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This paper presents a comprehensive substance flow analysis (SFA) of phosphorus (P) for a six-year period (2008–13) in Gippsland, a key agricultural region of Australia with high economic and environmental significance. The analysis has revealed that around 71% (10,904 t) of the mean annual total inflow of P was stored in this region. This finding is different from other published regional scale SFAs, where more than 50% of the P in annual total inflow eventually left the region. Per capita P inflow in Gippsland is also found substantially higher compared to available SFAs. In Gippsland, the annual inflow of P primarily occurred as commercial fertilizer (66% or 10,263 t) and livestock feed (29% or 4443 t), and the outflow mainly occurred as livestock products (94% or 4181 t); while the majority (66% or 7218 t) of the P storage occurred in soils of the livestock farming area. A comparative analysis of the magnitude of P flow in different subsystems indicates that more than 80% of the annual total inflow, outflow, and storage of P in this region is associated with the livestock (mainly dairy and meat cattle) farming subsystem. For the Gippsland region as a whole and almost all subsystems, significant annual variations in the magnitudes of P inflow, outflow, storage and internal flow have been observed. Between 2008 and 2013, both the annual total inflow (mainly as commercial fertilizer) and the annual total storage (mainly in soils) of P in this region showed a substantial decrease (41% and 54% of the 2008 level, respectively), while the annual total outflow (mainly as livestock and crop products) remained nearly the same, indicating an improvement towards sustainable P management. Despite such a positive sign, there is still adequate room for improvement. This analysis indicates that over the study period, about 65,424 t P were accumulated (mainly as soil storage) that is approximately six times the mean annual P inflow as commercial fertilizer in this region; while approximately 3241 t P lost as soil erosion and runoff, indicating substantial adverse economic and environmental implications. Based on the findings of the current analysis, this paper outlines a wide range of policy and management interventions to reduce the downstream loss of P and other nutrients as well as the region's dependency on imported commercial fertilizers and grain based feed. This paper also presents new criteria for data quality analysis and a set of P concentration data of various materials that could be readily utilized in future SFAs of P at any geographical scale. This paper suggests that considering the inter-annual variations in P flow as assessed in this SFA, future research should focus on identifying the influence of socio-environmental, technological and political factors on the magnitude P flow in Gippsland. [ABSTRACT FROM AUTHOR]

Queensland grazing industries operate in one of the world’s most variable climates and face enormous challenges to achieve profitability and sustainability. To assist grazing enterprises, the Queensland Government has developed an operational online information system – FORAGE, to facilitate best management practice for grazing land. The FORAGE system provides land managers with property-scale information relating to rainfall, ground cover, soil erodibility, land types, tree density, seasonal climate outlooks and pasture growth simulated using the GRASP grazing system model. This information is site-specific and tailored to facilitate on-ground management decisions common to Queensland grazing enterprises. The FORAGE system makes complex remotely-sensed data, information from a range of databases and pasture growth models more accessible and relevant to land managers. This paper describes the structure, resources (e.g. software, databases and models), information generating processes, delivery mechanisms and information products of the FORAGE system. [ABSTRACT FROM AUTHOR]

Integrated crop-livestock systems (ICL) have played an important role in human civilisation and have dominated the broadacre agricultural production system in the wheat-sheep zone of Australia. Over the past couple of decades, an increase in grain prices and decline in wool prices have led to the expansion of cropping into the high rainfall zone (HRZ) in southern Australia. While there has been a great deal of research into integrated crop-livestock systems for the medium to low rainfall environments in the wheat-sheep zone, there is much less information and many challenges confronting farmers to effectively integrate crops into the grazing systems in the high rainfall zone due to climatic and environmental differences and the complexity of the systems in Australia. This paper reviews the benefits of integrated crop-livestock systems and the challenges in implementing and managing these systems based on current Australian and international knowledge. The concept, types and terminology of integrated crop-livestock systems are discussed to provide greater clarity. Plant species, particularly annual and perennial legumes, are reviewed to find species with potential for use in integrated crop-livestock systems. Major gaps and opportunities for further research and development are identified, and recommendations proposed for developing effective integrated crop-livestock systems for the HRZ. These include: 1) Targeted R&D on ICL systems in the HRZ of southern Australia assisted with information from and outside Australia; 2) Biophysical and bio-economic modelling using current knowledge from the HRZ and other environments to guide future research; 3) Studies on N fixation, transfer and losses to develop strategies to balance N cycling and reduce N losses; 4) Development of compatible species/cultivars for ICL systems in the HRZ; 5) Management of waterlogging through ICL in the HRZ; 6) Effective stubble management to minimise the negative impact on crops and pastures; 7) Integrated research on grain yield reduction in crop-pasture intercropping, a potentially major type of ICL systems in the HRZ; and 8) Effective control of weeds, pests and diseases in ICL systems for the HRZ. [ABSTRACT FROM AUTHOR]

