A conserved gastropod withdrawal circuit in Biomphalaria glabrata, an intermediate host for schistosomiasis.

Neuronal signals mediated by the biogenic amine serotonin (5-HT) underlie critical survival strategies across the animal kingdom. This investigation examined serotonin-like immunoreactive neurons in the cerebral ganglion of the panpulmonate snail Biomphalaria glabrata, a major intermediate host for the trematode parasite Schistosoma mansoni. Five neurons comprising the cerebral serotonergic F (CeSF) cluster of B. glabrata shared morphological characteristics with neurons that contribute to withdrawal behaviors in numerous heterobranch species. The largest member of this group, designated CeSF-1, projected an axon to the tentacle, a major site of threat detection. Intracellular recordings demonstrated repetitive activity and electrical coupling between the bilateral CeSF-1 cells. In semi-intact preparations, the CeSF-1 cells were not responsive to cutaneous stimuli but did respond to photic stimuli. A large FMRF-NH2-like immunoreactive neuron, termed C2, was also located on the dorsal surface of each cerebral hemiganglion near the origin of the tentacular nerve. C2 and CeSF-1 received coincident bouts of inhibitory synaptic input. Moreover, in the presence of 5-HT they both fired rhythmically and in phase. As the CeSF and C2 cells of Biomphalaria share fundamental properties with neurons that participate in withdrawal responses in Nudipleura and Euopisthobranchia, our observations support the proposal that features of this circuit are conserved in the Panpulmonata.NEW & NOTEWORTHY Neuronal signals mediated by the biogenic amine serotonin underlie critical survival strategies across the animal kingdom. This investigation identified a group of serotonergic cells in the panpulmonate snail Biomphalaria glabrata that appear to be homologous to neurons that mediate withdrawal responses in other gastropod taxa. It is proposed that an ancient withdrawal circuit has been highly conserved in three major gastropod lineages.

Different stressors uniquely affect the expression of endocannabinoid-metabolizing enzymes in the central ring ganglia of Lymnaea stagnalis.

The endocannabinoid system (ECS) plays an important role in neuroprotection, neuroplasticity, energy balance, modulation of stress, and inflammatory responses, acting as a critical link between the brain and the body's peripheral regions, while also offering promising potential for novel therapeutic strategies. Unfortunately, in humans, pharmacological inhibitors of different ECS enzymes have led to mixed results in both preclinical and clinical studies. As the ECS has been highly conserved throughout the eukaryotic lineage, the use of invertebrate model organisms like the pond snail Lymnaea stagnalis may provide a flexible tool to unravel unexplored functions of the ECS at the cellular, synaptic, and behavioral levels. In this study, starting from the available genome and transcriptome of L. stagnalis, we first identified putative transcripts of all ECS enzymes containing an open reading frame. Each predicted protein possessed a high degree of sequence conservation to known orthologues of other invertebrate and vertebrate organisms. Sequences were confirmed by qualitative PCR and sequencing. Then, we investigated the transcriptional effects induced by different stress conditions (i.e., bacterial LPS injection, predator scent, food deprivation, and acute heat shock) on the expression levels of the enzymes of the ECS in Lymnaea's central ring ganglia. Our results suggest that in Lymnaea as in rodents, the ECS is involved in mediating inflammatory and anxiety-like responses, promoting energy balance, and responding to acute stressors. To our knowledge, this study offers the most comprehensive analysis so far of the ECS in an invertebrate model organism.

Losses and destabilization of soil organic carbon stocks in coastal wetlands converted into aquaculture ponds.

