Highest Diversity Index Research Articles

Characterization of Thirty Germplasms of Millet Pepper (Capsicum frutescens L.) in Terms of Fruit Morphology, Capsaicinoids, and Nutritional Components

Background: Millet peppers have rich and diverse germplasm resources. It is of great significance to characterize their phenotypes and physicochemical indicators. Methods: 30 millet germplasms were selected to measure the fruit length and width, flesh thickness, number of ventricles, fruit stalk length, and single fruit weight, and the texture characteristics of fruit such as hardness, cohesiveness, springiness, gumminess, and chewiness were determined by a texture analyzer. At the same time, high-performance liquid chromatography (HPLC) and gas chromatography (GC) were used to determine the fruit of capsaicin, dihydrocapsaicin, nordihydrocapsaicin, fatty acids, vitamin E (VE), total phenol, total sugar, and total dietary fiber. Results: M11 showed outstanding parameters in phenotype and texture. The coefficient of variation (CV) for VE was as high as 94.943% and the highest diversity index (H’) was total soluble solid, at 1.988%. M5 and M18 contained rich and diverse fatty acids. At the same time, the content of capsaicinoids in M18 also ranks among the top, second only to M27 (with a total capsaicin content of 5623.96 μg/g). PCA analysis using phenotypic data and physicochemical data showed that the classification results were different. Further hierarchical group analysis was carried out using all the index data. The results showed that 30 millet pepper germplasms were divided into three new categories: M5, M9, M18, and M24 formed one group (C1), M10, M14, M16, M19, M20, M22, M25, M26, M28, M29, and M30 formed another cluster (C2), and the remaining germplasms formed a third cluster (C3). Among them, the abundance of fatty acids in the C1 germplasm was higher than that in the other two groups. Conclusions: Our study showed that different germplasms had significant differences in morphological traits and nutritional metabolic components and were rich in genetic diversity. This study provides a theoretical basis for the improvement of millet varieties and the development of functional food.

GIS-based analysis of anti-Asian hate speech and its socioeconomic and ideological drivers in the United States during the early COVID-19 pandemic

Anti-Asian racism and xenophobia surged on social media during the COVID-19 pandemic, fueling discrimination and violence against Asians and Asian Americans in the United States. This study aims to understand the spatial patterns of Anti-Asian hate speech (AAHS) and identify the socioeconomic and ideological factors that may influence its emergence. Using Geographic Information System (GIS) tools, including hotspot analysis, Ordinary Least Squares (OLS), and Geographically Weighted Regression (GWR), we analyzed several socioeconomic and ideological factors to understand their impact on the spatial variability of AAHS risk levels. Our models show AAHS hotspots tend to cluster in suburban areas near the metropolitan and micropolitan regions. Our OLS model identifies three significant socioeconomic factors: the poverty level is negatively correlated with the AAHS risk level, but both high education level and diversity index demonstrate positive correlations with the AAHS risk level. The GWR model further explored local spatial patterns of how these factors influence AAHS levels. We suggest that anti-Asian sentiments may be driven by dominant groups fearing the loss of their identity and socioeconomic security. Additionally, in diverse areas, pandemic-related crises can exacerbate existing intergroup tensions, with structural inequalities further deepening divisions. Policymakers can leverage these findings to develop strategies aimed at mitigating the factors contributing to hate speech and effectively combating it. Future studies can expand on our findings to develop more robust theoretical frameworks for understanding these patterns.

Diversity of Pteridophytes in Different Vegetation Types of Mount Musuan, Bukidnon, Philippines

Two 20 m × 20 m plots were established per vegetation type—Natural Forest, Mixed/Biro, Thailand Shower, and Teak which recorded 38 pteridophyte species, from 28 genera, and 18 families. Highest diversity index was recorded in Mixed/Biro vegetation (H’=1.18), followed by Teak vegetation (H’=1.006), Thailand Shower (H’=0.886), and Natural Forest (H’=0.85). Pteridaceae had the highest number of species (6), Thelypteridaceae (4), Nephrolepidaceae (3) and Lygodiaceae (3). Sphaeropteris glauca is an endangered species and a new record for Mount Musuan, and Angiopteris evecta as other threatened species. The presence of these species highlights the importance of botanical exploration in Mount Musuan as well as the need for conservation management to protect its remaining biodiversity.

