Initial Effects of Deforestation on Herbaceous Species Composition in Grassy Woodlands of the Northern Tablelands, NSW Australia

Limited information on the initial effects of clearing and thinning on herbaceous vegetation of grassy temperate eucalyptus forests exists. The aim of this investigation is to study the initial changes in species composition following clearing and thinning. A deforestation experiment was established where clearing, thinning of 50% of canopy cover and control treatments were established. In the open-forests, patterns in herbaceous species composition were strongly influenced by the presence of trees, with weeping wheat grass (Microlaena stipoides) dominant, whereas wiregrass (Aristida ramosa) dominated interspaces and canopy gaps. Immediately following clearing, significant changes in the herbaceous species composition were observed, with 26 new species recorded. The original vegetation pattern was lost, being replaced by Cyperaceae and Juncaceae, and a large number of invasive ruderal species. A state and transition model that describes the changes in composition is presented

Development of a Grazing Land Management Education Program for Northern Australia’s Grasslands and Grassy Woodlands

Recognition of the potential to enhance grazing land management to meet the goal of sustainable beef production has been increasing over the past decade. Recognition of the relationship between poor land management and negative off-site environmental impacts, such as soil erosion and a decline in the condition of rivers and adjacent near shore coastal areas from sediment transport, has increased also. This concern has matured somewhat to include the critical link between land condition and production, and the threat to sustainable carrying capacity that comes from declining land condition. Concurrently, interest has increased in optimising the use of pasture, e.g. through the development of infrastructure (watering points, fencing), through more pro-active management e.g. alternative grazing systems, spelling of pastures, and through pasture development. In fact, it can be argued that achieving production goals while improving and maintaining the health of the land has become the major on-property issue for northern Australian graziers

Assessing the value of trees in sustainable grazing systems

The retention of trees in strips provides an option for managing non-remnant woody vegetation in native and sown pastures in northern Australia. However, the impact of tree strips on pasture production has not been previously researched in detail in southern Queensland. The influence of existing tree strips on pasture production in southern Queensland was measured at three grazing properties during 2004 and 2005. Soil and pasture attributes were sampled along transects 80 to 300 metres in length positioned perpendicular to tree strips. The tree strips ranged from 15 to 75 metres wide and were 120 to 500 metres apart. The effects of tree strips along the pasture transect were quantified in terms of pasture microclimate (e.g. temperature, humidity and, at one location, wind), pasture growth in grazed and exclosed situations, soil water, soil nutrients and condition, and nutrient availability. An experimental approach using exclosed pasture transects provided a useful ‘bioassay’ potentially integrating beneficial and competitive effects of tree strips on pasture growth as well as other factors (e.g. soil variability). Averaged across two locations and two years, the competitive effects of the tree strip were compensated to some extent by enhanced pasture growth at distances of 1-6 x tree height from the tree strip edge. However, the observed effects on pasture growth along the transect were likely to be due to different causes: pasture microclimate at one site, soil texture and microtopography at a second site and pasture establishment history at a third site. Thus, the trial highlighted the difficulty of attributing effects in real-world situations, given the number of possible causes including the tree strip effects on pasture microclimate and nutrient availability, soil surface disturbance, and systematic variation on soil and water redistribution due to soil micro-topography and felled timber. Despite these many sources of variation, general effects were derived from the field data consistent with other studies on tree strips and wind breaks across Australia. To extrapolate the project results to other locations, tree strip configurations and climates, a new version of the soil waterpasture growth simulation model GRASP was developed allowing simulation of tree and pasture effects and processes for various distances along a pasture transect perpendicular from the tree strip

Carbon capture project, final report. An evaluation of the opportunity and risks of carbon offset based enterprises in the Kimberley-Pilbara region of Western Australia

Commercialisation of carbon in the Australian Rangelands could lead to the development of a multi-billion dollar industry, and Western Australia has the potential to capture a significant share of this revenue. A significant proportion of the WA Rangelands is degraded which is the legacy of the exploitative practices of historical pastoral development and the mining industry. Full environmental restoration of these areas is well beyond the fiscal capacity of land managers and the WA State Government. Carbon based enterprises have the potential to restore large tracts of degraded land in a cost-effective manner and can deliver a number of other socio-economic co-benefits to regional WA. The WA Rangelands have the potential to play an important role in mitigating the adverse impacts of climate change primarily through biosequestration and controlled savanna burning programs. There are a number of issues which need to be resolved in order for this potential to be realised. This study makes a contribution to the resolution of some of these issues. The principal findings from this study include: 1. GHG emissions produced by the three case study businesses ranged from 0.02 to 2 t CO2-e ha-1 yr-1 or 2.2 to 10.9 t CO2-e per cattle unit yr-1 (inclusive of emissions from livestock methane, diesel and petrol consumption and savanna burning). 2. Livestock methane and savanna burning constituted the majority of the GHG emissions that were produced by the case study pastoral businesses (\u3e 90% of the total). 3. The estimated baseline amount of total carbon of the 12 land-systems surveyed in this study ranged from 100 to 373.7 t CO2-e ha-1 (inclusive of carbon stored in the woody vegetation, coarse woody debris, herbaceous standing and surface litter and the soil pools).https://library.dpird.wa.gov.au/bulletins/1220/thumbnail.jp

Carbon capture project, final report. An evaluation of the opportunity and risks of carbon offset based enterprises in the Kimberley-Pilbara region of Western Australia

Commercialisation of carbon in the Australian Rangelands could lead to the development of a multi-billion dollar industry, and Western Australia has the potential to capture a significant share of this revenue. A significant proportion of the WA Rangelands is degraded which is the legacy of the exploitative practices of historical pastoral development and the mining industry. Full environmental restoration of these areas is well beyond the fiscal capacity of land managers and the WA State Government. Carbon based enterprises have the potential to restore large tracts of degraded land in a cost-effective manner and can deliver a number of other socio-economic co-benefits to regional WA. The WA Rangelands have the potential to play an important role in mitigating the adverse impacts of climate change primarily through biosequestration and controlled savanna burning programs. There are a number of issues which need to be resolved in order for this potential to be realised. This study makes a contribution to the resolution of some of these issues. The principal findings from this study include: 1. GHG emissions produced by the three case study businesses ranged from 0.02 to 2 t CO2-e ha-1 yr-1 or 2.2 to 10.9 t CO2-e per cattle unit yr-1 (inclusive of emissions from livestock methane, diesel and petrol consumption and savanna burning). 2. Livestock methane and savanna burning constituted the majority of the GHG emissions that were produced by the case study pastoral businesses (\u3e 90% of the total). 3. The estimated baseline amount of total carbon of the 12 land-systems surveyed in this study ranged from 100 to 373.7 t CO2-e ha-1 (inclusive of carbon stored in the woody vegetation, coarse woody debris, herbaceous standing and surface litter and the soil pools).https://researchlibrary.agric.wa.gov.au/bulletins/1220/thumbnail.jp

Safety Assessment of the Oral Cavity Probiotic Streptococcus salivarius K12

Streptococcus salivarius is a prominent member of the oral microbiota and has excellent potential for use as a probiotic targeting the oral cavity. In this report we document safety data relating to S. salivarius K12, including assessment of its antibiogram, metabolic profiles, and virulence determinants, and we examine the microbial composition of saliva following the dosing of subjects with K12

Climate change impacts on biodiversity in Australia : outcomes of a workshop sponsored by the Biological Diversity Advisory Committee, 1-2 October 2002

98 page(s

Indicators of Climate Change

5 page(s