Mahabubur Mollah

Copper Fungicide Residues in Australian Vineyard Soils

Copper (Cu) concentrations were measured in Australian vineyard soils to assess the extent and magnitude of Cu accumulation resulting from the use of Cu-based fungicides and to indicate the likely risks to long-term soil fertility. Soil samples were collected from 98 vineyards across 10 grape-growing regions of Australia and analyzed for total Cu concentrations. Ninety-six percent of vineyards surveyed had elevated Cu concentrations in soil compared to the background Cu concentrations in nearby soil in its native state. Concentrations of total B, Co, Cr, Pb, and Zn were similar to background concentrations and below reported toxicity guideline values. Cu concentrations in Australian vineyard soils were generally much lower (6-150 mg kg (-1)) than those reported in the soils of vineyards in parts of Europe (i.e., 130-1280 mg kg (-1)). Concentrations of total Cu were generally below those concentrations reported to cause lethal effects to soil invertebrates; however, Cu exceeded concentrations known to cause sublethal effects (i.e., inhibit growth, affect reproduction, induce avoidance behavior) to those (or related) invertebrates.

Australian grains free-air carbon dioxide enrichment (AGFACE) facility: design and performance

The AGFACE project commenced in June 2007 at Horsham (36°45′07″S, 142°06′52″E; 127 m elevation), Victoria, Australia. Its aim is to quantify the interactive effects of elevated atmospheric carbon dioxide concentration (e[CO2]), nitrogen, temperature (accomplished by early and late sowing times), and soil moisture on the growth, yield, and water use of wheat (Triticum aestivum L.) under Australian conditions. The main engineering goal of the project was to maintain an even temporal and spatial distribution of carbon dioxide (CO2) at 550 μmol/mol within AGFACE rings containing the experimental treatments. Monitoring showed that e[CO2] at the ring-centres was maintained at or above 90% of the target (495 μmol/mol) between 93 and 98% of the operating time across the 8 rings and within ±10% of the target (495–605 μmol/mol) between 86 and 94% of the time. The carbon dioxide concentration ([CO2]) measured inside the rings declined non-linearly with increasing distance downwind of the CO2 source and differed by 3–13% in concentration between the two canopy heights in each ring, but was not affected by wind speed or small variations in [CO2] at the ring-centres. The median values for model-predicted concentrations within the inner 11-m-diameter portion of the rings (>80% of the ring area) varied between 524 and 871 μmol/mol but remained close to target near the centres. The design criteria adopted from existing pure CO2 fumigating FACE systems and new ideas incorporated in the AGFACE system provided a performance similar to its equivalent systems. This provides confidence in the results that will be generated from experiments using the AGFACE system.

Understand distribution of carbon dioxide to interpret crop growth data: Australian grains free-air carbon dioxide enrichment experiment

Carbon dioxide (CO2) is the most important greenhouse gas, predicted to increase globally from currently 386 to 550 μmol mol–1 by 2050 and cause significant stimulation to plant growth. Consequently, in 2007 and 2008, Australian grains free-air carbon dioxide enrichment (AGFACE) facilities were established at Horsham (36°45′07″S lat., 142°06′52″E long., 127 m elevation) and Walpeup (35°07′20″S lat., 142°00′18″E long., 103 m elevation) in Victoria, Australia to investigate the effects of elevated CO2, water supply and nitrogen fertiliser on crop growth. Understanding the distribution patterns of CO2 inside AGFACE rings is crucial for the interpretation of the crop growth data. In the AGFACE system, the engineering performance goal was set as having at least 80% of the ring area with a CO2 concentration [CO2] at or above 90% of the target concentration at the ring-centre for 80% of the time. The [CO2] was highly variable near the ring-edge where CO2 is emitted and declined non-linearly with the distance downwind and wind speeds. Larger rings maintained the target [CO2] of 550 μmol mol–1 at the ring-centres better than the smaller rings. The spatial variation of [CO2] depended on ring size and the gap between fumigation and canopy heights but not on wind speeds. The variations in the inner 80% of the rings were found to be higher in smaller rings, implying that the larger rings had more areas of relatively uniform [CO2] to conduct experiments.

Case Studies on Food Production, Policy and Trade

The purpose of this book is to critically examine food security issues in Australia, a country that is often assumed to be food secure. Australia, although a substantial producer of agricultural products, currently has many citizens suffering food insecurity (Temple 2008) and a growing number with diet-related health problems (AIHW 2010). Governments see diet issues as important social and economic problems because: Many diet-related chronic diseases … are the major cause of death and disability among Australians. Poor nutrition is responsible for around 16% of the total burden of disease and is implicated in more than 56% of all deaths in Australia (NHMRC 2011a p7). In addition to health-related food insecurities, a range of other pressures impact increasingly on the cost of food as well as its production. For example, globalization exposes food supply systems in Australia to rising resource prices as world demand increases. Australia’s agricultural production is not immune to the negative aspects of climate change. Indeed Garnaut maintains that Australian agricultural and resource industries are likely to be affected profoundly by climate change and the global response to it (Garnaut 2010 p9). Economic and population growth, changing attitudes to biodiversity conservation, and the pressure of climate change on native biodiversity (Lindenmayer et al. 2010), also have implications for food security by increasing competition for resources, such as land and water (Alston and Whittenbury 2011; Carey et al. 2011). Consequently, the food production status of Australia will change and food security, including dietary issues, is likely to become increasingly important for Australians. In order to contextualize Australia’s food security challenges, and how a more sustainable, resilient and equitable food system might be created, we need an appreciation of global food security issues.

Spatial Variation of CO2 Inside Australian Grains Free Air Carbon Dioxide Enrichment (AGFACE) Rings

AGFACE facilities are being used to investigate the interactive effects of CO2, temperature, water supply and nitrogen on wheat growth, yield and quality. One of the engineering goals of AGFACE was to describe the extent of spatial variation of CO2 concentrations [CO2] inside AG-FACE rings and factors affecting it. Monitoring has shown that [CO2] is highly variable near the ring-edge where CO2 is emitted and declines non-linearly with the distance downwind of the ring-edge corroborating the findings of others. The spatial variation of [CO2] depends on ring size and the gap between ring and canopy heights but not wind speeds.