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Assessment of alpine summit flora in Kashmir Himalaya and its implications for long-term monitoring of climate change impacts
Abstract
In an era of climate change, the availability of empirical data on alpine summit vegetation in the Himalaya is still scarce. Here we report the assessment of alpine summit flora in Gulmarg Wildlife Sanctuary, Kashmir Himalaya. We employed a globally standardized Multi-Summit Approach and four spatially isolated summits spanning an elevation gradient of 210 m (between 3530-3740 m a.s.l.) from natural treeline to nival zone. Sampling of the summits was carried out in the year 2018 to collect floristic data together with records of soil temperature. A total of 142 vascular plant species were recorded in the sampled summits. Majority of the species were of herbaceous growth form and with perennial life span. Based on Raunkiaer's life form, hemicryptophytes were the most dominant followed by therophytes and phanerophytes. The summit flora showed the predominance of narrow-endemic species, with broad-and non-endemics declining with elevation. A significant relationship between growth form, Raunkiaer's life form, and the degree of endemism with elevation was observed. Both species diversity and soil temperature showed a monotonic decrease with increasing elevation. Interestingly, soil temperature clearly determined the magnitude of species diversity on the summits. Furthermore, based on floristic composition, the lowest summit had the highest dissimilarity with the rest of the summits. The present study employed globally standardized protocol to scientifically assess the patterns of plant diversity on the alpine mountain summits of Kashmir Himalaya, which in turn has wide implications towards long-term monitoring of climate change impact on alpine biodiversity in the rapidly warming Himalaya. Citation: Hamid M, Khuroo AA, Malik AH, et al. (2020) Assessment of alpine summit flora in Kashmir Himalaya and its implications for long-term monitoring of climate change impacts. Journal of Mountain Science 17.
... The vegetation in the sanctuary comprises of two major forest types; Himalayan dry temperate forest and subalpine forest followed by alpine grasslands at higher altitudes (Haq et al., 2020 . These subalpine forests are followed by alpine scrub and alpine meadows at higher altitudes (Hamid et al., 2020a). Wet meadow and dry heath communities dominate this landscape with shrub species such as Rhododendron anthopogon, Lonicera obovata, and forbs such as Bistorta affinis, Swertia petiolata, Dolomiaea macrocephala, and Primula macrophylla are the most common species (Hamid et al., 2020a). ...
... These subalpine forests are followed by alpine scrub and alpine meadows at higher altitudes (Hamid et al., 2020a). Wet meadow and dry heath communities dominate this landscape with shrub species such as Rhododendron anthopogon, Lonicera obovata, and forbs such as Bistorta affinis, Swertia petiolata, Dolomiaea macrocephala, and Primula macrophylla are the most common species (Hamid et al., 2020a). The sanctuary also provides critical habitat for several faunal species such as Cervus hanglu, Moschus cupreus, Capra sibrica and Panthera pardus. ...
... These differences in functional traits can be attributed to changes in microhabitat conditions such as temperature, precipitation, light, nutrient and water availability, and atmospheric pressure between the vegetation zones surveyed. In fact, over extremely small elevation distances, the three vegetation zones investigated hold significant heterogeneity in microclimatic conditions, soil characteristics, and light availability (Hamid et al., 2020a;Hamid et al., 2021;Gulzar et al., 2022). The Himalayan dry temperate forest zone, for example, is composed of large trees, and as a result, understory shrubs and herbs receive less light filtered by the forest canopy. ...
Compression of life zones along elevational gradients in mountains supports diverse vegetation types, and therefore offers ideal setting to study plant functional traits. Functional traits, the features that enable plants to live in varied environmental conditions, help in understanding ecological interactions, evolutionary adaptations, and predicting plant response to global change drivers. To date, little is known how the trait diversity varies across different growth forms and vegetation zones in mountains. Here, we aimed to investigate interspecific leaf trait variability among different growth forms and vegetation zones along a wide elevation gradient (2000–4200 m) in Kashmir Himalaya. We measured leaf functional traits (specific leaf area—SLA, leaf thickness — LT, leaf dry matter content —LDMC) of 76 plant species corresponding to three growth forms (trees, shrubs and herbs) and three vegetation zones (Himalayan dry temperate forests, subalpine forests and alpine grasslands). Our results revealed high trait variability across the regional species pool studied. We found significant variation in leaf functional traits among the different growth forms, with higher values of LT and LDMC recorded for woody species than herbaceous ones. Among different vegetation zones, the SLA was found to be significantly higher at lower to middle elevations, while the other leaf traits (LT and LDMC) showed an opposite trend. Across all the vegetative zones, we also found a negative correlation between SLA and the other leaf traits, and the latter showed a positive trait-trait correlation. Overall, our study contributes to a deeper understanding of trait-trait, trait-growth form and trait-vegetation zone relationships. Our findings suggest that the variation in leaf functional traits among different growth forms seems to be a trade-off mechanism between resource acquisition and leaf construction, and also help in identifying species' adaptive functional traits that are critical for plant survival in the face of ongoing climate change in the Himalaya.
... Treeline shifts can have both positive and negative feedbacks on mountain ecosystems by affecting local and regional climate, soil carbon storage potential, nutrient cycling, hydrological processes and biodiversity (Hartley et al., 2012;Lu et al., 2021). Therefore, understanding the floristic composition and patterns of species richness along treeline ecotone will be the first step in accurately estimating the warminginduced species' range shifts, distribution patterns, treeline expansion and also be crucial in recognizing the suite of species that will face one another in the future or have potential to invade alpine landscapes at higher elevations (Hamid et al., 2020b). ...
... This is followed by alpine scrub and alpine meadows at higher elevations which encompass an elevational range of 3600-3750 m a.s.l. The dominant vegetation in the alpine zone is mainly composed of Rhododendron-Juniperus and Sibbaldia-Polygonum plant assemblages (Hamid et al., 2020b(Hamid et al., , 2021. The second site (Sinthan) is a high-elevation mountain pass that connects the Daksum area of Brengi valley of Kashmir province in the Anantnag district to the Chatru area of Kishtwar district in the Jammu province. ...
... The chi-square test was used to estimate whether there is an association between the species trait and the plot studied and to evaluate how likely it is that any observed difference between these two arose by chance. Therefore, the observed number within each combination was compared with the counts expected based on equal distribution across the combinations (Hamid et al., 2020b). Pearson's residuals were used to indicate the difference between observed and expected values within each set. ...
Globally, the treelines at higher elevations in mountains are reported to be advancing up-slope in response to recent climate warming. However, little is known about the treeline advancement in the Himalaya due to paucity of baseline vegetation data with which to compare, thus making their assessment and monitoring challenging. To fill this knowledge gap, the present study documented floristic and functional diversity of two treeline ecotone sites in Kashmir Himalaya. At each site, we conducted field sampling by laying five 20-m2 plots, with one at the highest limit (T0 plot), two plots below and two above the treeline and two nested subplots of 5-m2 for shrubs and five 1-m2 for herbs in each plot. We recorded 97 plant species belonging to 33 families from the two sites. We observed a considerable difference in species composition and distribution along the treeline ecotone. Majority of the species reported were perennial herbs. We observed a significant association of growth forms with the particular plots along the treeline ecotone. At both the sites, we recorded highest species richness at the T0 plot which was correlated well with the functional traits, thus indicating convergence of floristic and functional diversity at this transition zone. Interestingly, the T0 plot at both the sites showed maximum overlap of species with the plots above and below the treeline. In an era of climate warming, our study provides crucial baseline data that will facilitate assessment and monitoring of the Himalayan treelines.
... These harsh climatic conditions are exacerbated by xeric conditions (Kala and Mathur, 2002;Rahman et al., 2020), which generally result in a very short growing season in the area. In comparison to annuals and biennials, a significant number of perennial plants were also found as they do in other alpine floras around the globe (Dvorský et al., 2011;Rundel, 2011;Brand et al., 2019;Hamid et al., 2020). Perennial plant species have the ability to store considerable amounts of total biomass belowground, where they play a vital role to overcome the harsh and long winter months (He et al., 2017;Lubbe et al., 2021). ...
... Sofi et al. Trees, Forests and People 7 (2022) 100213 also has been reported from mountains including Hindukush (Agakhanyantz and Breckle, 1995), Swiss alps (Matteodo et al., 2013) and Kashmir alpine summits (Hamid et al., 2020). ...
... These harsh climatic conditions are exacerbated by xeric conditions (Kala and Mathur, 2002;Rahman et al., 2020), which generally result in a very short growing season in the area. In comparison to annuals and biennials, a significant number of perennial plants were also found as they do in other alpine floras around the globe (Dvorský et al., 2011;Rundel, 2011;Brand et al., 2019;Hamid et al., 2020). Perennial plant species have the ability to store considerable amounts of total biomass belowground, where they play a vital role to overcome the harsh and long winter months (He et al., 2017;Lubbe et al., 2021). ...
... Sofi et al. Trees, Forests and People 7 (2022) 100213 also has been reported from mountains including Hindukush (Agakhanyantz and Breckle, 1995), Swiss alps (Matteodo et al., 2013) and Kashmir alpine summits (Hamid et al., 2020). ...
The impact of climate change on the mountain ecosystems globally can be better sensed through monitoring of
structural shifts in vegetation vis-`a-vis livelihoods of mountain communities. Here, we report the distribution
pattern of an ecologically vital species, Arnebia euchroma, and its co-occurring communities. The species is
considered as an indicator of ecosystem health and is linked to human wellbeing in mountain systems in the
Trans-Himalayan range of Ladakh. Through intensive field surveys for two years, we recorded 127 species
belonging to 41 families associated with A. euchroma across habitats, majority of which are herbaceous with
perennial life cycle. The hemicryptophytes were found to be the most dominant followed by the geophytes and
phanerophytes. Highest average importance value index (IVI) was found to be for A. euchroma (37.93) as against
very low IVI values for 41.73% of the total flora, which reflects the need for conservation. Our generalized linear
model results demonstrate the role of A. euchroma in maintaining and enhancing the maturity index of the
communities with increasing altitude. The low maturity index of the communities indicates the influence of
anthropogenic pressures and rather harsh environmental conditions. The Principal Component Analysis and
Cluster Analysis correlated the investigated communities geographic features and microclimates to identify the
dominant taxa and unique species assemblages in the local flora. Since A. euchroma and its associated assemblages
are linked to local livelihoods in Ladakh, yet quite vulnerable to climate change, the importance of our
results for future research and long-term monitoring in the Trans-Himalayan mountains is discussed.
... In fact, understanding vegetation dynamics of Alpine ecosystems can provide insight into future vegetation-climate feedback [61]. It would be beneficial to broader ecological and climatological implications, particularly in relation to the management of alpine ecosystems under climate change [62]. ...
Frost events during the growing season can significantly impact vegetation function and structure. Solar-induced chlorophyll fluorescence (SIF) and the normalized difference vegetation index (NDVI) are two widely used proxies for measuring vegetation growth. However, the extent to which NDVI and SIF respond to frost events and how the responses vary under different temperature, precipitation, and shortwave radiation conditions are still unclear. In this study, spatially gridded meteorological data were employed to identify frost events during the growing season in the Third Pole. Subsequently, vegetation responses to the frost events were examined using remotely sensed SIF and NDVI data in different seasons in the Third Pole. During the growing season, the number of frost events declined faster from 2001 to 2009 than from 2010 to 2018. From 2001 to 2009, most alpine vegetation areas in the Third Pole exhibited greening trends. SIF exhibited a strong correlation with environmental factors and showed higher sensitivity to environmental factors compared to the NDVI. Over the past two decades, the impact of temperature and frost days on alpine vegetation has decreased while the impact of precipitation and radiation has increased. This suggests that the control mechanisms governing alpine vegetation are gradually shifting in response to ongoing climate change in the Third Pole. This study enhances our comprehension of frost changes in alpine regions during the growing season and enriches our understanding of how alpine vegetation responds to climate change.
... According to recent studies, climatic warming has induced species range changes in alpine settings, including plant colonization at higher altitudes. Plant characteristics and regional ecological circumstances, which serve as filters by identifying species with characteristics suited for the conditions of the area, are the key factors influencing successful colonization at higher elevations (Hamid et al., 2020). For instance, the plant populations in the alpine Sikkim Himalaya have changed as a result of continuous warming. ...
Plant species, particularly those growing in mountains, are extremely susceptible to climatic alterations, as their distribution is predominantly determined by climatic factors. Changes in the climatic conditions influence the habitat suitability of plant species, and the species may adapt to it by changing their habitats in order to better match pre-existing climatic conditions. The Himalayan region, which symbolizes the greatest bioclimatic altitudinal gradient and provides the highest altitudinal boundaries for vascular plant species in the world, is extremely susceptible to climate change because of predominant topographic inclinations. In the region, suitable habitat areas of many plant species are dwindling due to warming and changes in precipitation regimes. It is anticipated that the currently suitable habitats of such species will become unsuitable and vice versa in the near future. Furthermore, many high-elevation plant species that are susceptible to high temperatures are relocating to higher altitudes. To comprehend the behavior of the species and make plans for the protection of biodiversity, it is imperative to monitor the distribution and habitat suitability of plant species with respect to climate change. For that purpose, the species distribution modeling (SDM) technique is quite helpful. This chapter explores the impact of climate change on the habitat suitability of plant species growing in the Himalayan region and the role of SDM in forecasting species’ response to climate change. Additionally, implications for the conservation and management of plant species in the region are discussed.
