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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]