Pollen, vegetation change and climate at Lake Barombi Mbo (Cameroon) during the last ca. 33 000 cal yr BP: a numerical approach
Pollen, vegetation change and climate at Lake Barombi Mbo (Cameroon) during the last ca. 33 000 cal yr BP: a numerical approach
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过去约 10 年巴龙比姆博湖（喀麦隆）的花粉、植被变化和气候。
DOI：
10.5194/cp-8-59-2012
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发表时间：
2012
影响因子：
4.3
通讯作者：
J. Maley
中科院分区：
文献类型：
--
作者：
J. Lebamba;A. Vincens;J. Maley
本文对喀麦隆西南部BarombiMbo湖（4°39'45.75”N，9°23'51.63”E，303 m a.s.l.）在过去的33000 cal yr BP，改善以前的经验解释。生物化方法被应用于重建潜在的生物群落和森林演替阶段。平均年降水量，平均年潜在蒸散量和水分可用性指数重建使用现代模拟和人工神经网络技术。结果表明，在最潮湿的阶段（最高的降水量和最低的蒸散量）的混合万年青/半落叶型的Barombi Mbo湖周围茂密的森林环境，但从约有一个更明显的半落叶型。6500 cal yr BP至今，与季节性增加有关。这片森林显示出一个成熟的性格，直到约。2800 cal yr BP，然后在上个千年成为第二类型，可能是由于人类活动的增加。森林破碎化的两个事件，这是同步的最低重建降水量和最高的潜在蒸散值。第一个发生在LGM期间，第二个发生在CA。3000人左右。1200 cal yr BP，主要与高降水季节性有关。然而，稀树草原在Barombi Mbo盆地内从未广泛存在，而是以稀树草原斑块的形式存在于森林内。Barombi Mbo湖的气候重建表明，人工神经网络技术在该地区将更加可靠，尽管整个序列的年降水量值可能被低估。
This paper presents quantitative reconstructions of vegetation and climate along the pollen sequence of Lake Barombi Mbo, southwestern Cameroon (4°39'45.75" N, 9°23'51.63" E, 303 m a.s.l.) during the last 33 000 cal yr BP, improving previous empirical interpretations. The biomisation method was applied to reconstruct potential biomes and forest successional stages. Mean annual precipitation, mean annual potential evapotranspiration and an index of moisture availability were reconstructed using modern analogues and an artificial neural network technique. The results show a dense forested environment around Lake Barombi Mbo of mixed evergreen/semi-deciduous type during the most humid phases (highest precipitation and lowest evapotranspiration), but with a more pronounced semi-deciduous type from ca. 6500 cal yr BP to the present day, related to increased seasonality. This forest displays a mature character until ca. 2800 cal yr BP, then becomes of secondary type during the last millennium, probably due to increased human activity. Two episodes of forest fragmentation are shown, which are synchronous with the lowest reconstructed precipitation and highest potential evapotranspiration values. The first of these occurs during the LGM, and the second one from ca. 3000 to ca. 1200 cal yr BP, mainly linked to high precipitation seasonality. Savanna were, however, never extensive within the Barombi Mbo basin, existing instead inside the forest in form of savanna patches. The climate reconstructions at Lake Barombi Mbo suggest that the artificial neural networks technique would be more reliable in this region, although the annual precipitation values are likely under-estimated through the whole sequence.
喀麦隆南部（中非）的季节性变化和第三个千年 BP 雨林危机
影响因子：
2.3
作者：
Ngomanda;K. Neumann;A. Schweizer ;J. Maley
通讯作者：
J. Maley