Biodiversity and Soil Characterization of Ancestral Domain of the Tagbanua Tribe in Aborlan, Palawan, Philippines

This study was conducted to determine strategies to enhance the sustainable forest management practices of the Tagbanua tribe. Specifically to describe the biodiversity and soil characteristics of the ancestral domain. The modified belt-transect method for biodiversity assessment developed by B+WISER (2014), further modified by the Department of Environment and Natural Resources (DENR) in the assessment, was used in this study. Results of soil chemical analysis showed significant variations among various land uses. The ancestral domain had at least 73 plant species belonging to 34 families and 59 genera. Four (4) taxa whose SN/families were still undetermined and another three (3) genera under families Annonaceae, Meliaceae, and Sapindaceae were unidentified. It had 12 plant species that are threatened with one critically endangered based on the list of threatened Philippine plants of the DENR. On the other hand, a total of 372 birds representing 61 species from 29 families were recorded. The high Shannon-Weiner Diversity Index (H’=3.69) and Shannon’s Evenness (HE=0.90) values indicate high avifaunal diversity and equitable distribution among the detected species. Most of the conservation priority species recorded in the area are Palawan endemic species. The survival of these birds is threatened by extinction due to habitat loss. This observation emphasized the importance of the ancestral domain as a refuge for these endemic species and conservation priority areas.

Bird Commmunity in Bagek Kembar Mangrove Essential Ecosystem Area (EEA), Sekotong, West Lombok

Birds are wildlife found in many habitats, such as beaches, swamps, mountains and lowlands. This study aims to determine the bird community in the Bagek Kembar essential ecosystem area, West Lombok Regency. Data was collected using the transect path method (exploration) and point count. The research was conducted in November-December. Observation was carried out in the morning at 06.30- 09.30 and in the afternoon at 15.30-18.30 Central Indonesian Time (GMT +8) with representatives of 3 observation locations: pond area, rehabilitation mangrove and natural mangrove. Data collection was done using transect lines (cruising) and point count. The results showed that there were 57 bird species from 23 families categorised into migratory birds (18 species), protected birds (12 species), and six species of birds categorised as NT (Near Threatened). The results of the abundance index of species included in the highest dominant category are Cerulean Kingfisher (Alcedo coerulescens), with a value of 7.87% found in the pond area. Furthermore, the results of the diversity index of the three areas have a high diversity index value of 3.900.

Environmental changes and historical occupation at Oued Laksar (Ksar Seghir), Morocco

