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Alpine snowpatches are characterised by persistent snow cover, short growing seasons and periglacial processes, which has resulted in highly specialised plant communities. Hence, these snowpatch communities are among the most threatened from climate change. However, temporal dynamics in snowpatch microclimate and plant composition are rarely explored, especially in the marginal alpine environments of Australia. Seven snowpatches were categorised into early, mid and late snowmelt zones based on growing season length, with soil temperatures recorded from 2003 to 2020 and plant composition surveyed in 84 1 m² quadrats in 2007, 2013 and 2020. Microclimate, species diversity, plant cover and composition, along with community trait-weighted means and plant strategies were assessed to understand snowpatch dynamics in response to climate change. We found that growing season length and temperatures have increased in late melt zones, while changes were less consistent in early and mid melt zones. There were few changes in species diversity, but increases in graminoids and declines in snowpatch specialists in mid and late melt zones. Community-weighted plant height, leaf area and leaf weight also increased, particularly in mid and late melt zones, while plant strategies shifted from compositions of ruderal-tolerant to stress-tolerant. Here, we show that snowpatch communities are rapidly changing in response to longer growing seasons and warmer temperatures, with the greatest changes occurring where snow persists the longest. The results highlight the climate-induced loss of defining biotic and abiotic characteristics of snowpatches, as temporal convergence of compositions along snowmelt gradients threatens the novelty of snowpatch plant communities.

High mountain environments are often characterised by low temperatures and short growing seasons, yet support high plant endemism and biodiversity. While such ecosystems are considered among the most vulnerable to climatic warming, the impacts of climate change on diversity and composition can be complex. To develop a deeper understanding of these dynamics, changes in vegetation over time along five alpine summits that are part of the Global Observation Research Initiative in Alpine Environment (GLORIA), were assessed including species richness, α-diversity, β-diversity, vegetation and growth form cover as well as composition. The five summits of Mount Clarke in the Australian Alps were surveyed in 2004, 2011 and 2019. Despite increases in species richness over time, there was an overall decline in diversity through biotic homogenisation across the summits. Near complete vegetation cover was recorded in 2004 but increased over the 15 years via in-filling and densification, driven by increasing cover of graminoids and shrubs. Consequently, there was also a shift in species composition which was greatest at higher elevations. The results indicate that there has been a shift towards more competitive and thermophilic composition, which may have implications for flammability in a warming and drying climate. Further assessments will be required to more fully explore the effect of climate variation from climate change, and implications for conservation of this and other alpine floras globally.

Over winter, alpine plants are protected from low-temperature extremes by a blanket of snow. Climate change predictions indicate an overall reduction in snowpack and an earlier thaw; a situation which could expose the tips of shrubs which extend above the snowpack to freezing events in early spring, and cause foliar frost damage during the onset of physiological activity. We assessed the photosynthetic responses of freezing-damaged shrub leaves from an assay of freezing temperatures in the Snowy Mountains in south-eastern Australia, using chlorophyll fluorometery ex situ. We sampled leaves that were exposed early during the spring thaw and leaves that were buried in snow for up to two extra weeks, from four evergreen shrub species at monthly intervals following the period of snowmelt. Freezing resistance (estimated from LT50) was poorest at the earliest spring sampling time, in both exposed above-snow and protected below-snow foliage in all species. Protected foliage in early spring had lower freezing resistance than exposed foliage, but not significantly so. By the third sampling time, freezing resistance was significantly better in the lower protected foliage (LT50 of − 14) compared with the upper exposed foliage (LT50 of − 10) in one species. Over the course of spring, freezing resistance improved significantly in all species, with LT50 values of between − 10 and − 15 °C by the third sampling time, which is lower than the minimum air temperatures recorded at that time (> − 5 °C). The results indicate that the dominant evergreen shrub species in this area may only be susceptible to freezing events very early in spring, before a period of frost-hardening occurs after snowmelt. Later in spring, these alpine shrubs appear frost hardy, thus further perpetuating the positive feedbacks surrounding shrub expansion in alpine areas.

