【摘要】 为揭示渭北黄土高原混交林和纯林径向生长对气候变化的响应及应对极端干旱能力的差异，以黄土高原典型丘陵区延安市安塞县油松、刺槐混交林和纯林为研究对象；依据帕默尔干旱指数(PDSI)选择2005-2009年和2019年两次极端干旱事件，使用156根树轮样芯，分别建立了4个林分的树轮宽度年表并量化了树木的抵抗力和恢复力。结果表明，在极端干旱事件发生年和气候适宜年，油松混交林年轮宽度均显著高于纯林，但刺槐纯林的年轮宽度显著高于刺槐混交林；气候响应方面，PDSI对油松纯林和混交林径向生长的促进作用强于刺槐；刺槐混交林对干旱的抵抗力显著高于刺槐纯林和油松林，四种林分的恢复力没有显著差异。本研究结果表明，混交营林模式显著提高了刺槐对干旱的适应能力，营造刺槐混交林将有助于提高黄土高原地区人工林对日益干旱环境的适应性。更多还原

【Abstract】 In order to reveal the response of radial growth of mixed forest and pure forest to climate change and the difference in adaption to extreme drought in the Loess Plateau, the mixed forest and pure forest of Pinus tabulaeformis and Robinia pseudoacacia in the typical hilly area of the Loess Plateau were studied. Based on the Palmer Drought Index(PDSI), two extreme drought events in 2005-2009 and 2019 were selected. Using 156 tree-ring cores, tree-ring width chronologies of four stands were established and the resistance and resilience of trees were quantified. The results showed that the annual ring width of P. tabulaeformis mixed forest was significantly higher than that of pure forest in the years of extreme drought events and suitable climate years. However, the annual ring width of Robinia pseudoacacia pure forest was significantly higher than that of Robinia pseudoacacia mixed forest. In terms of climate response, PDSI has a stronger effect on the radial growth of Pinus tabulaeformis pure forest and mixed forest than Robinia pseudoacacia. The resistance of Robinia pseudoacacia mixed forest to drought was significantly higher than that of Robinia pseudoacacia pure forest and Pinus tabulaeformis forest, and there was no significant difference in the resilience of the four forests. The results of this study showed that the mixed forest model significantly improved the adaptability of R. pseudoacacia to drought, and the construction of R. pseudoacacia mixed forest will help to improve the adaptability of plantations in the Loess Plateau to increasingly arid environments.更多还原