在落叶季节,靠近路灯的树比起其他地方的树,叶子总是落得晚一些。这是怎么回事呢?原来,树木落叶需要形成一种脱落酸,脱落酸的形成又与太阳照射的时间长短有关。日照时间长,产生的脱落酸就少;日照时间短,产生的脱落酸就多。秋末冬初,日照时间缩短,脱落酸大量形成,树叶就纷纷飘落。但靠近路灯的树在日落以后继续享受灯光的照射,影响了脱落酸的形成,所以这些树落叶要晚一些。 During the deciduous season, the leaves near the street light tend to fall later than the trees elsewhere. What is going on? It turned out that the leaves need to form a kind of abscisic acid, the formation of abscisic acid and the length of time the sun irradiation. A long time sunshine, resulting in less abscisic acid; sunshine time is short, produce more abscisic acid. Early autumn and early winter, sunshine time shortened, a large number of abscisic acid formation, the leaves have fallen. However, the tree near the street lamp continued to enjoy the light after sunset, affecting the formation of abscisic acid. Therefore, the trees were later fallen.