耐荫树种与不耐荫树种相比,其光合作用在较低的温度和较少的光照条件下就开始。随着光照的增加,耐荫树种能以较低的光强达到最大的光合作用率,而不耐荫树种则不能。随着光照的持续增加,就出现相反情况。不耐荫树种能响应光照的持续增加,比耐荫树种达到更大的光合作用率,而耐荫树种则不能。一般说来,空旷地上的不耐荫树种比耐荫树种生长快。随着荫蔽的形成,两者的生长差异缩小。当荫蔽增加到一定程度时,耐荫树种的生长将超过不耐荫树种。选择人工更新方式时,应考虑树种的适光性及其随竞争和光照而形成的生 Shade-tolerant species and shade-tolerant species, its photosynthesis at a lower temperature and less light conditions began. With the increase of illumination, shade-tolerant species can achieve maximum photosynthesis rate with lower light intensity, but not shade-tolerant species. As the light continues to increase, the opposite occurs. The shade-tolerant tree species can respond to the continuous increase of light, achieve greater photosynthetic rate than the shade-tolerant tree species, while the shade-tolerant tree species can not. In general, the shade-tolerant species on the open ground grow faster than shade-tolerant species. With the formation of shadows, the difference in growth between the two narrows. When shading increased to a certain extent, shade-tolerant species will grow more than shade-tolerant species. When choosing a man-made update, consideration should be given to the suitability of the tree species and their resulting competition and light