Matthew Brookhouse

Eucalypt dendrochronology: past, present and potential

Dendrochronology has the capacity to provide unique insights into natural vegetation dynamics and yield climatological reconstructions. However, because of a persistent belief that eucalypts are unsuited to dendrochronological analysis, research interest in the genus has been limited. A thorough review of the eucalypt dendrochronological literature reveals that perceived limitations may be locally overcome. However, methodological problems associated with many studies mean that results are often difficult to interpret. Consequently, the dendrochronological potential of the eucalypts remains unresolved. To overcome this, a detailed dendrochronological reconnaissance of the eucalypts, drawing on established datasets, systematic study of individual species and sites and examination of non-width-based tree-ring properties, is recommended.

Green Carbon Part 2. : The role of natural forests in carbon storage

This report is the second in a series that examines the role of natural forests and woodlands in the storage of carbon. Understanding the role of natural ecosystems in carbon storage is an important part of solving the climate change problem. This report presents a landscape-wide green carbon account of the ‘Great Western Woodlands’ (GWW), sixteen million hectares of mostly contiguous natural woody vegetation to the east of the wheatbelt in south-western Western Australia. For the first time, we provide an overview of the vegetation structure, climate, geology and historical land use of the GWW, and examine how these interact to affect the carbon dynamics of this region’s landscape ecosystems. An analysis of time-series of satellite imagery is used to develop a fire history of the GWW since the 1970s. These layers of environmental information, along with field survey data and remotely sensed greenness, are used to construct a spatial model to estimate biomass carbon stocks of the woodlands at the present day, and to infer an upper limit to the carbon sequestration potential of the GWW. A range of management options to enable protection of high quality carbon stocks and restoration of degraded stocks are evaluated.

Application of the Minimum Blue-Intensity Technique To A Southern-Hemisphere Conifer

ABSTRACT Minimum blue-intensity (BI) appears to be a viable source of proxy-temperature data, but is yet to be applied to a Southern-Hemisphere species. Here, we apply the BI technique to Podocarpus lawrencei, a conifer endemic to the Australian Alps. We develop sample-preparation protocols and examine the climate sensitivity of resulting tree-ring width (TRW) and BI chronologies. We found that extractable resins were removed from P. lawrencei samples after 28 hours of Soxhlet extraction and a highly-significant negative correlation (r = -0.79, p<0.0001) exists between the resulting BI chronology and growing season (August–April) temperature maxima. The climate sensitivity of our BI data, combined with an apparent teleconnection with a previously-reported dataset, suggests that an unparalleled opportunity exists to develop a powerful proxy for growing-season temperatures in southeast Australia.