Deschampsia Cespitosa Research Articles

Mixed-cultivation grasslands enhance runoff generation and reduce soil loss in the restoration of degraded alpine hillsides

Abstract. Vegetation restoration is among the most effective measures for controlling runoff and soil erosion resulting from human activities. Nevertheless, few studies have been undertaken to analyze the effects of grassland restoration on maintaining local runoff, especially on alpine degraded hillsides where mixed-cultivation grasslands predominate. In this research, runoff plots were established to investigate the impact of three mixed-cultivation grasslands, each sowing two grass species per plot on a 20° slope: Deschampsia cespitosa and Elymus nutans (DE), Poa pratensis L. cv. Qinghai and Elymus nutans (PE), and Poa pratensis L. cv. Qinghai and Deschampsia cespitosa (PD). The activation and volume of surface runoff and the magnitude of soil loss on alpine degraded hillsides over 3 years (2019, 2020, and 2022) were assessed. A severely degraded meadow (SDM) plot was used as a control. The findings indicated that mixed-cultivation grasslands can effectively maintain runoff and reduce soil loss as planting age increases. Between 2019 and 2022, the values of the average runoff depth for DE, PE, PD, and SDM were 0.47, 0.55, 0.45, and 0.27 mm, respectively. Despite the increase in runoff, grassland restoration favored soil conservation: the net soil losses per unit area of SDM were 1.4, 1.3, and 1.9 times greater than those in DE, PE, and PD, respectively. The key factors affecting soil loss and runoff were rainfall amount, duration, and intensity (60 min intensity). We conclude that the results of this study can serve as scientific guides to formulate efficient policy decisions for planning the most effective vegetation restoration in severely degraded hillside alpine meadows. To improve the effectiveness of grassland restoration, we suggest that protective measures should be prioritized during the initial planting stage of cultivated grasslands.

Ornamental Grasses Tolerate Cyclical Flood, Drought, and Submergence During Stormwater Management, but Conditions and Survival Vary by Species

Perennial ornamental grasses are often recommended for rain gardens, but few data support their use. We conducted two experiments to evaluate the ability of ornamental grass cultivars to grow while subjected to cyclical flooding, submergence, and drought typical of rain gardens. Our objectives were to determine the effects of cyclical flood and drought (Expt. 1) and submergence depth and duration (Expt. 2) on grass growth and survival. Seven cultivars were evaluated during greenhouse trials, including Pixie Fountain tufted hairgrass [Deschampsia cespitosa (L.) P. Beauv.], Northwind switchgrass (Panicum virgatum L.), Red October big bluestem (Andropogon gerardii Vitman), Purpurascens Chinese silvergrass (Miscanthus sinensis Andersson), Blue Heaven® little bluestem [Schizachyrium scoparium (Michx.) Nash], Blonde Ambition blue grama grass [Bouteloua gracilis (Kunth) Lag. ex Griffiths], and Karl Foerster feather reed grass [Calamagrostis ×acutiflora (Schrad.) DC]. During Expt. 1, grasses underwent four cycles of flooding duration (2 days or 7 days) followed by drought (drying to volumetric soil water contents of 0.14 or 0.07 cm3·cm−3). During Expt. 2, grasses were cyclically submerged at 15 or 30 cm above the soil surface for 2, 4, or 7 days, followed by floodwater removal and drainage for 2 days before being resubmerged. Cyclical submergence continued until the 7-day submergence treatments completed four cycles. Both experiments were replicated in a full factorial randomized complete block design. Controls were included in both experiments. Plants were measured to determine plant height, shoot count, visual damage rating, shoot dry weight, and root dry weight. Floodwater chemistry and soil reducing conditions were measured during Expt. 2. Chinese silvergrass and switchgrass survived cyclical soil flooding/drought and submergence for 7 days at a depth of 30 cm while maintaining acceptable foliar damage. All grasses survived cyclical flood and drought when the soil volumetric water content was maintained at 14%, suggesting they can withstand periodic soil flooding as long as the water is not too deep. As water depth and duration increased from 4 days to 7 days, little bluestem, blue grama grass, and feather reed grass experienced significant foliar damage. Tufted hair grass and big bluestem experienced significant foliar damage when submerged for 2 days. Our results showed that perennial ornamental grasses can tolerate cyclical flood and drought and periodic submergence, but that plant conditions and survival vary, which can inform strategic plant placement within rain gardens, bioretention basins, and other stormwater management systems.

