The Pre-Settlement Vegatation of the Western and Central Wimmera Plains of Victoria,Australia

Historical records indicate that the fertile soils of the western and central Wimmera Plains of Victoria, Australia formerly supported grassy woodlands on rises and flats, and grasslands on shallow depressions and clay plains. Soil type and micro-relief appear to have been the major factors that determined the distribution of these communities. Burning of the woodlands by Aborigines may have contributed to their open grassy nature. The few ungrazed remnants of Buloke (Allocasuarina luehmannii) woodland support a suite of species that are absent from or uncommon in other Buloke woodland remnants in the region. This work demonstrates that in districts where little intact native vegetation remains, investigation of the distribution and floristic composition of the pre-settlement vegetation can provide useful information for the maintenance and restoration of remnant vegetation.     

Land of Grass: the Loss of Australia's Grasslands

To a large extent, the Australia of 1788 was characterised not by forests but by open woodlands and grasslands. Yet many of these areas now contain dense forest. Possible explanations for this dramatic vegetational shift include the cessation of Aboriginal burning regimes and the displacement by domestic stock of mammals that ate tree seedlings. While Australia's grasslands were being overrun, elsewhere destructive and wasteful felling of timber continued apace. The problems resulting from such clearance began to be widely articulated in the last two decades of the nineteenth century, but general attitudes to ringbarking and felling have changed only slowly. The result of all this is that Australia's vegetation is now thoroughly disorganised. The grassy woodlands have gone and with them birds, animals and numerous varieties of grass. Any attempt to provide an environment suitable for the majority of native plants and animals in temperate Australia must depend on the restoration of a pre-European-type mosaic of interconnected grassy woodlands.     

Pollen analytical investigations at Crosby Warren, Lincolnshire, in the Vicinity of the iron age and Romano-British settlement of Dragonby

Open-cast ironstone mining at Crosby Warren, near Scunthorpe, Lincolnshire exposed an extensive section through “cover sand” deposits. revealing buried podzol soils and peat layers. Stratigraphic studies, pollen analysis and radiocarbon dating have been carried out on three representative profiles. From these investigations it would appear that the “cover sands” in this area were stabilized under mixed oak woodland by c. 300 BC. After c. 100 BC woodland clearance and farming activities have been distinguished. Local alterations in land-use may be linked with cultural developments at the nearby Iron Age and Romano-British settlement of Dragonby. It is suggested that the impact of man upon the vegetation during Iron Age and Romano-British times probably facilitated podzolization and sand blowing.     

HILLSLOPE TERRACETTES

Several systems of lines of steps or terracettes, commonly known as “cattle tracks” or “sheep tracks”, were observed on treeless, grass-covered hillslopes in the Kislovodsk area of the North Caucasus. Three types are distinguished: (1) anthropogenic, or man-made, tracks, which suggest purposeful human activity and are distinguished by flat-bottomed or concave walkways; (2) animal tracks, connecting grazing areas and distinguished by deeper and narrower walkways produced by hooves; (3) delapsive terracettes (from the Latin delapsus = slip down), produced by a creeplike downslope movement of unconsolidated slope material on top of the bedrock surface. In contrast to the man-made and animal tracks, which have walkways bare of vegetation and grassy side walls, the naturally produced pseudotracks are distinguished by grassy top surfaces and bare side walls. Downslope rates of movement of these natural terracettes are estimated at several tens of millimeters to several centimeters a year.     