Coastal-wetlands play a crucial role as carbon (C) reservoirs on Earth due to their C pool composition and functional sink, making them significant for mitigating global climate change. However, due to the development and utilization of wetland resources, many wetlands have been transformed into other land-use types. The current study focuses on the alterations in soil organic-C (SOC) in coastal-wetlands following reclamation into aquaculture ponds. We conducted sampling at 11 different coastal-wetlands along the tropical to temperate regions of the China coast. Each site included two community types, one with solely native species (Suaeda salsa, Phragmites australis and Mangroves) and the other with an adjacent reclaimed aquaculture pond. Across these 11 locations we compared SOC stock, active OC fractions, and soil physicochemical properties between coastal wetlands and aquaculture ponds. We observed that different soil uses, sampling sites, and their interaction had significant effects on SOC and its stock (p < .05). Reclamation significantly declined SOC concentration at depths of 0-15 cm and 15-30 cm by 35.5% and 30.3%, respectively, and also decreased SOC stock at 0-15 cm and 15-30 cm depths by 29.1% and 37.9%, respectively. Similar trends were evident for SOC stock, labile organic-C, dissolved organic-C and microbial biomass organic-C concentrations (p < .05), indicating soil C-destabilization and losses from soil following conversion. Soils in aquaculture ponds exhibited higher bulk density (BD; 11.3%) and lower levels of salinity (61.0%), soil water content (SWC; 11.7%), total nitrogen (TN) concentration (23.8%) and available-nitrogen concentration (37.7%; p < .05) than coastal-wetlands. Redundancy-analysis revealed that pH, BD and TN concentration were the key variables most linked with temporal variations in SOC fractions and stock between two land use types. This study provides a theoretical basis for the rational utilization and management of wetland resources, the achievement of an environment-friendly society, and the preservation of multiple service functions within wetland ecosystems.

Roseateles subflavus sp. nov. and Roseateles aquae sp. nov., isolated from artificial pond water and Roseateles violae sp. nov., isolated from a Viola mandshurica root.

Two novel strains, designated APW6T and APW11T, were isolated from artificial pond water, and one novel strain, designated PFR6T, was isolated from a Viola mandshurica root. These strains were found to be Gram-negative, rod-shaped, motile by means of flagella, and oxidase-positive. Growth conditions of the type strains were as follows: APW6T, 15-43 °C (optimum, 28 °C), pH 6.0-12.0 (optimum, pH 7.0), with no salinity; APW11T, 4-35 °C (optimum, 25 °C), pH 6.0-11.0 (optimum, pH 9.0), with 0-1 % NaCl (w/v, optimum 0 %); PFR6T, 10-38 °C (optimum 28 °C), pH 6.0-12.0 (optimum, pH 7.0), with 0-2 % NaCl (w/v; optimum, 0 %). Strains APW6T, APW11T, and PFR6T belonged to the genus Roseateles, having the most 16S rRNA gene sequence similarity to Roseateles saccharophilus DSM 654T (98.1 %), Roseateles oligotrophus CHU3T (98.7 %), and Roseateles puraquae CCUG 52769T (98.1 %). The estimated genome sizes of APW6T, APW11T, and PFR6T were 50 50 473, 56 70 008, and 52 16 869 bp, respectively and the G+C contents were 69.5, 66, and 68.5 mol%. The digital DNA-DNA hybridization, average amino acid identity, and average nucleotide identity values among the novel strains and related taxa were all lower than 22.4, 74.7, and 78.9 %, respectively. The predominant cellular fatty acids (>10 %) of all strains were summed feature 3 (comprising C16 : 1 ω6c and/or C16 : 1 ω7c) and C16 : 0. PFR6T also had summed feature 8 (comprising C18 :  1 ω7c and/or C18 :  1 ω6c) as a major fatty acid. The polar lipid profile of all strains contained phosphatidylethanolamine, phosphoaminoglycolipid, and phosphoglycolipid. The distinct phylogenetic, physiological, and chemotaxonomic features reported in this study indicate that strains APW6T, APW11T, and PFR6T represent novel species within the genus Roseateles, for which the names Roseateles subflavus sp. nov., with the type strain APW6T (=KACC 22877T=TBRC 16606T), Roseateles aquae sp. nov., with the type strain APW11T (=KACC 22878T=TBRC 16607T), and Roseateles violae sp. nov (=KACC 23257T=TBRC 17653T) are respectively proposed.

Paucibacter sediminis sp. nov., isolated from sediment in a freshwater pond.

