Altitudinal Impact on Phytochemical Composition and Mycorrhizal Diversity of Taxus Contorta Griff in the Temperate Forest of Shimla District.

Taxus contorta (family Taxaceae) is a native plant of temperate region of western Himalaya. The current study investigated the effect of altitude on the phytochemical composition and mycorrhizal diversity, associated with distribution of T. contorta in Shimla district, Himachal Pradesh, India. Quantitative phytochemical analysis of the leaf extracts indicated that alkaloid levels decreased with altitude, with the highest value in Himri's methanol extracts (72.79 ± 1.08 mg/g) while phenol content increased with altitude, peaking in Nankhari's methanol extracts (118.83 ± 5.90 mg/g). Saponin content was higher in methanol extracts (78.13 ± 1.66 mg/g in Nankhari, 68.06 ± 1.92 mg/g in Pabbas, and 56.32 ± 1.93 mg/g in Himri). Flavonoid levels were notably higher in chloroform extracts, particularly in Nankhari (219.97 ± 2.99 mg/g), and positively correlated with altitude. Terpenoids were higher in chloroform extracts at Himri (11.34 ± 0.10 mg/g) and decreased with altitude. Taxol content showed minimal variation between solvents and altitudes (4.53-6.98 ppm), while rutin was only detected in methanol extracts (1.31-1.46 ppm). Mycorrhizal spore counts in T. contorta's rhizosphere varied with altitude: highest at Himri (77.83 ± 2.20 spores/50 g soil), decreasing to Pabbas (68.06 ± 1.96 spores/50 g soil) and lowest at Nankhari (66.00 ± 2.77 spores/50 g soil), with 17 AMF species identified overall, showing significant altitudinal influence on spore density. The rhizosphere of T. contorta was shown to be dominated by the Glomus species. The rhizospheric soil of the plant was found to be slightly acidic. Organic carbon and available potassium content decreased contrasting with increasing available nitrogen and phosphorus with altitude. Correlation data showed strong negative links between organic carbon (-0.83), moderate positive for nitrogen (0.46) and phosphorus (0.414), and moderate negative for potassium (-0.56) with the altitude. This study provides a comprehensive insight into changes in phytochemical constituents, mycorrhizal diversity and soil composition of T. contorta along a range of altitude.

Preliminary investigation on the causes of red tides in Qinhuangdao coastal areas in 2022.

To explore the causes of red tides in Qinhuangdao coastal water, we conducted surveys on both water quality and red tides during April to September of 2022 and analyzed the relationships between main environmental factors and red tide organisms through the factor analysis and canonical correspondence analysis. The results showed that there were eight red tides along the coast of Qinhuangdao in 2022, with a cumulative blooming area of 716.1 km2. The red tides could be divided into three kinds based on the major blooming organisms and occurrence time, Noctiluca scintillans bloom, diatom-euglena (Skeletonema costatum, Eutreptiella gymnastica, Pseudo-nitzschia spp.) bloom, and dinoflagellate (Scrippsiella trochoidea and Ceratium furca) bloom. Seasonal factor played roles mainly during July to September, while inorganic nutrients including nitrogen and phosphorus influenced the blooms mainly in April and July. The canonical correspondence analysis suggested that N. scintillans preferred low temperature, and often bloomed with high concentrations of ammonium nitrogen and dissolved inorganic phosphorus. S. costatum, E. gymnastica, and Pseudo-nitzschia spp. could tolerate broad ranges of various environmental factors, but favored high temperature and nitrogen-rich seawater. C. furca and S. trochoidea had higher survival rate and competitiveness in phosphate-poor waters. Combined the results from both analyses, we concluded that the causes for the three kinds of red tide processes in Qinhuangdao coastal areas in 2022 were different. Adequate diet algae and appropriate water temperature were important factors triggering and maintaining the N. scintillans bloom. Suitable temperature, salinity and eutrophication were the main reasons for the diatom-euglena bloom. The abundant nutrients and seawater disturbance promoted the germination of S. trochoidea cysts, while phosphorus limitation caused the blooming organism switched to C. furca and maintained the bloom hereafter.

