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Abstract: The new species Hypnea corona Huisman & Petrocelli is described to accommodate specimens from Australia, New Zealand, Italy, and Japan that were previously included in the Hypnea comuta complex [...]

Subsoil physicochemical constraints can limit crop production on alkaline soils of south-eastern Australia. Fifteen farmer paddocks sown to a range of crops including canola, lentil, wheat, and barley in the Wimmera and Mallee of Victoria and the mid-north and Eyre Peninsula of South Australia were monitored from 2003 to 2006 to define the relationship between key abiotic/edaphic factors and crop growth. The soils were a combination of Calcarosol and Vertosol profiles, most of which had saline and sodic subsoils. There were significant correlations between [EC.sub.e] and [Cl.sup.-] (r 0.90), ESP and B (r- 0.82), ESP and [EC.sub.e] (r=0.79), and ESP and [Cl.sup.-] (r = 0.73). The seasons monitored had dry precropping conditions and large variations in spring rainfall in the period around flowering. At sowing, the available soil water to a depth of 1.2 m ([θ.sub.a]) averaged 3 mm for paddocks sown to lentils, 28 mm for barley, 44 mm for wheat, and 92 mm for canola. Subsoil constraints affected canola and lentil crops but not wheat or barley. For lentil crops, yield variation was largely explained by growing season rainfall (GSR) and [θ.sub.a] in the shallow subsoil (0.10-0.60 m). Salinity in this soil layer affected lentil crops through reduced water extraction and decreased yields where [EC.sub.e] exceeded 2.2 dS/m. For canola crops, GSR and [θ.sub.a] in the shallow (0.10 0.60m) and deep (0.60-1.20m) layers were important factors explaining yield variation. Sodicity (measured as ESP) in the deep subsoil (0.80-1.00m) reduced canola growth where ESP exceeded 16%, corresponding to a 500 kg/ha yield penalty. For cereal crops, rainfall in the month around anthesis was the most important factor explaining grain yield, due to the large variation in rainfall during October combined with the determinant nature of these crops. For wheat, [θ.sub.a] in the shallow subsoil (0.10-0.60m) at sowing was also an important factor explaining yield variation. Subsoil constraints had no impact on cereal yield in this study, which is attributed to the lack of available soil water at depth, and the crops' tolerance of the physicochemical conditions encountered in the shallow subsoil, where plant-available water was more likely to occur. Continuing dry seasonal conditions may mean that the opportunity to recharge soil water in the deeper subsoil, under continuous cropping systems, is increasingly remote. Constraints in the deep subsoil are therefore likely to have reduced impact on cereals under these conditions, and it is the management of water supply, from GSR and accrued soil water, in the shallow subsoil that will be increasingly critical in determining crop yields in the future. Additional keywords: salinity, sodicity, boron, wheat, barley, lentil, canola., Introduction Rain-fed grain crops grown on highly alkaline soils in southeastern Australia are potentially limited by factors such as water supply and nutrition (Incerti and O'Leary 1990). Low and unreliable [...]

The construction of the Ma:Mu Canopy Walk in the Wooroonooran National Park was completed in August 2008 in culmination of eight years of planning and negotiation with the private sector, the Ma:Mu Traditional Owners and protected area managers. This article examines the attempts to attract a private sector partner to contribute capital to the venture, the process of involving Traditional Owners in protecting cultural heritage places, and dealing with native title rights and interests. The Ma:Mu Canopy Walk diversifies the types of visitor experience opportunities in the Wet Tropics World Heritage Area. The project is the largest single capital works project undertaken by the Queensland Parks and Wildlife in its history. Keywords: rainforest canopy walk, tourism in protected areas, public/private partnerships, Indigenous management, strategic engagement

Our 11 year multidisciplinary study of Koalas (Phascolarctos cinereus) in St Bees Island National Park provides an understanding of the implications of the strategic use of fire and control of introduced browsers, goat and swamp wallaby (Wallabia bicolor) for the maintenance of Koalas, Koala habitat and eucalypt woodlands within the national park. The research involved a close association with the Queensland Parks and Wildlife Service and their staff. This relationship integrated research, park planning and management. The project is a model for research-management integration, especially in relation to information relevance, relationships and understandable, timely communication of research findings. We propose strategies for more general application of this model. Keywords: research-management integration, Koala, Phascolarctos cinereus, protected area management, fire management

