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SCI论文目录 |
长白山阔叶红松林林冠/大气、土壤/大气生态界面结构及主要交换过程 |
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| 出 版 社：论文 |
| 发表时间：null |
| 台 站：
长白山森林生态系统定位研究站
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| 作 者：张军辉 |
| 点 击 率：10569 |
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| 关 键 字：界面生态学,过程分析,冠层/大气生态界面,土壤/大气生态界面,相干结构,界面结构 |
摘 要：界面生态学是一门新兴的生态学分支学科，其主要任务是以系统的生态界面为研究对象，研究其结构功能，重点解决界面生态过程的动力学机制。本文以长白山阔叶红松林为例，解决了林冠/大气、土壤/大气生态界面结构和过程的动态监测技术，建立了林冠/大气、土壤/大气生态界面诊断方法，刻画了其平均结构与时空特征；使用图示技术和子波辨识方法分析了林冠/大气生态界面交换的主要过程-相干结构的时空结构、猝发规律及其表现；初步分析了生长季节土壤/大气生态界面交换机制。
林冠/大气生态界面核心区域为16-32m；界面上界变化最大，下界变化很小，生长季节尤为如此；界面呈不对称结构，大气系统一侧厚度大于冠层一侧；生长季节的界面厚度大于非生长季节；界面结构有显著日动态。
相干结构主要周期30~60秒；水平尺度约为1~5倍平均冠层高度；猝发周期和猝发频率随冠层整体风速切变增大逐渐趋近于常数：20s，50次/半小时；80%以上的相干结构可以影响整个林冠流场，生长季节只能在生态界面内发挥重要作用，对交换的贡献率在70%以上，入侵概率在50%以上；3m处的入侵概率仅为0.05%，对动量和感热输运贡献率仅为35%和10%。
土壤/大气生态界面的核心范围为0-0.5m，土气界面处的物质能量输运以局地湍流输送为主体。
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关 键 字(英文)：Interface ecology; Process analysis; canopy/atmosphere ecological interface; soil-atmosphere ecological interface; interface structure; coherent structure
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摘 要(英文)：Interface ecology is a newly developed branch of Ecology. Taking the ecological interface between systems as its research object, It emphasis on Structure and function of ecological interfaces, dynamics mechanism of ecological processes across interfaces.
The characteristics of this thesis are: 1) a new technique to dynamically measure structure and processes across canopy-atmosphere and soil-atmosphere ecological interfaces was established; 2) the average structure and spatio-temporal variation of canopy- atmosphere and soil-atmosphere ecological interfaces were described. 3) Using techniques of visualization and wavelet transformation, spatio-temporal structure, law and contributions to moment and sensible heat exchange of coherent structure, the dominant exchange process across canopy-atmosphere ecological interface, were explored; 4) pilot study on the exchange mechanism across soil- atmosphere ecological interface was made.
Core zone of canopy-atmosphere ecological interface lies between 16m and 32m. Height of top borderline show a great variety, while the below boundary varies less. The interface is asymmetrical; part near atmosphere is thicker than that near canopy. Interface thickness of growing period is thicker than that of growth-stopped period. Structure of ecological interface shows an obvious daily pattern.
Duration of dominant coherent structure lies in the range 30s ~ 60s; stream-wise length is about 1~5 times of average canopy height; duration and frequency of occurrence approach to constants along with bulk mean wind shear: 20s and 50 per half hour; above 80 percentage of coherent structures can effect the fluid field within canopy, while they play the leading role in energy and matter transport only within the canopy-atmosphere ecological interface during growing period. Flux within the ecological interface contributed by coherent structures is about 70 percent and more. Flux of heat and moment near forest floor contributed by coherent structures is about 35 percent and 10 percent and less.
Core zone of soil-atmosphere ecological interface lies between 0m and 0.5m. Local turbulence plays the leading role in energy and matter transportation
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