Search Results (129)

The Ichubamba Yasepan wetlands, in the Andean páramos of Ecuador, suffer heavy metal contamination due to anthropogenic activities and volcanic ash from Sangay, impacting biodiversity and ecosystem services. This quasi-experimental study evaluated the bioaccumulation and tolerance of metals in high Andean species through stratified random sampling and linear transects in two altitudinal ranges. Concentrations of Cr, Pb, Hg, As, and Fe in water and the tissues of eight dominant plant species were analyzed using atomic absorption spectrophotometry, calculating bioaccumulation indices (BAIs) and applying principal component analysis (PCA), clustering, and linear discriminant analysis (LDA). Twenty-five species from 14 families were identified, predominantly Poaceae and Cyperaceae, with Calamagrostis intermedia as the most relevant (IVI = 12.74). The water exceeded regulatory limits for As, Cr, Fe, and Pb, indicating severe contamination. Carex bonplandii showed a high BAI for Cr (47.8), Taraxacum officinale and Plantago australis for Pb, and Lachemilla orbiculata for Hg, while Fe was widely accumulated. The LDA highlighted differences based on As and Pb, suggesting physiological adaptations. Pollution threatens biodiversity and human health, but C. bonplandii and L. orbiculata have phytoremediation potential. Full article

To clarify the ecological mechanisms underlying the succession of artificial grasslands to native alpine meadows and systematically reveal the patterns of ecological restoration in artificial grasslands in the Qinghai–Tibet Plateau, this study provides a theoretical basis for alpine meadow ecological restoration. In this study, artificial grassland and degraded grassland (CK) with different restoration years (20 years, 16 years, 14 years, and 2 years) in the Qinghai–Tibet Plateau were taken as research objects. We focused on the tillering characteristics, patch number, community structure evolution, and soil properties of the dominant species, C. alatauensis, and systematically explored the ecological restoration law by comparing and analyzing ecological indicators in different restoration years. The results showed the following: (1) With the extension of restoration years, the asexual reproduction ability of C. alatauensis was enhanced, the patches became large, and aboveground/underground biomass significantly accumulated. (2) Community structure optimization meant that the coverage and biomass of Cyperaceae plants increased with restoration age, while those of Poaceae plants decreased. The diversity of four species in 20A of restored grasslands showed significant increases (10.71–19.18%) compared to 2A of restored grasslands. (3) Soil improvement effect: The contents of soil organic carbon (SOC), total phosphorus (TP), nitrate nitrogen (NN), and available phosphorus (AP) increased significantly with the restoration years (in 20A, the SOC content in the 0–10 cm soil layer increased by 57.5% compared with CK), and the soil pH gradually approached neutrality. (4) In artificial grasslands with different restoration ages (20A, 16A, and 14A), significant or highly significant correlations existed between C. alatauensis tiller characteristics and community and soil properties. In conclusion, C. alatauensis in artificial grasslands drives population enhancement, community succession, and soil improvement through patch expansion. Full article

Phytoremediation is based on the use of plants to decontaminate water and soil. In this work, the capacity of high Andean vegetation in the absorption and translocation of heavy metals was analyzed. Species were identified to analyze the presence of metals in roots, stems, and leaves by spectrometry. The translocation factor was determined and analyzed by means of pattern clusters. Based on the floristic inventory, the dominance of the Poaceae and Asteraceae families was determined, and 12 plant species with a high importance value were selected. According to the ICP-AES, mercury (951.07 mg/kg) was determined in the roots of Lachemilla orbiculata, and chromium (21.88 mg/kg) in Carex bonplandii. Arsenic (2.79 mg/kg) was detected as being significantly higher than the values recorded in lowland plants. Cadmium mobility was high in all species, reaching higher values in Baccharis salicifolia (86.28%) and Calamagrostis intermedia (37.16%). Rumex acetocella accumulated lead in leaves (9.27%), while Taraxacum officinale (1.20%) and Calamagrostis intermedia (1.20%) accumulated silicon. Stabilization of chromium, mercury, and sodium was determined in the roots without translocation to higher organs. Finally, cluster analysis showed physiological interactions between metals as a toxicity mitigation mechanism affecting mobility. These findings suggest that they are hyperaccumulator species. Full article

