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| 卡麦里山不同坡位花花柴光合日变化特征及其与环境因子关系 |
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罗玲吕1,2, 孙刚3, 王旭3, 谢立杰4, 彭黄叶1,2, 严彩玉1,2, 韩炜1,2
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1.新疆师范大学 地理科学与旅游学院，新疆 乌鲁木齐 830054;2.新疆干旱区湖泊环境与资源重点实验室，新疆 乌鲁木齐 830054;3.新疆林业科学院 园林绿化研究所，新疆 乌鲁木齐 830000;4.新疆生产建设兵团 第五师畜牧水产发展服务中心，新疆 双河 833408
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| 摘要: |
| 【 目的】研究荒漠植物花花柴（Karelinia caspia）光合特性在不同坡位的分异，探究驱动花花柴光合特 性分异的要素和机制，为干旱区植被恢复提供参考。【 方法】以新疆卡拉麦里山丘陵地带典型沟谷区坡底与坡顶的花 花柴个体为研究对象，利用Ll-6400XT便携式光合分析仪，于晴朗天气下连续3 d监测同一沟谷两个坡位6株成龄花花柴9个时段的光合指标（净光合速率（Pn）、蒸腾速率（Tr）、胞间CO2浓度（Ci）、气孔导度（Gs）、叶面温度（Tl）、叶面蒸汽 压亏缺（VPD））和环境因子（光合有效辐射（PAR）、气温（Ta）、相对湿度（RH）、大气CO2浓度（Ca）），用铝盒和环刀法同步测定土壤含水量（SMC）、土壤体积质量（Pb），计算气孔限制值（Ls）、水分利用效率（WUE）和光能利用效率（LUE）， 并对相关指标进行方差分析、相关分析、回归分析与通径分析，探究以PAR、Ta、Ca、RH、SMC等环境因子和Gs代表的植物内稳性对不同坡位花花柴光合特性的影响机制。【 结果】①花花柴的生长状况和环境参数、土壤水分和体积质量状况在不同坡位间存在显著差异（P<0.05），表现出明显的分异特征。②花花柴Pn、Tr、Gs日动态呈双峰曲线，Pn主、次 峰分别出现在10：00、18：00，存在“光合午休”现象，虽坡顶植株的WUE日均值（2.44 μmol/mmol）显著高于坡底 （2.05 μmol/mmol），但LUE日均值在坡位间并无显著差异。③不同坡位花花柴的光合参数与环境因子显著相关，其中坡底Pn与PAR、Ta呈显著正相关，与Ca显著呈负相关，而坡顶Pn仅与PAR和Ca显著相关；④不同坡位花花柴各环境因子对Pn的决策系数在坡底表现为Ca>PAR>Ta>SMC>RH，在坡顶表现为PAR>Ca>Ta>RH>SMC。【 结 论】新疆卡拉麦里山丘陵地带典型沟谷区不同坡位花花柴的光合特性受环境因子限制，主要表现为坡位间的PAR、Ca、Ta差异和水分限制下的Gs差异，形成了花花柴光强-土壤水分-气孔导度协同驱动的光合特性坡位分异。 |
| 关键词: 卡拉麦里山 花花柴 光合特性 坡位 环境因子 |
| DOI：10. 13207/j. jnwafu. 2026. 08. 008 |
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| 基金项目:新疆维吾尔自治区林业发展专项（XJLYKJ-2023-06，XJLYKJ-2024-01）；湖北省重点研发计划援疆项目（2023EGA123） |
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| Photosynthetic diurnal variation characteristics of Karelinia caspia on different slopes of Karamaili Mountain and its relationship with environmental factors |
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LUO Linglü1,2, SUN Gang3, WANG Xu3, XIE Lijie4, PENG Huangye1,2, YAN Caiyu1,2, HAN Wei1,2
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1.College of Geographic Science and Tourism，Xinjiang Normal University，Urumqi，Xinjiang 830054，China;2.Xinjiang Key Laboratory of Lake Environment and Resources in Arid Zone，Urumqi，Xinjiang 830054，China;3.Institute of Landscape Gardening，Xinjiang Academy of Forestry Sciences，Urumqi，Xinjiang 830000，China;4.Animal Husbandry and Aquatic Development Service Center，Fifth Division of Xinjiang Production and Construction Corps，Shuanghe，Xinjiang 833408，China
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| Abstract: |
| 【 Objective】The study aims to investigate the variation in photosynthetic characteristics of the desert plant Karelinia caspia across different slope positions，and to explore the factors and underlying mecha-nisms driving such variation，thereby providing insights for vegetation restoration in arid regions.【Method】With mature K. caspia individuals from both the valley floor and the summit of a typical gully in the Karamay Hills，Xinjiang，as the research subjects，using an LI-6400XT portable photosynthesis system，photosynthetic param-eters-including net photosynthetic rate（Pn），transpiration rate（Tr），intercellular CO2 concentration（Ci），stoma?tal conductance（Gs），leaf temperature（Tl），and leaf vapour pressure deficit（VPD） along with environmental factors such as photosynthetically active radiation（PAR），air temperature（Ta），relative humidity（RH），and at-mospheric CO2 concentration（Ca），were monitored over nine time periods across three consecutive clear days for six adult plants at each slope position. Simultaneously，soil moisture content（SMC） and soil bulk density （Pb） were measured using aluminium boxes and ring knife methods. Stomatal limitation（Ls），water use efficiency（WUE），and light use efficiency（LUE） were subsequently calculated. Variance analysis，correlation analysis，regression analysis，and path analysis were performed on the relevant indicators to investigate the mechanisms through which environmental factors（PAR，Ta，Ca，RH，SMC） and plant internal stability，repre-sented by stomatal conductance，influenced the photosynthetic characteristics of K.caspia across different slope positions.【Result】① The growth status of K.caspia，along with environmental parameters，soil moisture，and bulk density，showed significant differences（P<0.05） between slope positions，exhibiting clear divergent char-acteristics. ② The diurnal variations in Pn，Tr，and Gs displayed a bimodal curve，with the primary and secondary peaks of Pn occurring at 10：00 and 18：00，respectively，indicating a photosynthetic‘ midday depression’. Although the mean daily WUE at the slope top（2.44 μmol/mmol） was significantly higher than that at the slope bottom（2.05 μmol/mmol），the mean daily LUE did not differ significantly between slope positions. ③ Photo-synthetic parameters of K.caspia were significantly correlated with environmental factors at different slope positions. At the slope bottom，Pn showed significant positive correlations with PAR and Ta，and a significant nega-tive correlation with Ca.At the slope top，Pn was only significantly correlated with PAR and Ca. ④ The decision coefficients of environmental factors affecting Pn varied with slope position：at the slope bottom，the order was Ca>PAR>Ta>SMC>RH，while at the slope top，it was PAR>Ca>Ta>RH>SMC.【Conclusion】The photo?synthetic characteristics of K.caspia at different slope positions within a typical gully area of the Karamay Hills in Xinjiang are influenced by environmental factors. This influence is mainly reflected in differences in PAR，Ca，and Ta between slope positions，as well as variations in Gs under soil moisture constraints. These factors collec-tively drive slope-specific differentiation in photosynthetic traits through the synergistic effects of light intensity，soil moisture，and stomatal conductance. |
| Key words: Kalamaili mountain Karelinia caspia photosynthetic characteristics slope positions environ‑mental factors |
