Plantation forests and biodiversity conservation

There are five key reasons why biodiversity conservation should be considered a part of plantation management. (1) The plantation estate is large, and balancing various land management values with wood and pulp production is important when extensive areas of land are involved. (2) The locations and management of new plantations will affect the biota that currently exist in such landscapes. (3) Maintaining some elements of biodiversity within plantations can have benefits for stand productivity and the maintenance of key ecosystem processes such as pest control. (4) The retention (or loss) of biota in plantations is relevant to the formulation of ecological standards and the certification of plantations in many parts of the world. (5) Plantation forestry has a narrow and intensive management focus on producing a forest crop for a limited array of purposes. It will not meet future societal demands for a range of outputs from plantations (in addition to wood and pulp supply), and will not be congruent with the principles of ecological sustainability. This paper briefly reviews the biodiversity conservation values of Australian plantation s. It shows that almost all work in Australian plantations, whether conifer or eucalypt, highlights the importance of landscape heterogeneity and stand structural complexity for enhancing biodiversity. Management of plantations to promote landscape heterogeneity and stand structural complexity and enhance the conservation of biodiversity will, in many cases, involve tradeoffs that will affect wood and pulp production. The extent to which this occurs will depend on the objectives of plantation management and how far they extend towards the more complex plantation forestry models that incorporate social and environmental values. We argue that the widespread adoption of plantation forestry that leads to homogenous stands of extensive monocultures will risk re-creating the array of negative environmental outcomes that have been associated with agriculture in many parts of Australia

Just below the surface: developing knowledge management systems using the paradigm of the noetic prism

In this paper we examine how the principles embodied in the paradigm of the noetic prism can illuminate the construction of knowledge management systems. We draw on the formalism of the prism to examine three successful tools: frames, spreadsheets and databases, and show how their power and also their shortcomings arise from their domain representation, and how any organisational system based on integration of these tools and conversion between them is inevitably lossy. We suggest how a late-binding, hybrid knowledge based management system (KBMS) could be designed that draws on the lessons learnt from these tools, by maintaining noetica at an atomic level and storing the combinatory processes necessary to create higher level structure as the need arises. We outline the “just-below-the-surface” systems design, and describe its implementation in an enterprise-wide knowledge-based system that has all of the conventional office automation features

The cat's cradle network

In this paper we will argue that the representation of context in knowledge management is appropriately served by the representation of the knowledge networks in an historicised form. Characterising context as essentially extra to any particular knowledge representation, we argue that another dimension to these be modelled, rather than simply elaborating a form in its own terms. We present the formalism of the cat's cradle network, and show how it can be represented by an extension of the Pathfinder associative network that includes this temporal dimension, and allows evolutions of understandings to be traced. Grounding its semantics in communities of practice ensures utility and cohesiveness, which is lost when mere externalities of a representation are communicated in fully fledged forms. The scheme is general and subsumes other formalisms for knowledge representation. The cat's cradle network enables us to model such community-based social constructs as pattern languages, shared memory and patterns of trust and reliance, by placing their establishment in a structure that shows their essential temporality

Farm Animal Welfare and Quality Verification

Existing empirical evidence suggests that farm animal welfare may not be a top-of-mind issue for many consumers in North America. Nevertheless, there is pressure from animal welfare groups on food retailers and processors to implement more stringent requirements for their suppliers. Is the demand for more stringent animal welfare protocols primarily determined by a subset of consumers with very strong preferences or by an underlying change in consumer and societal preferences? Who do consumers trust for credible quality assurances with respect to farm animal welfare attributes? This paper provides a basis for further analysis of these issues. The roles of different stakeholders in delivering farm animal welfare quality assurances to consumers are first discussed. Then a social welfare analysis of the Canadian market for animal friendly pork is presented under different scenarios with respect to the strength of consumer preferences and the existence of voluntary standards versus mandatory standards. The analysis suggests that a situation of voluntary labelling that is reasonably credible is desirable as it maximizes the welfare that accrues to all players on the market. Furthermore, this scenario allows heterogeneous consumers to choose between different combinations of price and quality according to their preferences. The paper concludes with suggestions for further research.farm animal welfare, quality assurance, labelling, certification, heterogeneous consumers., Agribusiness, Agricultural and Food Policy, Consumer/Household Economics, Demand and Price Analysis, Food Consumption/Nutrition/Food Safety, Q13, Q18,

