Valley Forest Research Articles

Deciphering the vectors: Unveiling the local dispersal of Litylenchus crenatae ssp. mccannii in the American beech (Fagus grandifolia) forest ecosystem.

Beech leaf disease (BLD), caused by the Litylenchus crenatae ssp. mccannii (Lcm) nematode, is an emerging threat to beech trees. This disease is characterized by distinct leaf symptoms, including leaf interveinal banding and thickened leaf texture, which leads to eventual tree mortality. Understanding Lcm dispersal mechanism(s) is crucial for managing BLD, yet these remain largely unknown, posing a major barrier to its effective management. This study represents a pioneering investigation into the abiotic and biotic vectors that potentially contribute to the local dispersal of Lcm in natural American beech (Fagus grandifolia) forest systems in the Northeastern United States. An experiment was set up in Stone Valley Forest, Pennsylvania (PA), using four funnel stands placed at variable distances from naturally BLD-infected beech trees. This approach enabled the recovery of active Lcm nematodes from each funnel, demonstrating their ability to naturally disperse at least 11.74 m from the nearest BLD-infected tree. The findings highlight the role of abiotic factors involved in the dispersal dynamics of Lcm, especially wind and humidity, as indicated by a generalized linear model. The current study also uncovered the incidental association of Lcm with other organisms beneath the canopy of BLD trees, including spiderwebs and caterpillars. To our knowledge, this is the first study to document the potential vectors involved in the local dispersal of Lcm, offering valuable information for the biology of this nematode, as well as insight into the development of effective BLD management strategies. The findings contribute to broader efforts in advancing the understanding of the local spread of BLD, highlighting the complex interplay of abiotic and biotic factors in this disease dispersal.

Scale-dependent effects of vegetation attributes and soil fertility on productivity in two temperate forests in Northeast China

Forests are rich in biodiversity and high in productivity, and understanding the relationship between biodiversity and productivity is critical to the sustainable management of forest ecosystems. Although biodiversity and other factors contribute to forest productivity to varying degrees, it is unclear whether spatial scale (or plot size) influences this relationship. In this study, we analyzed the impacts of biodiversity, trait composition, structural attributes, and soil fertility on forest productivity at three scales in two temperate old-growth forests. We found that structural attributes, including basal area and stand density, were positively correlated with productivity and were consistently the strongest drivers of productivity changes in both forest types. Trait composition had a weak direct positive correlation with productivity. Soil nitrogen had positive effects on productivity, and soil moisture content had negative effects, both of which increased with increasing plot size. Different results for the effect of biodiversity on productivity were found between the two forests. In the mixed broadleaved-Korean pine forest, diversity correlated positively with productivity, and the strength of the relationship increased with increasing plot size. In contrast, in the spruce-fir valley forest, diversity had a direct positive correlation with productivity at 10 m × 10 m, no significant effect at 20 m × 20 m, and a negative correlation at 30 m × 30 m. Our results suggest that the contribution of vegetation attributes and soil fertility to forest productivity varies with scale. Despite the fact that both the niche complementarity hypothesis and the mass ratio hypothesis act simultaneously in forests, they have limited effects on productivity. Stand structural attributes play a key role in elucidating the biodiversity-productivity relationships, and they may serve as a more significant regulator of forest productivity than diversity. At the same time, the role of soil fertility in regulating productivity cannot be ignored.

Unique Plant Resources and Distribution Patterns in the Valley Forest of the Irtysh River Basin.

The river valley forests of the Irtysh River Basin are a germplasm bank of Salicaceae species and rare plant resources in China, and the distribution varies with the river and is highly distinctive. However, there is a dearth of systematic research on the characteristics of plant resources. In this study, a comprehensive investigation was conducted in the trunk stream and six tributaries with valley forest distribution in the Irtysh River Basin, and 244 quadrats were set up. The analysis focused on the composition of the flora and resource characteristics. The results reveal the following: (1) The valley forests of the Irtysh River Basin contain 256 species of plants belonging to 57 families and 178 genera, among which 19 species of trees, 23 species of shrubs, and 214 species of herbs were investigated. (2) Among the identified species, 226 (88.67%) were recognized as resource plants, with medicinal plants being the most abundant (176 species, 68.75% of the total). (3) The distribution patterns of trees, shrubs, and herbs of each resource type vary across rivers. Elevation drop, river length, and river distance all significantly affect the number of specie. This study elucidated the current status and distributional characteristics of plant resources in the valley forests of the Irtysh River Basin, which is essential for both biodiversity conservation and sustainable resource utilization.