Laksar is a small river near the village of Ksar Seghir, located between Tangier and Ceuta (Morocco), strategic points to control the Strait of Gibraltar over centuries. The river outlets at the western part of a sandy beach that can block the fluvial discharge in years of low precipitation/river flow.The area is densely occupied since the 5th century BC, during the roman period and Early Middle Age in the archaeological site of Dhar d’Aseqfane, located around 1 km from the mouth of the river. The coastal town of Ksar Seghir was founded on the eastern margin and was used as a shipyard for Moroccan dynasties after the 12th century. During the 15th and 16th centuries, Portugal occupied Ksar Seghir to control the Strait and to increase its power in North Africa. After the Portuguese left the site remained abandoned. The present-day Moroccan village developed in the 20th century, first expanding on the western river slope and gradually encompassing the archaeological site.This work aims to i) characterize the environmental evolution of the Laksar River; ii) identify potential records of extreme events such as floods or tsunamis; and iii) explore the relationship between the landscape dynamics and human occupation.To achieve these goals, a ∼5.4 m long sediment core - KS1 - was studied applying high-resolution multiproxy analyses (X-Ray, magnetic susceptibility, sedimentology, organic chemistry and micropalaeontology) together with 14C dating to establish a chronological model.The sedimentary sequence corresponds to intercalations of fine sand and mud. Results point to deposition in subtidal conditions between the core base (ca. 2500 cal BP) and the 15th century AD (388 cm below surface). The dominance of marine foraminifera assemblages with high number of juveniles and high diversity index suggests an environment under open marine conditions during this period. Conversely, the low δ13C values, coupled with the presence of charophytes and Cretaceous, Paleogene and Neogene reworked calcareous nannofossils reflect the contribution of fluvial processes. The sedimentary record underscores fluctuations in fluvial discharge, beach morphology and marine influence. The accumulation of magnetic (heavy) minerals at the core base is the likely result of at least one high-energy event.Following the onset of Portuguese occupation of Ksar Seghir (15th century), the sedimentation rate increases, silting-up the channel margins. Deposition occurs under low subtidal to intertidal conditions. Foraminifera assemblages point to a low salinity environment; coarse materials are mostly constituted by minerogenic particles transported by the fluvial network. Changes in the sedimentary succession (heavy-minerals accumulation, higher marine influence and rip-up clasts) were detected between 219 cm and 140 cm depth below surface that, according to the age-model, overlap temporally with the Lisbon 1755 AD tsunami event (Great Lisbon earthquake).

Refining habitat selection for sulfate-reducing bacteria: Evaluating suitability and adaptability for sulfate-metal wastewater treatment during anaerobic-to-aerobic transitions

Inoculating sulfate-reducing bacteria (SRB) habitats offers an eco-friendly method for treating sulfate-metal laden wastewater, characterized by high sulfate levels, low pH, and elevated heavy metals. This study optimizes source habitat selection of SRB by evaluating groundwater, sewage sludge, and lake sediment, focusing on their suitability and adaptability to aerobic-anaerobic transitions in industrial settings. Sewage sludge, with its slightly acidic pH, reducing environment, and high nutrient levels (Total organic carbon: 207.53 g kg−1, Total nitrogen: 47.12 g kg−1), provides robust SRB potential, as supported by its highest diversity index. However, heavy metals and polycyclic aromatic hydrocarbons pose application challenges. All habitats effectively reduced metal concentrations anaerobically, with Cu removal reaching 95%–99%, and groundwater achieved the highest chemical oxygen demand reduction (63.6%) aerobically. Sludge and sediment showed high biomass and extracellular polymeric substances (EPS) accumulation, while groundwater's nucleic acid-rich EPS enhanced metal immobilization, resulting in stable residual metal forms but with potential remobilization under oxidative conditions. Microbial analysis revealed that Proteobacteria and Firmicutes were key players during transitions, with the highest SRB abundance in groundwater. SRB composition varied across habitats, with Sedimentibacter (13.04%), Desulfovibrio (6.33%), and Desulfomonile (8.1%) dominating in groundwater, sludge, and sediment, respectively, during the anaerobic stage. Functional analysis highlighted sludge's persistence in sulfate reduction under aerobic conditions, while groundwater's limited nitrogen cycle involvement indicated broader biogeochemical limitations. Collectively, these findings highlight strengths and limitations of each habitat as SRB inoculum source, emphasizing the importance of tailored anaerobic-to-aerobic strategies for effective wastewater management.

Accumulation of heavy metals (Cr, Cu, As, Cd, Pb, Zn, Fe, Ni, Co) in the water, soil, and plants collected from Edayar Region, Ernakulam, Kerala, India