Essential oil composition, morphological characterization, phenolic content and antioxidant activity of Iranian populations of Hymenocrater longiflorus Benth. (Lamiaceae).

The study focused on the morphological and chemical characteristics of 200 Hymenocrater longiflorus Benth. genotypes found in natural habitats of eight regions in west of Iran. The primary objective of the study was to assess the morphological and phytochemical variability within populations grown in their natural habitats, with the aim of identifying their potential for domestication and utilization in pre-breeding programs. The plant height (PH) ranged from 50.32 to 69.65 cm, with the highest observed in population P8. The internode distances ranged from 4.7 to 6.47 cm, with the maximum distance found in P4. Flower lengths varied from 1.95 to 2.45 cm, with the minimum and maximum values observed in P4 and P3, respectively. The highest leaf length (5.20 cm) and width (3.87 cm) were recorded in P2. The aerial parts of the plant were utilized to extraction and determine the essential oil (EO) content and composition, which ranged from 0.40 to 0.78% (v/w). The analysis of EO by gas chromatography (GC) and gas chromatography mass spectrometry (GC/MS) identified 26 compounds, constituting 99-99.5% of the EOs. The main compounds in the EO and their percentage range (v/w DW) were tau-cadinol (0.62-55.56), mono (2-ethylhexyl) phthalate (8.10-94.70), elemol (0.21-19.11), ß-spathulenol (0.08-14.39), 4-terpineol (0.23-10.19), and ß-eudesmol (0.21-9.94). The main chemical groups found in EOs included oxygenated sesquiterpenes (1.12-68.43), and phthalates (9.73-94.72). Cluster analysis revealed three distinct chemotypes: chemotype I (populations 1 and 2) with major components of mono (2-ethylhexyl) phthalate, tau-cadinol, and α-elemol; chemotype II (population 5) rich in mono (2-ethylhexyl) phthalate; and chemotype III (populations 3, 4, 6-8) containing tau-cadinol, ß-eudesmol, and 4-terpineol. The study also evaluated total phenolic, total flavonoid, and DPPH free radical scavenging activity in the fifty percent inhibitory concentration (IC50) in leaf and flower samples of the genotypes, along with estimating total anthocyanin content in the flower samples. The total phenolic content (TPC) in leaf and flower samples ranged from 7.89 to 107.18 mg GAE/g DW and 39.98 to 86.62 mg gallic acid equivalent (GAE)/g DW, respectively. Total flavonoid content (TFC) ranged from 81.04 to 143.46 mg QUE/g DW in leaf samples and from 94.82 to 133.26 mg quercetin equivalent (QUE)/g DW in flower samples. DPPHsc IC50 (µg/mL) ranged from 0.65 to 78.74 in leaf samples and from 4.38 to 7.71 in flower samples. Anthocyanin content ranged from 1.89 to 3.75 mg cyanidin-3-glucoside equivalent (C3GE)/g DW among populations. Canonical correspondence analysis and simple correlation demonstrated a strong association and correlations among the studied attributes. The negative correlations between leaf DPPH (DPPH L) IC50 and TFC (- 0.73), TPC (- 0.63), Elemol (- 0.90), and EO (- 0.85) indicate that these compounds have a significant impact on the antioxidant activity of the leaves. Furthermore, Fruit DPPH (DPPH F) IC50 showed a negative correlation with TPC (- 0.79) and TFC (- 0.78), but a positive correlation with flower anthocyanins (0.51), (Z)-ß-Farnesene (0.66), and 4-Terpineol (0.57). Circular cluster analysis categorized the genotypes of all individuals in the eight studied populations into three main categories based on all the studied traits, indicating significant variation in phytochemical and morphological traits among populations, surpassing the within-populations variation.

Temporal Variations in Plankton Communities and Environmental Factors in the Shipra, a Central Himalayan Tributary of the Kosi River in Uttarakhand, India.

