Subalpine Meadows Research Articles

Климатогенные изменения луговых экосистем на Центральном Кавказе на примере особо охраняемых природных территорий

The basic trends of vegetation dynamics in meadow ecosystems of the Central Caucasus under the impact of current climatic changes were revealed on the example of sub-alpine meadows of the National Park <<Prielbrusye>> and Sukan plot of the Kabardino-Balkarian State High-Mountain Reserve. In the past 20 years, in the mountains of the Central Caucasus, during the period of active vegetation, the temperature increased by 0,46~С and precipitation by 16,24 mm, respectively. Humid subalpine meadows, which are indicators of climatic changes, are therewith more susceptible to climatic changes. Significant changes were registered in the following geobotanical and ecological parameters per 6--7 years. Mesophytous subalpine meadows are less susceptible. Steppe subalpine meadows are insignificantly responsive to current climatic changes.

Adsorption of Oxytetracycline on Subalpine Meadow Soil from Zoige Plateau, China: Effects of the Coexisting Cu2+

Adsorption of Oxytetracycline on Subalpine Meadow Soil from Zoige Plateau, China: Effects of the Coexisting Cu2+

Responses of subalpine meadow to climatic factors and the time lag effects in Wuyi Mountains from 2000 to 2019

Subalpine meadow is extremely sensitive to climate change. Few studies, however, focused on the responses of subalpine meadow to climatic factors in subtropical regions. It is still a challenge to extract the biophysical parameters from optical remote sensing imagery during the growing season. Based on the normalized difference vegetation index (NDVI) time series dataset from the MOD13Q1 vegetation index products and meteorological data, we analyzed the changes of vegetation growth of subalpine meadow at Huanggang Mountain in the top of Wuyishan National Park from 2000 to 2019, its responses to climate factors and the time lag effects. The results showed that NDVI in summer increased insignificantly during 2000-2019, and that NDVI in the growing season, spring, and autumn increased significantly. The enhancement of NDVI was mainly contributed by the increasing temperature (0.026 ℃·a-1) from 2000 to 2019. The increasing temperature in spring and autumn influenced meadow growth more than that in summer and growing season. NDVI of the growing season in subalpine meadow was sensitive to precipitation,indicating that the growth of subalpine meadow was strongly affected by precipitation even in the subtropical region with sufficient precipitation. Temperature and precipitation in different growth periods had different time lag effects on the NDVI of subalpine meadowo. The time lag effects of temperature on subalpine meadow were 0-1 month, and that of precipitation were 2-3 month.

Contrasting Patterns and Drivers of Soil Fungal Communities between Two Ecosystems Divided by the Treeline.

The treeline is a sensitive region of the terrestrial ecosystem responding to climate change. However, studies on the composition and formation mechanisms of soil fungal communities across the treeline are still lacking. In this study, we investigated the patterns of soil fungal community composition and interactions among functional guilds above and below the treeline using Illumina high-throughput sequencing and ecological network analysis. The results showed that there were significant differences in the soil environment and soil fungal community composition between the two ecosystems above and below the treeline. At the local scale of this study, geographic distance and environmental factors affected the composition of the soil fungal community. Soil temperature was an important environmental predictor of soil fungal community composition. Species in soil fungal communities in the subalpine meadow were more closely related to each other compared to those in the montane forest. Furthermore, the soil fungal community in montane forest was more stable. Our findings contribute to a better understanding of how mountain ecological functions respond to global climate change.

Diverse responses of grassland dynamics to climatic and anthropogenic factors across the different time scale in China

