Spatial and Temporal Variability of Soil Respiration Rate at a Small Watershed Revegetated with Japanese Cypress.

Topographical Effects on Soil Respiration in a Deciduous Forest-The Case of Weathered Granite Region in Southern Kyoto Prefecture-

“…The closed times for the automated and manual chambers were 12 or 30 min; these times are relatively longer than those in other studies (e.g., Mitani et al;, Kosugi et al, 2007. However, we confirmed that the CO2 concentration in the chamber increased linearly until it was less than 1300 ppm, after which the rate of increase in CO2 concentration tended to decrease .…”

“…While these areas have revegetated over the past 130 years, resulting in the current forest coverage, the forest soils are immature and contain very little organic carbon. Contrary to previous studies such as those by Jia et al (2003), Mitani et al (2006), and Kosugi et al (2007), Tamai et al (2005a) reported that soil respiration was lower in areas of higher topography due to drier soil in deciduous forests of the weathered granite region.…”

“…The slope heights in these studies varied widely between 7 and 120 m, and most of the studies reported that soil respiration rates were lower on the lower parts of the slopes. Jia et al (2003), Mitani et al (2006), and Kosugi et al (2007) noted that a higher soil moisture ratio is one of the reasons for decreased soil respiration on lower slopes.…”

“…Studies on the spatial variation of soil respiration on slopes have been performed in many forest types, including Japanese cedar forest (Ohashi et al, 2007), Japanese cypress forest (Mitani et al, 2006), mixed Japanese cedar and cypress forest (Shimono et al, 1989), deciduous broadleaf forest (Hanson et al, 1993;Jia et al, 2003), and tropical rainforest (Sotta et al, 2006;Kosugi et al, 2007). The slope heights in these studies varied widely between 7 and 120 m, and most of the studies reported that soil respiration rates were lower on the lower parts of the slopes.…”

Topographic variation in heterotrophic and autotrophic soil respiration in a tropical seasonal forest in Thailand

“…Shimada et al (1998) on the lower slope and 9.9 MgC ha À1 year À1 on the upper slope in a Japanese coniferous plantation. However, no correlation (Fang et al 2009), and the opposite trend, namely lower soil respiration rates on the lower slope and at the valley bottom than the upper slope (Chambers et al 2004;Tsutsumi et al 1985;Epron et al 2006;Mitani et al 2006;Kosugi et al 2007) have been reported in several forest ecosystems. Although many reports have suggested that soil respiration varies with slope position, no general principle concerning the relationship between slope position and soil respiration has yet been established.…”