Abstract: In most countries, owner responsibility exists under Common Law to manage and maintain dams according to current standards. However, farm dam safety in Australia is being flouted and the sustainability of farming businesses compromised because of the potential and severe consequences of dam failure. This paper explores management and policy issues associated with safety of farm dam water storage through a comparison of developments in two Australian states against international benchmarks. Historical review and a longitudinal study over a 12-year period provides the basis for case analysis and demonstrates the application of the benchmarked model policy selection guidelines. Research results show South Australia is lagging international best practice in a number of ways whilst Tasmania provides leadership. The contribution of this paper is a regulatory mix analysis approach, incorporating a cost-effective spillway safety engineering/accounting tool, developed and demonstrated through Australian case studies, that can be applied by any jurisdiction wanting to check and/or improve its farm dam safety management and provide a clearer analysis of the social and environmental costs and threats associated with on-farm dam safety issues. [ABSTRACT FROM AUTHOR]

Abstract: Efficient mechanisation is a major factor underlying the high productivity and low cost of most Australian crop production systems. Efficiency has generally been associated with greater work rates, achieved by using equipment of greater power and weight. This trend has continued until very recently, despite a reduction in tillage for weed control. Scientists have warned of erosion and soil structural degradation caused by tillage and traffic, but tillage, rather than field traffic was seen as the major problem, and reduction of tillage as the solution. Reduced tillage has provided major benefits, but adoption has occurred slowly and sustained zero tillage is still rare, except in controlled traffic farming systems. The first part of this paper presents research evidence of the direct cost, practical impact and long-term effects of wheel traffic on cropped soil. Direct cost is associated with the energy requirements of disturbing wheeled soil. Practical impact occurs as a result of the lost opportunities and additional operations associated with wheel ruts. Long-term productivity and environmental impact occur because wheel traffic reduces plant available water and increases runoff and erosion. In controlled traffic all equipment wheels are restricted to compacted permanent traffic lanes, so that soil in the crop beds and traffic lanes can be managed respectively for optimum cropping and optimum trafficability. Controlled traffic farming recognizes the symbiosis between controlled traffic and zero tillage in providing opportunities for more productive and sustainable farming of soil uncompromised by wheel effects. The beneficial effects of controlled traffic have been demonstrated in widely different soils and mechanisation systems (e.g. Australia and China), and it has been vigorously advocated in both the USA and Europe, but large-scale adoption has been rare. The second part of this paper discusses cropping system response to controlled traffic farming, and the program which led to large-scale adoption in Australia. This happened first in extensive grain production, but adoption has since occurred in many Australian farming systems, supported by the availability of high-precision field guidance systems and a greater range of compatible equipment. Controlled traffic farming reduces soil degradation and the energy requirements of cropping. It is also more productive, and its practicality and economic viability have been clearly demonstrated in enthusiastic farmer adoption, and the formation of an Australian Controlled Traffic Farming Association. [Copyright &y& Elsevier]

Abstract: In Western Australia, farmer-led farming systems groups (grower groups) are actively forming partnerships with other grower groups, researchers and private industry. As the broadacre grain and livestock farming system increases in complexity, existing partnerships may not be adequate and a new approach is needed. An organisational form that is designed to work in such complexity is the ‘network’. Grower group networks are able to create an environment where shared understanding and/or collective action is used to achieve outcomes where there are no readily available solutions. In 2002, the Grower Group Network project was established to support grower groups in a network to provide their members with access to the latest information and research. The organisation of farming systems groups into networks has made them more accessible and relevant to researchers. In this paper, a description of the role of grower groups and grower group networks can play in research projects is outlined, illustrated by case studies of successful partnerships. The most successful projects occur when farming systems groups and research providers develop and implement a new project together. Grower group networks are also a very effective means of delivering research outcomes as they can provide researchers with opportunities for impact well beyond partnerships with one or two grower groups. The paper concludes with a description of the future challenges for grower group networks. [Copyright &y& Elsevier]

