Plants as indicators of snow layer duration in southern Norwegian mountains

The main aim of this paper was to study the responses of mountain plants in relation to the time of snowmelt. Three mountain areas situated along an oceanic–continental gradient were selected as study sites, and the sample plots ranged from 182 m below to 473 m above the climatic forest limit. In total, 185 quadrats (2 m × 2 m), stratified to include only oligotrophic and mesotrophic mountain vegetation types, were selected to represent a topographic range along altitudinal gradients. In each quadrat, the percentage groundcover of the species was recorded. From the beginning of April until July 2004, snow thickness was monitored, and the Julian day when the snow had completely melted was determined for all plots. The relationship between species abundances and Julian day of snowmelt were analysed by two different numerical methods: (1) relative values for species optimum and tolerance were given by Detrended Canonical Correspondence Analysis (DCCA) with Julian day of snowmelt as the constraining variable. (2) Species responses were modelled by Generalized Linear Models (GLM). For species with significant unimodal responses, optimum and tolerance were calculated. For species with significant linear models, different species response models were identified by the regression intercepts. One hundred and twenty six species (taxa) were tested, and 103 evidenced statistically significant (p < 0.05) distribution responses. Several common alpine plants had a distribution that appeared to be independent of snow. On the basis of the results of the numerical methods, the species were separated into nine Snow Indicator (SI) classes, as a parallel to the Ellenberg indicator values. The species’ SI values were used to calculate weighted average SI values to examine the relationships between previously described plant communities and vegetation transects which experience different snow conditions.     

Airborne hyperspectral data predict Ellenberg indicator values for nutrient and moisture availability in dry grazed grasslands within a local agricultural landscape

Species-based ecological indices, such as Ellenberg indicators, reflect plant habitat preferences and can be used to describe local environment conditions. One disadvantage of using vegetation data as a substitute for environmental data is the fact that extensive floristic sampling can usually only be carried out at a plot scale within limited geographical areas. Remotely sensed data have the potential to provide information on fine-scale vegetation properties over large areas. In the present study, we examine whether airborne hyperspectral remote sensing can be used to predict Ellenberg nutrient (N) and moisture (M) values in plots in dry grazed grasslands within a local agricultural landscape in southern Sweden. We compare the prediction accuracy of three categories of model: (I) models based on predefined vegetation indices (VIs), (II) models based on waveband-selected VIs, and (III) models based on the full set of hyperspectral wavebands. We also identify the optimal combination of wavebands for the prediction of Ellenberg values. The floristic composition of 104 (4 m × 4 m grassland) plots on the Baltic island of Öland was surveyed in the field, and the vascular plant species recorded in the plots were assigned Ellenberg indicator values for N and M. A community-weighted mean value was calculated for N (mN) and M (mM) within each plot. Hyperspectral data were extracted from an 8 m × 8 m pixel window centred on each plot. The relationship between field-observed and predicted mean Ellenberg values was significant for all three categories of prediction models. The performance of the category II and III models was comparable, and they gave lower prediction errors and higher R² values than the category I models for both mN and mM. Visible and near-infrared wavebands were important for the prediction of both mN and mM, and shortwave infrared wavebands were also important for the prediction of mM. We conclude that airborne hyperspectral remote sensing can detect spectral differences in vegetation between grassland plots characterised by different mean Ellenberg N and M values, and that remote sensing technology can potentially be used to survey fine-scale variation in environmental conditions within a local agricultural landscape.     

Abandonment of traditionally managed mesic mountain meadows affects plant species composition and diversity

