Climate influences the demography of three dominant sagebrush steppe plants
Climate influences the demography of three dominant sagebrush steppe plants
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DOI：
10.1890/10-0780.1
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发表时间：
2011-01-01
期刊：
影响因子：
4.8
通讯作者：
Adler, Peter B.
中科院分区：
文献类型：
--
作者：
Dalgleish, Harmony J.;Koons, David N.;Adler, Peter B.
气候变化可能会改变优势物种的种群增长，从而对群落结构和生态系统动态产生深远影响。了解气候历史变化与人口活力率（生存、增长、补充）之间的联系是预测未来气候变化影响的一种方法。使用来自美国爱达荷州东部的独特的长期数据集，我们对 Pseudoroegneria spicata、Hesperostipa comata 和 Artemisia tripartita 的积分预测模型 (IPM) 进行参数化，以确定对人口增长最重要的人口比率和气候变量。我们使用包含气候变量的混合效应回归模型将生存、生长和补充描述为基因大小的函数。对于所有三个物种，籽粒的存活+生长部分的弹性均大于补充部分，存活+生长占总弹性的87-95%。每个物种中具有最高弹性值的基因大小非常接近存活率接近 100% 的基因大小阈值。我们发现气候对三个物种中的两个物种的人口增长率有很大影响。在 H. comata 中，上一年降水量减少 1% 将导致种群增长减少 0.6%。在 A. tripartita 中，夏季气温每升高 1%，种群数量就会增长 1.3%。在 H. comata 和 A. tripartita 中，气候对基因生长的影响大于对生存或补充的影响，从而影响了种群增长。冬末降雪是 P. spicata 最重要的气候变量，但其对种群增长的影响小于我们在 H. comata 或 A. tripartita 中发现的气候影响。对于所有这三个物种，人口统计反应滞后于气候至少一年。我们的分析表明，了解气候对基因生长的影响可能对于预测艾蒿草原植被结构和功能的未来变化至关重要。
Climate change could alter the population growth of dominant species, leading to profound effects on community structure and ecosystem dynamics. Understanding the links between historical variation in climate and population vital rates (survival, growth, recruitment) is one way to predict the impact of future climate change. Using a unique, long-term data set from eastern Idaho, USA, we parameterized integral projection models (IPMs) for Pseudoroegneria spicata, Hesperostipa comata, and Artemisia tripartita to identify the demographic rates and climate variables most important for population growth. We described survival, growth, and recruitment as a function of genet size using mixed-effect regression models that incorporated climate variables. Elasticites for the survival + growth portion of the kernel were larger than the recruitment portion for all three species, with survival + growth accounting for 87-95% of the total elasticity. The genet sizes with the highest elasticity values in each species were very close to the genet size threshold where survival approached 100%. We found strong effects of climate on the population growth rate of two of our three species. In H. comata, a 1% decrease in previous year's precipitation would lead to a 0.6% decrease in population growth. In A. tripartita, a 1% increase in summer temperature would result in a 1.3% increase in population growth. In both H. comata and A. tripartita, climate influenced population growth by affecting genet growth more than survival or recruitment. Late-winter snow was the most important climate variable for P. spicata, but its effect on population growth was smaller than the climate effects we found in H. comata or A. tripartita. For all three species, demographic responses lagged climate by at least one year. Our analysis indicates that understanding climate effects on genet growth may be crucial for anticipating future changes in the structure and function of sagebrush steppe vegetation.