LEAF GAS EXCHANGE AND ISOPRENE EMISSION IN POPLAR IN RESPONSE TO LONG-TERM EXPERIMENTAL NIGHT-TIME WARMING AND SUMMER DROUGHT IN A FOREST-STEPPE ECOSYSTEM ArticleNogues I., Medori M., Fortunati A., Lellei-Kovács E., Kröel-Dulay G., Calfapietra C.Environmental and Experimental Botany. 2018.