The accumulation of heavy metals in the environment is a significant concern due to their potential toxicity and persistence. This study investigates the levels of heavy metal contamination in the water, soil, and plants of the Edayar region in Ernakulam, Kerala, India. The region has experienced industrialization and urbanization, leading to concerns about heavy metal pollution. The study aims to assess the concentrations of chromium (Cr), copper (Cu), arsenic (As), cadmium (Cd), lead (Pb), zinc (Zn), iron (Fe), nickel (Ni), and cobalt (Co) in water, soil, aquatic and terrestrial plants. Samples were collected from various locations within the Edayar region, and Inductively Coupled Plasma Mass Spectrometry (ICP-MS) was conducted to quantify heavy metal concentrations. The findings of this study will contribute to the assessment of heavy metal pollution in the Edayar region. Plants with a high diversity index were taken for analysis from both aquatic and terrestrial habitats. Scoparia dulcis L. seems to specialize in metal accumulation, possibly for protective purposes. Synedrella nodiflora Gaertn demonstrates adaptability to metal-rich environments through robust metal uptake and tolerance mechanisms. Alternanthera philoxeroides (Mart.) Griseb, on the other hand, appears to have developed mechanisms to manage heavy metal exposure. The results indicate significant levels of heavy metal contamination across all samples, with the highest concentrations detected in soil, followed by water and plants. Chromium and lead levels in soil exceeded the permissible limits set by international standards, posing potential risks to human health and the ecosystem. The accumulation patterns in plants varied, with higher bioaccumulation factors observed for zinc and copper, suggesting their preferential uptake. This study highlights the urgent need for remediation strategies and continuous monitoring to mitigate the impact of heavy metal pollution in the Edayar region. The results will help in understanding the environmental impact of human activities.

Seascape Genetics and Distinct Intraspecific Diversification of the Decapod Nephrops norvegicus in the Adriatic Sea.

Norway lobster Nephrops norvegicus, a prized decapod crustacean species, is found at different depths across the East Atlantic Ocean and Mediterranean Sea. Despite management efforts, the stocks are globally characterised as overexploited. In the present study, the impact of biogeographical boundaries on the phylogeographical and demographic population status was investigated within the Adriatic Sea, addressing important genetic indices for decapod functional conservation management. Central Mediterranean, Adriatic Sea A total of 482 individuals of Nephrops divided into the 12 samples were collected across biogeographical range of the Adriatic Sea. Using the mtDNA D-loop and microsatellite markers, methods of phylogeography and seascape genetics were applied to infer offshore versus coastal population divergence, demography and structure. Significant findings include genetic differentiation between offshore and coastal samples, with higher diversity indices in open waters. The limited gene flow observed between these two areas emphasises the self-sustained nature of coastal populations. Recent demographic changes in coastal populations reflect geographical constraints, fishing pressures and fluctuations in self-recruitment success. Additionally, the study reveals historical biogeographic events shaping the Adriatic populations, with evidence suggesting lineage divergence during the upper Pleistocene and postglacial recolonisation from southern Adriatic refugia. The role of biogeographical conditions in shaping genetic structure and limited gene flow between inshore and offshore areas underscore the need for improved management strategies, emphasising the importance of marine protected areas in conserving coastal populations and maintaining overall genetic diversity of the Norway lobster in the Adriatic Sea. Genomic monitoring within current management practices is recommended.

Genetic variation and population structure of Taenia multiceps (Coenurus cerebralis) based on mitochondrial cox1 gene: A comprehensive global analysis

Taenia multiceps is a neglected parasite having veterinary and public health importance. The predilection sites of the parasite larva (Coenurus cerebralis) are brain (cerebral coenurosis) and subcutaneous (non-cerebral coenurosis). There is a dearth of data regarding molecular characterization of T. multiceps and even fewer population structure-based studies on T. multiceps. The current study was conducted to provide epidemiological information regarding the global population structure of the parasite. The NCBI GenBank database was accessed to download the sequences of cox1 gene, which were further subjected to PopArt software to construct median-joining networks. The DnaSp software was used to compute neutrality and diversity indices. Host and region-wise indices of neutrality and diversity were also computed. There were 166 gene sequences found in the NCBI database. Followed by removal of short gene sequences, 143 were considered to perform bioinformatic analyses. A total of 30 haplotypes with 46 mutations and 23 parsimony informative sites were found. High diversity (Hd = 0.889, π = 0.01186) and negative but statistically insignificant neutrality indices (Tajima's D = −1.57659, Fu's Fs = −10.552) were found. Region-wise results revealed highest haplotype diversities in isolates from KSA (Hd = 1.00) followed by Greece and Italy (Hd = 0.962), and China (Hd = 0.931). Host-wise data analysis showed an overall negative Tajima's D value and there exists highest haplotype diversity in cattle (Hd = 1.00) followed by dogs (Hd = 0.833), sheep (Hd = 0.795) and goats (Hd = 0.788). The findings of the study indicate that the population diversity of T. multiceps will increase worldwide as shown by high diversity and negative neutrality indices. The findings of the study significantly add-in to the existing bank of knowledge about population structure of T. multiceps. We recommend conducting more studies employing different genetic markers to better comprehend the epidemiology of the parasite.

