Lowland Woodland Research Articles

Aboriginal Resource Utilization and Fire Management Practice in Western Arnhem Land, Monsoonal Northern Australia: Notes for Prehistory, Lessons for the Future

This paper considers traditional resources and fire management practices of Aboriginal people living in a near-coastal region of western Arnhem Land, monsoonal northern Australia. The data illustrate that before the arrival of Europeans freshwater floodplains and riverine habitats provided the major proportion of food resources over much of the seasonal cycle. By contrast, the extensive lowland woodlands and open forests, the sparser vegetation of the Arnhem Land escarpment and plateau, and the generally small patches of rain forest (“jungle”), provided relatively few resources, although jungle yams were of critical importance through the relatively lean wet season. The paper then considers burning as a management tool through the seasonal cycle. In broad terms, burning commenced in the early dry season and was applied systematically and purposefully over the landscape. Burning in the late dry season was undertaken with care, and resumed in earnest with the onset of the first storms of the new wet season, particularly on floodplains. These general patterns of resource use and fire management are shown to have applied widely over much of near-coastal northern Australia. The implications of these data for prehistory and for contemporary land management practices in the region, are considered. It is suggested that pre-European patterns of fire management in the region are likely to have been practiced only over the past few thousand years, given the development of abundant food resources in the late Holocene. It is shown that traditional burning practice offers a generally useful, conservative model for living in and managing a highly fire-prone savanna environment.

A study of species richness and diversity in seed banks and its use for the environmental mitigation of a proposed holiday village development in a coniferized woodland in south east England

A survey was carried out to determine the density and species composition of germinable seed in the surface soil layers of 30 plots within a coniferized lowland woodland in East Kent in order to establish the resources available for habitat creation in the event of some areas being modified during a proposed holiday village development. The selected plots included conifer plantations (up to 69 years old), broad-leaved plantations and the semi-natural broad-leaved edges that remain on parts of the perimeter of the site which were used as the control. A total of 13 682 seedlings emerged from the soil samples during the four-month germination trials. Fifty-two species were identified of which eight were ancient woodland indicator species for south-east England. The most abundant species represented in the seed banks were: Juncus effusus, Rubus fruticosus, Carex sylvatica, Betula pendula and Agrostis tenuis. Between-site comparisons of coniferous plots of different ages revealed a marked reduction in the seed species and seed density in plantations over 65 years old. Results of soil nutrient and texture analyses ruled out the likelihood of edaphic factors being responsible for between-site differences in seed bank composition. Seed species richness and diversity (Shannon-Wiener diversity index) were greatest in the semi-natural broad-leaved edges, but the diversity index used also showed that two replanted conifer sites had high values despite few species being present. The usefulness and limitations of diversity indices in the context of seed bank studies is discussed. From the results of the study, management proposals for the site have been put forward in order to maintain floristic diversity and mitigate the impact of the proposed development.

Lowland woodland structure and pattern and the distribution of arboreal, phytophagous arthropods

We investigated factors that limited the distribution of phytophagous species within a woodiand system in Midlothian, Scotland. A pattern analysis was conducted of phytophagous species on a total of 45 Fagus sylvatica within 15 woodlands. Species richness counted on collected leaves was tested against within-and between-wood variables. Variables used in a regression with arthropod data from Fagus were used to estimate the phytophage richness on Betula pendula and Quercus robur in the same woods. Convariance in the number of phytophages in sampled woods was found for Fagus over three years and for Fagus, Betula and Quercus in 1992. Association analysis was used to classify the woods into species rich or poor based on presence or absence matrices. The main factors that limit phytophages on Fagus (gaps along the woodland edge, depth and species richness of the field layer. density of leaf litter and the extent of contiguous woodland cover, when including hedgerows and lines of trees) affect phytophages of similar life history strategy on other tree species within the same woods. Eighty-six per cent of species were lost because certain life history stages were vulnerable to factors that prevail in woods of poor structure. The nature conservation value of woodlands could be assessed using the correlated vulnerability of particular phytophages across tree species under specific woodland conditions.