Nitrogen deposition is a critical driver of plant-soil interactions in forest ecosystems. However, the species-specific coordination of nitrogen uptake and carbon assimilation—traced using ¹⁵N- and ¹³C-labeled compounds—under varying nitrogen forms, depths, and time points remains poorly understood. We conducted a dual-isotope (¹⁵NH₄Cl, K¹⁵NO₃, and Na₂¹³CO₃) labeling experiment in a temperate secondary forest to investigate nutrient uptake and carbon assimilation in three understory species—Carex siderosticta, Maianthemum bifolium, and Oxalis acetosella—across three nitrogen treatments (control, low N, and high N), two soil depths (0–5 cm and 5–15 cm), and two post-labeling time points (24 h and 72 h). We quantified ¹⁵N uptake and ¹³C assimilation in above- and belowground plant tissues, as well as ¹⁵N and ¹³C retention in soils. C. siderosticta exhibited the highest total ¹⁵N uptake (2.2–6.9 μg N m⁻² aboveground; 1.4–4.1 μg N m⁻² belowground) and ¹³C assimilation (58.4–111.2 mg C m⁻² aboveground; 17.6–39.2 mg C m⁻² belowground) under high ammonium at 72 h. High nitrogen input significantly enhanced the coupling between plant biomass and nutrient assimilation (R² > 0.9), and increased ¹⁵N-TN and ¹³C-SOC retention in the surface soil layer (13,200–17,400 μg N kg⁻¹; 30,000–44,000 μg C kg⁻¹). Multifactorial analysis revealed significant interactions among nitrogen treatment, form, depth, and time. These findings demonstrate that ammonium-based enrichment promotes nutrient acquisition and carbon assimilation in responsive species and enhances surface soil C—N retention, highlighting the integrative effects of nitrogen form, species traits, and spatial–temporal dynamics on forest biogeochemistry. Full article

Endemic plant species, with their restricted distribution, are vulnerable to extinction due to human activities and environmental change. Monitoring their ecological characteristics and habitat relationships is crucial for conservation. This study examined plant communities to prioritize populations for conserving the Korean endemic species, Taihyun’s abelia (Zabelia tyaihyonii (Nakai) Hisauti & H.Hara), and to identify threats and strategies for its protection. Vegetation surveys were conducted, classifying communities and analyzing species composition differences. Habitat quality and zeta diversity, assessed using the InVEST model, identified three community types: Quercus dentata–Thuja orientalis (Com. 1), Fraxinus rhynchophylla–Buxus koreana (Com. 2), and Quercus dentata–Carex humilis var. nana (Com. 3). Community classification was supported by a multi-response permutation procedure (p < 0.001) and non-metric multidimensional scaling (R² = 0.643). Species richness and soil calcium influenced species composition, and habitat quality was moderate (0.5562 ± 0.0294). Com. 1 and Com. 3 showed minimal zeta diversity decline, indicating strong habitat connectivity. However, fluctuations at zeta orders 8–12 suggested localized disturbances. Species turnover instability was linked to urbanization and disturbance. This study, using a diverse set of analytical tools, was able to pinpoint key features of habitat quality and composition associated with Z. tyaihyonii and the anthropogenic factors that will lead to its decline. Our work provides a road map for the conservation of other rare and endemic Korean plant species with similar conservation issues. Full article

This study aimed to investigate the relationships between the mechanical properties of plant roots and the soil reinforcement characteristics of the dominant species in the dominant riparian plants under various flooding durations. The objective was to comprehensively evaluate the optimal flooding duration for each plant under various flooding durations. This research was conducted to provide a scientific basis for plant restoration efforts. The primary focus of the study was on common species found in the middle and lower reaches of the Yangtze River, including Carex, Cynodon, and Eleusine. These species were cultivated in a local field setting and subsequently subjected to flooding tests of varying durations. The diameter of the root system gradually increases with prolonged flooding duration, while other root morphologies exhibit a trend of initially increasing and then decreasing. The flooding environment significantly influences the relationship between root diameter and the mechanical properties of the roots. This condition adversely affects Carex, whereas it has a beneficial impact on Cynodon and Eleusine. During the early stages of flooding, the shear strength of the plant root–soil complex increases; Carex is optimally applied in the restoration and protection of areas subjected to three to four months of flooding, with its ornamental value being particularly pronounced. Cynodon performs best in areas with up to six months of flooding, Eleusine is especially effective in regions with less than two months of flooding. Full article

