Subalpine Belt Research Articles

Changes of preferential flow path on different altitudinal zones in the Three Gorges Reservoir Area, China

Liu, M., Du, W. and Zhang, H. 2014. Changes of preferential flow path on different altitudinal zones in the Three Gorges Reservoir Area, China. Can. J. Soil Sci. 94: 177-188. Preferential flow in soil macropores plays an important role in runoff control and soil and water conservation. The aim of this study was to investigate the distribution of preferential flow paths in the soil profile of various altitudinal belts, analyze its variation among different soil horizons, and define the cause of soil macropores. A dye tracer method combined with photographic analysis was conducted for four hillslope sites in the Three Gorges Reservoir Area of China (TGRA). The results show that stained area proportion, as well as its vertical distribution in soil sections, presented varied patterns due to changes of forest vegetation and soil type with altitude. Stained area ratio of soil profiles increased, while stained depth decreased with increasing altitude. For soil sections in the subalpine belt, mid-mountain belt, a...

Growth, healthy status and seed production of differently aged allochtonous and autochtonous Pinus mugo stands in the Giant Mts. over 30 years

Plant communities with Dwarf pine (Pinus mugo var. pumilio) form characteristic vegetation in the subalpine belt of the Giant Mountains (Krkonose, Karkonosze and Riesengebirge, Czech Republic). This “island” of arcto-alpine tundra represents the northernmost edge of Dwarf pine natural range. We asked how concentration of sulphur in needles, growth, healthy status and fructification changed over three decades (1981–2011) with different air pollution in differently aged (45–120 years) autochtonous and allochtonous (introduced from the Alps) Dwarf pine stands. Different Dwarf pine stands above the alpine timberline were able to withstand 1980s, the period of heavy air pollution, without any decrease in growth rate or remarkable decrease in healthy status. Dwarf pine is thus highly tolerant to deposition of sulphur compounds. High concentration of SO2 in the air positively affected sulphur concentration in needles and eliminated thus sulphur deficiency. Higher germination rate of seeds in 2000s in comparison with 1980s indicate that the air pollution could decrease germination ability of seeds. High insect outbreaks (by Thecodiplosis brachyntera and Neodiprion sertifer) in 1990s and 2000s caused decrease in needle year classes. As there was a gradual increase in mean annual temperature over years 1981–2011, Dwarf pine stands can be more and more endangered by insect outbreaks in the future. There was no remarkable difference between autochtonous and allochtonous stands in all measured growth, healthy status and fructification characteristics. To determine real effects of air pollution and insect outbreaks on Dwarf pine stands from year to year fluctuations, decade-long monitoring is necessary.

Assessment of Hedysarum theinum Krasnob. (Fabaceae) population status in Altai

The status of 22 Hedysarum theinum cenopopulations (CPs) located in subalpine and alpine vegetation belts in Kazakhstan and Altai Republic is assessed by a complex of traits. It is detected that conditions of the subalpine belt (12 CPs), where the point sum of organismal and population traits vary from high to average values, are the most favorable for this species. The pessimal state, characterized by the smallest values of most species parameters, is determined in the alpine vegetation belt at an altitude of about 2000 m above sea level in Rudnyi Altai (Kazakhstan) and a shrub community at the junction of alpine and subalpine belts on the edge of the H. theinum area in Russian Altai.

Climatic and human impacts on mountain vegetation at Lauenensee (Bernese Alps, Switzerland) during the last 14,000 years

