模拟林草模式不同遮荫条件下扁穗牛鞭草光合生理特征研究

A Study of the Photosynthetic Characteristics of H.compressa(L.f.) under Different Shading Environments

不同遮荫梯度下扁穗牛鞭草(H.compressa(L.f.))的最大净光合速率分别为全光照的84.2%、66.8%、44.3%、42.5%,且长期在遮荫条件下生长的扁穗牛鞭草叶绿体微结构或叶绿素含量可能发生了一定程度的变化;遮荫16%和48%时扁穗牛鞭草的表观光合量子速率(AQY)略大于全光照下的值,扁穗牛鞭草有基本适应此环境的趋势和可能,初步结论显示,48%及其以下的遮荫度范围在林草模式植被恢复上是可以参照的指标。

Different shading environments were simulated to analyze their influence on the net photosynthetic rate （Pn） ofHemarthria compressa （L. f. ） . Comparing the Pn under 79% - 16% shading environment with that under no shading, the rate is 42.5% -84.2%. Maybe the chloroplast structure and chlorophy 1 content have changed while growing under the shading environment for a long time. The AQY with the shading degrees of 16% and 48% are a little higher than open light environment＇s. These have shown that the H. compressa （L. f. ） can be adapted for this shading environment. This experiment also shows the shading degree of 48% can be taken as the index in vegetation restoration of tree ＋ grass model.