The essential role of smaller streams and tributaries indigenous to the area is crucial in revitalizing and restoring the main river system. The present study unraveled the relationship between plankton communities and environmental variables in the Shipra River, a Central Himalayan tributary of the Kosi River in Uttarakhand, India. Plankton distribution, abundance, and presence were investigated at four locations: upstream (S1 and S2) and downstream (S3 and S4). Forty-eight genera of phytoplankton and zooplankton have been identified belonging to ten classes (Bacillariophyceae, Chlorophyceae, Zygnematophyceae, Cyanophyceae, Euglenopyceae, Protozoa, Rotifers, Copepoda, Cladocera, and Insecta) based on the findings. Winter was dominated by phytoplankton (Navicula spp., Nitzchia spp., Diatom spp.); summer and monsoon by zooplankton (Daphnia spp., Cyclops spp., Keratella spp., Brachionus spp.). Plankton communities of the tributary were assessed using diversity indices (Shannon-Weiner's index (H), Simpson's diversity index (1-D), and Evenness Index (E)). Seasonal variations in water temperature, specific conductivity, total dissolved solids, dissolved oxygen, nitrate, and ammonium ions were found to be statistically significant (p<0.05). Canonical Correspondence Analysis, K-dominance plots, cluster analysis, and NMDS analysis showed the dynamic nature of the plankton communities with seasonal physiochemical variations in the unexplored Himalayan tributary. The plankton communities exhibited significant temporal fluctuations with physicochemical factors.

Shrimp community structure and influence of environmental variables in the East China Sea and Yellow Sea in spring.

Based on data collected from research vessel cruises performed in May 2020 off the East China Sea (ECS) and the southern Yellow Sea (YS) (26°30'-35°00' N, 120°30'-127°00' E), we analyzed the shrimp community and its relationships with environmental variables by using index of relative importance, biodiversity indices, and multivariate techniques. A total of 29 species were recorded, belonging to 11 families and 19 genera. The dominant species were Metapenaeopsis longirostris, Leptochela gracilis, Solenocera melantho, Crangon hakodatei, Parapenaeus fissuroides, Plesionika izumiae, and Trachypenaeus curvirostris, which together accounted for 82.9% of the total biomass and 90.8% of the total abundance of shrimps. Results of Cluster and NMDS analyses showed that three groups were identified for the shrimp community in the ECS and YS in spring, including group A (inshore of northern ECS and YS group), group B (offshore of northern ECS group) and group C (southern ECS group). ANOSIM and SIMPER analysis showed significant differences between group A and B, gourp A and C, and group B and C, with the dissimilarity of 92.2%, 95.8% and 91.6%, respectively. The typical species were T. curvirostris, C. hakodatei, L. gracilis and Palaemon gravieri in group A, and S. melantho in group B, and M. longirostris, P. fissuroides, P. izumiae and Solenocera alticarinata in group C. Significant differences were also detected in biomass, diversity index, species richness index and evenness index among groups, with significantly greater values in group C than those in A and B. Environmental variables and the substrate also displayed significant differences among groups. Results of canonical correspondence analysis showed that bottom temperature, bottom salinity, depth, and the substrate were the main environmental variables affecting spatial structure of shrimp community. Water mass characteristics and substrate type had important influences on the distribution of shrimp community in the ECS and YS in spring.

Microbial genome (Illumina MiSeq) sequencing of drinking water treatment residuals to evaluate compatibility with environmental applications.

The clarification of drinking water leads to the production of large quantities of water treatment residuals (WTRs). DNA was extracted from six WTR samples collected from water treatment plants within the UK to compare their bacterial communities and examine whether factors such as coagulant usage (aluminium versus iron salt), the type of water source (reservoir or river), or leachable chemical composition influence these communities. Bacterial 16S variable region 4 (V4) was amplified and sequenced using Illumina MiSeq sequencing. The most abundant phyla in WTR samples were Proteobacteria, Actinobacteria, Bacteroidetes, Acidobacteria, and Firmicutes, collectively representing 92.77-97.8% of the total bacterial sequences. Statistical analysis of microbial profiles indicated that water source played a significant role in microbial community structure, diversity, and richness, however coagulant type did not. PERMANOVA analysis showed that no single chemical variable (pH, organic matter, or extractable element concentration) influenced microbial composition significantly; however, canonical correspondence analysis of WTR microbiomes yielded a model using all these variables that could be used to explain variations in microbial community structures of WTRs (p < 0.05). No common, potentially toxic cyanobacteria, or related pathogens of concern were found. Analysis with PICRUSt showed that WTRs all had similar predicted microbial functional profiles. Overall, the results indicate that WTRs analysed in this study are unlikely to pose any threat to soil microbial community structure when applied to land as a soil conditioner or enhancer and may help to enhance the soil microbial community.