Combining pollen and charcoal: evaluating Holocene vegetation composition and dynamics

Pollen analysis reveals vegetation change on a local and regional level over (ideally) continuous time spans but with complications when it comes to the reconstruction of spatially precise species occurrence and composition. Wood charcoal analysis provides site-related information on species occurrence and woodland composition, especially when sediments containing pollen are lacking, but is normally discontinuously available and has the danger of human bias due to potential selection of certain species for e.g. fire making, house construction or charcoal making. Combining the two methods – assuming that suitable palaeoarchives are neighbouring – might compensate for their disadvantages and strengthen the interpretations on vegetation composition and dynamics on a local, extra-local and regional scale. Three examples are given where pollen analysis from “classical” archives – mires and lake sediments – was carried out, and where additionally species identification of wood charcoals was done on samples extracted from close-by archives. The first example (Kugelstattmoos, Bavarian Forest, Germany) combines a Holocene pollen diagram derived from a small mire with late medieval/early modern times charcoal spectra from charcoal production sites which are situated on the margin of the mire. Results show the local occurrence of the main woodland species Fagus sylvatica and Abies alba, and raises new questions on the montane species composition of the formerly natural forests in the Bavarian Forest. The second example (Bargstedter Moor, Schleswig-Holstein, Germany) combines Holocene pollen diagrams from a peat bog with late medieval/early modern times charcoal spectra from charcoal production sites in a woodland close to the bog. It shows the role of Quercus, Fagus, Alnus and Carpinus in medieval and early modern times woodlands and its use by man. The third example (Kleiner Tornowsee, Brandenburg, Germany) combines pollen data from sediments of a small lake with charcoal data derived from Holocene colluvisols and soils. The examples show that anthracological and palynological data complement one another to create a more detailed picture of woodland history and landscape change than one method alone would provide.     

Quantifying woodland resource usage and selection from Neolithic to post Mediaeval times in the Irish Midlands

The antiquity and context (site or feature type) are the two principal factors that act as a framework for interpreting charcoal and wood data from archaeological sites in the recreation of past woodland environments. This research addresses these parameters through the analysis of over 18,000 charcoal fragments from 57 archaeological excavations carried out along a 61?km road scheme in the midland region of Ireland. Observations on spatial vegetation dynamics and woodland resource patterns are also reported on. The data were analysed through percentage frequency and multivariate analyses. The results reveal woodland resource usage in terms of wood types selected for use as fuel or as structural wood as well as patterns of change and variability in taxonomic composition in relation to site types, feature types and time periods. Selection was found to be low in prehistoric times and in particular at burnt mound sites/fulachta fiadh but became increasingly important as time progressed. This has important implications when charcoal from archaeological settings is used in environmental reconstructions.     

Mineral weathering in forest soils and its relevance to the preservation of the buried archaeological resource

There is more woodland in Britain now than for many centuries and considering many international climate change mitigation policies, woodland cover, both in Britain and internationally, is being promoted. However, neither the management of existing woodlands nor their expansion should be at the expense of important archaeological evidence. Due to the large number of known archaeological sites, the large areas of land with uninvestigated archaeological potential and the expanding woodland cover, suitable mitigation strategies need to be developed to allow preservation in situ of important sites. An understanding of how woodland soils and the buried archaeological resource interact is, therefore, essential. This paper utilises ongoing environmental research into the mineral weathering rates in forest soils and considers its application to artefact preservation. The study concludes that soil water pH, its movement, and the saturation of dissolved ions in the soil solution are major factors determining both mineral and artefact longevity. A simple guide to artefact longevity based on these properties is proposed and a geochemical model for predicting loss is tested. These tools could be applied to any soil or individual horizon irrespective of land-use.     

Molluscan Total Assemblages across a Woodland–Grassland Boundary and their Palaeoenvironmental Relevance

Abstract

Molluscan total assemblages across a woodland-grassland boundary are described and analysed using a variety of numerical techniques. These demonstrate that although the Mollusca respond to the vegetation boundaries their response does not exactly parallel that of vegetation structure. In particular, some shade-preferential species have encroached from woodland into adjacent grassland, degree of encroachment being an individual species characteristic. The study indicates that the detection of boundaries in sub-fossil assemblages from buried soil surfaces will only be possible if spatially-oriented multi-sampling strategies are employed.     