An accurate quantification in the separation of the relative contributions of climate change and human activities on grassland dynamics is crucial for controlling grassland degradation. Here, we investigated grassland dynamics in China by using net primary productivity (NPP) as an evaluation indicator from 1982 to 2016. We calculated the human-induced grassland NPP (HNPP) by subtracting the potential NPP (PNPP) from the actual NPP (ANPP) to distinguish the climatic and anthropogenic effects on grassland NPP changes across different time scales. Results indicated that the change in grassland ANPP resulted from different dominated factors in the two periods of 1982–1999 and 2000–2016. An obvious increase of grassland ANPP was observed from 1982 to 1999, which mainly due to a slight increasing trend in grassland PNPP driven by a humid-warm climate and a slight decrease in grassland HNPP from weak human activities. An overall increase in ANPP (69.576%) over its decrease portion (30.424%) was observed from 1982 to 1999. Human activities-induced ANPP increase mainly occurred in Shaanxi, Qinghai and Gansu Provinces and Tibet Autonomous Region for the grassland types of Alpine subalpine meadow, Meadow and Slope grassland. Climate-dominated decrease mainly occurred in Shanxi, Shaanxi and Heilongjiang, especially for Plain and Slope grassland. However, an overall decreasing trend of grassland ANPP was observed from 2000 to 2016, mainly attributed to a decreasing trend in grassland HNPP by human intervention and a warm-dry climate-induced negative effect on grassland growth. Overall, the grassland underwent a decrease than increase in ANPP (58.826% vs 41.174%) during 2000–2016; the contributions of climate factors to grassland ANPP increase was relatively greater than that of human factors in Xinjiang, Qinghai and Inner Mongolia. Human activities-dominated ANPP decrease occupied 23.913%, obviously higher than the decrease dominated by climate change (9.248%), which mainly occurred in Alpine subalpine meadow, Desert grassland and Alpine subalpine grassland. Overall, these findings seem to demonstrate that there are great differences in the temporal and spatial effects of climate change and human activities on different regions and different grassland types in China before and after 1999, and contribute to providing location guidance for future grassland restoration. Meanwhile, this study is expected to improve the understanding of the driving mechanisms of grassland dynamics, and provide support for scientifically evaluating and adjusting ecological restoration policies in China.

RARE FLORA AND VEGETATION OF THE BORZHAVSK MOUNTAIN MASSAGE OF THE UKRAINIAN CARPATHIANS AND PROSPECTS OF THEIR PROTECTION

The Borzhavsky mountain range of the Ukrainian Carpathians has long served as a fodder base for livestock and the richest massif of blueberry reserves in the Ukrainian Carpathians. Therefore, its flora and vegetation have undergone significant changes. Nevertheless, a number of nature protection sites, mostly forest reserves, (with a total area oabout 4,000 hectares) have been created around the subalpine meadows (Polonyny). At the same time, polonyny still remain unprotected. In the study area we identified 32 species of vascular plants included in the Red Book of Ukraine (2009) and seven plant communities included in the Green Book of Ukraine (2009). The article presents their sozological, synphyto sozological and biotopic analysis. More representatives of the flora grow in the subalpine meadows, which indicates the need for their protection. Among them there are 9 rare, 15 vulnerable and 8 invaluable species. The largest number of coenopopulations of the rare relict arcto-alpine species Diphasiastrum alpinum (L.) Holub is concentrated in this massif in the Ukrainian Carpathians.Some other sozophytes (Lunaria rediviva L., Lilium martagon L., Allium ursinum L.) and rare forest communities with their participation are most often found on it. Among the rare communities are three associations with the status of "endangered" and four associations with the status of "rare".

Conifer Establishment and Encroachment on Subalpine Meadows around Mt. Baker, WA, USA

The subalpine ecotone is experiencing significant changes in habitat availability and connectivity as a result of climate change. The conversion of meadow habitats to forests has been observed in many mountainous regions. Rates of conifer encroachment into meadows appears to have increased in the 20th century, but the patterns of conifer establishment seem highly variable over both space and time. To understand how and why these changes vary temporally and spatially in the Pacific Northwest, we collected cross-sections and whorl counts from conifers along four transects in subalpine meadows around Mt. Baker, Washington. We quantified the relationships between temporal patterns of conifer establishment and a suite of climate variables, and between spatial patterns of conifer density and microsite characteristics. Our results show that establishment occurred in pulses throughout the 20th century, with greater establishment on drier sites during periods of greater precipitation, and greater establishment on wetter sites during periods of higher temperatures. We found that April precipitation and September temperature are particularly strongly correlated with establishment rates, suggesting that the best conditions for conifer seedling establishment occur in years with the warmth and soil moisture needed for the growing season to start earlier or last longer. Within individual meadows, conifer seedling establishment was greater on convex surfaces and in areas with a higher percentage of Vaccinium cover. Our findings at Mt. Baker show that periods of conifer establishment occurred somewhat synchronously across multiple mountains in the region, but we also identified distinct spatial and temporal differences linked to local site conditions.

