Jb Kirkpatrick

An iterative method for establishing priorities for the selection of nature reserves: An example from Tasmania

Abstract Past work ascribing priorities for the selection of nature reserves has weighted attributes and applied formulae in a single stage process. This single application of a formula means that areas of differing priority may contain similar mixes of species, communities or habitats, and may thus lead to imbalance in representation when preservation takes place, with some previously unpreserved or poorly preserved species, communities or habitats being found in several of the new reserves, and others being absent. An iterative method that has been applied to assess priorities for the preservation of threatened species in the central east coast of Tasmania overcomes this difficulty. The area with the highest score in the initial stages of analysis is assumed to be preserved and the weightings of attributes are altered accordingly. These new weightings are applied to locate the area of next highest priority, and the process continues until predetermined preservation goals are met.

The impact of fire on Tasmanian alpine vegetation and soils

Observations were made across 11-40-year-old fire boundaries in Tasmanian alpine areas of varying macroenvironment and flora. Organic matter and total nitrogen in the surface soil were significantly less where the vegetation had been recently burned. There were no significant differences between recently burned and recently unburned plots in contents of phosphorus, potassium, calcium or sodium or in pH. The burned plots contained few or no gymnosperms or deciduous shrubs, the most frequent dominants of the unburned vegetation. Most other shrubs were markedly less important in the burned than in the unburned plots, although most species of bolster form were little affected by fire, and some composite shrubs were most abundant on the burned plots. Most herbaceous species had equal or greater cover on the burned plots than on the unburned plots. The burned vegetation of the eastern mountains appeared to regenerate more quickly than that of the more oligotrophic western mountains.

Locating likely glacial forest refugia in Tasmania using palynological and ecological information to test alternative climatic models

Reservation planning should try to encompass those areas essential for biodiversity conservation in likely future climates, as well as the areas important today. Given that the glacial/interglacial cycles characteristic of the Quaternary are likely to continue, now widespread temperate forest types will be restricted to limited refugia in the future. Calibration of height of last glacial pollen records with contemporary vegetation types, and assumptions on the rate of spread of Nothofagus rainforest, are used to test the likelihood of a range of possible height of glacial climatic scenarios in Tasmania. These scenarios take into account changes in continentality and precipitation that seem likely to have occurred when Tasmania was a peninsula of Australia, rather than an island. The best-fitting scenario is consistent with a wide variety of evidence. It suggests that rainforest was highly restricted in height of glacial conditions, but alpine vegetation, eucalypt forest and woodland more widespread. Several apparent critical refugia for rainforest are identified.

Nature Conservation and the Regional Forest Agreement Process

The regional forest agreement process (RFA) arose from bitter, politically difficult, debates on the future of Australias forests. The approach to solving this debate that arose from the ecologically sustainable development and other processes was to take care of the reasonable conservation needs first, then facilitate economic development in the remaining forests. Unfortunately, the scientifically derived criteria for forest conservation developed by the Commonwealth were amended in the course of the RFA process such that the approach effectively became yet another compromise between conservation and development. To date, the public involvement in the development of regional compromises has been in the form of information and opinion input rather than decision-making, and the outcomes of both the East Gippsland and Tasmanian RFAs have not been accepted by conservationists as adequate. In the Tasmanian RFA in particular, there is a large distance between the outcomes and some of the indicative targets as...

The flammability and energy content of some important plant species and fuel components in the forests of southeastern Tasmania

Energy content and rate of flame front movement in various plant species and fuel components from the forests of southeastern Tasmania exhibited a range in values, and responses. Eucalypt dry forest species and fuel components showed the highest energy content and the greatest tendency to propagate fire whereas species from wet sclerophyll and gully habitats and Casuarina dry forest communities propagated fire less readily. Species from dry habitats have, in general, low ash contents, high energy levels, high volatile oil contents and low moisture contents. Wet habitat species have high percentages of moisture and ash. General support is given to the hypothesis that natural selection has favoured flammable characteristics in fire-dependent plant communities.