The Geography of Natural-Infection Foci of Tick-Borne Encephalitis in the Territory of the USSR

A map of the habitat of tick-borne encephalitis is compared with maps of distribution of various physical-geographic elements to determine significant factors in the formation of natural-infection foci of tick-borne encephalitis. Key factors are found to be a stable climate with annual sums of temperatures close to 2000° C., a dissected terrain, high-grade forest stands with a rich grassy ground vegetation, which supports the domesticated or wild mammals that serve as hosts of adult ticks, and landscapes in which the original forest cover is being re-established after overgrazing or overcutting. Provinces of distribution of infection foci are distinguished in terms of these factors.     

Assessment of Relationships Between Precipitation and Satellite Derived Vegetation Condition Within South Australia

The normalised difference vegetation index (NDVI) has evolved as a primary tool for monitoring continental‐scale vegetation changes and interpreting the impact of short to long‐term climatic events on the biosphere. The objective of this research was to assess the nature of relationships between precipitation and vegetation condition, as measured by the satellite‐derived NDVI within South Australia. The correlation, timing and magnitude of the NDVI response to precipitation were examined for different vegetation formations within the State (forest, scrubland, shrubland, woodland and grassland). Results from this study indicate that there are strong relationships between precipitation and NDVI both spatially and temporally within South Australia. Differences in the timing of the NDVI response to precipitation were evident among the five vegetation formations. The most significant relationship between rainfall and NDVI was within the forest formation. Negative correlations between NDVI and precipitation events indicated that vegetation green‐up is a result of seasonal patterns in precipitation. Spatial patterns in the average NDVI over the study period closely resembled the boundaries of the five classified vegetation formations within South Australia. Spatial variability within the NDVI data set over the study period differed greatly between and within the vegetation formations examined depending on the location within the state. ACRONYMS AVHRR Advanced Very High Resolution Radiometer ENVSAEnvironments of South Australia EOS Terra‐Earth Observing System EVIEnhanced Vegetation Index MODIS Moderate Resolution Imaging Spectro‐radiometer MVC Maximum Value Composite NDVINormalised Difference Vegetation Index NIRNear Infra‐Red NOAANational Oceanic and Atmospheric Administration SPOT Systeme Pour l’Observation de la Terre     

Fire and man in post-glacial woodlands of Eastern England

It has for long been suggested that English early post-glacial woodlands, particularly those dominated by hazel, were a fire-climax vegetation type. This conflicts with the evidence of fire frequency in present-day woodlands. Charcoal and pollen analyses of post-glacial lake sequences in East Anglia, England, suggest that early post-glacial woodlands were not fire-climax types. The pre-5000 BP charcoal record can be best interpreted as a record of intensity of occupation beside lake shores. After 5000 BP, charcoal deposition may reflect increasing use of fire as an agent in land clearance.     

Soils and vegetation history of abandoned enclosures in the New Forest,Hampshire, England

Soil profiles buried beneath earth banks of five abandoned enclosures, ranging in age from late Bronze Age to early 19th century AD, were compared with unburied profiles inside and outside the enclosures. Soil particle size analyses and micromorphological studies show that the banks were constructed of mixed topsoil and subsoil from adjacent ditches; on some banks the soil has begun to podzolize. At the two oldest sites (Dark Hat and Long Slade Bottom, which are late Bronze or Iron Age) the soils within the enclosures were homogenized, probably by occasional cultivation for cereal growing. At Dark Hat an ironpan has developed on the upper surface of a layer compacted by smearing during cultivation. The later enclosures, at Burley Moor (Anglo-Saxon), East Boldre (mediaeval) and Hatchet Gate (early 19th century AD), were probably used entirely for pasture. Pollen assemblages from the buried soils and overlying banks, and chemical comparisons of the buried soils with profiles inside and outside the enclosures together provide new evidence for a history of soil and vegetation changes over the past 2500–3500 years. Heathland vegetation associated with podzolic soils existed on plateau gravels before the late Bronze Age, but on other parent materials heath vegetation and acidic soils with incipient podzolization appeared only in later periods. The present patchy vegetation pattern of mainly deciduous woodland with open areas of ferny grassland and heath seems to have persisted since before the late Bronze Age. The most obvious human influences on the vegetation during the last 2000 years have been periodic temporary use of open areas and woodland clearings for protected grazing.     

