Palynological differentiation between genera of the Moraceae family and implications for Amazonian palaeoecology

The Moraceae family is one of the most abundant and ecologically important families in Neotropical rainforests and is very well-represented in Amazonian fossil pollen records. However, difficulty in differentiating palynologically between the genera within this family, or between the Moraceae and Urticaceae families, has limited the amount of palaeoecological information that can be extracted from these records. The aim of this paper is to analyse the morphological properties of pollen from Amazonian species of Moraceae in order to determine whether the pollen taxonomy of this family can be improved. Descriptive and morphometric methods are used to identify and differentiate key pollen types of the Moraceae (mulberry) and Urticaceae (nettle) families which are represented in Amazonian rainforest communities of Noel Kempff Mercado National Park (NKMNP), Northeast Bolivia. We demonstrate that Helicostylis, Brosimum, Pseudolmedia, Sorocea and Pourouma pollen can be identified in tropical pollen assemblages and present digital images of, and a taxonomic key to, the Moraceae pollen types of NKMNP. Indicator species, Maquira coriacea (riparian evergreen forest) and Brosimum gaudichaudii (open woodland and upland savanna communities), also exhibit unique pollen morphologies. The ability to recognise these ecologically important taxa in pollen records provides the potential for much more detailed and reliable Neotropical palaeovegetation reconstructions than have hitherto been possible. In particular, this improved taxonomic resolution holds promise for resolving long-standing controversies over the interpretation of key Amazonian Quaternary pollen records.

Beyond urban legends : an emerging framework of urban ecology, as illustrated by the Baltimore Ecosystem Study

The emerging discipline of urban ecology is shifting focus from ecological processes embedded within cities to integrative studies of large urban areas as biophysical-social complexes. Yet this discipline lacks a theory. Results from the Baltimore Ecosystem Study, part of the Long Term Ecological Research Network, expose new assumptions and test existing assumptions about urban ecosystems. The findings suggest a broader range of structural and functional relationships than is often assumed for urban ecological systems. We address the relationships between social status and awareness of environmental problems, and between race and environmental hazard. We present patterns of species diversity, riparian function, and stream nitrate loading. In addition, we probe the suitability of land-use models, the diversity of soils, and the potential for urban carbon sequestration. Finally, we illustrate lags between social patterns and vegetation, the biogeochemistry of lawns, ecosystem nutrient retention, and social-biophysical feedbacks. These results suggest a framework for a theory of urban ecosystems.

The effect of model configuration on modelled hillslope–riparian interactions

The transfer of hillslope water to and through the riparian zone forms a research area of importance in hydrological investigations. Numerical modelling schemes offer a way to visualise and quantify first-order controls on catchment runoff response and mixing. We use a two-dimensional Finite Element model to assess the link between model setup decisions (e.g. zero-flux boundary definitions, soil algorithm choice) and the consequential hydrological process behaviour. A detailed understanding of the consequences of model configuration is required in order to produce reliable estimates of state variables. We demonstrate that model configuration decisions can determine effectively the presence or absence of particular hillslope flow processes and, the magnitude and direction of flux at the hillslope–riparian interface. If these consequences are not fully explored for any given scheme and application, the resulting process inference may well be misleading.

Assessing the value of imperfect biocontainment nationally: rapeseed in the United Kingdom as an exemplar

Paternal biocontainment methods (PBMs) act by preventing pollen-mediated transgene flow. They are compromised by transgene escape via the crop-maternal line. We therefore assess the efficacy of PBMs for transgenic rapeseed (Brassica napus) biocontainment across the United Kingdom by estimating crop-maternal hybridization with its two progenitor species. We used remote sensing, field surveys, agricultural statistics, and meta-analysis to determine the extent of sympatry between the crop and populations of riparian and weedy B. rapa and B. oleracea. We then estimated the incidence of crop-maternal hybridization across all settings to predict the efficacy of PBMs. Evidence of crop chloroplast capture by the progenitors was expanded to a national scale, revealing that crop-maternal gene flow occurs at widely variable rates and is dependent on both the recipient and setting. We use these data to explore the value that this kind of biocontainment can bring to genetic modification (GM) risk management in terms of reducing the impact that hybrids have on the environment rather than preventing or reducing hybrid abundance per se.

