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为了查明浙江省丽水市景宁畲族自治县分布的亚高山湿地群的成因及其环境意义,利用望东垟湿地钻孔沉积物样品,进行基于岩石学、年代学和孢粉学的综合研究,提取了研究区全新世以来较高分辨率环境演化信息。野外地貌地质调查表明,景宁亚高山湿地群的形成、分布与区域夷平面、古火山机构关系紧密。沉积物孢粉分析表明,研究区全新世植物种类丰富,主要由11大科属蕨类、8大科属裸子植物、20大科属阔叶类、10大科属陆生草本和7大科属水生沼生植物组成。利用孢粉组合带及气候代用指标,重建了古植被与古气候演化的6个阶段:1深度2.84~2.30 m,全新世早、中期温暖湿润气候,地带性植被为含针叶常绿、落叶阔叶林,非地带性植被为沼泽;2深度2.30~1.67 m,为全新世中、晚期温暖偏干气候,可见地带性植被为含针叶林常绿、落叶阔叶林,非地带性植被为草甸;3深度1.67~1.50 m,为全新世降温期温凉偏干气候,地带性植被为含常绿针阔叶混交林,非地带性植被为草甸向沼泽过渡;4深度1.50~1.22 m,为中世纪暖湿气候,地带性植被为落叶、常绿阔叶林,非地带性植被为沼泽;5深度1.22~1.02 m,为小冰期前期凉湿气候,地带性植被为含常绿针阔叶混交林,非地带性植被为沼泽;6深度1.02~0.50 m,为小冰期凉干与凉湿交替气候,地带性植被类型为含常绿针阔叶混交林,非地带性植被为草甸与沼泽交替。研究结果表明,全新世以来,区域地貌过程、气候变化和沉积作用共同塑造了景宁地区亚高山湿地群,温度、湿度变化分别对地带性植被、非地带性植被演化产生了显著影响。本研究不仅对亚高山湿地生态系统保护具有重要意义,而且为探索中国东部全新世以来气候变化与区域湿地沉积响应提供了重要资料。
In order to find out the genesis and environmental significance of the subalpine wetland distributed in Jingning Shezu Autonomous County, Lishui City, Zhejiang Province, a comprehensive study based on petrology, chronology and palynology was conducted by drilling sediment samples from the Wangdongtang wetland. Extracted the higher resolution environmental evolution information since the Holocene in the study area. Field geology geological survey shows that the formation and distribution of Jingning subalpine wetland are closely related to the regional plane and the ancient volcano. The pollen analysis of sediments shows that Holocene is rich in plant species in the study area, and is composed of 11 genera of ferns, 8 families of gymnosperms, 20 families of broad-leaved species, 10 families of terrestrial herbs and 7 families Is a composition of aquatic macrophytes. Using sporopollen assemblages and climatic proxies, the six stages of paleo-vegetation and palaeoclimate evolution were reconstructed: depth 1 of 2.84-2.30 m, warm and humid climate in early and middle Holocene, and zonal vegetation including conifer evergreen and deciduous The broadleaf forest and the non-zonal vegetation are swamps. The depth of 2.30 ~ 1.67 m is warm and dry climate in the middle and late Holocene. It can be seen that the zonal vegetation is coniferous forest evergreen, deciduous broad-leaved forest, non-zonal vegetation 3 are 1.67-1.50 m in depth, which is a warm and dry climate in the Holocene. The zonal vegetation is evergreen coniferous and broad-leaved mixed forest, and the non-zonal vegetation is the transition from meadow to swamp. 4 Depth 1.50 ~ 1.22 m, which is a warm and humid climate in the Middle Ages. The zonal vegetation is deciduous and evergreen broad-leaved forest, and the non-zonal vegetation is the swamp. The depth of 1.22-1.02 m is the pre-ecotone of the Little Ice Age, and the zonal vegetation is evergreen The coniferous and broad-leaved mixed forest and the non-zonal vegetation are marsh. The depth of 1.02-0.50 m is alternate climate of cool-drying and cool-wetting in the small ice age. The zonal vegetation type is mixed evergreen coniferous and broad-leaved forest, and the non-zonal vegetation is Meadow and swamp alternate. The results show that since the Holocene, the regional topography, climate change and sedimentation have jointly shaped the sub-alpine wetland in Jingning area. The changes of temperature and humidity have significant effects on the evolution of zonal vegetation and non-zonal vegetation. This study not only has important significance for ecosystem protection of subalpine wetlands, but also provides important information for exploring the response of climate change and regional wetland deposition since the Holocene in eastern China.