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Abstract Background The effects of biodiversity on community function and services are frequently studied in the history of ecology, while the response of individual species to biodiversity remains great elusive. In this study, we determined the biodiversity effects on community productivity as well as species level plant mass and carbon (C) and nitrogen (N) metabolism of eight submerged plants. These macrophytes in Lake Erhai were selected and planted in a water depth of one meter along a diversity gradient of 1, 2, 4 or 8 species. Then, the community productivity or species level plant mass, soluble protein, free amino acid and soluble carbohydrate were correlated to species richness to determine the biodiversity effects on community and single species. Results The results showed that the community level biomass was positively correlated to plant species richness although the species level plant mass of individual species responded differently to the overall plant species richness. Namely, only one plant mass positively correlated to species richness and the others decreased or showed no significant correlation with the increase of species richness. The soluble proteins of most macrophytes were positively correlated to species richness; however, both the free amino acid and soluble carbohydrate of the plants were negatively or not significantly correlated to species richness. Conclusions These results indicated that the selection effects might dominate in our aquatic communities and the negative impacts of biodiversity on C and N metabolism of the macrophytes increased with the increase of species richness, which might result from the strong competition among the studied species. The biodiversity effects on the plant mass, and C and N metabolism of individual submerged species were first reported in this study, while more such field and control experiments deserve further research.

The relationship between diversity and productivity (DPR) is a hot topic in ecology, whereas most evidence comes from studies of manipulated terrestrial ecosystems or from two-dimensional space views. In this study, we determined DPR of submerged plants in a natural mesotrophic lake, Lake Erhai, along its water depth in 2013 and 2019. Our results demonstrated that the community productivity was significantly negatively correlated with plant biodiversity from a three-dimensional space view (all of the water depths) in Lake Erhai due to strong competition effects among submerged species. However, DPR patterns at each water depth (from two-dimensional space views) were various, which might be because these DPR patterns were disturbed by many biotic and abiotic factors or their interplays. Both total biomass and biomass of dominant species negatively correlated with species richness. Moreover, total biomass was positively correlated with biomasses of dominant species. Accordingly, we can presume that DPR patterns are largely determined by relationships between biomasses of dominant species and biodiversity in our study. Our results showed that species number in 2019 was generally smaller than that in 2013 and submerged species were migrating from deep water to shallow water with lake eutrophication in such a short time. Accordingly, measurements should be conducted quickly to control the eutrophication process of Lake Erhai to improve its multiple valuable functions and services.

The roles that adventitious roots play in flooding tolerance have been well-studied in willows, while which of the maximum height of adventitious roots and the abundance of adventitious roots in willows is more important for their flooding tolerance is not well known. In this study, we analyzed the effects of adventitious roots on the flooding tolerance of Salix cavaleriei by comparing the maximum height of adventitious roots and the abundance of adventitious roots in dead and live willows along a flooding gradient from 0 to 180 cm in Lake Erhai, China. The results showed that willow mortality increased drastically when the water depth suffered by willows exceeded 100 cm. Live willows developed more adventitious roots and produced them higher on the trees compared with dead willows, however, the pest infestation percentage of the dead willows was larger. Additionally, both the maximum height and the abundance of adventitious roots in live willows were significantly correlated with water depth, whereas in dead willows, these variables were not significantly correlated or only weakly correlated with water depth. The results indicate that producing adventitious roots higher on the trees may be more important than developing abundant adventitious roots lower on the trees when S. cavaleriei is subjected to high flooding levels. Our data highlight that a faster adventitious root response promotes this species’ survival under flood stress, although pest infestation accounts for a small percentage of willow mortality. Accordingly, we should choose those willows that can develop more abundant adventitious roots and higher on the stems to plant in regions with abrupt water-level fluctuations.

Currently, the reported vancomycin (VCM) aptamers, including the 3- (K d  =  9.13 × 10 -6 m) and 4-truncated variants (K d = 45.5 × 10 -6 m), are engineered via stem truncation of the VCM parent aptamer, which inevitably compromises their affinities, thus affecting their clinical application within the VCM therapeutic window of 6.9-13.8 × 10 -6 m. Herein, the binding pocket of the VCM parent aptamer is elucidated for the first time and we implemented the Post-SELEX modification strategy involving truncation and mutagenesis to refined the VCM parent aptamer. This yielded a VCM aptamer (ABC20-11) with an intramolecular G-triplex, an enhanced thioflavin T (ThT) fluorescence intensity, and an improved affinity (K d = 0.591 × 10 -6 m) and specificity (one-methyl level) for VCM. Utilizing a portable fluorescence detector specifically designed for rapidly detecting VCM concentration and leveraging the competitive binding between VCM and ThT to ABC20-11, a label-free fluorescent aptasensor is developed. This aptasensor exhibits exceptional analytical performances across various clinical samples (serum, cerebrospinal fluid, and joint fluid), with corresponding linear ranges of 0.5-50, 0.5-40, and 0.5-50 × 10 -6 m and detection limits at 0.11, 0.12, and 0.16 × 10 -6 m, respectively. Consequently, the proposed VCM aptasensor displays considerable clinical value and potential for use in rapid VCM detection., (© 2024 Wiley‐VCH GmbH.)

Understanding the strength of trade-off and synergistic relationships among ecosystem services (ESs) is crucial for ecological management and restoration in the Fenhe River Basin. However, there is still a lack of sufficient research on the driving variables and spatial pattern optimization of the strength of ESs relationships in this area. Based on the quantitative assessment of six ESs in the Fenhe River Basin in 2000 and 2020, the ecosystem services trade-off synergy index (TSI) was introduced to quantitatively measure the strength of trade-off and synergistic relationships between each pair of ESs. A Bayesian network was constructed to identify the driving variables of trade-off and synergistic relationships, and sensitivity analysis was conducted to determine the degree of influence of key variables on the strength of these relationships. The optimization area of the strength of ESs trade-off and synergistic relationships was characterized in spatial patterns. The results showed that:① There were significant spatiotemporal differences in the six ESs in the Fenhe River Basin in 2000 and 2020. In terms of time scale, water yield, net primary productivity, crop productivity, soil conservation, and carbon storage all showed a trend of fluctuating increase. In terms of spatial scale, the spatial distribution changes in the six ESs were relatively small over the 20 years. ② The TSI of carbon storage was high in the surrounding area and low in the middle, showing a four-high and four-low pattern. The areas with the highest TSI between grain supply and other services were distributed from north to south. ③ Sensitivity analysis found that the strength of water yield, soil conservation, and habitat quality were significantly affected by precipitation, plant root depth restriction, and rainfall erosion. According to the conditional probability of different states of key variables, Wenshui County, Qingxu County, and Qi County in the central part of the Fenhe River Basin were identified as high-value areas for trade-off and synergistic relationships, which could be used as key areas for ecological restoration. These findings have important theoretical and practical significance for understanding the complex relationship between multiple ESs trade-off and synergistic relationships and their driving variables and for proposing sustainable ecological environment management policies.