PARENT SESSION
Poster Session 24: Agro-Ecology
Wednesday, August 10, 5:00 PM - 6:30 PM, Exhibit Hall 220 A-E, Level 2, Palais des congrès de Montréal
Crop productivity and trace gas emission in agricultural ecosystems: The Agricultural Ecosystem Model (AEM) and its applications to China.
Ren, Wei1, 2, Tian, Hanqin*,2, Liu, Mingliang2, Melillo, Jerry 3, Reilly, John3, 1 Institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, PR China;, Beijing, China2 School of Forestry and Wildlife Sciences, Auburn University, Auburn, AL, USA3 The Ecosystem Center, Marine Biological Laboratory, Woods Hole, MA, USA
ABSTRACT- We have developed the Agricultural Ecosystem Model (AEM), which fully couples major biogeochemical cycles with hydrological cycles at a daily time step, as a tool for investigating how changing climates, land management and fertilization has affected crop productivity and exchanges of trace gases (CO2, CH4 and N2O) between agroecosystems and the atmosphere. The AEM has been calibrated against field data from Chinese Ecosystem Research Network. We have used this calibrated AEM to examine how crop productivity and carbon storage have changed as a result of multiple stresses and interactions among those stresses including climate variability, atmospheric composition (carbon dioxide and tropospheric ozone), precipitation chemistry (nitrogen composition), and agronomic practices. Our preliminary results show substantial year-to-year variations in crop yield as a result of seasonal and interannual climate variability. Irrigation and fertilization are primary controls over trace gas emission. Tropospheric ozone could lead to a 10-20% mean reduction of crop yield.
Key words: Agroecosystem, Ecosystem modeling, Trace gas, carbon sequestration