College of Life and Environmental Sciences, Central South University of Forestry and Technology, Changsha, Hunan, China.
Huitong National Station for Scientific Observation and Research of Chinese Fir Plantation Ecosystems in Hunan Province, Huitong, Hunan, China.
Glob Chang Biol. 2024 Nov;30(11):e17561. doi: 10.1111/gcb.17561.
Climate warming is projected to affect hydrological cycle in forest ecosystems and makes the forest-water relationship more controversial. Currently, planted forests are gaining more public attention due to their role in carbon sequestration and wood production relative to natural forests. However, little is known about how the global patterns and drivers of water yield and water-use efficiency (WUE) differ between planted and natural forests. Here, we conduct a global analysis to compare water yield and WUE in planted and natural forests using 946 observations from 112 published studies. The results showed that global average water yield coefficient was 0.29 for planted forests and 0.34 for natural forests. Planted forests exhibited lower water yield coefficient (p < 0.05) in three climatic regions (arid, dry subhumid, and humid regions), but higher (p < 0.01) WUE only in arid region, compared with natural forests. Both water yield coefficient and WUE in planted forests were significantly lower (p < 0.05) than that in natural forests for stand characteristic groups (stand density, average tree height, leaf area index [LAI], and basal area). Additionally, stand density within the ranging between 1000 to 2000 stem ha can maximize the water yield and WUE in planted and natural forests. Water yield coefficient in planted forests was primarily controlled by the factors related to tree growth (i.e., tree height, DBH), while that of natural forest mainly affected by stand structure (i.e., LAI, stand density, DBH). WUE in planted forest was more sensitive to climate than in natural forests. This work highlights the critical role of natural forests in water supply and the importance of tree species selection and stand management (e.g., stand density adjustment) in plantations in future forest restoration policies and climate change mitigation.
气候变暖预计会影响森林生态系统的水文循环，使森林-水关系变得更加复杂。目前，人工林由于其在碳固存和木材生产方面相对于天然林的作用而受到更多关注。然而，人们对人工林和天然林的产水量和水分利用效率（WUE）的全球格局和驱动因素的差异知之甚少。在这里，我们利用 112 项已发表研究中的 946 个观测值，进行了一项全球分析，以比较人工林和天然林的产水量和 WUE。结果表明，全球平均产水系数为人工林 0.29，天然林 0.34。与天然林相比，人工林在干旱、干燥的半湿润和湿润地区的产水系数（p < 0.05）较低，但在干旱地区的水分利用效率（p < 0.01）较高。与天然林相比，人工林的产水系数（p < 0.05）和水分利用效率（p < 0.05）在林分特征组（林分密度、平均树高、叶面积指数[LAI]和基面积）中均较低。此外，在 1000 至 2000 株/公顷的范围内，林分密度可以使人工林和天然林的产水量和水分利用效率最大化。人工林的产水系数主要受与树木生长相关的因素（即树高、胸径）控制，而天然林的产水系数主要受林分结构（即 LAI、林分密度、胸径）影响。人工林的水分利用效率对气候的变化比天然林更敏感。这项工作强调了天然林在供水方面的关键作用，以及在未来森林恢复政策和减缓气候变化中树种选择和林分管理（如林分密度调整）的重要性。