... Compositae, Poaceae, Ranunculaceae, Lamiaceae, and Rosaceae were recorded as dominant families due to their broader ecological amplitudes and adaptations to the harsh mountainous climate including dwarf size, stunted growth, herbaceous, and semi-woody vegetation (Brand et al., 2019;Zhang et al., 2015). Species diversity in high mountains across the globe is reported to generally decrease with increase in altitude (Hamid et al., 2020;Körner, 2007). However, contrastingly, results of Generalized linear model applied on B. utilis dominated vegetative communities revealed a rising tendency in species diversity and richness values with increasing altitude in the study area (Figs. 9, 10). ...
Betula utilis is the keystone tree species constituting the basic structure of the western Himalayan subalpine forests in Kashmir regions. It is endemic to Himalayan region, and performs dynamic ecological functions. Betula utilis populations in the region are threatened due to immense anthropogenic disturbances. There is little information available regarding the status of Betula populations in the region indicating acknowledge gap. This study investigated the distribution patterns, population structure, floristic diversity and phytosociological attributes of Betula forests, threats, as well as evaluating the habitat geography of the species using GIS analysis. Systematic quadrat-based sampling was used to record primary vegetation data and geographic attributes from a total of 30 subalpine forest sites in mountainous areas in an elevational range of 2800–3800 m. Betula utilis populations in the region were characterized with a stem density of 739.33 trees/ha with a basal area cover of 1974.93 m²/ha. The Betula papulations exhibited a regeneration potential of 609.33 seedlings/ha. A deforestation intensity of 351.33 Betula stumps/ha was recorded at the investigated sites. Floristic inventory revealed a total of 226 plant species recorded as associated flora in the Betula forest, belonging to 139 genera and 58 families. Communities exhibited moderate levels of diversity and richness having average values of Simpson's diversity index as 0.94; Shannon Wiener index as 3.22, species richness as 1.68, species evenness as 0.90, and community maturity index as 30.47. Biological spectrum analysis revealed Hemicryptophytes were the dominant life form whereas microphylls were the dominant leaf size class. ARC-GIS analysis significantly explained the habitat geography of the Betula populations. Digital elevation Model developed from SRTM dataset revealed that B. utilis populations were distributed in an altitudinal range of 2800–3800 m. North facing slopes with high degree of slope steepness were identified as the key habitats of the B. utilis populations. Fuelwood and timber extraction, and overgrazing were identified as major threats to the highly fragmented Betula populations in the region. Prevailing threats have significantly reduced B. utilis habitat, leading to a rapid decline in the species distribution range. It is recommended to formulate effective conservation measures such as community-based conservation initiatives, integrative sustainable harvesting policies, habitat restoration programmes, and promoting alternative livelihoods that support local communities to safeguard the Betula forests in the Himalayan region of Kashmir.
... It is crucial to monitor and understand these range shifts to assess their ecological implications and develop appropriate management strategies. It is quite plausible to speculate that climate change and other factors might have caused this upward shifting of cold-temperate and Mediterranean species (Hamid et al., 2020b). Recent studies indicate that the magnitude of these distributional shifts is even greater than initially anticipated (Taheri et al., 2021). ...
Range shifts are a key mechanism that species employ in response to climate change. Increasing global temperatures are driving species redistributions to cooler areas. Studies have documented climate change–induced shifts in species distributions. The range shift in three plant species, namely Bellis peren- nis L., Cannabis sativa L., and Portulaca oleracea L. to the Himalayan highlands of Ladakh, India, is reported for the first time. These species are not native to the region but have naturalized and are currently occurring as large natural populations at multiple sites. By providing detailed information on taxonomic descriptions, habitat characteristics, distribution maps, global distribution and ecology, the study aims to facilitate the identification of these species in the field which is required for early response and timely interventions to pre- vent them from becoming invasive in the natural habitats of the Himalayan region.
... The present study was conducted in Kashmir Himalaya, a mountainous region located on the western side of the Himalaya biodiversity hotspot (between 33.278 • N, and 75.342 • E, Fig. 1a). The region harbours an exceptionally rich endemic flora (Hamid et al., 2020b). The varied geomorphology of this region is known to have arisen as a result of the collision between Indian and Eurasian Plates (Ali et al., 2022). ...
In an era of global environmental change, the treeline shift triggered by recent climate warming has been reported worldwide. However, it is still unknown how site-specific microclimatic conditions regulate the soil-vegetation relationship at treelines, which constrains our capacity to down-scale broad global trends in the treeline shift at regional scale. In this study, we aimed to unravel fine-scale edaphic and vegetation patterns at two treeline sites in Kashmir Himalaya with in situ-measured microclimate using mini-loggers. At each site, we conducted sampling at the treeline leading edge, 100 and 300 m downslope and upslope. We employed boosted regression trees to find best predictors of the treeline vegetation among the microclimate and edaphic factors. We found intermediate microclimatic conditions at the leading edge but contrasting microclimates at the downslope and upslope. Our results demonstrate that the heterogeneity in microclimate driven by elevation strongly modulates the microsite edaphic conditions at the treelines, which in turn determines the fine-scale vegetation patterns. The soil temperature, moisture, pH, Cu, Zn, electrical conductivity and N were the best predictors of vegetation patterns at the treelines. The length of growing season measured at the treelines matched with the predicted values for the Himalaya, but growing season mean soil temperature of 7.31 – 8.15 °C recorded at the treelines is slightly higher than the postulated 6.4 °C global treeline isotherm. Our findings reveal that the soil microclimate strongly modulates edaphic and vegetation patterns at the treelines, thereby implying that even minor change in microclimate, like ongoing climate warming, can shift the current treeline position. However, this may be partially offset by the higher temperature isotherm in Kashmir Himalaya, thereby suggesting a slow-paced future treeline shift. Overall, the study advances our understanding about the crucial role of microclimate in determining soil-vegetation relationships at treelines with wide implications under ongoing and projected climate change.
... Although there are number of abiotic and biotic factors that determine species distribution ranges in mountain ecosystems, the climatic conditions particularly temperature and precipitation are the most important factors (Hamid et al. 2020). Being native to the Himalaya, Pinus wallichiana is distributed from Afghanistan, Pakistan, India, Nepal, Bhutan to China (Tibet, South-Central) and generally grows gregariously between 1800 − 3000 m in the temperate zone (Yadava et al. 2017). ...
... Like other parts of the Himalayan region, biodiversity of Kashmir Himalaya is also undergoing serious alterations owing to various drivers of biodiversity loss. Over the decades, many plant species have become threatened due to habitat loss, habitat fragmentation, deforestation, introduction of invasive species, overexploitation, overgrazing, land-use change, huge tourist influx, and building of roads, coupled with political disturbances , Hamid et al. 2020, Wani et al. 2022. Further, Kashmir Himalaya has experienced a significant influence of global climate change over the last few decades (Romshoo et al. 2015, Murtaza and Romshoo 2017, Romshoo et al. 2018 which is further disrupting the equilibrium in the natural ecosystems. ...
The present study attempts to comprehensively study the floristic elements of Gulmarg Wildlife Sanctuary (GWLS), Kashmir Himalaya. During the present study 364 species of vascular plants belonging to 227 genera and 74 families were recorded from the sanctuary. A total of 18 communities (10 within forest and 8 within alpine zone) were identified. Forest zone of the sanctuary was represented by shady moist, dry, bouldery, rocky, riverine and exposed habitats; whereas the alpine zone was represented by bouldery, riverine and moist and exposed habitats. Of the total 364 reported plant species, 161 species were native to Himalayan region and the remaining i.e. 203 species were non-natives. Out the total 161 native plant species, 82 were endemic to the Himalayan region. Further, 22 plant species were having threatened status in Jammu and Kashmir. Major threats to biodiversity within the sanctuary include over-exploitation, habitat degradation, overgrazing, invasive species, human settlements, huge tourism influx and pollution. In the present study, based on the 'conservation priority index' (CPI) of the plant species, 51 plant species were assessed to be threatened in GWLS. Further, maximum CPI of dry and shady moist habitats and Aesculus indica-Pinus wallichiana mixed and Taxus wallichiana-Prunus cornuta-Aesculus indica mixed communities reveals that proper management of these prioritized habitats and communities would help in maintaining the natural ecosystems and conservation of species of the sanctuary. Present study recommends that awareness about the values of biodiversity for sustenance through organization of training workshops, awareness camps need to be created among the local inhabitants as well as visitors. Further, no in-depth explorations for community characterization of forest and as well as alpine ecosystems of Kashmir Himalaya have been conducted; present study in the GWLS provides a template, which can be replicated in other protected as well as unprotected areas of the Kashmir Himalaya.
... Over the decades, many plant species have become threatened due to habitat loss, habitat fragmentation, deforestation, introduction of invasive species, overexploitation, overgrazing, land-use change, huge tourist influx, and building of roads, coupled with political disturbances (A. R. Dar, 2008;Khuroo et al., 2018;Tali et al., 2019;Hamid et al., 2020;S. A. Dar, Bhat, Aneaus, et al., 2020b, Mir et al., 2020. ...
The present study was carried out to assess the floristic diversity and community characteristics in the forest and alpine zone of Gulmarg Wildlife Sanctuary (GWLS), Kashmir Himalaya. A total of 123 sites were selected along an elevational gradient (2300–4200 m a.m.s.l) in each and every accessible aspect and habitats from July 2018 to June 2022. The present study recorded 364 species of vascular plants belonging to 227 genera and 74 families. Of the total species, 22 were trees, 34 shrubs, 290 herbs and 14 ferns. A total of 18 communities (10 within forest and 8 within alpine zone) were identified. Within the identified forest communities, species richness ranged from 44 to 198; tree density and total basal area ranged from 185–810 Ind ha−1 and 20.28–159.8 m2 ha−1, respectively. Density of shrubs and herbs in forest zone ranges from 886–2040 Ind ha−1 and 27.79–87.75 Ind m−2, respectively. Within the alpine communities, species richness ranged from 26–93; total density of shrubs and herbs ranged from 1410.0–5540 Ind ha−1 and 31.73–102.2 Ind m−2, respectively. Within the forest zone, diversity of trees, shrubs and herbs ranged from 0.88–1.67, 0.27–1.82 and 3.29–4.81, respectively. Within the alpine communities, species diversity of shrubs and herbs ranged from 0.73–1.33 and 2.21–3.69, respectively. Present study presents a first comprehensive floristic and community assessment of GWLS, and provides a template, which can be replicated in other protected as well as unprotected areas of the Kashmir Himalaya.
... Spasojevic et al., 2013;Swerhun et al., 2009) and Asia (e.g. Bhattarai et al., 2021;Hamid et al., 2020;Liu et al., 2018;Sigdel et al., 2018;Zhou et al., 2019), with few in South America (e.g. Bokhorst et al., 2017;Duchicela et al., 2021;Pelayo et al., 2021), Africa (Carbutt & Thompson, 2021), or Oceania (e.g. ...
Alpine ecosystems occur above the bioclimatic treeline and support cryophilic plant communities with high endemism, which are governed by low temperatures and short growing seasons. However, the climate of many alpine ecosystems is changing rapidly with warming temperatures, declining snow cover and lengthening growing seasons. Alpine vegetation dynamics in response to changes in climate over recent decades have been observed via long-term ecological monitoring techniques, but such studies are less common in the southern hemisphere including in the marginal alpine ecosystems of the Australian Alps. Therefore, the scale, ecological processes and implications of climate-induced dynamics are less clear for this important ecological, cultural and socioeconomic region. The central aim of this thesis is to understand the responses of vegetation in the largest contiguous alpine area in the Australian Alps, the Kosciuszko alpine area, to climate change over recent decades across varying spatial scales.
To assess the status, distribution, themes and evolution of research examining alpine vegetation in relation to climate change, a multi-component bibliometric literature review was conducted (Chapter 2). Globally, there were 3,143 publications relating to climate change and alpine vegetation, with research on this topic exceeding the rate of increase apparent for research in general, which likely reflects the pronounced changes observed recently in alpine ecosystems. However, geographic disparities were apparent when continental alpine areas were compared with research outputs. Temporally, there was a shift in research from treelines to grasslands, largely driven by increasing research about the Tibetan Plateau, but there are still relatively few studies on cryophilic and periglacial communities. Traditional, field-based ecological monitoring techniques were often used, but increasingly remote sensing techniques are providing valuable insights. The review highlights the importance of this topic, changes in methods and technology, and important thematic and geographic research gaps including relatively limited research in the southern hemisphere.
Beginning at the microscale (metres), microclimate and vegetation dynamics along snowmelt gradients over 13 years were assessed in critically endangered snowpatch communities in the Kosciuszko alpine area (Chapter 3). Specifically, snowmelt zones were delineated using continuous soil temperature monitoring while vegetation composition was assessed using data from of 84 permanently-marked 1 m2 quadrats surveyed in 2007 and 2013, combined with new data from a survey in 2020 conducted as part of this thesis. Microclimatic changes were most pronounced in the late melt zone, where growing seasons have lengthened and temperatures have warmed, with the initially distinct microclimates of each melt zone becoming more similar over time. Alongside these microclimatic changes, there was increasing cover of graminoids and declining cover of snowpatch specialists in the mid and late melt zones, but diversity remained relatively stable across the three surveys. There were changes in composition as well as community-weighted traits and strategies, with vegetation increasingly dominated by taller species with larger leaves resulting in a shift from ruderal-tolerant to stress-tolerant compositions over time. With the climate continuing to warm, the loss of defining abiotic and biotic characteristics of snowpatches may lead to ecosystem collapse via replacement by a novel ecosystem.