Anthropogenic warming of the global climate system is beyond doubt. Impacts from a changing climate are already occurring and the latest scientific research suggests that some aspects are locked in for centuries to come. Climate change therefore poses one of the greatest challenges to Australia's environment and water resources. Historical experience and past trends may no longer be a reliable predictor of the future. This article provides a brief overview of the latest scientific research and thinking on the climate change challenge. Observed changes and projections for temperature, rainfall, extreme events and ocean acidification are presented in an Australian context. The impacts of a range of climate change drivers are summarised, expanding upon the well-accepted general warming and drying trend for southern and eastern Australia. Current thinking regarding 'dangerous' climate change is that we are tracking on the higher end scale or above of the worst case scenario predictions reported by the IPCC Fourth Assessment Report (IPCC AR4) released in 2007. The implications for Australia's water resources, and in particular the Murray-Darling Basin, are significant. There appears to be a brief window of opportunity to act and adapt to enhance resilience to climate change; however, this requires an urgent and sustained commitment, and investment in Australia's environmental assets. Keywords: Climate change, environment, water resources, biodiversity, adaptation, Murray-Darling Basin

An almost complete but predominantly disarticulated ptyctodont fish, Kimbryanodus williamburyensis n. gen., n.sp. from the Late Devonian Gneudna Formation, is described. The fossils occur as three-dimensionally preserved isolated plates, and this has allowed the reconstruction of the fish. A taxonomic revision of the ptyctodonts was undertaken based on recently described Australian taxa and new reconstructions of Australian, American and European specimens. The phylogenetic analysis supports a threefold division of the ptyctodonts, with Rhamphodopsis being the most basal taxon and the other ptyctodonts divided into those possessing a median dorsal spine, spinal plate and simple V-shaped overlap of the anterior lateral and anterior dorsolateral plates and those taxa which do not. Keywords: ptyctodont, phylogeny, Gneudna Formation, Devonian, Australia.

Abstract: Studies of spatial ecology of demersal sharks are critical to understanding the significance of habitat variation; however, limited information exists. Spatial ecology of adult Heterodontus portusjacksoni was studied at [...]

Two key questions regarding the management of Australia's riverine environments are addressed: how much water should be allocated for environmental flows; and how should water entitlements for environmental flows be acquired and managed. First, an application of the choice modelling technique in the context of River Red Gum forests along the River Murray is used to demonstrate how the marginal values of water for the environment can be estimated for comparison against prices paid by extractive users of water. Second, mechanisms in the public and private sectors for the purchase of environmental water are contrasted. Key words: Environmental flows; Non market valuation; Choice modelling, Water trusts JEL Codes: D61, H44, L31, Q51

To determine the effect of wheel traffic and two different management practices on soil compaction and its consequences on physical and chemical soil properties, we measured penetration resistance, water infiltration, bulk density, macroporosity, chemical mobility, air permeability, and soil strength in a conventional orchard (integrated fruit-production program) with bare (sprayed with herbicides) rows and an organic apple orchard with grassed rows. Resistance measurements were taken both within the tree row and the wheel track, down to a depth of 0.35 to 0.40 m. The results indicate that compaction is greater in the wheel tracks under both management methods. Compaction in the wheel track was higher under organic than conventional management. Organic management resulted in a higher macroporosity in both the row and the wheel-track than conventional management. The 'close-to-saturation' infiltration rate was significantly greater within the row of the organic orchard (0.06 m/h) compared with the row of the conventional orchard (0.02 m/h), and compared with the wheel tracks (0.01 m/h). The precompression stress value in the top 100 mm, a measure of the soil strength, was low on all sites. The chemical mobilities were 57 and 50% in the organic orchard, and 86 and 93% in the conventional orchard, respectively, for wheel track and row. Apart from the compaction in the wheel track of the organic orchard, physical and chemical soil characteristics were in a better condition compared with the conventional orchard. Additional keywords: penetrometer, infiltration, chemical mobility, precompression stress, wheel track., Introduction Intensive trafficking in orchards by heavy machinery can cause soil compaction. This can change the soil structure and pore system (Peng et al. 2004), both pore size distribution and [...]

