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Vegetation cover is crucial for ecosystem stability, responding sensitively to climate change and human activities, and is prone to irreversible degradation. However, the mechanisms driving vegetation variations due to natural and anthropogenic factors still need to be fully understood. This study focused on the Weihe River Basin to elucidate the response mechanism of vegetation cover change to climate change and human activities from 2001 to 2020. Long time‐series multi‐source data were combined with a pixel dichotomy model, Theil–Sen median trend analysis, and Mann‐Kendall test to examine the trends and delineate five gradients in vegetation cover change. Additionally, Extreme Gradient Boosting, the Shapley value, and a structural equation model were employed to investigate the multidimensional response of vegetation cover in the basin as a whole and different vegetation cover gradients. The results revealed a general upward trend in vegetation coverage in the Weihe River Basin from 2001 to 2020. Topographic conditions and human activities were identified as primary influencers. Notably, accounting for climate change, particularly about changes in maximum climatic variables, was found to be essential, with temperature changes exerting a greater impact on vegetation cover variations compared to precipitation changes. The interaction between human activities, climate change, and topographic conditions can alter the intensity of each factor's effect. The direction of indicators mentioned above varied across the vegetation cover gradients, emphasizing the need for localized strategies to improve vegetation. These findings offer valuable insights into ecological protection and vegetation restoration in the Weihe River Basin. Plain Language Summary: Understanding how vegetation cover responds to climate change and human influence is vital for maintaining ecosystem health. This study focused on the Weihe River Basin, a region prone to ecological fragility, to explore how vegetation cover responds to human activity and climate change factors, considering basic topographical factors. Models that can identify trends, rank contributions, explore interactions between variables, and quantify the direct and indirect effects of variables were utilized. By analyzing various data and using different models, we found that vegetation coverage generally increased over this period. Factors such as topography and human activities greatly influenced vegetation cover change. Surprisingly, temperature fluctuations had a more substantial impact on vegetation cover than changes in precipitation. Moreover, the interaction between human activities, climate change, and topography can change the intensity and direction of the factor's effect on vegetation cover change. The effects varied across areas with different vegetation cover change conditions of the basin. These findings provide valuable insights for guiding ecological protection and vegetation restoration efforts in the Weihe River Basin. Key Points: Single factor's effect intensity and direction on vegetation cover change changed under the interaction with othersThe impact of extreme climatic conditions on the dynamics of vegetation coverage should not be overlookedThe intensity and direction of the impact of factors varied in diverse vegetation gradients [ABSTRACT FROM AUTHOR]

Based on the modulated electronic properties of Fe3O4-graphene (Fe3O4/GN composite) as well as the outstanding complexation between Pb2+ and natural substances garlic extract (GE), a novel electrochemical sensor for the determination of Pb2+ in wastewater was prepared by immobilization of Fe3O4/GN composite integrated with GE onto the surface of glassy carbon electrode (GCE). Fe3O4/GN composite was employed as an electrochemical active probe for enhancing electrical response by facilitating charge transfer while GE was used to improve the selectivity and sensitivity of the proposed sensor to Pb2+ assay. The electrochemical sensing performance toward Pb2+ was appraised by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and square wave voltammetry (SWV). Under the optimized condition, the sensor exhibited two dynamic linear ranges (LDR) including 0.001 to 0.5 nM and 0.5 to 1000 nM with excellent low detection limit (LOD) of 0.0123 pM (S/N = 3) and quantification limit (LOQ) of 0.41 pM (S/N = 10). Meanwhile, it displayed remarkable stability, reproducibility (RSD of 3.61%, n = 3), and selectivity toward the assay for the 100-fold higher concentration of other heavy metal ions. Furthermore, the novel sensor has been successfully employed to detect Pb2+ from real water samples with satisfactory results. [ABSTRACT FROM AUTHOR]

Combined mutagenesis is widely applied for the breeding of robust Yarrowia lipolytica used in the production of erythritol. However, the changes of genome after mutagenesis remains unclear. This study aimed to unravel the mechanism involved in the improved erythritol synthesis of CA20 and the evolutionary relationship between different Y. lipolytica by comparative genomics analysis. The results showed that the genome size of Y. lipolytica CA20 was 20,420,510 bp, with a GC content of 48.97%. There were 6330 CDS and 649 ncRNA (non-coding RNA) in CA20 genome. Average nucleotide identity (ANI) analysis showed that CA20 genome possessed high similarity (ANI > 99.50%) with other Y. lipolytica strains, while phylogenetic analysis displayed that CA20 was classified together with Y. lipolytica IBT 446 and Y. lipolytica H222. CA20 shared 5342 core orthologous genes with the 8 strains while harbored 65 specific genes that mainly participated in the substrate and protein transport processes. CA20 contained 166 genes coding for carbohydrate-active enzymes (CAZymes), which was more than that found in other strains (108－137). Notably, 4, 2, and 13 different enzymes belonging to glycoside hydrolases (GHs), glycosyltransferases (GTs), and carbohydrate esterases (CEs), respectively, were only found in CA20. The enzymes involved in the metabolic pathway of erythritol were highly conserved in Y. lipolytica , except for transaldolase (TAL1). In addition, the titer and productivity of erythritol by CA20 were 190.97 g/L and 1.33 g/L/h, respectively, which were significantly higher than that of WT5 wherein 128.61 g/L and 0.92 g/L/h were obtained ( P < 0.001). Five frameshift mutation genes and 15 genes harboring nonsynonymous mutation were found in CA20 compared with that of WT5. Most of these genes were involved in the cell division, cell wall synthesis, protein synthesis, and protein homeostasis maintenance. These findings suggested that the genome of Y. lipolytica is conserved during evolution, and the variance of living environment is one important factor leading to genome divergence. The varied number of CAZymes existed in Y. lipolytica is one factor that contributes to the performance difference. The increased synthesis of erythritol by Y. lipolytica CA20 is correlated with the improvement of the stability of cell structure and internal environment. The results of this study provide a basis for the directional breeding of robust strains used in erythritol production.