Background Trace elements are essential for the growth and survival of plants, and their concentrations and distributions in plants are effective reflections of ecological adaptation strategies. However, this aspect has seldom been addressed. Method Changes in the leaf and branch trace elements of Pinus massoniana Lamb, induced by seasonal dynamics and in response to a 3-yr 100% rainfall exclusion, were evaluated. Results The results showed that the concentrations of Fe, Cu, Zn, Cd, Ni and Cr in leaves of P. massoniana in the control group had high seasonal resolution. There were three groups according to their patterns over the growing season: (1) nutrient elements (Cu, Zn, Ni and Cd), which continuously decreased in concentration during the growing season, with the highest concentration in spring and the lowest in autumn; (2) accumulating element (Cr), which increased in concentration from spring to autumn; and (3) indifferent element (Fe), which increased in concentration from spring to summer and decreased in concentration from summer to autumn. The concentrations of trace elements in leaves and branches showed no significant differences with mild drought stress, except for Fe and Cr in leaves and Cr in branches, which significantly increased (p < 0.05) under the result of self-selection under mild drought stress. Therefore, the resultant seasonal and drought effects on trace element cycling in P. massoniana could provide theoretical support to respond to future climate change.

中文翻译：

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叶枝微量元素的季节变化及 3 年 100% 降雨排除对马尾松羔羊的影响

背景微量元素对植物的生长和生存至关重要，它们在植物中的浓度和分布是生态适应策略的有效体现。然而，这方面很少得到解决。方法 评估了由季节动态和 3 年 100% 降雨排除引起的马尾松叶和枝条微量元素的变化。结果结果表明，对照组马尾松叶片中Fe、Cu、Zn、Cd、Ni和Cr的浓度具有较高的季节分辨率。生长期按规律分为三组：（1）营养元素（Cu、Zn、Ni、Cd），生长期浓度持续下降，春季最高，秋季最低；（2）富集元素（Cr），从春季到秋季浓度增加；(3)中性元素(Fe)，其浓度从春季到夏季增加，从夏季到秋季减少。叶、枝中微量元素的含量与轻度干旱胁迫无显着差异，但在轻度干旱胁迫下，叶、枝中微量元素的浓度在自选择结果下显着增加（p < 0.05），而枝条中的Cr则显着增加（p < 0.05）。因此，由此产生的季节和干旱对马尾松微量元素循环的影响可为应对未来气候变化提供理论支持。从春季到夏季浓度增加，从夏季到秋季浓度降低。叶、枝中微量元素的浓度与轻度干旱胁迫无显着差异，但轻度干旱胁迫下叶片中的Fe、Cr和枝条中的Cr在自选择结果下显着增加（p < 0.05）。因此，由此产生的季节和干旱对马尾松微量元素循环的影响可为应对未来气候变化提供理论支持。从春季到夏季浓度增加，从夏季到秋季浓度降低。叶、枝中微量元素的浓度与轻度干旱胁迫无显着差异，但轻度干旱胁迫下叶片中的Fe、Cr和枝条中的Cr在自选择结果下显着增加（p < 0.05）。因此，由此产生的季节和干旱对马尾松微量元素循环的影响可为应对未来气候变化提供理论支持。