Initial Litter Chemistry and UV Radiation Drive Chemical Divergence in Litter during Decomposition.

Litter's chemical complexity influences carbon (C) cycling during its decomposition. However, the chemical and microbial mechanisms underlying the divergence or convergence of chemical complexity under UV radiation remain poorly understood. Here, we conducted a 397-day field experiment using 13C cross-polarization magic-angle spinning nuclear magnetic resonance (13C-CPMAS NMR) to investigate the interactions among the initial chemistry, microbial communities, and UV radiation during decomposition. Our study found that the initial concentrations of O-substituted aromatic C, di-O-alkyl C, and O-alkyl C in Deschampsia caespitosa were higher than those in Kobresia tibetica. Litter's chemical composition exhibited divergent patterns based on the initial chemistry, UV radiation, and decay time. Specifically, D. caespitosa consistently displayed higher concentrations of di-O-alkyl C and O-alkyl C compared to K. tibetica, regardless of the UV exposure and decay time. Additionally, litter's chemical complexity was positively correlated with changes in the extracellular enzyme activities, particularly those involved in lignin, cellulose, and hemicellulose degradation, which accounted for 9%, 20%, and 4% of the variation in litter's chemical complexity, respectively. These findings highlighted the role of distinct microbial communities in decomposing different C components through catabolism, leading to chemical divergence in litter. During the early decomposition stages, oligotrophic Planctomycetes and Acidobacteria metabolized O-alkyl C and di-O-alkyl C under UV-blocking conditions. In contrast, copiotrophic Actinobacteria and Chytridiomycota utilized these components under UV radiation exposure, reflecting their ability to thrive under UV stress conditions due to their rapid growth strategies in environments rich in labile C. Our study revealed that the inherent differences in the initial O-alkyl C and di-O-alkyl C contributed to the chemical divergence, while UV radiation further influenced this divergence by shifting the microbial community composition from oligotrophic to copiotrophic species. Thus, differences in the initial litter chemistry, microbial community, and UV radiation affected the quantity and quality of plant-derived C during decomposition.

Assessment of the resistance of wild grasses in the northwestern region of the Russian Arctic to chloride salinization

Wild grasses are prevalent across various types of vegetation, playing a significant role in both natural ecosystems and human economic endeavors. The potential of using grasses to restore areas affected by tidal erosion and saline soils has not been fully investigated. A study was conducted to examine the impact of different levels of NaCl salinity (ranging from 20 to 200 mM) on seed germination and early growth of Agrostis capillaris L., Deschampsia cespitosa (L.) P. Beauv., Phalaris arundinacea L., and Phleum pratense L. These plants are commonly found in the Arctic region within the Belomorsky district of the Republic of Karelia. Through research, a direct connection was discovered between the germination of seeds and the growth of seedlings based on the salt levels in the root environment and the type of grass species present. In summary, all species successfully germinated at NaCl concentrations of 20–80 mM. However, germination rates decreased at 100 and 200 mM in most cases. When exposed to NaCl concentrations of 60 mM and higher, the growth of root and shoot in the grasses was slowed down to some extent (depending on the species), but not completely inhibited. Due to the resilience of wild grasses to cold temperatures, it is proposed that they could be used in the phytoremediation of Arctic areas with a salinity level of up to 100 mM (0.6 % salinity). An analysis of the data resulted in a ranking of grass species based on their salt resistance: P. pratense ˃A. capillaris ˃P. arundinacea ˃D. cespitosa.

