气候变化对高海拔物种的生长影响较为显著,高海拔物种的时空分布直接影响区域生态平衡。基于新疆森林资源连续清查数据,使用一元生物量模型估测新疆天山及阿尔泰山西伯利亚落叶松生物量,计算其固碳速率,利用全局莫兰指数(Moran's I)和热点分析(Getis-Ord Gi*)研究新疆西伯利亚落叶松固碳速率空间聚集特征,并分析其近年来在空间上的变化趋势,再结合气象数据运用相关和偏相关分析,分析其空间分异的影响因素。结果表明:(1)天山东部西伯利亚落叶松固碳速率高于阿尔泰山西伯利亚落叶松固碳速率,20012016年期间,新疆西伯利亚落叶松固碳速率整体呈增长趋势,阿尔泰山西伯利亚落叶松固碳速率由0.43 t hm~(-2) a~(-1)增长至0.76 t hm~(-2) a~(-1),天山东部西伯利亚落叶松固碳速率由0.89 t hm~(-2) a~(-1)增长至1.06 t hm~(-2) a~(-1)。(2)天山东部西伯利亚落叶松固碳速率呈离散分布但不显著(P>0.05),阿尔泰山西伯利亚落叶松固碳速率空间聚集特征趋于显著,其高固碳速率逐渐从东南部的青河县向西北部的阿尔泰市和哈巴河县移动,而低固碳速率从阿尔泰山的西北部的阿勒泰市向东南部的青河县移动。(3)通过偏相关分析得出,20012016年时期新疆西伯利亚落叶松固碳速率与温度成极显著正相关(P<0.01),20012006年和20062011年时期与降水成正相关,但不显著,至20112016年时期转变为与降水成极显著正相关(P<0.01),20012016年期间,其与纬度梯度成极显著负相关(P<0.01)转变成无显著相关性,与海拔梯度无显著相关。新疆西伯利亚落叶松固碳速率与纬度梯度呈显著负相关的空间分布格局已发生显著变化,其空间分布格局由东南部高西北部低,逐渐变成西北部高东南部低。
英文摘要:
High-altitude species are more sensitive than low-altitude species to climate change,and the spatiotemporal distribution of species directly reflects environmental status and affects regional ecological balance.Based on continuous inventory data of forest resources in Xinjiang,we estimated the biomass of Larix sibirica in Xinjiang using a one-element biomass model and then calculated carbon sequestration rate (CSR).This study investigated the spatial agglomeration characteristics of CSR of L.sibirica in XinJiang in recent years by Getis-Ord Gi* and Moran' s I.Furthermore,the influential factors of spatial differentiation of CSR were analyzed in combination with the meteorological data and topographic data based correlation and partial correlation analysis.(1) The CSR of L.sibirica in the eastern Tianshan Mountains was higher than that of L.sibirica in the Altai Mountains,and the CSR of L.sibirica in Xinjiang increased from 2001 to 2016,the CSR of L.sibirica in the eastern Tianshan Mountains increased from 0.43 t hm~(-2) a~(-1) to 0.76 t hm~(-2) a~(-1),and the CSR of L.sibirica in the Altai Mountains increased from 0.89 t hm~(-2) a~(-1) to 1.06 t hm~(-2) a~(-1).(2) The CSR of L.sibirica in the eastern Tianshan Mountains was discretely distributed but insignificant (P >0.05).The spatial agglomeration of CSR by L.sibirica in the Altay Mountains was remarkable,and the high CSR gradually moved from the southeastern Qinghe County of Altay Mountains to Habahe County in the northwestern of Altay Mountains,whereas the low CSR moved from Altay City to Habahe County.(3) Partial correlation analysis indicated that the CSR of L.sibirica and temperature were positively correlated(P <0.01) from 2001 to 2016.From 2001 to 2006 and from 2006 to 2011,the CSR of L.sibirica was positively correlated with precipitation,although not significantly,but was both positively and significantly correlated with precipitation from 2011 to 2016 (P < 0.01).The correlation between CSR and latitude changed from negative and significant (P < 0.01) to not significant from 2001 to 2016.There was no significant correlation between CSR and altitude.From 2001 to 2016,the distribution of the significant negative correlation between CSR and latitude has changed greatly,and the spatial distribution of CSR has changed from southeastern higher northwest lower to the southeastern higher northwest lower.