Moving up to mesoscale dynamics (hectares), microclimate and vegetation dynamics of common alpine plant communities were assessed over 15 years along an elevation gradient in the Kosciuszko alpine area (Chapter 4). Specifically, microclimatic data were obtained from continuous soil temperature monitoring. Vegetation composition data were obtained from permanently-marked plots on five ~ 1 ha summits surveyed in 2004 and 2011, along with new data from a survey in 2019 conducted as part of this thesis. At this mesoscale, soil temperatures increased through time and were correlated to air temperatures. While species richness increased over time, diversity declined as a result of biotic homogenisation driven by the increasing cover of generalist and thermophilic graminoids and shrubs via densification and in-filling. There were also elevation-dependant changes in cover and composition with increasing dominance of shrubs at lower elevations and graminoids at higher elevations, with the most pronounced changes in composition at higher elevations. As climate-induced vegetation dynamics intensify with further warming, there are important implications for increasing potential for novel biotic interactions along elevation gradients as well as increasing biomass and landscape flammability in this alpine area.
Finally, to understand macroscale (kilometres) and longer-term dynamics over three decades in response to climate change and the landscape-level wildfires in 2003, changes across the whole Kosciuszko alpine area (~455 km2) were assessed (Chapter 5). Changes in climate were identified including increasing temperatures (1910-2019), precipitation (1900-2019) becoming more seasonally variable and declining snow cover (1954-2021), with the most rapid changes in recent decades. Then, vegetation cover and zonation were modelled using optimised random forest classification of Landsat growing season composites for 1990, 2000, 2010 & 2020. Concurrent with recent changes in climate, the cover of woodlands has increased via densification at lower elevations but there has been treeline stasis, except where wildfires resulted in treeline recession. Heathlands were mostly replaced by woodlands at lower elevations and shrublines have advanced upslope, however wildfire led to suppression of upslope movement in burnt areas as grasslands replaced burnt heathlands at higher elevations. Small increases in the cover of screelands were associated with drought and loss of vegetation during the less extensive 2020 wildfires. Finally, wildfire led to increasing cover of grasslands, which recovered rapidly in areas burnt in 2003 but were replaced by heathlands and woodlands by 2020. With increasing landscape flammability and fire weather conditions associated with climate change in this alpine area, some vegetation dynamics may be incremental in response to relatively gradual climatic changes while others may be transformative in response to wildfires.
Overall, this thesis provides novel insights and addresses important knowledge gaps regarding how alpine vegetation responds to climate change, particularly in the Australian Alps. Specifically, the climate has changed rapidly over recent decades with warmer temperatures, lengthening growing seasons, more variable precipitation and declining snow cover, all of which are abiotic determinants of alpine vegetation. In response, there has been increasing cover of generalist and thermophilic competitive taxa and subsequent declines in cryophilic taxa. Climate-induced responses may be amplified along elevation and snowmelt gradients, with fire regulating woody advances upslope but not encroachment via densification at lower elevations. With the cumulative loss of abiotic and biotic factors conditions that governed the distribution of alpine vegetation in the past, as well as the increasing risk of wildfire, the stability and persistence of the Kosciuszko alpine flora is in question. Without effective climate action alongside the mitigation of threats such as invasive species, wildfire and recreation impacts, further vegetation dynamics changes seem imminent.
... More than two decades ago, the GLORIA network initiated a global effort for monitoring the impact of climate change on plant diversity in mountain summits through a worldwide long-term observation network (Pauli et al. 2015). With its multi-summit approach along elevation gradients, this methodology captures an important proportion of the plant species and functional diversity in each target region, quantifying spatiotemporal changes in plant abundance and composition, together with temperature data (Gottfried et al. 2012;Hamid et al. 2020). ...
Tropical alpine ecosystems exhibit outstanding plant diversity and endemism while
being particularly sensitive to the impacts of climate change. Although understanding spatiotemporal changes in plant species composition, richness and community structure along tropical alpine altitudinal gradients is of primary importance, both the functional and historical/biogeographic dimensions of vegetation diversity remain largely unexplored. We used Generalized Linear Models and multivariate analyses to assess changes in species, growth forms, and biogeographic groups richness and abundance, in response to habitat variables along an elevation gradient in seven summits (3800 to 4600 m asl) in the Venezuelan Andes, studied using the standardized approach of the GLORIA-Andes monitoring network. The habitat variables assessed were soil temperature (-10 cm), soil organic matter, slope inclination, and substrate cover. We found 113 species, representing 72 genera, 32 families, 13 growth forms, and seven biogeographic origins, that included 25% of endemic elements. We observed richer vegetation, both in terms of species and growth forms, in summits with higher soil temperatures and higher SOM content, as well as higher biogeographic origin richness with increasing soil temperatures. The presence of holarctic elements increased toward higher elevations, while the occurrence of austral antarctic elements increased toward lower elevations. Our results indicate that biogeographic and functional approaches to vegetation diversity capture well the effect of abiotic filtering on community structuring in these tropical alpine environments. These findings constitute an important baseline for monitoring vegetation dynamics linked to climate change in the Venezuelan Andes by highlighting the functional and historical perspective on vegetation analyses, in contrast with more traditional approaches, based only on taxonomic species diversity.
... Although there are number of abiotic and biotic factors that determine species distribution ranges in mountain ecosystems, the climatic conditions particularly temperature and precipitation are the most important factors (Hamid et al. 2020). Being native to the Himalaya, Pinus wallichiana is distributed from Afghanistan, Pakistan, India, Nepal, Bhutan to China (Tibet, South-Central) and generally grows gregariously between 1800 − 3000 m in the temperate zone (Yadava et al. 2017). ...
Documenting distribution records of biodiversity at regional scale plays a pivotal role in bridging the Wallacean shortfall in global knowledge on biodiversity. Here we report the first distribution record of a tree species, Pinus wallichiana A. B. Jackson to the flora of Ladakh – a remote region in Indian Trans-Himalaya. The tree species grows wild in the interior mountain valley of Kaksar in district Kargil of the region. Taxonomic description and photographic illustrations of the species are provided here to facilitate easy identification. We also highlight the scientific significance of this new tree species record in better understanding of biogeography, paleoecology and paleo-climate of this remote Trans-Himalayan region in India.
... We used the thermophilization and moistphilization indicator to quantify the effect of climate change on the composition of alpine vegetation. Those indicators were derived from previous studies 2, 14,15 . First, the vegetation thermic and moist indicators of each summit section and survey were calculated as the community-weighted mean of the species niche that was weighed by species cover. ...
Climate change has caused severe impacts on ecosystems and biodiversity globally, especially to vulnerable mountain ecosystems; the summits bear the brunt of such effects. Therefore, six summits in Taiwan were monitored based on a standardized multi-summit approach. We used both statistical downscaling of climate data and vegetation cover data to calculate climate niches to assess the impacts of climate change. Two indicators, thermophilic and moist-philic, were applied to evaluate the overall response of vegetation dynamics. The results revealed that potential evapotranspiration increased significantly and led to a declining tendency in monthly water balance from 2014 to 2019. The general pattern of species richness was a decline. The difference in plant cover among the three surveys showed an inconsistent pattern, although some dominant species expanded, such as the dwarf bamboo Yushania niitakayamensis. The thermophilic indicator showed that species composition had changed so that there were more thermophilic species at the three lowest summits. The moist-philization indicator showed a decline of humid-preferred species in the latest monitoring period. Although total precipitation did not decrease, our results suggest that the variability in precipitation with increased temperature and potential evapotranspiration altered alpine vegetation composition and could endanger vulnerable species in the future.
... The meteorological satellite will play a significant role in ensuring the construction quality. [13] In a word, cooperation with countries along the Belt and Road to address climate change fully embodies the purposes of the UN 2030 agenda for sustainable development and the Paris Agreement on climate change. All Countries should seize the opportunities brought about by joint cooperation to achieve mutual benefit and win-win results. ...
The Belt and Road is the abbreviation of the Silk Road Economic Belt and the 21st Century Maritime Silk Road. The countries along the Belt and Road routes are generally highly sensitive and vulnerable to climate change, so it is urgent to design a service platform for climate change prediction and monitoring. In this paper, based on the various demands of climate change prediction and monitoring, we analyzed the importance of the establishment of a climate service platform and the main measures to improve the capabilities of climate service platform. According to the principle of “refinement, systematization and specialization”, a meteorological service platform was designed, which are based on space remote sensing, supplemented by airborne remote sensing, and verified by the ground observation network to verify that the real-time monitoring and prediction of sky and ground integration. The platform can provide scientific basis for the countries along the routes, and improve the infrastructure construction progress and personnel safety along the Belt and Road.
In the present era of accelerating climate change, a comprehensive understanding of the distribution patterns of plant communities and their driving factors is pivotal in ecological studies. In view of this, the present research assessed species diversity and composition patterns in the alpine region of Uttarakhand, west Himalaya and their relation with the environmental conditions (climatic, edaphic and topographic) using the standard protocol of Global Observation Research Initiative in Alpine Environment. A total of 104 vascular plants (71 genera and 35 families) were documented in the study with Asteraceae (16 species in 14 genera) being the dominant family. The diversity indices across the study area exhibited significant variations (p < 0.05) with respect to altitude and aspect, i.e., richness and diversity values were higher in lower altitude summits and in south- and east-facing mountain slopes. β-diversity partitioning indicated that there was higher compositional heterogeneity with respect to altitude than aspects, where variation in composition was observed only in case of habitat heterogeneity. Based on the magnitude and representation of the selected climatic and edaphic factors across all plots, distinct clusters of summit sites were formed by principal component analysis that exhibited significant changes in environmental conditions with respect to altitude rather than aspects. Canonical correspondence analysis revealed a strong relationship of community composition with environmental factors, with soil temperature, moisture, organic carbon and nitrogen content prominent edaphic factors and annual air temperature, temperature seasonality, solar radiation and isothermality prominent climatic factors influencing the community compositions. The present study, therefore, enhances our understanding of the contribution of potential drivers that determine spatial patterns of plant diversity on mountain summits, which help monitor, model and predict how the mountain ecosystems will respond to climate warming in the Himalaya.
Recent climate research has revealed that climate change will impact biodiversity, particularly in mountainous regions. Furthermore, species that are endemic and rare will be more significantly impacted. Codonopsis affinis (Campanulaceae) is a rare and endemic twiner in the Darjeeling eastern Himalaya. The present study is focused on species distribution modeling of C. affinis using the MaxEnt algorithm. Models were generated by first collecting occurrence points within the study area, followed by model generation. The modeling throws light on the current and future distribution and range shift of the species with respect to climate change. Modeling was performed with six occurrence points and nine uncorrelated bioclimatic and topographic variables. All the generated models performed well, with AUC value of 0.992, and TSS value of 0.904. The main variable that impacts the species distribution happens to be altitude. The current habitat area is 274.5 sq km after applying the 0.61 minimum training presence threshold. Overall, a sharp decline in the probable suitable habitat is observed in the future models compared to the current one, reducing from 8.83% of the total habitat to about 0 to 1.35% in the future. This indicates that future climate change could negatively impact this endemic species. Furthermore, the taxon is also impacted by other anthropogenic factors, such as changes in land use. This implies urgency for prioritizing this neglected species, and hence, it would be ideal to take measures to conserve this rare species either through ex-situ or in-situ approaches.
Globally, rapid climate and land-use changes in alpine environments are posing severe risks to their bountiful biodiversity and ecosystem services. Currently, nature-based solutions are fast-emerging as the preferred approach to address the challenges of environmental sustainability. In alpine environments, cushion plants owing to their unique architecture and adaptability offer a potential nature-based system to plan biodiversity conservation and habitat restoration strategies. Here, we employed an analytical framework to test whether and how the cushion plants facilitate the sustenance of alpine plant diversity in Kashmir Himalaya. We specifically aimed to answer: what are the effects of the cushion plants on the patterns of alpine species richness and phylogenetic diversity, and whether these effects vary across spatial scales (local versus landscape), cushion types, and changing elevation. We randomly selected pairs of cushion and neighbouring non-cushion plots (size 100 m2) across 34 different alpine sites in the study region. Within each plot, we randomly laid three 5 m2 quadrats for vegetation sampling, and sampled a total of 204 quadrats in 68 plots with seven cushion types along elevation ranging from 3100 to 3850 m. Our results revealed positive effects of the cushions by supporting a higher community species richness (SR) and phylogenetic diversity (PD). The effects were consistent both at the local (i.e., quadrat) and landscape (i.e., plot) scales, but varied significantly with the cushion type. Interestingly, SR and PD showed an increasing trend with increase in elevation in cushion communities, thereby supporting stress gradient hypothesis. Along the elevational gradient, the cushion communities showed phylogenetic overdispersion, but clustering by non-cushions. Overall, our study provides empirical evidence to reinforce the role of the cushions as conservation refugia for an imperilled alpine plant diversity in the Himalaya. Looking ahead, we highlight the far-reaching implications of our findings in guiding the nature-based environmental management of alpine ecosystems worldwide.