In recent years abandonment of traditional management of mountain grasslands has been observed throughout Central Europe. However, the impact of abandonment on vegetation of mountain grasslands is still unclear. In this study it was hypothesized that the cessation of traditional management of mesic mountain meadows causes changes in their species composition and a decrease in the biodiversity. In total, 260 plots were established in the Sudetes (SW Poland) on meadows with regular annual mowing, meadows with irregular mowing management, and abandoned meadows. Relevés (5 × 5 m) were performed, and the habitat properties were determined using Ellenberg indicator values. The study confirmed the hypothesis that the various ways of extensive management have an influence on species richness. The lowest species richness was observed on the irregularly managed meadows, while higher species numbers were found on the abandoned and regular managed meadows. The majority of patches on abandoned meadows exhibited degradation through the expansion of Solidago gigantea, Solidago canadensis, Lupinus polyphyllus, Heracleum sosnovsky, Calamagrostis epigejos, Deschampsia flexuosa, Festuca rubra and Hypericum maculatum. Meadows subjected to different management practices differed significantly in Ellenberg indicator values. The abandoned meadows had the highest values of the light index (L) and nitrogen availability (N), whereas the highest values of soil moisture (F) were noted on the irregularly managed meadows. The degradation of mountain mesic meadows requires regular mowing management, which stops ecological succession and preserves their high biodiversity.     

Altitude modifies species richness–nutrient indicator value relationships in a country-wide survey of grassland vegetation

Nutrient enrichment is a threat to botanical diversity in Europe, and its assessment is part of biodiversity monitoring schemes. In Switzerland, this is done by calculating the average nutrient (N) indicator value of the vegetation based on a country-wide systematic vegetation survey. However, it is questionable whether N values indicate eutrophication and resulting species loss equally well across an entire country, which includes wide topographic gradients and distinct biogeographic regions. Here we analyze vascular plant species lists from 415 grassland plots (10 m²) between 365 and 2770 m a.s.l. throughout Switzerland to investigate how the relationship between N value and species richness differs with altitude and among regions. The N value strongly decreased with altitude (piecewise regression: r² = 0.77), particularly between 800 and 2000 m a.s.l., where this decrease was related to a decreasing proportion of fertilized grasslands. In the alpine belt, lower N values were associated with a greater frequency of acidic soils and a restricted species pool. Vascular plant species richness was maximal at intermediate altitude (piecewise regression: r² = 0.33) and intermediate N value (polynomial regression: r² = 0.46). When analyzed separately by altitudinal belt, the relationship between species richness and N value was negative in the lowlands and montane belt but unimodal in the subalpine belt. In the alpine belt, soil pH (R indicator values) explained most of the variation in species richness. Two indices of between-plot diversity (floristic dissimilarity and the contribution of individual plots to total species richness) were negatively related to N values from the lowlands to the subalpine belt but not in the alpine belt. All relationships differed little among the biogeographic regions of Switzerland, but they might be modified by changes in management and by the expansion of common lowland species into mountain grasslands.     

The altitudinal gradient of vascular plant richness in Aurland, western Norway

Differences in vascular plant species richness; along the altitudinal gradient in the Aurland area of western Norway have been investigated. Based on field surveys, as complete lists as possible of all vascular plants have been compiled for each 100 m altitudinal band, from sea level to the highest mountain (1764 m). For each of the 18 altitudinal bands, climatic data have been estimated. A total of 444 vascular plant species were recorded. Highest species richness (263 species) occurred in the 600–700 in band, whereas the uppermost band had only 10 species. There are minor differences in species number between the altitudinal bands < 1000 m. Partial least squares regression shows that species richness for the overall altitudinal gradient is well predicted by mean July and January temperatures and mean annual precipitation. Species turnover is highest in the 100–200 m. 600–700 m. and 1400–1500 m altitudinal bands. In terms of the gradient in summer temperature, the study supports the generally assumed linear relationship between July temperature and the number of vascular plant species between 700 and 1500 m corresponding with a mean July temperature range of 7–11°C. The study shows a decrease of ca 30 vascular plant species with a 1°C decrease in mean July temperature, and that the “climatic vascular plant limit” is here estimated to occur at a mean July temperature of 2.4°C. Above 1500 and below 700 m. species number is lower than expected based on summer iemperature conditions alone. The 700–800 m band represents the highest floristic difference compared to the other bands. Ordination and classification analyses of the floristic compositional data of all the bands highlight the 600–800 and 1500–1600 m altitudinal bands as the major biotic boundaries along the gradient. No major discontinuity in species richness, composition, or turnover was consistently found, however, at the 1100–1200 m band representing the forest-limit ecotone in Aurland.     

