Clive McAlpine

... McDonald, Geoff, Taylor, Bruce, Heyenga, Sonja, Smith, Tim, Pero, Lionel, Hoverman, Suzanne,McAlpine, Clive, Robinson, Cathy, Bellamy, Jennifer, Kearney, Fiachra, Smyth, Dermot, Whitehead, Peter, Metcalfe, Dan and Weston, Nigel (2006-06) Case studies in regional ...

Seabrook, L., McAlpine, C., Baxter, G., Bradley, A., Rhodes, J., Price, B. and Lunney, D (2008). The conservation of widely distributed species: Implications of the differences between western and eastern koala populations. In: , Proceedings of the Australian Rangelands Society 15th Biennial Conference. The Australian Rangelands Society, 15th Biennial Conference, Charters Towers, Australia, (). 28th September - 2nd October, 2008.

Climate change policies currently focus on reducing the concentration of industrial atmospheric greenhouse gases due to burning fossil fuels and deforestation, but pay limited attention to feedbacks between the land surface and the climate system. In tropical and subtropical regions, forests and woodlands play an important role in the climate system by buffering climate extremes, maintaining the hydrological cycle and sequestering carbon. Despite the obvious significance of these feedbacks to the functioning of the climate system, deforestation continues apace. It is critical, therefore, that a broader focus be developed that includes the restoration of feedbacks between vegetation and climate. In this paper, we present a synthesis of the best available, policy-relevant science on the feedbacks between the land surface and the climate system, with a focus on tropical and subtropical regions. On the basis of this science, we argue for a stronger integration of land-use and climate-change policies. These policies need to include a virtual halt to all deforestation and an acceleration of investment in strategic reforestation, supported by a comprehensive global forest monitoring program. Without these actions, the degradation of the Earth's ecosystems will become exacerbated as their resilience is eroded by accelerated changes in temperature, precipitation and extreme weather events.▶ Climate change policies currently focus on reducing the concentration of atmospheric greenhouse gases, but pay limited attention to biospheric forcings and feedbacks in the climate system. ▶ We urge a virtual halt to deforestation and accelerated investment in strategic reforestation, especially in tropical and subtropical regions, supported by a comprehensive global forest monitoring program. ▶ Without these actions, the degradation of the Earth's ecosystems will continue, exacerbated by, and exacerbating, changes in temperature, precipitation and extreme weather events.

The majority of landscapes around the world have been modified or transformed by human activities to meet the needs of human societies. The loss of native vegetation for agricultural development affects the sustainability of growing proportion of the world's ecosystems. Factors such as land tenure, roads and agricultural intensification, together with biophysical properties, have been cited as drivers of deforestation. This paper combined analysis of the historical drivers of change with analysis of the trends of deforestation since 1945 in two brigalow landscapes (100,000 ha) in sub-tropical Australia. A selection of these drivers were then applied at a property-level (1000 ha) to test their influence on native vegetation retention. Regression trees were used to identify significant human drivers and biophysical properties, and then a generalised linear modelling approach was used to quantify the effect of these factors on the proportion of remnant native vegetation. Results showed that until the mid-20th century, government policies to intensify settlement did not result in increased agricultural production, but since this time, landscape change has been rapid, and has particularly affected ecosystems on fertile clay soils. Although socio-economic factors were critical in driving deforestation, after 60 years of agricultural intensification by far the most significant explanatory variable determining the proportion of native vegetation retained at a property scale was the suitability of the soil for agriculture. Property size was an important secondary influence. The results were not, by and large, consistent with other studies of landscape change and suggest that generalised principles explaining deforestation may be elusive. Solutions to the problem of over-clearance of native vegetation, therefore, need to be tailored to the specific regional situations encountered.