The micromammalian fauna from Border Cave,Kwazulu, South Africa

The micromammalian fauna from Border Cave is analysed in terms of community composition and structure. Changes in these aspects are interpreted as indicative of changes in vegetation and climate in the vicinity of the cave during the period of deposition. It would appear that vegetation comprised relatively extensive forest or thick bush and dense grass during wetter phases and fairly open savanna woodland, even open grassland, during drier periods. Variation through time in mean mandibular size in two species of Crocidura (musk shrew) was different both in the two species and from what was expected. It now seems likely that the size change constitutes a response to complex phenomena and not simply to changes in temperature. Comparison with the Boomplaas A sequence indicates that the same general pattern of change is reflected at both sites but that there was a greater amplitude of change at Boomplaas A and that ¹⁸O stage 4 was dry at this site but wet at Border Cave. Evidence for periodic changes in the distribution of various species, and in some cases the mutually exclusive occurrence of ecologically equivalent species, has implications for the zoogeography of the species involved. In particular, the occurrence of Pelomys fallax (creek rat) in the lower half of the sequence is of interest in view of its present distribution 600 + km north of Border Cave.     

Leaf preservation in Eucalyptus woodland as a model for sclerophyll fossil floras

Retallack, G.J., May 2018. Leaf preservation in Eucalyptus woodland as a model for sclerophyll fossil floras. Alcheringa xxx, xxx–xxx.

A comparison of 29 identifiable vascular plant species in litter beneath Eucalyptus woodland with at least 74 species living nearby showed that the litter is a poor representation of standing vegetation. The leaf litter is dominated by sclerophyll leaves, which are a factor of 6.2 over-represented in litter for Angophora costata, factor of 5.7 for Melaleuca linariifolia, of 3.6 for Eucalyptus spp., of 3.5 for Pteridium esculentum and of 2.1 for Acacia linifolia. Angophora leaves are favored by lignification, with denser venation than Eucalyptus leaves. Sparse emergent oil glands of Angophora also provide fewer entry points for bacteria than rotted internal oil glands of Eucalyptus. The myrtaceous taxa Angophora, Eucalyptus, Melaleuca and Kunzea all have oils dominantly of preservative terpene. Melaleuca linariifolia and Acacia linifolia also have leaves and phyllodes (respectively) that are narrow with a thick lignin midrib. Thickly cuticled, succulent, hirsute, pubescent, and pinnate leaves, and green stems are not favored for preservation, because they rot from the inside out. Conspicuously absent in the leaf litter are nonsclerophyll leaves, most grasses and low herbs. This modern sclerophyll leaf litter matches Sydney Basin Permian and Triassic fossil plant localities above nutrient-poor siliceous paleosols, which may have had much more diversity than the preserved fossil flora. Clayey calcareous paleosol leaf litters and lake deposits may record a truer record of local floristic diversity in deep time than sclerophyll leaf litters.

Gregory J. Retallack [gregr@uoregon.edu], Department of Earth Sciences, University of Oregon, Eugene, OR 97403-1272, USA.     