Life forms,leaf size spectra,regeneration capacity and diversity of plant species grown in the Thandiani forests,district Abbottabad,Khyber Pakhtunkhwa,Pakistan

The life form and leaf size spectra of plant species of the Thandiani forests, district Abbottabad, were studied during the summer of 2013. These forests host 252 plant species of 97 families. Biological spectra showed that Hemicryptophytes (80 spp., 31.74%) were dominant followed by Megaphanerophytes (51 spp., 20.24%), Therophytes (49 spp., 19.44%) and Nanophanerophytes (45 spp., 17.86). Hemicryptophytes are the indicators of cold temperate vegetation. At the lower elevations, Megaphanerophytes and Nanophanerophytes were dominant which confirm trees as dominant habit form due to high soil depth, moisture and temperature factors. Data on Leaf spectra in the area showed that Microphyllous (88 spp., 34.92%) species were dominant followed by Leptophyllous (74 spp., 29.36%) and Nanophyllous (60 spp., 23.80%). The Microphyllous plants again are the indicator of cold temperate zone as the area is situated at an elevation of 1191–2626 m. Similarly, Nanophylls were dominant at lower elevations. Data on family importance values and diversity among various communities were also recorded. Life form and Leaf spectra studies could be used to understand the micro climatic variation of the region.     

Optimizing the bioindication of forest soil acidity,nitrogen and mineral nutrition using plant species

Soil moisture and nutritional characteristics are frequently assessed using plant species and community bioindication, e.g., the Ellenberg system of species indicator values. This method, based on complete inventories of plant species present in plots, is time-consuming, which could prevent its general use for forest or other natural land management. Our aim was to determine the impact of a reduction in the time spent to carry out a floristic inventory on the quality of soil characteristic assessment using plant bioindication. We compared the measurements of soil pH-H₂O (pH), organic carbon to total nitrogen ratio (C:N) and base saturation (BS) in the 0–5 cm soil layer of 470 plots with the same variables estimated from floristic inventories of increasing duration, using plant indicator values (IV) from the EcoPlant database. The performance of predictions was evaluated by the square of the linear correlation coefficient between measured and predicted values (R²) and the root mean square error (RMSE) of predictions.The number rather than the percentage of total plot species used for the estimations was determinant for the prediction of soil pH quality. Performance of bioindication of pH, BS and C:N reached the maximum R² using the first 20–25 species recorded per plot, corresponding to a 14-min-long floristic inventory in comparison to a mean of 28 min spent to carry out a complete floristic inventory. A precision of prediction of 80% of the maximal precision was obtained after 4–5 min (6–12 inventoried species) for the three studied variables. These results are independent of the nutritional capability of the soils and were similar at the national and local scales. In order to estimate soil nutritional resources by plant bioindication, it is feasible to significantly reduce the time spent on floristic inventories and, thus, their cost. This is especially useful when the goal is to map the soil quality for decision-making in forest management.     

Effects of simulated warming on soil ammonia-oxidizing bacteria and archaea communities in an alpine forest of western Sichuan,China

