Mid-late Holocene Research Articles

Holocene climatic fluctuations in the Gujarat Alluvial Plains based on a multiproxy study of the Pariyaj Lake archive, western India

A sediment core from Pariyaj Lake, from the Vatrak River basin, located at the desert margin in the Gujarat Alluvial Plains of western India, was investigated in a multidisciplinary aspect. The goal was to reconstruct the palaeoclimate, palaeoenvironment and tectonic history and to understand the role these factors played in the geomorphological evolution of the area during the Holocene. Palaeoclimatic interpretations also shed light on the factors responsible for the rise and fall of the Harappan civilisation. The results obtained based on multiproxy studies show five climatic phases during the last 11,000yr BP. Phase 1 (~11,000calyr BP) represents a very humid climate and high precipitation/discharge leading to high lake stand as attested by the high pollen concentration of semi-evergreen tree taxa, phytoliths belonging to cool and moist grasses, and large proportion of algae, marking the onset of Holocene. In phase 2 (~8000 to 9000calyr BP) a significantly reduced yield of pollen, phytoliths and aquatic algae indicates shrinkage of the lake. Phase 3 (~7630calyr BP) shows moderate yield of pollen and phytolith pointing towards fluctuating precipitation conditions. Phase 4 (~5864 to 4680calyr BP) shows very low pollen and phytolith counts, indicating a very dry spell. Finally, phase 5 (~4680 to 3500calyr BP) shows a good density and diversity of flora. The wet climate and high lake stand ~11,000calyr BP, 7630calyr BP and after ~4680calyr BP are synchronous with the lacustrine, marine and aeolian records of western India. The contribution of winter precipitation at 7630calyr BP and after ~4680calyr BP can be correlated with similar records from Rajasthan Lake. Decrease in the precipitation activity, the low lake stand and the onset of dry climatic condition between 8000 and 9000calyr BP corresponds to a near global anomaly of this period. Another dry event between ~5864 and 4680calyr BP documented in Pariyaj Lake record is synchronous with various proxy records of the mid–late Holocene Afro-Asiatic monsoonal belt.

Holocene vegetation, environment and anthropogenic influence in the Fuzhou Basin, southeast China

A ∼40m sediment core (FZ4) was collected from the Fuzhou Basin, near the lower reaches of the Min River, in Fujian Province on the southeast coast of China. The sediment and pollen record contributes to our understanding of Holocene paleogeography, including local changes in vegetation and climate in the context of Neolithic cultural developments. The sediment record reveals a fluvial environment in the Fuzhou Basin during the late Pleistocene, and it demonstrates that a change from fluvial to estuarine conditions at ∼9000calyr BP resulted from postglacial sea level rise. Evidence of abundant marine diatoms and tidal flat laminations observed in the FZ4 sediments, implies that the Fuzhou Basin was under marine influence between ∼9000 and ∼2000calyr BP. After 2000calyr BP, a rapid retreat in coastline associated with fluvial aggradation and coastal progradation produced more shallow water for wetlands and initiated formation of the floodplain landscape. The pollen record reveals the presence of a dense subtropical forest between ca. 9000 and 7000calyr BP, representing the Holocene thermal maximum, which is linked with rising sea level and marine transgression in the Fuzhou Basin. Between ca. 5500 and 2000calyr BP, the thermophilous forest dominated by Castanopsis retreated and coniferous forest expanded, reflecting moderate climatic cooling during this period. Timing of the high frequencies for Pinus and ferns correspond with the mid-late Holocene cooling trend recorded in local mountain peatland and coastal regions of the lower Yangtze and Hanjiang deltas. Anthropogenically induced land cover change was negligible prior to the Tanshishan cultural period, which marks the beginning of Neolithic era sedentary village life on the Fujian coast around 5500 BP. The pollen transition at ca. 3000–1500calyr BP, distinguished by rising frequencies of Poaceae and taxa (including Cyperaceae and Artemisia) closely associated with agricultural land cover, indicates exploitation of newly formed lowlands in the emerging Min River floodplain. The historic era intensification of rice agriculture is reflected in this trend of rising frequencies of Poaceae. After ca. 2000calyr BP, we observe the onset of a marine regression followed by evidence for an intensely human-impacted environment characterized by sharp rises in pioneer plants such as Poaceae and Dicranopteris. This transition coincides with a rapid retreat of coastline and emergence of the Fuzhou Basin floodplain.