Spatial Distribution Patterns and Influencing Factors of Dominant Species in Plain Valley Forests of the Irtysh River Basin

The Irtysh River, which stretches for 633 km, is the second longest river in Xinjiang. The valley forests within its basin are unique forest resources that exhibit crucial ecological functions and form an integral part of China’s “Three North” Shelterbelt Forest Project. However, previous studies mainly focused on individual tributaries or main streams, lacking comprehensive research on the overall river and valley forest resources and their ecological functions. To address this research gap based on comprehensive investigations, this study analyzed the dominant species composition, spatial distribution patterns, and influencing factors of valley forests across various branches of the Irtysh River basin plain. The results revealed the presence of 10 local tree species in the area, with Populus laurifolia, Populus alba, Salix alba, and Betula pendula as the dominant species. However, seedling regeneration was relatively weak. P. laurifolia, P. alba, and S. alba were widely distributed across tributaries and main streams, whereas B. pendula was primarily found in the tributaries. The four dominant species exhibited distinct clustering patterns. The concentration intensity of these dominant species in the main stream of the Irtysh River basin was significantly higher than those in other tributaries, with P. laurifolia showing a lower concentration intensity across the entire basin than the other dominant species. Negative density dependence was the primary biological factor influencing species aggregation intensity, with significant positive effects on P. alba and S. alba and significant negative effects on B. pendula. Among the abiotic factors, elevation had a significant positive effect on the aggregation intensities of P. alba, S. alba, and B. pendula, indicating that these species tend to aggregate more densely at higher elevations. Conversely, slope had a significant negative impact on the aggregation intensities of P. laurifolia, P. alba, and S. alba, suggesting that increasing slope steepness leads to a decrease in the clustering of these species. Similarly, the distance from the river channel had a significant negative effect on the aggregation intensities of S. alba and B. pendula, implying that as the distance from the river increases, the clustering patterns of these species become less pronounced. This study aimed to detail the current state of valley forest resources and their ecological functions, thereby laying a foundation for their effective protection.

Patterns of native and invasive lianas of Virginia's Ridge and Valley forests in relation to land use history

Patterns of native and invasive lianas of Virginia's Ridge and Valley forests in relation to land use history

Inter‐ and intraspecific stomatal morphological traits vary in response to topographic habitat changes

AbstractQuestionsStomata can reflect the plant's adaptation to environmental changes. However, the variation patterns of stomatal traits across different habitats and their relationships with environmental drivers are still poorly understood. Here, we assessed the extent of interspecific and intraspecific variation in stomatal traits in two typical riparian forests, and investigated how stomatal traits adapt to habitat change as well as trait–environment relationships.LocationThe Irtysh River Basin in China.MethodsWe measured the stomatal density (SD), stomatal size (SS), and stomatal relative area (SRA) of dominant plant species from two riparian forests: (1) a riparian forest in the valley and (2) a riparian forest in the pediment plain. We analyzed the stomatal trait variation patterns of dominant plant species in different habitats. We then quantified the magnitude of intraspecific and interspecific stomatal trait variability and evaluated the relationships between stomatal traits and environmental factors.ResultsWe found that SD and SRA were significantly higher in pediment plain forests than in valley forests, whereas SS was not significantly different between these habitats. The SD and SRA of trees in pediment plain forests were significantly higher than those in valley forests, whereas there were no significant differences in understory plants between habitats. The interspecific variation in each stomatal trait was significantly higher than the intraspecific variation. Stomatal traits were more related to the soil environment than to climatic factors.ConclusionsResponse strategies of stomatal traits to habitat changes differed between species and functional groups, and trait–environment relationships depended on the habitat type of the riparian forest. Our analysis of stomata trait variation implies adaptive strategies in species of natural riparian forest. Insights into trait–environment relationships could be used to predict carbon and water cycling, and vegetation changes in riparian forests of arid regions, especially in the context of climate change.