Phytoplankton Community Structure Dynamics in Relation to Water Environmental Factors in Zhalong Wetland.

Phytoplankton, as the primary producer of the wetland water ecosystem's food chain, are very sensitive to environmental changes. In order to explore the significance of phytoplankton in protecting ecosystem integrity, the wetland ecosystem in Zhalong wetland, one of the most important international wetlands, was selected as the research area. For the study, 81 sampling sites were set up in the whole wetland, and phytoplankton samples and water quality environmental factors were measured in spring, summer, and autumn of 2019. The phytoplankton community structure and water environmental factors were evaluated by canonical correspondence analysis (CCA). The main research findings are as follows: a total of 292 species and variants of phytoplankton belonging to 8 phyla and 110 genera were identified within Zhalong wetland in spring, summer, and autumn 2019. The total phytoplankton abundance and biomass in summer were higher than in spring and autumn, and Cyclotella meneghiniana was the most dominant species in three seasons and three areas. The results of random forest are generally consistent with the results of CCA in spring, when the main environmental factors affecting phytoplankton were NTU and WT; the result in summer and autumn agreed with those of CCA, which awaits further study. In addition, the phytoplankton is mainly affected by WT, depth, and DO in the lake area, TP, DO, and NTU in the river area, and WT in the wetland area.

Variations in mitragynine content in the naturally growing Kratom (Mitragyna speciosa) population of Thailand.

We analyzed the content of mitragynine (MG) found in kratom leaves (Mitragyna speciosa) and the influence of different environmental conditions (air and soil variables) on the yield in various regions of Thailand. The content of MG in kratom leaves ranged from 7.5 - 26.6 mg g-1 of dry leaf weight. Canonical correspondence analysis showed that the most significant environmental variables affecting the MG content among the various regions were light intensity, relative humidity, soil volumetric water content (VW), soil pH, and calcium. This study is a first step towards providing information about environmental conditions suitable to maximize the quality and quantity of bioactive alkaloids in kratom. Future studies should focus on leaf collection and the post-harvest processes in order to assure the desired alkaloidal content in finished products, when produced under suitable environmental conditions identified in this study.

[Characteristics of Phytoplankton Community Structure and Their Relationships with Environmental Factors in Autumn in Qinhe River Basin of Jincheng Region].

In October-November 2020, the phytoplankton and the aquatic environment from 62 sites in the mainstream of the Qinhe River and the largest tributary of the Qinhe River (Danhe River) in the Jincheng region were investigated to clarify the spatial pattern of phytoplankton communities and their driving factors. A total of 7 phyla and 47 species of phytoplankton were identified in the Qinhe River basin and were composed of Cryptophyta, Chlorophyta, Pyrrophyta, Chrysophyta, Bacillariophyta, Cyanophyta, and Crytophyta. Six dominant species in the Qinhe River included:Chlorella vulgaris, Cryptomonas erosa, Chroomonas acuta, Cyclotella stelligera, Chlorococcum, and Euglena viridis. Six dominant species in the Danhe River included:C. erosa, Frustulia vulgaris, E. viridis, C. vulgaris, Trachelomonas oblonga Lemm, and C. stelligera. The Shannon-Wiener diversity index (H') varied from 0.35 to 3.15, with a mean value 1.40. The Pielou evenness index (J) varied from 0.24 to 1.00, with a mean value of 0.68. H' values in the Qinhe River were higher than those in the Danhe River. J values were relatively low in the middle reaches of the Qinhe River and middle-low reaches of the Danhe River. The results in the Qinhe River through a canonical correspondence analysis (CCA) showed that the percent of forest land at a 300 m buffer was the driving factor of Chlorococcum in Chlorophyta, and nitrate, total phosphorus, and the percent of forest land at the 300 m buffer were the driving factors of E. viridis. Cyclotella stelligera was mainly influenced by the percent of urban land and water temperature, whereas C. vulgaris, C. erosa, and C. acuta were mainly influenced by the percent of farmland and residential land at the 300 m buffer. The results in the Danhe River via CCA showed that C. erosa and C. stelligera were mainly influenced by pH and sulfate, E. viridis was mainly influenced by the percent of urban land and grass land, T. oblonga Lemm was mainly influenced by chloride and the percent of forest land, F. vulgaris was mainly influenced by water temperature and the percent of farmland, and C. vulgaris was mainly influenced by ammonia and the percent of farmland.