Ongoing climate change, characterized by winter warming, snow cover decline and extreme weather events, is changing terrestrial ecosystem processes in high altitude and latitude regions. Winter soil processes could be particularly sensitive to climate change. In fact, winter warming and snow cover decline are interdependent in cold biomes, and have a synergistic effect on soil processes. Soil microorganisms not only play crucial roles in material cycling and energy flow, but also act as sensitive bio-indicators of climate change. However, little information is available on the effect of winter warming on forest soil ammonia-oxidizing bacteria (AOB) and archaea (AOA). The alpine and subalpine forest ecosystems on the eastern Tibet Plateau have important roles in conserving soil, holding water, and maintaining biodiversity. To understand the changes in AOB and AOA communities under climate change scenarios, an altitudinal gradient experiment in combination with soil column transplanting was conducted at the Long-term Research Station of Alpine Forest Ecosystems, which is situated in the Bipeng Valley of Lixian County, Sichuan, China. Thirty intact soil columns under an alpine forest at an altitude of 3582 m were transplanted and incubated at 3298 m and 3023 m forest sites, respectively. Compared with the 3582 m, we expected air temperature increases of 2 °C and 4 °C at the 3298 m and 3023 m, respectively. However, the temperatures in the soil organic layer (OL) and mineral soil layer (ML) increased by 0.27 °C and 0.13 °C, respectively, at 3023 m and ? 0.36 °C and ? 0.35 °C at 3298 m. Based on a previous study and with simultaneous monitoring of soil temperature, the abundances of AOB and AOA communities in both the OL and ML were measured by qPCR in December 2010 (i.e., the onset of the frozen soil period) and March 2011 (i.e., the late frozen soil period). The soil columns incubated at 3023 m had relatively higher AOB abundances and lower AOA/AOB ratios than those at 3298 m, while higher AOA abundances and AOA/AOB ratios were observed at 3298 m. The abundance of the microbial community at the late frozen period was higher than that at the onset of frozen soil, and the changes in microbial community abundance at the late frozen period were more substantial. Furthermore, the nitrate nitrogen (N) concentrations in both the OL and ML were significantly higher than ammonia N concentrations, implying that soil nitrate N is the primary component of the inorganic N pool in the alpine forest ecosystem. Additionally, the responses of AOA and AOB in the soil OL to soil column transplanting were more sensitive than the responses of those in ML. In conclusion, climate warming alters the abundance of the ammonia-oxidizing microbial community in the alpine forest ecosystem, which, in turn, might affect N cycling.     

Changes in the surface roughness of snow from millimetre to metre scales

The roughness of snow influences the movement of air across the snow surface and resulting transfers of energy. Here we focus on the roughness of the snowpack surface to determine its range of variability for different snow conditions (e.g., time since last snowfall), across spatial scales that ranged from 0.01 cm (card) to more than 1000 cm (transect) or more than 5-orders of magnitude, and due to the deposition of aeolian constituents. Digital photogrammetry of snow surfaces was used to compute two roughness metrics at two mountain sites in north-central Colorado. These metrics are the random roughness (RR) that disregards the spatial structure and the fractal dimension (D) computed from variogram analysis.At the crystal scale, D is between 1.67 (card) and 1.60 (board), which increases to 1.77 between 0.1 and 1.0 cm. At longer scales, D is 1.53 (board) to 1.56 (transect). There was no significant change in surface roughness during the accumulation season, with RR values at about 0.002. During the melt season the surface roughness doubled, with the RR values increasing from about 0.002 to 0.004. Snow was more rough parallel to the wind when dunes were present, and roughness varied spatially. The average RR value computed for the white snow surface of 0.014 is substantially greater than the value computed for the red dust surface of 0.0032. Due to undulations of smaller amplitude and as a result of the dust itself, the red dust surface is more random (D is 2.62 versus 2.23 for the white snow). Our results show that there is consistency in roughness over different scales, yet large scale processes (e.g., wind and radiation activity) influence the magnitude of roughness metrics much more than small scale processes (e.g., crystal form and metamorphism).     

Altitudinal variation in lifespan of Drosophila melanogaster populations from the Firtina Valley,northeastern Turkey

Studies of altitudinal changes in phenotype and genotype can complement studies of latitudinal patterns and provide evidence of natural selection in response to climatic factors. In Drosophila melanogaster, latitudinal variation in phenotype and genotype has been well studied, but altitudinal patterns have rarely been investigated. We studied populations from six different altitudes varying between 35 m and 2173 m in the Firtina Valley in northeastern part of Turkey to evaluate clinal trends in lifespan under experimental conditions. Lifespan in the D. melanogaster populations was examined in relation to altitude, sex, temperature (25 °C and 29 °C), and dietary yeast concentration (5 g/L and 25 g/L). As expected high temperature decrease lifespan in all populations. However, it was shown that lifespan was slightly affected by dietary stress. We found that lifespan decreases significantly under thermal stress conditions with increasing altitude. Moreover, there was a slightly negative relationship between altitude and lifespan, which was closely associated with climatic factors such as temperature and precipitation, may suggest local adaptation to climate.     