Genetic Diversity of Dominant Species Betula pendula in River Valley Forests in the Irtysh River Basin and Sustainable Conservation Measures for the Future

Biodiversity is the basis for the maintenance and functioning of ecosystems. Genetic diversity is at the heart of biodiversity, and therefore an understanding of the current state of plant genetic diversity can contribute to the future provision of sustainable ecological values and services by ecosystems. This study was conducted in the Irtysh River basin (five tributaries) with the dominant species of river valley forests, Betula pendula. Sampling points were set up at approximately 10 km intervals within each tributary using a random sampling method for genetic diversity studies based on chloroplast microsatellite molecular markers. The results indicated that (1) nine alleles were identified in 198 samples. The genetic diversity of Betula pendula was relatively rich in all tributaries (I = 0.216~0.546); genetic diversity was significantly higher in the downstream area of the basin than in the midstream and upstream areas of the basin. Genetic differentiation was at a low level in the tributaries except for the Berezek River, where genetic differentiation was high. (2) Genetic variation was mainly derived from within populations, accounting for 62% of the total genetic variation. The genetic distance was significantly positively correlated with the geographical distance (p < 0.05). The Betula pendula population structure was divided into two major groups. (3) Twelve haplotypes were identified in the basin. The dominant haplotypes in the upper tributaries were H2 and H4, while in the lower tributaries these were H1 and H3. Therefore, this paper suggests the future establishment of a germplasm resource bank for populations of the Berezek River, and the implementation of priority conservation measures for the downstream populations with higher genetic diversity, so as to realize the sustainable ecological value of the valley forests of the Betula pendula.

Empirical Study on the Impact of Different Types of Forest Environments in Wuyishan National Park on Public Physiological and Psychological Health

Amidst the challenges of global environmental change and urbanization, the salutary effects of natural environments on public health are increasingly being recognized. This study investigates the specific effects of varied forest environments in China’s Wuyishan National Park on physiological and psychological health. Eight distinct forest environments were carefully selected, and a repeated-measures ANOVA approach was used to evaluate 41 participants over three days. Physiological assessments included Heart Rate Variability, Skin Conductance Level, and surface Electromyography, complemented by psychological evaluations using the Profile of Mood States. The key findings include the following: (1) Notable variations in physiological indicators were observed among different forest types. In valley tea gardens and broadleaf forest streamside, significant changes in heart rate indicators highlighted the influence of these settings on autonomic nervous activities. Skin Conductance Level and surface Electromyography also indicated varying emotional arousal and pleasure across the forests. The mixed broadleaf and coniferous forest valley, along with the rock-bedded streamscape, elicited emotions of low arousal but high pleasure, inducing feelings of calmness and pleasure. The valley’s tea gardens were associated with low arousal and pleasure, suggesting tranquility without positive emotional induction, while the broadleaf ridge forest induced high arousal and pleasure, reflecting an exciting and joyful environment. (2) The study found that different forest environments had a notable impact on participants’ mood states, indicating reductions in tension, anger, fatigue, and depression, along with an increase in vigor levels. In summary, forest environments offer unique psychological and physiological health benefits compared to urban settings. These findings underscore the importance of integrating forest environments into urban development and public health frameworks, and the need to further explore their impact on the health of diverse populations.

Community structure and characteristics of plain valley forests in main tributaries of Ertix River Basin, China

Community structure and characteristics of plain valley forests in main tributaries of Ertix River Basin, China

Another step through the crux: a new microendemic rock-dwelling Paroedura (Squamata, Gekkonidae) from south-central Madagascar.