Symphyotrichum subulatum (Michx.) G.L.Nesom (Asteraceae) is reported as a new alien plant record for Kashmir Himalaya. The taxonomic identification of species is confirmed on the basis of shape of involucre, floral and seed characters. Detailed description, distribution map, and comments on distribution and ecology are also provided along with photographic illustration to facilitate easy identification of this species.
Invasive alien species are currently considered as one of the dominant drivers of global environmental change. Till now, the majority of studies have focused on single or a few traits of alien species that facilitate their invasion. Also inclusion of all the traits which determine the transition of aliens along the different stages of invasion continuum (casual, naturalised and invasive) has remained largely overlooked. In this study, we collected a comprehensive trait dataset on 144 alien plant species of Kashmir Himalaya – a global biodiversity hotspot region. To test which traits of alien species, individually or in combination along with anthropogenic factors, determine their transition along the invasion continuum, we employed chi-square tests, boosted regression trees and phylogenetic methods. We found the perennial lifespan, longer residence time, greater number of introduced regions, and better seed dispersal mechanism were critical in determining the transition from casual to naturalised. The herbaceous growthform (therophytes), annual lifespan, achene fruit, longer residence time and broader introduced range were the species’ traits determining transition from naturalised to invasive. Aliens introduced as ornamentals have more propensity to become naturalised; whereas aliens introduced unintentionally show overrepresentation at the invasive stage. Phylogeny alone showed mixed results indicating both clustering and dispersion; however in combination with other traits, it plays a significant role in determining the stage of invasion. Overall, our results disentangle the individual and interactive roles of multiple traits that determine the transition of alien species’ along the invasion continuum. Further, we foresee the potential applicability of our findings in designing robust invasion risk analysis protocols and stage-specific invasion management strategies in this Himalayan region, with learnings for elsewhere in the world.
Treeline ecotone, though studied the world over because of its sensitivity to changing climate, has received limited attention in the Himalaya. It is in this backdrop that an extensive study in the Daksum-Sinthan Top area of Kashmir Himalaya, India, was carried out to document the taxonomic, life-form and phylogenetic diversity of plant assemblages at the treeline ecotone in relation to elevation and aspect. A total of 235 species belonging to 168 genera and 71 families were recorded in the ecotone. Only 26% of species were common between the north-facing and south-facing aspects, and a decline in the total number of species with elevation was the general trend. Herbs were predominant at all the elevations on both aspects. Sørensen’s dissimilarity across the elevations and aspects was low and the turnover component (βsim) was the major contributor to the overall dissimilarity. Phylogenetic overdispersion was noticed at lower elevations and phylogenetic clustering was prevalent at higher elevations on both aspects. Diffuse-type treeline-form was more common on the north-facing slope and tree-island type on the south-facing slope. The dominant treeline species on the north-facing slope was Betula utilis, and Pinus wallichiana on the south-facing slope.
Elevational gradient, slope, and aspect offer a unique opportunity to explore the response of plant species under changing environmental conditions. The present study aimed to analyze the species diversity and distribution patterns with respect to altitude, aspect, and habitat types in the Kashmir Himalayas. Considering major aspects and habitats, a total of 123 representative sites were selected along the elevational gradients for the present study. The plant species composition of each selected site was studied by organized sampling following the standard ecological methods. During the present study, a total of 361 vascular plant species belonging to 71 families and 214 genera were identified in the study area. At the lower altitudes, the southern aspect and drier habitats showed the highest diversity. Moreover, a significant amount of compositional dissimilarity was observed between the studied aspects, habitats, and elevation belts and was mainly due to species turnover rather than the nestedness component. Further, among the studied variables, altitude was the most important contributing variable, explaining the greatest variation in the species composition. The paired effects of altitude and habitat explained the maximum variation in plant species composition. It may be concluded that floristic diversity should be studied not only with reference to elevational gradients but should also include aspects and habitats. The current study will act as a reference in this direction. A similar study must be replicated in other parts of the Himalayan region in the future to improve our understanding of the distribution and preferences of plant species in mountainous zones. This, in turn, will be immensely helpful in the conservation and sustainable utilization of resources in these ecologically fragile regions.
Elevational gradient, slope, and aspect offer a unique opportunity to explore the response of plant species under changing environmental conditions. The present study aimed to analyze the species diversity and distribution patterns with respect to altitude, aspect, and habitat types in the Kashmir Himalayas. Considering major aspects and habitats, a total of 123 representative sites were selected along the elevational gradients for the present study. The plant species composition of each selected site was studied by organized sampling following the standard ecological methods. During the present study, a total of 361 vascular plant species belonging to 71 families and 214 genera were identified in the study area. At the lower altitudes, the southern aspect and drier habitats showed the highest diversity. Moreover, a significant amount of compositional dissimilarity was observed between the studied aspects, habitats, and elevation belts and was mainly due to species turnover rather than the nestedness component. Further, among the studied variables, altitude was the most important contributing variable, explaining the greatest variation in the species composition. The paired effects of altitude and habitat explained the maximum variation in plant species composition. It may be concluded that floristic diversity should be studied not only with reference to elevational gradients but should also include aspects and habitats. The current study will act as a reference in this direction. A similar study must be replicated in other parts of the Himalayan region in the future to improve our understanding of the distribution and preferences of plant species in mountainous zones. This, in turn, will be immensely helpful in the conservation and sustainable utilization of resources in these ecologically fragile regions.
Elevational gradient, slope, and aspect offer a unique opportunity to explore the response of plant species under changing environmental conditions. The present study aimed to analyze the species diversity and distribution patterns with respect to altitude, aspect, and habitat types in the Kashmir Himalayas. Considering major aspects and habitats, a total of 123 representative sites were selected along the elevational gradients for the present study. The plant species composition of each selected site was studied by organized sampling following the standard ecological methods. During the present study, a total of 361 vascular plant species belonging to 71 families and 214 genera were identified in the study area. At the lower altitudes, the southern aspect and drier habitats showed the highest diversity. Moreover, a significant amount of compositional dissimilarity was observed between the studied aspects, habitats, and elevation belts and was mainly due to species turnover rather than the nestedness component. Further, among the studied variables, altitude was the most important contributing variable, explaining the greatest variation in the species composition. The paired effects of altitude and habitat explained the maximum variation in plant species composition. It may be concluded that floristic diversity should be studied not only with reference to elevational gradients but should also include aspects and habitats. The current study will act as a reference in this direction. A similar study must be replicated in other parts of the Himalayan region in the future to improve our understanding of the distribution and preferences of plant species in mountainous zones. This, in turn, will be immensely helpful in the conservation and sustainable utilization of resources in these ecologically fragile regions.
Treeline ecotones, the transition zone between the upper closed forest limit (timberline) and treeless alpine vegetation, are the most conspicuous features of mountain ecosystems around the world. Understanding the patterns of plant species richness in the treeline ecotones is crucial in accurately assessing and monitoring the treeline shifts and vegetation dynamics in the face of climate warming. The present chapter, based on a quantitative systematic review of the scientific literature published over the last 30 years (1991 to 2021), unravels the taxonomic and distributional patterns of plant species richness in the Himalayan treeline ecotone. We found a total of 593 vascular plant species belonging to 232 genera in 70 families reported in the literature on treeline ecotones of the Himalaya. Asteraceae, Rosaceae, Ericaceae, Ranunculaceae, and Pinaceae were found to be species-rich families. Overall, the treeline ecotone plant species pool was higher in Western Himalaya as compared to that of Eastern Himalaya and only a small proportion of species was common to both the regions. The majority of the species were of herbaceous growth form and the trend was consistent across the treeline ecotones of Western and Eastern Himalaya. In the ecotone flora of the Himalaya, there are 2 plant species currently recognised by IUCN as Near Threatened, 4 Vulnerable, 7 Endangered, and 2 as Critically Endangered. Based on the insights gained from the present empirical synthesis, we highlight the research knowledge gaps and suggest way forward for better understanding of patterns of treeline ecotone flora in the Himalaya.
In an era of climate change, quantifying forest biomass and carbon stock along elevational gradients in moun- tainous areas assumes immediate relevance for carbon budgeting and forest management. Here, we carried out extensive field studies to quantify the tree biomass and carbon stock of major forest types along a wide eleva- tional gradient (350–3450 m) in Jammu and Kashmir, a region located in the northwestern Himalaya. We adopted a stratified random cluster sampling approach to generate ground-based data on structural variables (diameter at breast height-DBH, stem height, basal area, stem density, species richness), and quantified biomass and carbon stock volume using allometric equations in 12 major forest types in the region. We found a significant difference in all the tree structural variables among the forest types. Our results show a significantly positive correlation between DBH and height, but a significantly negative correlation of stem density with DBH and height. We observed a higher basal area in the forest types between 1750 and 3350 m elevation, with the highest value (104.4 ± 29.0) found in Fir forest. We also found higher stem density values at mid- and high-elevations in comparison to low-elevation, but the trend was inconsistent. To evaluate the influence of elevation on the structural attributes, we fitted a Linear Regression Model (LM) for each variable, followed by F-test. We observed a significant effect (p < 0.008) of elevation on all the forest tree structural variables, species richness, biomass and carbon stock. All these variables, except species richness, showed a positive relationship with elevation. We found the highest aboveground-, belowground-, total biomass, and carbon stock in the forest types at high elevation above 1750 m. The most significant tree species in terms of biomass and carbon stock contribution was Abies pindrow, followed by Cedrus deodara and Pinus roxburghii, thus making them suitable tree species for forest conservation and restoration in this Himalayan region. Principal component analysis of anthropogenic distur- bances revealed the fire mostly associated with the forest types dominated by P. roxburghii, stem cutting with those dominated by C. deodara, P. wallichiana and A. pindrow, and grazing with the high-elevation forest types. Overall, our study unravels the patterns of forest carbon stock along a wide elevational gradient in this Hima- layan region, with immediate implications for climate change mitigation policy and practice in mountainous landscapes.
In an era of climate change, quantifying forest biomass and patterns of carbon stock along elevational gradients in mountainous areas are particularly important for carbon budgeting and forest management. Here, we carried out extensive field studies to quantify the tree biomass and carbon stock of 12 major forest types along a wide elevational gradient (350-3450 m) in Jammu and Kashmir, a region located in the northwestern Himalaya. We adopted a stratified random cluster sampling approach to generate ground-based data on structural variables (diameter at breast height-DBH, stem height, basal area, stem density, species richness), and quantified biomass and carbon stock volume using allometric equations in the major forest types in the region. We found a significant difference in all the tree structural variables among the forest types. Our results show a positive and significant correlation between DBH and height, but a negative and significant correlation of stem density with DBH and height. We observed a higher basal area between 1750 and 3350m elevation belt, with the highest value (104.4±29.0) found in Fir forest. We found higher stem density values at mid- and high-elevations in comparison to low-elevation, but the trend was inconsistent. To evaluate the influence of elevation on the structural attributes, we fitted a Linear Regression Model (LM) for each variable, followed by F-test. We observed a significant effect (p< 0.008) of elevation on all the forest tree structural variables, species richness, biomass and carbon stock. All these variables, except species richness, showed a positive relationship with elevation. We found the highest aboveground-, belowground-, total biomass, and carbon stock in the forest types at high elevation above 1750 m. The most significant tree species in terms of biomass and carbon stock contribution was Abies pindrow, followed by Cedrus deodara and Pinus roxburghii, thus making them suitable tree species for forest conservation and restoration in this Himalayan region. Principal component analysis of anthropogenic disturbances revealed the fire mostly associated with the forest types dominated by P. roxburghii, stem cutting with those dominated by C. deodara, P. wallichiana and A. pindrow, and grazing with the high-elevation forest types. Overall, our study unravels the patterns of forest carbon stock along a wide elevational gradient in this Himalayan region, with immediate implications for climate change mitigation policy and practice in mountainous landscapes.
Several anthropogenic activities can impact forest carbon (C) dynamics. In the Himalaya, insufficient studies are available on the intensity and impacts of multiple anthropogenic activities on forest C stocks. Here, we studied the changes in tree C stock in temperate forest stands of Kashmir Himalaya due to anthropogenic disturbances. We sampled forest sites with High-Disturbance (HD) and Low-Disturbance (LD) by randomly generating points in Arc GIS 10.1. A total of 24 square plots (0.1 ha size), comprising 12 in each disturbance level, were laid for the estimation of tree C stock. The tree cutting and the mean basal area of cut stems per hectare was greater in HD sites as compared to LD sites. The rapid rate of tree cutting was indicated by a low stem/stump ratio of 1.7 on HD sites. At LD sites, the live trees contributed more to the C stock (94%) than in HD sites (80%). The intensity of tree cutting was far higher near human settlements, contributing with 28.9 Mgha−1 of carbon loss at the HD sites. Our results reveal that the cumulative impacts of anthropogenic disturbances, especially near human settlements where road connectivity and ease of access lead to faster logging, may change the forest structure and C stock potential in the temperate forests of Kashmir Himalaya. Our findings have direct implications for the climate-smart forestry and forest restoration in the region.
