关键词: 大气降尘, 大气降尘, 磁学特性, 污染, 西安市

Abstract: The paper aims to study the importance of plant community succession, ecosystem material cycle and climate change. We analyzed the phenological characteristics and its relationship with temperature of 5 woody plants including apricot tree, white poplar, white willow, mulberry tree and grape tree in Qiemo from 1981 to 2014 by using methods such as trend analysis, significance test and Mann-Kendall mutation test. The results showed that: (1) the phenological changes were characterized as: the leaf expansion and the beginning of flowering of apricot tree, white poplar, white willow, mulberry tree and grape tree were ahead of time, the leaf color change period was postponed, the end of flowering and the end of the leaves were different; the growing season of apricot, mulberry and grape tree were prolonged, that of white poplar and white willow were shortened slightly; (2) the phenological characteristics of apricot, mulberry and grape tree were significant, but that of white poplar and whitewillow were not significant; (3) the general trend of plant phenological changes was: the phenology in spring was in advance, the phenology in autumn was prolonged, the growing season was extended, and the plant phenological changes were consistent with the trend of temperature changes.