Alpine snowpatches are areas that, due to topographical and climatic factors, retain snow long after the thaw in the surrounding landscape. Within snowpatches there are often reliable patterns of snowmelt resulting in differences in plant composition, with snowpatch specialists limited to areas of late snowmelt. In 2013, we resurveyed vegetation in early, mid and late snowmelt zones across seven alpine snowpatches in the Snowy Mountains, Australia, 6 years after the initial 2007 survey. In both surveys, there were differences in vegetation cover and species composition among snowmelt zones; in particular, the cover of graminoids was higher in areas of earlier thaw. Differences in functional composition between survey periods were determined using functional traits (plant height, percent leaf dry matter content and specific leaf area) to calculate community trait-weighted means. In both surveys, early and mid snowmelt zones were dominated by taller species with larger leaves, mostly graminoids. Notably, by 2013 there was an increase in species richness in the late snowmelt zone and an increase in the cover of the tall tussock grass Poa costiniana across all snowmelt zones, driving changes in the community trait-weighted means for plant height and specific leaf area in the late snowmelt zone. The results highlight that snowpatch vegetation can change within relatively short time periods and that snowpatch plant communities may not remain as discrete units in the near future due to the encroachment of more competitive and productive species from the surrounding landscape.

Subalpine ecosystems are centres of endemism that are important for biodiversity. However, these areas are under threat from the creation, expansion and continued modification of ski runs, activities that have largely negative effects on wildlife. Despite this threat, research on the impacts of ski runs is limited for reptiles—particularly regarding the value of remnant vegetation retained on ski runs. Here we quantify the effects of habitat loss and fragmentation (i.e., patch size, patch isolation and edge effects) on the abundance of a common subalpine lizard and on thermal regimes (a key determinant of lizard distribution) in an Australian ski resort. The number of lizards observed differed significantly with habitat type (ski runs vs. forested areas) and patch isolation, but not patch size. In addition, the edges of patches supported more lizards than any other habitat type. These patterns of lizard distribution can be explained, in part, by the differing thermal regimes in each habitat. Ski runs had significantly higher ground surface temperatures than any other habitat type, precluding their use for a considerable proportion of the activity period of a lizard. In comparison, edges were characterised by lower temperatures than ski runs, but higher temperatures than the core of forested areas, potentially providing a favourable environment for thermoregulation. Based on our results, we conclude that although modified ski runs have a negative effect on lizards, patches of remnant vegetation retained on ski runs are of value for reptiles and their conservation could help mitigate the negative effects of habitat loss caused by ski run creation.

European hares (Lepus europaeus) are grazers and open grassland specialists that are replaced in mountain areas of their natural range in the northern hemisphere by browsing/intermediate feeding mountain hares (Lepus timidus), but in their introduced range in the southern hemisphere, occupy the alpine zone. We used micro-histological identification of plant fragments and germination of seeds in faecal pellets of L. europaeus from the Snowy Mountains, Australia, to determine diet. We asked whether diet shifted and/or diet breadth expanded in response to seasonally reduced food availability, particularly during winter. If so, did the constraints of food availability in the alpine zone lead to the diet mirroring that of L. timidus in its native alpine habitat. The diet of L. europaeus was dominated by grasses, herbs and shrubs. The main diet items in summer were grasses (70 %) and herbs (28 %). Grasses declined in the diet between summer and autumn when herbs increased to co-dominance, with a further change after establishment of the winter snowpack to a greater preponderance of shrubs (43 % compared with a maximum of 3 % in snow-free months). L. europaeus selected a wider range of plants in winter (59 species compared with 39 in summer) and diet was significantly more variable in winter than in autumn or summer (and in autumn than summer). We concluded that the persistence of L. europaeus in alpine areas of the southern hemisphere is testament to their ability to expand their dietary breadth to occupy mountain climatic zones normally occupied by L. timidus.

