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The degradation of urban ecology, particularly in metropolitan areas distinguished by dense populations and impervious surfaces, presents a worldwide challenge linked to swift urban expansion. Despite extensive documentation of urbanization's impact on broad regions or specific urban ecosystems over defined time periods, there remains a scarcity of studies investigating the spatiotemporal dynamics of landscape pattern (LP) changes in specific ecosystems at small-to-medium scales within inland megacities as a response to urbanization. Therefore, this work focused on the Bailuwan Wetland Park (BWP) in Chengdu, an inland megacity in southwestern China. Employing satellite imagery data from selected years spanning the previous decade (2010–2021, encompassing 2010, 2012, 2015, 2018, and 2021), this investigation delved into the influences of urbanization on the LP over various time-frames and across different land use/land cover (LULC) types. Our study revealed that urbanization has a significant impact on the patch-/landscape-level characteristics, including the class area (CA), number of patches (NP), patch density (PD), percentage of landscape (PLAND), aggregation index (AI), contagion index (CONTAG), largest patch index (LPI), landscape shape index (LSI), fractal dimension index (FRAC_MN), Shannon's diversity (SHDI), and evenness index (SHEI). Over the period from 2010 to 2021, NP and PD experienced notable increases, while landscape shape (LSI/FRAC_MN) exhibited greater complexity and fragmentation (PLAND) intensified. Further, landscape heterogeneity (AI/CONTAG) and diversity (SHDI/SHEI) decreased. Particularly significant was the conversion of 52 ha of agricultural land to vegetation, resulting in heightened complexity and fragmentation in vegetation patterns. Additionally, the CA of lakes and rivers decreased following the establishment of the park, while the CA and NP of bare land presented significant increases. These findings suggest that rapid urbanization significantly influences the spatial–temporal dynamics of wetland landscape patterns. Consequently, it is imperative for society to prioritize the restoration and protection of urban constructed wetlands. [ABSTRACT FROM AUTHOR]

Inland lake water–air interfaces, particularly the partial pressure of CO2 (pCO2), have become key parameters in the study of global carbon cycle changes. However, there are few studies on short-term daily variations in pCO2 in urbanizing lakes. The fluctuations in pCO2 and CO2 fluxes (fCO2) were monitored biweekly on-site for pCO2 assessments during daytime hours (7:00–17:00 CST) from January to September 2020 in an urbanizing lake located in Southwest China. We found a pronounced and uninterrupted decline in the average levels of pCO2 and fCO2 from 7:00 to 17:00 CST. Notably, the mornings (7:00–12:00 CST) exhibited substantially elevated pCO2 and fCO2 values compared to the afternoons. Specifically, compared to 7:00, the mean pCO2 and fCO2 at 17:00 CST decreased by ca. 74% and 112%, respectively. The average daytime pCO2 was 707 ± 642 μatm, significantly higher than the typical atmospheric CO2 levels of 380–420 μatm, while the average pCO2 on 9 January, 1 April, and 27 July was lower than typical atmospheric CO2. Each month, all water environmental parameters showed significant differences. pCO2 and fCO2 reached maximums in September; water temperature and turbidity significantly increased; and pH, dissolved oxygen and transparency markedly decreased. Additionally, the correlation between pCO2 and environmental factors demonstrated that the nutrient levels, dissolved oxygen, pH, and transparency/turbidity had significant roles in CO2 dynamics in this lake. Therefore, this urbanizing lake could serve as a CO2 source and sink during the daytime. [ABSTRACT FROM AUTHOR]

Prefabricated buildings are the future direction of the construction industry. The carbon reduction in prefabricated buildings has attracted increasing attention due to its importance to low-carbon and energy savings in the construction industry and achieving China's "dual carbon" goal. Although research has been conducted on carbon reduction in prefabricated buildings, the use of cloud models for carbon reduction effect evaluation has not been explored. This study therefore aims to develop a cloud model-based evaluation of the carbon emission reduction effect for prefabricated buildings incorporating the characteristics of prefabricated buildings and the building supply chain. The developed model can support assessments of the whole life cycle phases of a prefabricated building. Firstly, carbon flow analysis is carried out from the perspective of the construction supply chain, and the carbon emission reduction effect evaluation index system of prefabricated buildings is established, which contains 5 guideline layers and 26 carbon emission reduction indicators. Secondly, the Continuous Ordered Weighted Averaging operator (C-OWA) is used to calculate the index weight calculation, and the cloud model is applied to conduct a comprehensive evaluation of the carbon emission reduction effect. Finally, this model is applied to evaluate the carbon emission reduction effect in the case of a building. The case study validated the efficiency of the developed model. This study extends the knowledge of carbon emission reduction by addressing specific characteristics of prefabrication and the construction supply chain. This validated model will enhance the willingness to apply prefabricated buildings to reduce carbon emissions and achieve the "dual carbon" goal. [ABSTRACT FROM AUTHOR]

