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• Different species have the diverse responses to climate change. • Explored the growth-climate relationships of subtropical six tree species. • Most tree species are suffering from severe drought stress. • Broadleaved trees are generally better adapted to drought events than conifers. The young secondary forests in subtropical regions of China play an important role in the global carbon cycle and China's ecological and economic security. These values are closely related to tree radial growth (RW), primarily affected by climate changes, especially climate warming. Here, we measured the RW of six common tree species in subtropical China (Cunninghamia lanceolata , Pinus massoniana , Metasequoia glyptostroboides , Liquidambar formosana , Choerospondias axillaris , and Lithocarpus glaber) and quantified how each responded to climate warming. Temperature and moisture were the main climate factors limiting the growth of tree species in the study area. The growth of tree species other than L. formosana and P. massoniana was negatively correlated with temperature and positively correlated with relative humidity. Precipitation in the growing season was negatively correlated with the growth of L. formosana and M. glyptostroboides and positively affected the growth of the other tree species. The radial growth trends of trees growing in similar terrain and climate conditions were similar, but their degree of variation was different. Compared to broad-leaved tree species (L. formosana , C. axillaris , and L. glaber), coniferous tree species (C. lanceolata , P. massoniana , and M. glyptostroboides) were more climate-sensitive, particularly C. lanceolata. Climate warming can potentially extend the growing period and promote the radial growth of the study tree species, but more often leads to drought stress that inhibits radial growth. The long-term drought during 2004–2015 significantly reduced the radial growth of most species, especially conifers which are more vulnerable to drought than broad-leaved trees. Our results highlight that most tree species in the humid subtropical forest in South China are suffering from severe drought stress, which significantly affects forest carbon sequestration. It is probably a good warning for current plantation policy and species selection to better achieving the "Carbon Peaking & Carbon Neutrality" goals of the Chinese government. [ABSTRACT FROM AUTHOR]

• PAs' edges performed a weak but significant role in vegetation growth on the TP. • Over 40% of the areas showed the positive impact on vegetation growth. • A few samples showed a opposite effect on greenness, cover, and productivity. • Attention should be paid to these PAs' edge with a high fragmented landscape. Protected areas (PAs) are the cornerstones of global vegetation conservation efforts, but growing evidence showed the limited effectiveness of PAs in some regions. Recent attempts to quantify conservation efficiency were mainly focused on vegetation coverage, overlooking other vegetation characteristics, such as greenness and productivity. Here, using multiple indices of vegetation status from satellite observations and a windows search strategy, we measured the conservation efficiency of nature reserves (NRs, the primary category of PAs in China) edge on vegetation greenness, cover, and productivity on the Tibetan Plateau. The results showed that NRs' edges performed a weak, but significant role in vegetation growth. Over 40% of the areas showed a positive impact of NRs' edge on vegetation growth in different degrees. However, about 10% of the areas located on NRs' edge showed a noticeable opposite effect on greenness, cover, and productivity. Compared to some climatic and socio-economic factors (e.g., population density and air temperature), fragmented landscapes and landforms are more likely to inhibit conservation efficiency. The findings of this work can help better understand PAs' role in securing vegetation conservation and optimize the design of PAs for preventing vegetation losses. [ABSTRACT FROM AUTHOR]

Taking the northeast slope of Moxi vally and southwest slope of Kangding vally in Gongga Mountain of Southwest China as sampling sites, this paper investigated the leaf mass per unit area (LMA) and tissue non-structural carbohydrates content (NSC) of Abies fabri distributed at the positions from lower elevations to alpine treeline during the periods of dormancy and vigorous growth. The results indicated that A. fabri had higher LMA and NSC in warm-moist Moxi valley than in hot-dry Kangding valley. The LMA and NSC of treeline trees were all higher than those of the trees at lower elevations, which was more obvious during the period of vigorous growth. The overall altitudinal changing trends of LMA and NSC in Gongga Mountain of Southwest China did not support the hypothesis of 'carbon limitation could induce the formation of alpine treeline'.