Search

The inspired sinewave technique (IST) is a non-invasive nonionising method which can measure accurately lung parameters. Six anaesthetised pigs were studied after surfactant depletion by saline-lavage. Paired measurements of lung heterogeneity were taken with the IST and computed tomography (CT). Lung heterogeneity measured by the IST was calculated by the ratio of tracer gas outputs measured at 180s and 60s. In CT images, lungs were manually segmented and divided into different regions according to voxel density. The IST and CT show strong agreement on lung heterogeneity measurements. In the IST ventilation heterogeneity value, the linear correlation in total of six pigs are weaker than individual animal (R2=0.33 vs R2=0.67 on average). The IST perfusion heterogeneity agreements are lower than IST ventilation values due to the IST technical setup. IST has the potential to measure the lung heterogeneity in ARDS animals.

Multi-temporal spatial datasets quantifying above ground biomass (AGB) are required for calculating national, regional and global carbon budgets, due to the large extent and rapidly changing nature of woodlands in Australia. This paper provides an overview of procedures for quantifying and scaling-up estimates of total AGB and component biomass from the tree to the landscape using remote sensing data and focusing on woodlands in Queensland.

The study assesses the consistency of relationships between the component (leaf, branch, and trunk) biomass of Australian woodlands and synthetic aperture radar (SAR) backscatter data acquired by airborne TOPSAR and spaceborne SIR-C SAR. The strongest relationships were observed between TOPSAR P-band data and all components of the biomass, with P-band I-IV considered most suited for quantifying total above ground biomass (TAGB) due to the larger dynamic range of the data and greater saturation level (80-100 Mg ha/sup -1/) in the relationship with TAGB. The main similarities observed between sensors were the strength of the relationships between C- and L- band data and component biomass, and the TAGB saturation levels of 20-30 Mg ha/sup -1/ and 50-60 Mg ha/sup -1/ for C- and L-band respectively.

The integration of JERS-1 SAR and Landsat TM data for quantifying and mapping carbon losses associated with vegetation clearance near Injune, central Queensland, Australia, is outlined. Above ground biomass (including stem and leaf components) was estimated for 70 plots by applying allometric equations to measurements of tree size taken in July, 1997. Significant Pearson's product moment correlation coefficients were derived between foliage biomass and Landsat TM NDVI and stem biomass and the JERS-1 SAR backscatter coefficient. To estimate above ground biomass, a simple regression model integrating both JERS-1 SAR backscatter and NDVI data was derived. For a property in central Queensland, spatial estimates of biomass were generated by applying the model to segmented JERS-1 SAR data. These estimates were combined with the Queensland Statewide Landcover And Trees Study (SLATS) land cover change data sets to estimate carbon losses associated with vegetation clearance between 1995 and 1997.