Climate change may restrict dryland forest regeneration in the 21st century.
Climate change may restrict dryland forest regeneration in the 21st century.
复制标题
气候变化可能会限制21世纪旱地森林的再生。
作者：
M. D. Petrie;M. D. Petrie;J. Bradford;R. Hubbard;W. Lauenroth;C. Andrews;D. Schlaepfer
21世纪旱地森林的持久性和地理扩展将受到气候变化如何支持与树木更新相关的人口过程的影响。然而，气候变化可能改变再生的方式尚不清楚。本文建立了一个定量框架，估算了黄松这一重要的旱地森林物种的森林更新潜力（RP）作为关键环境条件的函数。我们综合了美国西部47个黄松林的气象数据和气候预测，并使用生态系统水平衡模型评估了RP。我们的主要目标是在历史、21世纪中期和21世纪后期的时间框架中对比支持再生的条件。未来的气候条件支持2020-2059年的RP比1910-2014年高50%。随着2060-2099年温度的大幅度升高，幼苗成活率下降，RP下降50%，极低RP年份的频率从25%增加到58%。因此，气候变化可能最初支持更高的RP，并增加成功更新事件的可能性，但最终将降低平均RP和温和气候支持更新的年份频率。我们的研究结果表明，仅气候变化就可能通过限制幼苗存活在21世纪后期开始限制旱地森林的持续和扩张。
The persistence and geographic expansion of dryland forests in the 21st century will be influenced by how climate change supports the demographic processes associated with tree regeneration. Yet, the way that climate change may alter regeneration is unclear. We developed a quantitative framework that estimates forest regeneration potential (RP) as a function of key environmental conditions for ponderosa pine, a key dryland forest species. We integrated meteorological data and climate projections for 47 ponderosa pine forest sites across the western United States, and evaluated RP using an ecosystem water balance model. Our primary goal was to contrast conditions supporting regeneration among historical, mid-21st century and late-21st century time frames. Future climatic conditions supported 50% higher RP in 2020-2059 relative to 1910-2014. As temperatures increased more substantially in 2060-2099, seedling survival decreased, RP declined by 50%, and the frequency of years with very low RP increased from 25% to 58%. Thus, climate change may initially support higher RP and increase the likelihood of successful regeneration events, yet will ultimately reduce average RP and the frequency of years with moderate climate support of regeneration. Our results suggest that climate change alone may begin to restrict the persistence and expansion of dryland forests by limiting seedling survival in the late 21st century.
DOI：
10.1073/pnas.0505734102
发表时间：
2005-10-18
影响因子：
11.1
作者：
Breshears, DD;Cobb, NS;Meyer, CW
通讯作者：
Meyer, CW