Special Collection: Gas fluxes and micrometeorology of agricultural ecosystems in Japan

Abstract

　The recent climate changes are largely affecting agricultural activity and production in Japan. Yield and quality losses are already reported for many cereals, fruits, and livestock. On the other hand, agriculture has contributed to accelerate the global warming through ongoing greenhouse gas emissions. The crop canopy temperature, which is determined through energy exchanges such as evapotranspiration, is one of the most important environmental factors that control crop growth and production. Climate near and within a crop canopy is generally unique compared with the climate well above the canopy. Greenhouse gases such as carbon dioxide, methane, and nitrous oxide are also exchanged through crop canopies. Quantification of those fluxes is necessary for planning the strategy to mitigate global warming. Therefore, many efforts have been made for understanding the phenomena and their underlying principles of crop micrometeorology and fluxes, and new findings have been reported in the Journal of Agricultural Meteorology. A turning point in this research field in recent decades is the release of commercial models of open-path gas analyzer and laser spectroscopic gas analyzer, which allowed researchers to carry out long-term and continuous observations of fluxes at both plot and ecosystem levels. Accumulation of new data and findings have been accelerated since then. Another progress in this research field includes the advancement of canopy micrometeorology and gas exchange models. With the recent rapid growth of machine learning techniques, new statistical model approaches, which do not assume the processes explicitly, are also emerging. As part of the activity of JapanFlux, this special collection, entitled “Gas fluxes and micrometeorology of agricultural ecosystems in Japan”, compiles original articles from a wide range of agricultural ecosystems and methodologies aiming at summarizing the advancement over the last 20 years in this research field. And it will provide a foundation towards robust and sustainable agriculture under future climate change in Japan.