A Gram-stain-negative, aerobic, oxidase-positive, weakly catalase-positive, motile by means of a single polar flagellum, rod-shaped bacterium designated as strain S2-9T was isolated from sediment sampled in Wiyang pond, Republic of Korea. Growth of this strain was observed at 10-40 °C (optimum, 35 °C) and pH 5.5-9.5 (optimum, pH 7.0-8.0) and in the presence of 0-0.5 % NaCl in Reasoner's 2A broth. The major fatty acids (>10 %) of strain S2-9T were C16 : 0 and summed feature 3 (comprising a mixture of C16 : 1 ω7c and/or C16 : 1 ω6c). Ubiquinone-8 was detected as the respiratory quinone. The major polar lipids were phosphatidylethanolamine and phosphatidylglycerol. Strain S2-9T showed the highest 16S rRNA gene sequence similarity to Paucibacter oligotrophus CHU3T (98.7 %), followed by 'Paucibacter aquatile' CR182 (98.4 %), all type strains of Pelomonas species (98.1-98.3 %), Mitsuaria chitosanitabida NBRC 102408T (97.9 %), Kinneretia asaccharophila KIN192T (97.8 %), Mitsuaria chitinivorans HWN-4T (97.4 %), and Paucibacter toxinivorans 2C20T (97.4 %). Phylogenetic trees based on the 16S rRNA gene and whole-genome sequences showed that strain S2-9T formed a tight phylogenetic lineage with Paucibacter species (CHU3T, CR182, and 2C20T). Average nucleotide identity and digital DNA-DNA hybridization values between strain S2-9T and Paucibacter strains were 76.6-79.3% and 19.5-21.5 %, respectively. The genomic DNA G+C content of strain S2-9T was 68.3 mol%. Notably, genes responsible for both sulphur oxidation and reduction and denitrification were found in the genome of strain S2-9T, suggesting that strain S2-9T is involved in the nitrogen and sulphur cycles in pond ecosystems. Based on the polyphasic taxonomic results, strain S2-9T represents a novel species of the genus Paucibacter, for which the name Paucibacter sediminis sp. nov. is proposed. The type strain is S2-9T (= KACC 22267T= JCM 34541T).

Chitiniphilus purpureus sp. nov., a novel chitin-degrading bacterium isolated from crawfish pond sediment.

A novel Gram-stain-negative, curved rod-shaped, motile and chitin-degrading strain, designated CD1T, was isolated from crawfish pond sediment in Caidian District (30° 58' N 114° 03' E), Wuhan City, Hubei Province, PR China. Growth of this strain was observed at 15-40°C (optimum between 28 and 30 °C), at pH 7.0-9.0 (optimum between pH 7.0 and 8.0) and with 0-1 % (w/v) NaCl (optimum at 0 %). With respect to the 16S rRNA gene sequences, strain CD1T had the highest similarity (96.91-97.25 %) to four type strains of the genera 'Chitinolyticbacter' and Chitiniphilus within the family Chitinibacteraceae. The phylogenetic trees based on genome sequences and 16S rRNA gene sequences indicated that strain CD1T was close to members of these two genera, in particular to the genus Chitiniphilus. The genomic DNA G+C content of strain CD1T was 64.8 mol%. The average nucleotide identity and the Genome-to-Genome Distance Calculator results showed low relatedness (below 95 and 70 %, respectively) between strain CD1T and the closely related type strains. Ubiquinone-8 was the predominant quinone. The major cellular fatty acids were C10 : 0, C16 : 0, summed feature 3 (C16 : 1 ω7c and/or C16 : 1 ω6c) and summed feature 8 (C18 : 1 ω7c and/or C18 : 1 ω6c). The polar lipid profile was composed of a mixture of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, four unidentified lipids, two unidentified phospholipids, two unidentified aminolipids and an unidentified aminoglycolipid. On the basis of the evidences presented in this study, strain CD1T represents a novel species of the genus Chitiniphilus, for which the name Chitiniphilus purpureus sp. nov. is proposed, with strain CD1T (=CCTCC AB 2022395T=KCTC 92850T) as the type strain.

Poly-ß-hydroxybutyrate production by Synechocystis MT_a24 in a raceway pond using urban wastewater.

