The Holocene climatic history of tropical northern Australia is re-examined using the recently published pollen record from Groote Eylandt to corroborate and refine previous climatic inter pretations. We identify a four-stage Holocene comprising: (1) a continuous increase in effective precipitation (EP) from the beginning of the Holocene to about 5000 BP; (2) a mid-Holocene EP maximum from about 5000 to about 4000 BP; (3) a marked decline in EP somewhere between 4000-3500 Bp; and (4) an EP recovery in the last <2000 years. The mid-Holocene EP maximum is 1000 years later than Holocene EP maxima from temperate Southern Australia and suggests that the records are decoupled at this time. We focus on pollen evidence of environmental change at c. 4000 BP, which marks a break between a continuously ameliorating (increasing EP) climate but with small mean variation in the earlier Holocene and a steady (no directional trend) but highly variable later Holocene. We believe that this break represents the first evidence from the monsoonal lowlands of northern Australia for the onset of 'modern' ENSO-dominated ocean-atmosphere interactions in the Holocene. A simple conceptual model of trans-Pacific teleconnections is presented to explain this onset and as an hypothesis for testing.
Defines the concept of corporate culture and shows how it affects organizations (both positively and negatively). Corporations that have been successful in establishing and fostering positive cultures are profiled. The authors find that an effective culture must be aligned with employee values and be consistent with the environment in which the organization operates. While it is best to establish a positive culture with which employees can identify during an organization's infancy, it is possible to change an existing culture. Such change is best accomplished by modeling desired behavior at all levels of management and by planning events that foster frequent interaction among cross-functional employees. Concludes that a positive culture can provide a significant competitive advantage. T h e rese a rch reg is te r fo r th is jo u rn a l is a v a ila b le a t http://www.m cbup.com/research_registers T h e cu rren t iss u e a n d fu ll tex t a rch iv e o f th is jo u rn a l is a v a ila b le a t http://www.emerald-library.com/ft
I LEES, B,.2OO6. Timing and formation of coastal dunes in northem and eastern Australia. Journa/o/"Coas/a/iiesearc/i 22(1), 78-89. West Palm Beacb (Florida), ISSN 0749-0208.This article revisits the debate about the processes of coastal dune initiation in Australia. A review of the dates puhhshed so far on coastal dunes in Australia indicates that these belong to identifiable process regions. Those to the north and northeast seem to be largely derived from the deflation, at low sea levels, of exposed deltaic sediments, which are subsequently reworked by episodes of active transgressive dune development. In the southeast, the dunes, hke other coastal depositional features, are largely derived from the alongshore sediment transport system, which is active along this coast at times of higher sea level. Apart from during glacial maxima, episodes of dune transgression, where a source is identifiable, seem to be initiated along the shoreline, strongly suggesting that marine disturbance is the trigger. Although, in many cases, these are also at times when climate is favourable to active transgressive dune development, the eastern Cape York dune fields make it clear that this is not a necessary condition.
/ Decision tree analysis was used to predict the distribution of forest communities in an area on the south coast of New South Wales. Australia, The analysis was carried out using a geographical information system environmental data base of those topographic and geological variables thought to influence the distribution of vegetation and derived from cartographic sources. The resulting maps of forest communities are of a resolution sufficient to delimit individual forest stands and contain much ecological information.A major priority of environmental ntanagement in Australia is the developntent of cost-effective methods for mapping native forests. The aim is to produce maps of these forests that provide information not only about the location and extent of timber resources, but also ecological information to assist forest HI~:lltagers in developing and implententing muhiuse management policies. For forest managentent purposes, vegetation maps should be of sufficient resolution to delimit forest stands, which are contiguous regions occupied by a single community. Such maps would show the extent of forest communities within ntanagement compartments. Survey of forest communities at such fine resolutions is a labor-intensive and costly exercise because of the size and highly variable nature of many of the forests.Most vegetation surveys in these torests employ some combination of field work and phutointerpretation, sometimes in conjunction with satellite image analysis. These are not alternative ntapping ntethods. Manual survey can be assisted greatly by photointerpretation, and the production of reliable vegetation maps from aerial photographs or satellite data requires a significant investment of field work for interpretation and verification (Zonneveld 1988). htitially it appeared that multispectral satellite dam could be digitally analyzed to produce vegetation maps with little investment of labor. Such dam would appear to have great potential as a cheap, readily updaud)le
/ The integration of Landsat TM and environmental GIS data sets using artificial intelligence rule-induction and decision-tree analysis is shown to facilitate the production of vegetation maps with both floristic and structural infermation. This technique is particularly suited to vegetation mapping in disturbed or hilly environments that are unsuited to either conventional remote sensing methods or GIS modeling using environmental data bases.Current concerns worldwide with the management of native forests have led to a renewed interest in the development of rapid, cost-effective methods ibr forest mapping. Before any assessment can be made of the nature of vegetation in a given area, it is necessary to know what species are predominant, how they are distributed, and their relative abundance. Basic to the description of vegetation is a knowledge of floristics, lifeform, and structure. Traditional methods of mapping these attributes using a combination of field survey and photointerpretation are both labor-intensive and slow. Hopes that digital remote sensing would reduce time and costs, yet routinely produce acceptable thematic maps of vegetation and forest type, have not yet been met. In southeast Australia, where this study was carried out, remote sensing can often successfully distinguish structural communities (Walker and others 1986, Jupp and others 1986). The identification of floristic associations and life-forms is much less successful using only remote sensing. Although the difference between the reflectance of eucalypt leaves, in particular, appears to offer promise that some species discrimination is possible using remote sensing (Figure 1), leaf reflectance varies greatly within a single tree where there are mature and juvenile leaves present along with old, insectdamaged ones. Laboratory measurements show that the spectral variability of leaves within a eucalypt species
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