Plants predict the mineral mines - A methodological approach to use indicator plant species for the discovery of mining sites.

INTRODUCTION: There has been limited research conducted on the identifications/methodological approaches of using plant species as indicators of the presence of economically, important mineral resources. OBJECTIVES: This study set out to answer the following questions (1) Do specific plant species and species assemblages indicate the presence of mineral deposits? and (2) if yes, then what sort of ecological, experimental, and statistical procedures could be employed to identify such indicators? METHODS: Keeping in mind these questions, the vegetation of subtropical mineral mines sites in northern Pakistan were evaluated using Indicator Species Analysis (ISA), Canonical Correspondence Analysis (CCA) and Structural Equation Modeling (SEM). RESULTS: A total of 105 plant species belonging to 95 genera and 43 families were recorded from the three mining regions. CA and TWCA classified all the stations and plants into three major mining zones, corresponding to the presence of marble, coal, and chromite, based on Jaccard distance and Ward's linkage methods. This comprehended the following indicator species: Ficuscarica, Isodonrugosus and Ajugaparviflora (marble indicators); Oleaferruginea, Gymnosporiaroyleana and Diclipterabupleuroides (coal indicators); and Acacianilotica, Rhazyastricta and Aristidaadscensionis (chromite indicators) based on calculated Indicator Values (IV). These indicators were reconfirmed by CCA and SEM analysis. CONCLUSION: It was concluded that ISA is one of the best techniques for the identification/selection of plant indicator species, followed by reconfirmation via CCA and SEM analysis. In addition to establishing a robust approach to identifying plant indicator species, our results could have application in mineral prospecting and detection.

Plant diversity and community analysis of Sele-Nono forest, Southwest Ethiopia: implication for conservation planning.

BACKGROUND: Studying the floristic diversity of a certain forest is a basic aspect of the design and management of forest vegetation; and consequently this study focused on the plant diversity and community analysis of the Sele-Nono forest. For the current study, plants were sampled from 90 plots using a stratified random sampling technique along the established strata of the study forest. In all the plots, both floristic and environmental data that were relevant to the study were collected following the state of the art. Based on the collected data, the community types, ordination, floristic diversity, and threats to the forest were analyzed using R-package and SPSS software. RESULTS: Cluster analysis produced seven distinct community types which significantly differed among themselves (Cophentic correlation coefficient = 0.785, P < 0.001) of which community types 2 and 6 were relatively poor; whereas communities 1 and 4 were rich in terms of their species richness and diversity. In addition, Canonical Correspondence Analysis (CCA) suggests that a number of environmental factors such as altitude and slope (topographic factor), OM and N (edaphic factors) and disturbance were the main drivers for the current distribution of plant species and disparity in plant community composition in Sele-Nono forest. Moreover, the study revealed high beta diversity ([Formula: see text] >12) of plant species at the landscape level (i.e., throughout the study forest). Deforestation for agricultural land expansion and degradation through selective logging are the main threats to the Sele-Nono forest. CONCLUSIONS: The present study revealed that the Sele-Nono forest is a large and heterogenous forest at the landscape level (150, 325.27 ha; [Formula: see text] >12). Moreover, it is one of the richest and diverse forest ecosystems in terms of plant biodiversity, and it could qualify to be labeled as a keystone ecosystem. However, currently it is exposed to a variety of threats. We recommend the forest to be developed into a biosphere reserve. We also recommend the prioritization of areas belonging to community types 2 and 6 of the forest for any possible conservation actions so as to maximize species richness and diversity of the native plants of the area.

Effects of environmental and spatial gradients on Quercus-dominated Mountain forest communities in the Hindu-Kush ranges of Pakistan.

