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The distribution of forest vegetation and forest carbon sequestration potential are significantly influenced by climate change. In this study, a map of the current distribution of vegetation in Yunnan Province was compiled based on data from remote sensing imagery from the Advanced Land Observing Satellite (ALOS) from 2008 to 2011. A classification and regression tree (CART) model was used to predict the potential distribution of the main forest vegetation types in Yunnan Province and estimate the changes in carbon storage and carbon sequestration potential (CSP) in response to increasing temperature. The results show that the current total forest area in Yunnan Province is 1.86 × 107 ha and that forest covers 48.63% of the area. As the temperature increases, the area of forest distribution first increases and then decreases, and it decreases by 11% when the temperature increases from 1.5 to 2 °C. The mean carbon density of the seven types of forest vegetation in Yunnan Province is 84.69 Mg/ha. The total carbon storage of the current forest vegetation in Yunnan Province is 871.14 TgC, and the CSP is 1100.61 TgC. The largest CSP (1114.82 TgC) occurs when the temperature increases by 0.5 °C. Incremental warming of 2 °C will sharply decrease the forest CSP, especially in those regions with mature coniferous forest vegetation. Semi-humid evergreen broad-leaved forests were highly sensitive to temperature changes, and the CSP of these forests will decrease with increasing temperature. Warm-hot coniferous forests have the greatest CSP in all simulation scenarios except the scenario of a 2 °C temperature increase. These results indicate that temperature increases can influence the CSP in Yunnan Province, and the largest impact emerged in the 2 °C increase scenario. [ABSTRACT FROM AUTHOR]

The survival strategy and ecophysiological process of rubber trees (Hevea brasiliensis), in which water-use efficiency (WUE) represents a vital indicator linking the carbon and water cycles, are mediated by phenology and can be severely affected by a low fruit-set rate and cold stress. However, the phenology-related WUE and its temporal variation as well as its responses to site heterogeneity in rubber plantations remain poorly understood. In this study, we used a four-year (2013–2016) continuous dataset of biometric survey, sap flow and phenology of rubber trees to examine the WUE in response to phenological changes and cold stress. The planting density and stand age, factors exhibiting a considerable difference and contributing to site heterogeneity, were explored to reveal their effects on the WUE of rubber plantations in Yunnan Province of Southwest China. Unexpectedly, the response of the WUE to phenological changes was characterized by the peak value (2.73±0.59 g C kg−1 H 2 O) that occurred simultaneously with the fruiting period (P f), and the WUE values during the P f were significantly higher than that of other phenological periods (P <0.01), indicating that the survival strategy adopted by the rubber trees to cope with the low fruit-set rate as well as cold stress during the defoliation period (P d) and adapt to the local climate might be very effective. However, this effectiveness might be reduced to some extent, since the WUE was significantly affected by the planting density (df =2, F -value=11.51) and stand age (df =3, F -value=22.84) indicated by one-way analysis of variance (P <0.01). These findings can provide a deeper understanding for the adaptation strategies to adverse climate and the cultivation and management of rubber plantations. [Display omitted] • The annual life cycle of rubber trees was divided into four phenological periods. • Water-use efficiency (WUE) revealed the survival strategy of rubber trees. • Maximum WUE values occurred simultaneously with the fruiting period (P f). • The planting density and stand age significantly affected the WUE. • Increases in the planting density tended to decrease the WUE of rubber trees. [ABSTRACT FROM AUTHOR]