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In order to understand the difference in microbial diversity between wild and cultivated Anemone altaica rhizosphere soils, Illumina MiSeq high-throughput sequencing technology was used to study the microbial composition and diversity in rhizosphere soils between wild and cultivated A. altaica. The results were as follows: (1) Alpha diversity analysis showed that the diversity of fungi in the rhizosphere soil of wild A. altaica was significantly higher than that of cultivated A. altaica (P0.05). The non-metric multidimensional scaling (NMDS) analysis revealed that the fungal community structures of wild and cultivated A. altaica rhizosphere soils had more significant differences. (2) A total of 9 566 operational taxonomic units (OTUs) of bacteria belonged to 39 phyla, 127 classes, 315 orders, 500 families and 886 genera, and 2 670 OTUs of fungi belonged to 15 phyla, 57 classes, 138 orders, 293 families and 597 genera. The bacterial phylum Proteobacteria, Acidobacteria, Actinobacteria and the fungal phylum Basidiomycota, Ascomycota, Mortierellomycota were the dominant phyla in the rhizosphere soil between wild and cultivated plants, but their relative abundance was different under different growth modes. At genus level, Candidatus_Udaeobacter, norank_f_Xanthobacteraceae and Rokubacteriales were the dominant rhizosphere soil bacteria of wild Anemone altaica. However, Candidatus_Udaeobacter, Vicinamibacter and Rokubacteriales were the dominant rhizosphere soil bacteria of cultivated Anemone altaica. The dominant rhizosphere fungi of wild A. altaica were Mortierella, Sebacina and Russula, while the dominant rhizosphere fungi of cultivated Anemone altaica were Sebacina, Mortierella and unclassified_f_Hyaloscyphaceae. (3) The redundancy analysis (RDA) showed that soil organic matter was the main factor affecting soil bacterial community (P < 0.05), and soil pH, alkali-hydrolyzable nitrogen and available phosphorus were the main factors affecting fungi communities (P < 0.05), while bacterial community structure were not significantly correlated with soil pH, alkali-hydrolyzable nitrogen and available phosphorus (P > 0.05). In summary, this study reveales significant differences in the composition and diversity of rhizosphere microbial communities between wild and cultivated A. altaica, which may be closely related to the physicochemical properties of soils under different growing conditions. The results of this study have certain significance for scientific planting and soil improvement of A. altaica.

Abstract Global warming accelerates water cycle, causing more droughts globally that challenge monitoring and forecasting. The Standardized Precipitation Evapotranspiration Index (SPEI) is used to assess drought characteristics and response time of natural and economic systems at various timescales. However, existing SPEI datasets have coarse spatial or temporal resolution or limited spatial extent, restricting their ability to accurately identify the start or end dates or the extent of drought at the global scale. To narrow these gaps, we developed a global daily SPEI dataset (SPEI-GD), with a 0.25° spatial resolution from 1982 to 2021 at multiple timescales (5, 30, 90, 180 and 360 days), based on the precipitation from European Center for Medium Weather Forecasting Reanalysis V5 (ERA5) dataset and the potential evapotranspiration from Singer’s dataset. Compared to widely used SPEIbase dataset, the SPEI-GD can improve the spatial-temporal resolution and the accuracy of SPEI in areas where meteorological sites are lacking. The SPEI-GD significantly correlates with site-based SPEI and soil moisture. Our dataset solidly supports sub-seasonal and daily-scale global and regional drought research.

Grassland, the most widespread vegetation type in China, has been greening recently.However, the extent to which the greenness has been translated into productivity and the underlying mechanism of the decoupled grassland greenness and productivity remains unclear. In this study, we detected the trend of normalized difference vegetation index (NDVI) and gross primary productivity (GPP) of grassland in China from 2000 to 2019 and analyzed the driving mechanism of the inconsistency between them. It was found that the relative increase rate of productivity (27.27%, p

Abstract The mechanisms causing European heatwaves in recent years, particularly their differences among several heatwaves, are poorly understood. Here atmospheric circulation anomalies and soil moisture‐temperature coupling during the summer 2018 heatwave are comprehensively examined and compared with the 2003 and 2010 heatwaves using ERA5 reanalysis, model simulations, and eddy covariance flux measurements. We show that the 2018 heatwave successively affected northern and central Europe, and the peak temperature in Finland and northwest Russia broke historical records of the past 40 years. Although three heatwaves were all initially triggered by atmospheric circulation anomalies, the strong moisture‐temperature coupling were found to further strengthen the 2003 and 2010 heatwaves. This coupling was also strong in central Europe during 2018 heatwave, but was weak in the northern European center of the heatwaves. The high temperature in 2018 was mainly due to increases in the amount of net surface radiation caused by the clear skies associated with reduced precipitation. Furthermore, we also find that land cover plays a critical role in determining the occurrence and strength of soil moisture‐temperature coupling. Cropland/grassland depletes soil moisture more readily than forests, thereby triggering a more rapid release of sensible fluxes as observed during 2018 heatwave.