Keywords :
Canopy conductance; Stomatal optimization; Soil moisture; Photosynthesis model
บทคัดย่อ :
Marginal water-use efficiency plays a critical
role in plant carbon-water coupling relationships. We
investigated the ecosystem marginal water-use efficiency (k) of a tropical seasonal evergreen forest to (1) determine the general pattern of k across time, (2) compare different models for calculating k, and (3) address how k varies with
soil water content during different seasons. There was a U-shaped diurnal pattern in k, which was higher in the
early morning and late afternoon. At other times of the day, k was lower and remained constant. Ecosystem k was higher in the wet season than in the dry season. All three models successfully captured the diurnal and seasonal patterns of k but differed in the calculated absolute values. The idea that k is constant on a subdaily scale was partly supported by our study, while a constant k was only true when data from the early morning and late afternoon were not included. The k increases with soil water content on a
seasonal scale, possibly because early morning k remained low in dry conditions when the soil water content was low.
เอกสารอ้างอิง :
Chen, M., Wang, G., Zhou, S., Zhao, J., Zhang, X., He, C., ... & Tan, Z. (2018). Studies on forest ecosystem physiology: marginal water-use efficiency of a tropical, seasonal, evergreen forest in Thailand. Journal of Forestry Research, 30(6), 2163-2173.