Genetic diversity and incidence of cassava bacterial blight (CBB) caused by Xanthomonas phaseoli pv. manihotis in Burkina Faso

AbstractCassava bacterial blight (CBB), caused by Xanthomonas phaseoli pv. manihotis (Xpm), poses a significant threat to cassava production in Burkina Faso. Prior to this study, the geographical distribution, incidence and origin of CBB introductions were poorly understood. In this investigation, we assessed the incidence of CBB in major cassava‐cropping regions and analysed the genetic diversity of 344 Xpm strains collected from 19 fields between 2015 and 2016, using a multilocus variable number of tandem repeat analysis (MLVA) scheme targeting 14 microsatellite markers. Our results reveal the presence of CBB in three out of four cropping regions, with incidences ranging from 0% to 100% at locality and variety scale. Burkina Faso's Xpm strains exhibited high genetic diversity at multiple levels, including country scale (He = 0.6), cropping region (0.43 to 0.57), locality (0.25 to 0.50) and field (0.25 to 0.52). Pairwise comparisons among populations from different cropping areas indicated a strong genetic differentiation. The categorical minimum spanning tree reveals that the Cascades region has the higher diversity indices and consequently could be the origin site of dispersion of Xpm in the other cropping regions of cassava. Human activities play a major role in the dissemination of Xpm through cassava cuttings. The importance of the sanitary state of cuttings must be emphasized in order to avoid CBB and ensure good cassava production.

Analysis Of Plant Diversity Agroforestry In The Mount Lawu Natural Forest Area

The natural forest area of Mount Lawu, with various plant compositions, can be landscaped by humans to produce diverse landscape characters in the natural forest area. The solution for implementing the Agroforestry system is very appropriate because land management with this system is to overcome problems arising from changes in land use and soil and water conservation. The research aims to analyze plant diversity in agroforestry practices with services in natural landscape water conservation and develop strategies in agroforestry services. This research was carried out on the natural forest of Mount Lawu, using the fast AgroBiodiversity Appraisal method. The research results show that the composition of the vegetation structure at the research location varies greatly with a high agroforestry diversity index. The practice of agroforestry in the natural forest of Mount Lawu at an altitude of 1600 above sea level with the highest important index value is dominated by the plant species Arenga pinnata, pine merkusi, and paraserientes falcataria. In the slope area of 2200 meters above sea level, the plant species are dominated by Acacia decurrens, while at an altitude of 2800 meters above sea level, the plant species are dominated by Fuchsia magellanica, Anaphalis javanica, Casuarina junghuniana.

The Diatom Diversity and Ecological Status of a Tufa-Depositing River through eDNA Metabarcoding vs. a Morphological Approach-A Case Study of the Una River (Bosnia and Herzegovina).

