Effect of Surface Vegetation Type on Soil Water Movement

• Main Authors: Chun-Hao Lin, 林軍豪
• Other Authors: 林俐玲
• Format: Others
• Language: zh-TW
• Published: 2006
• Online Access: http://ndltd.ncl.edu.tw/handle/27537744893043319133

碩士 === 國立中興大學 === 水土保持學系所 === 94 === To understand the relationship between different vegetation cover and soil moisture movement, Dataloggers and Watermarks have been both set up in two experimental areas, namely, forest area and grass area. One of the reasons that different vegetations influence soil water movement is different distribution of root system. Because there are more woody plants in forest area, the root system is distributed in deeper soil layer. No whether wet season or dry season, the soil water variation in 30 cm depth are larger than in 15 cm depth. Herb is the most vegetation cloak in grass area, so the soil water variation is huge in shallow layer of soil. Therefore, the range of soil water variation from heavy to light arrange for depth of 15cm, 30cm, 60cm, and 90cm. In the study of the situation of soil water movement during the rainfall, it is found that soil doesn’t wet downward each time. When the rainfall intensity arrived 4.5 mm/hr in forest area or 9.0mm/hr in grass area , water moved through 15 cm depth and arrived the deep soil layer. This might be caused by soil piping which mainly formed from rotten root. In the study of the soil water recession variation, It is found that antecedent rainfall amount is the major factor that affect the slope of soil water recession and the hours of soil water maintained. The antecedent rainfall amount and the slope of soil water recession are in negative relation, and the antecedent rainfall amount and the hours of soil water maintained are in positive relation.