Pharmacological correction of immunological disorders in perimenopausal women with recurrent epithelial cervical dysplasia associated with human papillomavirus infection

Despite the successes achieved in implementing screening programs and treating diseases caused by human papillomavirus (HPV) infection, the frequency of cervical intraepithelial neoplasia (CIN) of moderate and high grades associated with high-risk human papillomavirus (HR-HPV) remains between 9% to 21%. Vaginal dysbiosis and the development of immunodeficient states due to persistent HR-HPV infection require effective immunomodulatory and antiviral therapy before cervical surgery in perimenopausal women with recurrent CIN II.The objective: to evaluate the effectiveness of antiviral and immunomodulatory therapy by determining the state of vaginal biocenosis, immunological status and papillomavirus load of the cervical mucosa before surgical treatment in perimenopausal women with recurrent CIN II.Materials and methods. A prospective study was conducted on 98 women aged 40 to 55 years old, including 60 patients with morphologically verified recurrent CIN II associated with high-risk HPV, forming the main group. The control group comprised 38 women with negative HPV test results and without significant gynecological or somatic pathology. In the main group, a complex consisting of a blend of plant extracts of sod pike grass (Deschampsia caespitosa), ground cinquefoil grass (Calamagrostis epigeios), and echinacea purpurea grass (Echinaceae purpureae) was administered orally.Vaginal microbiota was assessed using Hey-Іson criteria, and immunological status was examined in patients using solid-phase enzyme-linked immunosorbent assay to determine IgG, IgM, IgA antibodies in serum and cervical mucus, levels of interleukin-1β (IL-1β), interferons alpha (IFN-α), gamma (IFN-γ), tumor necrosis factor alpha (TNF-α). Additionally, the DNA of high-risk HPV in cervical mucosa was quantitatively assessed using real-time PCR. The investigations were conducted before and after the applied therapy.Results. The investigation of vaginal content revealed the presence of bacterial vaginosis in 65.0% of patients in the main group, the frequency of which decreased by 2 times after treatment, with the number of women with an intermediate type of vaginal content increasing by 2.8 times (51.7%) and those with normal microbiota increasing by 2.5 times. Disruptions in cellular and humoral immunity systems were identified. After treatment, there was an increase in viral load in the significant «threshold» category (3–5 lg) by 1.25 times and in the «above threshold for progression» category (>5 lg) by 2.3 times, reflecting natural HPV clearance. No direct correlation was found between viral load activity and the degree of CIN or positive morphological changes regarding regression of cervical intraepithelial lesions.Conclusions. The use of a complex containing a blend of plant extracts of sod pike grass (Deschampsia caespitosa), ground cinquefoil grass (Calamagrostis epigeios), and echinacea purpurea grass (Echinacea purpureae) improves the state of vaginal biocenosis, indicators of cellular and humoral immunity, and promotes HPV elimination, it has adequate safety and tolerability, which determines the feasibility of its use in the complex treatment of cervical intraepithelial neoplasia at the preparatory stage before surgery and in the postoperative period to prevent complications and relapses.

Proline Metabolism in Response to Climate Extremes in Hairgrass

Hairgrass (Deschampsia caespitosa), a widely distributed grass species considered promising in the ecological restoration of degraded grassland in the Qinghai-Xizang Plateau, is likely to be subjected to frequent drought and waterlogging stress due to ongoing climate change, further aggravating the degradation of grassland in this region. However, whether it would acclimate to water stresses resulting from extreme climates remains unknown. Proline accumulation is a crucial metabolic response of plants to challenging environmental conditions. This study aims to investigate the changes in proline accumulation and key enzymes in hairgrass shoot and root tissues in response to distinct climate extremes including moderate drought, moderate waterlogging, and dry–wet variations over 28 days using a completely randomized block design. The proline accumulation, contribution of the glutamate and ornithine pathways, and key enzyme activities related to proline metabolism in shoot and root tissues were examined. The results showed that water stress led to proline accumulation in both shoot and root tissues of hairgrass, highlighting the importance of this osmoprotectant in mitigating the effects of environmental challenges. The differential accumulation of proline in shoots compared to roots suggests a strategic allocation of resources by the plant to cope with osmotic stress. Enzymatic activities related to proline metabolism, such as Δ1-pyrroline-5-carboxylate synthetase, ornithine aminotransferase, Δ1-pyrroline-5-carboxylate reductase, Δ1-pyrroline-5-carboxylate dehydrogenase, and proline dehydrogenase, further emphasize the dynamic regulation of proline levels in hairgrass under water stress conditions. These findings support the potential for enhancing the stress resistance of hairgrass through the genetic manipulation of proline biosynthesis and catabolism pathways.