Lake sediments from Lauenensee (1381 m a.s.l.), a small lake in the Bernese Alps, were analysed to reconstruct the vegetation and fire history. The chronology is based on 11 calibrated radiocarbon dates on terrestrial plant macrofossils suggesting a basal age of 14,200 cal. BP. Pollen and macrofossil data imply that treeline never reached the lake catchment during the Bølling–Allerød interstadial. Treeline north of the Alps was depressed by c. 300 altitudinal meters, if compared with southern locations. We attribute this difference to colder temperatures and to unbuffered cold air excursions from the ice masses in northern Europe. Afforestation started after the Younger Dryas at 11,600 cal. BP. Early-Holocene tree- Betula and Pinus sylvestris forests were replaced by Abies alba forests around 7500 cal. BP. Continuous high-resolution pollen and macrofossil series allow quantitative assessments of vegetation dynamics at 5900–5200 cal. BP (first expansion of Picea abies, decline of Abies alba) and 4100–2900 cal. BP (first collapse of Abies alba). The first signs of human activity became noticeable during the late Neolithic c. 5700–5200 cal. BP. Cross-correlation analysis shows that the expansion of Alnus viridis and the replacement of Abies alba by Picea abies after c. 5500 cal. BP was most likely a consequence of human disturbance. Abies alba responded very sensitively to a combination of fire and grazing disturbance. Our results imply that the current dominance of Picea abies in the upper montane and subalpine belts is a consequence of anthropogenic activities through the millennia.

Procesos geomórficos históricos y su relación con la actividad humana en el Pirineo central español

The Central Spanish Pyrenees show a great diversity of geomorphic processes in relation with topographic and climatic heterogeneity and according to the strong altitudinal gradient. Human activity in the last millenniums has contributed to disturb the original landscape and its hydromorphological dynamics: the upper forest belt was eliminated by means of Jire during the Middle Age, in order to enlarge the extent of summer pastures; and the hillslopes located under 1600 m were cultivated in heavy topographic conditions, being frequently burnt in order to improve the quality of pastures. At present, evidences of this human activity are visible everywhere; in the subalpine belt mass movements and dense rill networks caused the loss of many soils and the expansion of gelifluxion terracettes; in middle mountain, overland flow has much increased the soil surface stoniness, and debris flows of different size have developed on the hillslopes and on the river channels. Rivers show a strong torrentiality, prevailing unstable channels and coarse sediment transport. The authors apport information on some historical geomorphic processes, related with human activity.

Unraveling the role of light and biotic interactions on seedling performance of four Pyrenean species along environmental gradients

The predicted upward displacement of forest species due to climate warming is expected to be modulated by a medley of abiotic and biotic factors acting at microsite level. Species-specific differences in plant responses to this set of environmental factors can thus have strong implications in the future dynamics of forest ecosystems. To gain a better understanding of the main fine-scale factors and processes driving present and future species performance in the montane and subalpine belt of the Eastern Pyrenees (NE Spain), we established a set of experimental mixed plantations along elevational and environmental gradients using the four tree species dominating these areas (Pinus sylvestris, Pinus uncinata, Abies alba and Betula pendula). Once the plantations had been established, the performance and growth of 72 seedlings of each species was monitored and linear and non-linear models were fitted to identify the main factors controlling their survival and growth.We found most of the mortality to occur during the third growing season, following a harsh winter and a drought period during summer. Mortality patterns were highly species- and site-specific. At the subalpine belt, shrubs were found to have a facilitative effect on winter survival of P. sylvestris (mortality<10%) but not on the other species. At the montane belt, A. alba mortality during the summer increased in areas with high light exposure and herbaceous cover (mortality>30%). All species except P. uncinata showed lower height growth at high elevation, with differences between sites matching differences in growing season duration (20%).Our results underline the strong impact that short periods of extreme climate can have in the performance of plants developing in mountainous areas far from their optimal elevational range. However, they also underline a potentially critical role played by biotic and abiotic microsite factors in mediating species responses to these climatic events.

Is land abandonment affecting forest dynamics at high elevation in Mediterranean mountains more than climate change?

