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Loss of biodiversity is accelerating, including the loss of genetic diversity. Conservation of small, isolated populations may be important, as they can provide valuable contributions to overall genetic variation and long-term viability of species. Furthermore, such populations may play an essential role in adaptation to new environments following changes in e.g. land-use and climate. Dracocephalum ruyschiana is a threatened plant species throughout its European distribution, but 25% of the European populations are situated within Norway. Therefore, the species has its own action plan in Norway, which includes demographic monitoring. However, this monitoring does not cover genetic variation nor is the selection of monitored populations based on genetic differentiation, therefore this fundamental level of biodiversity is overlooked. We analyzed 43 sites using 96 SNPs developed for D. ruyschiana, to investigate whether the monitored populations cover the genetic variation and differentiation found within the Norwegian distribution. The results show structuring and differentiation between populations and indicate that there are at least four distinct genetic groups, of which only two are covered extensively by current demographic monitoring. We suggest that two sites representing the two other genetic groups should be included in the national monitoring program to better conserve the genetic variation found in the Norwegian population of D. ruyschiana. Overall, our results highlight the importance of an integrated, interdisciplinary framework to better monitor and conserve biodiversity at several levels.

Veteran trees are keystone structures currently in decline worldwide. In Europe, veteran oaks (Quercus spp.) are important habitat trees for wood-living beetles. Still, we have limited knowledge of the drivers determining the composition of these communities and the relevant spatial and temporal scales for these drivers. We collected beetles from 32 hollow oaks in two regions in Southern Norway along a coast-inland gradient paralleling historical onset of oak harvesting. We focused on species with different host-association to oak and identified the relative importance of processes working on different spatial scales, ranging from tree-scale to region-scale, as well as effects of the coast-inland gradient. We found all the spatial scales to influence the species composition, with a response to the coast-inland gradient and differences between the regions for all beetle groups. The tree scale was the most important scale for species mainly associated with oak, generalist species and the overall species composition—with bryophyte cover on the stem, depth of bark crevices and amount of wood mould as the most important variables. The close surroundings and forest variables on the landscape scale was most important for the beetle species restricted to broadleaf trees. Our study confirmed established knowledge, but also revealed new relationships between oak-associated beetles and relevant drivers on the tree and regional scale. As important responses of species mainly associated with oak or broadleaf trees were concealed when analyzing the total community, care should be taken not to base management recommendations on such overall, general patterns.

Habitat fragmentation resulting from anthropogenic land-use change may negatively affect both biodiversity and ecosystem structure and function. However, susceptibility to fragmentation varies between species and may be influenced by for instance specialization, functional traits and trophic level. We examined how total and specialist species richness, species composition and functional trait composition at two trophic levels (vascular plants and sap-feeding hoppers) vary with habitat fragmentation (patch size and connectivity) in dry calcareous grasslands in southeast Norway. We found that fragmentation affected plant and hopper species composition both totally and of habitat specialists, but with a net species loss only for the specialists, indicating greater susceptibility of specialized species. Reductions in patch size and increasing isolation negatively affected plant specialists with different sets of traits, effectively reducing the number of species with trait combinations suitable to persist in small and isolated patches. Fragmentation influenced trait composition of the total hopper community, but not of habitat specialists. A lesser degree of habitat association could explain why hoppers, despite belonging to a higher tropic level, seemed to be less susceptible to fragmentation than plants. Nonetheless, our study shows that habitat fragmentation affects both species richness, species composition and trait composition of plants and hoppers, indicating that fragmentation leads not only to a loss of species, but also alters dominance hierarchies and the functionality of grassland communities. Calcareous grasslands · Functional traits · Habitat fragmentation · Auchenorrhyncha · Vascular plants