Ecological and agricultural assessment of the state of forage lands of boreal river floodplains in the oil-producing region (case study in the floodplain of the Kolva River, Usinsky district, Komi Republic)

Floodplain forage lands of the Pechora basin (Usinsky district of the Komi Republic) are experiencing a complex anthropogenic impact associated with both agricultural activity and pollution with petroleum products coming with flood waters. An ecological and agricultural assessment of the soil-vegetation cover of the Kolva floodplain used as hayfield (right-bank part) and pasture (left-bank part) was carried out. Soil combinations of the main part of the surveyed floodplain include alluvial sod, sod-meadow and meadow soils. Morphological signs of gley formation in meadow soils are observed in the lower part of the soil profile and are expressed moderately. Soils are characterized generally by favorable agrochemical and morphological properties, with the exception of areas subjected to pasture digression. The vegetation cover of the central and near-river part of the floodplain massif of the right bank is mainly represented by legume-cereal-grass communities formed both in inter-ridge depressions and on flat ridges. On the high floodplain of the left bank, legume-cereal-grass meadows, grass-clover and tufted hairgrass meadows are common, horsetail–butterbur, clover-cereal and cereal communities are common in the near-river part of the left bank. Despite the relatively high productivity and the presence of valuable forage species of cereals and legumes, the qualitative characteristics of hay deviate from optimal ones due to the participation of low-nutritious, unattractive, weedy and poisonous species in the herbage. On the pasture, as a result of pasture digression, there is a decrease in species diversity with the dominance of tufted hairgrass and low-value species of various grasses. In the most disturbed areas, the total projective vegetation coverage is reduced to 50%. The soil cover of the studied territory of the Kolva floodplain is currently not contaminated with hydrocarbons, with the exception of a few spots of petroleum products with a total area of 6 m2. The effect of oil pollution on the vegetation cover of the Kolva floodplain is not manifested. Background values of the content of petroleum products in soils are slightly higher in the left-bank part compared to the right-bank part.

Активні компоненти флавоноїдного складу «Протефлазид» гальмують репродукцію вірусу грипу: можливі молекулярні мішені взаємодії

The search for substances possessing antiviral activities, in particular anti-influenza activity, is of importance for designing new drugs that may be effective in combating viral infections. The antiviral substances of the natural origin such as flavonoids and their derivatives are in the focus of numerous studies. The topical problem is the elucidation of the mechanisms of the interaction between flavonoid substances and the virus-specific targets in infected cells. Aim. To assess the activity of the flavonoid-enriched composition containing the biologically active substances of Proteflazidum against influenza virus in vitro and in vivo and to analyze in silico the putative interactions of the flavonoid components of the composition with PB2 subunit of viral RNA-polymerase. Methods. The anti-influenza effects of flavonoid-enriched composition prepared from the extracts of Deschampsia caespitosa L. and Calamagrostis epigeios L. were assessed in vitro in MDCK cells and in vivo in white outbred mice. Virion RNA was analyzed by RT-PCR with the primers detecting the transcripts of PB1 and PB2 subunits of viral RNA-polymerase and hemagglutinin. The potential interaction of the representative flavonoids of the composition with PB2 subunit of RNA-polymerase was analyzed in silico by molecular docking. Results. The composition under study inhibits effectively replication of А/FM/1/47 (H1N1) strain of influenza virus in vitro and protects the mice against flu infection both in therapeutic and preventive modes of its administration. According to the molecular docking findings, all three major flavonoid compounds of the composition, quercetin, luteolin, and apigenin, interact similarly with the PB2 domain of viral RNA-polymerase. Conclusions. The flavonoid composition containing the biologically active substances of Proteflazidum could be considered as the anti-flu drug with the PB2 subunit of viral RNA-polymerase being one of its potential molecular targets.