Abstract: The International Panel on Climate Change (IPCC) predicts an increase of 0.2 °C per decade for the next two decades in global temperatures and a rise of between 1.5 and 4.5 °C by the year 2100. Related to the increase in world temperatures is the increase in Greenhouse Gases (GHGs) which are primarily made up of carbon dioxide (CO2), nitrous oxide (N2O), methane (CH4) and fluorinated gases. In 2004, the GHGs from agriculture contributed 14% of the overall global GHGs made up mainly of methane (CH4) and nitrous oxide (N2O) emissions. In Australia, the dominant source of CH4 and N2O emissions for the year ending June 2012 was found to be from the agricultural sector. With the recent introduction of the Clean Energy Act 2011, the agricultural sector of Australia is expected to develop appropriate GHG mitigation strategies to maintain and improve its competitiveness in the green commodity market. This paper proposes the use of Integrated Spatial Technologies (IST) framework by linking Life Cycle Assessment (LCA), Remote Sensing (RS) and Geographical Information Systems (GIS). The IST approach also integrates and highlights the use of Cleaner Production (CP) strategies for the formulation and application of cost-effective GHG mitigation options for grain production in Western Australia (WA). In this study, the IST framework was tested using data from an existing study (the baseline study) and two mitigation options. The analysis results revealed production and use of fertiliser as the “hotspot”, and for mitigation purposes was replaced with pig manure in option 1, whereas option 2 emphasised crop rotation system/s. [Copyright &y& Elsevier]

Abstract: World population growth, changing diets and limited opportunities to expand agricultural lands will drive agricultural intensification in the decades ahead. Concerns about the reliance of past agricultural intensification on non-renewable resources, about its negative impacts on natural resources both on and off farm and on greenhouse gas emissions, provide an imperative for future agricultural intensification to become ecologically efficient. We define ecological intensification of agriculture (EIA) as: producing more food per unit resource use while minimising the impact of food production on the environment. Achieving it will require increased precision in the use of inputs and reduction in inefficiencies and losses. It will also require a more holistic view of farming, going beyond efficiencies of single inputs into a single field in a single season to consideration of efficiencies of whole systems over decades. This paper explores the ecological intensification issues facing agricultural production in Australia where opportunities for agricultural intensification are centred on more efficient use of limited and unreliable water resources in both dryland and irrigated agriculture. Ecological efficiencies can be achieved by better matching the supply of nutrients to crops’ requirements both temporally and spatially. This has the added benefit of minimising the opportunities for excessive nutrients to impact on soil health (acidity and dryland salinity) and water quality (pollution of groundwater and eutrophication of lakes and rivers). Opportunities for ecologically efficient intensification are also identified through better integration of crop and livestock enterprises on mixed crop–livestock farms. We define nine desirable attributes of an EIA system: (1) increased agricultural production; (2) efficient use of limited resources; (3) minimal impact on global warming; (4) minimal negative on-site impacts; (5) minimal negative off-site impacts; (6) minimal risk and maximum resilience; (7) preservation of biodiversity in agriculture; (8) preservation of biodiversity in nature and; (9) positive social outcomes. We focus on four technologies and production systems emerging in Australian agriculture: climate risk management; precision agriculture; crop–livestock integration and deficit irrigation. For each of these systems we identify how well they are likely to match the nine desirable attributes of an EIA system. While it seems unlikely that any single technology can satisfy all nine desirable attributes, there is hope that in combination emerging and future technologies will progress Australian agriculture towards greater productivity and ecological efficiency. [Copyright &y& Elsevier]

