Future climate warming and changes to mountain permafrost in the Bolivian Andes

Water resources in many of the world’s arid mountain ranges are threatened by climate change, and in parts of the South American Andes this is exacerbated by glacier recession and population growth. Alternative sources of water, such as more resilient permafrost features (e.g. rock glaciers), are expected to become increasingly important as current warming continues. Assessments of current and future permafrost extent under climate change are not available for the Southern Hemisphere, yet are required to inform decision making over future water supply and climate change adaptation strategies. Here, downscaled model outputs were used to calculate the projected changes in permafrost extent for a first-order assessment of an example region, the Bolivian Andes. Using the 0 °C mean annual air temperature as a proxy for permafrost extent, these projections show that permafrost areas will shrink from present day extent by up to 95 % under warming projected for the 2050s and by 99 % for the 2080s (under the IPCC A1B scenario, given equilibrium conditions). Using active rock glaciers as a proxy for the lower limit of permafrost extent, we also estimate that projected temperature changes would drive a near total loss of currently active rock glaciers in this region by the end of the century. In conjunction with glacier recession, a loss of permafrost extent of this magnitude represents a water security problem for the latter part of the 21st century, and it is likely that this will have negative effects on one of South America’s fastest growing cities (La Paz), with similar implications for other arid mountain regions

Widespread effects of climate change on local plant diversity

Human activity has sent many measures of biodiversity into long-term decline, and there are suggestions that the sheer scale of this impact is sufficient to consider the modern era as a geological epoch of its own, known as “The Anthropocene”. However, recent meta-analyses show that local alpha diversity is often stable or slightly increasing. Here, we show that the local alpha diversity (species richness) of plants found in quadrats and transects has increased the most in cooler regions of the world that have experienced the highest absolute changes (i.e., changes in either direction) in climate. The greatest statistical support is for the effects of precipitation change. On average, alpha diversity declined slightly (−4.2% per decade) in the third of sites that experienced the lowest precipitation change but increased (+10.8% per decade) in the third of sites with the highest precipitation change. These results suggest that the “perturbation” of local communities during climatic transitions increases the average number of species, at least temporarily, an effect likely to remain important as climate change continues

Fine-scale climate change: modelling spatial variation in biologically meaningful rates of warming

The existence of fine‐grain climate heterogeneity has prompted suggestions that species may be able to survive future climate change in pockets of suitable microclimate, termed ‘microrefugia’. However, evidence for microrefugia is hindered by lack of understanding of how rates of warming vary across a landscape. Here, we present a model that is applied to provide fine‐grained, multidecadal estimates of temperature change based on the underlying physical processes that influence microclimate. Weather station and remotely derived environmental data were used to construct physical variables that capture the effects of terrain, sea surface temperatures, altitude and surface albedo on local temperatures, which were then calibrated statistically to derive gridded estimates of temperature. We apply the model to the Lizard Peninsula, United Kingdom, to provide accurate (mean error = 1.21 °C; RMS error = 1.63 °C) hourly estimates of temperature at a resolution of 100 m for the period 1977–2014. We show that rates of warming vary across a landscape primarily due to long‐term trends in weather conditions. Total warming varied from 0.87 to 1.16 °C, with the slowest rates of warming evident on north‐east‐facing slopes. This variation contributed to substantial spatial heterogeneity in trends in bioclimatic variables: for example, the change in the length of the frost‐free season varied from +11 to −54 days and the increase in annual growing degree‐days from 51 to 267 °C days. Spatial variation in warming was caused primarily by a decrease in daytime cloud cover with a resulting increase in received solar radiation, and secondarily by a decrease in the strength of westerly winds, which has amplified the effects on temperature of solar radiation on west‐facing slopes. We emphasize the importance of multidecadal trends in weather conditions in determining spatial variation in rates of warming, suggesting that locations experiencing least warming may not remain consistent under future climate change

A Modest Addendum to the English Sediment Core Meta-Database

Compilations of previous studies provide researchers with a source of valuable secondary data for re-analysis, an access route to identify relevant literature and an opportunity to systematically evaluate the research which is conducted and published. Recently Suggitt et al. (2015 Veg Hist Archbot 24, 743–747) presented a valuable compilation of core records for England. Here we present an extended version of this English Sediment Core Meta-database which includes data for 100 additional cores and improves the consistency of presentation. Despite these additions there are clearly large gaps remaining. Maximising the value of such meta-databases requires a community effort and we hope that this contribution will be a first step towards achieving this

Microclimate affects landscape level persistence in the British Lepidoptera

Microclimate has been known to drive variation in the distribution and abundance of insects for some time. Until recently however, quantification of microclimatic effects has been limited by computing constraints and the availability of fine-scale biological data. Here, we tested fine-scale patterns of persistence/extinction in butterflies and moths against two computed indices of microclimate derived from Digital Elevation Models: a summer solar index, representing fine-scale variation in temperature, and a topographic wetness index, representing fine-scale variation in moisture availability. We found evidence of microclimate effects on persistence in each of four 20 × 20 km British landscapes selected for study (the Brecks, the Broads, Dartmoor, and Exmoor). Broadly, local extinctions occurred more frequently in areas with higher minimum or maximum solar radiation input, while responses to wetness varied with landscape context. This negative response to solar radiation is consistent with a response to climatic warming, wherein grid squares with particularly high minimum or maximum insolation values provided an increasingly adverse microclimate as the climate warmed. The variable response to wetness in different landscapes may have reflected spatially variable trends in precipitation. We suggest that locations in the landscape featuring cooler minimum and/or maximum temperatures could act as refugia from climatic warming, and may therefore have a valuable role in adapting conservation to climatic change

