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Microplastics are considered to be a widespread environmental contaminant, posing a serious threat to the aquatic environment. We addressed this issue based on field observations and laboratory analysis of samples from Poyang Lake. We collected sediment samples from 10 sites across Poyang Lake during 2017. Data were analyzed by one-way analysis of variance (ANOVA). Results showed that the abundance of microplastics ranged from 11 to 3,153 items/kg dw in the sediment samples. Except at Nanjishan, the amount of microplastics in different periods decreased in the order: December > April > July. Microplastics with a size <1 mm were the most abundant fraction in sediments, reaching over 50%. Observations under microscope revealed four types of microplastics in Poyang Lake: fragments, films, foams and fibers. Fragments were more common in sediments. Microplastics have complex surface topography, typically including rough surfaces, porous structures, cracks and extensive damage. Energy dispersive X-ray analysis indicated that most microplastics contained Si, Na, Ca, Cl and Al. Overall, the results provided strong evidence of high levels of microplastics in Poyang Lake, suggested that the microplastics pollution status in Poyang Lake should continue to be monitored.

Sphagnum bogs possess irreplaceable ecological and economic value, and they are scarce in China, with a fragmented distribution. Based on 19 high-resolution bioclimatic environmental datasets and 71 bog center point locations, we employed a maximum entropy model (MaxEnt) to reconstruct and predict the spatial-temporal geographical distribution patterns of Sphagnum bogs from the last interglacial (LIG) period to two typical CO2 representative concentration pathway scenarios (RCP2.6, RCP8.5) in the future. We further computed the migratory paths of the distribution center points. Finally, a jackknife test was used to uncover the crucial environmental factors restricting the geographical distribution of the bogs. Our data indicated that the MaxEnt niche model had a high simulation precision with an area under the ROC curve value of 0.957. Spatially, the suitable bog habitats are currently centralized in northeastern China, including the Greater Khingan Mountains, the Lesser Khingan Mountains, and the Changbai Mountains, as well as peripheral areas of the Sichuan Basin. Temporally, the contours of Sphagnum bogs were similar to the present and rendered from the last glacial maximum (LMG) period, and had much more total area than the current. The total area in LIG was nearly the same as the current because of the similar climate. It was worth noting that there would be a reduction of the total area in the future. Loss of area occurred at the edges of bogs, especially under RCP8.5. The distribution center of bogs will shift to the northwest in the immediate future. The precipitation of driest month, the mean temperature of warmest quarter and the precipitation of warmest quarter were identified as crucial climatic factors affecting the distribution of Sphagnum bogs. Overall, our research provides scientific evidence for the long-term protection and effective management of these rare, precious natural resources and suggestions for in situ conservation.

Gut microbiota are integral to host health and ecological adaptation, yet their interactions with environmental microbial communities remain understudied in migratory waterbirds. Using high-throughput 16S rRNA gene sequencing, we compared gut microbiota of captive and wild Siberian cranes and their associations with soil microbiota in the Poyang Lake wetlands. Alpha diversity was significantly higher in soil than in gut microbiota, with captive cranes exhibiting greater microbial richness and evenness than wild individuals. Beta diversity analysis revealed distinct gut and soil microbiota, with partial overlap between captive and wild crane gut microbiota. Firmicutes dominated gut communities, with Ligilactobacillus and Romboutsia enriched in captive cranes, whereas Acidobacteria were predominant in soil. Escherichia-Shigella was more abundant in wild cranes and soil. Linear discriminant analysis (LDA) effect size (LEfSe) analysis identified 34 differentially enriched taxa, and microbial network analysis indicated stronger gut–soil microbial associations than those between captive and wild hosts. Network analysis further revealed distinct co-occurrence patterns between captive and wild groups, suggesting potential shifts in microbial interaction structures under different living conditions. These findings provide preliminary insights that may inform future conservation strategies for Siberian cranes.