Abstract: To feed a growing world population in the coming decades, agriculture must strive to reduce the gap between the yields that are currently achieved by farmers (Ya) and those potentially attainable in rainfed farming systems (Yw). The first step towards reducing yield gaps (Yg) is to obtain realistic estimates of their magnitude and their spatial and temporal variability. In this paper we describe a new yield gap assessment framework. The framework uses statistical yield and cropping area data, remotely sensed data, cropping system simulation and GIS mapping to calculate wheat yield gaps at scales from 1.1km cells to regional. The framework includes ad hoc on-ground testing of the calculated yield gaps. This framework was applied to wheat in the Wimmera region of Victoria, Australia. Estimated Yg over the whole Wimmera region varied annually from 0.63 to 4.12Mgha−1with an average of 2.00Mgha−1. Expressed as a relative yield (Y %) the range was 26.3–77.9% with an average of 52.7%. Similarly large spatial variability was described in a Wimmera yield gap map. Such maps can be used to show where efforts to bridge the yield gap are likely to have the biggest impacts. Bridging the exploitable yield gap in the Wimmera region by increasing average Y % to 80% would increase average annual wheat production from 1.09Mtonnes to 1.65Mtonnes. Model estimates of Yw and Yg were compared with data from crop yield contests, experimental variety trials, and on-farm water use and yields. These alternative approaches agreed well with the modelling results, indicating that the proposed framework provided a robust and widely applicable method of determining yield gaps. Its successful implementation requires that: (1) Ya as well as the area and geospatial distribution of wheat cropping are well defined; (2) there is a crop model with proven performance in the local agro-ecological zone; (3) daily weather and soil data (such as PAWC) required by crop models are available throughout the area; and (4) local agronomic best practice is well defined. [Copyright &y& Elsevier]

Abstract: The shift to agricultural systems involving no-tillage from those based on multiple cultivations has required decades and is ongoing. This paper examines the enabling factors for the adoption of no-tillage cropping systems including the demand-induced innovation by farmers and agricultural engineers, enabling agronomic technologies such as herbicides and crop disease resistance, extension processes, and economic influences. The first section draws upon existing studies from grain producing regions to demonstrate the multiple dimensions and lags involved in achieving such a major change in agricultural practice. In the second section, we identify and quantify the major agronomic and socio-economic drivers of no-tillage adoption rates in Australia. Analysis of data collected from 1170 grain growers across 19 Australian grain growing regions is used to characterise current no-tillage adoption by regions and the its extent of use. Cumulative adoption curves show that the proportion of farmers using at least some no-tillage has started to plateau near 90% in several regions, while in others, a much lower proportion of farmers have adopted or expect to adopt in the medium term future. Many Australian growers use some no-tillage but maintain a high degree of flexibility in their approach to soil disturbance and respond to economic and seasonal drivers. The results suggest that the same extension and diffusion processes that have led to the current high adoption by farmers in some regions may not lead to further adoption of no-tillage in all regions. Soil erosion, for example, was an important motivating factor early in the development of no-tillage but is not found to be a major factor differentiating adopters and non-adopters in the later stages of technology diffusion. Increasingly, the constraint to more extensive use of no-tillage is the extent of use by existing adopters. Factors relating to disease risks and weed management are identified as important. The long and knowledge intensive innovation process for no-tillage systems has led to remarkable changes in agricultural landscapes. It is an ongoing process that continues in later-adopting regions and in sustaining extensive use. [Copyright &y& Elsevier]

Abstract: This paper presents a novel approach for automatic segmentation and object detection of tree crowns in airborne images captured from a low-flying Unmanned Aerial Vehicle (UAV) in ecology monitoring applications. Cost effective monitoring in these applications necessitates the use of vision-band-only imaging on the UAV platform; the reduction in spectral resolution (compared to multi- or hyper-spectral imaging) is balanced by the high spatial resolution available (20cm/pixel) from the low-flying UAV, when compared to existing satellite or manned-aerial survey data. Our approach to object detection thus uses both geometry and appearance information (through the use of tree shape and shadow information) in addition to spectral information to help accurately distinguish tree crowns within our application. A predictive geometric template for tree detection is constructed using on-board UAV navigation data, sun lighting information and information about the geometry of the target crown. A two-stage detection algorithm is then used to segment tree crowns based on spectral (colour) information convolved with information from the predictive template. Results of our approach are presented using airborne image data collected from a fixed-wing UAV during a weed monitoring and mapping mission over farmland in West Queensland, Australia. [Copyright &y& Elsevier]

