Phytolith and Carbon Isotope Evidence for Late Quaternary Vegetation and Climate Change in the Southern Black Hills, South Dakota

Analyses of phytoliths and carbon isotopes document change in late Quaternary grasslands in the Red Valley of the southern Black Hills. Late Pleistocene grassland composition was equivalent to the C3grass parklands of modern central Alberta. The rise of mixed grassland occurred rapidly between 11,000 and 9000 yr B.P. Early Holocene mixed grasslands included both short and tall C4grasses. A mid-Holocene erosional unconformity (ca. 8000 to 4500 yr B.P.) precludes phytolith or isotope analysis, but suggests lack of vegetation and landscape denudation caused by a drier climatic. Basin-wide stability and soil development followed the erosional episode (ca. 4500 to 3600 yr B.P.). Mesic-adapted C4panicoid grasses increased during this period of soil development. Low-magnitude fluctuation in the C4-dominated mixed grassland occurred throughout the late Holocene (3600 yr B.P. to present). Rise in δ13C values during the last 1000 yr without corresponding change in phytoliths may indicate a decrease in woodlands caused by increased fire frequency.

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Late Holocene flood probabilities in the Black Hills, South Dakota with emphasis on the Medieval Climate Anomaly

CATENA ◽

10.1016/j.catena.2014.10.002 ◽

2015 ◽

Vol 130 ◽

pp. 62-68 ◽

Cited By ~ 9

Author(s):

Tessa M. Harden ◽

Jim E. O'Connor ◽

Daniel G. Driscoll

Keyword(s):

South Dakota ◽

Late Holocene ◽

Black Hills ◽

Medieval Climate Anomaly ◽

Climate Anomaly

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New evidence of mid- to late- Holocene vegetation and climate change from a Neolithic settlement in western fringe of Central Ganga Plain: Implications for Neolithic to Historic phases

The Holocene ◽

10.1177/0959683620972770 ◽

2020 ◽

pp. 095968362097277

Author(s):

Deepika Tripathi ◽

Bahadur Singh Kotlia ◽

Manish Tiwari ◽

Anil K Pokharia ◽

Shailesh Agrawal ◽

...

Keyword(s):

Late Holocene ◽

Isotope Analysis ◽

Cereal Crops ◽

Ganga Plain ◽

Ecological Strategies ◽

Humid Climate ◽

Religious Evolution ◽

New Evidence ◽

Gradual Transformation ◽

Vegetation And Climate

Here we present a continuous palaeoclimatic record of 5980 years (7230 cal BP–1250 cal BP) from Hetapatti, a Neolithic site situated on the western fringe of the Central Ganga Plain. The region was a center of reurbanisation following the decline of the Harappan civilisation and is considered a hub of economic, political and religious evolution since the sixth millennium BC. Hetapatti contains an uninterrupted sequence from Neolithic to Historic (Gupta) period. The study integrates two different approaches (phytoliths and carbon isotope analysis) to infer vegetational and climatic changes and to understand their relationship to the cultural sequence. Our results show a gradual transformation from a warm and humid climate into a warm and dry climate from the Neolithic to Historic (Gupta) period. We find an abrupt weakening of the ISM at ~2080 cal BP driving a warm and dry climate. The comparison of our data with other high resolution regional and global records led us to hypothesise a synchronicity in this warm and dry trend, coeval with the Roman warm period (RWP). The observed variation in vegetation and climate might have driven by the fluctuations in the Indian Summer Monsoon (ISM). Additionally, the phytolith analysis provides evidence of cereal crops including rice, wheat, barley, millets, etc. suggesting a crop affinity with the earlier Indus crop package. It is interesting to note that the site displays an uninterrupted cultural sequence from Neolithic to Historic times, with artefacts of each phase exhibiting technological and stylistic developments from the preceding culture. From this we infer that the well adapted socio-ecological strategies and availability of perennial rivers may have helped the ancient civilisation to absorb the stress relating to a varying climate.

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Time averaging and late Quaternary ecological replacement in Don’s Gooseberry Pit, South Dakota, USA

Quaternary Research ◽

10.1017/qua.2017.100 ◽

2017 ◽

Vol 89 (1) ◽

pp. 307-317 ◽

Cited By ~ 2

Author(s):

Melissa I. Pardi ◽

Russell W. Graham

Keyword(s):

South Dakota ◽

Great Plains ◽

Small Mammal ◽

Late Quaternary ◽

Black Hills ◽

Time Averaging ◽

Ecological Change ◽

Radiocarbon Dates ◽

Cold Adapted ◽

The North

AbstractLate Quaternary small mammal faunas document ecological change and biotic responses to past climates but are especially rare in some geographic regions such as the North American Great Plains. Don’s Gooseberry Pit (DGP), a cave in the southeastern Black Hills of South Dakota, USA, contains a fauna documenting small mammal community composition shifts and environmental change over the last 18,000 yr in this data-depauperate region. Although the stratigraphy of the cave appears to be primary, disparate radiocarbon dates indicate that there is mixing of the fauna throughout. A paleoenvironmental signal consistent with regional reconstructions still emerges from an analysis of the stratigraphically ordered fauna. Dated taxa from DGP record the ecological replacement of Dicrostonyx by Myodes and later Microtus in response to late Quaternary warming. Individually dated specimens of Dicrostonyx richardsoni confirm late survival of this cold-adapted taxon in the Black Hills (17,083 cal yr BP). Our results indicate that a coarse paleoecological signal is present in DGP, and that the Black Hills served as a “high-altitude” refugium for cold-adapted species following the end of the last glacial period.

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