Pinus densiflora and Quercus mongolica are representative forest vegetation communities in Baekdudaegan, South Korea. Recently, signs of deterioration, such as natural succession, disease, and insect pests, have been detected. Therefore, this study aims to classify the vegetation types and elucidate the vegetation structure across the entire South Korean section of the Baekdudaegan, from Hyangrobong to Cheonwangbong, while also proposing strategies for vegetation conservation and management. A vegetation survey was conducted in 341 plots investigated from 2016 to 2020. Cluster analysis revealed nine community types, with a single indicator species, Rhododendron schlippenbachii, in Community 1 (C1); two, Fraxinus sieboldiana and Calamagrostis arundinacea, in C2; six, including Carex humilis var. nana, Polygonatum odoratum var. pluriflorum, and Quercus variabilis, in C3; three, Sasa borealis, Q. mongolica, and Erigeron annuus, in C4; two, Rhododendron mucronulatum and Vaccinium koreanum, in C5; twelve, including Lespedeza maximowiczii, Tripterygium regelii, and Fraxinus rhynchophylla, in C6; two, Toxicodendron trichocarpum and P. densiflora, in C7; twenty, including Acer pseudosieboldianum, Acer pictum var. mono, Staphylea bumalda, and Carex pediformis, in C8; and thirteen species, including Oplismenus undulatifolius, Castanea crenata, and Smilax china, in C9. Our findings highlight the need for management plans that consider each vegetation type’s community structural characteristics. Full article

Acid mine drainage (AMD) is a major environmental issue due to its high heavy metal concentrations and low pH, posing risks to ecosystems and human health. In Hualgayoc, Cajamarca, Peru, AMD contamination from mining activities necessitates effective remediation strategies. This study evaluated the removal efficiency of organic amendments, municipal waste compost (MWC), cattle manure compost (CMC), vermicompost (HMS), corn stalk biochar (CSB), sludge biochar (SLB), pine biochar (PBC), and native macrophytes Carex pichinchensis (CAX), Juncus ecuadoriensis (JSP), and Myriophyllum aquaticum (MYA) in removing As, Cd, Cu, Fe, and Zn. A physicochemical characterization of AMD, amendments, and plants was conducted, and sorption capacity was determined through triplicate analyses. The results showed that SLB achieved a 100% Zn removal, while CSB removed over 90% of Cu and Fe. Among the organic amendments, CMC demonstrated the highest As and Cd removal (~100%). Regarding macrophytes, CAX achieved a ~97% Fe removal, and MYA exhibited Cd affinity. CSB had the highest sorption capacity for Cu (0.139 mg/g), Fe (1.942 mg/g), and Zn (0.149 mg/g), highlighting its potential for metal remediation. Organic amendments enhanced metal adsorption and stabilization, outperforming macrophytes in heavy metal removal. Combining organic amendments with native plants is recommended to assess their synergistic potential for AMD remediation. Full article

Wetland vegetation is vital for ecological purification and climate mitigation. This study analyzes the spatiotemporal characteristics and influencing factors of water areas, fractional vegetation cover (FVC), and land use types in Poyang Lake wetland across wet and dry seasons (1990–2022) using remote sensing technology. The results showed that the water area remained overall stable during the wet seasons but decreased significantly in the dry seasons (19.27 km²/a). FVC exhibited an overall increasing trend, with vegetation expanding from lake margins to central areas. The land use areas of shallow water, bare ground, and Phalaris arundinacea–Polygonum hydropiper (P. arundinacea–P. hydropiper) communities showed interannual fluctuating decreases, while other land use types areas increased. From 1990 to 2020, land use changes were mainly characterized by the transformation of shallow water into deep water and bare ground, other vegetation into Carex cinerascens (C. cinerascens) community and bare ground, bare ground into deep water, as well as P. arundinacea–P. hydropiper community to C. cinerascens community. Rising temperatures enhanced FVC in both seasons, stimulated the expansion of C. cinerascens community area and total vegetation area, and reduced the dry season water area. Decreasing accumulated precipitation exacerbated water area loss and the decline of P. arundinacea–P. hydropiper communities. These findings provide critical insights for wetland ecological conservation and sustainable management. Full article

