未来气候变化条件下青藏高原多年冻土区潜在植被类型面积预估

Areas prediction of potential vegetation types in thepermafrost zones of Qinghai Tibetan Plateauunder different climate scenariosin 2050 and 2070

摘要:

在青藏高原多年冻土区根据490个植被调查样点数据和3种遥感数据集的27个变量,利用决策树分类模型,模拟出4种代表性浓度路径情景下10个气候系统模式在2050年和2070年的青藏高原高寒草地类型(高寒沼泽草甸、高寒草甸、高寒草原、高寒荒漠和裸地)潜在分布结果。同时为保证数据分析的一致性,利用数据对当前高原草地类型也进行了反演。结果表明:相比当前高寒草地分布面积,预计在2050年和2070年裸地和高寒草甸面积微弱减少,高寒草原和高寒荒漠面积在微弱增加,高寒沼泽草甸面积变化不明显。结果在4种代表性浓度路径情景下的表现基本一致,研究不仅可以为高寒草地气候变化研究提供植被类型相关的数据支持,还可以为青藏高原多年冻土区碳循环的探讨提供部分的方法和理论依据。

Abstract:

Study of alpine grassland in permafrost zones of Qinghai-Tibetan Plateau has been widely concerned.As the climate warming,researches of alpine grassland types were rarely reported in this region.In this paper,there were 490 vegetation investigation samples and 27 variables derived from 3 remote sensing datasets.Used decision-tree classification model,the distribution of potential vegetation types was predicated by 10 climate system models under 4 climate scenarios in 2050 and 2070.There were alpine swamp meadow,alpine meadow,alpine steppe,alpine desert and barren land in the result of potential distribution.Meanwhile,the current distribution of alpine grassland types was developed for data analysis.The results indicated that in 2050 and 2070 area of bare land and alpine meadow slightly decrease,area of alpine grassland and alpine desert slightly increase and area of alpine marsh meadow did not significantly change in comparison with the current alpine grassland distribution area.The results were basically similar for 4 representative concentration pathways.This study could not only provide data support for the research on alpine grassland climate change,but also provide different methods and tools for exploration carbon cycle in permafrost zones of Qinghai-Tibetan Plateau.