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Tropical forest phenology directly affects regional carbon cycles, but the relation between species‐specific and whole‐canopy phenology remains largely uncharacterized. We present a unique analysis of historical tropical tree phenology collected in the central Congo Basin, before large‐scale impacts of human‐induced climate change. Ground‐based long‐term (1937–1956) phenological observations of 140 tropical tree species are recovered, species‐specific phenological patterns analyzed and related to historical meteorological records, and scaled to characterize stand‐level canopy dynamics. High phenological variability within and across species and in climate–phenology relationships is observed. The onset of leaf phenophases in deciduous species was triggered by drought and light availability for a subset of species and showed a species‐specific decoupling in time along a bi‐modal seasonality. The majority of the species remain evergreen, although central African forests experience relatively low rainfall. Annually a maximum of 1.5% of the canopy is in leaf senescence or leaf turnover, with overall phenological variability dominated by a few deciduous species, while substantial variability is attributed to asynchronous events of large and/or abundant trees. Our results underscore the importance of accounting for constituent signals in canopy‐wide scaling and the interpretation of remotely sensed phenology signals. [ABSTRACT FROM AUTHOR]

A significant fraction of higher plants in China are threatened due to dramatic landscape transformation and increasing climate change. However, the conservation effectiveness of threatened higher plants (THPs) and their response to climate change are still underexplored to date. Based on the latest list of THPs in China, we obtained 102 593 occurrence records with latitude and longitude for 3858 THPs. By integrating the distribution patterns of three biodiversity indexes (i.e., species richness, species complementarity, and weighted endemism) and 10 plant categories, we identified hotspots for THPs and calculated the conservation effectiveness of nature reserves. We then selected 1959 THPs to project the shift of species richness and range sizes under climate change (representative concentration pathway [RCP] 2.6 and RCP 8.5). In total, 16 hotspot areas covering 7.38% of Chinese land area and containing 91.73% of THPs were identified. Current nature reserves protected 35.05% of hotspots, 73.07% of all THPs, and 56.64% of narrow‐ranged species. By the 2070s, the species richness of THPs were predicted to decrease in Southeast and Central China, and 42.42% (RCP 2.6) and 51.40% (RCP 8.5) of the 1959 THPs would confront habitat contraction. Future conservation efforts should focus on the conservation gaps and carry out targeted conservation for THPs with narrow distribution range. In order to cope with climate change, the hotspots with relatively low species loss can serve as important areas to contain current species diversity and the areas with high species gain offer opportunities for ex‐situ conservation of THPs. [ABSTRACT FROM AUTHOR]

Conventional wisdom states that genetic variation reduces disease levels in plant populations. Nevertheless, crop species have been subject to a gradual loss of genetic variation through selection for specific traits during breeding, thereby increasing their vulnerability to biotic stresses such as pathogens. We explored how genetic variation in Arabica coffee sites in southwestern Ethiopia was related to the incidence of four major fungal diseases. Sixty sites were selected along a gradient of management intensity, ranging from nearly wild to intensively managed coffee stands. We used genotyping‐by‐sequencing of pooled leaf samples (pool‐GBS) derived from 16 individual coffee shrubs in each of the 60 sites to assess the variation in genetic composition (multivariate: reference allele frequency) and genetic diversity (univariate: mean expected heterozygosity) between sites. We found that genetic composition had a clear spatial pattern and that genetic diversity was higher in less managed sites. The incidence of the four fungal diseases was related to the genetic composition of the coffee stands, but in a specific way for each disease. In contrast, genetic diversity was only related to the within‐site variation of coffee berry disease, but not to the mean incidence of any of the four diseases across sites. Given that fungal diseases are major challenges of Arabica coffee in its native range, our findings that genetic composition of coffee sites impacted the major fungal diseases may serve as baseline information to study the molecular basis of disease resistance in coffee. Overall, our study illustrates the need to consider both host genetic composition and genetic diversity when investigating the genetic basis for variation in disease levels. [ABSTRACT FROM AUTHOR]