Seed Bank Composition and Variability in Five Woodlands in South-West England

This paper examines the species composition and variability of the seed banks associated with four lowland woodlands and one upland woodland in south-west England. The sites studied are conifer plantations and neglected and coniferized coppice. The sampling covers a range of stand types, stand ages and management systems, on both acidic and

Broad‐scale patterns in geographical and habitat distribution of migrant and resident passerines in Britain and Ireland

We analysed patterns of breeding habitat use in migrant and resident passerines on a broad geographical scale in Britain. Migrants were less widely distributed than residents and used fewer habitats. Although resident genera that were more widespread used more nesting habitats, this did not hold for migrant genera though it did at the species level. Although migrancy status in Europe has been associated with the use of ‘open’ structural habitat types (e.g. scrubland), evidence from Britain was contradictory. Within lowland woodlands the ratio of migrants to residents and the density of migrants was highest in habitats with large areas of young growth. The highest migrant ratios of all, however, were recorded in mature upland woods, with little or no undergrowth. These upland woods carried the lowest densities of residents. Regression models accounting for variation in the migrant ratios and densities in woodland habitats varied according to the geographical scale on which they were constructed. The extent of young growth was a strong predictor of migrant ratios and densities in south‐east England but not for woods in the north and west. Resident densities in northern and western woods were inversely related to altitude.

Mammalian Diversity and Structure

Mammalia constitute one of the five major classes of vertebrates (the others being Pisces, Amphibia, Reptilia, and Aves). There are, at latest count, some 4,170 species of mammals living today, classified in about 1010 genera, 130–140 families, and 18 orders (Corbet and Hill, 1980; Honacki et al., 1982). In addition, sixteen orders and uncounted genera and species of mammals are known to be extinct (see synoptic classification in Table 1). While most living mammals are terrestrial like their Mesozoic ancestors, one large progressive group has invaded the air (bats, represented by about 150 living genera and 920 species). Two other smaller groups are fully aquatic (whales, including some 40 genera and 80 species; and sirenians, 3 genera and 5 species). Mammals occupy all of the continents, and all of the larger oceanic islands. Faunal diversity is greatest in lowland tropical forests, woodlands, and savannas, decreasing rapidly at high elevations and latitudes.

Physiological aspects of the ecology of Dicranum fuscescens in the subarctic. II. Seasonal patterns of organic nutrient content

Individual plants of Dicranum fuscescens were collected from two field sites (a highland semitundra and a lowland lichen woodland) near Schefferville, Quebec (latitude 55° N), for 4½ months during 1974. Collections were made at 2-week intervals from June until the 2nd week in October. Samples were separated into green and brown shoot components and oven-dried. Subsequently analyses were carried out to determine concentrations of total carbohydrates (sugar and starch) and lipids in the respective tissues. Total carbohydrates were found to increase in the green tissues towards the end of the season reaching a maximum of between 10 and 10.5% ash-free tissue dry weight in October. Lipid concentrations showed a maximum of between 3.6 and 4.0% ash-free dry weight during July and subsequently declined, in the same tissues. Seasonal trends of nutrient concentration in the brown portions of the shoot were not marked.An investigation of biomass distribution in complete plants of D. fuscescens revealed that brown shoots accounted for more than half of the total. Mean lengths of these parts of the shoot were about twice those of the upper stem.

Food of Slugs in Mixed Deciduous Woodland

The palatability of food to 8 species of slug characteristic of lowland woodland on boulder clay soils, is discussed. Faecal analyses show that all 8 species feed largely on plant material but seasonal variations are important and reflect changing food availability. Food palatability experiments suggest that there is a low specificity in the choice of 6 of the slug species but this, together with feeding zone separation, may be sufficient to explain niche separation. The role of slugs as detritivores in woodlands is discussed.

Chromosome variation in British populations of Oncopsis (Hemiptera:Cicadellidae)

The British species of Oncopsis fall into two groups with respect to male karyotype. Four species—O. avallanae, O. carpini and O. subangulata, together with an undescribed new species close to carpini—consistently show ten autosome pairs and a single X-chromosome (2n=10AII+XO). In O. tristis too the XO state predominates but single neo-sex chromosome variants with nine and eight autosome pairs respectively have also been found. The two remaining species-O. alni and O. flavicollis—both regularly include derived neo-XY states involving the incorporation of autosomal material onto the X(2n=9AII+XY). The single population of O. alni studied was entirely neo-XY but the situation in O. flavicollis proved more complex. Montane populations which occur on Betula pubescens are XO-monomorphic whereas populations in lowland woodlands are polymorphic, including both XO and neo-XY types. In such situations the XO forms are found predominantly on B. pubescens whereas the XY morphs predominate on a second species of birch, B. pendula, which is absent from montane woodlands. In all three species where the neo-XY state is present, different autosomes have been involved in the fusion process.