Resilience to drought represents an important focus for trees during climate change, with the aim of predicting the resistance and recovery of species worldwide. Previous studies mainly linked tree growth resilience to plant functional traits that are related to resource acquisition and investment. Here, we investigate a potential link between resilience and the amount of parenchyma tissue in wood, a multifunctional tissue that may provide various physiological benefits to drought‐related mechanisms. We compiled a global tree‐ring data set to evaluate the relationship between growth resistance, resilience or recovery from drought and xylem parenchyma tissue fractions of 50 angiosperms, which was complemented with a local study of nine species from Mt. Tiantong in China. We also assessed the influence of climate and phylogeny on these relationships. We found that growth recovery after drought was positively related to the fractions of total parenchyma locally and globally. This association remained statistically significant when accounting for the effects of climate and phylogeny. No other associations between parenchyma fractions and growth resilience metrics were statistically significant. Our results suggest that drought recovery of angiosperm trees is affected by the amount of parenchyma. Incorporating xylem parenchyma fraction with other traits, such as hydraulic traits, could therefore enhance our comprehension of how various angiosperm tree species will respond to future droughts. Further studies should focus on unravelling the physiological roles of xylem parenchyma fraction. Read the free Plain Language Summary for this article on the Journal blog.

Parenchyma in the secondary xylem comprises the main tissue for the storage of non-structural carbohydrates (NSC) in woody plants. Across species, the amount of parenchyma depends on the general environment of the distribution area and determines to a large extent the NSC storage. However, little information is available on the relationship between parenchyma fractions, NSC storage, and the environmental influences within individual species. This information is crucial to assessing the adaptive capacities of tree populations in the context of increasing the frequency and severity of stress-inducing events. In this study, parenchyma fractions and NSC concentrations of the secondary xylem in trunks of a subtropical evergreen oak (Quercus ciliaris C.C.Huang & Y.T.Chang) were quantified along an elevational gradient from 700 m to 1200 m a.s.l. in eastern China. Air temperatures within the distribution area correlated with altitude were recorded. The results showed that the total parenchyma fractions did not covary with the colder temperatures. However, axial parenchyma fractions were lower with a colder climate, while the fractions of multiseriate rays and total ray parenchyma were higher. Higher concentrations of starch and NSC were significantly associated with larger axial parenchyma fractions. The sugar concentration displayed no significant relationship with parenchyma fractions. These findings suggest that the total parenchyma fractions in secondary xylem do not increase in response to a colder climate, while colder temperatures drive changes in the composition of parenchyma for Q. ciliaris.

Forest parks provide important recreational and tourism benefits to residents, so it is essential to know what residents' perceptions are regarding the recreational value of forest parks for participatory forest planning and management. This study investigated forest park recreational value in the physical, psychological, and social dimensions in Shanghai according to questionnaires completed by 658 respondents, and examined the relationships between recreational value and residents' social variables by multiple correspondence analysis (MCA). The results show the following: 1) The recreational value of forest parks is perceived as most important in the psychological dimension, while in the social dimension it is appreciated the least. 2) In terms of the differences in forest park recreational value in suburbs and rural areas, the social value in rural areas had significantly higher scores than in the suburbs, and the psychological value in suburbs is much higher than that in the rural areas. 3) Regarding the social variables which characterize residents in suburbs and rural areas, females and younger groups tended to assign higher scores to recreational value than males and older groups. Moreover, citizens with low education or low income also assigned higher scores to recreational value compared to more educated or higher-income residents. The results of this study reveal the recreational value characteristics of Shanghai forest parks in the three dimensions, which can provide a scientific basis for the sustainable development of urban forest resources and contribute to reasonable planning and management.