Quercus-dominated forests are among the most important broad-leaved evergreen forests of the Hindu Kush ranges and are currently prone to drastic anthropogenic and climatic changes. The aim of this study was to provide basic data for the development of a regional oak forest ecosystem framework for ecological restoration and management plan development to maintain local peoples' livelihoods. Hence, we analyzed distribution patterns and environmental factors that affect regional oak forests' species composition and diversity. Ward's Agglomerative clustering divided oak-dominated forest communities into three groups: i.e., Group I, dominated by Quercus baloot had an importance value index (IVI) of 89.87 ± 4.31, Group II, dominated by Quercus dilatata had an IVI of 32.16 ± 15.01, and Group III, dominated by Quercus oblongata had an IVI of 83.14 ± 4.67, respectively. The environmental factors which vary significantly within these communities were latitude, elevation, clay content and bulk density of the soil. Wilting point, saturation point, and electrical conductivity were also considered as ecosystem structural variables. Canonical correspondence analysis (CCA) indicated that community structure was affected by various environmental factors including precipitation, slope angle, elevation, clay content, and relative humidity.

Temporal and Spatial Patterns of Sediment Microbial Communities and Driving Environment Variables in a Shallow Temperate Mountain River.

Microbial communities in sediment play an important role in the circulation of nutrients in aquatic ecosystems. In this study, the main environmental factors and sediment microbial communities were investigated bimonthly from August 2018 to June 2020 at River Taizicheng, a shallow temperate mountain river at the core area of the 2022 Winter Olympics. Microbial community structure was analyzed using 16S rRNA genes (bacteria 16S V3 + V4 and archaea 16S V4 + V5) and high-throughput sequencing technologies. Structure equation model (SEM) and canonical correspondence analysis (CCA) were used to explore the driving environmental factors of the microbial community. Our results showed that the diversity indices of the microbial community were positively influenced by sediment nutrients but negatively affected by water nutrients. Bacteroidetes and Proteobacteria were the most dominant phyla. The best-fitted SEM model indicated that environmental variables not only affected community abundance directly, but also indirectly through influencing their diversity. Flavobacterium, Arenimonas and Terrimonas were the dominant genera as a result of enriched nutrients. The microbial community had high spatial-temporal autocorrelation. CCA showed that DO, WT and various forms of phosphorus were the main variables affecting the temporal and spatial patterns of the microbial community in the river. The results will be helpful in understanding the driving factors of microbial communities in temperate monsoon areas.

Summer-fall macrozooplankton assemblages in a large Arctic estuarine zone (south-eastern Barents Sea): Environmental drivers of spatial distribution.

Macrozooplankton assemblages were studied during the summer and fall of 2012 in the Pechora Sea, a large coastal region of the south-eastern Barents Sea strongly affected by discharges of freshwater. Sampling was performed at 23 stations with 550-µm mesh IKS-80 nets. We focused on macrozooplankton and large (>1.5 mm) non-copepod zooplankton (larvae of benthic animals and medusae). A combination of multivariate cluster analysis, diversity indices and canonical correspondence analysis was used to relate the spatio-temporal patterns of the zooplankton assemblages to environmental factors. Summer macrozooplankton density varied from 3 to 928 ind. m-3, averaging 131 ± 49 ind. m-3, with medusae being the most numerous (mean ± SE: 67.9 ± 7.8% of the total abundance). The total macrozooplankton biomass ranged from 0.3 to 516 mg dry mass (DM) m-3 with a mean value of 28 ± 25 mgDM m-3. There was a clear decline in the total macrozooplankton abundance (1.1-6.0, 4.4 ± 1.6 ind. m-3) and biomass (0.4-2.7, 1.2 ± 0.7 mgDM m-3) in fall when only two taxa (Parasagitta elegans and Mertensia ovum) were identified. Cluster analysis revealed three groups of stations in summer. The clusters were similar in terms of the abundance in common taxa but differed by the total density, biomass and diversity. We found that the offshore zone was dominated by the euphausiids Thysanoessa spp. and the chaetognaths Parasagitta elegans while the coastal area was characterized by high density of hydromedusae and larvae of bottom animals (Hyas spp., Pagurus spp.). There was a significant decline in the total macrozooplankton abundance and biomass from summer to fall. Canonical correspondence analysis showed that during the summer and fall of 2012, 68% of macrozooplankton variability was explained by environmental factors with water temperature and longitude being the most important. The distribution of macrozooplankton taxa was also related to local circulation patterns and possibly to mesozooplankton as potential prey for carnivorous taxa. Our data may be useful for future monitoring in the coastal Arctic estuarine regions.

