【摘要】 在大气 Ｃ Ｏ２ 浓度升高条件下采用水培方法对水稻根系生长及根系分泌物进行了初步研究。 Ｃ Ｏ２ 浓度倍增对水培水稻的根系生长具有明显的促进作用，约为７０％ ，但是根冠比却有所降低。水稻根系单位干重总有机碳、乙酸以及甲酸的释放量在 Ｃ Ｏ２ 浓度倍增条件下变化不明显，但是单株根系分泌物总量、乙酸以及甲酸的释放总量在 Ｃ Ｏ２ 倍增处理下明显增加。推测水稻根系分泌物的增加是高浓度 Ｃ Ｏ２ 下稻田 Ｃ Ｈ４ 排放增加的重要原因之一。更多还原

【Abstract】 Rice root growth and root exudation were studied using hydroponics under different atmospheric CO 2 concentrations Rice root growth was stimulated significantly by 70% under elevated CO 2 environment Total organic carbon,acetic acid and formic acid exudated per plant in a higher CO 2 concentration environment were significantly higher than those in ambient CO 2 environment,while the amounts expressed as per unit root dry weight showed no significant difference It is expected that the change of rice root exudate may be one important mechanism of CH 4 emission increase from rice paddies,under CO 2 enrichment更多还原