The European ground squirrel (Spermophilus citellus) is an endangered mammal that inhabits open habitats with low vegetation in central and southeastern Europe. Its southernmost range includes northern Greece, where populations are declining due to habitat degradation and fragmentation. Limited behavioural research on Greek populations underscores the need for studies to support conservation efforts. The present study examined the species’ diet and seasonal changes in food consumption in an anthropogenic area of Central Macedonia, Greece. Between 2022 and 2023, feeding behaviour was documented recording plant parts, taxa, and feeding durations, while plant availability was assessed through surface sampling. The results revealed that Cynodon, Carex–Cyperus, Salvia, Solanum, and Plantago were the dominant plant genera in the species’ diet, while rhizomes and leaves were the most frequently consumed plant parts. Seasonal dietary shifts were observed, with ground squirrels selecting specific plants and plant parts based on availability. Under resource-limited conditions, they adapted by consuming nutritious rhizomes or the less-common, but toxic, S. elaeagnifolium. These findings highlight the species’ dietary adaptability to Mediterranean and human-modified environments, providing valuable ecological insights and informing habitat conservation and improvement strategies. Full article

Alternaria includes endophytes, saprophytes, and pathogens affecting both plants and animals, with a global distribution across various hosts and substrates. It is categorized into 29 sections, each defined by a type species and six monophyletic lineages. The Alternaria section Nimbya comprises 10 species primarily associated with the families Juncaceae and Cyperaceae, functioning as either saprophytes or plant pathogens. In this study, 189 fungal strains were collected from multiple locations across six provinces in Iran. The isolates were initially classified based on morphological characteristics and ISSR-PCR molecular marker banding patterns. Multi-gene phylogenetic analyses of 38 selected strains, using ITS–rDNA, GAPDH, TEF1, RPB2, and Alt a 1 gene sequences, combined with morphological data, led to the identification of 13 species, including eight new species, namely Alternaria caricifolia, A. cyperi, A. juncigena, A. junci-inflexi, A. persica, A. schoenoplecti, A. salkadehensis, and A. urmiana. In addition, this work identified new host associations (matrix nova) for three previously known species: A. caricicola on Cyperus sp., A. cypericola on Eleocharis sp., and A. junci-acuti on Carex sp. The study provides detailed morphological descriptions and illustrations of all identified species, discusses their habitats, distribution, and phylogenetic relationships within section Nimbya, and presents a key for species identification within this section in Iran. Furthermore, these findings highlight the significance of studying fungal biodiversity in Iran and contribute to a better understanding of species distribution and host range within the Alternaria section Nimbya. Full article

From the point of view of farming utilization, investigations on the recognition of the mineral composition of sedges appears important, appropriate and useful. Sedges are often found in many meadow and pasture communities. It is therefore worth paying attention to the mineral content of their tissues and their possible impact on the organisms of farm animals such as pigs. The basic objective of this study was to determine the concentration of selected macro and microelements: phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), sodium (Na), iron (Fe), silicon (Si), copper (Cu), zinc (Zn), chrome (Cr) and nickel (Ni) in the biomass of seven sedge species, potentially used as fodder, commonly occurring in natural sites in Central Europe. The material was collected twice during one growing season in the Krześniczka (N 52°37′14′ E 14°46′06′)—lubuskie voivodeship. The first harvest was carried out at the beginning of May, during the shooting and earring phase. The collected plant material included stems and leaves. The second harvest—the end of June—was collected at a time when the seedlings were developing flowers and young fruits, and their vegetative organs were developing dynamically. In June, the collected material represented organs in all possible development phases. The collected material was dried at a temperature of 65 °C, ground, and analyzed. The obtained results showed a difference in the content of microelements between the May and June harvest dates in the dry matter of all analyzed sedge species, which differed statistically significantly only in relation to copper. The harvest date had a statistically significant impact on the change in the content of macroelements in the dry matter of all analyzed sedge species and was associated with a decrease in the content of phosphorus, magnesium and calcium, while in the case of silicon, the delay in mowing resulted in an increase in the content of this element. Full article

