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This paper reports the first stage of a research project to investigate the vertical and horizontal spatial pattern of temperatures in the fires which are common throughout the dry deciduous dipterocarp forests of north and northeast Thailand from December to March every year. The work was carried out by using 'Thermocolor' mica pyrometers in experimental burns at three localities. The construction, calibration, field deployment and limitations of the pyrometers are fully described. It is shown that there are two basic types of vertical temperature profile, for which characteristic curves are provided. These occur in different forms in four main types of burn, namely: (1) typical litter burns; (2) extreme litter burns; (3) typical groundcover burns; (4) extreme groundcover burns. The fire characteristics of each are described in detail. Extreme groundcover burns may attain temperatures of between 700 and 900?C at 0.5-1 m above the ground and spread at rates exceeding 3.0 cm/s even in near windless conditions. Unfortunately, a policy of fire exclusion leads to the groundcover associations that give rise to this dangerous type of wildfire and a policy of prescribed burning is preferable. The insulating properties of both the sandy loam soils and the bark of savanna forest tree species are demonstrated and it is concluded that the dry deciduous dipterocarp forest ecosystem is well adapted to fire. Suggestions for further

The vegetation of the giant sequoia groves is dominated by Abies concolor, with Pinus lambertiana as a characteristic associate. Sequoiadendron giganteum is of small importance in relative density, but includes the majority of basal area of canopy species within the groves. Despite its great basal area, crown coverage of Sequoiadendron seldom exceeds 5%. Libocedrus decurrens is an important associate in lower-elevation groves, particularly following fire disturbance. Groundcover vegetation is extremely variable. Present grove boundaries appear to be remarkably stable. There is no evidence of any change in grove boundaries during the last 500 years or longer. A great majority of groves are undergoing a gradual decrease in density of giant sequoias due to low levels of regeneration. This decline in density began long before the influence of Western civilization on the groves.

Open-cut coal mining began in central Queensland’s Bowen Basin approximately 50 years ago. Over this period of time, mine rehabilitators have used a variety of tree, shrub, and groundcover species to create ‘novel ecosystems’ to stabilise soils and provide vegetative cover for pre-supposed final end-land uses. We examine post-mining rehabilitation from multiple soil and vegetation monitoring activities in the Bowen Basin to assess the similarity of landforms, plant composition, and trends in plant diversity compared to unmined reference communities. Rehabilitated spoil dumps and reference sites were assessed using soil and vegetation data contained in compliance monitoring reports from Goonyella Riverside, Moura, Oaky Creek, Rolleston, and Blackwater mines. Slopes, soil chemistry, and plant species mixes of rehabilitation aged from 2 to 22 years were compared to selected reference communities. Mines in this region have generally proposed one of two post-rehabilitation end-land uses: either pasture for cattle grazing or reconstructed native communities which potentially provide native fauna habitat. Landform data from a selection of these mine sites suggest that when their rehabilitation was compared to nearby reference sites median slope values were between 2.5 and 7 times steeper and soil pH, electrical conductivity, and phosphorus levels were significantly higher. The steeply sloped landforms, poor soil characteristics, depauperate native species pool, and uniform presence of exotic pasture grasses in the rehabilitation indicate that most of these newly created ecosystems should not be used for cattle grazing and also have few natural values. Legislative and community expectations have changed progressively over time and, although much of the rehabilitation is currently dominated by an assemblage of exotic buffel grass (Cenchrus ciliaris) and Acacia spp., recent environmental authorities suggest these ‘novel ecosystems’ will be judged against native reference sites. Upon completion of mining activities the resilience of these new ecosystems to drought, fire, and grazing will need to be demonstrated prior to lease relinquishment.