| 引用本文: | 侯桂林,曹艳敏,田文龙,潘登,申声曼,陈旭.近400年来湖北大九湖泥炭地摇蚊对湿度变化的响应.湖泊科学,2022,34(3):1030-1042. DOI:10.18307/2022.0326 |
| Hou Guilin,Cao Yanmin,Tian Wenlong,Pan Deng,Shen Shengman,Chen Xu.Response of chironomid assemblages to the changes of wetness in Dajiuhu Peatland of Hubei Province during the past 400 years. J. Lake Sci.2022,34(3):1030-1042. DOI:10.18307/2022.0326 |
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| 摘要: |
| 神农架大九湖泥炭地是华中地区少有的亚高山泥炭藓湿地，是研究长江中游气候变化及其生态效应的理想区域.本文通过大九湖一根泥炭岩芯的年代学、元素及摇蚊亚化石记录，结合区域古气候资料，探讨大九湖泥炭地地表干湿变化历史及生物响应过程.结果表明，近400年来大九湖泥炭地古水文和摇蚊种群变化经历了3个主要阶段：1820s之前研究区内气候偏冷湿，尤其是1720s-1820s年间，冷湿的环境有利于泥炭中碳的大量积累，较高的地表有效湿度使得摇蚊大量生长，同时湖泊相摇蚊属种丰富度及含量均较高；1820s-1940s年间，区域内夏季降水量显著降低，同时伴随明显的区域增温过程，泥炭地地表有效湿度过低不利于水生生物生长，摇蚊种群生物量极低；1940s （尤其1970s）后，摇蚊种群丰度逐渐回升，但湖泊相摇蚊丰度较1820s以前明显降低，半陆生摇蚊属种丰度有所增加，说明尽管该时期泥炭地表湿度有所增加，但较1820s前仍较低，暖湿气候下泥炭分解也较为明显.本研究探索性地分析了气候变化背景下泥炭地摇蚊种群对泥炭地湿度变化的响应过程，这不仅为摇蚊亚化石在气候变化研究中的应用开拓了新的领域，同时也为全面、精准地理解泥炭地演化及区域环境变化过程提供了新线索. |
| 关键词: 摇蚊亚化石|地表湿度|泥炭地|大九湖 |
| DOI：10.18307/2022.0326 |
| 分类号: |
| 基金项目:国家自然科学基金项目（41877428）和流域关键带演化湖北省重点实验室开放基金项目（2021F01）联合资助. |
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| Response of chironomid assemblages to the changes of wetness in Dajiuhu Peatland of Hubei Province during the past 400 years |
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Hou Guilin1, Cao Yanmin1,2, Tian Wenlong1, Pan Deng1, Shen Shengman1, Chen Xu2
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1.Key Laboratory of Resources Conversion and Pollution Control of the State Ethnic Affairs Commission, College of Resources and Environmental Science, South-central Minzu University, Wuhan 430074, P. R. China;2.Hubei Key Laboratory of Critical Zone Evolution, China University of Geosciences, Wuhan 430074, P. R. China
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| Abstract: |
| Dajiuhu Peatland in Shennongjia forestry region is a rare subalpine Sphagnum wetland in central China. It is regarded as an ideal site to study climate change and ecological effects in the middle reach of the Yangtze River. Based on the records of geochronology, elements and subfossil chironomids of a peat core collected from Dajiuhu Peatland, combined with regional paleoclimate data, this paper aims to explore past changes in surface wetness and biotic response in Dajiuhu Peatland. Our results showed that three major stages were identified based on paleohydrology and chironomid assemblages in Dajiuhu Peatland during the past 400 years. Before the 1820s, especially between the 1720s and the 1820s, a cold and wet climate favored carbon accumulation in the peatland, and a high surface moisture promoted the growth of chironomids. Correspondently, limnic chironomid taxa were abundant and diverse during this period. Between the 1820s and the 1940s, a drop in summer precipitation, accompanying with evident regional climate warming, led to obvious drought and low surface humidity in the peatland, and hence rare aquatic midges and extremely low density of subfossil chironomid head capsules were found in sediments. Chironomid biomass and semi-terrestrial taxa then rebounded after the 1940s (especially after the 1970s), while the abundance of limnic taxa remarkably declined. This suggested that peatland surface wetness was still lower than that in the period before the 1820s, despite of a relatively increase in comparison with the previous stage (1820s-1940s). Warm and humid climate likely accelerated carbon decomposition in this period. This study explored the response of chironomid assemblages to surface wetness in peatland in the context of climate change, which not only launched a new field for the application of subfossil chironomids as a biotic proxy in climate change studies, but also provided new clues for tracking comprehensive and accurate information on peatland development and regional environmental change. |
| Key words: Subfossil chironomids|surface wetness|peatland|Dajiuhu |
