Organic agriculture: opportunities and challenges

The organic movement may have gained a place in the spotlight of the mainstream media now, but it has not been like that for long. Since the 1950s, organic farmers operating at a grass roots level have devised, tested and shared production methods. They have codified a set of ideals into a pioneering best practice agricultural management system that addresses multiple community values. Niche markets have gradually been created, commonly based on trust and goodwill (formal certification did not begin until the 1960s and 1970s), and often using novel direct marketing strategies such as box schemes and community supported agriculture. After many years of consumers having to hunt around for their organic produce from several suppliers, perhaps directly from the farmer, the task is now a lot easier with specialist food shops and organic shelf space in supermarkets, in the industrialised world at least. Global links have been forged in all continents as organic agriculture has been seen to be an effective rural development option

Investigation of management practices and economic viability of vineyards for organic wine production

This paper reports the findings of two components of a research investigating the viability of organic wine grape production. Firstly the results of a survey of Australian organic wine grape growers’ management practices and secondly the first year findings of an experimental organic vineyard compared to an associated conventional vineyard. The survey found a heavy reliance on sulphur and copper sprays for powdery and downy mildew control. The experimental vineyard showed similar yields to conventional growing and in many cases higher sugar, though some increase in botrytis in organic Shiraz

Australian Organic Market Report 2010

This is the second report the Biological Farmers of Australia has commissioned to help industry bench mark the growth and health of its sectors. This report - another significant milestone in the two decade plus history of the rapidly developing Australian certified organic sector - builds the information base for industry to benchmark production and market value against past and current claims and estimates and will enable monitoring of future growth of the certified organic market in Australia and its farming and production base. In an industry characterised by operational diversity, this report allows for performance assessment by sector. The next publication in this series is planned in 2012 (biennial since the inaugural report in 2008) as a means of providing the wider industry with invaluable and realistic market information

Australian Organic Market Report 2008

Being four years since the publication of a similar research document, the Australian Organic Market Report (AOMR) 2008 is a landmark report for the organic industry. The report will be invaluable for monitoring and planning the industry development during a period of high growth. Delivering consistent data for benchmarking growth across the various sectors of the industry, it will be a key tool for decision making by organic producers and marketers, along with interested parties such as government and media, in assisting in understanding the nature, size and development of the organic industry in Australia. Supply chain development has been hindered over many years by a lack of basic information about volumes, seasonality, continuity and quality, not only making it difficult for potentially new members of industry to feel confident about investing in organic, however also likely to cause overseas buyers to look for other countries with more comprehensive industry information. The report is an important base research document required by any growing industry. It has been commissioned by Biological Farmers of Australia (BFA), and has been carried out independently by the University of New England’s Organic Research Group. The report has the financial support of major sponsor Westpac Bank, all State Governments in Australia as well as many dedicated industry businesses

Evaluation of Faraday-shielded Stix coils for ion cyclotron resonance heating of a plasma Technical report no. 3

Faraday-shielded Stix coil evaluation including electric field waveform for ion cyclotron resonance heating of plasm

The Power of Non-Determinism in Higher-Order Implicit Complexity

We investigate the power of non-determinism in purely functional programming languages with higher-order types. Specifically, we consider cons-free programs of varying data orders, equipped with explicit non-deterministic choice. Cons-freeness roughly means that data constructors cannot occur in function bodies and all manipulation of storage space thus has to happen indirectly using the call stack. While cons-free programs have previously been used by several authors to characterise complexity classes, the work on non-deterministic programs has almost exclusively considered programs of data order 0. Previous work has shown that adding explicit non-determinism to cons-free programs taking data of order 0 does not increase expressivity; we prove that this - dramatically - is not the case for higher data orders: adding non-determinism to programs with data order at least 1 allows for a characterisation of the entire class of elementary-time decidable sets. Finally we show how, even with non-deterministic choice, the original hierarchy of characterisations is restored by imposing different restrictions.Comment: pre-edition version of a paper accepted for publication at ESOP'1

On a tropicalization of planar polynomial ODEs with finitely many structurally stable phase portraits

Recently, concepts from the emerging field of tropical geometry have been used to identify different scaling regimes in chemical reaction networks where dimension reduction may take place. In this paper, we try to formalize these ideas further in the context of planar polynomial ODEs. In particular, we develop a theory of a tropical dynamical system, based upon a differential inclusion, that has a set of discontinuities on a subset of the associated tropical curve. The development is inspired by an approach of Peter Szmolyan that uses the connection of tropical geometry with logarithmic paper. In this paper, we define a phaseportrait, a notion of equivalence and characterize structural stability. Furthermore, we demonstrate the results on several examples, including a(n) (generalized) autocatalator model. Our main result is that there are finitely many equivalence classes of structurally stable phase portraits and we enumerate these ($15$ in total) in the context of the generalized autocatalator model. We believe that the property of finitely many structurally stable phase portraits underlines the potential of the tropical approach, also in higher dimension, as a method to obtain and identify skeleton models in chemical reaction networks in extreme parameter regimes

Peaked sloshing in a wedge container

Finite-amplitude free-surface flow in a wedge container is investigated analytically. We study a motionless standing wave of pure potential-flow acceleration with maximal amplitude where its right-angle surface peak falls from rest. The nonlinear free-surface conditions are satisfied by a family of flows where the chosen initial acceleration field is governed by one single dipole plus its three image dipoles. Streamlines and isobars are plotted, with the free surface as the zero-pressure isobar. The key geometric parameters are tabulated for each case, supplied with force calculations for an upright wedge container. The present approach is assessed against established eigenfunctions for linearized standing waves in a wedge container. The present dipole flows constitute a much richer family of peaked free sloshing shapes than the classical Fourier modes of free oscillation.acceptedVersio