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To assess the abilities of global climate models (GCMs) on simulating the spatiotemporal distribution of marine heatwaves (MHWs), GCMs from the Coupled Model Intercomparison Program in Phase 6 (CMIP6) were evaluated from a historical period between 1985 and 2014 in the Northwest Pacific Ocean using a dataset that synthesizes remote sensing data. MHW simulation capabilities were assessed using Rank Score (RS) and Comprehensive Rating (MR) metrics that include both spatial and temporal scoring metrics. It was found that most CMIP6 models overestimate cumulative intensity, while mean and maximum intensities, in addition to the duration, were underestimated in the historical period. Possible future changes in MHWs were also examined based on the rank-based weighting ensembles under four shared socioeconomic pathways (SSPs) scenarios (SSP1-2.6, SSP2-4.5, SSP3-7.0, and SSP5-8.5). MHWs were identified using both a fixed 30-year baseline and a 30-year sliding baseline. In all scenarios, all MHWs metrics except frequency will have an increasing trend for the fixed baseline method. The frequency of MHWs will decrease after the 2050s. Days will first increase and then stabilize under various scenarios. MHWs will take place for more than 300 days by the end of the 21st century for the SSP5-8.5 scenario. The cumulative intensity in the SSP5-8.5 scenario is roughly six times higher than that in the SSP1-2.6 scenario by the end of the 21st century. A fixed baseline will result in near-permanent MHWs at the end of the 21st century. There will be no permanent MHWs at the end of the 21st century. Using the 30-year shifting baseline to define the MHWs can improve future MHW projections by capturing the spatiotemporal variability features of the MHWs. [ABSTRACT FROM AUTHOR]

Accurate estimation of root-zone soil moisture (SM) is of great significance for accurate irrigation management. This study was purposed to identify planted-by-planted mapping of root-zone SM on three critical fruit growth periods based on UAV multispectral images using three machine learning (ML) algorithms in a kiwifruit orchard in Shaanxi, China. Several spectral variables were selected based on variable importance (VIP) rankings, including reflectance Ri at wavelengths 560, 668, 740, and 842 nm. Results indicated that the VIP method effectively reduced 42 vegetation indexes (VIs) to less than 7 with an evaluation accuracy of root-zone SM models. Compared with deep root-zone SM models (SM40 and SM60), shallow root-zone SM models (SM10, SM20, and SM30) have better performance (R2 from 0.65 to 0.82, RRMSE from 0.02 to 0.03, MAE from 0.20 to 0.54) in the three fruit growth stages. Among three ML algorithms, random forest models were recommended for simulating kiwi root-zone SM during the critical fruit growth period. Overall, the proposed planted-by-planted root-zone SM estimation approach can be considered a great tool to upgrade the toolbox of the growers in site-specific field management for the high spatiotemporal resolution of SM maps. [ABSTRACT FROM AUTHOR]

Haze is the phenomenon of visibility degradation caused by extinction effects related to the physicochemical properties of atmospheric particulate matter (APM). Atmosphere heterogeneous reactions can alter the physicochemical properties of APM. Therefore, it is important to understand the atmospheric heterogeneous reactions of APM in order to reveal the cause of haze. Herein, the current situation, developmental trend, source, and composition of APM pollution in China are reviewed. Additionally, we introduce the reaction characteristics and key chemical processes of common inorganic, organic, and mixed pollutant gases on the surface of mineral particles. The effects of mineral particulate matter on aggregation, regulation, and catalysis in the formation of atmospheric aerosols and the synergistic reaction mechanism of SO2, NO2, O3, and VOCs on the surfaces of different mineral particles are summarized. The problems existing in the current research on heterogeneous reactions on the surfaces of mineral particles are also evaluated. This paper aims to gain a deep understanding of the mechanism of mineral particulate matter promoting the formation of secondary aerosols and attempts to provide theoretical support for effective haze control. [ABSTRACT FROM AUTHOR]

Membrane microdomains are nano-scale domains (10–200 nm) enriched in sterols and sphingolipids. They have many important biological functions, including vesicle transport, endocytosis, and pathogen invasion. A previous study reported that the membrane microdomain-associated protein Flotillin1 (Flot1) was involved in plant development in Arabidopsis thaliana; however, whether sterols affect the plant immunity conveyed by Flot1 is unknown. Here, we showed that the root length in sterol-deficient cyclopropylsterol isomerase 1 (cpi1-1) mutants expressing Flot1 was significantly shorter than in control seedlings. The cotyledon epidermal cells in cpi1-1 mutants expressing Flot1 were smaller than in controls. Moreover, variable-angle total internal reflection fluorescence microscopy (VA-TIRFM) and single-particle tracking (SPT) analysis demonstrated that the long-distance Flot1-GFP movement was decreased significantly in cpi1-1 mutants compared with the control seedlings. Meanwhile, the value of the diffusion coefficient Ĝ was dramatically decreased in cpi1-1 mutants after flagelin22 (flg22) treatment compared with the control seedlings, indicating that sterols affect the lateral mobility of Flot1-GFP within the plasma membrane. Importantly, using confocal microscopy, we determined that the endocytosis of Flot1-GFP was decreased in cpi1-1 mutants, which was confirmed by fluorescence cross spectroscopy (FCS) analysis. Hence, these results demonstrate that sterol composition plays a critical role in the plant defense responses of Flot1. [ABSTRACT FROM AUTHOR]