The interstellar D1 line at high resolution

Observations at a resolving power or a velocity resolution are reported of the interstellar D(sub 1) line of Na I in the spectra of gamma Cas, delta Ori, epsilon Ori, pi Sco, delta Cyg, and alpha Cyg. An echelle grating was used in a double-pass configuration with a CCD detector in the coude spectrograph of the 2.7 m reflector at McDonald Observatory. At least 42 kinematically distinct clouds are detected along the light paths to the five more distant stars, in addition to a single cloud seen toward delta Cyg. The absorption lines arising in 13 of the clouds are sufficiently narrow and unblended to reveal clearly resolved hyperfine structure components split by 1.05 km/s. An additional 13 clouds apparently show comparably narrow, but more strongly blended, lines. For each individual cloud, upper limits T(sub max) and (v sub t)(sub max) on the temperature and the turbulent velocity, respectively, are derived by fitting the observed lines with theoretical absorption profiles

Comparison of the sensitivity of Australasian and non-Australasian aquatic organisms to selected metals

University of Technology, Sydney. Dept. of Environmental Sciences.The difference in sensitivity of Australasian species and their non-Australasian counterparts has not been thoroughly examined. Of those studies that have been undertaken, there was no clear pattern evident regarding which group of species was the most sensitive. The current study aimed to determine if there were any significant differences between the sensitivity of organisms from these two regions by collating metal toxicity data and determining if significant differences were evident using Student t-tests and species sensitivity distribution (SSD) methods. Generally, there was more non-Australasian toxicity data available than Australasian data. Therefore, the availability of sufficient toxicity data for Australasian species determined which metals could be investigated. The metals for which there was sufficient data were As(III), As(V), Cd, Cr(VI), Cu, Pb, Hg, U and Zn for freshwater organisms and Cd, Cr(VI), Cu, Pb, Hg, Ni, and Zn for marine/estuarine organisms. Data was assessed using quality assessment criteria that were tested and improved as part of this study. The quality of the toxicity data was assessed in order to ensure that only acceptable quality data were used in the comparisons. Statistical comparisons of the best available freshwater data revealed that 35% of the comparisons had significant differences (p 0.05) detected between the marine/estuarine organisms. SSDs could be derived for Cd, Cu and Zn in both fresh and marine/estuarine waters using acute toxicity data. Australasian freshwater organisms exposed to Cu were found to be significantly (p 0.05). Estimated chronic trigger values (ECTVs) were derived using acute to chronic ratios. When comparing these ECTVs the Australasian organisms were found to be significantly more sensitive (p 0.05). Assessment factors were calculated using the ratio of the sensitivity of Australasian and non-Australasian species to the selected metals and then plotting the cumulative frequencies against the ratio. This analysis revealed that an assessment factor of 7.1 would need to be applied to protect 95% of Australasian organisms in freshwater ecosystems from 95% of chemicals studied, while an assessment factor of 2.2 would be needed to ensure that 95% of Australasian marine/estuarine organisms would be adequately protected from 95% of chemicals studied when using non-Australasian toxicity data to derive trigger values. The observed differences in sensitivity of Australasian and non-Australasian organisms to metals indicate that using non- Australasian data could cause either over or under protection of the local species and that this kind of study should be conducted with other chemical groups

Pulsar timing noise and the minimum observation time to detect gravitational waves with pulsar timing arrays

The sensitivity of pulsar timing arrays to gravitational waves is, at some level, limited by timing noise. Red timing noise - the stochastic wandering of pulse arrival times with a red spectrum - is prevalent in slow-spinning pulsars and has been identified in many millisecond pulsars. Phenomenological models of timing noise, such as from superfluid turbulence, suggest that the timing noise spectrum plateaus below some critical frequency, $f_c$, potentially aiding the hunt for gravitational waves. We examine this effect for individual pulsars by calculating minimum observation times, $T_{\rm min}(f_c)$, over which the gravitational wave signal becomes larger than the timing noise plateau. We do this in two ways: 1) in a model-independent manner, and 2) by using the superfluid turbulence model for timing noise as an example to illustrate how neutron star parameters can be constrained. We show that the superfluid turbulence model can reproduce the data qualitatively from a number of pulsars observed as part of the Parkes Pulsar Timing Array. We further show how a value of $f_c$, derived either through observations or theory, can be related to $T_{\rm min}$. This provides a diagnostic whereby the usefulness of timing array pulsars for gravitational-wave detection can be quantified.Comment: Accepted for publication in MNRA