Stratigraphic architecture and evolution of a barrier seagrass bank in the mid-late Holocene, Shark Bay, Australia

Abstract Within the Faure Sill complex (Shark Bay, Western Australia), a combination of remote sensing analysis, seismic stratigraphy and cores to ground truth, together with radiocarbon dating, demonstrate the interconnection between sediment body morphologies, seagrass related substrates and pre-existing topography and reveal the system as a channel–bank complex. Sea level fluctuations appear to have largely controlled the hydrodynamic conditions of the bank, contributing to each stage of its evolution. 1) Not earlier than 8.5–8.0 ka BP, in a lowstand period, after an erosive event of underlying palaeosurfaces, seagrass establishment progressively contributed to initiating bank growth. 2) Around 6800 years BP, bank accumulation reached its apex, in conjunction with a rapid sea transgression. 3) During the Late Holocene, succeeding a slow decline to present sea level, bank growth continued to fill available accommodation space and a number of hiatuses, indicating temporal and spatial discontinuities within the process of bank building, are recognised. Average depositional rates of bank building (1.3 m/ka) conform to previous estimates derived for seagrass banks but rates are strongly facies dependent, attesting to the dynamic nature of this channel–bank complex. The extensive seagrass meadows are essential for a wide range of aspects of the environment of the Shark Bay area. Not only are they particularly important for the entire shallow benthic ecosystem, but they also had a major role in the partial closure of the southern basins and hence determining the development of hypersaline conditions and associated oolitic microbial and evaporitic facies in Hamelin Pool and L'Haridon Bight. Moreover, this system has a critical role in producing, sequestering and storing organic carbon.

Major mid-late Holocene cooling in the East China Sea revealed by an alkenone sea surface temperature record

Although the mid-late Holocene cold and dry event about 4000 years ago (the 4 ka event) has been observed almost globally, it was most prominent in terrestrial climate proxies from the lower latitudes. Here we evaluate the oceanic response to this event in terms of a Holocene sea surface temperature (SST) record reconstructed using the U 37 K′ index for Core B3 on the continental shelf of the East China Sea. The record reveals a large temperature drop of about 5°C from the mid-Holocene (24.7°C at 5.6 ka) to the 4 ka event (19.2°C at 3.8 ka). This mid-late Holocene cooling period in Core B3 correlated with (i) decreases in the East Asia summer monsoon intensity and (ii) the transition period with increased El Nino/Southern Oscillation activities in the Equatorial Pacific. Our SST record provides oceanic evidence for a more global nature of the mid-late Holocene climate change, which was most likely caused by a southward migration of the Intertropical Converge Zone in response to the decreasing summer solar insolation in the Northern Hemisphere. However, the large SST drop around Core B3 indicates that the mid-late Holocene cooling was regionally amplified by the initiation/strengthening of eddy circulation/cold front which caused upwelling and resulted in additional SST decrease. Upwelling during the mid-late Holocene also enhanced with surface productivity in the East China Sea as reflected by higher alkenone content around Core B3.

Sedimentological evidence for the Late Holocene sea level change at the Enjefa Beach exposures of Kuwait, NW Arabian Gulf

The mid-late Holocene drop in relative sea level has resulted in the deposition and progradation of coastal facies along the Enjefa Beach in Kuwait, NW Arabian Gulf. These coastal facies display various depositional subenvironments, including landward foreshore beach, tidal channel, shallow tidal channel, and coastal sand flat. The foreshore beach facies consist of dominantly planar laminated beds. Main tidal channel subenvironments are interpreted for the trough cross-bedded facies. The shallow tidal channel deposits are composed of variable oriented planar wedge-shaped and ripple cross-bedded facies. The coastal sand flat deposits consist of extensively burrowed beds with a large network of Ophiomorpha burrows. These exposures are overlain by the recent continental deposits of rubbles and artificial infill. The mere exposed occurrence of these rocks as well as the above facies stacking pattern reflects progradation as a result of relative drop in sea level. Based on the carbon dating of these sediments, the last phase of the relative sea level drop likely occurred around 1,800 years ago. Neotectonics of local structuring, due to the regional northeastward movement of the Arabian Plate under the Zagros Fold Belt, might have a role in this sea receding

Pollen-inferred Holocene vegetation and climate histories in Taro Co, southwestern Tibetan Plateau