Habitat Split as a Cause of Local Population Declines of Amphibians with Aquatic Larvae

Most amphibian species have biphasic life histories and undergo an ontogenetic shift from aquatic to terrestrial habitats. In deforested landscapes, streams and forest fragments are frequently disjunct, jeopardizing the life cycle of forest-associated amphibians with aquatic larvae. We tested the impact of habitat split-defined as human-induced disconnection between habitats used by different life-history stages of a species-on four forest-associated amphibian species in a severely fragmented landscape of the Brazilian Atlantic Forest. We surveyed amphibians in forest fragments with and without streams (referred to as wet and dry fragments, respectively), including the adjacent grass-field matrix. Our comparison of capture rates in dry fragments and nearby streams in the matrix allowed us to evaluate the number of individuals that engaged in high-risk migrations through nonforested habitats. Adult amphibians moved from dry fragments to matrix streams at the beginning of the rainy season, reproduced, and returned at the end of the breeding period. Juveniles of the year moved to dry fragments along with adults. These risky reproductive migrations through nonforested habitats that expose individuals to dehydration, predation, and other hazards may cause population declines in dry fragments. Indeed, capture rates were significantly lower in dry fragments compared with wet fragments. Declining amphibians would strongly benefit from investments in the conservation and restoration of riparian vegetation and corridors linking breeding and nonbreeding areas.

Can agroforest woodlots work as stepping stones for birds in the Atlantic forest region?

In fragmented landscapes, agroforest woodlots can potentially act as stepping stones facilitating movement between forest fragments. We assessed the influence of agroforest woodlots on bird distribution and diversity in the Atlantic forest region (SE Brazil), and also tested which categories of species can use different types of connection elements, and whether this use is influenced by the distance to large forest patches. We studied two fragmented landscapes, with and without stepping stones linking large fragments, and one forested landscape. Using a point count, a bird survey was undertaken in the fragmented landscapes in five different elements: large remnants (> 400 ha), agroforest woodlots (0.4-1.1 ha), small patches (0.5-7 ha), riparian corridor, and pasture areas (the main matrix). Generalist and open-area species were commonly observed in the agroforest system or other connection elements, whereas only a few forest species were present in these connections. For the latter species, the distance of woodlots to large patches was essential to determine their richness and abundance. Based on our results and data from literature, we suggest that there is an optimal relationship between the permeability of the matrix and the efficiency of stepping stones, which occurs at intermediate degrees of matrix resistance, and is species-dependent. Because the presence of agroforest system favors a higher richness of generalist species, they appeared to be more advantageous for conservation than the monoculture system; for this reason, they should be considered as a management alternative, particularly when the matrix permeability requirement is met.

Multivariate modelling of landuse on in-stream salinity over multiple spatial scales

An impediment to sustainable dryland salinity management is the lack of information on contributing factors. GIS and satellite imagery now offer a cost-effective means of generating relevant land and water resource information for integrated regional management of salinity. In this paper the relationships between patterns in land uselcover distribution and base flow salt concentration in streams (indicated by EC) are investigated and modelled. The Glenelg-Hopkins area is a large regional watershed in southwest Victoria, Australia, covering approximately 2.6 million ha. It is currently estimated that 27,400 ha of land is affected by dryland salinity and this is predicted to rapidly increase in the next decade' if current conditions prevail. Salt concentration data from five gauging stations were analysed with multi-temporal land use maps obtained from satellite imagery. Multiple regression analyses demonstrated that the variables Native Vegetation and Dry/and Grain Cropping were the most significant influences on in~stream salinity in the whole catchment (1=88.9%) and 500 m V=88.3%) and 100 m riparian buffers (1=86.9%) during times of base flow. The implications for future land use planning, effectiveness of riparian zones and revegetation programmes is discussed. This work also demonstrates the utility of applying nmltivariate statistical analyses, spatial statistics, and remote sensing with data integrated in a GIS framework for the purpose of predicting and managing the regional salinity threat.

The effects of land use on leaf-litter processing by macro-invertebrates in an Australian temperate coastal stream

Replacement of riparian vegetation by pasture has occurred worldwide and is predicted to have strong effects on macroinvertebrate community structure and function in streams, but this has rarely been examined. In this study, leaf processing and macroinvertebrate community structure were examined in a single stream using experimental leaf-packs and surveys of natural leaf-packs. Two sites in each of three land use categories were selected to represent reaches in forest, pasture and forest-pasture boundary regions. In two experiments using tethered leaf-packs, no differences were found in mean leaf breakdown between land use types. However, shredding invertebrates were absent from the pasture sites, so leaf breakdown in pasture resulted from chemical, physical and microbial processes only. Amounts of fine particulate organic matter in experimental leaf-packs were higher in pasture reaches than the forest and boundary reaches but did not influence leaf breakdown. Macroinvertebrate species richness did not differ between land uses. A predictive model developed for species richness and total abundance enabled direct comparison of assemblages on experimental packs to natural leaf-packs. In the forest reach and at the forest-pasture boundary, macroinvertebrate species richness and total abundance increased proportionally with the number of leaves within a pack, but this relationship was not observed in the pasture reach. Pasture land use on Skenes Creek was therefore associated with weakened relationships between allochthonous inputs and macroinvertebrate communities, but this did not alter leaf breakdown.