The Airfall-pollen Budget of Archaeologically Important Caves: Creswell Crags, England

This paper investigates fundamental taphonomic issues for palynologists working on archaeologically important cave deposits—the extent to which the pollen and spores reaching the accumulating sediment surfaces reflect the vegetation in cave entrances, or reflect the more regional environments beyond the caves. The study sites were four adjacent caves at Creswell Crags, near Sheffield, England—Church Hole, Dog Hole, C7 and Robin Hood's Cave. The compositions of the pollen and spore assemblages caught in the caves over a one year period were shown to reflect the vegetation in the cave mouths and the wider area beyond. The AP:NAP ratio in the assemblages trapped in the caves corresponded with the proportions of woodland and open ground within a 5 km radius of the site. Comparatively high representations of fern spores in caves were a persistent feature and were attributed to the interactions of habitat, distribution and taphonomic processes—(i) the abundance of ferns in cave mouths, and (ii) the effects produced by a combination of diurnal micro-climatological process interacting with diurnal variations in spore production in the cave entrance. In two caves—Church Hole Cave and Dog Hole Cave—the numbers of grains caught appeared to decline with increasing distance into the cave. In Cave C7, the numbers of grains caught increased towards the back of the cave. The number of grains caught appears to be a principal determinant of the number of plant taxa identified. There were no clear relationships between the presence of a "flue" effect in the cave and the presence of an increase or a decrease in the number of grains caught with changing distance into the caves. It is concluded that as long as account is taken of the particular topographic, microclimatic and taphonomic conditions in these caves, it is possible to infer the character of the vegetation beyond their confines, from the airfall pollen and spores trapped with them at the cave sediment surface.     

Pleistocene frogs from the Darling Downs,southeastern Queensland,and their palaeoenvironmental significance

Systematic collecting from fluvial late Pleistocene deposits from the Darling Downs, southeast Queensland, Australia, has led to the recovery of the first fossil frogs from the region, ail from the Myobatrachidae, a family of ground dwelling and burrowing frogs. The most common species recovered, Limnodynastes tasmaniensis, is extant on the Darling Downs. The fossil taxa include species whose extant populations inhabit arid zones(Limnodynastes sp. cf. L. spenceri), montane forests (Kyarranus spp.), and open woodlands (Neobatrachus sudelli), and indicate the existence of a mosaic of habitats during the Pleistocene. The absence of the Hylidae (tree frogs), a family common throughout the Darling Downs today, may be explained by a taphonomic bias that favours non-arboreal forms. Alternatively, hylids may have been rare or absent on the Darling Downs during the Pleistocene.     

Two middle Cambrian trilobite genera,Cyclolorenzella Kobayashi, 1960 and Jiulongshania gen. nov., from Korea and China

As is widely recognised, fossil florules are difficult to correlate because they appear to have been more controlled by environmental and ecological factors than uniform changes which reflect the passage of geological time. Here I present a worked example of a generally applicable approach to this problem in dating and mapping fossil plant associations.

Floral associations are best described and named by the classical methods of phytosociology. The three dimensional shape of an association in rocks and its palaeoecology can then be critically assessed. For example, during Middle Triassic time the following plant associations would have been encountered on a traverse from the coast to several hundred kilometres inland from the Pacific margin of Gondwanaland: Pachydermophylletum (mangrove scrub), Linguifolietum (coastal swamp woodland), Dicroidietum odontopteroidium (floodplain forest), Phoenicopsetum (levee bank scrub), Dicroidietum odontopteroidium xylopterosum (xerophytic woodland) and Johnstonietum (mallee-like woodland).

The fourth dimension of fossil plant associations (time) is best assessed from the evolution of a prominent group of plants. In conjunction with the ranges of other plant megafossils, evolutionary changes can be used to define Oppel-zones. For the Late Permian to Early Jurassic of eastern Australasia, I have used the evolution of Dicroidium and leaves of related pteridosperm plants together with other species of restricted stratigraphic range or prominent in the definition of the fossil plant associations. From this evidence four Oppel-zones can be recognised. ‘Thinnfeldia’ callipteroides Oppel-zone (Chhidruan to Smithian, 250–230 × 10⁶ years), Dicroidium zuberi Oppel-zone (Smithian to Middle Anisian, 230–220 × 10⁶ years), D. odontopteroides Oppel-zone (Late Anisian to Ladinian, 220–210 × 10⁶ years) and Yabeiella Oppel-zone (Carnian to Rhaetian, 210–200 × 10⁶ years.

