Pollen productivity estimates from the forest—tundra ecotone in west-central Sweden: implications for vegetation reconstruction at the limits of the boreal forest
Pollen productivity estimates from the forest—tundra ecotone in west-central Sweden: implications for vegetation reconstruction at the limits of the boreal forest
复制标题
DOI：
10.1177/0959683607086769
复制
发表时间：
2008-02
期刊：
影响因子：
--
通讯作者：
H. von Stedingk;R. Fyfe;A. Allard
中科院分区：
文献类型：
--
作者：
H. von Stedingk;R. Fyfe;A. Allard
在北极和高山冻原，并在森林冻原交错带的化石花粉数据植被的成功重建，阻碍了低花粉生产的主要类群在这些环境中，可能占主导地位的背景花粉成分。从花粉数据中定量植被的新方法（REVEALS和LOVE模型）依赖于通过将花粉传播和沉积模型应用于现代花粉-植被调查工作来定量背景和当地花粉。迄今为止，这一新兴领域的研究主要集中在低地环境。本文介绍了花粉生产力估计（PPE）来自瑞典中西部的森林冻原交错带，讨论了在这种环境中的花粉（RSAP）的相关来源地区，并估计背景花粉的贡献。结果表明，在森林-冻原交错带，藓类植物的RSAP为c。500米，主要森林苔原交错带类群的PPE显示出显着的差异与以前的研究相比，瑞典南部。接近范围限制（由气候因素控制）似乎是主要因素，造成一般较低的花粉生产，然而，个别类群以不同的方式作出反应，这取决于不同的生长行为，繁殖策略和物种和亚种，代表花粉类群。背景花粉成分以乔木类群为主，贡献率为c。占总花粉量的60%。禾本科占主导地位的本地组件。这里提出的PPE是迄今为止最合适的参数，用于量化的植被在苔原树线，但是，数据表明，谨慎需要行使与选择适当的PPE在其生态范围内的分类群的准确量化。
Successful reconstruction of vegetation from fossil pollen data in the arctic and alpine tundra, and at the forest—tundra ecotone, is hampered by low pollen production of the major taxa in these environments and the likely dominance of the background pollen component. New approaches to the quantification of vegetation from pollen data (the REVEALS and LOVE models) rely on quantification of background and local pollen by applying models of pollen dispersal and deposition to modern pollen— vegetation survey work. To date, research within this emerging area has focused on lowland environments. This paper presents pollen productivity estimates (PPEs) from the forest—tundra ecotone derived from west central Sweden, discusses the relevant source area of pollen (RSAP) in this environment and estimates the background pollen contribution. The results suggest that the RSAP for moss polsters at the forest—tundra ecotone is c. 500 m, and that PPEs for the major forest tundra ecotone taxa show significant differences compared with previous studies from southern Sweden. Proximity to range limits (controlled by climatic factors) appears to be the main factor causing generally lower pollen production; however, individual taxa respond in different ways, depending on differences in growth behaviour, reproductive strategy and the species and subspecies that represent the pollen taxa. The background pollen component was dominated by arboreal taxa, and contributed c. 60% of the total pollen loading. Graminoids dominated the local component. The PPEs presented here are to date the most appropriate parameters to use for quantification of vegetation at the tundra treeline; however, the data demonstrate that caution needs to be exercised with regards to selection of appropriate PPEs for accurate quantification of taxa at their ecological range.