Tufa deposits in karst rivers are unique habitats created by mutual interactions between specific environmental and biotope features and inhabited by diatoms as a highly abundant and diverse algal group. This pilot study aimed to investigate the diversity of diatom communities on tufa depositing habitats and assess the Una River's ecological status using a comparative molecular and morphological approach for diatom identification. The 312 base pairs of the rbcL gene were barcoded and analyzed using MiSeq reads and amplicon sequence variants (ASVs) obtained by the DADA2 pipeline. The reference database Diat.barcode v7 was used for taxonomic assignment. The morphological identification of the diatoms was carried out in parallel. In total, the combined dataset revealed 46 taxa identified at genus rank, 125 on the subgenus, and 145 on combined taxonomy rank. The metabarcoding approach mostly leads to a lower number of identified taxa at species rank (58 in molecular vs. 119 in optical inventory), resulting in higher values of beta diversity and heterogeneity in diatom assemblages in samples obtained by morphological approach. Despite the high percentage of taxonomically not assigned diatom ASVs to the species rank, high Shannon diversity index values and a similar number of taxa per locations compared to the morphological approach were obtained. Taxa Achnanthidium minutissimum (Kützing) Czarnecki, Achnanthidium pyrenaicum (Hustedt) H.Kobayasi, Amphora pediculus (Kützing) Grunow, Diatoma vulgaris Bory, Navicula cryptotenella Lange-Bertalot, and Navicula tripunctata (O.F.Müller) Bory were identified at all locations in both inventories. Although limited consistency in the diatom abundances between the two inventory datasets was found, a similar grouping of samples was observed connected to the river's longitudinal gradient. The data obtained using molecular approach in most sites indicated a mostly lower ecological status (good or moderate) compared to the data obtained from the morphological approach (high, good, and moderate). The potential of environmental DNA (eDNA) diatom metabarcoding for water monitoring and diversity studies is undeniable, but to fully realize the benefits of these methods in the future, it is essential to standardize protocols and expand the reference database for species found in specific habitats, such as tufa deposits.

Honey pollen analysis in selected districts of North Wollo zone, Amhara region, Ethiopia

Melissopalynology plays a pivotal role in identifying and managing the geographical and botanical origins of honey. In this study, forty-five honey samples were collected from three potential districts in the North Wollo zone, Ethiopia. The pollen grains of these samples were analyzed using the procedures outlined by the International Commission for Bee Botany (ICBB) to determine the botanical sources of the honey. Among the samples, twenty-five were classified as monofloral, while the remaining twenty were identified as multifloral honey. Nineteen plant species from twelve different plant families were identified as the honey bee floras in the North Wollo zone. The dominant families, representing over 45% of the pollen grains in the samples, were Asteraceae (9 samples), Myrtaceae (5 samples), Papilionaceae (4 samples), Fabaceae (2 samples), Hypericaceae (2 samples), Acanthaceae (1 sample), Brassicaceae (1 sample), and Ericaceae (1 sample). Bidens spp., Trifolium rueppellianum, and Eucalyptus globulus emerged as the top three honey bee floras in terms of relative percentage and frequency. Furthermore, eleven samples exhibited a high diversity index range (H) of 1.56% in Lasta and 1.01% in the Meket districts, while the remaining thirty-four samples showed a lower diversity index ranging from 0.31 to 0.99. Our findings underscore the importance of conserving bee floras to enhance honey production and ensure sustainability in beekeeping practices in the North Wollo Zone.

Efficacy of thymol nanoemulsion against Varroa destructor mites infesting Apis mellifera colonies under the stress of abiotic factors in Egypt

ABSTRACT Varroa destructor is a serious pest threats honey bees health worldwide. This study aims to evaluate the effect of thymol nanoemulsion against Varroa. The experiment comprised four colony groups; control, thymol emulsion (Th) 100 ppm, thymol nanoemulsion (NTh) 50, and NTh 25 ppm. NTh 25 ppm was the most potent with insignificant difference and no correlation with temperature, followed by Th 100 ppm, NTh 50 ppm and control groups with fallen Varroa of 70.45%, 67.59%, 60.08% and 51.49%, respectively. NTh 25 ppm group exhibited moderate candy consumption (45%) when compared to Th 100 ppm (47.35%) and control (52.09%) groups with insignificant differences. The pollen consumption was significantly the highest in the NTh 25 ppm group (41.59%) compared with the NTh 50 ppm (36.73%), Th 100 ppm (33.99%) and control (33.69%) groups. NTh 50 ppm has the lowest fallen Varroa and candy consumption percentages. Thymol nanoparticle size (17.6 nm), high zeta potential (-20.1 mv) and low diversity index (0.383) revealed the thymol nanoemulsion stability. So, NTh 25 ppm may decline residues and thymol sensitivity to temperature and increase affordability by one-quarter. Moreover, pollen consumption increase in NTh 25 ppm may enhance colony immunity.