Poly-ß-hydroxybutyrate (PHB) is a potential source of biodegradable plastics that are environmentally friendly due to their complete degradation to water and carbon dioxide. This study aimed to investigate PHB production in the cyanobacterium Synechocystis sp. PCC6714 MT_a24 in an outdoor bioreactor using urban wastewater as a sole nutrient source. The culture was grown in a thin-layer raceway pond with a working volume of 100 L, reaching a biomass density of up to 3.5 g L-1 of cell dry weight (CDW). The maximum PHB content was found under nutrient-limiting conditions in the late stationary phase, reaching 23.7 ± 2.2% PHB per CDW. These data are one of the highest reported for photosynthetic production of PHB by cyanobacteria, moreover using urban wastewater in pilot-scale cultivation which multiplies the potential of sustainable cultivation approaches. Contamination by grazers (Poterioochromonas malhamensis) was managed by culturing Synechocystis in a highly alkaline environment (pH about 10.5) which did not significantly affect the culture growth. Furthermore, the strain MT_a24 showed significant wastewater nutrient remediation removing about 72% of nitrogen and 67% of phosphorus. These trials demonstrate that the photosynthetic production of PHB by Synechocystis sp. PCC6714 MT_a24 in the outdoor thin-layer bioreactor using urban wastewater and ambient carbon dioxide. It shows a promising approach for the cost-effective and sustainable production of biodegradable carbon-negative plastics. KEY POINTS: • High PHB production by cyanobacteria in outdoor raceway pond • Urban wastewater used as a sole source of nutrients for phototrophic growth • Potential for cost-effective and sustainable production of biodegradable plastics.

Empathic forecasting of the big-fish-little-pond effect.

The big-fish-little-pond effect (BFLPE) is the tendency for students to evaluate themselves more favourably when they have high rank in a low rank school than low rank in a high rank school. Research has documented the BFLPE on experienced emotions. We conducted three studies that examined forecasts of how the BFLPE influences other people's emotions (i.e. empathic forecasts). In Study 1, participants received performance feedback about themselves or another person and reported their own affect or anticipated the other person's affect. Results extended the BFLPE to empathic forecasting. Moreover, forecasters anticipated that the BFLPE had a stronger influence on negative emotion than it actually did. Study 2 tested whether neglect of group rank underlies the BFLPE in empathic forecasting. Empathic forecasts were strongly influenced by another person's rank in their group, but only weakly influenced by group rank. Study 3 tested whether extremity of group ranks exacerbates the BFLPE in empathic forecasting. Empathic forecasts were especially favourable (unfavourable) when a target had very high (low) rank in a very low (high) rank group. These data support the BFLPE in empathic forecasting, but also illustrate ways in which it is both similar to and different from actual experience of the effect.

Retrospect on the Ground Deformation Process and Potential Triggering Mechanism of the Traditional Steel Production Base in Laiwu with ALOS PALSAR and Sentinel-1 SAR Sensors.

The realization of a harmonious relationship between the natural environment and economic development has always been the unremitting pursuit of traditional mineral resource-based cities. With rich reserves of iron and coal ore resources, Laiwu has become an important steel production base in Shandong Province in China, after several decades of industrial development. However, some serious environmental problems have occurred with the quick development of local steel industries, with ground subsidence and consequent secondary disasters as the most representative ones. To better evaluate possible ground collapse risk, comprehensive approaches incorporating the common deformation monitoring with small-baseline subset (SBAS)-synthetic aperture radar interferometry (InSAR) technique, environmental factors analysis, and risk evaluation are designed here with ALOS PALSAR and Sentinel-1 SAR observations. A retrospect on the ground deformation process indicates that ground deformation has largely decreased by around 51.57% in area but increased on average by around -5.4 mm/year in magnitude over the observation period of Sentinel-1 (30 July 2015 to 22 August 2022), compared to that of ALOS PALSAR (17 January 2007 to 28 October 2010). To better reveal the potential triggering mechanism, environmental factors are also utilized and conjointly analyzed with the ground deformation time series. These analysis results indicate that the ground deformation signals are highly correlated with human industrial activities, such underground mining, and the operation of manual infrastructures (landfill, tailing pond, and so on). In addition, the evaluation demonstrates that the area with potential collapse risk (levels of medium, high, and extremely high) occupies around 8.19 km2, approximately 0.86% of the whole study region. This study sheds a bright light on the safety guarantee for the industrial operation and the ecologically friendly urban development of traditional steel production industrial cities in China.

Enhancing microalgae biomass production: Exploring improved scraping frequency in a hybrid cultivation system.

