PARENT SESSION
Poster Session: Qualitative Relationships Between Landscape Processes and Patterns

Landscape patterns of ecosystem net primary productivity: A case study in the Changbai Mountain, China. ^*ZHANG, NA ¹, ^*ZHAO, SHIDONG ², ^*YU, ZHENLIANG ³ and ^*YU, GUIRUI ⁴, ¹ College of Earth Sciences, Graduate School of the Chinese Academy of Sciences, 19A Yu Quan Road, P.O.Box 3908,, Beijing, Beijing, P.R. China² Chinese Ecosystem Research Network, Institute of Geological Sciences and Resources Research, CAS, NO. 3a, Datun Road,, Beijing, Beijing, P.R. China³ National Natural Science Foundation of China, NO. 83, Shuangqing Road, Haidian Area,, Beijing, Beijing, P.R. China⁴ Chinese Ecosystem Research Network, Institute of Geological Sciences and Resources Research, CAS, NO. 3a, Datun Road,, Beijing, Beijing, P.R. China

ABSTRACT- Understanding how landscape pattern affects ecosystem processes is a fundamental question in landscape ecology. Based on existing theories and models in ecology, biogeochemistry and hydrology, a multiple-scaled, process-based spatial model (EPPML) has been developed for investigating the landscape pattern of ecosystem productivity in the Changbai Mountain Nature Reserve in northeastern China. EPPML incorporates heat transfer processes, plant physiological processes, carbon and water cycling processes. EPPML is run at fine spatio-temporal resolutions, and scaled up to the landscape scale using remote sensing, geographical information system (GIS) and land surface data. The estimated mean NPP for all vegetation types in the reserve is 0.680 kgC×m^-2×yr^-1. The mixed broad-leaved and Korean pine (Pinus koraiensis) forests have the highest NPP (1.084 kgC×m^-2×yr^-1). The total NPP for the entire reserve is 1.332 MtC×yr^-1. Our study shows that ecosystem productivity is highly correlated with LAI (R = 0.81) and transpiration (R = 0.77). The relationship between NPP and LAI seems linear when LAI is low, but becomes nonlinear as LAI is greater than 4∼5 m²×m^-2. However, soil water content is negatively correlated with NPP (R = -0.65) maybe because of the excessive soil water in the area. Our results indicate that the Changbai Mountain ecosystem functions as a carbon sink, with a biomass accumulation of about 1.058 MtC×yr^-1. The mixed broad-leaved and Korean pine forests and spruce (Picea asperata)–fir (Abies nephrolepis) forests have the largest increments: 0.452 and 0.339 MtC×yr^-1, respectively. The model predictions are supported reasonably well by the field observations. Nevertheless, further model validation and uncertainty analysis are needed in the future.

KEY WORDS: process-based spatial model, landscape pattern and process, net primary productivity, carbon and water cycles