Study on seasonal change of insolation in the forest stand

林分日照季节变化研究

• 批准号: 04660159
• 负责人: TAKEUCHI Kimio
• 金额: $ 1.28万
• 依托单位: Niigata University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1992
• 资助国家: 日本
• 起止时间: 1992 至 1993
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-04660159/
• 关键词: Bare land insolation; Forest stand insolation; PAR; Luminous intensity; Seasonal change; 固定プロット; 光量子センサー

1. By corresponding the insolation on the open building-top to the time progress of calculated solar altitude, the amount of insolation on the earth in fine weather was estimated. Although observing value includes atmospheric change, it is concluded that insolation can be estimated sufficiently on bare land in the fine weather daytime.2. Changes of insolation in various forest stands were measured. The monthly measurement in a fine weather was so difficult that measurements were not done many times in each forest stand. On earh forest stand, 20m x 20m square plot was set, and then the insolation was measured at 1.5 meters upper site of square points at the intervals of 5 meters. PAR(photosynthetically active radiation) and luminous intensity were measured using the LI-COR LI-1000 Data Logger with a PAR sensor and a luminous sensor.3. Based on the above-mentioned idea and method, seasonal change of insolation in the forest was estimated. Consequently, the calculated parameters have made the good estimations of insolation on bare land around the forest stand possible. Concerniing the point, this research will give a new view to usual method of measuring insolation. However, because of large variation of insolation in each point, seasonal changes could not be discussed sufficiently. In addition to improving the method, further measurements are planned for accumulating data as the development of this research.

1. 通过将开放式建筑顶部的日照量与计算出的太阳高度角的时间进程相对应，估算出晴天时地球上的日照量。虽然观测值包含了大气变化，但得出的结论是，在晴朗的白天，在裸地上可以充分估计日照。2．测量了不同林分的日照变化。好天气下的每月测量非常困难，每个林分都没有进行多次测量。在大地林分上设置20m×20m的方样地，每隔5米，在方点上部1.5米处测量日照量。使用带有PAR传感器和发光传感器的LI-COR LI-1000数据记录仪测量PAR（光合有效辐射）和发光强度。 3．基于上述思路和方法，对森林日照季节变化进行了估算。因此，计算出的参数使得对林分周围裸地的日照量进行良好的估计成为可能。关于这一点，本研究将为通常的日照测量方法提供新的视角。然而，由于每个点的日照变化较大，无法充分讨论季节变化。除了改进方法之外，随着这项研究的发展，还计划进行进一步的测量来积累数据。