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A Holocene palaeoenvironmental history from the World Heritage Area of southwest Tasmania is reconstructed using an 8000-year palynological record from Lake Fidler, a small meromictic lake adjacent to the lower reaches of the Gordon River. The sequence indicates that cool temperate rainforest has remained dominant in the region for at least the last 8000 years, confirming the wilderness value of this important conservation area. There is little evidence for fire in the region throughout this period and no discernible evidence for anthropogenic impact until approximately 1815 when small-scale convict logging activities commenced along the Gordon River. The record demonstrates the long-term presence of stands of one of the world's oldest living trees, Huon pine (Lagarostrobos franklinii), with significant increases in this species in the mid-to late Holocene. This expansion is evident in several Tasmanian records and is associated with declines in other important Tasmanian plant species. It is proposed that it represents a regional phenomenon possibly related to climate change. Examination of the climate signal from other Australian Holocene pollen records provides some support for this interpretation.

The Savage River iron ore mine in north-west Tasmania, Australia, is surrounded by areas of high wilderness value, including the Savage River National Park. Acid rock drainage (ARD) emanating from legacy (sulphide containing) waste rock dumps at the mine site, which flows into both Main Creek and Savage River, has caused environmental harm to the river and its tributaries. The historic B-dump was identified as a significant source of ARD at the site. In 2006, combined water shedding and alkaline (calcite-chlorite schist) covers were constructed over the dump for long-term ARD control. As part of the AMIRA International funded project "Alternative Treatment Options for Long-term ARD Control" (P933A) a survey of the B-dump calcite-chlorite schist (CCS) side cover was carried out. Combined excavation and drill core sampling of the dump and CCS side cover was undertaken after the cover had been in place for about five years. This paper focuses on the results from our investigations of water samples taken from B-dump seeps and solid samples, in particular, drill core samples taken from different layers of the cover and original ARD rock within the dump. A mineralogical survey, geochemical characterisation and surface analysis of pyrite in each of the layers were undertaken.

The section on preparing a plan for access and recreation should be regarded as an integral component of a full management plan and not as an independent document. There may be occasions when there is a need to present the section as a stand-alone document, but its relationship with the remainder of the site plan must not be forgotten. One of the key components of the access section is the identification of the carrying capacity of the site. This is the level of access that can be accommodated without detracting from the quality of the experience that visitors enjoy on the site. There will be two main areas of impact: Visitors can have a direct impact on the infrastructure, landscape and wilderness qualities of a site, for example, paths may become over-wide and unsightly. People can also visit sites in such large numbers that they become a distraction to others. This is particularly important in areas of high landscape or wilderness value. An access objective with performance indicators is required for most sites. Performance indicators for access must be measurable and quantified (i.e. so that they can be monitored), and the data should be easy to collect. The number of indicators should be kept to a minimum, but there should be sufficient to provide the evidence necessary to ensure that the quality of the access provisions can be measured.

We examined the geology of a small inland wetland in Hampton, Connecticut to determine its postglacial history and to assess the severity of human impact at this remote wooded site. Using stratigraphic evidence, we dernonstrate that the present wetland was created when sediment pollution from a 19th-century railroad filled a preexisting artificial reservoir, and that the prehistoric wetland was a narrow drainage swale along Hampton Brook. This same, severely impacted wetland was interpreted by the Pulitzer Prize-winning naturalist Edwin Way Teale as a beautiful wilderness area of particular interest. These conflicting perceptions indicate that artificial wetlands can be naturally mitigated in less than a century of healing, even in the absence of deliberate management. We also point out that the “wilderness” value of the Teale wetland was in the eye of the beholder and that unseen human impacts may have improved the aesthetic experience.

This research advances the understanding of the location of perceived landscape values through a statistically based approach to spatial analysis of value densities. Survey data were obtained from a sample of people living in and using the Murray River region, Australia, where declining environmental quality prompted a reevaluation of its conservation status. When densities of 12 perceived landscape values were mapped using geographic information systems (GIS), valued places clustered along the entire river bank and in associated National/State Parks and reserves. While simple density mapping revealed high value densities in various locations, it did not indicate what density of a landscape value could be regarded as a statistically significant hotspot or distinguish whether overlapping areas of high density for different values indicate identical or adjacent locations. A spatial statistic Getis–Ord Gi* was used to indicate statistically significant spatial clusters of high value densities or “hotspots”. Of 251 hotspots, 40% were for single non-use values, primarily spiritual, therapeutic or intrinsic. Four hotspots had 11 landscape values. Two, lacking economic value, were located in ecologically important river red gum forests and two, lacking wilderness value, were near the major towns of Echuca-Moama and Albury-Wodonga. Hotspots for eight values showed statistically significant associations with another value. There were high associations between learning and heritage values while economic and biological diversity values showed moderate associations with several other direct and indirect use values. This approach may improve confidence in the interpretation of spatial analysis of landscape values by enhancing understanding of value relationships.

The hydroelectric developments portended in South-West Tasmania would inundate tracts having major wilderness and archaeological values as well as threaten a much larger area of wilderness. The development of the region is ‘justified’ by the construction authority, in terms of an expected high rate of electricity demand towards the year 2000. However, a range of independent demand analyses suggest that the demand for electricity in Tasmania will not approach the Hydro-Electric Commission's expectations. Thus a lag in demand may be identified which should provide time for a rigorous evaluation of the wilderness value of the region together with an appraisal of the alternative electricity-generation options.Currently, it appears that a cost advantage exists for the favoured ‘Gordon-below-Franklin’ project. However, the opportunity-cost differential of this project relative to several less-damaging alternatives is slight, at least when the growth in wilderness and electricity demands are considered. The opportunity-cost tradeoff appears quite trivial when current tourist and recreational impacts are accounted for.

Structural analysis of the subalpine forest in southern Alberta shows that the old—growth Picea—Abies forest has succeeded even—aged stands of Pinus contorta var. latifolia Engelm. that became established after fire 150—200 or more years ago. Because P. Contorta regeneration fails beneath its own canopy, an irregular— to uneven—aged understory of Picea engelmannii Parry x P. glaca (Moench) Voss. and Abies lasiocarpa (Hook) Nutt. becomes established. As the even—aged P. contorta overstory ages, sporadic death of overmature trees permits an irregular— to all—aged Picea—Abies forest to emerge and dominate, unless fire reinitiates the succession to even—aged P. contorta. Extensive and frequent fires in the past, mainly initiated by "dry" electrical storms, have prevented long—term successional development and have maintained most of the forest in the early P. contorta—dominated phase of the succession. Introduction of effective fire protection is now permitting progress toward the late successional phases. Widespread development of the Picea—Abies phase and the decadent Abies—Picea phase that follows are forecast. The ecological effects of such fire—protection policies are questioned. A silvicultural program of fire prescription is suggested for the maintenance of the fauna and wilderness value of the mountain national parks. Silvicultural alternatives in harmony with the ecology of the forest are suggested for the implementation of multiple—use policies in the Rocky Mountain Reserve.