![]() We conducted a meta‐analysis to investigate the pantropical importance of total soil P in mediating forest litterfall resistance and resilience to 22 tropical cyclones. ![]() Single‐site studies in Australia and Hawaii suggest that litterfall on low‐phosphorus (P) soils is more resistant and less resilient to cyclones. While tropical cyclone regimes are shifting with climate change, the mechanisms underpinning the resistance (ability to withstand disturbance‐induced change) and resilience (capacity to return to pre‐disturbance reference) of tropical forest litterfall to cyclones remain largely unexplored pantropically. The study is expected to facilitate the precise recognition and forestry management on Mount Tai. Sensitive spectral indices introduced were shown to significantly improve the recognition accuracy for tree species over a single sensitive band. pseudoacacia, were higher overall than that of the MLE. On 12 May, the recognition accuracies of SVM based on sensitive spectral indices of up to 93.59% for O. Moreover, the overall recognition accuracy of deciduous tree species on 12 May reached 89.25%, which was significantly higher than the other two phases. Band 4 is the most sensitive band in all the three phases for the tree species recognition. ![]() pseudoacacia were found in the spring (12 May), which was identified as the optimum phenological phase. pseudoacacia Compared to other phenological periods, the most significant spectral differences between O. The results showed the average spectral reflection intensity of O. ![]() acutissima ) and Robinia pseudoacacia (R. Support vector machine (SVM) and maximum likelihood model (MLE) are constructed to explore the optimum phase of recognizing on Quercus acutissima (O. Multispectral images of Ziyuan–1 02C (ZY–1 02C) and Ziyuan–3 (ZY–3) at three phenological phases of spring, autumn and winter (12 May, 29 September and 7 December, recorded as T5–12, T9–29 and T12–7) are selected to optimize sensitive spectral indices. However, the complex phenological cycle poses a challenge to remote–sensing recognition of deciduous tree species in mountainous areas, and the selection of temporal phase is particularly important to improve recognition accuracy. Tree species recognition is important for remote–sensing mapping and dynamic monitoring of forest resource. ![]() These results will be valuable to understanding functional strategies for plants under varying wind loads, especially synchronous variations in leaf traits along a wind gradient. However, the intercept of correlations was affected by wind, and leaf N and P use efficiency decreased under the wind load, which suggests that the Quercus species changes from "fast investment-return" in the control to "slow investment-return" under windy conditions. Leaf N concentrations showed a positive correlation to SLA, leaf N and P concentrations showed positive correlations to LDI under each wind treatment, and the slope of correlations was not affected by wind, which indicates synchronous variations between leaf stoichiometry and leaf morphology under wind. Leaf N:P was relatively stable under wind for all species, which supports stoichiometric homeostasis. Leaf N and P concentrations increased significantly under these conditions for Quercus acutissima, Quercus rubra, Quercus texana, and Quercus palustris-which have elliptic leaves-due to their higher N, P requirements and a resultant leaf biomass decrease, which is a tolerance strategy for Quercus species under a wind load. We determined the leaf N and P concentrations and leaf morphology-including specific leaf area (SLA) and leaf dissection index (LDI)-for eight Quercus species under a simulated wind load for seven months. However, it is not clear how leaf N, P stoichiometry and its relationship to leaf morphology changes with wind load. Leaf nitrogen (N) and phosphorus (P) stoichiometry correlates closely to leaf morphology, which is strongly impacted by wind at multiple scales. ![]()
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