Abstract: Policy makers in the agricultural sector are confronted with challenges which might drive land use change and ultimately agricultural profitability to a substantial degree. The challenges include questions around climate variability, demographic changes, use of land for bio-fuel production and ensuring an increase in food production. As profitability triggers many agri-business decisions, knowledge about the existing socio-economic landscape and the economic profile of a region as well as potential impacts on profits provides useful contextual information when agricultural policies are designed. Given the upcoming challenges and their associated uncertainties, it is important to ensure that a map of agricultural profit can be reproduced in a scenario and simulation setting which will allow exploring uncertainties around the impacts on agricultural profits as well. There is however currently no flexible system in operation which allows for a consistent update of a map of agricultural profits in Australia or elsewhere. This paper describes a process that has been developed to produce a map of agricultural profit for Australia for the year 2005/2006. The process involves a complex data architecture that accounts for heterogeneous information that is collected by a variety of institutions across different scales. All information can be comfortably queried and query results can be forwarded for immediate processing and subsequent visualisation in a geographic information system (GIS). To facilitate the production of profit maps in the future, the system provides flexibility regarding an update of new economic information but it can also be linked to maps that show an updated distribution of land use. A map of agricultural profit on a large scale and regular updates thereof will help understand profit trends in time and across space. It will help identifying regions that have a lower economic profile and will inform decisions regarding the design of regulatory policies. As these maps are developed using national scale data, we do not recommend using the results at the farm level but we suggest using separate catchment scale profit assessments to calibrate the national scale profit map. The proposed system is well suited to be used in various land use management and economic scenarios and will represent a step forward regarding a scenario impact assessment on agricultural profits. It will also help understand the economic benefit of land use on a large scale. [Copyright &y& Elsevier]

Abstract: This paper examines the idea that plasticity in farm management introduces resilience to change and allows farm businesses to perform when operating in highly variable environments. We also argue for the need to develop and apply more integrative assessments of farm performance that combine the use of modelling tools with deliberative processes involving farmers and researchers in a co-learning process, to more effectively identify and implement more productive and resilient farm businesses. In a plastic farming system, farm management is highly contingent on environmental conditions. In plastic farming systems farm managers constantly vary crops and inputs based on the availability of limited and variable resources (e.g. land, water, finances, labour, machinery, etc.), and signals from its operating environment (e.g. climate, markets), with the objective of maximising a number of, often competing, objectives (e.g. maximise profits, minimise risks, etc.). In contrast in more rigid farming systems farm management is more calendar driven and relatively fixed sequences of crops are regularly followed over time and across the farm. Here we describe the application of a whole farm simulation model to (i) compare, in silico, the sensitivity of two farming systems designs of contrasting levels of plasticity, operating in two contrasting environments, when exposed to a stressor in the form of climate change scenarios;(ii) investigate the presence of interactions and feedbacks at the field and farm levels capable of modifying the intensity and direction of the responses to climate signals; and (iii) discuss the need for the development and application of more integrative assessments in the analysis of impacts and adaptation options to climate change. In both environments, the more plastic farm management strategy had higher median profits and was less risky for the baseline and less intensive climate change scenarios (2030). However, for the more severe climate change scenarios (2070), the benefit of plastic strategies tended to disappear. These results suggest that, to a point, farming systems having higher levels of plasticity would enable farmers to more effectively respond to climate shifts, thus ensuring the economic viability of the farm business. Though, as the intensity of the stress increases (e.g. 2070 climate change scenario) more significant changes in the farming system might be required to adapt. We also found that in the case studies analysed here, most of the impacts from the climate change scenarios on farm profit and economic risk originated from important reductions in cropping intensity and changes in crop mix rather than from changes in the yields of individual crops. Changes in cropping intensity and crop mix were explained by the combination of reductions in the number of sowing opportunities around critical times in the cropping calendar, and to operational constraints at the whole farm level i.e. limited work capacity in an environment having fewer and more concentrated sowing opportunities. This indicates that indirect impacts from shifts in climate on farm operations can be more important than direct impacts from climate on the yield of individual crops. The results suggest that due to the complexity of farm businesses, impact assessments and opportunities for adaptation to climate change might also need to be pursued at higher integration levels than the crop or the field. We conclude that plasticity can be a desirable characteristic in farming systems operating in highly variable environments, and that integrated whole farm systems analyses of impacts and adaptation to climate change are required to identify important interactions between farm management decision rules, availability of resources, and farmer''s preference. [Copyright &y& Elsevier]