Temporal Variation Dominates in Local Carabid Beetle Communities in Korean Mountains.

Spatial and temporal variation in ecological environments may result in spatial and temporal variation in communities. Temporal studies of biodiversity are essential for forecasting future changes in community structure and ecosystem function. Therefore, determining the mechanisms that drive temporal change in communities remains an important and interesting challenge in ecology. We quantified spatial and temporal variations in carabid beetle communities and site-specific environmental factors for 5 years at nine study sites on three mountains in the Baekdudaegan Mountain Range, Korea. Carabid beetle communities exhibited significant temporal variation, which was larger than spatial variations between and within mountains. Environmental factors mostly varied between sites within mountains. Community variation was only weakly associated with environmental factors at wide scales, i.e., between sites on three mountains, but was strongly associated at narrow spatial scales, i.e., between sites within one mountain. Our results indicate that temporal variation in communities occurs in response to variations in the local climate, and that the patterns of temporal variation differ between mountains. Thus, temporal surveys of insect communities and climates at local scales are important for predicting temporal changes in the communities.

Accumulation and distribution of microplastics in coastal sediments from the inner Oslofjord, Norway.

Microplastic presence in benthic marine systems is a widely discussed topic. The influence of the natural matrix on microplastic distribution within the sedimentary matrix is often overlooked. Marine sediments from the western inner Oslofjord, Norway, were investigated for temporal trends, with a particular focus on the relationship between sediment grain-sizes and microplastic distribution. Density separation, optical microscopy and chemical validation were used to categorize microplastics. Microplastic concentrations ranged from 0.02 to 1.71 MPs g -1 dry weight (dw). Fibres were the most common (76%), followed by fragments and films (18%, 6%). Common polymers were polyesters (50%), polypropylene (18%), polymethylmethacrylate (9%), rayon and viscose (5%) and elastane (4%). Microplastics appear to accumulate preferentially according to their morphology and polymer type in certain sediment grain-sizes. Microplastics inputs to the Oslofjord appear to derive from a wastewater treatment plant in the vicinity. Although, the redistribution of microplastics within the fjord needs further investigation.

Enhanced nitrogen and phosphorus removal by natural pyrite-based constructed wetland with intermittent aeration.

Four subsurface flow constructed wetlands (SFCWs) filled with different substrates including ceramsite, ceramsite+pyrite, ceramsite+ferrous sulfide, and ceramsite+pyrite+ferrous sulfide (labeled as SFCW-S1, SFCW-S2, SFCW-S3, and SFCW-S4) were constructed, and the removal of nitrogen and phosphorus by these SFCWs coupled with intermittent aeration in the front section was discussed. The key findings from different substrate analyses, including nitrification and denitrification rate, enzyme activity, microbial community structure, and the X-ray diffraction, revealed the nitrogen and phosphorus removal mechanism. The results showed that the nitrogen and phosphorus removal efficiency for SFCW-S1 always remained the lowest, and the phosphorus removal efficiency for SFCW-S4 was recorded as the highest one. However, after controlling the dissolved oxygen by intermittent aeration in the front section of SFCWs, the nitrogen and phosphorus removal efficiencies of SFCWs-S2 and S4 became higher than those of SFCW-S1, and SFCW-S3. It was noticed that the pollutants were removed mainly in the front section of the SFCWs. Both precipitation and adsorption on the substrate were the main mechanisms for phosphorus removal. A minute difference of nitrification rate and ammonia monooxygenase activity was observed in the SFCWs' aeration zone. The denitrification rates, nitrate reductase, nitrite reductase, and electron transport system activity for SFCW-S2 and SFCW-S4 were higher than those detected for SFCW-S1 and SFCW-S3 in the non-aerated zone. Proteobacteria was the largest phyla found in the SFCWs. Moreover, Thiobacillus occupied a large proportion found in SFCW-S2, and SFCW-S4, and it played a crucial role in pyrite-driven autotrophic denitrification.