Symphyotrichum subulatum (Michx.) G.L.Nesom (Asteraceae) is reported as a new alien plant record for Kashmir Himalaya. The taxonomic identification of species is confirmed on the basis of shape of involucre, floral and seed characters. Detailed description, distribution map, and comments on distribution and ecology are also provided along with photographic illustration to facilitate easy identification of this species. Citation: Gulzar R, Khuroo AA, Rather ZA, Ahmad R, Rashid I (2021) Symphyotrichum subulatum (Michx.) G.L.Nesom (Asteraceae): a new distribution record of an alien plant species in Kashmir Himalaya, India. Check List 17 (2): 569-574. https://doi.
Aim: Variation in diversity is a well-documented spatial pattern in biogeography, but an overarching climate-based theory of diversity is lacking. We evaluate two models of species richness related to species-richness-energy theory. One is based on net primary production (NPP) or the more individuals hypothesis (MiH), and the other is a model based on water-energy dynamics (WED). We use taxa from three kingdoms along an extensive elevation-temperature gradient. Both WED and NPP-MiH are based on thermal energy, but the question is whether energy operates through regulating production and chemical (potential) energy only (NPP-MiH), or if kinetic energy as regulator of available liquid water is needed (WED). Location: Central Himalayas. Methods: The biodiversity, that is, elevational gamma diversity, of 12 taxa containing animals, plants, and fungi was estimated from range data along an elevation gradient. Generalized linear models were fitted to the species richness data, and the Akaike information criterion (AIC) and deviance explained were used to evaluate the NPP-MiH and WED models. In addition, we tested the relationships with precipitation and length of growing season (LGS) and their interaction. Results: The peaks in richness of the taxa are dispersed along the entire Himalayan bioclimatic gradient from the subtropics to the alpine zone. WED performs best for all taxa along the entire gradient. In the non-tropical zone, NPP-MiH is best for reptiles , and NPP-MiH and WED are equally good for mammals and amphibians. Including the length of the growing season in the WED model improves the AIC for eight taxa, and WED is superior for combined cross-taxon biodiversity along the entire gradient, but WED and NPP-MiH are equally good in the non-tropical zone. Conclusion: Water-energy dynamics is able to predict peaks in species richness under different climate and primary production conditions; hence, WED is better and more general than NPP-MiH. The interaction with precipitation and the length of the growing season, which also reflects primary production, improve the model for several organism groups. Hence, LGS may improve and unify future mechanistic first-principle model of biodiversity. K E Y W O R D S elevational gamma diversity, elevation-temperature, gradient, length of growing season, more individuals hypothesis, net primary production, species richness, water-energy dynamics Editor: Dr. Jenny McGuire
Agriculture and the exploitation of natural resources have transformed tropical mountain ecosystems across the world, and the consequences of these transformations for biodiversity and ecosystem functioning are largely unknown1–3. Conclusions that are derived from studies in non-mountainous areas are not suitable for predicting the effects of land-use changes on tropical mountains because the climatic environment rapidly changes with elevation, which may mitigate or amplify the effects of land use4,5. It is of key importance to understand how the interplay of climate and land use constrains biodiversity and ecosystem functions to determine the consequences of global change for mountain ecosystems. Here we show that the interacting effects of climate and land use reshape elevational trends in biodiversity and ecosystem functions on Africa’s largest mountain, Mount Kilimanjaro (Tanzania). We find that increasing land-use intensity causes larger losses of plant and animal species richness in the arid lowlands than in humid submontane and montane zones. Increases in land-use intensity are associated with significant changes in the composition of plant, animal and microorganism communities; stronger modifications of plant and animal communities occur in arid and humid ecosystems, respectively. Temperature, precipitation and land use jointly modulate soil properties, nutrient turnover, greenhouse gas emissions, plant biomass and productivity, as well as animal interactions. Our data suggest that the response of ecosystem functions to land-use intensity depends strongly on climate; more-severe changes in ecosystem functioning occur in the arid lowlands and the cold montane zone. Interactions between climate and land use explained—on average—54% of the variation in species richness, species composition and ecosystem functions, whereas only 30% of variation was related to single drivers. Our study reveals that climate can modulate the effects of land use on biodiversity and ecosystem functioning, and points to a lowered resistance of ecosystems in climatically challenging environments to ongoing land-use changes in tropical mountainous regions.
Environmental gradients are caused by gradual changes in abiotic factors, which affect species abundances and distributions, and are important for the spatial distribution of biodiversity. One prominent environmental gradient is the altitude gradient. Understanding ecological processes associated with altitude gradients may help us to understand the possible effects climate change could have on species communities. We quantified vegetation cover, species richness, species evenness, beta diversity, and spatial patterns of community structure of vascular plants along altitude gradients in a subarctic mountain tundra in northern Sweden. Vascular plant cover and plant species richness showed unimodal relationships with altitude. However, species evenness did not change with altitude, suggesting that no individual species became dominant when species richness declined. Beta diversity also showed a unimodal relationship with altitude, but only for an intermediate spatial scale of 1 km. A lack of relationships with altitude for either patch or landscape scales suggests that any altitude effects on plant spatial heterogeneity occurred on scales larger than individual patches but were not effective across the whole landscape. We observed both nested and modular patterns of community structures, but only the modular patterns corresponded with altitude. Our observations point to biotic regulations of plant communities at high altitudes, but we found both scale dependencies and inconsistent magnitude of the effects of altitude on different diversity components. We urge for further studies evaluating how different factors influence plant communities in high altitude and high latitude environments, as well as studies identifying scale and context dependencies in any such influences.
Background: Inselberg summits adjacent to the Maloti–Drakensberg escarpment occupy an alpine zone within the Drakensberg Alpine Centre (DAC). Inselbergs, the escarpment and surrounding mountains such as Platberg experience a severe climate; inselberg summits are distinct by being protected from human disturbance.
Objectives: The aim of this article was to describe for the first time the flora of inselberg summits and to assess their potential contribution to conservation of DAC plant diversity.
Method: We investigated whether the flora of inselberg summits formed a representative subset of the DAC flora in terms of shared, especially endemic or near endemic, species and representation of families. All species were listed for six inselbergs between Giant’s Castle and Sentinel, located in the Royal Natal National Park (RNNP) during November 2005. Comparisons, using literature, were made with floras of the DAC, as well as Platberg, an inselberg approximately 60 km north from Sentinel in the RNNP.
Results: We recorded 200 species of pteridophytes and angiosperms on inselbergs, 114 DAC endemics or near endemics, one possible new species, and several range and altitudinal extensions. Asteraceae, Poaceae and Ericaceae comprised 42.1% of endemic and near endemic species, with Scrophulariaceae and Hyacinthaceae contributing 8.8%. Inselberg and DAC floras differed in respective rankings of Crassulaceae (8th vs. > 15th), Polygalaceae, Apiaceae and Rosaceae (10th, 11th, 12th vs. > 15th), Poaceae (2nd vs. 5th), Cyperaceae (3rd vs. 4th) and Scrophulariaceae (6th vs. 2nd). Growth forms on inselbergs were consistent with DAC flora. Inselbergs shared 40% of species with Platberg.
Conclusion: Inselbergs, which supported 7.9% of species occurring in the DAC flora, are well protected from human impact, lack alien plants, but, despite this, are highly vulnerable to climate change. Conservation importance of inselbergs will increase as escarpment vegetation becomes increasingly degraded as a consequence of intensifying land use.
Protected areas (PAs) play a critical role in conserving biodiversity and maintaining viable populations of threatened species. Yet, as global change could reduce the future effectiveness of existing PAs in covering high species richness, updating the boundaries of existing PAs or creating new ones might become necessary to uphold conservation goals. Modelling tools are increasingly used by policymakers to support the spatial prioritization of biodiversity conservation, enabling the inclusion of scenarios of environmental changes to achieve specific targets. Here, using the Western Swiss Alps as a case study, we show how integrating species richness derived from species distribution model predictions for four taxonomic groups under present and future climate and land-use conditions into two conservation prioritization schemes can help optimize extant and future PAs. The first scheme, the “Priority Scores Method” identified priority areas for the expansion of the existing PA network. The second scheme, using the zonation software, allowed identifying priority conservation areas while incorporating global change scenarios and political costs. We found that existing mountain PAs are currently not situated in the most environmentally nor politically suitable locations when maximizing alpha diversity for the studied taxonomic groups and that current PAs could become even less optimum under the future climate and land-use change scenarios. This analysis has focused on general areas of high species richness or species of conservation concern and did not account for special habitats or functional groups that could have been used to create the existing network. We conclude that such an integrated framework could support more effective conservation planning and could be similarly applied to other landscapes or other biodiversity conservation indices.
Aim:
Species’ biogeographical patterns are already being altered by climate change. Here, we provide predictions of the impacts of a changing climate on species’ geographical ranges within high‐latitude mountain flora on a sub‐continental scale. We then examined the forecasted changes in relation to species’ biogeographic histories.
Location:
Fennoscandia, Northern Europe (55–72°N).
Methods:
We examined the sensitivity of 164 high‐latitude mountain species to changing climate by modelling their distributions in regard to climate, local topography and geology at a 1 km² resolution. Using an ensemble of six statistical modelling techniques and data on current (1981–2010) and future (2070–2099) climate based on three Representative Concentration Pathways (RCPs 2.6, 4.5, 8.5), we developed projections of current and future ranges.
Results:
The average species richness of the mountain flora is predicted to decrease by 15%–47% per 1 km² cell, depending on the climate scenario considered. Arctic flora is projected to undergo severe range loss along with non‐poleward range contractions, while alpine flora is forecasted to find suitable habitat in a warmer North. A substantial majority (71%–92%) of the studied species are projected to lose more than half of their present range by the year 2100. Species predicted to lose all suitable habitat had ranges centred in the northernmost (>68°N) part of continental Europe.
Main conclusions:
Climate change is predicted to substantially diminish the extent and richness of Europe's high‐latitude mountain flora. Interestingly, species' biogeographic histories affect their vulnerability to climate change. The vulnerability of true Arctic and endemic species marks them as highly important for conservation decisions.
The local weather and climate of the Himalayas are sensitive and interlinked with global-scale changes in climate, as the hydrology of this region is mainly governed by snow and glaciers. There are clear and strong indicators of climate change reported for the Himalayas, particularly the Jammu and Kashmir region situated in the western Himalayas. In this study, using observational data, detailed characteristics of long- and short-term as well as localized variations in temperature and precipitation are analyzed for these six meteorological stations, namely, Gulmarg, Pahalgam, Kokarnag, Qazigund, Kupwara and Srinagar during 1980–2016. All of these stations are located in Jammu and Kashmir, India. In addition to analysis of stations observations, we also utilized the dynamical downscaled simulations of WRF model and ERA-Interim (ERA-I) data for the study period. The annual and seasonal temperature and precipitation changes were analyzed by carrying out Mann–Kendall, linear regression, cumulative deviation and Student's t statistical tests. The results show an increase of 0.8 ∘C in average annual temperature over 37 years (from 1980 to 2016) with higher increase in maximum temperature (0.97 ∘C) compared to minimum temperature (0.76 ∘C). Analyses of annual mean temperature at all the stations reveal that the high-altitude stations of Pahalgam (1.13 ∘C) and Gulmarg (1.04 ∘C) exhibit a steep increase and statistically significant trends. The overall precipitation and temperature patterns in the valley show significant decreases and increases in the annual rainfall and temperature respectively. Seasonal analyses show significant increasing trends in the winter and spring temperatures at all stations, with prominent decreases in spring precipitation. In the present study, the observed long-term trends in temperature (∘Cyear-1) and precipitation (mmyear-1) along with their respective standard errors during 1980–2016 are as follows: (i) 0.05 (0.01) and -16.7 (6.3) for Gulmarg, (ii) 0.04 (0.01) and -6.6 (2.9) for Srinagar, (iii) 0.04 (0.01) and -0.69 (4.79) for Kokarnag, (iv) 0.04 (0.01) and -0.13 (3.95) for Pahalgam, (v) 0.034 (0.01) and -5.5 (3.6) for Kupwara, and (vi) 0.01 (0.01) and -7.96 (4.5) for Qazigund. The present study also reveals that variation in temperature and precipitation during winter (December–March) has a close association with the North Atlantic Oscillation (NAO). Further, the observed temperature data (monthly averaged data for 1980–2016) at all the stations show a good correlation of 0.86 with the results of WRF and therefore the model downscaled simulations are considered a valid scientific tool for the studies of climate change in this region. Though the correlation between WRF model and observed precipitation is significantly strong, the WRF model significantly underestimates the rainfall amount, which necessitates the need for the sensitivity study of the model using the various microphysical parameterization schemes. The potential vorticities in the upper troposphere are obtained from ERA-I over the Jammu and Kashmir region and indicate that the extreme weather event of September 2014 occurred due to breaking of intense atmospheric Rossby wave activity over Kashmir. As the wave could transport a large amount of water vapor from both the Bay of Bengal and Arabian Sea and dump them over the Kashmir region through wave breaking, it probably resulted in the historical devastating flooding of the whole Kashmir valley in the first week of September 2014. This was accompanied by extreme rainfall events measuring more than 620 mm in some parts of the Pir Panjal range in the south Kashmir.
Temperature regimes have multiple spatial and temporal dimensions that have different impacts on biodiversity. Signatures of warming across these dimensions may contribute uniquely to the large-scale species redistributions and abundance changes that underpin community dynamics. A comprehensive review of the literature reveals that 86% of studies were focused on community responses to temperature aggregated over spatial or temporal dimensions (e.g., mean, median, or extremes). Therefore, the effects of temperature variation in space and time on biodiversity remain generally unquantified. In the present article, we argue that this focus on aggregated temperature measures may limit advancing our understanding of how communities are being altered by climate change. In light of this, we map the cause-and-effect pathways between the different dimensions of temperature change and communities in space and time. A broadened focus, shifted toward a multidimensional perspective of temperature, will allow better interpretation and prediction of biodiversity change and more robust management and conservation strategies.