In response to climate warming, high altitude alpine vegetation may be replaced by typically lower altitude species, as species re-assemble and migrate to new areas. However, empirical evidence showing vegetation change in response to climate warming is largely unavailable for Australian alpine areas. Here, we examine changes in species richness with respect to climate and altitude over a 7 year period at a range of spatial scales in a re-survey of five alpine summits that are part of the Global Observation Research Initiative in Alpine Environments monitoring network. Eighty species were recorded in 2011 across all summits, an increase of 6 species since 2004. Mean species richness increased at the whole-of-summit scale from 45 to 50 species (about 12 %). At this scale, the rate of species richness increase was almost one new species per year, with 15 new species recorded at one summit. Here, shrub and graminoid species showed the largest increases. At the smaller spatial scales, changes in species richness were less pronounced. Turnover at the species and community level was typically moderate at all spatial scales and on all summits. The strength and direction of species richness change (the difference in species richness between the two sample periods, +/−) was not related to altitude nor variation in climate. Future re-surveys of the summits will confirm whether these short-term variations in species richness, particularly increases in shrubs, are indeed signals of longer-term trends and interactions with a changing climate.

Environmental filters act to limit the local community assemblage from the regional species pool by restricting the viable trait states that can occur there. In alpine snowpatches, the timing of snowmelt is a strong environmental filter. In coming decades, the strength of this filter is likely to relax with global climate change. We used three continuous plant functional traits (leaf area, plant height, seed mass) and their divergence (using the FDvar index) to document current patterns of community assembly and predict plant community responses to future environmental filters in alpine snowpatch vegetation. The community trait-weighted mean for leaf area and height, but not seed mass, was significantly higher in early snowmelt zones relative to mid and late melting zones across all snowpatches. Mean FDvar for height (but not leaf area or seed mass), by contrast, was substantially lower in early snowmelt zones, indicating that species growing in early melt zones are consistently taller than those growing in other zones. These results suggest that if climate change leads to earlier snowmelt and hence, a longer growing season, taller (more competitive) species with larger leaf areas (more productive) may replace short species in snowpatches as these plant communities re-assemble in response to changing environmental filters.

The phenologies of plants and animals in snow-covered landscapes are expected to accelerate with global warming. However, there are few studies that have examined a range of unrelated taxa in alpine environments to determine whether there is commonality in the proximate causes, synchrony in timing, or the direction of any changes. Records for five alpine animal species and two alpine plant species, chosen primarily for their visibility, were examined to determine their temporal response to regional climate warming. Over the 30-year period studied, they showed an array of different phenological responses. Plant flowering appeared linked to date of snow melt, whereas animal responses varied. Although having accelerated phenologies, two migratory bird species exhibited contrary changes; one to low-altitude warming regardless of snow conditions in the alpine zone (flame robin) and the other to state of the snowpack regardless of low-altitude temperatures (Richard's pipit). By contrast, the migratory bogong moth arrived significantly later over the years with no apparent explanatory climatic cause. Although bogong moths are not responding to earlier snow melt, insectivorous predators on the ground are. This could lead to a serious mismatch in timing at different trophic levels, putting pressure on endangered vertebrates. Emergence of locally wintering insect species, March flies and Macleay's swallowtails, were not significantly related to measured climatic parameters over the study period. A consequence of the disparate responses to climate warming recorded here is the questionable value of 'indicator species' to examine the impact of climate warming on alpine ecosystems.