Shifts and plasticity of plant leaf mass per area and leaf size among slope aspects in a subalpine meadow.

The composition of vegetation on a slope frequently changes substantially owing to the different micro‐environments of various slope aspects. To understand how the slope aspect affects the vegetation changes, we examined the variations in leaf mass per area (LMA) and leaf size (LS) within and among populations for 66 species from 14 plots with a variety of slope aspects in a subalpine meadow. LMA is a leaf economic trait that is tightly correlated with plant physiological traits, while the LS shows a tight correlation with leaf temperature, indicating the strategy of plants to self‐adjust in different thermal and hydraulic conditions. In this study, we compared the two leaf traits between slope aspects and between functional types and explored their correlation with soil variables and heat load. Our results showed that high‐LMA, small‐leaved species were favored in south‐facing slopes, while the reverse was true in north‐facing areas. In detail, small dense‐leaved graminoids dominated the south slopes, while large thin‐leaved forbs dominated the north slopes. Soil moisture and the availability of soil P were the two most important soil factors that related to both LMA and LS, and heat load also contributed substantially. Moreover, we disentangled the relative importance of intraspecific trait variation and species turnover in the trait variation among plots and found that the intraspecific variation contributed 98% and 56% to LMA and LS variation among communities, respectively, implying a large contribution of intraspecific trait plasticity. These results indicate that LMA and LS are two essential leaf traits that affect the adaptation or acclimation of plants underlying the vegetation composition changes in different slope aspects in the subalpine meadow.

Grazing alters species relative abundance by affecting plant functional traits in a Tibetan subalpine meadow.

Domestic livestock grazing has caused dramatic changes in plant community composition across the globe. However, the response of plant species abundance in communities subject to grazing has not often been investigated through a functional lens, especially for belowground traits. Grazing directly impacts aboveground plant tissues, but the relationships between above‐ and belowground traits, and their influence on species abundance are also not well known. We collected plant trait and species relative abundance data in the grazed and nongrazed meadow plant communities in a species‐rich subalpine ecosystem of the Qinghai–Tibet Plateau. We measured three aboveground traits (leaf photosynthesis rate, specific leaf area, and maximum height) and five belowground traits (root average diameter, root biomass, specific root length, root tissue density, and specific root area). We tested for shifts in the relationship between species relative abundance and among all measured traits under grazing compared with the nongrazed meadow. We also compared the power of above‐ and belowground traits to predict species relative abundance. We observed a significant shift from a resource conservation strategy to a resource acquisition strategy. Moreover, this resource conservation versus resource acquisition trade‐off can also determine species relative abundance in the grazed and nongrazed plant communities. Specifically, abundant species in the nongrazed meadow had aboveground and belowground traits that are associated with high resource conservation, whereas aboveground and belowground traits that are correlated with high resource acquisition determined species relative abundance in the grazed meadow. However, belowground traits were found to explain more variances in species relative abundance than aboveground traits in the nongrazed meadow, while aboveground and belowground traits had comparable predictive power in the grazed meadow. We show that species relative abundance in both the grazed and the nongrazed meadows can be predicted by both aboveground traits and belowground traits associated with a resource acquisition versus conservation trade‐off. More importantly, we show that belowground traits have higher predictive power of species relative abundance than aboveground traits in the nongrazed meadow, whereas in the grazed meadows, above‐ and belowground traits had comparable high predictive power.