Recently, hybrid systems, such as those incorporating high-rate algal ponds (HRAPs) and biofilm reactors (BRs), have shown promise in treating domestic wastewater while cultivating microalgae. In this context, the objective of the present study was to determine an improved scraping frequency to maximize microalgae biomass productivity in a mix of industrial (fruit-based juice production) and domestic wastewater. The mix was set to balance the carbon/nitrogen ratio. The scraping strategy involved maintaining 1 cm wide stripes to retain an inoculum in the reactor. Three scraping frequencies (2, 4, and 6 days) were evaluated. The findings indicate that a scraping frequency of each 2 days provided the highest biomass productivity (18.75 g total volatile solids m-2 d-1). The species' behavior varied with frequency: Chlorella vulgaris was abundant at 6-day intervals, whereas Tetradesmus obliquus favored shorter intervals. Biomass from more frequent scraping demonstrated a higher lipid content (15.45%). Extrapolymeric substance production was also highest at the 2-day frequency. Concerning wastewater treatment, the system removed 93% of dissolved organic carbon and ∼100% of ammoniacal nitrogen. Combining industrial and domestic wastewater sources to balance the carbon/nitrogen ratio enhanced treatment efficiency and biomass yield. This study highlights the potential of adjusting scraping frequencies in hybrid systems for improved wastewater treatment and microalgae production.

Enhancing environmental performance in biogas production from wastewater-grown microalgae: A life cycle assessment perspective.

The production of biogas from microalgae has gained attention due to their rapid growth, CO2 sequestration, and minimal land use. This study uses life cycle assessment to assess the environmental impacts of biogas production from wastewater-grown microalgae through anaerobic digestion within an optimized microalgae-based system. Using SimaPro® 9 software, 3 scenarios were modeled considering the ReCiPe v1.13 midpoint and endpoint methods for environmental impact assessment in different categories. In the baseline scenario (S1), a hypothetical system for biogas production was considered, consisting of a high rate algal pond (HRAP), a settling, an anaerobic digester, and a biogas upgrading unit. The second scenario (S2) included strategies to enhance biogas yield, namely co-digestion and thermal pre-treatment. The third scenario (S3), besides considering the strategies of S2, proposed the biogas upgrading in the HRAP and the digestate recovery as a biofertilizer. After normalization, human carcinogenic toxicity was the most positively affected category due to water use in the cultivation step, accounted as avoided product. However, this category was also the most negatively affected by the impacts of the digester heating energy. Anaerobic digestion was the most impactful step, constituting on average 60.37% of total impacts. Scenario S3 performed better environmentally, primarily due to the integration of biogas upgrading within the cultivation reactor and digestate use as a biofertilizer. Sensitivity analysis highlighted methane yield's importance, showing potential for an 11.28% reduction in ionizing radiation impacts with a 10% increase. Comparing S3 biogas with natural gas, the resource scarcity impact was reduced sixfold, but the human health impact was 23 times higher in S3.

Performance enhancement, bacterial communities optimization and emerging pollutants elimination by microalgal-bacterial consortium for treating aquaculture pond sediments.

Aquaculture pond sediments have a notable influence on the ecosystem balance and farmed animal health. In this study, microalgal-bacterial immobilization (MBI) was designed to improve aquaculture pond sediments via synergistic interactions. The physicochemical characteristics, bacterial communities, and the removal efficiencies of emerging pollutants were systematically investigated. The consortium containing diatom Navicula seminulum and Alcaligenes faecalis was cultivated and established in the free and immobilized forms for evaluating the treatment performance. The results indicated that the immobilized group exhibited superior performance in controlling nutrient pollutants, shaping and optimizing the bacterial community compositions with the enrichment of functional bacteria. Additionally, it showed a stronger positive correlation between the bacterial community shifts and nutrient pollutants removal compared to free cells. Furthermore, the immobilized system maintained the higher removal performance of emerging pollutants (heavy metals, antibiotics, and pathogenic Vibrios) than free group. These findings confirmed that the employment of immobilized N. seminulum and A. faecalis produced more synergistic benefits and exerted more improvements than free cells in ameliorating aquaculture pond sediments, suggesting the potential for engineering application of functional microalgal-bacterial consortium in aquaculture.