Conservation biology aims at identifying areas of rich biodiversity. Currently recognized global biodiversity hotspots are spatially too coarse for conservation management and identification of hotspots at a finer scale is needed. This might be achieved by identification of areas of endemism. Here, we identify areas of endemism in Iran, a major component of the Irano-Anatolian biodiversity hotspot, and address their ecological correlates. Using the extremely diverse sunflower family (Asteraceae) as our model system, five consensus areas of endemism were identified using the approach of endemicity analysis. Both endemic richness and degree of endemicity were positively related to topographic complexity and elevational range. The proportion of endemic taxa at a certain elevation (percent endemism) was not congruent with the proportion of total surface area at this elevation, but was higher in mountain ranges. While the distribution of endemic richness (i.e., number of endemic taxa) along an elevational gradient was hump-shaped peaking at mid-elevations, the percentage of endemism gradually increased with elevation. Patterns of endemic richness as well as areas of endemism identify mountain ranges as main centres of endemism, which is likely due to high environmental heterogeneity and strong geographic isolation among and within mountain ranges. The herein identified areas can form the basis for defining areas with conservation priority in this global biodiversity hotspot.
Significance
Mountain ranges constitute biodiversity hotspots, and montane species are shifting their ranges in elevation in response to climate change. Protecting elevational gradients can help fully capture montane biodiversity patterns and facilitate species range shifts. We map the protection of elevational gradients for mountain ranges worldwide to reveal where elevational protection is needed and may be optimized. Most of the world’s mountain ranges are narrowly protected and lack elevational distributions needed to preserve biodiversity. This could undermine the effectiveness of protected areas (PAs) under climate change. Strategic planning is required to prioritize elevational gradients in future PA establishment; otherwise, protecting roughly half of all mountainous area will be required to protect just 17% of land across nearly all elevational gradients.
Enhanced shrub growth and expansion are widespread responses to climate warming in many arctic and alpine ecosystems. Warmer temperatures and shrub expansion could cause major changes in plant community structure, affecting both species composition and diversity. To improve our understanding of the ongoing changes in plant communities in alpine tundra, we studied interrelations among climate, shrub growth, shrub cover and plant diversity, using an elevation gradient as a proxy for climate conditions. Specifically, we analyzed growth of bilberry (Vaccinium myrtillus L.) and its associated plant communities along an elevation gradient of ca. 600 vertical meters in the eastern European Alps. We assessed the ramet age, ring width and shoot length of V. myrtillus, and the shrub cover and plant diversity of the community. At higher elevation, ramets of V. myrtillus were younger, with shorter shoots and narrower growth rings. Shoot length was positively related to shrub cover, but shrub cover did not show a direct relationship with elevation. A greater shrub cover had a negative effect on species richness, also affecting species composition (beta-diversity), but these variables were not influenced by elevation. Our findings suggest that changes in plant diversity are driven directly by shrub cover and only indirectly by climate, here represented by changes in elevation.
Globally accelerating trends in societal development and human environmental impacts since the mid-twentieth century1-7are known as the Great Acceleration and have been discussed as a key indicator of the onset of the Anthropocene epoch6. While reports on ecological responses (for example, changes in species range or local extinctions) to the Great Acceleration are multiplying8, 9, it is unknown whether such biotic responses are undergoing a similar acceleration over time. This knowledge gap stems from the limited availability of time series data on biodiversity changes across large temporal and geographical extents. Here we use a dataset of repeated plant surveys from 302 mountain summits across Europe, spanning 145 years of observation, to assess the temporal trajectory of mountain biodiversity changes as a globally coherent imprint of the Anthropocene. We find a continent-wide acceleration in the rate of increase in plant species richness, with five times as much species enrichment between 2007 and 2016 as fifty years ago, between 1957 and 1966. This acceleration is strikingly synchronized with accelerated global warming and is not linked to alternative global change drivers. The accelerating increases in species richness on mountain summits across this broad spatial extent demonstrate that acceleration in climate-induced biotic change is occurring even in remote places on Earth, with potentially far-ranging consequences not only for biodiversity, but also for ecosystem functioning and services.
Land use contributes to environmental change, but is also influenced by such changes. Climate and atmospheric carbon dioxide (CO2) levels changes alter agricultural crop productivity, plant water requirements and irrigation water availability. The global food system needs to respond and adapt to these changes, for example by altering agricultural practices, including the crop types or intensity of management, or shifting cultivated areas within and between countries. As impacts and associated adaptation responses are spatially specific, understanding the land use adaptation to environmental changes requires crop productivity representations that captures spatial variations. The impact of variation in management practices, including fertiliser and irrigation rates, also needs to be considered. To date, models of global land use have selected agricultural expansion or intensification levels using relatively aggregate spatial representations, typically at a regional level, that are not able to characterise the details of these spatially differentiated responses. Here we show results from a novel global modelling approach using more detailed biophysically derived yield responses to inputs with greater spatial specificity than previously possible. The approach couples a dynamic global vegetative model (LPJ-GUESS) with a new land use and food system model (PLUMv2), with results benchmarked against historical land use change from 1970. Land use outcomes to 2100 were explored, suggesting that increased intensity of climate forcing reduces the inputs required for food production, due to the fertilisation and enhanced water use efficiency effects of elevated atmospheric CO2 concentrations, but requiring substantial shifts in the global and local patterns of production. The results suggest that adaptation in the global agriculture and food system has substantial capacity to diminish the negative impacts, and gain greater benefits from positive outcomes of climate change. Consequently, agricultural expansion and intensification may be lower than found in previous studies where spatial details and processes consideration were more constrained. This article is protected by copyright. All rights reserved.
Aim: Components of scale, such as grain, focus and extent, influence the spatial patterns of alpha and gamma diversity and the relationships between them. We explored these scale relations by testing whether the gamma diversity and alpha diversity along an elevation gradient were related independent of scale and whether the elevational patterns of herbaceous and woody species richness were dependent on scale.
Location: Langtang National Park, Nepal.
Methods: We estimated alpha diversity (plot richness) for woody and herbaceous plant species along an alpine elevation gradient (3,900–5,000 m a.s.l.) in nested plots of 1 m2, 16 m2 and 100 m2 and gamma diversity (regional richness) from published sources. Generalized linear modelling was used to analyse alpha and gamma diversity and their correspondence at different grain sizes.
Results: Elevational trends of gamma and alpha diversity were significantly correlated for both woody and herbaceous species at all grain sizes. The concordance increased with increasing grain size and area for gamma diversity estimation, particularly for the monotonously decreasing elevational gamma and alpha diversity patterns of woody species. The hump-shaped patterns of elevational gamma and alpha diversity for herbaceous species were also significantly correlated, but the concordance between the alpha diversity of herbaceous species and local gamma diversity was stronger. Elevational patterns of alpha diversity were coarsely consistent across grain sizes, although the patterns became more pronounced at larger grain sizes.
Main conclusions: The correspondence of elevational gamma and alpha diversity was largely scale invariant, implying that elevational and possibly other geographical diversity patterns can reliably be studied at different spatial scales. Nonetheless, the alpha diversity pattern was the least pronounced at fine grain size, particularly for woody life-forms. This finding suggests that for large-scale patterns such as elevational gradients at regional or continental scales, coarse grain sizes and large areas for gamma estimation are more appropriate.
The functional diversity and composition of plant traits within communities are tightly linked to important ecosystem functions and processes. Whereas vegetative traits reflecting adaptations to environmental conditions are commonly assessed in community ecology, floral traits are often neglected despite their importance for the plants’ life cycle. The consideration of floral traits covers important aspects such as sexual plant reproduction and pollinator diversity, which remain unobserved in studies focussing on vegetative traits only. To test whether vegetative and floral traits differ in their responses to elevation, we measured morphological and chemical traits of plant species occurring in pastures at seven elevations in the Austrian Alps. Variation in functional composition was examined using the concept of n-dimensional hypervolumes and vector analysis. Our data show that vegetative and floral traits vary differently with the elevational gradient. Whereas vegetative traits changed in a predictable manner with elevation, floral traits did not specifically respond to elevation. Overall variation in vegetative traits mainly resulted from phenotypical differences between plants in different elevations, whereas total variation in floral traits was a result from a high variation within communities. The assessment of functional changes in vegetative and floral traits along mountain slopes thus reveals different patterns in plant responses to elevation and may help to generate testable hypotheses on functional responses to current climate warming.
Climate change is affecting the composition and functioning of ecosystems across the globe. Mountain ecosystems are particularly sensitive to climate warming since their biota is generally limited by low temperatures. Cryptogams such as lichens and bryophytes are important for the biodiversity and functioning of these ecosystems, but have not often been incorporated in vegetation resurvey studies. Hence, we lack a good understanding of how vascular plants, lichens and bryophytes respond interactively to climate warming in alpine communities. Here we quantified long-term changes in species richness, cover, composition and thermophilization (i.e. the increasing dominance of warm-adapted species) of vascular plants, lichens and bryophytes on four summits at Dovrefjell, Norway. These summits are situated along an elevational gradient from the low alpine to high alpine zone and were surveyed for all species in 2001, 2008 and 2015. During the 15-year period, a decline in lichen richness and increase in bryophyte richness was detected, whereas no change in vascular plant richness was found. Dwarf-shrub abundance progressively increased at the expense of lichens, and thermophilization was most pronounced for vascular plants, but occurred only on the lowest summits and northern aspects. Lichens showed less thermophilization and, for the bryophytes, no significant thermophilization was found. Although recent climate change may have primarily caused the observed changes in vegetation, combined effects with non-climatic factors (e.g. grazing and trampling) are likely important as well. At a larger scale, alpine vegetation shifts could have a profound impact on biosphere functioning with feedbacks to the global climate.
In this short review, I will first summarize criteria by which environments can be considered “cold”, with plant stature (size, height above ground) playing a central role for the climate actually experienced. Plants adapted to such environments have to cope with both extremes and with gradual influences of low temperature. The first requires freezing resistance, which is tightly coupled to developmental state (phenology) and prehistory (acclimation). Gradual low temperature constraints affect the growth process (meristems) long before they affect photosynthetic carbon gain. Hence, plants growing in cold climates are commonly not carbon limited.
Understanding the relative importance of dispersal limitation and environmental filtering processes in structuring the beta diversities of subtropical forests in human disturbed landscapes is still limited. Here we used taxonomic (TBD) and phylogenetic (PBD), including terminal PBD (PBDt) and basal PBD (PBDb), beta diversity indices to quantify the taxonomic and phylogenetic turnovers at different depths of evolutionary history in disturbed and undisturbed subtropical forests. Multiple linear regression model and distance-based redundancy analysis were used to disentangle the relative importance of environmental and spatial variables. Environmental variables were significantly correlated with TBD and PBDt metrics. Temperature and precipitation were major environmental drivers of beta diversity patterns, which explained 7–27% of the variance in TBD and PBDt, whereas the spatial variables independently explained less than 1% of the variation for all forests. The relative importance of environmental and spatial variables differed between disturbed and undisturbed forests (e.g., when Bray-Curtis was used as a beta diversity metric, environmental variable had a significant effect on beta diversity for disturbed forests but had no effect on undisturbed forests). We conclude that environmental filtering plays a more important role than geographical limitation and disturbance history in driving taxonomic and terminal phylogenetic beta diversity.
Aim
In the alpine life zone, plant diversity is strongly determined by local topography and microclimate. We assessed the extent to which aspect and its relatedness to temperature affect plant species diversity, and the colonization and disappearance of species on alpine summits on a pan‐European scale.
Location
Mountain summits in Europe's alpine life zone.
Methods
Vascular plant species and their percentage cover were recorded in permanent plots in each cardinal direction on 123 summits in 32 regions across Europe. For a subset from 17 regions, resurvey data and 6‐year soil temperature series were available. Differences in temperature sum and Shannon index as well as species richness, colonization and disappearance of species among cardinal directions were analysed using linear mixed‐effects and generalised mixed‐effects models, respectively.
Results
Temperature sums were higher in east‐ and south‐facing aspects than in the north‐facing ones, while the west‐facing ones were intermediate; differences were smallest in northern Europe. The patterns of temperature sums among aspects were consistent among years. In temperate regions, thermal differences were reflected by plant diversity, whereas this relationship was weaker or absent on Mediterranean and boreal mountains. Colonization of species was positively related to temperature on Mediterranean and temperate mountains, whereas disappearance of species was not related to temperature.
Main conclusions
Thermal differences caused by solar radiation determine plant species diversity on temperate mountains. Advantages for plants on eastern slopes may result from the combined effects of a longer diurnal period of radiation due to convection cloud effects in the afternoon and the sheltered position against the prevailing westerly winds. In northern Europe, long summer days and low sun angles can even out differences among aspects. On Mediterranean summits, summer drought may limit species numbers on the warmer slopes. Warmer aspects support a higher number of colonization events. Hence, aspect can be a principal determinant of the pace of climate‐induced migration processes.