Spatiotemporal variations in the composition of algal mats in wastewater treatment ponds of tannery industry.

Wastewater Treatment Pond (WTP) is an effective remediation technology for economically developing nations. Although it's excessive organic and nutrient loads with higher water logging time triggers mixed and unprofitable microalgal mats. This may serve as a seeding source for Cyanobacterial bloom in receiving waterbodies. Since, to maintain the growth of desirable algal species in WTPs, understanding towards environmental regulation and algal mat composition is important, especially for tropical countries, like India. In this study, biological treatment pond (BTP) and outlet pond (OP), of a tannery effluent treatment plant in eastern coast of India, were chosen for surveying the algal community composition concerning ecological parameters. Nearly, both the ponds were polluted, but the diversity was lower in BTP due to its elevated nutrient content (Ammonia 173 mg L-1) and higher persistent organic matters (COD 301.7 mg L-1) than OP. Using canonical correspondence analysis, seasonal variations showed higher species abundance during early summer compared to other seasons. A total of 37 taxa forming thick algal mats were recorded. The matrix of mats was mainly composed of Cyanobacterial members such as Phormidium, Leptolyngbya, Spirulina, and Pseudanabaena, followed by diatoms, especially Amphora and Nitzschia. Diatoms commonly occurred as embedded component in the entangled matrix of blue-green algal filaments. Hierarchical cluster analysis was employed to group all these taxa based on their seasonal appearance and abundance. This year-long intensive study revealing seasonal algal mat composition patterns in these WTPs will ultimately safeguard the livelihood and security of adjoining localities through proper site-specific pollution control.

The response of benthic foraminifera to heavy metals and grain sizes: A case study from Hainan Island, China.

Benthic foraminifera, heavy metals, and sediment grain sizes were studied in three bays of Hainan Island, and canonical correspondence analysis (CCA) and nonparametric regression were used to reveal the relationship between foraminifera and their environment. According to our survey, the three bays were moderately contaminated by Mo and As and uncontaminated to moderately contaminated by Pb, Zn, Cr, Sb, and Hg. The spatial pattern of heavy metals was comparable to sediment transport trends, indicating that their distribution was determined by sediment transport. Both living and dead foraminiferal assemblages were analyzed, and their compositions were similar, although the latter had a higher density and diversity. Based on the CCA method, species were divided into three groups, each of which responded differently to heavy metals and grain sizes. The response curves of individual species to heavy metals and grain sizes were obtained by using the Loess (locally weighted regression) method.

Response of benthic invertebrate assemblages to seasonal and habitat condition in the Wewe River, Ashanti region (Ghana).

Aquatic macro-invertebrates play a vital role in the food chain of river ecosystem at several trophic guilds and consumer levels, and are used as biomonitoring tools for aquatic ecosystem health. However, hydrologic conditions of these ecosystems have been severely altered because of the increase in urban development and agricultural expansion. This study examined benthic invertebrate response to processes that structure their community in the Wewe River, segmented into intact, medium, and severe condition zones. We sampled in 100 stations in a period of 4 months in the wet (June-September, 2019) and 3 months in the dry (January-March, 2020) seasons. Geometric series, rarefaction, and Hill numbers models were used to quantify invertebrate assemblages, while ordination technique, canonical correspondence analysis, was used to evaluate the influence of predictive factors on their assemblages. A total of 2,075 individuals belonging to 20 family taxa were registered. There was no significant difference in benthic assemblages between the dry and wet seasons. Predictive factors accounted for 47.04 and 50.84% variances, respectively. Taxa distribution patterns differed significantly only in the severely disturbed zone during the wet season. Neptidae, Libellulidae, and Chironomidae were the most abundant taxa, indicating their broad range habitat preference and their ability to adapt to seasonal changes. Asellidae and Perlidae were the least detected, suggesting their sensitivity to elevated levels of some water quality parameters. The findings highlight the threats to the benthic community and overall functional state of the Wewe River, with the need to consider the proposed conservation interventions indicated in this study.