Spatial variations in soil organic carbon, nitrogen, phosphorus contents and controlling factors across the “Three Rivers” regions of southwest China

Based on the data of China Geochemical Baselines project, geostatistical analysis was used to investigate the spatial variations in soil organic carbon (SOC), total nitrogen (TN) and total phosphorus (TP) contents across the “Three Rivers” regions of southwest China, and the factors affecting them were analyzed by the redundancy analysis (RDA) and Person's correlation. Results showed that, the average content of SOC, TN and TP in the study area were 7.20 g/kg, 0.84 g/kg and 0.55 g/kg, respectively. The SOC and TN contents showed an obvious enrichment characteristic with great spatial variability, while TP content was stable on regional scale. The SOC, TN and TP contents decreased with elevation increase in the northern frigid highland, but showed an opposite character in the southern tropical & subtropical, which actually reflected the control of temperature on them. Combined with that there were higher SOC, TN and TP contents in subalpine meadow soil and red earth–yellow earth of the middle latitude zone, these suggested that the suitable temperature was conducive to the accumulation of soil nutrients. The weak positive correlation between population density and soil nutrients, together with high level of soil nutrients in the vicinity of large cities, demonstrated that human activities had significantly increased the soil nutrients contents in the study area. The RDA results showed that soil nutrients in the northern frigid highland were mainly controlled by the environmental factors dominated by temperature and soil structural factors dominated by parent materials with the total explanatory power as high as 75.87%, while in the southern tropical & subtropical mainly by the environmental factors dominated by chemical and biological weathering and the biological factors dominated by vegetation with the total explanatory power as high as 88.53%. The above factors superimposing a certain degree of human activities converged to cause that the SOC and TP contents in the south were higher than that in the north while the TN content was lower than that in the north.

Can flowers affect land surface albedo and soil microclimates?

The phenology of vegetation, namely leaf-out and senescence, can influence the Earth's climate over regional spatial scales and long time periods (e.g., over 30 years or more), in addition to microclimates over local spatial scales and shorter time periods (weeks to months). However, the effects of flowers on climate and microclimate are unknown. We investigate whether flowers can influence light reflected by the land surface and soil microclimate in a subalpine meadow. We conducted a flower removal experiment with a common sunflower species, Helianthella quinquenervis, for 3 years (2015, 2017, and 2019). The flower removal treatment simulates the appearance of the meadow when Helianthella flowers earlier under climate change and loses its flowers to frost (other plant structures are not damaged by frost). We test the hypotheses that a reduction in cover of yellow flowers leads to a greener land surface, lower reflectance, warmer and drier soils, and increased plant water stress. Flower removal plots are greener, reflect less light, exhibit up to 1.2 °C warmer soil temperatures during the warmest daylight hours, and contain ca. 1% less soil moisture compared to controls. However, soils were warmer in only 2 of the 3 years, when flower abundance was high. Helianthella water use efficiency did not differ between removal and control plots. Our study provides evidence for a previously undocumented effect of flowers on soil microclimate, an effect that is likely mediated by climate change and flowering phenology. Many anthropogenic environmental changes alter landscape albedo, all of which could be mediated by flowers: climate change, plant invasions, and agriculture. This study highlights how further consideration of the effects of flowers on land surface albedo could improve our understanding of the effects of vegetation on microclimate.

Effects of short-term grazing prohibition on soil physical and chemical properties of meadows in Southwest China.

BackgroundGrassland plays an important role in the ecosystem, but overgrazing harms the grassland system in many places. Grazing prohibition is an effective method to restore grassland ecosystems, and it plays a great role in realizing the sustainable development of grassland systems. Therefore, it is necessary to carry out research on the influence of regional grazing prohibition on the physical and chemical properties of different grassland systems.MethodsIn Potatso National Park, Southwest China, we selected experimental plots in the artificial grazing meadow area to study the effects of grazing prohibition on plant and soil indexes in subalpine meadows and swamp meadows. We investigated the biomass and species diversity of grazing prohibition treatment and grazing treatment plots and sampled and tested the soil index. The variation percentage was used to remove the original heterogeneity and yearly variation, allowing us to compare differences in plant index and soil index values between grazing prohibition and grazing treatments.ResultsGrazing prohibition increased the aboveground biomass, total biomass, total meadow coverage, average height, richness index, Shannon diversity index and evenness index and reduced the belowground biomass and root/shoot ratio in the subalpine meadow and swamp meadow. Additionally, grazing prohibition reduced the pH and soil bulk density and increased the soil total carbon, soil organic carbon, soil total nitrogen, soil hydrolyzable nitrogen, soil total phosphorus and soil available phosphorus in the subalpine meadow and swamp meadow. Nonmetric multidimensional scaling (NMDS) analysis showed that both plant indexes and soil indexes were significantly different between grazing and grazing prohibition treatments and between meadow types. Short-term grazing prohibition had a great impact on improving the fertility of meadow soil in the study area. We suggest that long-term and extensive research should be carried out to promote the restoration and sustainable development of regional grassland systems.

