M. F. Quamar, Ashutosh Kumar Singh, L. Joshi, B. Kotlia, D. Singh, C. Simion, Tiberiu Sava, Nagendra Prasad
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Broad-leaved taxa during this phase show increased values considerably, indicating amelioration in climatic condition, which could be, in global perspective, broadly falling within the time-interval of the Holocene Climate Optimum (HCO; 7000–4000 BP). Between ~7216 and 6526 cal yr BP, dense conifers-dominated mixed broad-leaved forests transformed the conifers-dominated broad-leaved forests around the study area under a cold and drier climate with further reduction in monsoon precipitation. Subsequently, between ~6526 and 5987 cal yr BP, conifers-dominated broad-leaved forests continued to grow, but with lesser frequencies, around the study area under a comparatively less cold and dry climate with reduced monsoon precipitation. Finally, between ~5987 and 5817 cal yr BP, the frequencies of conifers-dominated broad-leaved forests further decreased around the landscape of the study area under a comparatively lesser cold and dry climate, probably indicating decreased monsoonal precipitation. Hence, the present study mainly showed the dominance of conifers forests around the study area between ~7522 and 7216 cal yr BP, ~7216 and 6526 cal yr BP, ~6526 and 5987 cal yr BP and between ~5987 and 5817 cal yr BP; however, broad-leaved forests also demonstrated increasing tendency between ~7522 and 7216 cal yr BP in the milieu of cold and dry climates. Moreover, the study also revealed that a lake was formed around 7522 cal yr BP along the Kulur River, a tributary of Saryu River around the study area and existed until 5817 cal yr BP.","PeriodicalId":54131,"journal":{"name":"Quaternary","volume":null,"pages":null},"PeriodicalIF":2.3000,"publicationDate":"2023-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Vegetation Dynamics and Hydro-Climatic Changes during the Middle Holocene from the Central Himalaya, India\",\"authors\":\"M. F. Quamar, Ashutosh Kumar Singh, L. Joshi, B. Kotlia, D. Singh, C. Simion, Tiberiu Sava, Nagendra Prasad\",\"doi\":\"10.3390/quat6010011\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"Understanding the spatiotemporal monsoonal variability during the Holocene helps in understanding the rise and fall of many civilizations. 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Subsequently, between ~6526 and 5987 cal yr BP, conifers-dominated broad-leaved forests continued to grow, but with lesser frequencies, around the study area under a comparatively less cold and dry climate with reduced monsoon precipitation. Finally, between ~5987 and 5817 cal yr BP, the frequencies of conifers-dominated broad-leaved forests further decreased around the landscape of the study area under a comparatively lesser cold and dry climate, probably indicating decreased monsoonal precipitation. Hence, the present study mainly showed the dominance of conifers forests around the study area between ~7522 and 7216 cal yr BP, ~7216 and 6526 cal yr BP, ~6526 and 5987 cal yr BP and between ~5987 and 5817 cal yr BP; however, broad-leaved forests also demonstrated increasing tendency between ~7522 and 7216 cal yr BP in the milieu of cold and dry climates. 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引用次数: 0
摘要
了解全新世的时空季风变化有助于理解许多文明的兴衰。本文对印度北阿坎德邦Kumaun小喜马拉雅地区2.65 m高的古湖泊沉积剖面进行了花粉分析,重建了中全新世季风降水的变化。研究表明,在~7522 ~ 7216 cal yr BP期间,研究区景观周围以针叶林为主的混交林,气候偏冷干燥,季风降水减少。在这一阶段,阔叶分类群的数值显著增加,表明气候条件有所改善,在全球范围内,这可能大致落在全新世气候最适期(HCO)的时间区间内;7000 - 4000个基点)。在~7216 ~ 6526 cal yr BP之间,随着季风降水的进一步减少,研究区以针叶林为主的阔叶林向针叶林为主的阔叶林转变。随后,在~6526 ~ 5987 cal yr BP期间,研究区周围寒干气候相对较少,季风降水减少,针叶林为主的阔叶林继续生长,但频率较低。最后,在~5987 ~ 5817 cal yr BP期间,在相对较少的寒冷和干燥气候下,研究区景观周围针叶林为主的阔叶林频率进一步减少,可能表明季风降水减少。因此,在~7522 ~7216 cal yr BP、~7216 ~6526 cal yr BP、~6526 ~5987 cal yr BP、~5987 ~ 5817 cal yr BP之间,研究区主要以针叶林为主;在~7522 ~ 7216 cal yr BP之间,阔叶林在干冷气候环境中也表现出增加的趋势。此外,研究还发现,沿沙留河的支流库鲁尔河在7522 calyr BP左右形成了一个湖泊,并一直存在到5817 calyr BP。
Vegetation Dynamics and Hydro-Climatic Changes during the Middle Holocene from the Central Himalaya, India
Understanding the spatiotemporal monsoonal variability during the Holocene helps in understanding the rise and fall of many civilizations. In this study, a 2.65 m high palaeo lake sedimentary profile from the Kumaun Lesser Himalaya, Uttarakhand State, India was pollen analysed to reconstruct the variability in the monsoonal precipitation during the Middle Holocene. The study revealed that between ~7522 and 7216 cal yr BP, conifers dominated mixed broad-leaved forests occurred around the landscape of the study area, indicating a less cold and dry climate with decreased monsoon precipitation. Broad-leaved taxa during this phase show increased values considerably, indicating amelioration in climatic condition, which could be, in global perspective, broadly falling within the time-interval of the Holocene Climate Optimum (HCO; 7000–4000 BP). Between ~7216 and 6526 cal yr BP, dense conifers-dominated mixed broad-leaved forests transformed the conifers-dominated broad-leaved forests around the study area under a cold and drier climate with further reduction in monsoon precipitation. Subsequently, between ~6526 and 5987 cal yr BP, conifers-dominated broad-leaved forests continued to grow, but with lesser frequencies, around the study area under a comparatively less cold and dry climate with reduced monsoon precipitation. Finally, between ~5987 and 5817 cal yr BP, the frequencies of conifers-dominated broad-leaved forests further decreased around the landscape of the study area under a comparatively lesser cold and dry climate, probably indicating decreased monsoonal precipitation. Hence, the present study mainly showed the dominance of conifers forests around the study area between ~7522 and 7216 cal yr BP, ~7216 and 6526 cal yr BP, ~6526 and 5987 cal yr BP and between ~5987 and 5817 cal yr BP; however, broad-leaved forests also demonstrated increasing tendency between ~7522 and 7216 cal yr BP in the milieu of cold and dry climates. Moreover, the study also revealed that a lake was formed around 7522 cal yr BP along the Kulur River, a tributary of Saryu River around the study area and existed until 5817 cal yr BP.