Abstract: Coal fired electricity is a major factor in Australia’s greenhouse gas emissions (GHG) emissions. The country has adopted a mandatory renewable energy target (MRET) to ensure that 20% of electricity comes from renewable sources by 2020. In order to support the MRET, a market scheme of tradable Renewable Energy Certificates (RECs) has been implemented since 2001. Generators using biomass from eligible sources are able to contribute to GHG emission reduction through the substitution of coal for electricity production and are eligible to create and trade RECs. This paper quantifies the potential biomass resources available for energy generation from forestry and agriculture in the Green Triangle, one of the most promising Australian Regions for biomass production. We analyse the cost of electricity generation using direct firing of biomass, and estimate the required REC prices to make it competitive with coal fired electricity generation. Major findings suggest that more than 2.6 million tonnes of biomass are produced every year within 200 km of the regional hub of Mount Gambier and biomass fired electricity is viable using feedstock with a plant gate cost of 46 Australian Dollars (AUD) per tonne under the current REC price of 34 AUD per MWh. These findings are then discussed in the context of regional energy security and existing targets and incentives for renewable energies. [Copyright &y& Elsevier]

Abstract: Public expectations of soil management are gradually expanding beyond traditional primary production requirements to include diverse ecosystem services. In Australia, as in many other countries, the accommodation of these new expectations will require shifts in the practice of private land managers. In turn, this may require public intervention and the expenditure of public funds. However, public net benefits from soil management interventions are rarely established, in part due to a lack of understanding of the conceptual links between management changes, soil health, and associated services and benefits. This paper uses an ecosystem services-based approach to examine these links from an Australian perspective. Entrenchment of the popular soil health concept in field-based assessments of agricultural production potential was found to limit the concept''s applicability to questions of broader public benefit. Without expanding soil health to include more ecological indicators, the concept risks remaining peripheral to contemporary visions of multiple-outcome soil management in Australia. Conceptual and case study links were examined between soil properties and processes, soil-based services, and private and public net benefits. In this framework, benefits were produced from services, and were considered a more tangible point for public understanding and valuation than services. The qualitative case study highlighted many knowledge gaps relating to non-agricultural services and benefits from soils, particularly in the scaling-up of sub-paddock measurements, and in the form and constancy of relationships among services and benefits. Criteria for identifying priority public benefits from soil management were examined, namely, likelihood, degree, consequence, scale, direction, time lag, and valuation. Assumptions about these criteria require rigorous testing so that the what, where, when, and how of public benefits from changed soil management can be more clearly defined. [Copyright &y& Elsevier]

Abstract: We discuss the role and characteristics of water markets in Australia in facilitating efficient water allocation. Administrative, regulatory and/or political barriers to effective functioning of water markets are reviewed with a focus on the southern Murray-Darling Basin (MDB) region of Australia. A mathematical model is developed to estimate the costs of existing restrictions and the benefits from potential changes in water markets (e.g., removing barriers in temporary water markets). The modelling results reveal that expanding trade leads to an increase in mean annual net returns from AU $2502 million to AU $2590 million (i.e., an increase of AU $88 million). When the current volume restrictions, exchange rates, and trading charges are accounted for, mean annual net returns reduced from AU $2590 million to AU $2573 million (i.e., a reduction of AU $17 million). The exclusion of any of the three southern MDB states from the interstate water trading imposes significant costs. If South Australia, New South Wales or Victoria withdraws from the water market, net returns are reduced by AU $27 million, AU $31 million and $63 million, respectively. The paper outlines the policy implications of strategies to remove market barriers and to facilitate efficient and effective water trading. [Copyright &y& Elsevier]