Variation in the Eucalyptus globulus Complex Revisited

Patterns of variation in the Eucalyptus globulus Labill. complex are reassessed by combining capsule measurements from an earlier study with recent collections, mainly of subspecies globulus. Four groups of populations are apparent and can be ascribed to the four subspecies maidenii, pseudoglobulus, bicostata and globulus. Intergrade populations between the latter three subspecies are widespread and mainly occur in the Otway Ranges and west Gippsland. There is a continuum in capsule morphology between the three-fruited subspecies, pseudoglobulus and bicostata. Subspecies globulus intergrades with these three-fruited intermediates. Three-fruited intergrade populations occuning north and south of the range of core pseudoglobulus can be differentiated and probably represent intergrades between pseudoglobulus and bicostata and between pseudoglobulus and globulus respectively. Reports of bicostata in the Furneaux Group and southern Victoria are thus probably erroneous and result from convergence in capsule morphology. The previously described taxon E. stjohnii (R. T. Bak.) R. T. Bak. is part of the continuum between subspecies pseudoglobulus and bicostata, but closer to pseudoglobulus. Populations phenotypically intermediate between and significantly different from globulus and the three-fruited intergrades are highly variable and occur in western Tasmania, on the northern end of Flinders Island, in the Otway Ranges and in west Gippsland. An isolated population on Rodondo Island is highly variable and has closest affinities to pseudoglobulus despite being within the geographical range of core globulus. The population from King Island is intermediate between the Otway phenotype and core globulus. The climatic regimes of the subspecies are markedly different and most three-fruited and globulus intergrade populations have closer climatic affinities to pseudoglobulus and globulus respectively. Hypotheses relating to the origin of the pattern of variation in E. globulus are discussed.

Vegetation-radiation relationships in mountainous terrain: eucalypt-dominated vegetation in the Risdon Hills, Tasmania

The vegetation along a north-south transect across a valley in the Risdon Hills, Tasmania, varies from Eucalyptus globulus-E, viminalis-E. amyg- dalina open-forest with a dense understorey of broad-leaved shrubs toE. Risdonii open-scrub with a sparse understorey of sclerophyll shrubs and graminoids. The variation in vegetation along the transect is highly correlated with total annual solar radiation, calculated to include the effects of shading, cloud cover and the sky view factor. The distributions of a large proportion of the species found along the transect are most highly significantly correlated with the solar radi- ation received in one of the solstice months. However, the response of most species to variation in incident solar radiation is curvilinear rather than linear. The topographically driest site does not possess the most xeric vegetation. This deflection is probably a consequence of downslope movement of soil moisture and runoff. Also, the most xeric vegetation tends to occur on northwest rather than north-facing slopes, possibly a result of an evapotranspiration peak in late

Phytogeographical analysis of Tasmanian alpine floras

List of vascular plant species were obtained from twenty-eight, disjunct, high altitude, treeless areas in Tasmania. These list pertained to vegetation dominated by the austral-montane element of the flora which is found both above and below the usually indistinct, and often absent, Tasmanian upper slope treeline. A polythetic, agglomerative classification of the Tasmanian and four Australian mainland alpine floras resulted in five groups: the mainland mountains, the eastern Tasmanian mountains, a group extending north-south through the centre of Tasmania, western Tasmanian quartzite mountains, and western Tasmanian mountains formed from more weatherable parent material. The Tasmanian floras form a continuum closely related to mean annual precipitation and surface geology, but not strongly related to continentality. Tasmanian endemism increases strongly from east to west, and similarity values with the mainland mountain floras and the New Zealand flora show the reverse pattern. It is suggested that the variation in and between the alpine floras of Tasmania and mainland Australia may be largely related to edaphic conditions

The environmental relationships of Californian coastal sage scrub and some of its component communities and species

Although the records of the earliest Spanish explorers in California largely avoid explicit mention of coastal sage scrub, they leave little doubt that the formation was present in areas where it exists today. The phenology and morphology of coastal sage scrub is such that it is better adapted than chaparral to occupy the drier parts of the Mediterranean climatic zone. Coastal sage scrub appears more successful than chaparral on argillaceous soils where sage usually occurs in mixture with Quercus agrifolia forest. Fire, while killing most coastal sage shrubs is followed by a rapid recovery of the formation through the agency of the widely dispersed subligneous shrubs, and other disturbances are often followed by a similar invasion. Most of the coastal sage associations and species show some strong correlation with one or several of altitude, a partial surrogate of continentality, aspect, slope or substratum. The major differentiation within coastal sage in the study area relates to continentality. However, the present patterns of distribution of coastal sage scrub and its component associations and species does not always correspond with neat environmental isolines, suggesting that past disturbance patterns have been perpetuated by homeostatic mechanisms.

Maintaining integrity compared with maintaining rare and threatened taxa in remnant bushland in subhumid Tasmania

The native vegetation remnants in the agricultural country of subhumid Tasmania are important strongholds for regionally and globally rare and threatened species. A detailed survey of the best 100 of these remnants indicated that there was no relationship between the size, age and juxtaposition of the remnants and an index of rare and threatened species, either in the data set as a whole or in phytosociologically defined subsets. Rare and threatened species were found in remnants of widely varying integrity, as indicated by native and exotic species richness and cover. Some species were only found in remnants that were of poor integrity. Efforts to preserve vegetation remnants need to be directed towards both those that are representative and of high integrity, and those that contain rare and threatened species. No great coincidence can be expected, because the causes of maintenance of good condition are not necessarily the causes of survival of many rare and threatened taxa.