Vegetation mapping and multivariate approach to indicator species of a forest ecosystem: A case study from the Thandiani sub Forests Division (TsFD) in the Western Himalayas

QuestionsDoes the plant species composition of Thandiani sub Forests Division (TsFD) correlate with edaphic, topographic and climatic variables? Is it possible to identify different plant communities in relation to environmental gradients with special emphasis on indicator species? Can this approach to vegetation classification support conservation planning?LocationThandiani sub Forests Division, Western Himalayas.MethodsQuantitative and qualitative characteristics of species along with environmental variables were measured using a randomly stratified design to identify the major plant communities and indicator species of the Thandiani sub Forests Division. Species composition was recorded in 10 × 2.5 × 2 and 0.5 × 0.5 m square plots for trees, shrubs and herbs, respectively. GPS, edaphic and topographic data were also recorded for each sample plot. A total of 1500 quadrats were established in 50 sampling stations along eight altitudinal transects encompassing eastern, western, northern and southern aspects (slopes). The altitudinal range of the study area was 1290 m to 2626 m above sea level using. The relationships between species composition and environmental variables were analyzed using Two Way Cluster Analysis (TWCA) and Indicator Species Analysis (ISA) via PCORD version 5.ResultsA total of 252 plant species belonging to 97 families were identified. TWCA and ISA recognized five plant communities. ISA additionally revealed that mountain slope aspect, soil pH and soil electrical conductivity were the strongest environmental factors (p ≤ 0.05) determining plant community composition and indicator species in each habitat. The results also show the strength of the environment-species relationship using Monte Carlo procedures.ConclusionsAn analysis of vegetation along an environmental gradient in the Thandiani sub Forests Division using the Braun-Blanquet approach confirmed by robust tools of multivariate statistics identified indicators of each sort of microclimatic zones/vegetation communities which could further be used in conservation planning and management not only in the area studied but in the adjacent regions exhibit similar sort of environmental conditions.     

Improving and evaluating the soil cover indicator for agricultural land in Canada

A soil cover days (SCD) model has been developed by Agriculture and Agri-Food Canada for use as an agri-environmental indicator to monitor the relationship between agricultural production activities and agri-environmental quality. The SCD indicator integrates information on crops, soils, climate, and field activities to estimate the total equivalent number of days that agricultural soils are covered by crop canopy, crop residue and snow in a given year. Daily cover fractions of plant and residue for a given crop in an ecoregion are simulated using typical crop calendar and field management practices, and the equivalent number of days that soil is covered by snow in winter is derived from long term climate normals. The equivalent SCD for a spatial unit is then derived as the area-weighted sum of different crops and different management practices within the unit. This paper presents the SCD framework, details an assessment of the accuracy of the model and outlines future improvements. Annual snow days derived from 30-year climate normals as used in the model was strongly correlated (excluding mountain areas) with that derived from satellite data (R² = 0.45, n = 48), even though the remote sensing product showed significant temporal and spatial variability. Crop residue fraction estimated by the model was strongly correlated with field data collected over major crop areas and crop types (R² = 0.74, n = 55), and modelled plant cover fraction was well correlated with that derived from remote sensing data (R² = 0.57, n = 57). Large discrepancies were observed for some samples due to deviation of the actual crop calendar from that estimated using climate normals. National map showing the change in the indicator from 1981 to 2011 reveals changes in crop and residue management practices.     

