Kenji Tsuruta, Motonori Okumura, Tomonori Kume, Ryuji Ichihashi, Yoshinori Shinohara, Yoshiko Kosugi
Received 2015/09/03, Accepted 2015/12/05, Released 2016/01/22

Kenji Tsuruta1), Motonori Okumura1), Tomonori Kume2), Ryuji Ichihashi3), Yoshinori Shinohara4), Yoshiko Kosugi1)

1) Graduate School of Agriculture, Kyoto University
2) School of Forestry and Resource Conservation, National Taiwan University, Taiwan
3) Faculty of Agriculture, Kagawa University
4) Faculty of Agriculture, Kyushu University

The expansion of Moso bamboo forests in Japan might change transpiration and therefore reduce the availability of water resources. Moso bamboo stands are often composed of culms with various ages and older culms may have lower sap flux density (Fd), which may in turn affect individual culm transpiration (Qt), probably because vascular bundles do not regenerate after sprouting. Information related to the differences of Fd and Qt between younger and older culms would be important for (i) understanding the effects of culm age structure changes on stand-scale transpiration (EC), and (ii) developing sampling strategies for EC estimates in Moso bamboo forests. We conducted sap flux measurements for 15 individuals from four culm age classes in a managed Moso bamboo forest in Kameoka, Kyoto, Japan. Differences in Fd were not significant among the four culm age classes with almost the same stem diameter at breast height (DBH). Qt was related to DBH across four age classes, indicating that culm age had no apparent effect on Qt in the forest. Our results suggest the effects of culm age structure changes on EC are small, and contribute to development of sampling strategy without considering culm age structure for EC estimates at this site.

[Full Text]

Copyright (c) 2016 Japan Society of Hydrology and Water Resources