Constraining pollen-based estimates of forest cover in the Amazon: A simulation approach
Constraining pollen-based estimates of forest cover in the Amazon: A simulation approach
复制标题
限制基于花粉的亚马逊森林覆盖估计：一种模拟方法
DOI：
10.1177/0959683618810394
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发表时间：
2018
期刊：
影响因子：
--
通讯作者：
M. Bunting
中科院分区：
文献类型：
--
作者：
B. Whitney;T. Smallman;E. Mitchard;J. Carson;F. Mayle;M. Bunting
花粉传播和沉积（PDD）模型有助于重建温带地区的历史植被，但其应用在热带地区受到限制，因为过去土地覆盖变化的不确定性最大。在这里，我们将 PDD 建模应用于亚马逊稀树草原和森林生态系统。使用来自亚马逊流域西南部湖泊的经验花粉数据来校准森林和非森林两部分景观的 PDD 模型。然后使用 PDD 模型模拟不同景观布置组合的花粉组合（多场景方法），反映全新世晚期可能的人为和气候驱动的森林覆盖变化。我们表明，亚马逊大型湖泊的花粉记录对森林损失的敏感性差异很大，具体取决于基线森林覆盖率。森林覆盖率超过 80% 的景观中的湖泊将检测到小幅减少（占总覆盖率的 5%），但这种敏感性会随着森林覆盖率的丧失而迅速降低。从马赛克和生态景观重建花粉存在广泛的不确定性。在森林-稀树草原马赛克中，通过花粉记录可能无法检测到森林覆盖率的大幅减少。在生态景观中，森林覆盖率与其在花粉记录中的表现之间的关系随着距森林边界距离的增加而迅速减弱。 PDD模型与多情景方法相结合的进一步应用可以解决热带地区过去土地覆盖基于花粉重建的不确定性，但需要进一步的投资和开发。
Pollen dispersal and deposition (PDD) modelling has been instrumental in reconstructing historical vegetation in temperate regions, but its application has been limited in the tropics where there is greatest uncertainty in past land cover change. Here, we apply PDD modelling to Amazonian savanna and forested ecosystems. Empirical pollen data from lakes situated in southwestern Amazonia were used to calibrate the PDD model for a two-component landscape of forest and non-forest. The PDD model was then used to simulate pollen assemblages for different combinations of landscape arrangements (the multiple scenario approach) that reflect possible anthropogenic and climate-driven forest cover change in the late-Holocene. We show that pollen records from large Amazonian lakes vary greatly in their sensitivity to forest loss depending on the baseline forest cover. Lakes in landscapes containing >80% forest will detect small reductions (5% of total cover), but this sensitivity degrades rapidly with forest cover loss. There are a wide range of uncertainties in pollen reconstructions from mosaic and ecotonal landscapes. In forest-savanna mosaics, large reductions of forest cover could be undetectable through the pollen record. In ecotonal landscapes, the relationship between forest cover and its representation in the pollen record rapidly weakens with increasing distance from the forest boundary. Further application of PDD modelling in combination with the multiple scenario approach can address the uncertainties in pollen-based reconstructions of past land cover in the tropics, but require further investment and development.
影响因子：
11.6
作者：
Anna-Kari Trondman;M. Gaillard;F. Mazier;S. Sugita;R. Fyfe;A. Nielsen;C. Twiddle;P. Barratt
通讯作者：
Anna-Kari Trondman;M. Gaillard;F. Mazier;S. Sugita;R. Fyfe;A. Nielsen;C. Twiddle;P. Barratt
影响因子：
4.3
作者：
Gaillard, M. -J.;Sugita, S.;Seppa, H.
通讯作者：
Seppa, H.