Plant Community Assembly Mechanisms of a Subalpine Meadow Community Along Different Successional Time

The process of community assembly is important to explain species coexistence and the maintenance of species diversity. Succession provides a good opportunity to study the role of the deterministic and stochastic processes during the community species composition. We investigated species composition and environmental factors and calculated the change in species diversity, phylogenetic diversity, net relatedness index, and nearest taxon index along a successional chronosequence, with a series of 0.5 × 0.5 m2 plots (n = 20) from five successional subalpine meadow plant communities (ages 1, 3, 5, 15, and 30) in the Qinghai-Tibetan Plateau. In the plots, we found a significant change in species composition and abiotic environmental factors. Our redundancy analysis showed that soil nitrate nitrogen and soil organic carbon were the key environmental factors that affect the community composition in succession gradient. The community showed an overdispersion phylogenetic structure along with the early and medium succession. The ends of the succession stage showed a random or convergent phylogenetic structure. The results showed that the construction process of plant communities in the early and middle stages of succession was mainly affected by habitat filtering. In the late stage of succession, the process of community construction is more complex, which could be affected by the limiting similarity and neutral driving process. Our findings are important to be used in managing ecological restoration and protection.

Establishment and Survival of Subalpine Fir (Abies lasiocarpa) in Meadows of Olympic National Park, Washington

Establishment of trees in subalpine meadows is a potential indicator of ecological effects of climate change. Tree establishment is a multi-year process including cone and seed production, germination, establishment, and growth, with each demographic step possibly sensitive to different climate limitations. While most studies have focused on one or a few steps, this study follows a cohort of individually marked saplings for 27 years beginning as seeds in two meadows on Hurricane Ridge, Olympic National Park. These meadows are examples of a south-facing tall sedge community type rather than the north-facing heath-shrub type where establishment has usually been observed. Results showed that mortality was high for the first few years, but number of saplings stabilized after the first decade. Seedling mortality during germination and establishment was directly related to weather that resulted in high air and soil temperatures and drought, while mortality of established saplings was indirectly related to weather through effects on growth. Growth was enhanced by longer growing season and warmer minimum temperatures; growth over three years and sapling height were predictive of mortality. Most sapling survival occurred in lichen (primarily Trapeliopsis granulosa) and Vaccinium deliciosum plant communities. Many saplings are growing at very low rates compared with the rate predicted from adult trees. It is also apparent that while microsite within meadow (e.g., relative snow depth) is important in determining sapling success, the landscape position of meadows (e.g., north versus south aspect) exerts a higher-level control over whether a subalpine meadow is likely to disappear with warming climate.

Plant-pollinator interactions between generalists persist over time and space.

Generalist species are the linchpins of networks, as they are important for maintaining network structure and function. Previous studies have shown that interactions between generalists tend to occur consistently across years and sites. However, the link between temporal and spatial interaction persistence across scales remains unclear. To address this gap, we collected data on plant-pollinator interactions throughout the flowering period for 5 yr across six plots in a subalpine meadow in the Rocky Mountains. We found that interactions between generalists tended to persist more in time and space such that interactions near the network core were more frequently recorded across years, within seasons, and among plots. We posit that species' tolerance of environmental variation across time and space plays a key role in generalization by regulating spatiotemporal overlap with interaction partners. Our results imply a role of spatiotemporal environmental variation in organizing species interactions, marrying niche concepts that emphasize species environmental constraints and their community role.