Assessment of heavy metal levels in polyculture fish farms and their aquatic ecosystems: an integrative study addressing environmental and human health risks associated with dam water usage.

This study examines the levels of heavy metals in polyculture fish (Labeo rohita, Cyprinus carpio, and Catla catla), water, and sediment in Tanda Dam, Kohat, Pakistan, aiming to understand environmental and health risks. Samples of fish, water, and sediment were collected from 3 fish farms, and heavy metal concentrations were measured using a Flame Atomic Absorption Spectrophotometer (AAS). Results reveal that C. catla exhibited significantly higher (p < 0.05) levels of Zn than other fish species. Conversely, C. carpio showed significantly higher (p < 0.05) concentrations of Pb, Cd, Cr, Mn, Cu, As, and Ni than other species. The heavy metal hierarchy in C. carpio was found to be Zn > Cu > Pb > Cr > Cd > Mn > As > Ni. While heavy metal levels in L. rohita and C. catla generally fell within reference ranges, exceptions were noted for Zn, Pb, and Cd. Conversely, in C. carpio, all metals exceeded reference ranges except for Cu and Ni. Principal Component Analysis (PCA) indicated a close relationship between water and sediment. Additionally, cluster analysis suggested that C. catla formed a distinct cluster from L. rohita and C. carpio, implying different responses to the environment. Despite concerns raised by the Geoaccumulation Index (Igeo) and Contamination Factor (CF), particularly for Cd, which exhibited a high CF. Furthermore, Hazard Index (HI) values for all three fish species were below 1, suggesting low health risks. However, elevated Igeo and CF values for Cd suggest significant pollution originating from anthropogenic sources. This study underscores the importance of monitoring heavy metals in water for both environmental preservation and human health protection. Future research efforts should prioritize pollution control measures to ensure ecosystem and public health safety.

From Sea Water to Salt Crystals: An Onsite Investigation of Microplastics in a Conventional Sea Salt Farming System.

This study investigated microplastic (MP) contamination in conventional sea salt farming systems. Various crude sea salt samples (n = 22) that were traditionally produced were collected from salt farms and local vendors. Salt water (n = 15), macroalgae (n = 6), and clay of pond floors (n = 6) were collected from ponds subjected to different production (stabilization, evaporation, and concentration and crystallization concentration) processes. All samples were analyzed for MP abundance and characteristics. The potential sources of MP contamination in the salt were also investigated. The mean abundance of MPs in the salt water and clay of pond floor increased progressively throughout the production process and reached its highest level in the concentration and crystallization ponds (7400 MP particles/m3 in salt water and 19,336 MP particles/m2 in the clay of the pond floor). A maximum of 26,500 MP particles/kg of macroalgal material indicated the potential sink of MPs on the surface of the algae. Approximately 34-2377 MP particles/kg salt were found in the crude sea salt samples. However, the mean abundance (378 MP particles/kg of salt) indicated nonsignificant impacts of different harvesting processes on MP contamination. Most MP size distributions, shapes and polymer types in the salts were similar to those found in the salt water, macroalgae and clay of the pond floor. Approximately 99% of the MPs were fragments that were suspected to be decomposed from larger plastic debris and plastic machinery and tools used at the salt farm. Similar patterns of polymer distribution, in which PP > PE > PET > PS, were found for all samples studied.

Metagenomic investigations into the microbial consortia, degradation pathways, and enzyme systems involved in the biodegradation of plastics in a tropical lentic pond sediment.