Indoxyl sulfate promotes cardiac fibrosis with enhanced oxidative stress in hypertensive rats

AimsCardiovascular disease (CVD) is common in chronic kidney disease (CKD) patients. Indoxyl sulfate (IS) is a nephrovascular uremic toxin that induces oxidative stress in kidney and vascular system. The present study aimed to examine the effect of IS on fibrosis and oxidative stress in rat heart.Main methodsThe effects of IS on heart were examined by Masson's trichrome (MT) staining and immunohistochemistry using: (1) Dahl salt-resistant normotensive rats (DN), (2) Dahl salt-resistant normotensive IS-administered rats (DN + IS), (3) Dahl salt-sensitive hypertensive rats (DH), and (4) Dahl salt-sensitive hypertensive IS-administered rats (DH + IS).Key findingsDH + IS rats showed significantly increased heart weight and left ventricle weight compared with DN. DH and DH + IS rats showed significantly increased diameter of cardiomyocytes, increased MT-positive fibrotic area, increased staining for transforming growth factor (TGF)-β1, α-smooth muscle actin (SMA), type 1 collagen, NADPH oxidase Nox 4, malondialdehyde (MDA), and 8-hydroxydeoxyguanosine (8-OHdG) and decreased staining for nuclear factor (erythroid-derived 2)-like 2 (Nrf2) and heme oxygenase-1 (HO-1) in the heart compared with DN. More notably, DH + IS rats showed significantly increased diameter of cardiomyocytes, increased fibrotic area, increased staining for TGF-β1, SMA, type 1 collagen, Nox4, 8-OHdG and MDA, and decreased staining for Nrf2 and HO-1 in the heart compared with DH.SignificanceIS aggravates cardiac fibrosis and cardiomyocyte hypertrophy with enhanced oxidative stress and reduced anti-oxidative defense in hypertensive rats.     

Indoxyl sulfate upregulates renal expression of MCP-1 via production of ROS and activation of NF-κB, p53, ERK, and JNK in proximal tubular cells

AimsMonocyte chemotactic protein-1 (MCP-1) plays an important role in recruiting monocytes/macrophages to injured tubulointerstitial tissue. The present study examined whether indoxyl sulfate, a uremic toxin, regulates renal expression of MCP-1.Main methodsThe effect of indoxyl sulfate on the expression of MCP-1 was determined using human proximal tubular cells (HK-2 cells) and following animals: (1) Dahl salt-resistant normotensive rats (DN), (2) Dahl salt-resistant normotensive indoxyl sulfate-administered rats (DN + IS), (3) Dahl salt-sensitive hypertensive rats (DH), and (4) Dahl salt-sensitive hypertensive indoxyl sulfate-administered rats (DH + IS).Key findingsDN + IS, DH, and DH + IS rats showed significantly increased mRNA expression of MCP-1 in the kidneys compared with DN rats. DH + IS rats tended to show increased mRNA expression of MCP-1 in the kidneys compared with DH rats. Immunohistochemistry demonstrated the stimulatory effects of indoxyl sulfate on MCP-1 expression and monocyte/macrophage infiltration in the kidneys. Indoxyl sulfate upregulated mRNA and protein expression of MCP-1 in HK-2 cells. Indoxyl sulfate induced activation of ERK, p38, and JNK as well as of NF-κB and p53 in HK-2 cells. An antioxidant, and inhibitors of NF-κB, p53, ERK pathway (MEK1/2), and JNK suppressed indoxyl sulfate-induced mRNA expression of MCP-1 in HK-2 cells.SignificanceIndoxyl sulfate upregulates renal expression of MCP-1 through production of reactive oxygen species (ROS), and activation of NF-κB, p53, ERK, and JNK in proximal tubular cells. Thus, accumulation of indoxyl sulfate in chronic kidney disease might be involved in the pathogenesis of tubulointerstitial injury through induction of MCP-1 in the kidneys.     

Pattern of ant diversity in Korea: An empirical test of Rapoport's altitudinal rule

Two diversity patterns (hump-shaped and monotonic decrease) frequently occur along altitude or latitude gradients. We examined whether patterns of ant species richness along altitudes in South Korea can be described by these patterns and whether ranges of ant species follow Rapoport's altitudinal rule. Ants on 12 high mountains (> 1100 m) throughout South Korea (from 33° N to 38° N) were surveyed using pitfall traps at intervals of 200–300 m altitude. The temperatures at the sampling sites were determined from digital climate maps. Ant species richness decreased monotonically along the altitudinal gradient and increased along the temperature gradient. However, species richness of cold-adapted species (highland species) showed a hump-shaped pattern along altitude and temperature gradients. The altitude and temperature ranges of ant species followed Rapoport's rule. Sampling site temperature ranges were significantly correlated with coldness. Therefore, Rapoport's rule can be explained by high cold-tolerance of species inhabiting high altitudes or latitudes.     

