Estimating the Relevant Source Area of Pollen in the past cultural landscapes of southern Sweden - A forward modelling approach
Estimating the Relevant Source Area of Pollen in the past cultural landscapes of southern Sweden - A forward modelling approach
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DOI：
10.1016/j.revpalbo.2008.08.008
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发表时间：
2009-02-01
影响因子：
1.9
通讯作者：
Mazier, Florence
中科院分区：
文献类型：
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作者：
Hellman, Sofie;Gaillard, Marie-Jose;Mazier, Florence
本文估算了瑞典南部全新世中晚期假想景观中的相关花粉源面积(RSAP)，以探讨过去植被组成、开度和结构的变化对斑块大小和空间分布的可能影响。如果要使用Sugita的景观重建算法(LRA)在局部空间尺度上实现过去植被的定量重建，则必须估计过去小流域(沼泽或湖泊)的RSAP。在这项研究中，我们使用计算机模拟模型HUMPOL来应用正向模拟方法来估计过去的RSAP。景观设计基于结合了古植物学、考古学和历史数据以及该地区的地质和土壤特征而制作的过去的景观图。选择了四个以不同景观/土地用途为特征的时间窗口，即新石器时代早期、青铜时代晚期、维京时代和中世纪。我们发现，无论盆地的大小(湖泊或沼泽，半径25250米)，RSAP对斯堪岛假想的过去景观的估计在选定的时间段之间相差约600m至1200m。时间片之间RSAP差异的最可能解释是斑块大小和斑块在景观中的空间分布不同。小型盆地(半径25米和70米)的RSAP约为1200米至2300米，较大盆地(半径250米)的RSAP约为2000米至3000米。这些数值在以前使用模拟或经验数据获得的斯堪的纳维亚半岛南部现代和过去区域行动方案估计值的范围内。这些结果表明，考虑到该地区分类群组成和传统土地利用的环境类型，小型湖泊(25-250米半径)的RSAP一般在1200-3000米范围内。正演模拟方法被发现有助于评估过去不同时期植被/景观特征变化对RSAP的可能影响。此外，对使用正向和反向建模方法获得的RSAP估计进行比较，对于确定过去最可信的RSAP估计将是重要的。(C)2008爱思唯尔B.V.保留所有权利。
In this paper, we estimate the Relevant Source Area of Pollen (RSAP) in past hypothetical landscapes of the Middle and Late Holocene in southern Sweden, in order to explore the possible effects of past changes in vegetation composition, openness and structure in terms of patch size and spatial distribution. The RSAP of small basins (bogs or lakes) in the past has to be estimated if quantitative reconstruction of past vegetation at the local spatial scale is to be achieved using Sugita's Landscape Reconstruction Algorithm (LRA). In this study we apply a forward modelling approach to estimate past RSAP using the computer simulation model HUMPOL The landscape designs are based on past landscape maps produced using a combination of palaeobotanical, archaeological and historical data, and the area's geology and soil characteristics. Four time windows characterised by different landscape/land-use were selected, i.e. Early Neolithic, Late Bronze Age, Viking Age, and Middle Ages. We found that RSAP estimates for hypothetical past landscapes in Skane differ by ca. 600 m to 1200 m between the selected time periods, whatever the size of the basin (lake or bog, 25250 m radius). The most probable explanation for the differences in RSAP between time slices is variable patch size and spatial distribution of patches in the landscape. The RSAPs vary between ca. 1200 and 2300 m for small basins (25 m and 70 m radius), and between ca. 2000 and 3000 m for larger basins (250 m radius). These values are within the range of earlier estimates of modern and past RSAPs for southern Scandinavia obtained using simulated or empirical data. These results suggest that, given the type of setting of that region in terms of taxa composition and traditional land-use, the RSAP for small-size lakes (25-250 m radius) will generally be in the range ca. 1200-3000 m. The forward modelling approach is found to be useful to assess the possible effects on RSAP of changes in vegetation/landscape characteristics between different periods of the past. Moreover, comparison of RSAP estimates obtained using both the forward and backward modelling approaches will be important to identify the most credible RSAP estimates for the past. (c) 2008 Elsevier B.V. All rights reserved.