Transfer versus co-production: Knowledge as ‘MEANS’ to sustainability as an ‘END’

Abstract This study examines the relationship between sustainability performance and knowledge, as well as between innovation transfer and co-production. It moves away from evaluating processes to exploring impact by investigating how explicit and tacit knowledge archetypes are associated with sustainability performance in the agri-food sector. Applying the knowledge-based theory and the Shannon index, we rely on a database from 2013 to 2020 of two case studies selected from a Spanish research institution. At the institutional level, the results postulate that knowledge and innovation transfer tends to have a higher diversity index, mainly driven by explicit knowledge archetype. Tacit type of knowledge in both transfer and co-production mechanisms predominately relies on engagement parameters. At the case study level, as an educational toolkit, the first case study prioritizes engagement that is, transferring and transmitting knowledge to a higher number of participants—tacit knowledge transfer. As an innovative technique, the second case study prioritizes diversity that is, transferring and transmitting knowledge through various channels—explicit knowledge transfer. Regarding sustainability performance, the findings demonstrate that both explicit and tacit knowledge are associated with health and capacity building pillars in the first case study through the transfer mechanism. However, in the second one, tacit knowledge is mainly associated with economic and socioterritorial pillars through transfer and co-production mechanisms. This study sheds light on the micro level of knowledge, proposing an approach for researchers and practitioners to categorize knowledge in different proxies and evaluate their performance.

Hexagonal geospatial model of landscape diversity in the northern sub‐area of the Volga River Delta landscape, Russia

The aim is to analyse the landscape diversity (LD) of the northern sub‐area of the Volga River delta landscape using a series of mathematical operations.The work is based on full‐stack landscape works including field experiments. Descriptive method, GIS‐analysis and remote sensing data were used in the work.A set of landscape diversity indices was calculated for the northern sub‐area of the Volga Delta landscape on the basis of mathematical apparatus and the entropic complexity of landscape pattern (or Shannon diversity index) of the studied region was estimated. The results of the analysis made it possible to identify two habitats with rather high landscape diversity indices in this region.LD is one of the most important geographical characteristics of the region and allows assessment of the stability of geosystems to anthropogenic loads, reflection on the nature of economic development and use of geosystems and their conservation potential. By comparing HR indicators and retrospective analysis of economic development of the Volga River Delta, it was found that areas with low landscape diversity index were more often used for agriculture, as single large tracts are easier to adapt to economic needs. Areas with a complex morphological structure and, accordingly, a high level of landscape diversity are generally not subject to most types of economic impact.

Nature-Based Solutions for Landscape Performance Evaluation—Handan Garden Expo Park’s “Clear as a Drain” Artificial Wetland as an Example

As a technology for water landscape performance that considers landscape, ecological, and social effects, nature-based solutions play a crucial role in enhancing the functionality of integrated ecosystem services on the micro-scale. This study conducted a systematic investigation into the landscape performance of the “Clear as a Drain” composite sponge facility at Handan Garden Expo Park. The following conclusions were drawn: (1) In terms of ecological restoration support services, the “Clear as a Drain” artificial wetland exhibited diverse habitat types, a rich variety of plant species specific to the site’s region, and high plant diversity indices for shrubs (1.776) and herbaceous aquatic plants (3.352). Reclaimed water reused in the artificial terraced wetland promoted plant growth and diversity while contributing to site self-rehabilitation; plants also significantly contributed to carbon fixation, oxygen release, and carbon emission reduction. (2) Regarding ecological restoration regulation services, the artificial wetland effectively purified reclaimed water with substantial improvements observed in incoming water quality during spring, summer, and autumn—particularly notable purification effects were observed during the summer months. Pollutant reduction rates for COD, BOD5 ammonia nitrogen, TP, and TN reached 75.8%, 72.1%, 93.8%, 96.7%, and 90.3%, respectively; different independent subsystems within the wetland demonstrated distinct advantages in pollutant removal; park plants displayed strong air purification capabilities; annual energy savings from park plants could fully cover daily energy consumption for nearby residents. This case could serve as guidance for scientific management and design parameter optimization of other composite sponge facilities.

