【作者】 王乾；

【导师】 吴宁； 罗鹏；

【作者基本信息】 中国科学院研究生院（成都生物研究所） ， 植物学， 2006， 博士

【摘要】 辐射传输研究是贯穿森林生态系统的纽带，太阳辐射为植物的生长发育提供光合能量、适宜的环境温度以及发育信息。一方面，气候变化使到达地面辐射能的质和量发生变化，影响到植被的生长发育，改变森林的结构，而森林结构的变化又会影响林冠内辐射能的分配和质量，这些变化会进一步影响到林下土壤温度，改变森林根系活性以及土壤营养转化的效率；连锁反应的结果有可能会使森林生态系统的生产力发生变化，改变碳素和氮素源库的调节方向，从而反馈影响地球气候系统。另一方面，人类作为生态系统的成员，必然需要森林生态系统为其提供更多的原材料和更好的生态服务功能，如何实现这些目标，就需要人类适度调整干预方式和频度，达到预期的目的。本文在建立适合于川西亚高山森林的叶面积测量技术、光照辐射模型和土壤温度变化模型的基础上，对川西亚高山地带森林生态系统的辐射传输特征进行了分析，并从森林结构的角度探讨了林分内的辐射分布以及对土壤温度的影响。主要成果如下： 1．提出了一种照相法测量叶面积的方法。通过对摆放在平面上的叶片照相，利用投影变化，把非正射图像转化为正射图像，然后经过计算机图像处理得到每一片叶片的面积、周长、长度、宽度等信息。这种方法可使用户以任意方向和距离拍摄处于平面上的叶片，能同时处理大量的叶片，适于野外离体或活体叶片测量。叶片面积分辨率可调，分辨率可以与常用的激光叶面积仪相近甚至更高，而且叶片图像可以存档查询。更多还原

【Abstract】 Radiative transfer plays a key role in forest ecosystems. Solar radiation provides energy for photosynthesis, appropriate ambient temperature and development information for plants. However, quality and quantity of radiation reaching land surface are affected by weather and subsequently influence the growth and development of plants, which in turn changes the budget of radiation in forest. Soil temperature changes with the variation of radiation under forest canopy and influences the activity of roots and rate of nutrient turnover. Thus, any changes of radiation will induce chain reactions in the entire ecosystem and display in the value of net primary productivity which will possibly shift the relationship between carbon source and sink at local or regional scale and feed back to the global climate system. On the other hand, as a component of ecosystems, human beings of course need to demand more materials and better service from ecosystems. For these purpose, man must adapt their pattern and frequency of interference to ecosystems. This paper aims to research on the canopy structure, the radiation distribution and their influence on soil temperature from the process of radiative transfer in subalpine forest ecosystem of western Sichuan. The main results are:1 Present a new photogrammetric method for leaf area. The main idea is to convert non-vertically taken images of planar leaves to orthoimages through projective transformation. The resultant images are used to get leaf morphological parameters through image processing. This method enables users to take photos at almost any orientation and distance if only the leaves are placed on same plane, and to process更多还原