The exploitation of exciting features of plastics for diverse applications has resulted in significant plastic waste generation, which negatively impacts environmental compartments, metabolic processes, and the well-being of aquatic ecosystems biota. A shotgun metagenomic approach was deployed to investigate the microbial consortia, degradation pathways, and enzyme systems involved in the degradation of plastics in a tropical lentic pond sediment (APS). Functional annotation of the APS proteome (ORFs) using the PlasticDB database revealed annotation of 1015 proteins of enzymes such as depolymerase, esterase, lipase, hydrolase, nitrobenzylesterase, chitinase, carboxylesterase, polyesterase, oxidoreductase, polyamidase, PETase, MHETase, laccase, alkane monooxygenase, among others involved in the depolymerization of the plastic polymers. It also revealed that polyethylene glycol (PEG), polyhydroxyalkanoates (PHA), polyhydroxybutyrate (PHB), polylactic acid (PLA), polybutylene adipate terephthalate (PBAT), polyethylene terephthalate (PET), and nylon have the highest number of annotated enzymes. Further annotation using the KEGG GhostKOALA revealed that except for terephthalate, all the other degradation products of the plastic polymers depolymerization such as glyoxylate, adipate, succinate, 1,4-butanediol, ethylene glycol, lactate, and acetaldehyde were further metabolized to intermediates of the tricarboxylic acid cycle. Taxonomic characterization of the annotated proteins using the AAI Profiler and BLASTP revealed that Pseudomonadota members dominate most plastic types, followed by Actinomycetota and Acidobacteriota. The study reveals novel plastic degraders from diverse phyla hitherto not reported to be involved in plastic degradation. This suggests that plastic pollution in aquatic environments is prevalent with well-adapted degrading communities and could be the silver lining in mitigating the impacts of plastic pollution in aquatic environments.

Microplastic pollution and ecological risk assessment of a pond ecosystem.

Microplastic (MP) pollution has been observed in various ecosystems as a result of the rapid increase in plastic production over the past half-century. Nevertheless, the extent of MP pollution in different ecosystems, particularly in freshwater ecosystems, has not been well-studied, and there are limited investigations on this particular topic, specifically in Türkiye. Here, we quantify the occurrence and distribution of MPs in surface water samples collected from Topçu Pond (Türkiye) for the first time. Water samples were collected at five stations and filtered (30 L for each station) through stacked stainless steel sieves (5 mm, 328 µm, and 61 µm mesh size) with a diameter of 30 cm. The abundance, size, color, shape, and type of collected debris samples were analyzed after the wet peroxide oxidation process. MP particles were observed in all samples at an average abundance of 2.4 MPs/L. The most abundant MP size class and type were 0-999 µm and fiber respectively. On the other hand, prevalent colors were black and colorless in general. According to the Raman analysis results, the identified MP derivatives were polypropylene (40%), polyamide (30%), ethylene acrylic acid (20%), and polyvinylchloride (10%). Moreover, the pollution load index (PLI) index was used to determine the pollution status. PLI values were determined as 1.91 at station S1, 1.73 at station S2, 1.31 at station S3, 1 at station S4 and 1.24 at station S5. The PLI value determined for the overall pond was 1.4. The results of this research show that MP pollution is present in Topçu Pond and contributes to the expanding literature on MP pollution in pond ecosystems.

Transformation of coastal wetlands in the Sundarban Delta (1999-2020).

Spanning across Bangladesh and India, the Sundarban Delta consists of over a thousand islands, the majority of which are protected. These islands are important for the rich biodiversity and unique species found here. However, these islands are also at the forefront of climate change due to the impact of rising sea levels and extreme weather events. Therefore, we analyzed the long-term transformations in the land use land cover (LULC) between 1999 and 2020. We used a variety of geostatistical methods, including optimized hot spots cold spots and join count statistics, to examine the spatial patterns of changes in LULC across the study area. The results of our analysis revealed substantial changes in the spatial patterns of mangroves and pond aquaculture. The changes revealed a distinct north-south demarcation in spatial patterns, in the form of clustering of mangroves in the uninhabited islands located in the south and pond aquaculture clustered in the northern inhabited islands. The loss of area under mangroves was concentrated in the southern edges of the islands, which were most exposed to erosion in the open ocean. Nevertheless, we observed an increase in the area under mangroves in some of the northern riverine islands (17 km2). In the case of pond aquaculture, it was mostly concentrated in inhabited islands in the north. Most of the expansions were concentrated in the Indian part of the delta (631 km2). It is noteworthy that because of effective conservation measures, there was very limited overlap between mangroves and pond aquaculture, denoting the conversion of agricultural land to pond aquaculture instead of mangroves. Thus, the results of our study revealed the importance of local level conservation policies and anthropogenic activities, such as deforestation and local level disturbance like over-extraction of water and pollution, on the changing patterns of LULC across this unique, fragile ecosystem. Future studies may incorporate a finer resolution time series of LULC changes over time and space to enable more detailed analysis.