The WRKY family of transcription factors plays important roles in plant growth and responses to biotic and abiotic stresses. Ammopiptanthus nanus, the only evergreen broadleaf shrub endemic to the desert and semi-desert regions of northwestern China, is highly tolerant to various stresses. However, a systematic study of WRKY proteins in A. nanus has not been reported. In the present study, we identified 63 WRKY genes in the A. nanus genome. Based on the conserved WRKY domains, zinc finger structures, and phylogenetic relationships in their encoded proteins, we classified these genes into four groups (group I–IV) and several subgroups (subgroup IIa–IIe). Conserved motif analysis showed that all motifs except those within the WRKY domains had a subfamily-specific distribution. Expression analysis revealed that the AnWRKY genes had distinct expression patterns, with some being more responsive to herbivory and drought stresses than others. Based on the results of our current study, we speculate that AnWRKY40 and AnWRKY48 are positive regulators of the plant's response to drought and herbivory stresses, respectively. Our results indicate that AnWRKY genes contribute to the ability of A. nanus plants to withstand harsh, dry conditions. [ABSTRACT FROM AUTHOR]

The Songliao Basin is the most productive petroliferous lacustrine basin in NE China, and numerous large gas fields with large proven reserves occur in its deep formations. However, considerable challenges remain: (1) the origins and genetic types of the natural gases are controversial; (2) the gas-source correlations are poorly studied; and (3) the migration distance is vague. In this study, these problems are addressed by the study of the gas compositions, light hydrocarbons, and stable hydrogen and carbon isotopes. The gases are predominantly of organic and thermogenic origins. The Huoshiling (J3h) and Shahezi (K1sh) gases are mainly mixtures of coal-derived and oil-associated gases and the mixed-sources of primary kerogen degradation and secondary oil cracking, while the Yingcheng (K1yc) gases are mainly coal-derived gases and predominantly derived from primary kerogen degradation. The gases in different sags are derived from the source rocks developed in the same sags where the gases accumulated, characterized by the proximal-source accumulation. Vertically, the gases in the J3h and K1sh are predominantly sourced by the proximal J3h and K1sh mudstones, while the gases in the K1yc are mainly derived from either the J3h or the K1sh source rocks, suggesting the gas migration with short distances. [ABSTRACT FROM AUTHOR]

After the implementation of the Coal Replacing Project (CRP) in the northern parts of China in 2017, its effect on PM 2.5 composition is still unclear. In the study, water-soluble ionic components (WSICs) and stable sulfur isotope ratios (δ 34 S) of SO 4 2- in PM 2.5 collected during the domestic heating period before and after the implementation of CRP in Tianjin were analyzed. Results showed that the average concentrations of both PM 2.5 and WSICs have dropped dramatically after the CRP, especially for the SO 4 2- (by approximately 57-60%). After the CRP, the range of δ 34 S sulfate was significantly narrowed to 4.1-7.5‱ in January 2018 and 1.4-6.1‱ in January 2019, which suggested that the sulfur source was becoming simple. It was interesting that the δ 34 S sulfate value in the pollution period before the CRP was higher than that in the clean period, whereas it showed the opposite tendency after the CRP, which implied that the contribution of sea salt was high during the pollution period before the CRP. The MIXSIAR model calculated that the contributions of the transition-metal ion (TMI) oxidation and NO 2 oxidation pathways in the three sampling stages were higher than those of the OH radical oxidation and H 2 O 2 /O 3 oxidation pathways, indicating that the formation pathway of sulfate was mainly dominated by heterogeneous oxidation. Before the CRP, the NO 2 oxidation pathway was the dominant sulfate oxidation pathway during a haze episode, and the TMI oxidation pathway dominated the formation of sulfates after the CRP.

Verrucosispora sp. SCSIO 07399, a rare marine-derived actinomycete, produces a set of ansamycin-like polyketides kendomycin B-D ( 1 - 3 ) which possess potent antibacterial activities and moderate tumor cytotoxicity. Structurally, kendomycin B-D contain a unique aliphatic macrocyclic ansa scaffold in which the highly substituted pyran ring is connected to the quinone moiety. In this work, a type I/type III polyketide synthase (PKS) hybrid biosynthetic gene cluster coding for assembly of kendomycin B ( kmy ), and covering 33 open reading frames, was identified from Verrucosispora sp. SCSIO 07399. The kmy cluster was found to be essential for kendomycin B biosynthesis as verified by gene disruption and heterologous expression. Correspondingly, a biosynthetic pathway was proposed based on bioinformatics, cluster alignments, and previous research. Additionally, the role of type III PKS for generating the precursor unit 3,5-dihydroxybenzoic acid (3,5-DHBA) was demonstrated by chemical complementation, and type I PKS executed the polyketide chain elongation. The kmy cluster was found to contain a positive regulatory gene kmy4 whose regulatory effect was identified using real-time quantitative PCR (RT-qPCR). These advances shed important new insights into kendomycin B biosynthesis and help to set the foundation for further research aimed at understanding and exploiting the carbacylic ansa scaffold.