Effect of vegetation treatment and water stress on evapotranspiration in bioretention systems

Evapotranspiration is a key hydrological process for reducing stormwater runoff in bioretention systems, regardless of their physical configuration. Understanding the volumes of stormwater that can be returned to the atmosphere via evapotranspiration is, therefore, a key consideration in the design of any bioretention system. This study establishes the evapotranspiration dynamics of three common, structurally different, bioretention vegetation treatments (an Amenity Grass mix, and mono-cultures of Deschampsia cespitosa and Iris sibirica) compared with an un-vegetated control using lab-scale column experiments. Via continuous mass and moisture loss data, observed evapotranspiration rates were compared with those predicted by the FAO-56 Penman–Monteith model for five 14-day dry periods during Spring 2021, Summer 2021, and Spring 2022. Soil moisture reductions over the 14-day trials led to reduced rates of evapotranspiration. This necessitated the use of a soil moisture extraction function alongside a crop coefficient to represent actual evapotranspiration from FAO-56 Penman–Monteith reference evapotranspiration estimates. Crop coefficients (Kc) varied between 0.65 and 2.91, with a value of 1.0 identified as a recommended default value in the absence of treatment-specific empirical data. A continuous hydrological model with Kc=1.0 and a loading ratio of 10:1 showed that evapotranspiration could account for between 1 and 12% of the annual water budget for a bioretention system located in the UK and Ireland, increasing to a maximum of 35% when using the highest Kc observed (2.91).

Сосновые (Pinus sylvestris) леса и редколесья Северо-Западного Приладожья

Сосновые (Pinus sylvestris) леса и редколесья Северо-Западного Приладожья

Effects of Four Plant Growth Regulators on Photosynthesis and Yield of Deschampsia cespitosa

Effects of Four Plant Growth Regulators on Photosynthesis and Yield of Deschampsia cespitosa

Self-stabilization of Zn, Pb, Cd, and As in smelter-impacted organic-rich soil: The effect of hydrous Fe oxides and ZnCd sulfide coprecipitation

Soil constitutes a direct sink for elements mobilized due to mining and smelting activities. One of the desired pathways for reducing the bioavailability and toxicity of the contaminants is their transformation into sparingly soluble solid phases. Here, we report the formation of secondary mineral phases in extremely contaminated (up to 210 g Zn kg−1,102 g Pb kg−1, 5.68 g Cd kg−1, and 6.42 g As kg−1, respectively) organic-rich soil. Combining mineralogical techniques (SEM, XRD), a nonspecific sequential extraction (CISED) with Mössbauer and X-ray photoelectron (XPS) spectroscopies evidenced two poorly crystalline goethite components differing in crystallite size and As, Zn, Pb, Ca, Al, P substitutions and minor magnetite associated with plant roots (mainly Deschampsia caespitosa, Equisetum palustre, and Carex rostrate) directly below a layer of smelter-derived particles deposited into the soil. SEM was the only method that unambiguously documented the occurrence of ZnCd sulfide microsize aggregates incrusting plant roots and located in between the (hydrous) Fe oxides. Sequential extraction confirmed a complete As immobilization by goethite, while Cd forms a solid solution with ZnS and is lacking in the Fe hydroxides. The partitioning of Zn and Pb between the goethite and sulfide phases depends on soil water saturation. It is proposed that the coexistence of hydrous Fe oxides and nonferrous metal sulfides in the soil subsurface is possible because of redox heterogeneity of the rhizosphere and the decoupling of sulfur and iron cycles. Low mobility of biogenic sulfide ions and the protecting role of organic matter limits goethite sulfidation. The system remains active, adapting to the seasonally changeable plant roots ecology and fluctuations in water saturation. The obtained results are of value in remediation and managing strategies for contaminated soils and in reconstructing processes related to the formation and/or transformation of low-temperature sulfide deposits.

Mutual influence and conjugation between populations of alpine phytocoenoses in the Ukrainian Carpathians

