ADAPTABILITY STUDY ON LEAF DEVELOPMENT OF GREENING TREE SPECIES TO COASTAL SALINE LAND

摘要

Changes in leaf development parameters can reflect the adaptive strategies of plants in the environment. In order to study the adaptability of greening tree species to coastal saline land, taking the greening tree species in coastal saline area as the study objects, we investigated the two processes of leaf emergence and leaf abscission and analysed the relationships among leaf life span, leaf emergence, and leaf abscission. We found that the leaf emergence process concentrated in the middle to late April. Soil salinity could delay leaf emergence process. Leaf abscission process lasted for a longer period and concentrated in the period from late November to late December. Soil salinity could promote the aging and abscission process of leaves. Leaf life span showed significant correlation with leaf abscission parameters. Greening tree species reduced leaf life span mainly through earlier beginning of leaf abscission, earlier ending of leaf abscission or shortening leaf abscission duration to adapt coastal saline land. According to leaf emergence time and leaf abscission time, greening tree species could be divided into four categories, and different categories of trees had different adaptive strategies.