Abstract: Woody regrowth is extensive on abandoned agricultural lands and developed pastures worldwide. Regrowth is actively controlled in working pastures, but it could be managed to offset greenhouse gas emissions from agriculture and other emitting industries with supplementary benefits for biodiversity conservation. This paper explores the case of Brigalow regrowth in the extensive pastoral landscape of north-eastern Australia. By synthesising current ecological knowledge with relevant socio-economic and policy considerations, it examines the potential of the Brigalow regrowth ecosystem to provide dual carbon/biodiversity benefits. Brigalow regrowth sequesters large amounts of carbon, especially when compared to other ecosystems from similar sub-humid climates. In addition, restoring regrowth is likely to have benefits for a wide range of native flora and fauna, including the endangered bridled nailtail wallaby. However, there are knowledge gaps relating to the landscape ecology of Brigalow regrowth and the impacts of management and climate change on carbon/restoration potential. Also, a conflict exists between short-term carbon sequestration and long-term restoration goals and we suggest a role for restoration thinning to resolve this. Regional demand for high biomass regrowth as a carbon offset is likely to be high but ambiguities in carbon policy threaten to diminish the use of natural regrowth for reforestation projects. [Copyright &y& Elsevier]

Abstract: Secondary salinisation is a growing problem in Western Australia, with 1.1Mha of agricultural and public land now affected to some extent. During the 1980s and early 1990s it was widely believed that agroforestry offered one of the best hopes for reducing the area at risk from salinisation while improving the productivity of conventional agricultural enterprises and providing new sources of income to landholders. This paper details the hydrogeology, tree water use and the productivity of Eucalyptus globulus, crops and pastures in an agroforestry system on the south coast of Western Australia with deep sandy soils and rising groundwater. The tree-belts directly occupied 10% of the catchment and the lateral spread of outer tree roots meant recharge was effectively eliminated over 20% of the catchment. However, groundwater at the site continued to rise for 13 years after the trees were planted. Sapflow and tree growth measurements showed that the trees did not access the brackish groundwater (>500mg/L) present over most of the site. Consequently, tree growth was relatively poor (5m3/ha/yr for inner trees) and the estimated economic returns from pulpwood production were less than from agriculture. While the outer tree rows grew at 8 times the rate of inner rows, this was at the expense of reduced crop and pasture growth in the adjacent 15–20m wide competition zone (CZ). If the area of the CZ where agricultural production was less than breakeven is considered, then the outer tree rows grew at a similar rate (expressed on an area basis) as the inner rows. This suggests there was no economic advantage in growing pulpwood in belts rather than blocks at this site. Thinning the trees to 125stems/ha allowed improved crop and pasture production and reduced wind erosion in the CZ, and facilitated greater growth rates of the remaining trees. It remains to be determined whether increased economic returns from the trees will compensate for the cost of thinning and pruning. This study has shown that E. globulus is not a suitable agroforestry tree species for medium rainfall sites with deep sands and brackish groundwater, other tree species may be more suited to these sites and achieve better economic and hydrological outcomes for landholders. [Copyright &y& Elsevier]

Abstract: The current agricultural systems of broad areas of Australia are unsustainable, with large projected increases in salinization, decreases in water quality, wind erosion, and losses of biodiversity. It is well known that these problems can be partially resolved by farmland reforestation; however, a major issue is financing the scale of activity required. The international response to global warming, the United Nations Framework Convention on Climate Change and its Kyoto Protocol, includes provisions that enable greenhouse sinks (sequestration of carbon in soils and vegetation) to be used by parties to fulfil their obligations. The Kyoto Protocol also allows for trading in emission reductions, and this opens the possibility that investment in carbon sinks may help underwrite broader natural resource management objectives. This paper examines the possibilities for improved land management in Western Australia arising from the development of carbon sinks by considering: (a) the likelihood of a carbon market developing and the likely depth of that market as a result of current national and international policies, (b) the data available to provide estimates on different types of sinks, and (c) the likely benefits of wide-scale sink investment. It was estimated that the total amount of carbon that could be sequestered by reforesting 16.8Mha of cleared farmland is 2200Mt CO2-e, and between 290 and 1170Mt CO2-e by destocking 94.8Mha of rangelands. There were insufficient data to produce estimates of sequestration following changes in tillage practice in cropping systems or the revegetation of already salinized land. We conclude that carbon sinks are only likely to become profitable as a broad-scale stand-alone enterprise when carbon prices reach AUD$15/t CO2-e, with this threshold value varying with carbon yield and project costs. Below this price, their value can be significant as an adjunct to reforestation schemes that are aimed at providing other products (wood, pulp, bioenergy) and land and water conservation benefits. Irrespective of this, carbon sinks provide an opportunity to both sequester carbon in a least-cost fashion and improve soil and watershed management. [Copyright &y& Elsevier]