The results of studies of association and mutual influence between populations of plant species of the most common alpine phytocenoses in the Ukrainian Carpathians are shown in this work. Considering objects of the research such species have been taken into account: Calamagrostis villosa, Campanula alpinа, Carex curvula, C. sempervirens, Deschampsia cespitosa, Festuca airoides, Helictotrichon versicolor, Hieracium alpinum, Homogyne alpina, Juncus trifidus, Leontodon croceus, Ligusticum mutellina, Loiseleuria procumbens, Nardus stricta, Potentilla aurea, Rhododendron myrtifolium, Sesleria coerulans, Soldanella hungarica, Vaccinium myrtillus, V. uliginosum, V. vitisidaea. Typical alpine groups, which are located in the highest mountain range of the Ukrainian Carpathians - Chornohora in the range of altitude from 1750 m above sea level to peaks over 2000 m, have been researched in this work. The method of studying interactions based on the definition of conjugate occurrence and association in the mutual arrangement of species is applied. All neighboring individuals have been counted around individuals of the active species. The obtained data has been compared with the population density of these species in the contours of the studied phytocenosis area. If neutral interactions between species is considered, then the percentage ratio of individuals in populations, established by the neighborhood, should correspond to their percentage the ratio established by the average density in the phytocenosis. Significant deviations indicate mutual influence or association between species The existence of active interaction between most plant species of the alpine zone was found. Dominants of alpine phytocenosis express neutral or weak interaction among themselves. Asectatory species are less competitive, but more flexible in terms of occupying free ecological niches. A negative interaction is often found between dominants and asectators. The nature of the interaction between the same species can vary in different coenoses. In most cases the presence of plant species, which are considered as positive neighbors, creates prerequisites for colonization of areas. In addition to dominants, it is advisable to use Helictotrichon versicolor in particular, which successfully occupies unsown areas and has a positive interaction with many plant species, in order to restore phytocenoses of the alpine belt, where the turf cover has been disturbed.

Seed nutrient is more stable than leaf in response to changing multiple resources in an alpine meadow

BackgroundIt has been long thought that nitrogen (N), phosphorus (P) concentrations and their ratios (N:P) in metabolically active or functional organs (i.e., leaves) are less responsive to environmental changes. Little attention, however, has been paid to the reproductive organs—seeds, while seeds may maintain their nutrients more stable for the evolutionary fitness of next generation.MethodsHere, we conducted a field experiment of N, P addition and drought in an alpine meadow, aiming to compare the difference of leaf and seed nutrients and stoichiometric ratios in response to these resource treatments and their interactions. Four dominant species were selected among grass and forb functional groups, including Elymus nutans, Deschampsia caespitosa, Artemisia roxburghiana and Polygonum viviparum.ResultsUnder natural conditions, leaf N and P concentrations were consistently lower than seed among species. However, leaf nutrients were much more sensitive than seed nutrients to N and P addition. Specifically, N or P addition accordingly increased leaf N or P concentration by 22.20–44.24% and 85.54–93.61%, while only enhanced seed N or P concentration by 5.15–17.20% and 15.17–32.72%, respectively. Leaf N or P concentration was significantly reduced by P or N addition, but seed nutrients remained unchanged. In contrast, drought did not change both organ nutrients. Similarly, nutrient addition and drought had synergistic interactions on leaf nutrients, but not on seed nutrients.ConclusionsThis study highlights that seed nutrient concentrations could be more stable than metabolically active leaf organ when facing multidimensional resource changes. This complements the traditional view on the ‘Stable Leaf Nutrient Hypothesis’ with the involvement of reproductive organs. The less responsiveness of seed nutrients suggests the adaptive strategy to ensure the success of next generations and long-term plant demographic stability.

Warming stabilizes alpine ecosystem facing extreme rainfall events by changing plant species composition

Abstract Climate warming and extreme climatic events are threatening ecosystem processes and functions. However, it remains unclear how climate warming changes ecosystem stability in facing extreme rainfall events. Here, we investigated the temporal stability of above‐ground net primary productivity (ANPP) in an alpine meadow via a 5‐year warming experiment, during which two flooding events occurred, in an alpine meadow. We first found that warming significantly increased the temporal stability of ANPP in facing flooding events by increasing resistance to and decreasing recovery from flooding events. Second, we found that warming shifted the plant community structure by increasing the dominance of grasses and reducing species richness and asynchrony. Last, we detected the higher temporal stability of ANPP under warming, which was mainly ascribed to the warming‐induced increase in dominant species stability (Deschampsia caespitosa). Synthesis. These findings indicate that climate warming may mitigate the shock of flooding events on the temporal stability of community productivity via altering plant community structure in alpine grasslands. Our study highlights that to buffer ecosystems from climatic extremes, we should focus on promoting the maintenance or selection of dominant species rather than only focusing on increasing species richness.