Global change is leaving a fingerprint on the appearance, structure and productivity of the treeline ecotone, modifying patterns of mountain ecosystems. In order to implement correct policies for managing natural resources, we examine how climate change interrelated with land-use abandonment could shape mountain forests at their upper limit in a Mediterranean environment, and how patterns of tree growth and periods of tree establishment guide the interpretation of global change effects on treeline dynamics. We reconstructed the population dynamics of mountain pine (Pinus mugo Turra spp. mugo) in the subalpine belt of the Majella National Park (Italy). In a test area of 14,440 ha, proposed as a pilot study site for long-term ecological monitoring, temporal and spatial mountain pine distribution were examined since 1954 by historical aerial ortophotos. Multitemporal maps documented the expansion upwards (1 m/year) and downwards (3 m/year) of mountain pine. Mountain pine started to expand upwards into the formerly tree-free grassland in early 1900s, in association with a decline of the local human population and livestock. Land-use change was the major driving force of vegetation dynamics at the treeline in the Majella massif.

Ecological tree line history and palaeoclimate – review of megafossil evidence from the Swedish Scandes

The postglacial tree line and climate history in the Swedish Scandes have been inferred from megafossil tree remains. Investigated species are mountain birch (Betula pubescens ssp. czerepanovii), Scots pine (Pinus sylvestris) and grey alder (Alnus incana). Betula and Pinus first appeared on early deglaciated nunataks during the Lateglacial. Their tree lines peaked between 9600 and 9000 cal. a BP, almost 600 m higher than present‐day elevations. This implies (adjusted for land uplift) that early Holocene summer temperatures may have been 2.3°C above modern ones. Elevational tree line retreat characterized the Holocene tree line evolution. For short periods, excursions from this trend have occurred. Between c. 12 000 and 10 000 cal. a BP, a pine‐dominated subalpine belt prevailed. A first major episode of descent occurred c. 8200 cal. a BP, possibly forced by cooling and an associated shift to a deeper and more persistent snow pack. Thereafter, the subalpine birch forest belt gradually evolved at the expense of the prior pine‐dominated tree line ecotone. A second episode of pine descent took place c. 4800 cal. a BP. Historical tree line positions are viewed in relation to early 21st century equivalents, and indicate that tree line elevations attained during the past century and in association with modern climate warming are highly unusual, but not unique, phenomena from the perspective of the past 4800 years. Prior to that, the pine tree line (and summer temperatures) was consistently higher than present, as it was also during the Roman and Medieval periods, c. 1900 and 1000 cal. a BP, respectively.

Растительность севера Дальнего Востока России в картографических моделях

Distribution, configuration of vegetation zones and distribution of altitudinal belts on the North of the Russian Far East are characterized by their peculiarities caused by marginal position of the region on Eurasian continent, surrounding seas influence, altitude of the place. Areas types of vegetation complexes are established on the base of cartometric analysis of data-base of digital geobotanic large-scale map. The main regularities of differentiation of vegetation cover are revealed that are confirmed earlier known data. Types of arctic vegetation complexes are distributed through the whole territory of the region. Correlation between boreal and arctic vegetation complexes are characterized by zonal peculiarities. North-east boundary of boreal vegetation types is the important botanic-geographic frontier. To the south of this frontier wide zone of ecotone is noticed. In this zone forest vegetation types and tundra vegetation existed side by side on the placors habitats. The most distributed types are mountain vegetation type complexes with dominance of stone deserts, tundra siberian dwarf-pine. Vertical differentiation of mountain vegetation territories (taking in account zonalty) is reflected in subsequent change altitudinal belts where vegetation types complexes with dominance lichens mountain stone deserts, mountain tundra, siberian dwarf-pine (Pinus pumila), mountain open forests and larch (Larix cajanderi) and birch (Betula ermanii) forests are represented. Degree of revealing of vertical belts depends not only zonal conditions but also the altitude of the place above sea level, landscape peculiarities. Therefore separate belts, for example, mountain tundra, siberian dwarf-pine can be represented fragmentally. The stripe of ecotone usually can be noticed between alpine and subalpine belts. Vertical vegetation belts are evidently connected with horizontal zones of vegetation cover. In tundra zone 2 altitudinal belts can be noticed – alpine that is represented by lichens stone deserts, and subalpine that is formed mostly by mountain tundra. Mountain siberian dwarf-pine play big role in forest zone in formation of subalpine belt altogether with mountain tundra. Lower on the slopes prostrate shrubs are changed by forest belt (subzone of Larch open forests and forests, subzone of birch open forests and forests) or exist side by side with zonal prostrate shrubs and subarctic tundra (subzone of prostrate shrubs). Zonal vegetation complexes types (inhabit on placors and close to them habitats – plain low watershed areas, not steep mountain slopes, valleys between mountains, terraces near sea shore) are represented by arctic and subarctic tundra, siberian dwarf-pine (Pinus pumila), open forests and Larch (Larix cajanderi) and Birch (Betula ermanii) forests. Mires are dominated among zonal-interzonal vegetation type complexes. Valley forests, shrubs, tundra are distributed quite widely. Transitional structures, for example tundra-bogs are referred to this group of vegetation complexes. Vegetation that is transformed by strong stress factors (mostly natural and anthropogenic) is represented communities of plants formed under influence birds colonies, reindeer grazing, fire places, after technogenic disturbance as well as agricultural phytocoenosis.