Effects of grazing abandonment and climate change on mountain summits flora: a case study in the Tatra Mts

Changes in the local flora of mountains are often explained by climate warming, but changes in grazing regimes may also be important. The aim of this study was to evaluate whether the alpine flora on summits in the Tatra Mts, Poland and Slovakia, has changed over the last 100 years, and if the observed changes are better explained by changes in sheep grazing or climate. We resurveyed the flora of 14 mountain summits initially investigated in the years 1878–1948. We used ordination methods to quantify changes in species composition. We tested whether changes in plant species composition could be explained by cessation of grazing and climate change, and whether these factors have influenced shifts in Ellenberg’s plant ecological indicator values and Raunkiaer’s life forms. Changes in alpine flora were greater on lower elevation summits, and lower on summits less accessible for sheep. More accessible summits were associated with a decrease in mean values of plant species’ light ecological indicator values over time, and a concurrent increase in temperature and nitrogen ecological indicator values. No significant relationships were found between accessibility for sheep and changes in Raunkiaer’s life-forms. Greater accessibility for sheep (meaning high historical grazing pressure) led to greater compositional changes of mountain summits compared with summits with low accessibility. Our results suggest that cessation of sheep grazing was the main factor causing changes in the species composition of resurveyed mountain summits in the Tatra Mts, while climate change played a more minor role.     

Potential impacts of climate warming on active soil organic carbon contents along natural altitudinal forest transect of Changbai Mountain

Understanding soil carbon fractions and their responses to the global warming is important for improving soil carbon management of natural altitudinal forest ecosystem. In this study, the contents of soil total organic carbon (SOC), soil labile organic carbon (LOC), and microbial biomass carbon (MBC) in soil upper layers (0–20 cm) were measured along a natural altitudinal transect in the north slope of Changbai Mountain. The results showed that under natural conditions the contents of SOC and LOC were largest in Betula ermanii forest (altitude 1996 m), moderate in spruce-fir forest (altitude 1350 m), and smallest in Korean pine mixed broad-leaf tree forest (altitude 740 m). MBC contents in different forest ecosystems decreased in the order of Betula ermanii forest, Korean pine mixed broad-leaf tree forest, and dark coniferous forest. In addition, the responses of SOC, LOC, and MBC to soil warming were conducted by relocating intact soil cores from high- to low-elevation forests for one year. As expected, the soil core relocation caused significant increase in soil temperature but made no significant effect on soil moisture. After one year incubation, soil relocation significantly decreased SOC contents, whereas the contents of LOC, MBC, and the ratios of LOC to SOC and MBC to SOC increased.     

Survival of rapidly fluctuating natural low winter temperatures by High Arctic soil invertebrates

The extreme polar environment creates challenges for its resident invertebrate communities and the stress tolerance of some of these animals has been examined over many years. However, although it is well appreciated that standard air temperature records often fail to describe accurately conditions experienced at microhabitat level, few studies have explicitly set out to link field conditions experienced by natural multispecies communities with the more detailed laboratory ecophysiological studies of a small number of ‘representative’ species. This is particularly the case during winter, when snow cover may insulate terrestrial habitats from extreme air temperature fluctuations. Further, climate projections suggest large changes in precipitation will occur in the polar regions, with the greatest changes expected during the winter period and, hence, implications for the insulation of overwintering microhabitats. To assess survival of natural High Arctic soil invertebrate communities contained in soil and vegetation cores to natural winter temperature variations, the overwintering temperatures they experienced were manipulated by deploying cores in locations with varying snow accumulation: No Snow, Shallow Snow (30 cm) and Deep Snow (120 cm). Air temperatures during the winter period fluctuated frequently between +3 and −24 °C, and the No Snow soil temperatures reflected this variation closely, with the extreme minimum being slightly lower. Under 30 cm of snow, soil temperatures varied less and did not decrease below −12 °C. Those under deep snow were even more stable and did not decline below −2 °C. Despite these striking differences in winter thermal regimes, there were no clear differences in survival of the invertebrate fauna between treatments, including oribatid, prostigmatid and mesostigmatid mites, Araneae, Collembola, Nematocera larvae or Coleoptera. This indicates widespread tolerance, previously undocumented for the Araneae, Nematocera or Coleoptera, of both direct exposure to at least −24 °C and the rapid and large temperature fluctuations. These results suggest that the studied polar soil invertebrate community may be robust to at least one important predicted consequence of projected climate change.     