The alpine steppe has an important place in alpine ecosystems, and its distribution pattern is strongly influenced by climate change. In this study, we used “biomod2” and “FragStats 4.2” to calculate the migration trends and the habitat fragmentation of three S. purpurea alpine steppes on the western Tibetan Plateau. The results of this study show that the Stipa purpurea-Ceratoides compacta alpine steppe, the Stipa purpurea-Carex moorcroftii alpine steppe, and the Stipa purpurea-Carex montis-everestii alpine steppe are strongly influenced by climate, while other variables have less impact. Their main influence factors are annual precipitation (Bio12), precipitation of the warmest quarter (Bio18), and precipitation of the coldest quarter (Bio19), respectively. The effects of carbon emissions on the suitable habitats of all three S. purpurea alpine steppes are significant in future scenarios. Continued increases in carbon emissions will lead to a continuous reduction in their suitable habitat areas. These communities are bounded by 33° N. South of the boundary, steppe communities are influenced by mountain ranges and show a tendency to migrate to higher elevations in a southward direction. North of the boundary, steppe communities show a tendency to migrate to higher elevations in a northward direction. Climate change reduces community aggregation, leading to gradual habitat fragmentation. The findings of this study provide a scientific basis for the migration and conservation of three S. purpurea alpine steppes on the western Tibetan Plateau, thereby contributing to the improvement of ecosystem stability and species diversity. Full article

Water use efficiency (WUE) plays a pivotal role in connecting the carbon and water cycles and represents the amount of water used by plants or ecosystems to achieve carbon sequestration. The response of WUE to climate warming and its underlying mechanisms remain unclear. Here, we examined the effects of varying levels of warming on carbon fluxes, water fluxes, and WUE in an alpine peatland, with Blysmus sinocompressus and Carex secbrirostris as dominant species. Open-top chambers were utilized to simulate two levels of warming: low-level warming (TL) and high-level warming (TH). The carbon dioxide and water fluxes were monitored over a growing season (June to September). Gradient warming significantly decreased both gross primary productivity (GPP) and net ecosystem carbon exchange (NEE); GPP was 10.05% and 13.31% lower and NEE was 21.00% and 30.00% lower in the TL and TH treatments, respectively, than in the control. Warming had no significant effect on soil evaporation, and plant transpiration and evapotranspiration were 36.98% and 23.71% higher in the TL treatment than in the control, respectively; this led to decreases of 31.38% and 28.17% in canopy water use efficiency (WUEc) and ecosystem water use efficiency (WUEe), respectively. Plant transpiration was the main factor affecting both WUEe and WUEc in response to warming. The findings underscore the essential function of water fluxes in regulating WUE and enhance our understanding of carbon–water coupling mechanisms under climate change. Full article

Carex is a type of herbaceous plant with high application value, playing an important role in the urban periphery. Due to its unique morphology and ecological characteristics, Carex is widely used in various fields, such as landscaping, ecological restoration and soil and water conservation, which help to maintain the balance of the ecosystem. In order to explore the potential molecular mechanisms of shade tolerance in Carex, transcriptome and metabolome sequencing were performed on the leaves of the shade = tolerant species Carex adrienii E. G. Camus. under 80% shade and no shade conditions. Compared to control group (CK), the total chlorophyll, chlorophyll a, chlorophyll b and total carotenoid content in the C. adrienii leaves of the shading treatment were significantly upregulated. The antioxidant enzyme activity of the leaves, including superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT), were also remarkably upregulated in the shading treatment groups. In addition, the net photosynthesis rate (Pn), stomatal conductance (Gs) and transpiration rate (Tr) of the leaves were reduced, and the intercellular CO₂ concentration (Ci) of the leaves was increased under shade. The transcriptome identified 5056 differentially expressed genes (DEGs) and the metabolome identified 889 differential accumulated metabolites (DAMs) in three treated samples. The integrated transcriptomic and metabolomic analyses results showed that the DEGs and DAMs were enriched in photosynthesis, plant hormone signal transduction and flavonoid biosynthesis synthesis pathways. The ABA content of the C. adrienii leaves was significantly increased under shade. Therefore, the shading conditions led to changes in chlorophyll and abscisic acid (ABA), as well as the accumulation of flavonoids in C. adrienii, both of which were achieved by regulating genes involved in photosynthesis, plant hormone signal transduction and flavonoid biosynthesis molecular networks. Our results provide new knowledge for the molecular response and metabolic regulatory mechanisms of C. adrienii to shade stress, and valuable genetic resources for C. adrienii shade tolerance molecular breeding. Full article