Using an integrative taxonomic approach including genetic and morphological data, we formally describe a new microendemic gecko species belonging to the Paroedurabastardi clade, previously referred to as P.bastardi D. We name this taxon currently known from Anja Reserve and Tsaranoro Valley Forest (south-central Madagascar), as P.manongavatosp. nov. The new species differs from other species of the P.bastardi clade by ≥ 12.4% uncorrected p-distance at the mitochondrial 16S rRNA gene and it forms a monophyletic group in the COI mtDNA phylogenetic tree. It lacks haplotype sharing at the nuclear KIAA1239 and CMOS genes with the other species of the same complex, including the syntopic P.rennerae. Given its limited extent of occurrence and high levels of habitat fragmentation linked to forest clearances and fires, we propose the IUCN Red List Category of Critically Endangered, based on the B1ab(iii) criterion. The conservation value of Anja Reserve and Tsaranoro Valley Forest is remarkable. Preserving the remaining deciduous forest habitat is of paramount importance to protect these narrow-range reptile species.

Desertification induced changes in soil bacterial and fungal diversity and community structure in a dry-hot valley forest

Increase in aridity is a global phenomenon due to climate change. Understanding soil microbial communities' response to aridity induced desertification is essential to predict the regulation of microbial processes under climate change and to develop feasible restoration plans. Therefore, to elucidate desertification effects, we investigated the changes in soil properties and, shifts and drivers of soil microbial diversity and community composition of a dry-hot valley-based Pinus densata forest located in south-east Tibetan Plateau of China. Amplicon sequencing of bacterial and fungal communities were used to determine soil bacterial and fungal community composition and diversity patterns. The results revealed that soil bacterial and fungal alpha-diversities were lower in desertified P. densata forest soils. Soil total carbon content (TC) was the major predictor of bacterial Pielou index. Whereas fungal Chao 1 and Simpson diversity indices were mainly influenced by total nitrogen contents (TN) of the soil. Differential response between soil bacterial and fungal communities' structures were observed between the desertified and non-desertified soils. Soil pH mainly regulated the overall microbial community structures in addition to TC determining bacterial and TN determining fungal community structures, respectively. Changes in the relative abundance of bacterial phylum Chloroflexi and Actinobacteria, and the ratio of fungal phylum Ascomycota/Basidiomycota were the indicators of intensity of soil desertification in the studied forests. The relative abundance of pathogenic microbial communities in soils was more in desertified soils in comparison to the non-desertified soils of P. densata forests, such as the bacterial genus Conexibacter and fungal genera Penicillium and Ilyonectria. This study evidences the differential response of soil bacterial and fungal communities to changes in soil biotic and abiotic properties indicating differential adaptive mechanism in a forest ecosystem currently experiencing adverse effects of rapid desertification.

Овсянка-ремез Ocyrisrusticus на территории Вишерского и Норского заповедников

The Information about the state and the dynamics of the number of the local nesting population of the Rustic bunting in the Visherky strict nature reserve of the Perm Region is given. The average population density of Ocyris rusticuson the territory of the strict nature reserve in the nesting period, according to data until 2014, is: 1.5±1.2 pairs/km2in mountain taiga forests, and 1.4±1.1 pairs/km2in valley forests. A comparison is made with the Norsky strict nature reserve of the Amur Region, where the species occurs on migration, and the dynamics of the number of migratory birds is analyzed. The validity of including the species in the Red Books of the Russian Federation and regions is discussed.

Ecohydrological Variation and Multi-Objective Ecological Water Demand of the Irtysh River Basin

Hydrological processes regulate the ecological processes of a basin. Climate change and anthropological activities lead to changes in the natural hydrological process of rivers, whereas variations in hydrological processes can disrupt the stability of ecosystems, resulting in various ecological challenges. Quantitative evaluation of ecological water demand and its key components can play a key role in the sustainable development of ecosystems. The studies of ecohydrological variation and multi-objective ecological water demand are of great significance for ecological protection and remediation due to the unique characteristics of each river basin and diverse ecological protection objectives. This study identified ecohydrological variation in ecosystems, focusing on the Irtysh River Basin as a case study, and improved methods for ecological water demand of valley forests and grasslands in terrestrial ecosystems and for the ecological water level of lake ecosystems. The results demonstrated that: (1) a drastic decrease in the annual average river flow of the basin and significant changes in ecohydrological characteristics can lead to reduced biomass; (2) the ecological water demand of valley forests and grasslands during the critical ecological stage (April–September) was 521 million m³, with 52.4% of total demand occurring in June and July. The minimum ecological water levels of the Burultokay and Jili lakes were 478.66 m and 480.66 m, whereas the maximum levels were 482.80 m and 483.20 m, respectively; (3) ecological regulation based on catchwork irrigation technology can create hydrological processes that meet the water demands of valley forests and grasslands and achieve remediation of the terrestrial ecosystem. The ecological water levels and the ecosystem balance of the Burultokay and Jili lakes can be maintained by optimizing the replenishment flow from the Irtysh River to the Burultokay Lake under different precipitation levels. This study can act as a reference for the ecological protection and remediation of the Irtysh River Basin and similar ecosystems globally.