Copper Stress Causes Shell Morphology Changes in Early Juvenile Anodonta woodiana Based on Geometric-Morphometric Analysis.

In this study, the morphological characteristics of early juvenile shells of Anodonta woodiana, which were exposed to different concentrations of aqueous copper, were analyzed using 10 landmarks to determine morphological changes in the shells. Morphological changes mainly occurred at the top of the shell and front and back ends of the central axis. Stepwise discriminant analysis proved shape differences among experimental and control groups. The results of this study demonstrate for the first time that environmentally relevant copper concentrations cause stress-related morphological changes in A. woodiana in the vulnerable early juvenile stage.

Developmental environment has lasting effects on amphibian post-metamorphic behavior and thermal physiology.

Environmental challenges early in development can result in complex phenotypic trade-offs and long-term effects on individual physiology, performance and behavior, with implications for disease and predation risk. We examined the effects of simulated pond drying and elevated water temperatures on development, growth, thermal physiology and behavior in a North American amphibian, Rana sphenocephala. Tadpoles were raised in outdoor mesocosms under warming and drying regimes based on projected climatic conditions in 2070. We predicted that amphibians experiencing the rapid pond drying and elevated pond temperatures associated with climate change would accelerate development, be smaller at metamorphosis and demonstrate long-term differences in physiology and exploratory behavior post-metamorphosis. Although both drying and warming accelerated development and reduced survival to metamorphosis, only drying resulted in smaller animals at metamorphosis. Around 1 month post-metamorphosis, animals from the control treatment jumped relatively farther at high temperatures in jumping trials. In addition, across all treatments, frogs with shorter larval periods had lower critical thermal minima and maxima. We also found that developing under warming and drying resulted in a less exploratory behavioral phenotype, and that drying resulted in higher selected temperatures in a thermal gradient. Furthermore, behavior predicted thermal preference, with less exploratory animals selecting higher temperatures. Our results underscore the multi-faceted effects of early developmental environments on behavioral and physiological phenotypes later in life. Thermal preference can influence disease risk through behavioral thermoregulation, and exploratory behavior may increase risk of predation or pathogen encounter. Thus, climatic stressors during development may mediate amphibian exposure and susceptibility to predators and pathogens into later life stages.

Streptomyces beihaiensis sp. nov., a chitin-degrading actinobacterium, isolated from shrimp pond soil.

A Gram-stain-positive actinobacterium, designated strain GXMU-J5T, was isolated from a sample of shrimp pond soil collected in Tieshangang Saltern, Beihai, PR China. The morphological, chemotaxonomic and phylogenetic characteristics were consistent with its classification in the genus Streptomyces. The organism formed an extensively branched substrate mycelium, with abundant aerial hyphae that differentiated into spores. Phylogenetic analysis of 16S rRNA gene sequences showed that strain GXMU-J5T was most related to Streptomyces kunmingensis DSM 41681T (similarity 97.74 %) and Streptomyces endophyticus YIM 65594T (similarity 96.80 %). However, the values of digital DNA-DNA hybridization, average nucleotide identity and evolutionary distance of multilocus sequence analysis between strain GXMU-J5T and its closest relatives indicated that it represented a distinct species. Strain GXMU-J5T contained ll-diaminopimelic acid and the major whole-cell hydrolysates were xylose and galactose. The predominant menaquinones of strain GXMU-J5T were revealed as MK-9(H4), MK-9(H6) and MK-9(H8). The polar lipids consisted of diphosphatidylglycerol, phosphatidylmethylethanolamine, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylinositol mannosides and phospholipids of unknown structure containing glucosamine. The predominant cellular fatty acids were iso-C15 : 0, anteiso-C15 : 0, iso-C16 : 0, iso-C17 : 0 and anteiso-C17 : 0. The whole genome size of strain GXMU-J5T was 6.79 Mbp with a 71.39 mol% G+C content. Genomic analysis indicated that strain GXMU-J5T had the potential to degrade chitin. On the basis of these genotypic and phenotypic data, it is supported that strain GXMU-J5T represents a novel species of the genus Streptomyces, for which the name Streptomyces beihaiensis sp. nov. is proposed. The type strain is strain GXMU-J5T (=MCCC 1K08064T=JCM 35629T).