Habitat use and distribution of the beautiful firetail (stagonopleura bella) in foothill forests of the Victorian highlands, Australia

The Beautiful Firetail (Stagonopleura bella) is an uncommon, granivorous finch from coastal south-eastern Australia, with a distribution extending from mid-coastal New South Wales to south-eastern South Australia, including Tasmania. This paper presents a quantitative assessment of habitat use by the Beautiful Firetail based on data collected from 30 paired riparian and non-riparian sites in the foothill forests of the Victorian Highlands, Australia. The Beautiful Firetail occurred in two of the three forest blocks surveyed and was found almost exclusively at riparian sites. The Beautiful Firetail was most likely to occur at riparian sites on the coastal fall of the ranges at sites with high sedge cover and low cover of shrubs and bare ground. The species occurred at low densities (0.10–0.19 individuals ha^–1) throughout the year. Records from the Atlas of Victorian Wildlife were used to describe the distribution of Beautiful Firetails in Victoria. Notable observations inland of the Great Dividing Range were recorded during the present study. Further study is required to understand the ecological requirements of the Beautiful Firetail throughout its range.

Analysis of forest policy using multi-attribute value theory

Contents:
1. Role of multi-criteria decision making in natural resource management /​ Gamini Herath and Tony Prato
2. Analysis of forest policy using multi-attribute value theory /​ Jayanath Ananda and Gamini Herath
3. Comparing Riparian revegetation policy options using the analytic hierarchy process /​ M. E. Qureshi and S. R. Harrison
4. Managing environmental and health risks from a lead and zinc smelter : an application of deliberative multi-criteria evaluation /​ Wendy Proctor, Chris McQuade and Anne Dekker
5. Multiple attribute evaluation of management alternatives for the Missouri River System /​ Tony Prato
6. Multi-criteria decision analysis for integrated watershed management /​ Zeyuan Qiu
7. Fuzzy multiple attribute evaluation of agricultural systems /​ Leonie A. Marks and Elizabeth G. Dunn
8. Multi-criteria decision support for energy supply assessment /​ Bram Noble
9. Seaport development in Vietnam : evaluation using the analytic hierarchy process /​ Tran Phuong Dong and David M. Chapman
10. Valuing wetland aquatic resources using the analytic hierarchy process /​ Premachandra Wattage and Simon Mardle
11. Multiple attribute evaluation for national park management /​ Tony Prato
12. The future of MCDA in natural resource management : some generalizations /​ Gamini Herath and Tony Prato.

Paleoenvironmental analysis of a late-holocene subfossil Coleopteran fauna from Starks, Maine

The Sandy River in central Maine Is flanked along much of its length by low terraces. Approximately 100 kg of sediment from one terrace in Starks, Somerset County, Maine was wet-sieved in the field. Over 1100 subfossil Coleoptera were recovered representing 53 individual species of a total of 99 taxa. Wood associated with the fauna is 2000 +/-80 14C Yr in age (1-16,038). The fauna is dominated by species characteristic of habitats apparent in modern central Maine. The subfossil assemblage is indicative of a wide vartety of environments including open ground (e.g., Harpalus pensylvanicus), dense forest (e.g., pterostichus honestus), aquatic environments (e.g., Gyrinus, Helophorus), riparian environments with sand and gravel substrates (e.g., Bembidion inaequale, Schizogenius lineolatus), and moist, organic-rich terrestrial environments (e.g., Micropeplus sculptus). The ecological requirements for each taxon permit an environmental reconstruction suggesting an area vegetationally, climatically, and ecologically similar to that of the Sandy River today. The lowest terraces apparently represent the modern-day floodplain of the Sandy River. An average sedimentation rate of l.00 to 1.04 mm per year has been inferred based on radiocarbon dates here and elsewhere on the Sandy River. The Coleopteran fauna suggests that sand and gravel were distinctly abundant, and that the aggradation of point bars, as seen today, contributed to the flood history. Lateral bank erosion of the modern Sandy River accelerated after the State of Maine mandated cessation of bar removal in 1975: flood severity has dramatically increased since that time. Implications suggest that mining of the bars may be necessary to minimize future flooding problems.

