| 引用本文: | 牛永强,吴喆滢,徐文娴,等.马占相思幼树雨季液流速率对环境因子的响应[J].灌溉排水学报,0,():-. |
| NIU Yongqiang,WU Zheying,XU Wenxian,et al.马占相思幼树雨季液流速率对环境因子的响应[J].灌溉排水学报,0,():-. |
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| 摘要: |
| 【目的】旨在揭示幼龄马占相思液流速率变化特征及其与环境因子关系，为马占相思人工林可持续经营提供依据。【方法】2014年6–10月利用Dynagage包裹式液流传感器和DL2e环境因子测量系统，对海南西部人工林幼龄马占相思液流速率及主要环境因子进行连续监测，研究了幼龄马占相思液流速率变化特征其与环境因子的关系。【结果】晴天和阴天马占相思树干液流速率日变化总趋势基本相同，呈现出较快上升-峰值-波动下降的趋势，晴天、阴天日平均液流速率分别为3.07 mL/(cm2·h)和1.59 mL/(cm2·h)；而雨天液流速率变化较为平缓，变化规律不明显，日平均液流速率为0.78 mL/(cm2·h)。晴天马占相思液流速率最大值出现在9:00左右，“蒸腾午休”现象显著；而阴天、雨天液流速率最大值出现的时间延后，“蒸腾午休”不明显或不存在。晴天马占相思液流速率变化主要受饱和水汽压差、空气相对湿度、气温影响，阴天主要受气温、饱和水汽压差、光合有效辐射影响，而雨天主要受光合有效辐射和气温的影响。【结论】马占相思液流存在明显昼夜节律，液流速率峰值早于光合有效辐射峰值，且光合有效辐射越强，液流速率峰值出现时间越早；晴天、阴天、雨天3种天气条件下，对液流速率影响最大的环境因子分别为饱和水汽压差、气温和光合有效辐射。 |
| 关键词: 包裹式茎流传感器;马占相思;液流速率;环境因子 |
| DOI： |
| 分类号:S715.4 |
| 基金项目:海南省自然科学基金项目（420MS043）与国家自然科学基金项目（41361006） |
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| The Response of Young Acacia mangium Sap Flow Velocity to Environmental Factors in Rainy Season in Hainan |
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NIU Yongqiang1, WU Zheying2, XU Wenxian3, HAN Qi3, ZHAO Congju3
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1.Danzhou Forest Farm;2.School of Life Sciences,Hainan Normal University;3.School of Geography and Environmental Sciences,Hainan Normal University
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| Abstract: |
| 【Objective】 Revealing the characteristics of sap flow changes of young Acacia mangium and the relationship between sap flow and environmental factors provides a basis for the sustainable management of Acacia mangium plantations 【Method】 Danzhou Forest Farm located in the western Hainan Island was chosen as a research area, where the sap flow and environmental factors were continuously measured by Dynagage sap flow sensors and DL2e environmental data acquisition systems from June to October 2014. 【Result】 In sunny and cloudy days, the stem sap flow velocity of Acacia mangium exhibited similarly general trend of diurnal variations which rose rapidly to the peak value and then declined with fluctuations, and the daily average sap density was 3.07 mL·cm-2·h-1 and 1.59 mL·cm-2·h-1 respectively. However, in rainy days, the stem sap flow velocity varied more gently with a daily average value of 0.78 mL·cm-2·h-1 and did not show significant change patterns. The peak value of the sap flow velocity appeared in the morning about 9:00 in sunny days and the phenomenon of “transpiration plateau” was obvious. However, there was a delayed maximum value, and the “transpiration plateau” was not obvious or didn't exist in cloudy and rainy days. Path analysis showed that in sunny days the change of Acacia mangium sap flow velocity was mainly affected by water vapor pressure deficit (VPD), air relative humidity (RH), and air temperature (Ta), in cloudy days affected by Ta, VPD, and photosynthetically active radiation (PAR), and affected by PAR and Ta in rainy days. 【Conclusion】 The sap flow velocity of Acacia mangium shows obvious diurnal variation, and the peak value of sap flow is earlier than that of PAR, and the stronger the PAR, the earlier the peak of sap flow appears. In sunny, cloudy and rainy days, the dominant factors affecting the change of sap flow are VPD, Ta, and PAR respectively. |
| Key words: Dynagage sap flow sensors; Acacia mangium; sap flow velocity; environmental factors |