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.jenvman.2005.08.002 Byline: Monika Muschal Abstract: An ecological risk assessment was performed on salinity levels of the Hunter River and its tributaries to respond to concerns that high salinity may be damaging aquatic ecosystems. Probabilistic techniques were used to assess likelihood and consequence, and hence the risk to aquatic biota from salinity. Continuous electrical conductivity distributions were used to describe the likelihood that high salinity would occur (exposure dataset) and toxicity values were compiled from the limited literature sources available to describe the consequence of high salinity (effects dataset). The assessment was preliminary in the sense that it modelled risk on the basis of existing data and did not undertake site-specific toxicity testing. Some sections of the Hunter River catchment have geologies that are saline because of their marine origins. Catchment development has increased the liberation rates of salts into surface-waters. Such modifying activities include coal-mining, power generation and land clearing. The aquatic biota of tributaries had a greater risk of impairment from high salinity than that of the Hunter River. High salinities in the tributaries were attributed to the combined factors of naturally saline geologies, increased liberation of salts due to modification of the landscape, and reduced dilution by flushing flows. A salinity guideline trigger value of 1100mgL.sup.-1 was recommended. Author Affiliation: N.S.W. Department of Infrastructure, Planning and Natural Resources, P.O. Box 2185, Dangar N.S.W. 2309, Australia Article History: Received 10 May 2004; Revised 2 August 2005; Accepted 3 August 2005

Abstract--Morphological development of the larvae and small juveniles of estuary perch (Macquaria colonorum) (17 specimens, 4.8-13.5 mm body length) and Australian bass (M. novemaculeata) (38 specimens, 3.3-14.1 mm) (Family Percichthyidae) [...]

The conceptualization of alien invasive species conflates two axes of variability that have become unhelpfully blurred. The nativeness/alienness axis refers to the presumed belonging of a species in ecological or social space. Invasiveness refers to the behavior of the species in question, particularly in relation to other species. The overlay of nation introduces further variability. Teasing these axes apart is important for more effective environmental management. We examine these concepts using two influential forms of ecological knowledge: the biogeographical and ecological literature and the vernacular experiences of suburban backyarders. Three case studies, the invasive native Pittosporum undulatum and two invasive exotics, Lantana camara and Cinnamomum camphora, illustrate the complex and contingent nature of human interactions with such species and the potential for human interactions to increase and/or reduce the propagation of plant species. Keywords: Australia, backyards, Cinnamomum camphora, Lantana camara, Pittosporum undulatum, weeds., Species have been moving around the globe throughout the ecological history of the Earth. These movements have accelerated in the last few hundred years as a consequence of European colonialism, [...]

An Ecological Footprint is defined as the area of land needed to produce the natural resources a population consumes and to assimilate the waste that population produces. By providing a link between consumption and lifestyle and available ecological space, the Ecological Footprint illustrates the concepts of carrying capacity and sustainability. This article presents the results of a detailed study of Australia. The results indicate the Ecological Footprint of the average Australian is approximately 6 hectares per capita. This is more than 4 times the globally available 'fair share', placing Australia among the top five consuming nations in the world. This result highlights the unsustainable global nature of the Australian lifestyle, particularly the level of consumption of energy and animal products, with large inequities between Western countries such as Australia, and developing countries.

This paper reports the outcomes of a study to review the effectiveness of integrated resource management (IRM) in Australia with specific reference to watershed management. Based on the outcomes of implementation activity and policy reviews, guiding principles were used to develop a set of options for improving watershed management in Australia. These included priority planning and investment framework processes; improving the linkages between regional economic development and integrated resource management; cofinancing watershed management partnerships; and developing a contractual basis for commonwealth cofinanced investments in regional integrated resource management programs. The paper also discusses the use of a best management practice (BMP) approach to watershed management, the use of appropriate multidimensional indicators to measure performance gains in watershed management, and application of the study results as well as the BMP approach to locations beyond Australia.