Climate, landscape, habitat, and woodland management associations with hazel dormouse Muscardinus avellanarius population status

Although strictly protected, populations of the hazel dormouse Muscardinus avellanarius in the UK declined by 72% from 1993 to 2014. Using National Dormouse Monitoring Programme data from 300 sites throughout England and Wales, we investigated variation in hazel dormouse population status (expressed as Indices of Abundance, Breeding, and population Trend) in relation to climate, landscape, habitat, and woodland management. Dormice were more abundant and produced more litters on sites with warmer, sunnier springs, summers, and autumns. Dormouse abundance was also higher on sites with consistently cold local climate in winter. Habitat connectivity, woodland species composition, and active site management were all correlated with greater dormouse abundance and breeding. Abundances were also higher on sites with successional habitats, whereas the abundance of early successional bramble Rubus fruticosus habitat, woodland area, and landscape connectivity were important for population stability. Diversity in the structure of woodlands in Europe has decreased over the last 100 years, and the habitats we found to be associated with more favourable dormouse status have also been in decline. The conservation status of the hazel dormouse, and that of woodland birds and butterflies, may benefit from reinstatement or increased frequency of management practices, such as coppicing and glade management, that maintain successional and diverse habitats within woodland

Can microclimate offer refuge to an upland bird species under climate change?

Context: Climate change is a severe threat to biodiversity. Areas with a high variety of microclimates may provide opportunities for species to persist in a changing climate. Objectives: Test the extent to which microclimate is an important determinant of the distribution of a widespread upland passerine, the meadow pipit Anthus pratensis, and whether microclimate becomes an increasingly important determinant of distribution towards the warm edge of the species’ range. Methods: We used models of the occurrence of meadow pipits based on data from an extensive survey to identify macroclimate and topographic associations, the latter as proxies of microclimate. We assessed magnitude and direction of the effects of microclimate and whether the magnitude of microclimate effects increases as macroclimate suitability declines. Results: The probability of meadow pipit occurrence is significantly correlated with macroclimate and microclimate. Microclimate accounts for about a third of the variation in occupancy probability and has a stronger effect than macroclimate at all three spatial scales considered. Elevation and topographical wetness index are positively correlated with meadow pipit occurrence, while insolation is negatively correlated. Elevation and macroclimate suitability show a positive interaction, while insolation and macroclimate suitability show a negative interaction. Conclusions: Microclimate substantially influences the distribution of the meadow pipit. For high latitude and upland species such as this, suitable areas on cool slopes could form the focus for conservation protection, as these areas are likely to become increasingly utilised and may remain the only locations occupied in otherwise unsuitable climate

Testing the effectiveness of the Forest Integrity Assessment: a field-based tool for estimating the condition of tropical forest

1. Global targets to halt biodiversity losses and mitigate climate change will require protecting rainforest beyond current protected area networks, necessitating responsible forest stewardship from a diverse range of companies, communities and private individuals. Robust assessments of forest condition are critical for successful forest management, but many existing techniques are highly technical, time-consuming, expensive, or require specialist knowledge. 2. To make assessment of tropical forests accessible to a wide range of actors, many of whom may be limited by resources or expertise, the High Conservation Value Resource Network (HCVRN), with the SE Asia Rainforest Research Partnership (SEARRP), developed a South East Asian version of the Forest Integrity Assessment (FIA) tool as a rapid (< 1 hour) method of assessing forest condition in the field, where non-experts respond to 50 questions about characteristics of the local environment while walking a site transect. Here, we examined the effectiveness of this survey tool by conducting ~ 1,000 assessments of forest condition at 16 tropical rainforest sites with varying levels of disturbance in Sabah, Malaysian Borneo. 3. We found good agreement (R-squared range: 0.50 – 0.78) between FIA survey scores and independent measures of forest condition, including biodiversity, vegetation structure, aboveground carbon, and other key metrics of ecosystem function, indicating that the tool performed well. Although there was variation among assessor responses when surveying the same forest sites, assessors were consistent in their ranking of those sites, and prior forest knowledge had a minimal effect on the FIA scores. Revisions or further training for questions where assessors disagree, for example on the presence of fauna at a site, could improve consistency. 4. We conclude that the FIA survey tool is a robust method of assessing forest condition, providing a rapid and accessible means of forest conservation assessment. The FIA tool could be incorporated into management practices in a wide range of forest conservation schemes, from sustainability standards, to community forestry and restoration initiatives. The tool will enable more organisations and individuals to understand the conservation value of the forests they manage, and to identify areas for targeted improvements