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Dolines are depressions in karst landscapes that are of high value for conservation, providing habitats and supporting species not found in the surrounding landscape. This is due to their high microhabitat diversity and ability to decouple microclimate from regional climate changes, making them potential refugia for biodiversity. Nevertheless, local anthropogenic disturbances have had considerable impact on the species composition and vegetation structure of many dolines. Here we investigate the conservation value of dolines in three European karst areas, where different levels and types of anthropogenic disturbances have been shaping the vegetation for centuries, using the number of plant species that are cool-adapted, moist-adapted and of high conservation importance (i.e. vulnerable species) as indicators. We found that anthropogenic disturbances generally have a negative impact, reducing the number of vulnerable species supported by dolines. However, more cool-adapted and moist-adapted species were found in some dolines planted with non-native Picea abies than in less disturbed dolines, indicating that anthropogenic disturbances can also have positive consequences for biodiversity. We conclude that anthropogenic disturbances alter the capacity of dolines to support vulnerable species, and that this will impact survival of species in landscapes under global warming. In this context, the effects of various disturbances on species composition and diversity need to carefully considered to determine the best conservation and/or management options. [ABSTRACT FROM AUTHOR]

Refugia are key environments in biogeography and conservation. Because of their unique eco‐evolutionary formation and functioning, they should display distinct functional trait signatures. However, comparative trait‐based studies of plants in refugia and non‐refugia are lacking. Here, we provide a comparison between resource‐rich (putative microrefugia for species preferring mesic habitats under increasing aridity) and resource‐impoverished woodlands (non‐refugia) around two granite outcrops in south‐western Australia. We measured and compared six functional traits (bark thickness, foliar δ13C, foliar C:N, leaf dry matter content, plant height, specific leaf area) in four woody species. We performed multiple‐trait, multiple‐species and single‐trait, within‐species analyses to test whether plants in resource‐rich habitats were functionally distinct and more diverse than those in the surrounding resource‐impoverished woodlands. We found that species in resource‐rich woodlands occupied larger and distinct multiple‐trait functional spaces and showed distinct single‐trait values (for specific leaf area and bark thickness). This suggests that plants in resource‐rich woodlands can deploy unique and more diverse ecological strategies, potentially making these putative microrefugia more resilient to environmental changes. These findings suggest that species in microrefugia may be characterised by unique functional signatures, illustrating the utility of comparative trait‐based approaches to improve understanding of the functioning of refugia. [ABSTRACT FROM AUTHOR]

Abstract: Plants respond to changing environmental conditions, and their ability to adjust intra‐specifically to such shifts represents an ecological and evolutionary advantage. We studied seven plant traits for two common, rhizomatous granite outcrop species (the fern Cheilanthes austrotenuifolia, and the herb Stypandra glauca) with seasonal foliage during the cooler, wetter winter months at seven sites across an aridity gradient in southwestern Australia. We investigated trait patterns at regional and habitat scale, by investigating changes in trait values along the aridity gradient, and by comparing two different habitats types (sun‐exposed and sheltered). We expected plants occurring in more arid sites and highly irradiated, shallow‐soil (sun‐exposed) habitats, to exhibit traits indicative of more conservative resource acquisition, retention and use strategies. At the habitat scale, we found support for our prediction, with plants in more stressful, sun‐exposed habitats showing traits’ values associated with more conservative strategies (especially for water), such as smaller plants, denser leaves, higher foliar δ13C and C/N. However, at the regional scale many traits displayed the opposite pattern, suggesting less conservative resource acquisition in more arid sites. This evidence was particularly pronounced for specific leaf area (SLA), which exhibited a significant, positive relationship with increasing aridity. We suggest that the unexpected regional trends in foliar traits relate to shorter lived, faster growing leaves linked to highly efficient resource acquisition and use strategies during the shorter growing season in the more arid regions. These highly exploitative strategies may enable plants to avoid climate extremes, that is, hot and dry periods in the more arid sites. Our findings of contrasting foliar traits responses at different scales support the importance of multi‐scale approaches to quantify the role of intraspecific trait variability. [ABSTRACT FROM AUTHOR]

Species composition and life history traits of trees in native forests in the dry zone of Fiji were investigated. Areas receiving less than 2500 mm yr-1 of rain and covered with native forest were identified using maps, aerial photographs, estimated climate (WorldClim), and field reconaissance. Ten forest remnants were identified and species lists and data on natural history and disturbance were compiled. Cluster analysis and DECORANA identified two principal forest types, moist forest (MF) and tropical dry forest (TDF), each defined by unique climate, species composition, and tree life history characteristics. TDF (reported for the first time from Fiji) has a pronounced dry season (5 consecutive months with <100 mm rainfall each) and several deciduous canopy species. MF lacks a pronounced dry season and has few deciduous species. The amount and variability of rainfall seem to influence the type of forest in a particular location and disturbance is negatively correlated with precipitation. TDF are probably Fiji's most endangered ecosystems. [ABSTRACT FROM AUTHOR]

• 14 problematic invasive woody plants can be classified into 4 spatial patterns • Presence and abundance on urban-rural gradient type differs by plant species • Abundance of IWP is explained more by urban-rural gradient type than road type • IWP species may be common in urban sector type but not necessarily abundant • Overall abundance of target species in urban sector lower than other sectors Tropical Pacific island countries, many of which are less-developed, are experiencing invasions of alien plant species at rates faster than areas of comparable size elsewhere. In this paper we examine the relationship between the presence, abundance, and richness of 14 invasive woody plant (IWP) species and level of urbanization and road type in the Greater Suva Urban Area (GSUA), Fiji. One hundred and fifty-four sample locations within a 29 km transect traversing urban, peri-urban and rural land sectors on local, collector and arterial roads were surveyed. We analyzed the 14 species for frequency of occurrence across the urban-rural gradient and found spatial patterns of IWP presence differed by species. We analyzed the abundance of seven species using multivariable regression and found abundance was more often influenced by urban-rural sector than road type, though road type had a significant effect for some species. We conclude by offering plausible explanations for differences attributed to modes of dispersal, introduction history and human activities. We include supplementary material providing detailed characterization of biology, ecology, and history of the 14 target species. These findings are expected to help inform risk assessments and management of IWP in other tropical urban-rural gradients, and especially small island developing states. [ABSTRACT FROM AUTHOR]