Landfalling typhoons frequently cause severe flooding and socioeconomic losses along the eastern coast of China, yet the relative influence of oceanic and storm-related factors on precipitation variability remains insufficiently understood. This study investigates the relationships among sea surface temperature (SST), translation speed, typhoon intensity, and precipitation characteristics for 23 typhoons that made landfall in Zhejiang Province during 2000–2025. Typhoon track, intensity, precipitation, and SST data were analyzed to examine pre-landfall evolution, precipitation variability across intensity categories, and the environmental factors associated with typhoon-induced precipitation. Results showed that SST generally decreased as typhoon approached the coast, with mean values declining from 27.9 °C offshore to 24.5 °C at landfall. Translation speed exhibited a non-linear evolution during the 120 h preceding landfall, with an average speed of 9.8 km h⁻¹ and a weak positive tendency toward the coast. Peak 24 h precipitation varied considerably among intensity categories. Severe typhoons (STY) produced the highest mean precipitation (120.9 ± 92.3 mm), whereas super typhoons (SuperTY) exhibited lower but more consistent rainfall totals. Correlation analysis revealed a weak relationship between translation speed and rainfall (r = −0.18), indicating that storm motion alone was insufficient to explain rainfall variability. SST showed a moderate negative correlation with rainfall (r = −0.53), highlighting the complex relationship between ocean thermal conditions and precipitation variability. These findings show that typhoon precipitation over Zhejiang is associated with the combined variability of storm intensity, ocean thermal conditions, atmospheric moisture availability, and coastal environmental conditions, providing scientific insights for understanding typhoon-related hazards under climate change.

Background/Objectives: Plant mitogenomes display remarkable variation in size, structure, and gene content, yet their evolutionary causes remain unclear. Araceae, the most significant family within Alismatales, encompasses both aquatic and terrestrial lineages, providing an excellent system for studying how ecological shifts influence mitogenome evolution. Methods: We assembled and annotated four new mitogenomes using both short- and long-read sequencing, including three aquatic taxa (Pistia stratiotes L., Spirodela intermedia W. Koch, Wolffia australiana (Benth.) Hartog & Plas) and one terrestrial species (Amorphophallus konjac K. Koch). Along with five previously published mitogenomes, we performed comparative analyses across nine Araceae species. Results: These mitogenome sizes varied from ~178 kb to ~877 kb, consisting of one to 19 circular molecules, with aquatic species generally having smaller and simpler structures. Plastid-derived sequences (MTPTs) contributed 1.2–10.6% of genome content, peaking in Zantedeschia aethiopica (L.) Spreng. Despite significant structural heterogeneity, all species maintained core respiratory genes under strong purifying selection, while ribosomal protein-coding genes showed lineage-specific loss. RNA editing ranged from 363 to 772 sites per mitogenome, with the number of sites independent of mitogenome size. Conclusions: Overall, this study uncovers the dynamic evolutionary patterns of Araceae mitogenomes and offers a framework for understanding how habitat shifts between aquatic and terrestrial environments influence mitogenome diversity in plants.

Phytoplankton, the primary producers of marine ecosystems, play a crucial role in sustaining primary production. This study investigates spatiotemporal variations in phytoplankton functional groups (PFGs) and their environmental drivers across the Bohai, Yellow, and East China Seas (BYECS) from 2003 to 2022. Sea surface temperature exhibited a significant warming trend (sea surface temperature [SST]; τ > 0.48, p < 0.01), increasing from 16.39°C in 2011 to 17.98°C in 2021, mean at 17.24 ± 0.39°C and a breakpoint around 2009. Smaller phytoplankton, including prokaryotes (PROKAR, 27.86%; mean = 1.59 ± 0.96 mg m−3) and pico-phytoplankton (PICO, 28.99%; mean = 1.70 ± 0.95 mg m−3) showed strong negative correlations with SST (r = −0.64 and −0.69) and pronounced declines after 2015. Haptophytes and nanoplankton also decreased significantly (τ < −0.52, p < 0.001) with a breakpoint around 2011. In contrast, larger groups; diatoms (5.28%; mean = 0.41 ± 0.15 mg m−3) and micro-phytoplankton (MICRO, 8.44%; mean = 0.60 ± 0.19 mg m−3) were positively associated with SST (r = 0.38–0.49), indicating enhanced resilience under warming conditions. Total chlorophyll-a (TChl-a; 3.38 ± 3.74 mg m−3) declined significantly (τ < −0.57, p < 0.001) and showed a strong negative correlation with SST (r = −0.64), indicating reduced biomass after 2011. PICO and MICRO contributed 30–45% and 20–35% of TChl-a, respectively. Nutrients showed no significant long-term trends. Overall, findings reveal a warming-driven shift from small to larger phytoplankton groups, with decrease in TChl-a reflecting structural and productivity changes in the BYECS ecosystem. These findings are BYECS-specific and should be interpreted with caution due to uncertainties in remote-sensing PFG products and the potential influence of riverine inputs, stratification, and mixing.

This study investigates the atmospheric and upper-ocean responses associated with Super Typhoon (TY) Lekima (2019) during 4–12 August, including its landfall over Zhejiang Province, China. Variations in sea surface temperature (SST), latent heat flux (LHF), water vapor flux (WVF), total column water vapor (TCWV), vertical integral moisture divergence (VIMD), mean sea level pressure (MSLP), wind circulation, precipitation, subsurface temperature and salinity, and Ekman pumping velocity (W_E) were analyzed throughout the typhoon life cycle. Before intensification, SSTs of 29.5–31.0 °C indicated favorable ocean-surface conditions. During and after the storm passage, SST decreased to approximately 26.0–27.5 °C along portions of the track and below 25.0 °C near the Zhejiang coast, with stronger cooling on the right-hand side of the track. Surface salinity decreased by approximately 0.3–0.8 PSU during 8–10 August, with freshening extending through the upper 30–40 m. The Ekman pumping field identified regions where wind-stress curl favored upwelling and downwelling, with stronger positive signals occurring on the right side of the track. During the active maritime stage, LHF values of approximately −300 to −200 W m⁻² indicated enhanced upward latent heat transfer. WVF reached 1800–2200 kg m⁻¹ s⁻¹, TCWV exceeded 70 kg m⁻², and VIMD decreased below approximately −100 × 10⁻⁵ kg m⁻² s⁻¹, indicating enhanced moisture transport and convergence. These conditions coincided with daily precipitation exceeding 120 mm and locally reaching approximately 160 mm over northern and northwestern coastal Zhejiang. The minimum daily mean MSLP decreased from 1000 to 972–976 hPa during peak intensity and subsequently increased as Lekima approached landfall and weakened inland. While these responses are qualitatively consistent with previous TY case studies, our study provides new quantitative benchmarks and process attribution through heat budget analysis. This integrated, stage-based analysis provides a comprehensive quantitative reference for model validation and future comparative studies of landfalling typhoons in the western North Pacific.