Benchmarking the environmental performance of specialized milk production systems: selection of a set of indicators

Dairy production across the world contributes to environmental impacts such as eutrophication, acidification, loss of biodiversity, and use of resources, such as land, fossil energy and water. Benchmarking the environmental performance of farms can help to reduce these environmental impacts and improve resource use efficiency. Indicators to quantify and benchmark environmental performances are generally derived from a nutrient balance (NB) or a life cycle assessment (LCA). An NB is relatively easy to quantify, whereas an LCA provides more detailed insight into the type of losses and associated environmental impacts. In this study, we explored correlations between NB and LCA indicators, in order to identify an effective set of indicators that can be used as a proxy for benchmarking the environmental performance of dairy farms. We selected 55 specialised dairy farms from western European countries and determined their environmental performance based on eight commonly used NB and LCA indicators from cradle-to-farm gate. Indicators included N surplus, P surplus, land use, fossil energy use, global warming potential (GWP), acidification potential (AP), freshwater eutrophication potential (FEP) and marine eutrophication potential (MEP) for 2010. All indicators are expressed per kg of fat-and-protein-corrected milk. Pearson and Spearman Rho’s correlation analyses were performed to determine the correlations between the indicators. Subsequently, multiple regression and canonical correlation analyses were performed to select the set of indicators to be used as a proxy. Results show that the set of selected indicator, including N surplus, P surplus, energy use and land use, is strongly correlated with the eliminated set of indicators, including FEP (r = 0.95), MEP (r = 0.91), GWP (r = 0. 83) and AP (r = 0.79). The canonical correlation between the two sets is high as well (r = 0.97). Therefore, N surplus, P surplus, energy use and land use can be used as a proxy to benchmark the environmental performance of dairy farms, also representing GWP, AP, FEP and MEP. The set of selected indicators can be monitored and collected in a time and cost-effective way, and can be interpreted easily by decision makers. Other important environmental impacts, such as biodiversity and water use, however, should not be overlooked.     

Climate warming mediates range shift of two differentially adapted stenothermal Drosophila species in the Western Himalayas

The average temperature of the earth has increased from 0.3 to 0.6 °C, and warming is facilitating faunal reshuffling. Variable thermal environments warrant mechanisms to adjust the expression of phenotypic values to environmental needs. Ectothermic Drosophilids are profoundly affected by thermal selection (i.e., genetic effects) or through induced effects on phenotypes (i.e., plastic effects). Climatic data for the last fifty years involves a significant change in average temperature (T_ave) of Western Himalayas, which has affected the distribution and boundaries of various Drosophilids in this region. There is a significant decline in the number of D. nepalensis from lower ranges; whereas D. ananassae is reported to be introduced to lower to mid mountainous ranges. Further, a comparison of fecundity, hatchability, and viability at different growth temperatures has shown significant decrease in trait values at 17 °C in D. ananassae and at 25 °C in D. nepalensis. Thus, the recent range changes of these two species involve genetic effects on ecophysiological and plastic effects on life history traits. Our results indicate that thermal plasticity of life history traits can be species-specific; thus climate change may lead to a mismatch of such traits to the changing environment. We suggest that D. nepalensis and D. ananassae could serve as indicator species for analyzing range changes under changing climatic conditions. Evolutionary biologists can provide unique perspective to the examination of how climate change will affect the earth's biota.