Abstract: The Moore Catchment, which lies to the north of Perth in Western Australia, suffers from a number of problems related to water management. Farmers want to manage salinity and waterlogging problems through the use of drains, but this has possible negative off-farm impacts on both the environment and flood risk. Views on responsibilities for managing water within the catchment differ between farmers, local communities and government agencies. This paper reports the results from surveys of attitudes towards catchment management, for two community groups: residents of Perth and residents of rural towns in the catchment. These surveys elicited general attitudes towards the environment and agriculture, and views on responsibilities for managing the catchment. It also included a choice modelling section, where the attributes under consideration included the area of land under salt and trees, ecological risks to off-farm wetlands and risk of flooding, farm incomes and personal financial contributions to a management fund. Preliminary results indicate that residents of both rural towns and Perth are willing to pay to avoid damage to the natural environment, both on and off-farm, as well as the risk of flooding. Perhaps more surprisingly, whether farmers’ incomes were being negatively affected in a choice set has a very strong impact on the choice made. [Copyright &y& Elsevier]

There is growing evidence of spillover effects to developed countries from the plant genetic improvement work of international agricultural research centers (IARCs) that nevertheless benefit the targeted developing countries. This paper examines the modes in which such spillover effects from IARCs to developed countries have an impact on the overall benefits from the IARC system. A case study of production spillovers in Australia from ICARDA’s work indicates a shift of benefits for the rest of the world from producers to consumers, with overall benefits to the rest of the world marginally higher in the presence of spillovers. These findings suggest spillovers to developed countries can enhance the impacts of the IARCs on developing countries though they can affect the distribution of benefits received. [Copyright &y& Elsevier]

FARMSCAPE (Farmers'', Advisers'', Researchers'', Monitoring, Simulation, Communication And Performance Evaluation) is a program of participatory research with the farming community of northeast Australia. It initially involved research to explore whether farmers and their advisers could gain benefit from tools such as soil characterisation and sampling, climate forecasts and, in particular, simulation modelling. Its current focus is facilitating the implementation of commercial delivery systems for these same tools in order to meet industry demand for their access. This paper presents the story of what was done over the past decade, it provides performance indicators of impact, it reflects on what was learnt over this period and it outlines where this research is likely to head in the future.Over the past 10 years, the FARMSCAPE team employed a Participatory Action Research approach to explore whether farmers could value simulation as a decision support tool for managing their farming system and if so, could it be delivered cost-effectively. Through farmer group engagement, on-farm trials, soil characterisation, monitoring of crops, soils and climate, and sessions to apply the APSIM systems simulator, FARMSCAPE represented a research program on decision support intervention. Initial scepticism by farmers and commercial consultants about the value of APSIM was addressed by testing its performance both against measured data from on-farm trials and against farmers'' experiences with past commercial crops. Once this credibility check was passed, simulation sessions usually evolved into participants interactively inquiring of the model the consequence of alternative management options. These ‘What if’ questions using APSIM were contextualised using local climate and soil data and the farmer''s actual or proposed management rules.The active participation of farmers and their advisers, and working in the context of their own farming operations, were the key ingredients in the design, implementation and interpretation of the FARMSCAPE approach to decision support. The attraction of the APSIM systems simulator to farmers contemplating change was that it allowed them to explore their own system in a manner equivalent to learning from experience. To achieve this, APSIM had to be credible and flexible. While direct engagement of farmers initially enabled only a limited number of beneficiaries, this approach generated a commercial market for timely and high quality interactions based on soil monitoring and simulation amongst a significant sector of the farming community. Current efforts are therefore focused on the training, support and accreditation of commercial agronomists in the application of the FARMSCAPE approach and tools.The FARMSCAPE approach to decision support has come to represent an approach to guiding science-based engagement with farm decision making which is being tested nationally and internationally. [Copyright &y& Elsevier]