This study, using species distribution modeling (involving a new approach that allows for uncertainty), predicts the distribution of climatically suitable areas prevailing during the mid-Holocene, the Last Glacial Maximum (LGM), and at present, and estimates the potential formation of new habitats in 2070 of the endangered and rare Tertiary relict tree Davidia involucrata Baill. The results regarding the mid-Holocene and the LGM demonstrate that south-central and southwestern China have been long-term stable refugia, and that the current distribution is limited to the prehistoric refugia. Given future distribution under six possible climate scenarios, only some parts of the current range of D. involucrata in the mid-high mountains of south-central and southwestern China would be maintained, while some shift west into higher mountains would occur. Our results show that the predicted suitable area offering high probability (0.5‒1) accounts for an average of only 29.2% among the models predicted for the future (2070), making D. involucrata highly vulnerable. We assess and propose priority protected areas in light of climate change. The information provided will also be relevant in planning conservation of other paleoendemic species having ecological traits and distribution ranges comparable to those of D. involucrata.

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Nutrient relocation, hydrological functions, and soil chemistry in plantations as compared to natural forests in central Yunnan, China Abstract The relocation of nutrients among dominant plant species, along with hydrological functions and soil chemistry in five plant communities, including Eucalyptus plantation, Pinus plantation, shrubland, semi-natural, and natural secondary forests were investigated in central Yunnan, China. The nutrient P, N, and K accumulation in above-ground biomass of Eucalyptus smithii (stems, barks, branches, and leaves) were the highest, followed by Pinus yunnanensis of both the Pinus plantation and the semi-natural forest. The nutrient retranslocation efficiency (NRE) of E. smithii was the highest for nutrient P, N, and K with values of 56, 66, and 67%, respectively, among the dominant plant species of the five plant communities, while the NRE of P. yunnanensis in Pinus plantation had the second highest value of NRE for nutrient N. The nutrient content (available P, N, and soil organic matter) in the upper two soil layers under Eucalyptus and Pinus plantations was correspondingly found to be lower than that of the other forests. Moreover, under the Eucalyptus and Pinus plantations, surface runoff, soil erosion, and nutrient loss were more serious, and the water storage of litterfall and canopy interception were significantly lower than that in the other plant communities. Accordingly, we suggest that single-species plantations cannot present the same ecological benefits as natural forests, because of their simple, uniform structures, and the characteristics of the dominant plant species.

The subtropical evergreen broad‐leaved forests of Yunnan and Taiwan were compared along environmental and successional gradients with the aim of identifying important taxon and species diversity as well as the drivers of mountain biodiversity patterns. A detrended correspondence analysis of an exhaustive set of data collected from 105 and 223 plots for Yunnan and Taiwan, respectively, was applied to classify natural mature forest types. Additional data from 72 and 68 plots for Yunnan and Taiwan, respectively, were used for analyses of secondary succession. The floristic richness and diversity index were calculated for each type of forest. In Yunnan, the monsoon forests in mesic‐humid sites had more taxa and tended to show higher species diversity than the other two forest types. In Taiwan, species diversity values were significantly higher in the Machilus–Castanopsis zone in the middle altitudes (500–1500 m) than for the other three forest zones. For both Yunnan and Taiwan, the forests at the middle successional stage showed significantly higher species diversity than those at the early successional stage. Differences in diversity between the middle and late stages were not significant. These findings highlight the high species diversity of the natural mature evergreen broad‐leaved forests of both Yunnan and Taiwan. In the secondary forests, as succession proceeds, species diversity comes to resemble that of the natural mature forests. In both ecosystems, the drivers of species diversity patterns are moisture, altitude, and succession/disturbance.