Saturday, 15 July 2006
137-48

Soil Water Characteristics of Mixed Conifer and Deciduous Forest in Low Mountain Area in Beijing China.

Lishui Nie, Michigan State Univ, 4632 S. Hagadorn C-16, East Lansing, MI 48823

This research was aimed at to study the soil physical properties, the soil water characteristics and their influences on the plant available soil water. On site long term measurement and laboratory analysis was employed. By lab analysis it was showed that the soil had good physical properties as follows: bulk density is between 1.2`1.45 g/cm3, total porosity 45%`58% while the non capillary porosity 6%`10% and may leading the root in poor aeration. Strikingly different with the clayey soils the soil moisture characteristic curve went down very quickly as the suction increase in the low suction area (<3.0x105Pa) while in the high suction area (>3.0x105Pa) it was flat. The soil moisture characteristic curve could be described by the Gardner empirical equation ƒÆv=ƒŸS-B. The soil had water holding capacity of 418.77 mm while the field water holding capacity was 348.53 mm and the soil wilting capacity 31 mm. So the soil had a field water holding capacity of 346.8 mm. But on site study it was showed the actual water holding capacity never reached such high level. The actual water holding capacity was between 60-180 mm much lower than the field water holding capacity. There existed an about 50 days dry period from late of April to the early of June with the soil moisture lower or near 10%. There existed a humid period from July to early of September with a soil moisture between 20% to15%. Discussions was made on how to evaluate the soil wilting percentage in forest stand and suggestions was made to continuing further studies on it. Keywords: soil physical properties, soil moisture characteristic curve, soil wilting percentage, soil water holding capacity


Back to 2.1B Soil Hydrology, Structure, and Micromorphic Propoerties (Soil Porous System) - Poster
Back to WCSS

Back to The 18th World Congress of Soil Science (July 9-15, 2006)