过去50年气候变化下中国潜在植被NPP的脆弱性评价

NPP vulnerability of China's potential vegetation to climate change in the past 50 years

借助动态植被模型IBIS,首先模拟了过去50年(1961-2010年)气候变化下中国潜在植被NPP的动态变化,然后采用IPCC第五次评估报告选定的标准气候态时段(1986-2005年)平均气候状态作为"标准年气候",并将该气候条件下的潜在植被NPP作为评价基准。通过与基准进行比较,计算每一年潜在植被NPP的波动情况,进而评价该年的气候条件是否使潜在植被"不适应"以及"不适应"的程度,最后根据过去50年的"不适应"次数和程度综合判断气候变化下潜在植被NPP的脆弱性。评价结果显示:在过去50年的气候变化下,天山以南的暖温带荒漠生态系统、北方温带草原生态系统以及青藏高原西部的高寒草原生态系统更容易受到气候变化的不利影响,NPP呈现出较高的脆弱性;而大部分以森林为主的生态系统则不容易受到气候变化的影响,NPP脆弱性较低,其中以常绿阔叶林和针叶林为主的生态系统NPP脆弱性更低。此外,天山以北的温带荒漠生态系统以及青藏高原中部和东部的高寒草原草甸生态系统NPP也呈现出较低的脆弱性。

By using the IBIS, a dynamic vegetation model, this study firstly simulated the NPP dynamics of China＇s potential vegetation in the past 50 years（1961- 2010）. Then according to the Fifth Assessment Report by IPCC, this study used the average climate conditions during1986- 2005 as the ＂standard climate＂, and took the NPP of the potential vegetation in this climate condition as the evaluation basis. Compared with the evaluation basis, the NPP fluctuation of each year was calculated to judge whether the potential vegetation adapts the climate change or not. Meanwhile, the degree of the inadaptability was evaluated. Finally, the NPP vulnerability of potential vegetation was evaluated by synthesizing the times and degrees of inadaptability to the climate change during the past 50 years. Results showed that： the NPP of the desert ecosystems south of the Tianshan Mountains, and the NPP of grassland ecosystems in northern China and western Tibetan Plateau were more likely to be impacted by the climate change in the study period. The NPP vulnerability of these ecosystems to climate change in the past 50 years was relatively high. The NPP of most of the forest ecosystems was not likely to be influenced by climate change. The NPP vulnerability to climate change of the evergreen broadleaved forests and coniferous forests was lower. Additionally, the NPP of the desert ecosystems north of Tianshan Mountains, and the NPP of the grassland ecosystems in the central and eastern parts of the Tibetan Plateau had lower vulnerability to climate change.