This study examines vascular plant species richness along an altitudinal gradient in alpine Australia. Vascular plant composition and soil temperature records were obtained for five summits (from 1729 m to 2114 m a.s.l.) using sampling protocols from the Global Observation Research Initiative in Alpine Environments program. Species richness was examined against altitude, aspect and climatic variables at different spatial scales (10 × 10 cm quadrats, 1 m2 quadrats, clusters of 4 * 1 m2 quadrats, for the summit area above a line 5 m altitudinally below the summit (the −5 m isoline), for the extended summit down to the −10 m isoline). About 75 taxa (70 species, 5 graminoid genera) were recorded, 9 of which are endemic to the small alpine area of ∼100 km2. There were significant linear relationships between species richness and altitude and climatic variables for the top to −5 isolines on the summits. However, there was no consistent pattern for species richness at other spatial scales, altitude, aspect or climatic variables. The proportion of species for the whole summits with localised distributions (local endemics) increased with altitude. Predicted increasing temperatures and reduced snowcover is likely to result in an increase in species richness as shrubs, herbs and introduced weeds become more common at higher altitude. Because Australian alpine areas occur in narrow altitudinal bands with no nival zone, there are no higher altitudinal refuges available for alpine species. Therefore many of these species are likely to be at risk of extinction from climate change.

The study of winter-active small mammals beneath the snowpack has proved challenging for researchers because of the relative inaccessibility. We present a technique using hair tubes that permits the detection of small mammals active in the subnivean space. Hair tubes are cylindrical or funnel-shaped structures containing suitable bait and an adhesive surface that harvests hairs from small mammals as they attempt to reach the bait. Hair tubes eliminate many of the difficulties often associated with live trapping and permit the expansion of systematic sampling to larger scales than allowed by conventional live-trapping methods. The technique was used successfully to detect five small mammal species in the subnivean space in Kosciuszko National Park (KNP) in southeastern Australia. These included the common bush-rat, Rattus fuscipes; the dusky and agile antechinus, Antechinus swainsonii and A. agilis; the broad-toothed rat, Mastacomys fuscus; and the mountain pygmy possum, Burramys parvus. Although hair tubes have a number of limitations, such as not providing a measure of abundance or allowing the identification of individual animals, we believe that these limitations are balanced by the fact that the technique can be used at any spatial scale. Hair tubes are particularly suited to studies of animal distribution at the landscape-scale, because many hair tubes can be deployed and dispersed over large areas, and monitored on a regular basis by a small team of researchers. The technique also makes use of readily available, low-cost materials and could be easily adapted to a range of conditions and different target species.

To find routes and implement solutions to sustainable development will require relevant stakeholders from a broad range of societal groups to be involved. To create these routes will need radical ideas and profound visions because clearly current systems are not helping society towards sustainable development. This paper describes part of the SusHouse (Strategies towards the Sustainable Household) project which explored possible strategies for creating sustainable households based on a Factor 20 improvement in environmental efficiency by the year 2050. It describes so called 'Design Orienting Scenarios' (DOSs) using the case of 'shopping, cooking and eating' developed in Hungary, The Netherlands and the United Kingdom. The DOSs were developed from stakeholder creativity workshops with the aim of providing normative heuristic scenarios to illustrate a range of environmental futures, and thereby informing the design, business and policymaking processes. The variety of developed DOSs ensured that alternative futures were compared, each having concrete proposals for product-service systems. This paper also indicates that the methodological approach has potential for application to other research projects and particularly to design processes that aim to generate products for sustainable futures based on interactive stakeholder participation.

This paper compares the macro- and micro- analyses of techno-economic change. Arguing for perspectives which are sensitive to the local flexibility of innovation but which can also provide suggestions for policy and intervention, it describes and reviews the two major contributions: work on Techno-Economic Networks, and on Techno-Economic Paradigms. It is argued that the former has greater depth of analytical sensitivity, whilst the latter is more policy-relevant. Whilst there are approaches, such as Constructive Technology Assessment, which attempt to combine the two perspectives, these are seen as failing to retain sensitivity to the power differentials between key actors such as firms, experts, governing agencies or citizens' groups. The paper concludes by advocating attention to the ‘meso-level techno-economic’—the networks of institutions and actors at work in: geographically bounded systems of innovation; scientific and technological disciplines; firms, their strategies and linkages; and the nexus between production and consumption.