Reservoir Regulation for Ecological Protection and Remediation: A Case Study of the Irtysh River Basin, China.

Hydrological processes play a key role in ecosystem stability in arid regions. The operation of water conservancy projects leads to changes in the natural hydrological processes, thereby damaging the ecosystem balance. Ecological regulation is an effective non-engineering measure to relieve the influence of water conservancy projects on ecosystems. However, there are still some problems, such as an insufficient understanding of hydraulic processes and difficulty evaluating the application effects. In this study, the theory of ecological reservoir regulation coupled with hydrological and ecological processes was examined and ecological protection and remediation were investigated using the valley forests and grasslands in the Irtysh River Basin as a case study. The results demonstrated that (1) to meet the demand of the hydrological processes in the valley forests and grasslands, in terms of ecological regulation, the peak flow and flood peak duration of the reservoir, named 635, in the Irtysh River Basin should be 1000 m3 s−1 and 168 h, respectively, and the total water volume of ecological regulation should be 605 million m³. Ecological regulation can guarantee that the floodplain range reaches 64.3% of the core area of ecological regulation and the inundation duration in most areas is between 4–8 d; (2) an insufficient ecological water supply would seriously affect the inundation effects. The inundation areas were reduced by 2.8, 5.1, 10.3, and 19.3%, respectively, under the four insufficient ecological water supply conditions (528, 482, 398, and 301 million m3), and the inundation duration showed a general decreasing trend; (3) the construction of ecological sluices and the optimization of the reservoir regulation rules could effectively relieve the influences of an insufficient ecological water supply. At water supply volumes of 528 and 482 million m3, the regulation rules should assign priority to the flood peak flow; at water supply volumes of 398 and 301 million m3, the regulation rules should assign priority to the flood peak duration. Consequently, this study provides a reference for ecological protection in arid regions and the optimization of ecological regulation theories.

Population density and distribution of common warthog (Phacochoerus africanusGmelin, 1788) in Dabena Valley Forest, Western Ethiopia

AbstractA study about the spatial distribution and density of common warthog (Phacochoerus africanus) was conducted in two focal areas in Dabena Valley Forest, Western Ethiopia, from May 2016 to June 2018. These were Gassi Controlled Area (GCHA) in the southwestern part and Haro Aba Diko Controlled Hunting Area (HADCHA) in the northeastern part of the Valley. Population abundance and densities were analysed using distance sampling method. A total of 246 and 652 warthogs were counted in GCHA and HADCHA, respectively. The two study areas were significantly different during the wet season and during the dry season in the number of common warthog population per transect. During the dry season, HADCHA possessed more mean of cluster density (5.18/km2) than the GCHA (2.37/km2). Common warthog encounter rate ranged from 1.1 to 3.73/km during the wet season in both study areas. The two study areas did not show significant variation (χ2 = 0.188,df = 1,p = 0.05) in the clusters of common warthog sightings. A high number of common warthog population are threatened by increasing anthropogenic activities. Common warthog's natural habitats and their buffer zones should be properly monitored: Cattle grazing and human encroachment should be prohibited.

Population size and habitat preference of the Omo River guereza (Colobus guereza guereza) in a multi-habitat matrix in the central highlands of Ethiopia.

