A long record of environmental change from bat guano deposits in Makangit Cave, Palawan, Philippines
A long record of environmental change from bat guano deposits in Makangit Cave, Palawan, Philippines
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DOI：
10.1017/s1755691007000059
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发表时间：
2007-01-01
影响因子：
1.2
通讯作者：
Stephens, W. Edryd
中科院分区：
文献类型：
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作者：
Bird, Michael I.;Boobyer, Ella M.;Stephens, W. Edryd
我们提出了第一个记录的全新世和更新世环境变化来自热带洞穴鸟粪序列的化学和稳定同位素组成的北方巴拉望（菲律宾）Makangit洞。180厘米的鸟粪序列主要来自食虫蝙蝠和鸟类，由两个不同的单位组成。上半部分的红褐色的氧化鸟粪沉积到110厘米，自中全新世以来，而下半部分的黑色，减少鸟粪沉积通过末次盛冰期（LGM）到> 30 000 BP。在末次盛冰期沉积的鸟粪中的碳同位素（VC）值高达千分之-13.5，表明当时洞穴周围存在以C-4为主的草原。鸟粪三角洲的C-13值为千分之-25到千分之-28，表明这种开放的植被在全新世中期被C-3为主的封闭热带森林所取代，与现在的森林相似。结果表明，北方巴拉望的气候在末次盛冰期比现在干燥得多。
We present the first record of Holocene and Pleistocene environmental change derived from the chemical and stable-isotope composition of a tropical cave guano sequence from Makangit Cave in northern Palawan (Philippines). The 180 cm sequence of guano, derived predominantly from insectivorous bats and birds, consists of two distinct units. An upper section of reddish-brown oxidised guano to 110 cm was deposited since the mid-Holocene while a lower section of black, reduced guano was deposited through the Last Glacial Maximum (LGM) to > 30 000 BP. Carbon-isotope (VC) values in guano deposited during the LGM bare as high as -13.5 parts per thousand indicating that a C-4-dominated grassland existed in the area around the cave at this time. Guano delta C-13 values of -25 parts per thousand to -28 parts per thousand suggest that this open vegetation was replaced by C-3-dominated closed tropical forest, similar to that of the present, by the mid-Holocene. The results suggest that the climate of northern Palawan was substantially drier at the LGM than is currently the case.