Morphological variability of the two altitude vicariants, Anthoxanthum odoratum L. s.s. and Anthoxanthum alpinum in the Babia Góra Massif (Western Carpathian Mountains – Żywiec Beskid, Poland)

Anthoxanthum odoratum, a species occurring below the upper forest limit on the Babia Góra Mountain, is replaced by Anthoxanthum alpinum in the subalpine and alpine belts. It is a typical example of altitudinal vicariance. The aim of the study was to determine the range of morphological variability within the populations of A. odoratum and A. alpinum along an altitudinal transect. Special attention was paid to specimens growing in the transition zone between both species. Plant material was collected from 11 localities and samples were examined with respect to 24 morphological traits of the panicle. Results were analysed with the use of multidimensional statistical methods. It was found that A. alpinum grows above the upper forest limit. Populations of this species have a relatively small range of variability of the studied traits. Samples originating from the contact zone, situated at the altitude of c. 1166 m above sea level, consist of individuals representing both species. In turn, samples collected below the upper forest limit represent A. odoratum and occasionally A. alpinum, and reveal considerable morphological differentiation.

Impacts of introduced dwarf pine (Pinus mugo) on the diversity and composition of alpine vegetation

Dwarf pine (Pinus mugo) is a successful pioneer tree, but also an invader of the subalpine belt in Central-European mountains. In the Hrubý Jesenik Mts. (Czech Republic), dwarf pine was introduced at the end of the 19th century by humans into alpine communities. To analyse the influence of non-native woody species on species diversity, vegetation composition and the ecological bioindication of invaded alpine communities, three habitats (non-invaded alpine grasslands, gaps of alpine grasslands within dwarf pine stands and closed dwarf pine stands) were compared at two localities (Keprnik, Tabulove kameny) using the space-for-time substitution approach. Plant species composition was assessed by means of phytosociological releves, and bioindication by means of Ellenberg indicator values. At both localities, both beta and gamma diversity were lower, and species composition more uniform in dwarf pine plantations in contrast to the gaps within and alpine grasslands outside of dwarf pine stands. At Keprnik, alpha diversity was lower in the dwarf-pine plantation than outside of it, while at Tabulove kameny no significant differences were found. This is probably due to the somewhat different spatial structure of the dwarf pine stands and the different timing of dwarf pine introduction at these localities. Bioindication showed that dwarf-pine stands were drier, more shaded and had a higher soil fertility than alpine grasslands. Dwarf pine colonisation of alpine grasslands causes the extinction of many endangered plant species, complicating conservation goals. Because of the limited size of alpine areas, changes caused by dwarf pine in medium-high mountains might be more significant than in mountains with large alpine forest-free areas.

