Background Vegetation phenology research has largely focused on temperate deciduous forests, thus limiting our understanding of the response of evergreen vegetation to climate change in tropical and subtropical regions. Results Using satellite solar-induced chlorophyll fluorescence (SIF) and MODIS enhanced vegetation index (EVI) data, we applied two methods to evaluate temporal and spatial patterns of the end of the growing season (EGS) in subtropical vegetation in China, and analyze the dependence of EGS on preseason maximum and minimum temperatures as well as cumulative precipitation. Our results indicated that the averaged EGS derived from the SIF and EVI based on the two methods (dynamic threshold method and derivative method) was later than that derived from gross primary productivity (GPP) based on the eddy covariance technique, and the time-lag for EGSsif and EGSevi was approximately 2 weeks and 4 weeks, respectively. We found that EGS was positively correlated with preseason minimum temperature and cumulative precipitation (accounting for more than 73% and 62% of the study areas, respectively), but negatively correlated with preseason maximum temperature (accounting for more than 59% of the study areas). In addition, EGS was more sensitive to the changes in the preseason minimum temperature than to other climatic factors, and an increase in the preseason minimum temperature significantly delayed the EGS in evergreen forests, shrub and grassland. Conclusions Our results indicated that the SIF outperformed traditional vegetation indices in capturing the autumn photosynthetic phenology of evergreen forest in the subtropical region of China. We found that minimum temperature plays a significant role in determining autumn photosynthetic phenology in the study region. These findings contribute to improving our understanding of the response of the EGS to climate change in subtropical vegetation of China, and provide a new perspective for accurately evaluating the role played by evergreen vegetation in the regional carbon budget.

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Introduction Fungal plant pathogens are an emerging threat to economically important crop production worldwide and a significant risk to global food security. However, we have limited knowledge of how agricultural management practices drive the emergence and spread of pathogens within crop microbiomes and the underlying ecological mechanisms. Materials and Methods We characterized the profiles of potential fungal plant pathogens, as well as bacterial and protistan communities, in sorghum phyllosphere, root endosphere, and rhizosphere and bulk soils collected from a long‐term experiment with multiple inorganic and organic fertilization regimes. Results We found contrasting patterns of fungal plant pathogens across the four sorghum–soil compartments and that organic fertilization regime significantly reduced the diversity and proportions of fungal plant pathogens in rhizosphere and bulk soils. We further found that the changes in fungal plant pathogens were driven more by resident bacterial and protistan communities than by soil physicochemical parameters. There was a significantly negative relationship between the diversity of fungal plant pathogens in the rhizosphere and bulk soils with sorghum yield and protein contents. Structural equation modeling revealed that long‐term organic fertilization regimes contributed to the suppression of fungal plant pathogens mainly through modulating the resident bacterial and protistan communities. Conclusion These findings advance our understanding of the responses of fungal plant pathogens in crop microbiomes to fertilization regimes, with implications for more targeted strategies to manage the impacts of fungal pathogens on plant health and economic losses.

Urbanization can induce environmental changes such as the urban heat island effect, which in turn influence the terrestrial ecosystem. However, the effect of urbanization on the phenology of subtropical vegetation remains relatively unexplored. This study analyzed the changing trend of vegetation photosynthetic phenology in Dongting Lake basin, China, and its response to urbanization using nighttime light and chlorophyll fluorescence datasets. Our results indicated the start of the growing season (SOS) of vegetation in the study area was significantly advanced by 0.70 days per year, whereas the end of the growing season (EOS) was delayed by 0.24 days per year during 2000–2017. We found that urbanization promoted the SOS advance and EOS delay. With increasing urbanization intensity, the sensitivity of SOS to urbanization firstly increased then decreased, while the sensitivity of EOS to urbanization decreased with urbanization intensity. The climate sensitivity of vegetation phenology varied with urbanization intensity; urbanization induced an earlier SOS by increasing preseason minimum temperatures and a later EOS by increasing preseason precipitation. These findings improve our understanding of the vegetation phenology response to urbanization in subtropical regions and highlight the need to integrate human activities into future vegetation phenology models.

AimsThis study investigated the spatial and temporal variation of spring and autumn photosynthetic phenology of vegetation in the Dongting Lake basin and revealed its response to climate change, and provides a useful reference for the establishment of model of subtropical vegetation phenology and the evaluation of carbon budget.Methods Using solar-induced chlorophyll fluorescence (SIF) data, we extracted spring photosynthetic phenology (the start date of photosynthesis) and autumn photosynthetic phenology (the end date of photosynthesis) of vegetation in Dongting Lake basin, and evaluated temporal and spatial patterns of vegetation spring and autumn photosynthetic phenology and its response to climate change.Important findings (1) From 2000 to 2018, the vegetation spring photosynthetic phenology was significantly advanced at the rate of 0.75 d•a -1 , the autumn photosynthetic phenology was delayed at the rate of 0.17 d•a -1 , and the vegetation growing season length was significantly prolonged at the rate of 0.90 d•a -1 . (2) The preseason maximum air temperature and minimum air temperature were the main factors affecting the advance of spring photosynthetic phenology. The autumn photosynthetic phenology of vegetation was positively correlated with preseason precipitation, minimum air temperature and radiation intensity, but negatively correlated with preseason