大兴安岭地区不同海拔高度木本植物物候期及其对气候变化的响应

Phenological Characteristics of Representative Woody Plants at Different Altitudes in Daxinganling Region and Their Response to Climate Change

利用1995~2019年大兴安岭地区不同海拔高度上3个农牧业气象观测站(扎兰屯市、额尔古纳市、鄂温克旗)的6种典型木本植物物候期和同期温度观测资料,统计分析了其变化特征及相互影响。结果表明:(1)大兴安岭不同海拔地区表现出不同的温度变化趋势,年平均最低气温的下降趋势导致3个地区平均气温略降或上升趋势不明显。随着海拔高度的增加,升温趋势占据主导地位,且气温升幅大值区随海拔高度的增加而延后。(2)研究区域木本植物物候期存在较大差异,同一地点的物候期变化趋势基本一致,不同海拔地点则存在明显的差异,低海拔和中低海拔地区木本植物的春季和秋季物候期普遍推迟,高海拔地区的木本植物物候期普遍提前。(3)木本植物展叶始期随春季及年均气温的升高呈提前趋势,低海拔和高海拔地区木本植物受春季气温影响显著,中低海拔地区木本植物与各时段气温相关性较弱。落叶末期随气温变化趋势基本一致,但也存在明显的区域性特征,中低海拔地区落叶末期对气温变化的响应较为敏感。随着气温的升高,低海拔地区木本植物生长季天数对气温的响应一致,随着海拔的升高,气温对不同木本植物生长季天数变化的影响存在的差异较为复杂。说明大兴安岭地区不同海拔高度的气温及其变化趋势存在较大差异;各代表站典型木本植物的物候期和生长季对气候变化的响应不同。

Based on the observation data of phenology and temperature of six typical woody plants at three agricultural and animal husbandry meteorological stations(Zhalantun City,Ergun City and Ewenki Qi)at different altitudes in Daxinganling from 1995 to 2019,the characteristics of their changes and their interaction were analyzed statistically.The results showed that:(1)There are different temperature trends at different altitudes in Daxinganling,the annual mean temperature of the five ridges decreased slightly,the downward trend of the annual mean minimum temperature results in the slight decrease or inconspicuous upward trend of the average temperature in the three regions.With the increase of altitude,the trend of temperature rise is dominant,and the area of temperature rise is delayed with the increase of altitude.(2)There are great differences in the phenological periods of woody plants in the study areas.The change trends of phenological periods are basically the same at the same site,but there are obvious differences in different altitude sites,the phenological periods of woody plants are generally delayed in low middle-low elevation areas in spring and autumn,while those are generally advanced in high elevation areas.(3)The beginning period of leaf unfolding of woody plants shows an advance trend with the increase of Spring and annual average temperature,the woody plants are significantly affected by spring temperature in low and high altitude areas,and the correlation is weak between woody plants and temperature in middle and low altitude areas.The trend of the late defoliation is consistent with the temperature,but there are obvious regional characteristics.The response is sensitive of the late defoliation to the temperature in the middle and low altitude area.With the increase of temperature,the response is consistent of woody plant growing season days in low altitude area.With the increase of altitude,the effect is complicated of temperature on the change of woody plant growing season days.The study showed the obverse variation of temperature change at three different stations.The responses of woody plants to climate change are different.