To address yttrium (Y) contamination from ion adsorption mining, this study developed a combined microbial phytoremediation strategy for dual objectives: ensuring crop safety in and enhancing Y recovery by . Two specific microbial consortia were constructed from rare earth tailings isolates: inoculant I (bacterial: sp., sp., sp.) applied to , and inoculant II (fungal: sp., sp., sp.) applied to . Inoculant I increased biomass by 26% while reducing Y content in roots and rhizosphere soil solution by 47% and 56%, respectively, potentially through down-regulation of amino acid metabolites. Inoculant II increased Y content in the rhizosphere soil solution by 89%, linked to up-regulation of organic acids and coumarin derivatives. Both consortia reduced plant stress markers and enhanced soil enzyme activities. These findings demonstrate that specialized microbial consortia can differentially regulate Y behavior in the rhizosphere-immobilizing it in a crop for food safety, while enhancing its bioavailability for a hyperaccumulator-offering a targeted strategy for managing rare earth element-contaminated agricultural soils.

Taxonomic bias is a well-known shortcoming of species occurrence databases. Understanding the causes of taxonomic bias facilitates future biological surveys and addresses current knowledge gaps. Here, we investigate the main drivers of taxonomic bias in occurrence data of angiosperm species in China. We used a database including 5,936,768 records for 28,968 angiosperm species derived from herbarium specimens and literature sources. Generalized additive models (GAMs) were applied to investigate explanatory powers of 17 variables on the variation in record numbers of species. Five explanatory variables were selected for a multi-predictor GAM that explained 69% of the variation in record numbers: plant height, range size, elevational range, numbers of scientific publications and web pages. Range size was the most important predictor in the model and positively correlated with number of records. Morphological and phenological traits and social-economic factors including economic values and conservation status had weak explanatory powers on record numbers of plant species, which differs from the findings in animals, suggesting that causes of taxonomic bias in occurrence databases may vary between taxonomic groups. Our results suggest that future floristic surveys in China should more focus on range-restricted and socially or scientifically less “interesting” species.

Human-induced changes in landscapes are one of the major drivers of wetland loss and degradation. The Poyang Lake wetland in China has been experiencing severe degradation due to human disturbance and landscape modification. Indicators to assess the condition of this wetland are thus needed urgently. Here, a landscape-based multi-metric index (LMI) is developed to evaluate the condition of the Poyang Lake wetland. Twenty-three candidate metrics that have been applied to wetland health assessment in published studies were tested. Metrics that show strong discriminative power to identify reference and impaired sites, having significant correlations with either benthic macroinvertebrate- or vegetation-based indices of biotic integrity (B-IBI or V-IBI), were chosen to form the LMI index. Five of these metrics (largest patch index, modified normalized differential built-up index, Shannon’s diversity index, connectance index, and cultivated land stress index) were selected as our LMI metrics. A 2 km buffer zone around sample sites had the strongest explanatory power of any spatial scale on IBIs, suggesting that protecting landscapes at local scales is essential for wetland conservation. The LMI scores ranged between 1.05 and 5.00, with a mean of 3.25, suggesting that the condition of the Poyang Lake wetland is currently in the “fair” category. The areas along lakeshores were mainly in poor or very poor conditions, while the less accessible inner areas were in better conditions. This study demonstrates significant links between landscape characteristics and wetland biotic integrity, which validates the utility of satellite imagery-derived data in assessing wetland health. The LMI method developed in this study can be used by land managers to quickly assess broad regions of the Poyang Lake wetland.