The spatial patterns of biodiversity and their underlying mechanisms have been an active area of research for a long time. In this study, a total of 63 samples (20m × 30m) were systematically established along elevation gradients on Mount Tai and Mount Lao, China. We explored altitudinal patterns of plant diversity in the two mountain systems. In order to understand the mechanisms driving current diversity patterns, we used phylogenetic approaches to detect the spatial patterns of phylogenetic diversity and phylogenetic structure along two elevation gradients. We found that total species richness had a monotonically decreasing pattern and tree richness had a unimodal pattern along the elevation gradients in the two study areas. However, altitudinal patterns in shrub richness and herbs richness were not consistent on the two mountains. At low elevation, anthropogenic disturbances contributed to the increase of plant diversity, especially for shrubs and herbs in understory layers, which are more sensitive to changes in microenvironment. The phylogenetic structure of plant communities exhibited an inverted hump-shaped pattern along the elevation gradient on Mount Tai, which demonstrates that environmental filtering is the main driver of plant community assembly at high and low elevations and inter-specific competition may be the main driver of plant community assembly in the middle elevations. However, the phylogenetic structure of plant communities did not display a clear pattern on Mount Lao where the climate is milder. Phylogenetic beta diversity and species beta diversity consistently increased with increasing altitudinal divergence in the two study areas. However, the altitudinal patterns of species richness did not completely mirror phylogenetic diversity patterns. Conservation areas should be selected taking into consideration the preservation of high species richness, while maximizing phylogenetic diversity to improve the potential for diversification in the future.
Aim
Higher‐elevation areas on islands and continental mountains tend to be separated by longer distances, predicting higher endemism at higher elevations; our study is the first to test the generality of the predicted pattern. We also compare it empirically with contrasting expectations from hypotheses invoking higher speciation with area, temperature and species richness.
Location
Thirty‐two insular and 18 continental elevational gradients from around the world.
Methods
We compiled entire floras with elevation‐specific occurrence information, and calculated the proportion of native species that are endemic (‘percent endemism’) in 100‐m bands, for each of the 50 elevational gradients. Using generalized linear models, we tested the relationships between percent endemism and elevation, isolation, temperature, area and species richness.
Results
Percent endemism consistently increased monotonically with elevation, globally. This was independent of richness–elevation relationships, which had varying shapes but decreased with elevation at high elevations. The endemism–elevation relationships were consistent with isolation‐related predictions, but inconsistent with hypotheses related to area, richness and temperature.
Main conclusions
Higher per‐species speciation rates caused by increasing isolation with elevation are the most plausible and parsimonious explanation for the globally consistent pattern of higher endemism at higher elevations that we identify. We suggest that topography‐driven isolation increases speciation rates in mountainous areas, across all elevations and increasingly towards the equator. If so, it represents a mechanism that may contribute to generating latitudinal diversity gradients in a way that is consistent with both present‐day and palaeontological evidence.
The Western Carpathians, as part of the Carpathian mountain range, are one of the most important centres of vascular plant endemism in Europe. We analysed the distribution patterns of 85 vascular plant taxa (excluding apomictic groups) that are endemic to this region (Western Carpathian endemics) or to the whole Carpathians (pan-Carpathian endemics) across 125 operational geographic units (OGUs) delimited in the area, and assessed their niche and altitudinal breadths, habitat preferences, and life-history traits. Spatial pattern of endemic richness was not random, but was geographically structured with the highest values recorded in the OGUs from the central part of the Western Carpathians. The pan-Carpathian endemics had, on average, larger distributional ranges in the Western Carpathians than the Western Carpathian endemics and showed slightly different distribution patterns, probably affected by historical migrations from the Eastern and Southern Carpathians. A significantly higher proportion of endemics occurred in open non-forest habitats (i.e. rocks/screes and grasslands, 74%) than in forests (18%). Almost 64% of endemic taxa occurred on calcareous bedrock, while only 12% and 21% were confined to siliceous or both types of bedrocks, respectively. We found a strong positive correlation between the distribution range of endemic taxa and altitudinal and niche breadths. There were no differences between diploids and polyploids in any of tested traits, niche and altitudinal breadths and range size. The best linear model explained almost 75% of endemic richness patterns, and included maximal altitude and its interactions with the proportion of calcareous areas and total area of OGUs as the best predictors. Our data suggest that both environmental conditions and historical migrations have shaped the current pattern of endemic richness in the Western Carpathians.
AimDespite the accumulation of cases describing fast radiations of alpine plants, we still have limited understanding of the drivers of speciation in alpine floras and of the precise the timing of their diversification. Here, we investigated spatial and temporal patterns of speciation in three groups of alpine Primulaceae. LocationMountains of the European Alpine System. Methods
We built a new phylogeny of Primulaceae including all species in three focal groups: Androsace sect. Aretia, Primula sect. Auricula and Soldanella. Combining phylogenetic information with a detailed climatic data set, we investigated patterns of range and ecological overlap between sister-species using an approach that takes phylogenetic uncertainty into account. Finally, we investigated temporal trajectories of diversification in the three focal groups. ResultsWe found that a large majority of sister-species pairs in the three groups are strictly allopatric and show little differences in substrate and climatic preferences, a result that was robust to phylogenetic uncertainty. While rates of diversification have remained constant in Soldanella, both Androsace sect. Aretia and Primula sect. Auricula showed decreased diversification rates in the Pleistocene compared to previous geological epochs. Main conclusionsAllopatric speciation with little niche divergence appears to have been by far the most common mode of speciation across the three groups studied. A few examples, however, suggest that ecological and polyploid speciation might also have played a role in the diversification of these three groups. Finally, extensive diversification likely occurred in the late Miocene and Pliocene coinciding with the later phases of the Alpine uplift, while diversification slowed down during subsequent glacial cycles of the Pleistocene.
The 5th edition of the GLORIA field manual represents the state of the art of the sampling methods for GLORIA's Multi-Summit approach. This revised manual is based on thorough discussions and agreements met at the GLORIA conference in Perth/Scotland in September 2010, which was attended by participants from 34 countries from all continents. The manual, further, contains additional approaches which may be applied in GLORIA target regions supplementary to the standard methods.
An annotated enumeration of vascular plants from the valleys and slopes of Nanga Parbat, West Himalaya is presented. 962 native or naturalised species (and 9 additional subspecies) as well as 3 hybrids are recorded. In addition, 106 species are recorded as doubtful; the occurrence of 32 cultivated taxa is documented. All this information is based on field observations, herbarium material, a critical evaluation of literature records and on hitherto unpublished floristic data from C. Troll’s 1937 expedition. The enumeration includes synonyms, vernacular and English names, data on local, altitudinal and general distribution, ecology, life-form, as well as information on status and (potential) utilisation.
Phytogeographically, the flora of Nanga Parbat is predominantly West Himalayan (26.8 %), with (Sino-) Himalayan elements comprising further 12.5 %. In accordance with the peripheral location on the extreme north-west edge of the Himalayas the Nanga Parbat flora is characterised by high proportions of Central Asian (8.6 %), Irano-Turanian (8.8 %) and Pamirean (7.9 %) elements, whereas Tibetan elements (1.9 %) are poorly represented. Within the flora of the Himalayas Nanga Parbat is a stronghold of Eurasiatic (Euro-Siberian, 13.2 %) and circumpolar elements (7.6 %). Considering the high amount of relief and climatic diversity endemics are not especially well represented and total c. 6.5 %. Cosmopolitan (2.0 %), subtropical (2.6 %), and Mediterranean elements (1.6 %) form minor floristic components.
Steep orographical and climatic-ecological gradients correspond with a high degree of altitudinal variation and form a prominent feature of the flora and vegetation. Vegetation belts and formations on Nanga Parbat range from the dry-subtropical valley bottom deserts of the Indus Valley (colline belt: 1100-2000 m) through steppes and forest (submontane: 2000-2700 m, montane: 2700-3400 m) to the tree-line, scrub, dwarf-scrub, turf, and finally open scree and rock (subalpine 3400-3900 m, alpine 3900-4500 m, subnival 4500-5300 m) on the upper edge of the phanerogamic vegetation.
Floristic data are presented and problems of biodiversity and chorology are discussed. Strong altitudinal differentiation with a pronounced maximum diversity at an altitude of about 2500-3800 m was observed. Patterns of distribution and diversity are discussed mainly in the context of geo-ecological constraints. A marked irregularity of diversity at about 2300 m seems to be related to relief features and climatic factors.
The rather short-termed and limited research project revealed no clear signs of change in the species inventory due to recent human interference. The annotated enumeration of vascular plants presented here may serve as basis for subsequent investigations into the dynamics of the flora. However, repeat photography revealed environmental changes during the past 60 years. The increasing human impact on the natural resource basis and possible future perspectives are also discussed.
AimIn recent decades species ranges have shifted upwards in elevation and northwards in latitude. These shifts are commonly interpreted as a response to recent climate warming. However, several alternative hypotheses have been proposed to explain the elevational shifts, including increased deposition of atmospheric nitrogen, changes in precipitation and dispersal limitation. We evaluate these hypotheses and attempt to identify the dominant drivers for the observed shifts in the upper range limits of alpine plant species.LocationEuropean mountains from Svalbard to the southern Alps.Methods
We assembled data on observed shifts in the upper range limit of alpine plants over 40 to 100 years on 114 mountains. We related the observed shifts to recent changes in temperature and precipitation and to recent deposition of atmospheric nitrogen. Changes in traits and habitat preferences of species in the summit assemblages were used to evaluate the potential role of different drivers.ResultsSeventy per cent of the species that showed a detectable change in their upper range limits between surveys shifted their range limits upwards. The same species tend to move up on different mountains. There are, however, large differences between mountains in the proportion of species shifting upwards. This proportion is not found to be statistically related to local changes in temperature. Correspondingly, warmth-demanding species did not move upward more frequently than expected by chance. Snow-bed species have become more common on summits.Main conclusionsOur data do not support the idea that climate warming is the dominant factor causing the observed range shifts of alpine plant species on European mountains: first, the amount of change in species assemblages on the summits studied is not related statistically to the amount of climate warming; second, those species that have moved upwards are not particularly warmth demanding.
The last decades have seen an upsurge in ecological studies incorporating phylogenetic information with increasing species samples, motivated by the common conjecture that species with common ancestors should share some ecological characteristics due to niche conservatism. This has been carried out using various methods of increasing complexity and reliability: using only taxonomical classification; constructing supertrees that incorporate only topological information from previously published phylogenies; or building supermatrices of molecular data that are used to estimate phylogenies with evolutionary meaningful branch lengths. Although the latter option is more informative than the others, it remains under-used in ecology because ecologists are generally unaware of or unfamiliar with modern molecular phylogenetic methods. However, a solid phylogenetic hypothesis is necessary to conduct reliable ecological analysis integrating evolutive aspects. Our aim here is to clarify the concepts and methodological issues associated with the reconstruction of dated megaphylogenies, and to show that it is nowadays possible to obtain accurate and well sampled megaphylogenies with informative branch-lengths on large species samples. This is possible thanks to improved phylogenetic methods, vast amounts of molecular data available from databases such as Genbank, and consensus knowledge on deep phylogenetic relationships for an increasing number of groups of organisms. Finally, we include a detailed step-by-step workflow pipeline (Supplementary material), from data acquisition to phylogenetic inference, mainly based on the R environment (widely used by ecologists) and the use of free web-servers, that has been applied to the reconstruction of a species-level phylogeny of all breeding birds of Europe.
The alpine zone of the Sierra Nevada of California, defined as non-forested areas at or above 3500 m, includes 385 species (409 taxa) of native vascular plants. Were the alpine boundary defined as at or above 3300 m, the alpine flora would grow to 536 species (570 taxa). There are 97 species that reach elevations of 4000 m and 27 species that reach to 4200 m. Over half of the alpine species occur in just six families, led by the Asteraceae (55 species, 59 taxa), Poaceae (39 species, 47 taxa), Brassicaceae (34 species), and Cyperaceae (31 species). The largest genus present is Carex with 29 species, and 18 more species would be added by lowering the alpine boundary to 3300 m. Next in size are Draba (14 species) and Lupinus (11 species, 16 taxa). Life forms of the flora are heavily dominated by broad-leaved erect perennials (50%), followed in importance by graminoid perennials (21%) and mats and cushions (11%). Annuals and woody shrubs each account for about 6% of the flora. Only nine species are obligate alpine taxa with a range restricted to elevations of 3500 m or above. An additional 67 species (17% of the flora) occur in both subalpine and alpine habitats but not lower. More than a quarter of the alpine species have elevational ranges that extend as low as foothill habitats defined as occurring below 1200 m. In terms of biogeographic affinities, the broad relationships of the flora include the cordillera of western North America (35%), Intermountain region of the Great Basin (20%), Sierra/Cascade axis (16%), and widespread distributions (14%). There are 36 species in the alpine flora endemic to the Sierra Nevada, and another 31 species that are Californian endemics.
Premise of the study:
With biodiversity and rates of climate change among the highest, the eastern Himalaya are critical for understanding the interaction of these two variables. However, there is a dearth of longitudinal data sets that address the effects of climate change on the exceptional alpine biodiversity of the Himalaya.
Methods:
We established permanent alpine vegetation monitoring plots in three mountain chains of the Hengduan Mountains, the easternmost Himalaya, which have warmed 0.03-0.05°C yr-1 since 1985. Recently, we resampled plots (176 1-m2 quadrat plots and 88 sections of 11 summits in three Hengduan mountain chains) to measure changes in vegetation after 7 years.
