辽东栎对大气CO_2倍增的响应

THE RESPONSE OF QUERCUS LIAOTUNGENSIS TO DOUBLED CO2 CONCENTRATION

本文研究了ＣＯ２加浓对暖温带落叶阔叶混交林典型自然群落建群种辽东栎的影响，结果表明：在生理学方面，ＣＯ２倍增下气孔阻抗略增大，为对照的１０６％，蒸腾速率略下降，为对照的９２％，暗呼吸速率与对照很接近，但略微下降为对照的９８．９％。净光合速率、昼夜净光合量、水分利用效率都明显提高，分别为对照的１５５％，１７２％和１７９％。可以看出ＣＯ２倍增对辽东栎的生理过程有促进作用，属正效应。其中以生长旺季６、７月增长更为明显。在生长方面，ＣＯ２倍增下生长各项指标增长也较明显，叶面积为对照的１０７％，叶干重为对照的１４０％，以植株高度增加最明显，为对照的３３１％，清楚的看出辽东栎的生长与生理过程的变化趋势是一致的、均属正效应。也就是说在其他环境资源满足植物要求时，ＣＯ２倍增对树木具有“施肥”作用，它可促进植物的生理过程和提高其生物生产力。

The article deals with the effect of CO2 enrichment on the Ouercus liaotungensis,a dominant of typical and natural deciduous broadleaved mixed forests in the warm temperate China.The results show that the stomatal resistance,the transpiration rate,the dark respiration rate,the net photosynthesis rate,the diurnal net photosynthates and the water use efficiency of the plants grown under the CO2enriched environment were 106%,92%,989%,155%,172% and 179% of those grown under the CO2unenriched environment (CK),respectively.The response of the plants to the CO2 enrichment were more obvious in the growing peak period(June,July),in terms of the last three characters mentioned above.The leaf area,the leaf dry weight and the plant height of the plants growing under the CO2enriched environment were 107%,140% and 331% of those growing under CK,respectively.It is evident that the plants responded positively to the CO2enrichment in terms of most of the physiological and growth characters investigated,suggesting that,as long as other environment are proper for the plant,the doubled CO2 concentration may fertilize the plant and increase their physiological process and bioproductivity.