Pollinator sharing among co-flowering plants mediates patterns of pollen transfer

Co-flowering plant species often share pollinators, which could result in interspecific pollination. Despite some evidence suggesting plant species with overlapping pollinators influence each other’s pollination, the relationship between pollinator sharing and heterospecific pollen transfer (HPT) is not well explained at the community level. Here, we sampled a plant-pollinator visitation network to calculate the degree of pollinator sharing, and we identified pollen deposition on stigmas of co-flowering species to construct a HPT network in a sub-alpine meadow in southwest China. We also analyzed floral colour using reflectance spectra to measure the flower reflectance dissimilarity between each pair species. We found that there was no pollen transfer between most species pairs with shared pollinators. A higher proportion of HPT links between plant species pairs with shared pollinators was observed than between pairs with distinct pollinators. More pollen grains were transferred from donor to recipient species with greater pollinator sharing. Flowers with more dissimilar flower colours exchanged less heterospecific pollen. Our study evaluated the effect of pollinator sharing in shaping pollen transfer patterns among co-flowering species, which may shed light on the ecological implications of plant–pollinator interactions, mediated by pollinator sharing.

Evaluating the dynamics of grassland net primary productivity in response to climate change in China

Net primary productivity (NPP) has been considered as a direct indicator to access the terrestrial primary production. However, considerable uncertainties remain toward the response mechanism of NPP to climate change across annual and seasonal scales, especially for grassland ecosystems. In this study, the spatiotemporal dynamics of grassland NPP and its prominent climate-controlling factor were evaluated based on the CASA model and ground-based meteorological data across annual and seasonal scales in China from 1982 to 2016. Results showed that the annual mean grassland NPP was 294.58 gC·m−2·a−1 over the 35 years; the largest annual mean NPP was observed in Alpine sub-alpine meadow (235.72 ± 13.21 gC·m−2·a−1), while the smallest annual mean NPP value occurred in Desert grassland (97.27 ± 9.64 gC·m−2·a−1). Moreover, the multiyear mean grassland NPP showed a decreasing trend from the southeast to the northwest spatially. Temporally, grassland NPP exhibited a significant increasing trend (slope = 2.4 gC·m−2·a−1; p < 0.0001) over the whole study period; an abrupt change point across the grassland NPP time series was observed in 1999. Specially, 66.34% of the grassland area showed an increasing trend in NPP, and the areas with a significant increasing trend were concentrated in Qinghai-Tibet Plateau and the northern area of Xinjiang. Further climate factor analysis with NPP indicated that NPP positively correlated with precipitation and negatively correlated with temperature for the whole grassland area. In particular, the temperature was a dominant driver in NPP variations for Alpine sub-alpine meadow, Slope grassland and Alpine sub-alpine grassland, while precipitation controlled the most in NPP variations for Plain grassland and Desert grassland. The accumulation of grassland NPP in spring and autumn benefits from the increase in temperature, and precipitation promoted the accumulated NPP in summer and winter.

Functional diversity and redundancy of subalpine meadows subjected to anthropogenic disturbances

Abstract Aims The aims of this study were to assess how functional diversity (FD) and functional redundancy respond to subalpine meadow ecosystem degradation under anthropogenic disturbance and how species contribute to functional redundancy along the disturbance gradient. Methods The study was carried out in the subalpine meadow in Mount Jade Dragon, which is located at the southeastern edge of the Tibetan Plateau. Four disturbance intensities [no disturbance (ND), weak disturbance (WD), moderate disturbance (MD) and severe disturbance (SD)] were identified. Species richness, soil properties and five key plant functional traits were assessed along the disturbance gradient. Simpson’s diversity index, FD based on the Rao algorithm, functional redundancy, community-weighted mean of each functional trait and species-level functional redundancy were determined. Important Findings Unimodal change pattern of FD and functional redundancy along the disturbance gradient were found in the present study, with their maximum in MD and WD, respectively. Species diversity showed a decreasing trend with increasing disturbance intensity. As disturbance intensified, species with traits related to conservative growth strategies, such as low specific leaf area (SLA) and high leaf dry matter content (LDMC), decreased, whereas species with resource acquisitive strategies, such as small plant, high SLA and low LDMC, increased in the community. At the species level, species showed species-specific roles in functional redundancy. Notably, some species were important in the community in terms of their unique function. For instance, Ligularia dictyoneura in ND and Potentilla delavayi in MD and SD.

