Key Laboratory of Ecohydrology of Inland River Basin, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, 730000, China; University of Chinese Academy of Sciences, Beijing, 100049, China.
Key Laboratory of Ecohydrology of Inland River Basin, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, 730000, China.
J Environ Manage. 2023 Jan 15;326(Pt A):116708. doi: 10.1016/j.jenvman.2022.116708. Epub 2022 Nov 7.
The increased frequency and intensity of droughts have seriously affected the stability of plantation ecosystems in the Chinese Loess Plateau. Caragana korshinskii Kom. was the dominant afforested shrub species in this region. Evaluating the radial growth of C. korshinskii and its response to drought can provide valuable information for sustainable management of plantations in the context of climate change. In this study, based on 237 shrub C. korshinskii annual ring samples from nine sites in different climate regions, we investigated the response of C. korshinskii radial growth to climate (temperature, precipitation, and monthly resolved standardized precipitation evapotranspiration index (SPEI_01)), and evaluated the differences between them using calculated indices of drought resistance, recovery, and resilience. The results demonstrate that the radial growth of C. korshinskii was mainly limited by drought stress in the previous September in arid regions and in March and June in semi-arid regions, whereas C. korshinskii in semi-humid regions was less influenced by drought stress. Recovery after drought decreased with increasing resistance, and resilience increased significantly with increasing resistance and recovery. Differences in precipitation were found to be the main factor generating variations in shrub resilience; with an increase in precipitation, the recovery and resilience after drought gradually increased. For plantation management, this study suggests that efficient utilization of precipitation resources and site-specific afforestation in different climate and site conditions may help to enhance resilience and improve the ecological service function of plantation forests in the Loess Plateau.
干旱的频率和强度增加已经严重影响了中国黄土高原人工林生态系统的稳定性。柠条锦鸡儿（Caragana korshinskii Kom.）是该地区主要的造林灌木树种。评估柠条锦鸡儿的径向生长及其对干旱的响应，可以为气候变化背景下的人工林可持续管理提供有价值的信息。在这项研究中，基于来自九个不同气候区的 237 个柠条锦鸡儿灌木年轮样本，我们研究了柠条锦鸡儿径向生长对气候（温度、降水和月分辨率标准化降水蒸散指数（SPEI_01））的响应，并使用计算出的抗旱性、恢复力和弹性指数评估了它们之间的差异。结果表明，柠条锦鸡儿的径向生长主要在前一年的 9 月（干旱区）和 3 月和 6 月（半干旱区）受到干旱胁迫的限制，而半湿润区的柠条锦鸡儿受干旱胁迫的影响较小。干旱后的恢复力随着抗旱性的增加而降低，而弹性则随着抗旱性和恢复力的增加而显著增加。降水的差异被发现是导致灌木弹性变化的主要因素；随着降水的增加，干旱后的恢复力和弹性逐渐增加。对于人工林管理，本研究表明，在不同气候和立地条件下有效利用降水资源和进行特定地点的造林，可能有助于提高人工林的弹性，并改善黄土高原人工林的生态服务功能。