Given the current rate of habitat degradation and loss in the tropics, data on primate population densities and habitat use are indispensable for assessing conservation status and designing feasible management plans for primates. The Omo River guereza (Colobus guereza guereza) is a subspecies of the eastern black-and-white colobus monkey endemic to the western Rift Valley forests of Ethiopia. Their restricted distribution along with habitat loss and hunting within their range render them vulnerable to local extirpation and extinction. Furthermore, there are no published data available on the population status and habitat use patterns of the Omo River guereza. We therefore aimed to assess the population size of Omo River guerezas in different habitats (Erica-Juniperus mixed forest, mixed plantation forest, undisturbed natural forest, disturbed natural forest) using transect surveys at Wof-Washa Natural State Forest (WWNSF) in central Ethiopia. Our surveys covered a cumulative distance of 88.5km in four different habitats, during which we recorded a total of 140 Omo River guereza groups. The average group density was 14.3 groups/km2, average individual density was 94.4 individuals/km2, and we estimated the total population size within WWNSF to be 2549 individuals. The sex ratio of the population was split evenly between males and females, though the age classes skewed strongly towards adults. Of the habitats surveyed, the highest group encounter rate (1.83 groups/km) occurred in the disturbed natural forest. However, the highest individual density (110.1 individuals/km2) was recorded in undisturbed natural forest. Still, sizable densities (group and individual) were recorded in three of the disturbed habitats (disturbed natural forest, mixed plantation forest, and to a lesser extent Erica-Juniperus mixed forest). Our study offers the first baseline information with which to compare future population density estimates and habitat use in the range of Omo River guerezas.

Мониторинг изменения состояния растительного покрова на участке трассы трубопровода проекта «Сахалин-2» по данным космических съемок

The construction of underground main oil and gas pipelines leads to significant changes in natural landscapes. During the construction of main pipelines, felling of forest massifs is carried out. There is a high probability of the development of exogenous geological processes in the presence of mountain-ous relief and abundant precipitation. Revegetation control of pipelines is very important, and special attention should be paid to control when laying pipelines through specially protected natural areas. The article presents the results of assessing the nature and dynamics of the restoration of the vegetation cover on the section of the Sakhalin-2 gas pipeline in the Dolinsky sanctuary based on the results of calculating NDVI from satellite images using geoinformation technologies, and checking the results by field research data. The purpose of the research is to analyze the change in the state of the vegetation cover, determined by the volume of phytomass (calculation by NDVI) based on space monitoring da-ta. Methods: interpretation and analysis of space images from spacecraft of the Landsat and Sentinel-2 family for the period from 2001 to 2021, geoinformation mapping of changes in the state of vegetation on the ArcGIS platform. Results: 5 stages of change in the state of the vegetation cover in the studied time interval were identified. The results show revegetation 10 years after the completion of the pipeline. Good restoration of valley forests and grass cover was noted. Sparse vegetation is com-mon in sections of the pipeline where biological reclamation has not been carried out. As result of work carried out, an increase in NDVI revealed, and, consequently, the presence of good conditions for the growth of plant communities, typical for the investigated section of the pipeline of the Sakhalin-2 project after completion of construction work.

The flora of pine forests of the vicinity of Hrafske village (Vovchansk District, Kharkiv Region)

The article presents the results of a study of the flora of pine forests in the vicinities of the villages Hrafske, Verkhnia Pysarivka, and Symonivka of the Vovchansk District of the Kharkiv Region. The flora of the investigated area includes at least 120 species of vascular plants of 47 families, five classes, and four divisions. The richest in the flora are the families Asteraceae (22 species; 18.3%), Poaceae (13 species; 10.8%), and Caryophyllaceae (10 species; 8.3%) that are characteristic of the pine forests of the Kharkiv Region. The presence of Crassulaceae (5 species; 4.2%) at the fifth position in the spectrum of dominating families is due to anthropogenic impact on the vegetation of the study area. Analysis of the flora ecological structure by three main abiotic factors (soil water regime, total salt regime, and light) has shown the typical conditions of the valley forests of the Kharkiv Region with a predominance of mesophytic and submesophytic (84 species; 70%), semieutrophic (64 species; 52.9%) and subheliophytic (88 species; 72.7%) groups of plants. In the coenotic structure of the flora of studied forests, the forest (38 species; 31.4%) and ruderal (37 species; 30.6%) fractions were the leading ones, while the third position was occupied by the psammophytic species (22; 18.2%). A high number of weeds in the flora composition is explained by urbanization. Fractional analysis of the flora has shown a predominance of native species (90; 75%), mainly apophytes (47; 39.2%), adapted to growing in disturbed habitats. The adventive fraction includes 30 species (25%), among which kenophytes and xenophytes predominate. Localities of three rare species (Dryopteris carthusiana (Vill.) H.P. Fuch, Jurinea charkoviensis Klok., and Viburnum opulus (L.) Opiz.) were identified, which indicated conservation value of the study area. An index of the flora synanthropization (64.5%) is quite high due to ruderal species adapted to disturbed habitats. The studied valley forests are under anthropic pressure caused by nearby settlements via littering and deforestation, which results in flora impoverishment and the spread of alien plant species. Therefore, the forests in question require further monitoring.