The analysis of the influence of grazing intensity on the diversity and abundance of plants and spiders (Arachnida: Araneae)

In restoration projects, low stock grazing has become a popular means of management. However, an accurate understanding of the effects of grazing on plants and spiders is often lacking. Although spiders and plants are not closely related evolutionarily or genetically, the relationship between them can be complex and diverse. Many species of spider build their webs or nests on plants, using the leaves, stems, or flowers as anchoring points. This provides them with protection from predators, access to prey and a stable habitat. On the other hand, spiders can provide a number of benefits to grassland ecosystems, such as helping to control populations of insects and other arthropods that can damage or consume grassland plants. This study addresses the effects of different grazing regimes on plant and spider diversity in siliceous grasslands. Plant and spider diversity was studied for four months in the Sharri Mountains (Kosovo) in order to determine the biodiversity in ungrazed, moderately grazed and overgrazed siliceuous grasslands. The responses of plant height, plant biomass, plant species diversity and spider species diversity to three grazing intensities at 12 sites were recorded. Vegetation structure (plant height and plant biomass) was significantly higher in ungrazed grasslands compared to grazed and overgrazed grasslands. This was not the case, however, for spider species richness and diversity, as these were higher in moderately grazed than ungrazed grassland. On overgrazed grasslands, spider diversity was extremely low, as only one species of spider (Pardosa saltuaria) was recorded. Plant and spider diversity increased in the following order: overgrazed grasslands < ungrazed grasslands < moderately grazed grasslands, in all the habitats studied. Different grazing intensities significantly affected the abundance of particular plants on siliceous grasslands, for example, Deschampsia cespitosa, one of the most dominant plants on siliceous grasslands had an abundance of 4.77% in ungrazed grasslands., but only 4.94% in moderately grazed grasslands and was absent in overgrazed grasslands. There were other species of plants that were most abundant in intensively grazed silicate grasslands. One of them was Nardus stricta, whose percentage in ungrazed, moderately grazed and overgrazed grasslands was characterized by a multiple exponential increase in % (s1 – ungrazed grasslands = 0.99%, s2 – moderately grazed grasslands = 1.25% and s3 – overgrazed grasslands = 10.50%). It is concluded that the intensity of grazing of natural grasslands directly affects biodiversity and that this information may be valuable for long-term management and conservation programs in similar habitats in SE Europe and beyond.

Towards reliable monitoring of grass species in nature conservation: Evaluation of the potential of UAV and PlanetScope multi-temporal data in the Central European tundra

The reliability of remote sensing technology is essential for its efficient operational applications in nature conservation practices. In our study, multi-temporal, multispectral, and hyperspectral data from an Unoccupied Aerial Vehicle (UAV) with a ground sampling distance (GSD) of 3 cm were applied to a permanent research plot (1 ha), while spaceborne PlanetScope multi-temporal data with GSD of 3 m were used for a wider area of 250 ha. The main aim of the study was to evaluate the potential of these data for monitoring vegetation at the species level in the Central European relict arcto-alpine tundra (in the Krkonoše Mountains, Czech Republic). We evaluated both types of data and their performance for various classifiers, and the benefits of adding multi-temporal aspects to the classification and robustness of remote sensing for monitoring grass species. This study addresses the requirements of nature conservation practices in the Krkonoše Mts. National Park to find a suitable method for monitoring changes in dominant and expanding grass species in response to global warming. The object-based Support Vector Machine, pixel-based Random Forest and Maximum Likelihood classifiers were evaluated. We confirmed that the UAV multispectral and hyperspectral data with GSD of 3 cm can monitor dominant grass species (Nardus stricta, Calamagrostis villosa, Molinia caerulea, Deschampsia cespitosa) in tundra with excellent accuracy (95.9% and 94.0% overall accuracy for multi-temporal and mono-temporal composites, respectively). The best F1-scores for these species ranged from 94.7 to 99.4%. However, the accuracies were substantially lower for small and sparse growing species (Avenella flexuosa and Carex bigelowii). Unexpectedly, the UAV multispectral and hyperspectral data yielded comparable results. The multi-temporal approach improved the accuracy of all types of data. Overall, we confirmed the robustness of the remote sensing approach for grass monitoring at the species level given the high spatial match between various classification outputs. Our study established a workflow for reliable monitoring of tundra grass vegetation according to the requirements of nature conservation and proposed innovative measures for the spatial accuracy assessment of classification outputs.