Biotic regulation of phoD-encoding gene bacteria on organic phosphorus mineralization in lacustrine sediments with distinct trophic levels

Organic phosphorus (Po) mineralization hydrolyzed by alkaline phosphatase (APase) can replenish bioavailable P load in the sediment water ecosystem of lakes. However, the understanding about the interaction between P load and bacteria community encoding APase generation in the sediment are still limited. Different P pools in the sediments from Taihu Lake, China were measured using sequential extraction procedure. The APAase activity (APA) were obtained accompanying with enzymatic dynamical parameters Vmax and Km. The abundances and diversity of gene phoD-harboring bacterial communities were assessed using high throughput sequencing. The analysis results showed the decrease of potentially bioavailable P fractions including MgCl2-P and Fe-P along sampling gradient southwards together with active P concentrations in the water. Conversely, increasing APA and absolute abundance of phoD gene were found with the decreasing of P loads southwards. Positive correlation (p < 0.05) between absolute abundance and APA indicated that phoD-encoding bacteria manipulated the APA and Po mineralization. Negative correlation (p < 0.01) suggested that the APA was restrained by high P load and was promoted under low P condition. However, higher Vmax and Km values suggested that high mineralization potential of Po maintained the high concentrations of potentially bioavailable P even the APA was restricted. The abundance increase of predominant genus Cobetia (from 15.51 to 24.34 %) mirrored by the reduced Calothrix abundance (from 24.65 to 1036 %) was speculated to be responsible for the APA promotion under low P condition. Higher diversity indices in the high P scenario suggested that high P load stimulated the ecological diversity of gene phoD-encoding bacteria community. Generally, rare taxa such as Burkholderia having high connected degrees in bacterial communities together with abundant genera synergistically manipulated the phoD gene abundance and APase generation. Interaction between P fractions and bacteria encoding phoD gene determined the eutrophication status in the lacustrine ecosystem.

Endolithic Fungal Diversity in Antarctic Oligocene Rock Samples Explored Using DNA Metabarcoding.

In this study, we evaluated the fungal diversity present associated with cores of Oligocene rocks using a DNA metabarcoding approach. We detected 940,969 DNA reads grouped into 198 amplicon sequence variants (ASVs) representing the phyla Ascomycota, Basidiomycota, Mortierellomycota, Chytridiomycota, Mucoromycota, Rozellomycota, Blastocladiomycota, Monoblepharomycota, Zoopagomycota, Aphelidiomycota (Fungi) and the fungal-like Oomycota (Stramenopila), in rank abundance order. Pseudogymnoascus pannorum, Penicillium sp., Aspergillus sp., Cladosporium sp., Aspergillaceae sp. and Diaporthaceae sp. were assessed to be dominant taxa, with 22 fungal ASVs displaying intermediate abundance and 170 being minor components of the assigned fungal diversity. The data obtained displayed high diversity indices, while rarefaction indicated that the majority of the diversity was detected. However, the diversity indices varied between the cores analysed. The endolithic fungal community detected using a metabarcoding approach in the Oligocene rock samples examined contains a rich and complex mycobiome comprising taxa with different lifestyles, comparable with the diversity reported in recent studies of a range of Antarctic habitats. Due to the high fungal diversity detected, our results suggest the necessity of further research to develop strategies to isolate these fungi in culture for evolutionary, physiological, and biogeochemical studies, and to assess their potential role in biotechnological applications.