Determinants of native avian richness in suburban remnant vegetation : implications for conservation planning

While urban areas are increasingly recognized as having potential value for biodiversity conservation, the relationship between biodiversity and the structure and configuration of the urban landscape is poorly understood. In this study we surveyed birds in 39 remnant patches of native vegetation of various sizes (range 1–107 ha) embedded in the suburban matrix in Melbourne, Australia. The total richness of species within remnants was strongly associated with the size of remnants. Remnant-reliant species displayed a much stronger response to remnant area than matrix-tolerant species indicating the importance of large remnants in maintaining representative bird assemblages. Large remnants are important for other ecological groups of species including migratory species, ground foraging birds and canopy foraging birds. Other landscape (e.g. amount of riparian vegetation) and structural components (e.g. shrub cover) of remnants have a lesser role in determining the richness of individual remnants. This research provides conservation managers and planners with a hierarchical process to reserve design and management in order to conserve the highest richness of native species within urban areas. First of all, conservation efforts should preferentially focus on the retention of larger remnants of native vegetation. Second, where possible, riparian vegetation should be included within reserves or, where it is already present, should be carefully managed to ensure its integrity. Third, efforts should be focused at maintaining appropriate habitat and vegetation structure and complexity.

Surviving urbanisation : maintaining bird species diversity in urban Melbourne

The relationships between vegetation and bird communities within an urban landscape are synthetised, based on a series of studies we conducted. Our studies indicate that streetscape vegetation plays an important role in
influencing urban bird communities, with streetscapes dominated by native plants supporting communities with high native species richness and abundance, while exotic and newly-developed streetscapes support more introduced bird species and fewer native bird species. Native streetscapes can also provide important resources for certain groups of birds, such as nectarivores. Our research has also revealed that urban remnants are likely to support more native bird species if they are larger and if they contain components of riparian vegetation. Vegetation structure and quality does not appear to be as important a driver as remnant size in determining the richness of native bird communities. Introduced birds were shown to occur in remnants at low densities, irrespective of remnant size, when compared to densities found in streetscapes dominated by exotic vegetation. We discuss our results in terms of practical planning and management options to increase and maintain urban avian diversity and conclude by offering suggestions for future fields of research in terms of urban bird communities.

Impact of stresses imposed on macroinvertebrate communities in two suburban streams

The aim of the project was to determine factors which explain the distribution of macroinvertebrates in two Melbourne streams both drastically affected by urbanisation. A detailed description is given of Dandenong Creek, flowing through the south-eastern suburbs, and Darebin Creek, in the northern suburbs, emphasising stream features likely, or known, to influence the drift and benthic fauna. Faunal sampling was carried out in Dandenong Creek from June 1992 until July 1993, and in Darebin Creek from February 1995 until March 1998. Physicochemical parameters were also recorded. The collected data, together with previously existing data, were analysed using multivariate analyses: non-metric multi-dimensional scaling (NMDS); analysis of similarities (ANOSIM); matching biotic and abiotic variables using BIOENV, and principal component analysis (PCA). Various biotic and diversity indices were calculated in an attempt to identify the major factors responsible for the failure of the fauna to recover from previously more seriously degraded water quality. The contribution of drift to the colonisation potential in Dandenong Creek appeared to be impacted by retarding basins, underground barrel-draining and channelization. Results also indicated that increased conductivity adversely affected the fauna in the lower reaches of Dandenong Creek. It was concluded that in Darebin Creek, high nutrient levels, as well as other pollutants, had resulted in low macroinvertebrate diversity in both the drift and benthos. If, as this study suggests, faunal diversity is a valid measure of stream health, the following factors need to be addressed for catchment-wide, stream management: lack of riparian zone vegetation (increasing bank erosion and making the benthic habitat unstable, with greater temperature variability); control of stormwater runoff (flow variability, increased conductivity, nutrient levels, sediment loads, sewage effluent, industrial discharges and heavy metals), and to modify retarding basins to increase stream continuity.

Riverine macroinvertebrate assemblages up to 8 years

Willow removal followed by riparian revegetation is a widespread river restoration practice in Australia, but the ecological response to this has rarely been evaluated. We sampled river macroinvertebrates from six sites each of three riparian vegetation types: revegetated (treatment), willow-dominated (control) and native forest (reference) in the Gellibrand River catchment during austral spring 2007 and autumn 2008, and measured temperature and light intensity. Revegetated sites varied in age from 1 to 8 years since restoration. Abundances of invertebrates were similar across vegetation types, but were higher during autumn. Macroinvertebrate assemblages at revegetated sites (regardless of age) and at willow-dominated sites showed little among-site variation compared with native forest sites,which showed high site-to-site variability. Water temperatures and light intensity were higher at revegetated sites where works had recently been completed and cooler in native forest sites and long-established revegetated sites. The reduced variability in macroinvertebrate communities among revegetated sites may result from their history as willow-dominated sites or from the disturbance created by willow removal. Either way, these results suggest that longer than 8 years is required before macroinvertebrate assemblages in restored stretches of stream show the variation that appears characteristic of natural sites.