不同土壤之地溫、水分與熱流之變化

Variations in Soil Temperature, Moisture and Heat Flux of Different Soil Types

徐森雄(Sen-Hsiung Hsu) ； 蔡奉廷(Feng-Ting Tsai) ； 楊婉嘉(Wan-Jia Yang) ； 曾金楷(Jin-Kai Tzeng) ； 吳建賢(Jian-Shian Wu)

《作物、環境與生物資訊》 2卷3期 (2005/09) Pp. 201-210

https://doi.org/10.30061/CEB.200509.0003

摘要

This study was conducted near the meteorological station of National Pingtung University of Science and Technology, by setting a pile of soil and using wooden stakes to divide it into four equal plots. Each squared plot was filled with red soil, mudstone, yellow soil, or sand. Based on the observation from Sep. 2002 to Dec. 2003, the obtained results can be summarized as follows. The specific heat of mudstone was 0.19 calg^(-1)℃^(-1), which was about 0.5 times smaller than other kind of soils. The heat flux of mudstone with low specific heat was usually 0.5 times smaller than yellow soil and red soil, and 0.3 times smaller than sand. But its temperature was unstable. After the rainfalls, the speed to reach soil moisture saturation was in order of red soil＞mudstone＞yellow soil＞sand. From June 23, 2003 to July 13, 2003, the time needed to recover back to the moisture content before the rainfall for each type of soil in 5 cm depth was in order of red soil (100 hr)＞yellow soil (87 hr)＞mudstone (76 hr)＞sand (72 hr). Increase the percentage of moisture content in soil will increase the thermal conductivity of all soils. In this study, there was a liner relationship between the thermal conductivity and soil moisture in red soil, yellow soil, and sand. After the rainfalls, the heat flux of all soils, increased significantly with red soil increased the most. Although the moistness would increase the overall specific heat in soil, it would not simply increase the soil temperature.

關鍵字

地溫 ； 土壤水分含量 ； 熱通量 ； 比熱 ； 孔隙率

並列摘要

This study was conducted near the meteorological station of National Pingtung University of Science and Technology, by setting a pile of soil and using wooden stakes to divide it into four equal plots. Each squared plot was filled with red soil, mudstone, yellow soil, or sand. Based on the observation from Sep. 2002 to Dec. 2003, the obtained results can be summarized as follows. The specific heat of mudstone was 0.19 calg^(-1)℃^(-1), which was about 0.5 times smaller than other kind of soils. The heat flux of mudstone with low specific heat was usually 0.5 times smaller than yellow soil and red soil, and 0.3 times smaller than sand. But its temperature was unstable. After the rainfalls, the speed to reach soil moisture saturation was in order of red soil＞mudstone＞yellow soil＞sand. From June 23, 2003 to July 13, 2003, the time needed to recover back to the moisture content before the rainfall for each type of soil in 5 cm depth was in order of red soil (100 hr)＞yellow soil (87 hr)＞mudstone (76 hr)＞sand (72 hr). Increase the percentage of moisture content in soil will increase the thermal conductivity of all soils. In this study, there was a liner relationship between the thermal conductivity and soil moisture in red soil, yellow soil, and sand. After the rainfalls, the heat flux of all soils, increased significantly with red soil increased the most. Although the moistness would increase the overall specific heat in soil, it would not simply increase the soil temperature.

並列關鍵字

Earth temperature ； Soil moisture content ； Heat flux ； Specific heat ； Porosity