Seasonal response of light use efficiency of <i>Artemisia ordosica</i> to leaf traits in Mu Us sandy land

PDF HTML阅读 XML下载 导出引用 引用提醒 毛乌素沙地油蒿叶性状对光能利用效率动态的影响 DOI: 10.5846/stxb202203240732 作者: 作者单位: 作者简介: 通讯作者: 中图分类号: 基金项目: 国家自然科学基金（32101588，32071842，31901366，32071843） Seasonal response of light use efficiency Artemisia ordosica to leaf traits in Mu Us sandy land Author: Affiliation: Fund Project: Fundamental Research Funds for the National Natural Science Foundation China (NSFC, grant numbers 32101588, 32071842, 31901366 and 32071843) 摘要 | 图/表 访问统计 参考文献 相似文献 引证文献 资源附件 文章评论 摘要:目前对于荒漠灌木光能利用效率（LUE）的季节变异及其调控因素，尤其是其生物调控因素的认识非常有限，导致了荒漠生态系统生产力模型的不确定性。拟验证假设：长期干旱环境下，典型荒漠灌木油蒿光能利用效率日均值（LUEday）的动态变化与叶片性状的季节性调整有关。试验采用Li-6400便携式光合仪定期测量了油蒿生长季叶片LUEday的季节动态及相关叶性状指标，探究叶性状对LUEday的影响。结果表明：LUEday的季节波动范围为0.003-0.017 mol/mol，整体变异系数（CV）为38.75%。完全展叶期LUEday均值相比生长季平均值降低17.37%，相比展叶期和落叶期时降低30%；8个叶性状的季节变异幅度差异较大，其中总叶绿素含量（Chl）、类胡萝卜素含量（Car）和叶氮含量（LNC）均表现出较大的季节变异性（CV ≥ 20%），叶碳含量（LCC）和叶片相对含水量（LRWC）的变异程度最低（CV<7%）。LRWC与所有叶片化学性状（Chl、Chl a/b、Car、LNC和LCC）均存在显著相关，表明其变化与叶片的养分吸收、光合色素合成以及碳同化的运输过程密切相关；油蒿LUEday的相对变化与LRWC、Chl a/b和LNC显著正相关，而LRWC和LNC的季节动态受空气温度（Ta）和土壤含水量（VWC）的共同调节，Chl a/b的季节波动主要由浅层土壤含水量（10 cm VWC）控制。以上研究结果强调，在未来预计极端的气候事件（如极端干旱和持续热浪事件）发生更频繁的旱地场景中，时间尺度植物叶性状对于土壤干旱和高温的适应性调整应当被充分考虑到旱地生态系统的通量建模方案中。该结果将为构建叶片尺度的光合生理模型与厘清LUE的生物调控机制提供理论依据。 Abstract:The understanding on seasonal variation (LUE) desert shrubs its regulatory factors, especially biological ones, is very limited, leading uncertainty productivity model ecosystems. We hypothesize that change daily mean LUE (LUEday) related adjustment a long-term drought environment. To test this hypothesis, LUEday key functional were measured with portable photosynthetic system their relationships analyzed during growing season. The fluctuation range was 0.003-0.017 mol/mol, coefficient (CV) 38.75%. at expanded period 17.37% lower than whole season, about 30% expanding defoliation period. Eight showed different degrees, CV values total chlorophyll content (Chl), Carotenoid (Car) nitrogen (LNC) generally higher over 20%, carbon (LCC) relative water (LRWC) less 7%. LRWC significantly correlated all biochemical (i.e., Chl, Chl a/b, Car, LNC LCC), indicating changes tightly transport process nutrient absorption, pigment synthesis assimilation leaves. positively LRWC, a/b LNC. variations mainly regulated by air temperature (Ta) soil volume (VWC). Moreover, controlled 10 VWC. Considering many studies predict more extreme climate events (e.g., continuous heat wave events) will occur dryland future, these findings emphasized plant high should be fully considered flux modeling scheme ecosystem. Our results help construct scale understand regulation mechanism xerophyte species.