大气一氧化碳浓度升高对植物生长的影响

大气ＣＯ２浓度同对植物生长有促进作用，对Ｃ３植物生长的促进作用最大。短期ＣＯ２浓度升高时，植物光和速率增加；在长期ＣＯ２浓度升高条件下，植物光鸽上降并发生光合适应现象。这可能是植物在长期ＣＯ２浓度升高条件下植物源库关系不平衡引起的反馈抑制作用以及营养吸收不能满足光合速率增加的需要所引起Ｒｕｂｉｓｅｏ活必和含量下降。在ＣＯ２浓度升高条件下植物的呼吸也会发生变化，根的分枝和数量增多，根系的分泌量和吸收

Effects of elevated atmospheric CO_2 concentrations on growth of plants

Elevated atmospheric CO 2 concentration can stimulate the growth of plants,especially C 3 plants.Plant photosynthesis could be stimulated under the short term CO-2 enrichment,but decreased and accompanied by the photosynthetic acclimation when exposed to long term elevated CO-2 concentration.This may be due to:(1) the feedback inhibition induced by the imbalance of source sink relationship;(2) The decrease of Rubisco content and activity caused by short of nutrient.Under the elevated CO 2 concentration,branches and number of roots,release of exudates,absorption of nutrient elements by roots,mycorrhiza infection rate and biomass of plants were increased.The ability resitant to O-3 injury of plant was inereased.The atmospheric temperature,nitrogen and phosphorus supply from soil could affect responses of plants to the elevated CO-2 concentration.