Plant ecophysiolgy has a crucial role in understanding the ecological behavior of plants in their natural habitats by focusing on the resource acquisition and utilization which can be found in physiological and morphological responses to environments. Photosynthesis and respiration of plants result in temporal changes of CO2 flux and budget of ecosystems. The challenges to observe their dynamics, understand the mechanisms and predict the future changes would be achieved by cross-scale and multi-disciplinary research. Here I will (1) introduce the multidisciplinary efforts to understand the ecophysiological processes involved in the temporal dynamics of forest canopy photosynthesis at Takayama site, a deciduous broadleaf forest ecosystem located in a mountainous landscape in central Japan, and then (2) show how we extend our ecosystem study and what we focused on by linking plant ecophysiology and remote sensing as a new interdisciplinary approach "Satellite Ecology (SATECO)", and finally (3) introduce some current activities in networking to observe ecosystem functions and biodiversity under climate change. The series of studies introduced in this paper have been conducted with Hibiki M. Noda, Taku M. Saitoh, Shin Nagai and Kenlo N. Nasahara.