Biotic and abiotic responses to rapid Lateglacial climate change in the subalpine belt of the S Carpathians (Romania) - multi-proxy results from the PROLONGE project

Biotic and abiotic responses to rapid Lateglacial climate change in the subalpine belt of the S Carpathians (Romania) - multi-proxy results from the PROLONGE project

Classification of the High-Mountain Coniferous Forests in Taiwan

Vegetation of boreal coniferous forests has been extensively studied in many areas of northern Eurasia and North America, but similar forests in the high mountains of subtropical and tropical eastern Asia have been poorly documented so far. This paper, focusing on such forests, is the first phytosociological study at a national scale in Taiwan. The releves from the National Vegetation Diversity Inventory and Mapping Project database were used to define vegetation types of the high-mountain coniferous forests and to characterize their distribution in Taiwan. Environmental variables such as aspect, elevation, soil rockiness and slope were related to species composition. Cluster analysis was used to classify vegetation plots and establish groups that were interpreted as nine associations belonging to two alliances. The alliance Juniperion squamatae represents woodlands and forests scattered in the subalpine belt, in which Juniperus squamata dominates the canopy and subalpine meadow species occur in the understorey. The Abieti kawakamii-Tsugion formosanae alliance includes forests dominated by Abies kawakamii and Tsuga chinensis var. formosana with shade-tolerant herb species in the upper montane belt. In addition to regional vegetation description, an identification key for the studied forests was developed based on the classification tree technique.

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

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

Two New Tall Herb Communities with the Dominant Laserpitium Siler and Grafia Golaka from the Se Alps (Ne Italy, W Slovenia)

The article describes two new tall herb communities in the Southeastern Alps, Centaureo julici-Laserpitietum sileris and Laserpitio sileri-Grafietum golakae. Both are long-term successional stages in the overgrowing of abandoned hay meadows in the altimontane and subalpine belt of the southern and southwestern Julian Alps (including the Julian Prealps), partly also the Carnic Alps, that have been abandoned for over 50 years. In the succession sere where the altimontane-subalpine Illyrian beech forest (Dentario pentaphylli-Fagetum, Ranunculo platanifolii-Fagetum, Polysticho lonchitis-Fagetum) is the potential natural vegetation on steep, sunny limestone (rarely dolomite) slopes, the species Laserpitium siler and (or) Grafia golaka act as inhibitors also due to their high allelopathic potential; in turn, spontaneous afforestation with spruce and some deciduous trees has been slow and gradual.

Ecological and geochemical effect of evapotranspiration in the mountain-taiga and subalpine belts of the Northern Urals

The study presents data on the annual transport of 72 elements through evapotranspiration calculated for two mid-elevation mountain landscapes of the Northern Urals. It was found that the main characteristics of element transport in the mountain-taiga and subalpine belts are controlled by combined ecological and geochemical factors. A mechanism is described for changes in some environmental parameters through the air-borne migration of evapotranspiration products.

Holocene upper tree-limits of Pinus section sylvestris in the Western Alps as evidenced from travertine archives

The postglacial dynamics of Pinus sylvestris, Pinus mugo and Pinus uncinata are poorly documented in the Alps due to a lack of precise taxonomic resolution. We present past altitudinal distribution of these pine species, at a local scale, based on morphometric and taxonomic analyses of fossil cone imprints preserved in travertine deposits from the mountain and subalpine belt in the Western Alps. We found that P. sylvestris and P. uncinata have been present in the study area since at least 11,500 calibrated yr BP. Until 8500 cal yr BP, these conifers occupied likely a wide altitudinal range, favoured by the establishment of drier and warmer climate conditions compared to present-day. After this period, the dynamics and spatial distribution patterns of P. sylvestris and P. uncinata were strongly shaped by the expansion of more competitively superior conifers that had contributed to their local extinction from several sites and the fragmentation of their population.

