradbroke Island. The chronological order of the TL dates is in agreement with the sequence of inferred ages based on stratigraphic, geomorphic, denudational and pedological evidence, but at least one of the TL dates is of considerably greater age than the field evidence implies. Possible explanations of this anomaly are discussed. Differences in the nature of the quartz grains and the various pre-treatments used in TL dating were also examined by using a combination of thermogravimetric analysis (TGA), differential thermal analysis (DTA) and scanning electron microscopy (SEM) methods. The DTA showed no dissimilarity among the quartz samples from the different sites, but the TGA results showed significant weight losses for some samples and pretreatments. The SEM method further showed that weight loss is associated with water-sorbing substances (allophanic materials) present as coatings on grain surfaces and/or in cracks within grains.
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Reeder, D. Benjamin, Andrea Y. Chang, Chi-Fang Chen, Ching-Sang Chiu, Linus Y. Chiu, Chris W. Miller, Steven R. Ramp, Ruey C. Wei e Yiing J. Yang. "Acoustic propagation in the South China Sea: Internal waves and sand dunes". Journal of the Acoustical Society of America 140, n. 4 (ottobre 2016): 3013. http://dx.doi.org/10.1121/1.4969347.
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