Human disturbance in alpine habitats is expected to increase, and improved knowledge of short-term recovery after disturbance events is necessary to interpret vegetation responses and formulate planning and mitigation efforts. The ability of a plant community to return to its original state after a disturbance (community resilience) depends on species composition and environmental conditions. The aim of this study is to analyze initial short-term effects of disturbance in alpine plant communities in contrasting climates (oceanic vs. continental; central Norway). We used a nested block-design to examine vegetative regrowth and seedling recruitment after experimental perturbation. Three plant community types along the snow pack gradient were exposed to (1) no disturbance, (2) clipping, and (3) clipping and uprooting. Slow vegetative regrowth and low seedling establishment rates were found in dry alpine ridges and late-melting oceanic snowbed communities. Leeside habitats with intermediate snow conditions were found more resilient. The difference was related to growth form and species diversity. Woody species, which dominated in ridges and oceanic snowbeds, showed the most negative response to disturbance. Species-rich plant communities dominated by graminoids and herbs showed higher rates of regrowth. Species richness seems to cause resilience to the plant communities through higher response diversity. Plant communities at the extreme ends of abiotic gradients, ridges and late-melting snowbeds, will be most sensitive to both disturbance and environmental change. In an up-scaled human-used landscape disturbance effects will be amplified and further limit recovery to a pre-disturbance state.

An improved understanding of population-level consequences of grazing on plants can be facilitated by an assessment of grazing effects on all stages in the life-cycle. In this study, 6 years of demographic data for three populations of the perennial herb Geranium sylvaticum were analysed. We examined the effects of sheep grazing (high sheep density, low sheep density and no sheep) and interannual climatic variability on vital rates and population growth rates (λ). Grazing did not affect survival or flowering rates, but reduced rates of growth and increased rates of clonal reproduction. At the population level, high contributions from retrogression and clonal reproduction buffered reduced rates of growth and stasis, and no consistent differences in λ between populations exposed to different sheep densities were found. Instead, large between-year variability in λ, independent of sheep density, was detected, related to variation in the local summer climate. The results indicated, however, that grazing effects on λ were more severe in unfavourable than in normal years. Our study highlights that increased clonal reproduction rates functioned as a tolerance mechanism towards grazing in this herb, which forms a mechanism to explain how moderate population responses to grazing in some herbs can arise.

Colonisation is often a critical stage in the life history of plants, and recruitment success is expected to have a strong impact on plant frequencies especially among herbs. Several plant traits (seed size, plant height, leaf dry weight and specific leaf area) are suggested to be functionally important in early life stages, and the impact of such traits is expected to increase with habitat harshness. In this comparative study we examine the relative role of different plant traits for herb community patterns on both a local and regional scale in two contrasting alpine ecosystems in southern Norway: (1) a sub-continental region with more dry and productive, base-rich soils (Ho1, Hallingdal) and (2) an oceanic region, with humid acidic soils (Setesdal). Differences in species richness between regions were mainly due to higher herb richness in the base-rich region (n=55) than in the acidic region (n=13). Among traits, herb species seed weight was higher at the acidic site. The relative importance of traits for explaining herb local abundance and regional distribution tended to be stronger at the acidic site. No trait had a significant effect at the base-rich site, although seed weight and seed number were marginally non-significant. Plant clonality was positively related to local abundance and marginally to regional distribution at the acidic site. Plant frequency-trait correlations were generally higher in the acidic region then in the base-rich region. There was further a (marginal) increase of herbs with large seeds and with a dependence on sexual reproduction with increasing pH levels in Ho1. Soil pH was also the most important environmental variable for herb richness in Ho1, while no environmental variable was significantly related to herb richness in Setesdal. The study suggests that recruitment through seed is critical for the alpine herb community patterns especially in harsh habitats. Possible explanations for recruitment constraints include both soil acidity (low pH and Ca levels in addition to possible aluminium toxicity) and disturbance through grazing.

A simple isothermal calorimeter ideal to study hydration of cementitious systems is described together with an ampoule design to allow addition of water and mixing with the ampoule inside the calorimeter. An overview of dynamic corrections is given, and the utilisation of the different dynamic corrections on the calorimeter output is discussed. Correction of data on b-hemihydrate hydration to form gypsum has shown good kinetic agreement with data from synchrotron X-ray diffraction.