Long-term fire and forest history of subalpine balsam fir (Abies balsamea) and white spruce (Picea glauca) stands in eastern Canada inferred from soil charcoal analysis

The northernmost balsam fir forest in eastern Canada forms disjunct stands far beyond the extensive balsam fir forest zone of southern Canada. The northern balsam fir stands are distributed in the subalpine belt of high plateaus and coexist locally with white spruce stands. These subalpine stands contrast greatly with black spruce forest stands located in lowlands. Given that subalpine stands are remnants of an earlier northern expansion of the balsam fir forest, the main objective of this study is to assess whether white spruce stands are distinct communities having diverged from the balsam fir forest community earlier in the Holocene or if they rather correspond to a different stage of the chronosequence within the subalpine belt. Macrofossil analysis of charcoal in mineral soils was used to compare the stand-scale fire histories and taxonomic fossil composition of subalpine, old-growth balsam fir stands and white spruce stands. No significant differences of mean number of observed fires (mean = 6.35 fires per site), Holocene fire recurrence at the landscape scale and mean fire-return interval (mean = 580 years) were found between white spruce stands and balsam fir stands. The botanical composition of charcoal fragments from mineral soils showed that Abies, Betula and Picea were present throughout the fire period from 5600 cal. BP to present, and no difference was found in the fossil composition of the balsam fir and white spruce stands. No historical change in the botanical composition of charcoal from soils of both stand types was observed indicating that the initial floristic composition remained through the period of recurrent fires. Charcoal data suggest that white spruce stands are not divergent community types. Rather, the two community types are arranged along a chronosequence of different successional stages within the subalpine relict flora.

Syntaxonomic revision and floristic characterization of the phytosociological alliances corresponding to subalpine and alpine grasslands of the Pyrenees and Cantabrian Mountains (classes Caricetea curvulae, Carici-Kobresietea, and Festuco-Seslerietea)

In this study, we made a numerical revision of the eight phytosociological alliances belonging to the classes Caricetea curvulae Br.-Bl. 1948, Carici rupestris-Kobresietea bellardii Ohba 1974, and Festuco-Seslerietea Barbéro & Bonin 1969. This analysis was designed to reveal the significant alliances corresponding to alpine and subalpine grasslands, review the associated syntaxonomical hierarchy, and establish the diagnostic floras of these alliances. The study area comprised the subalpine and alpine vegetation belts of the Pyrenees and the Cantabrian Mountains (northern Spain and southern France). We used 2259 floristic relevés, downloaded from the “Sistema de Información de la Vegetación Ibérica y Macaronésica” database, for statistical treatment. First, we classified the dataset, using the K-means clustering technique, so as to reveal a syntaxonomical structure. Second, we calculated the fidelity index Ochiai in all classification partitions. Finally, we compared the obtained lists with community descriptions from four bibliographical references. As a result, we could provide a diagnostic flora for every alliance. Therefore, we reconstructed seven of the eight alliances described. The numerical and bibliographical lists of characteristic species were similar for most syntaxa. Moreover, we proposed some new diagnostic species. Some alliances were considered more statistically robust than others. Finally, syntaxonomical repercussions have been suggested.

Two high-mountain burnet moth species (Lepidoptera, Zygaenidae) react differently to the global change drivers climate and land-use

Uphill shifts of alpine species have been associated with climate warming; however, land-use change can act simultaneously. We surveyed two related alpine burnet moth species in the Pyrenees to determine whether there was an uphill shift in the range of these two species and, if so, whether this was driven by climate and/or land-use changes. In 2008/09 we revisited 28 sites at the lower altitudinal range limits at which the species had been recorded between 1958 and 1986 (data were obtained from museum collections, distribution atlas, researchers’ field notes). We also recorded the recent upper range limits. The arctic-alpine Zygaena exulans showed an uphill shift (148m±SD 87m/decade) at all sites; at four sites the species has even become extinct. Changes in the lower altitudinal range limits were attributed to climate change. For the endemic species Zygaena anthyllidis we only ascertained an uphill shift at one third of the sites investigated (60m±SD 74m/decade); these shifts were due to changes in grazing intensities. As both species colonize very high summits, further uphill shifts of the upper limits are no longer possible. The studied con-generic species are affected by different global change drivers. Our data indicate the considerable role of land-use in conservation and suggest that it can even exceed the impact of climate change. Ongoing climate change is likely to jeopardize the long-term survival of Z. exulans in the Pyrenees; Z. anthyllidis, however, may be preserved by appropriate management in the subalpine belt.