Relationship between surface pollen and modern vegetation in northern Xinjiang, China: Implications for paleovegetation and paleoclimate reconstruction

The relationship between surface pollen and modern vegetation is an important criterion for interpreting fossil pollen spectra in reconstructing of paleovegetation and the paleoenvironment. A total of 438 surface pollen samples were collected from the Junggar Basin, Tianshan and Altai Mountains, and other areas in northern Xinjiang, China. Surface pollen assemblages were divided into five horizontal pollen zones: alpine and subalpine meadows, mountain forests, steppes, deserts, and wetlands. A high abundance of tree pollen was detected in the Altai and Tianshan Mountains, primarily originating from conifers such as Picea and Larix. Desert steppe vegetation was predominant on both sides of the central Junggar Basin, with significant amounts of pollen from Ephedra, Chenopodiaceae, and Artemisia. The geographic distribution of the pollen source sites was analyzed using ArcGIS. R-value, Pearson correlation analysis, and principal component analysis were used to determine the distribution and central region for each of the main pollen taxa identified. Picea pollen at abundance levels above 30% indicated the existence of local spruce forests, as observed in the Tianshan and Altai mountains’ conifer forests. A considerable amount of Betula pollen was observed in the intrazonal vegetation dominated by Betula, such as wetlands and river valleys, indicating the distribution of birch forests in the local vegetation. The pollen taxa of Ephedra, Chenopodiaceae, and Artemisia was over-represented across all investigated areas. These data may improve the accuracy and reliability of vegetation and climate reconstructions based on pollen data; furthermore, our information provides a framework for predicting future environmental trends.

ЗЕМЛЕПОЛЬЗОВАНИЕ И ВОЗМОЖНОСТИ РЕГУЛИРОВАНИЯ АНТРОПОГЕННОЙ НАГРУЗКИ НА ГОРНЫЕ ЛАНДШАФТЫ СЕВЕРНОГО МАКРОСКЛОНА БОЛЬШОГО КАВКАЗА (На примере долины р. Карасу)

Aim. The basis for the optimal development of mountain regions is the regulation of anthropogenic impact on natural land-scapes. The purpose of the study is to assess the state of natural landscapes of the highlands of the Central Caucasus and substantiate effective mechanisms that regulate economic activity in territories adjacent to nature conservation ones. On the example of the Karasu river valley, which is representative of the Northern macro slope of the Greater Caucasus, analyzes the features of anthropogenic impact in the form of recreation, tourism and grazing. Research methods. The key method of this research is the making of maps showing the landscape structure of the area under consideration, the spatial features of the location of exogenous processes and types of nature management. Using the above maps, the features of the geological and geomorphological basis and landscape structure of the Karasu river valley were identified, the features of modern nature management were characterized, the consequences of anthropogenic impact on natural landscapes were assessed, and the management approach were formulated to reduce the negative impact on the nature of mountain areas. To assess the land cover, high-resolution satellite images were used, according to which the difference vegetation in-dex was calculated, which most clearly distinguishes the main types of the cover. Results. Within the boundaries of the study area, the role of shrub-meadow vegetation of the subalpine zone, which performs a water-retaining function, is especially significant. The destruction of land cover due to overgrazing, the construction of capital facilities, and other types of economic activity without the necessary protective engineering and land reclamation measures favors the development of destructive exogenous processes. The border of the reserved and non-reserved territories is smooth (not sharp). Conclusions. The gradual transition from landscapes with a reserved regime to landscapes with different uses requires a revision of the concept of nature protection in the direction of developing measures on the principle of “protection in use.” Particular attention should be paid to the conservation of sub-alpine meadows, alpine meadows and wastelands, bog complexes, which have a high species diversity, the presence of endemic species and are small in area. The main environmental measures for these communities are state monitoring and the maximum possible reduction in anthropogenic impact.