Key results:
Over 7 years, Tibetan alpine vegetation increased in number of species (+8 species/summit; +2.3 species/m2 ), in frequency (+47.8 plants/m2 ), and in diversity (+1.6 effective species/m2 ). Stepwise regressions indicated that warmer temperatures, southerly aspects, and higher elevations were associated with greater increases in these vegetation metrics. Unexpectedly, Himalayan endemic species increased (+1.4 species/m2 ; +8.5 plants/m2 ), especially on higher-elevation summits. In contrast, the increase in relative abundance of non-alpine species was greater at lower-elevation summits. Plants used by local Tibetans also increased (+1.3 species/m2 ; +32 plants/m2 ).
Conclusions:
As in other alpine areas, biodiversity is increasing with climate change in the Himalaya. Unlike other areas, endemic species are proliferating at the highest summits and are indicators of change.
Mountain ecosystems are sensitive and reliable indicators of climate change. Long-term studies may be extremely useful in assessing the responses of high-elevation ecosystems to climate change and other anthropogenic drivers from a broad ecological perspective. Mountain research sites within the LTER (Long-Term Ecological Research) network are representative of various types of ecosystems and span a wide bioclimatic and elevational range.
Here, we present a synthesis and a review of the main results from ecological studies in mountain ecosystems at 20 LTER sites in Italy, Switzerland and Austria covering in most cases more than two decades of observations. We analyzed a set of key climate parameters, such as temperature and snow cover duration, in relation to vascular plant species composition, plant traits, abundance patterns, pedoclimate, nutrient dynamics in soils and water, phenology and composition of freshwater biota.
The overall results highlight the rapid response of mountain ecosystems to climate change, with site-specific characteristics and rates. As temperatures increased, vegetation cover in alpine and subalpine summits increased as well. Years with limited snow cover duration caused an increase in soil temperature and microbial biomass during the growing season. Effects on freshwater ecosystems were also observed, in terms of increases in solutes, decreases in nitrates and changes in plankton phenology and benthos communities. This work highlights the importance of comparing and integrating long-term ecological data collected in different ecosystems for a more comprehensive overview of the ecological effects of climate change. Nevertheless, there is a need for (i) adopting co-located monitoring site networks to improve our ability to obtain sound results from cross-site analysis, (ii) carrying out further studies, in particular short-term analyses with fine spatial and temporal resolutions to improve our understanding of responses to extreme events, and (iii) increasing comparability and standardizing protocols across networks to distinguish local patterns from global patterns.
Plant endemism in the European Alps is clustered into particular geographic areas. Two contrasted and non exclusive hypotheses have been suggested to explain these hotspots of endemism: (i) those areas were glacial refugia, where endemism reflects survival-recolonisation dynamics since the onset of Pleistocene glaciations, (ii) those are high elevation mountain areas, where endemism was fostered by local speciation events due to geographic isolation and harsh environmental niches, or by low dispersal ability of inhabiting species.
What seems like a trivial task is one of the most difficult ones in functional plant ecology and biogeography: selecting the appropriate measures of temperature for an ecologically meaningful description of habitat conditions and for a mechanistic understanding of responses of plants. The difficulty becomes even more severe at elevations above the climatic tree limit, where plant stature, topography and seasonal snow cover interact in producing temperature conditions that largely deviate from weather station records. Temporal resolution and the distinction between extremes and means for biogeographic applications are emphasized. We summarize the key issues in handling temperature as a driver of plant life in general and in high elevation ecosystems in particular. Future directions in plant-temperature research at high elevation need to resolve the thermal species range limit issues (identify the fundamental temperature niche) and the complex controls of plant development (phenology) in a topography context.
An update of the Angiosperm Phylogeny Group (APG) classification of the orders and families of angiosperms is presented. Several new orders are recognized: Boraginales, Dilleniales, Icacinales, Metteniusiales and Vahliales. This brings the total number of orders and families recognized in the APG system to 64 and 416, respectively. We propose two additional informal major clades, superrosids and superasterids, that each comprise the additional orders that are included in the larger clades dominated by the rosids and asterids. Families that made up potentially monofamilial orders, Dasypogonaceae and Sabiaceae, are instead referred to Arecales and Proteales, respectively. Two parasitic families formerly of uncertain positions are now placed: Cynomoriaceae in Saxifragales and Apodanthaceae in Cucurbitales. Although there is evidence that some families recognized in APG III are not monophyletic, we make no changes in Dioscoreales and Santalales relative to APG III and leave some genera in Lamiales unplaced (e.g. Peltanthera). These changes in familial circumscription and recognition have all resulted from new results published since APG III, except for some changes simply due to nomenclatural issues, which include substituting Asphodelaceae for Xanthorrhoeaceae (Asparagales) and Francoaceae for Melianthaceae (Geraniales); however, in Francoaceae we also include Bersamaceae, Ledocarpaceae, Rhynchothecaceae and Vivianiaceae. Other changes to family limits are not drastic or numerous and are mostly focused on some members of the lamiids, especially the former Icacinaceae that have long been problematic with several genera moved to the formerly monogeneric Metteniusaceae, but minor changes in circumscription include Aristolochiaceae (now including Lactoridaceae and Hydnoraceae; Aristolochiales), Maundiaceae (removed from Juncaginaceae; Alismatales), Restionaceae (now re-including Anarthriaceae and Centrolepidaceae; Poales), Buxaceae (now including Haptanthaceae; Buxales), Peraceae (split from Euphorbiaceae; Malpighiales), recognition of Petenaeaceae (Huerteales), Kewaceae, Limeaceae, Macarthuriaceae and Microteaceae (all Caryophyllales), Petiveriaceae split from Phytolaccaceae (Caryophyllales), changes to the generic composition of Ixonanthaceae and Irvingiaceae (with transfer of Allantospermum from the former to the latter; Malpighiales), transfer of Pakaraimaea (formerly Dipterocarpaceae) to Cistaceae (Malvales), transfer of Borthwickia, Forchhammeria, Stixis and Tirania (formerly all Capparaceae) to Resedaceae (Brassicales), Nyssaceae split from Cornaceae (Cornales), Pteleocarpa moved to Gelsemiaceae (Gentianales), changes to the generic composition of Gesneriaceae (Sanango moved from Loganiaceae) and Orobanchaceae (now including Lindenbergiaceae and Rehmanniaceae) and recognition of Mazaceae distinct from Phrymaceae (all Lamiales).
Vegetation on mountains is expected to react in a highly sensitive way to climate change and species losses are predicted in the near future. By means of monitoring studies changes in species diversity can be continuously recorded. In this paper the results of a 7-year study in the Southern Alps are reported. As part of the worldwide network GLORIA (The Global Observation Research Initiative in Alpine Environments) four summits, at altitudes ranging from the treeline to the alpine-subnival ecotone (2199, 2463, 2757 and 2893 m a.s.l.) in the Dolomites (northern Italy) were studied. Sites on the four summits were used to determine the effects of climate warming and observe changes in the numbers of species of vascular plants, frequency and composition. It is hypothesized that 'thermophilization' is likely to occur over a period of 7 years (i.e. species from lower altitudes are expected to migrate to the summits due to climate warming). It is also hypothesized that nival, alpine-subnival and endemic species might decrease due to competitive displacement by species from lower altitudes. The summit areas were comprehensively sampled (from the highest point down to the 10 m contour line) in 2001, 2006 and 2008. In addition, 4 × 1 m2 permanent plots located 5 m below the highest summit point on the north, south, east and west sides of each summit were sampled. The results of revisiting the summits indicate that the numberof species increased on all four summits, with the greatest gains (15% and 18%) recorded on the two highest summits and moderate gains (4% and 9%) on the two lower summits. Species' frequencies within the 1 m2 plots also increased during the 2001-2008 period. A thermophilization trend was demonstrated in which species with distribution centres in the montane or tree line zones were found for the first time on three of the summits. On the lowest summit, the vigorous growth of trees and establishment of new saplings indicate an upward migration of the forest boundary. Species that disappeared from the four summits belonged to species with different altitudinal ranges; however, nival and subnivalalpine species remained. One endemic species, Potentilla nitida, disappeared from the highest summit. Further changes and clearer trends are expected in the next decade.
Abstract
Aim
Previous research on how climatic niches vary across species ranges has focused on a limited number of species, mostly invasive, and has not, to date, been very conclusive. Here we assess the degree of niche conservatism between distant populations of native alpine plant species that have been separated for thousands of years.
Location
European Alps and Fennoscandia.
Methods
Of the studied pool of 888 terrestrial vascular plant species occurring in both the Alps and Fennoscandia, we used two complementary approaches to test and quantify climatic-niche shifts for 31 species having strictly disjunct populations and 358 species having either a contiguous or a patchy distribution with distant populations. First, we used species distribution modelling to test for a region effect on each species' climatic niche. Second, we quantified niche overlap and shifts in niche width (i.e. ecological amplitude) and position (i.e. ecological optimum) within a bi-dimensional climatic space.
Results
Only one species (3%) of the 31 species with strictly disjunct populations and 58 species (16%) of the 358 species with distant populations showed a region effect on their climatic niche. Niche overlap was higher for species with strictly disjunct populations than for species with distant populations and highest for arctic–alpine species. Climatic niches were, on average, wider and located towards warmer and wetter conditions in the Alps.
Main conclusion
Climatic niches seem to be generally conserved between populations that are separated between the Alps and Fennoscandia and have probably been so for 10,000–15,000 years. Therefore, the basic assumption of species distribution models that a species' climatic niche is constant in space and time – at least on time scales 10 000 years or less – seems to be largely valid for arctic–alpine plants.
The flora of Middle Asia is very rich and diverse (Walter and Breckle 1986; Breckle and Agakhanjanz 1994). This is also true for the mountain floras of this orographically very complex region (Fig. 1). We will discuss the relationships of the various mountain floras and their diversity, how these floras developed and to which extent migration of plant species contributed to diversity. We will also investigate the tectonic history and more recent glacial history as decisive factors for the development of species richness in the mountains.
Current predictions of extinction risks from climate change vary widely depending on the specific assumptions and geographic and taxonomic focus of each study. I synthesized published studies in order to estimate a global mean extinction rate and determine which factors contribute the greatest uncertainty to climate change-induced extinction risks. Results suggest that extinction risks will accelerate with future global temperatures, threatening up to one in six species under current policies. Extinction risks were highest in South America, Australia, and New Zealand, and risks did not vary by taxonomic group. Realistic assumptions about extinction debt and dispersal capacity substantially increased extinction risks. We urgently need to adopt strategies that limit further climate change if we are to avoid an acceleration of global extinctions.
Copyright © 2015, American Association for the Advancement of Science.
This paper presents a perspective of how phylogenetic and phylogeographic hypotheses, based on nuclear DNA sequence variation (ITS) or amplified fragment length polymorphisms (AFLPs), can provide insights into the origin and evolution of the European high mountain flora. We focus on a diversity of unrelated herbaceous plant taxa that are broadly co-distributed across the European Alpine System, representing different taxonomic levels, and having either Mediterranean or Asian affinities (i.e., Anthyllis montana, Pritzelago alpina, Globularia vs. Soldanella, and Primula sect. Auricula). Our observations highlight that all taxa investigated began to diversify at the beginning of the Pleistocene or well within this period. Some of those taxa apparently followed different routes and modes of immigration, thereby colonizing the European high mountains only once (either from the East or the West) or repeatedly (from the Mediterranean Basin). Our observations further suggest that several high mountain taxa originated from lowland forms. While supporting earlier views, such a trend has generally been associated with pre-Quaternary rather than Pleistocene events. While several concordant patterns of (large-scale) spatial genetic differentiation are identified across taxa, such similarities may have arisen at either clearly different or roughly similar times. Finally, most speciation events likely occurred in allopatry, though more comprehensive studies are required to evaluate the relative importance of non-allopatric modes of speciation in the study area. We conclude that one major challenge to future evolutionary studies in European mountain plants is the accurate and reliable reconstruction of the tempo and mode of speciation across Quaternary time scales.
Understanding how species respond to climate change is critical for forecasting the future dynamics and distribution of pests, diseases and biological diversity. Although ecologists have long acknowledged species' direct physiological and demographic responses to climate, more recent work suggests that these direct responses can be overwhelmed by indirect effects mediated via other interacting community members. Theory suggests that some of the most dramatic impacts of community change will probably arise through the assembly of novel species combinations after asynchronous migrations with climate. Empirical tests of this prediction are rare, as existing work focuses on the effects of changing interactions between competitors that co-occur today. To explore how species' responses to climate warming depend on how their competitors migrate to track climate, we transplanted alpine plant species and intact plant communities along a climate gradient in the Swiss Alps. Here we show that when alpine plants were transplanted to warmer climates to simulate a migration failure, their performance was strongly reduced by novel competitors that could migrate upwards from lower elevation; these effects generally exceeded the impact of warming on competition with current competitors. In contrast, when we grew the focal plants under their current climate to simulate climate tracking, a shift in the competitive environment to novel high-elevation competitors had little to no effect. This asymmetry in the importance of changing competitor identity at the leading versus trailing range edges is best explained by the degree of functional similarity between current and novel competitors. We conclude that accounting for novel competitive interactions may be essential to predict species' responses to climate change accurately.