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Our findings suggest that SOC served as a deep trait due to it negative correlation with deeper branches of phylogenetic clustering, while nitrate functioned as a shallow trait due to its positive correlation with phylogenetic clustering at finer branches. Soil salinity acted as a complex trait effected on both finer and deeper branches. Further potential functional gene co-occurrence network analysis revealed that land reclamation induced shifts of metabolic function by altering the functional gene connectivity. We found that the photosynthesis pathway was enriched in hub modules related to oil field (OF), while methane metabolism was enriched in hub modules linked to sea cucumber pond (CP1). In addition, two-component systems (TCS) were enriched with nitrate, ammonia, SOC and salinity-related modules. Therefore, our study highlights the importance of integrating multi-function and multi-process identification and prediction of coastal diverse reclamation impacts on coastal ecosystems. Extensive and improper overuse of antibiotics resulted in the prevalence of antibiotic resistance genes (ARGs). As the typical semi-enclosed continental shelf sea, the Bohai Sea has been considered as one of the most polluted marine areas in China. However, no comprehensive investigation on the spatial distribution of ARGs in sediments from the Bohai Sea has been reported. A large-scale sampling was performed in the Bohai Sea areas. The abundances of ARGs (6 classes, 29 ARG subtypes), class 1 integron-integrase gene (intI1), hmt-DNA and 16S rRNA gene were evaluated. IntI1 was detected with higher abundances in coastal areas ranging from 2.8 × 105 to 2.5 × 108 copies/g. The total ARGs abundances varied over 3 orders of magnitude in different sampling sites with the maximum at 4.9 × 108 copies/g. Sulfonamides resistance genes were ubiquitous and abundant with the abundances ranging from 5.7 × 104 to 1.8 × 107 copies/g, and quinolones resistance genes varied greatly in different samples. The contour map demonstrated that ARGs were more abundant in the Laizhou Bay, the south of Bohai Bay and the eastern of central sea basin. Most of the target ARG subtypes were detected with 100% detection frequencies. The genes of sul1, sul2 and tetX were detected with both higher absolute and relative abundance, while the abundance of β-lactams ARG subtypes was lower. Principal component analysis (PCA) and redundancy analysis (RDA) indicated that no significant differences in the ARGs abundance existed in different samples, and the sediment qualities played important roles in the distribution of ARGs. Bacterial communities were investigated and 768 strong and significant connections between ARGs and bacteria were identified. The possible hosts of ARGs were revealed by network analysis with higher relative abundance in coastal areas than the sea. The phosphorus (P) supply is mismatched with rice demand in the early and late stages of rice growth, which primarily results in low P use efficiency and high environmental risk. In recent years, the use of the natural periphyton in nutrient regulation in paddy fields has attracted much research interest. However, a mechanistic understanding of the action of periphyton on P biogeochemical cycling during the pivotal stages of rice growth has received little attention. In this study, the influence of periphyton proliferation on the soil surface and its consequential decomposition on P migration and bioavailability were investigated in two paddy soils using two microcosm experiments. Mavoglurant manufacturer The results showed that periphyton rapidly accumulated fertilizer P when it proliferated on the soil surface under favorable light condition, which led to more fertilizer P being stored on the soil surface and less P being fixed by soil particles or transported via runoff into the water bodies. The decomposition of periphyton under unfavorable light condition not only increased soil soluble reactive P, but also increased the amount of easily available P species, such as labile P, AlP, FeP, and mobilized OP. Thus, periphyton colonizing the soil surface in the early stage of rice growth could act as a P sink and decrease the P environmental risk, and its decomposition in the late stage of rice growth could act as a P source and activator. Phosphorus bioavailability regulated by periphyton could be synchronous with rice needs. Thus, periphyton has the potential to increase P use efficiency in paddy fields. Underwater light attenuation plays an important role in modulating aquatic ecosystems and is considered a sentinel of climate change and human activity. However, knowledge of the long-term exposure of underwater ultraviolet radiation (UVR) in aquatic ecosystem is still very limited. We carried out extensive UVR measurements in different seasons in five lakes at different altitudes, collected long-term Secchi disk depth (SDD) data, developed the models between UVR diffuse attenuation coefficient (Kd) and SDD, and further assessed the long-term underwater UVR exposure. Observation results from five lakes including 259 samples showed large spatial variabilities of Kd(313) (UVB) from 0.83 to 5.91 m-1 and Kd(340) (UVA) from 0.51 to 4.67 m-1. Chromophoric dissolved organic matter (CDOM) absorption coefficients were significantly correlated with Kd(313) and Kd(340). Thus, the effects of climate change and human activity on CDOM abundance, source and composition may significantly alter UVR attenuation in aquatic environments. The long-term underwater UVR exposure, which was estimated from significant positive correlations between 1/SDD and Kd(313) and Kd(340), and incident UVR, significantly decreased in Lake Fuxianhu, Lake Erhai, and Lake Qiandaohu. The regime shift from clear water state to turbid state in Lake Erhai around 2001-2003 dramatically decreased underwater UVR exposure. In conclusion, increasing UVR attenuation played a more important role in determining underwater UVR exposure than decreasing incident UVR with the relative contributions of 89.9% and 87.7% in Lake Fuxianhu, 98.0% and 97.7% in Lake Erhai, 94.4% and 92.5% in Lake Qiandaohu for UVB and UVA exposure, respectively. This is the first study to elucidate the long-term trend of underwater UVR exposure considering both increasing UVR attenuation and decreasing incident UVR.

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