Water vole (Arvicola amphibious) as an object of long-term biomonitoring in a floodplain area (Western Siberia, Russia)

The paper is devoted to the dynamics of the water vole population in the conditions of total deforestation of valley forests and their subsequent restoration. We analyzed the relative population of small mammals in the typical biotopes in the Tom River basin (Western Siberia) on the border of the forest-steppe and taiga zones. From 1978 to 2019, 1,139 water voles Arvicola amphibius (Linnaeus, 1758) (synonym of A. terrestris) were caught with 50-meter trapping grooves; for 788 individuals we assessed the condition of non-metric features (phenes) of the skull. It was found that changes in the population level are non-cyclical, while against the background of a generally low occurrence of the species in the region, the population level increased tenfold in some years. It was shown that such episodic population surges can significantly impact the structure of the community of small mammals. In the valley of the Tom River, the water vole prefers inhabit wet meadows and ecotone areas between the meadow and the dark coniferous taiga forest. During the years of population surges, the water vole intensely occupies new nesting sites due to the dispersal activity of young animals but at the same time retains the original biotopic preferences. Dispersal of the species takes place in waterlogged wetlands. Most of the animals caught during the peak of their numbers were young animals of late broods born from overwintered individuals. The conducted phenetic analysis revealed the heterogeneity of young animals during the population surge, which allowed us to assume the participation of several populations in the formation of the peak. In the final surge year, the surge was characterized by an extremely low percentage of participation in the breeding of young females and the appearance of a large number of weakened animals, which led to crisis in the species population and the disappearance of the water vole from the captures. The research shows that one cannot predict the success of this process at the current stage; therefore, after flooding, it is necessary to continue monitoring.

Water vole (Arvicola amphibius) as an object of long-term biomonitoring in a floodplain area (Western Siberia, Russia)

The paper is devoted to the dynamics of the water vole population in the conditions of total deforestation of valley forests and their subsequent restoration. We analyzed the relative population of small mammals in the typical biotopes in the Tom River basin (Western Siberia) on the border of the forest-steppe and taiga zones. From 1978 to 2019, 1,139 water voles Arvicola amphibius (Linnaeus, 1758) (synonym of A. terrestris) were caught with 50-meter trapping grooves; for 788 individuals we assessed the condition of non-metric features (phenes) of the skull. It was found that changes in the population level are non-cyclical, while against the background of a generally low occurrence of the species in the region, the population level increased tenfold in some years. It was shown that such episodic population surges can significantly impact the structure of the community of small mammals. In the valley of the Tom River, the water vole prefers inhabit wet meadows and ecotone areas between the meadow and the dark coniferous taiga forest. During the years of population surges, the water vole intensely occupies new nesting sites due to the dispersal activity of young animals but at the same time retains the original biotopic preferences. Dispersal of the species takes place in waterlogged wetlands. Most of the animals caught during the peak of their numbers were young animals of late broods born from overwintered individuals. The conducted phenetic analysis revealed the heterogeneity of young animals during the population surge, which allowed us to assume the participation of several populations in the formation of the peak. In the final surge year, the surge was characterized by an extremely low percentage of participation in the breeding of young females and the appearance of a large number of weakened animals, which led to crisis in the species population and the disappearance of the water vole from the captures. The research shows that one cannot predict the success of this process at the current stage; therefore, after flooding, it is necessary to continue monitoring.