Variation in Forest Structure and Transpirational Water Use in Korea
TERRECO Cluster F-06
From 12/2011Principal Investigator: Dennis Ochuodho Otieno, John Tenhunen, Björn Reineking, Sinkyu Kang
Staff: Thinh Duy Nguyen
Abstract: Water scarcity is one of the most sensitive societal problems worldwide and water use by natural and planted forest ecosystems has become a central subject in current research agendas. Forests play a critical role in the hydrological cycle making the study of water use by trees and forest stands of prime importance in the global change context. Intra- and inter-specific differences in both physiology and morphology exert a large but not well understood influence on the water balance of forest ecosystems. Stand structure and composition influences rainfall interception, runoff and water fluxes of the whole ecosystem. The aim of this study is investigate how species composition, tree canopy status and species specific sensitivity to key environmental drivers influence water use by forests. Mechanisms that influence water use by forest tree species, relevance of tree size and age, along with forest stand characteristics, in conditioning water use and the impact of different silvicultural practices and forest management on the water resource will be investigated. These investigations will assist in identifying parameters needed for easy and accurate up-scaling of water use from single trees to forest stand and then to landscape levels. Tree transpiration measurements will be carried out in different forest types in small sub-catchments of the Soyang Watershed, namely Haean, Simjukri and Gaari. Sapflow measurement techniques will be employed to measure tree transpiration in different tree species. In each forest type, stand structure characteristics (tree species, tree diameter at breast height (DBH), species composition and tree/stand density) will be described in detail to enable the up-scaling of transpiration from single trees to forest stand level. Key environmental parameters that influence tree transpiration will be assessed to allow for possible landscape level up-scaling of forest water use with LandClim. Thus the study will provide basic data on forest transpiration and forest structure characteristics of the different forest types found in the varying ecological zones and examine whether forests respond in a similar fashion to climate. Combined with other data sources, the study will help to define hypotheses related to forest water use and global change phenomena.
Key Words: forest water balance, transpiration, deciduous forest, mixed forest, conifer forest, LandClim