Microplastics (MPs), a new type of environmental pollutant, can serve as substrates for microbes. Wetland ecosystems support a diverse range of aquatic and terrestrial species, and their ecological functions can be disturbed by inputs of microplastic debris. However, limited studies have focused on the interactions between MPs and microbes in wetland ecosystems. In this study, the bacterial communities on MPs in the wetland ecosystem of Poyang Lake, China’s largest freshwater lake, were investigated based on 16S rRNA sequencing. We found that the bacterial communities on MPs showed a lower richness and diversity but presented a higher number of unique OTUs than the water and sediment bacterial communities. Furthermore, the structure of the bacterial communities on MPs had a higher similarity to the bacterial compositions of the sediment than of the water, indicating that sediments are an important source of bacteria for MPs. It should be noted that the MPs could enhance the exchange of bacteria between water and sediment. The bacterial composition varied significantly among different substrates and at different sampling times; nevertheless, it showed consistency on the surface of MPs at different sampling sites. Proteobacteria dominated as the most abundant bacterial phylum across all samples. At the genus level, Pseudomonas were distinctly enriched in bacterial communities on MPs. In addition, the results of pathway prediction indicated that the pathways of “human disease” from MPs bacterial communities were higher than those from water and sediment. These results illustrate that the surfaces of MPs serve as distinct habitats for specific bacteria. Environmental factors such as nitrate nitrogen, pH, and organic matter were crucial in shaping the bacterial communities. This study provided a new insight into interactions between MPs and microbes in wetland ecosystems and into the associated potential risks to human health.

Based on the investigation of the species and frequency of submerged plants in Nanjishan Wetland of Poyang Lake in the winter of 2013,chlorophyll contents and photosynthetic fluorescence characteristics of the dominant submerged plants were studied using chlorophyll fluorescence imaging method. The results indicate that the major submerged plants of Nanjishan Wetland in Poyang Lake in winter included Hydrilla verticillata,Vallisneria natans,Najas minor,Potamogeton pectinatus,Nymphoides peltatum,Myriophyllum verticillatum and so on,and the dominant species were mainly H. verticillata and V. natans in different submerged plant communities. The chlorophyll content of H. verticillata is higher than that of V.natans,and the photosynthesis intensity of H. verticillata is stronger than that of V. natans. The value of Ca / Cb of H. verticillata is not large,which shows that the light-harvesting capacity of H. verticillata＇s chlorophyll is considerable in different sampling sites. The highest value of QY-max of V.natans is up to 0. 732,while the lowest value is only 0. 465; the highest value of QY-max of H. verticillata is 0. 677,while the lowest value is 0. 556.All values of QY-max of the submerged plants were lower than 0. 8,which shows that the submerged plants in Nanjishan Wetland of Poyang Lake may be subjected to certain external stress,which indicates that the external stress might cause some damage for the PSII reaction centers.

Floristic composition of the evergreen broad-leaved forest in Jiulianshan Mountain was analyzed based on field investigations and community ecology. The community is rich in species diversity, with 144 spermatophyte families including 379 genera and 647 species, in which there are 6 gymnosperm families including 8 genera and 9 species, 21 monocotyledon families including 77 genera and 116 species, and 117 dicotyledon families including 294 genera and 522 species. Dominant families of the flora are Fagaceae, Lauraceae, Aquifoliaceae, Rosaceae, Ternstroemiaceae, Theaceae, Rubiaceae, Moraceae and Euphoarbiaceae, most of which are of tropical & subtropical distribution. As for family systematic distribution, the ratio of tropical & subtropical to temperate genera is 100:62.8 in 142 genera of 16 families. As for generic distribution in field investigation data, the tropical & subtropical areal type accounts for the majority of genera, in which there are 205 genera belonging to the tropical & subtropical areal type, 131 genera belonging to the temperate areal type, 35 genera belonging to the cosmopolitan areal type and 8 genera belonging to the endemic-to-China areal type. The ratio of the tropical & subtropical to temperate genera was 100:63.9. Floristic composition of the evergreen forest community in Jiulianshan and the typical species of the zonal flora will provide a scientific foundation for stand rehabilitation and stand establishment approximating a natural evergreen broad-leaved forest community. This study also indicates that the sample data based on community research are valid and convenient for floristic and environmental analysis of the evergreen broad-leaved forest community from the Jiulianshan Mountain.

In this review, we discuss the role of microtubule-associated protein 1 B （MAP1B） and its phosphorylation in axonal development and regeneration in the central nervous system. MAP1B exhibits similar functions during axonal development and regeneration. MAP1B and phosphorylated MAPIB in neurons and axons maintain a dynamic balance between cytoskeletal components, and regulate the stability and interaction of microtubules and actin to promote axonal growth, neural connectivity and regeneration in the central nervous system.