Seasonality, C:N ratio and plant species influence on denitrification and plant nitrogen uptake in treatment wetlands

Synthetic wastewater with an average total dissolved nitrogen (TDN) concentration of 72 mg l−1 (18 NH4-N and 54 NO3-N) and three organic carbon‑nitrogen (C:N) ratios (0, 1.2, 2.4) was batch-loaded to 72 microcosms planted in monocultures of five plant species or left unplanted. Water quality was measured at 0, 1, 3, 6, 9, and 15 days during 15-day incubations at eight temperature settings ranging from 4 to 24 °C. This allowed for comparisons of TDN removal as influenced by plant species, temperature, and C:N ratio. Strong interactions between independent variables influence interpretation. At a C:N ratio of zero, all plant species significantly increased TDN removal compared to the unplanted microcosms. However, unplanted microcosms showed nearly complete TDN removal at the highest C:N ratio and warm temperatures; removal decreased with decreasing temperature and C:N ratio. TDN removal in Deschampsia cespitosa and Typha latifolia was better but responded similarly to unplanted with respect to temperature and C:N ratio. Conversely, microcosms of Phragmites australis and Schoneoplectus acutus had complete and rapid removal of all applied TDN (177 g N m−2 yr−1) under all C:N ratios and temperatures. Complete TDN removal was observed in Carex utriculata for all C:N ratios and temperatures except for the coldest temperature (4 °C). However, increasing the C:N ratio at this temperature increased TDN removal. Higher C:N ratios increase TDN removal, likely by increased denitrification, but simultaneously reduce plant biomass and plant uptake of nitrogen. Overall, removal of nitrate was enhanced with organic carbon addition and warm temperature, but specific plant species promoted complete removal even without organic carbon and in winter.

Effect of Drought on the Development of Deschampsia caespitosa (L.) and Selected Soil Parameters during a Three-Year Lysimetric Experiment.

This work presents results from a field experiment which was focused on the impact of the drought period on microbial activities in rhizosphere and non-rhizosphere soil. To demonstrate the effect of drought, the pot experiment lasted from 2012 to 2015. Fifteen lysimeters (plastic containers) were prepared in our area of interest. These lysimeters were filled with the subsoil and topsoil from this area and divided into two groups. The first group consisted of two variants: V1 (control) and V2 (84 kg N/ha), which were not stressed by drought. The second group consisted of three variants, V3 (control), V4 (84 kg N/ha), and V5 (84 kg N/ha + 1.25 L lignohumate/ha), which were stressed by drought every year of the experiment for 30 days. Changes in the soil moisture content caused by drought significantly affect the growth of Deschampsia caespitosa L., the microbial activity, and the soil's capacity to retain nutrients. The measured basal respiration and dehydrogenase activity values confirm the significant effect of drought on microbial activity. These values were demonstrably higher in the period before drought simulation by more than 60%. On the other hand, significant differences between microbial activities in the rhizosphere and non-rhizosphere soil were not found. We did not find a clear effect of drought on the formation of soil water repellency.

Leaf Functional Traits in Relation to Species Composition in an Arctic–Alpine Tundra Grassland

The relict arctic-alpine tundra provides a natural laboratory to study the potential impacts of climate change and anthropogenic disturbance on tundra vegetation. The Nardus stricta-dominated relict tundra grasslands in the Krkonoše Mountains have experienced shifting species dynamics over the past few decades. Changes in species cover of the four competing grasses-Nardus stricta, Calamagrostis villosa, Molinia caerulea, and Deschampsia cespitosa-were successfully detected using orthophotos. Leaf functional traits (anatomy/morphology, element accumulation, leaf pigments, and phenolic compound profiles), were examined in combination with in situ chlorophyll fluorescence in order to shed light on their respective spatial expansions and retreats. Our results suggest a diverse phenolic profile in combination with early leaf expansion and pigment accumulation has aided the expansion of C. villosa, while microhabitats may drive the expansion and decline of D. cespitosa in different areas of the grassland. N. stricta-the dominant species-is retreating, while M. caerulea did not demonstrate significant changes in territory between 2012 and 2018. We propose that the seasonal dynamics of pigment accumulation and canopy formation are important factors when assessing potential "spreader" species and recommend that phenology be taken into account when monitoring grass species using remote sensing.