In a complete revision of the pteridosperm form-genera Dicroidium, Johnstonia and Xylopteris, a large number of new combinations and the following new taxa are proposed; Dicroidium gouldii sp. nov., D. odontopteroides var. argenteum var. nov., D. odontopteroides var. moltenense var. nov., D. radiatum sp. nov., D. townrovii sp. nov. and Johnstonia coriacea var. obesa var. nov.     

Correlating archaeological and palaeoenvironmental records using a Bayesian approach: a case study from Sutton Common,South Yorkshire,England

This paper presents a case study aimed at correlating archaeological ‘events’ (obtained from radiocarbon measurements and dendrochronology) from the site of Sutton Common with a radiocarbon-dated pollen sequence obtained from a palaeochannel deposit adjacent to the area of the main archaeological activity. It demonstrates the use of a Bayesian approach to quantifying whether the timing of palynological ‘events’ interpreted as reflecting anthropogenic impacts are likely to be associated with archaeological ‘events’. The results suggest that Bronze Age activity in the form of a mortuary enclosure and associated cremation burials are probably not contemporary with the palynological evidence for disturbance to the oak–hazel woodland in this period. Subsequent evidence for local woodland clearance and agriculture is estimated to precede the construction of the large Iron Age enclosure in 372 BC, with increases in ‘anthropogenic indicators’ following this ‘event’. The construction of the site does not appear to have had a pronounced impact on the local vegetation, with hazel the only woody taxon to show clear reductions. Despite the use of a substantial number of oak timbers in the enclosure palisade, percentages of oak remain remarkably stable. Later farming activity on the site probably post-dates the end of activity in the enclosures. The value of the methodology is discussed in relation to quantifiable and robust correlations of archaeological and palaeoenvironmental narratives of landscape and human activity.     

Application of Landsat satellite imagery to monitor land‐cover changes at the Athabasca Oil Sands,Alberta, Canada

A major advantage of satellite remote sensing is that the imagery acquired provides a synoptic view of the landscape. Thus, repeat coverage by the satellite on a regular basis permits the detection of changes in land‐cover over time. This study demonstrates the application of remote sensing technology to the monitoring of mining activities at the Athabasca Oil Sands region of Alberta, Canada. First, we describe the techniques used to match a time sequence of Landsat imagery, both spatially and spectrally, to ensure that the spectral changes through time are due to land‐cover variations. A series of spectral trajectories were then extracted to assess changes in land‐cover through time. Secondly, a land‐cover classification was produced from the baseline 1984 imagery and, using historic and future mine extents, the classification was analyzed to determine the proportion of each land‐cover type affected through development. Results of the analysis indicate that since 1984 there has been a larger reduction in mixedwood dense and broadleaf vegetation classes than mixedwood sparse or dense conifer stands in the area. Based on the delineations of mine‐site activity, the area of woodland and wetland habitat subject to development has increased from approximately 2,520 hectare (ha) in 1984 to 32,930 ha in 2005.     

A GIS Atlas of the Fossil Pollen and Modern Records of Ficus and Related Species for Island South–East Asia,Australasia and the Western Pacific

Ficus has been described as a keystone genus in the tropics. This paper reviews the Quaternary palynology literature, and vegetation research literature in Island Southeast Asia, Australasia and the Western Pacific with the aim of increasing the knowledge of the distribution history for Ficus and related species within this area. Specifically, this paper describes a GIS atlas designed to aid further analysis of the history and spread of Moraceae species. This research project synthesises the knowledge of the distribution and history of Ficus and related species in the greater Australasian area through the production of a GIS atlas, and describes the project, specifically focusing on the data collation and production of the GIS.