A 310-cm-long sediment core, covering the last 10,200 years, was collected from Taro Co on the southwestern Tibetan Plateau and analyzed for pollen, grain size and total inorganic carbon content. The pollen data showed that vegetation changed from alpine steppe to alpine meadow during 10,200–8,900 cal a BP, to alpine steppe dominated by Artemisia during 8,900–7,400 cal a BP, to alpine meadow during 7,400–3,300 cal a BP and to alpine steppe after 3,300 cal a BP. Correspondingly, the pollen, grain size and total inorganic carbon content results revealed climatic change in this area over four stages. The initial stage was from 10,200 to 8,900 cal a BP, during which the climate changed from cold-dry to warm-humid. The second stage (8,900–7,400 cal a BP) was characterized by a warm and dry climate. However, at approximately 7,400 cal a BP, the climate began to become cold and humid, which continued until 3,300 cal a BP. The last stage, from 3,300 cal a BP to present, was characterized as cold and increasingly arid. Climatic events of the early and mid-late Holocene showed that the area was significantly affected by the westerlies. However, the mid-Holocene climate in Taro Co was controlled by the Indian monsoon. The mid-late Holocene depositional environment record of Taro Co was very important to further elaborate the degree of influence by the westerlies or Indian monsoon.

Holocene landscape dynamics at the tell Arslantepe, Malatya, Turkey – Soil erosion, buried soils and settlement layers, slope and river activity in a middle Euphrates catchment

Alluvial and colluvial sequences were studied around the prehistoric tell Arslantepe in 11 exposures and additional auger cores. The chronology is based on 11 optically stimulated luminescence (OSL) ages, four radiocarbon ages, and the embedded artifacts. Sediments contained wood charcoals, providing information on former vegetation. Fluvial activity is documented during Late Glacial times (15.4 ± 2.5, 12.8 ± 3.1 kyr) and frequently after Roman times. Slope and soil erosion occurred in the early (10.6 ± 1.4, 8.2 ± 0.7 kyr) and mid–late Holocene (6.7 ± 0.9, 5.4 ± 0.7–4.7 ± 0.7, 2.6 ± 0.2–2.5 ± 0.2, 1.9 ± 0.2–1.8 ± 0.2 kyr, and during the last 1000 years). The early Holocene erosion phases pre-date the so far established onset of settlement at the tell. This either indicates an earlier onset of agricultural land use than assumed or climatic influence on erosion, such as the 10.3 and 8.2 kyr climate events known from Western Europe. The erosion phases at around 5.0 and 2.6 kyr could reflect geomorphic responses to societal collapse (Late Chalcolithic state, Neo-Hittite kingdom) at Arslantepe. Most intensive Holocene soil erosion and landscape degradation occurred after occupation of the region by the Roman Empire. This is paralleled by the onset of river activity. A part of the lower neo-Hittite town as well as an early Holocene Terra Rossa–like soil that had formed rapidly were found buried. So far, no indication for mid–late Holocene fluvial activity of the adjacent creeks until Roman times has been found. Our results illustrate the large potential of slope deposits for long term reconstructions of human induced landscape transformation in Anatolia.

Pollen and phytolith evidence for rice cultivation and vegetation change during the mid-late Holocene at the Jiangli site, Suzhou, East China.

Pollen and phytolith analyses were undertaken at the Jiangli site in Suzhou, Jiangsu Province, combined with studies on macrofossils by flotation. The concentration of pollen decreased while the percentage of Poaceae pollen in the profile increased from the late phase of the Majiabang Culture to the Songze Culture suggesting that human impact on the local environment intensified gradually. The discovery of rice paddy implies a relatively advanced rice cultivation in this area during the middle-late Holocene. Other than phytoliths, the high percentage of Oryza-type Poaceae pollen (larger than 40 μm) supplied robust evidence for the existence of rice paddy. Moreover, the fact that the farther from the rice paddy, the lower the concentration and percentage of Poaceae pollen also proves that the dispersal and deposition of pollen is inversely proportional to the distance.

Mid-late Holocene lake levels and trophic states of a shallow lake from the southern Pampa plain, Argentina

Changes in trophic status of the shallow Lake La Brava (southeastern Pampa plain of Argentina) are evaluated based on geochemical, biological and sedimentological data. Based on a conceptual framework, we propose that the lake level defines the water column mixing conditions, affecting internal lake processes and determining the transparency of lake water. The shift between alternative states is reconstructed for the last ~4800 years. Four main lake stages have been recognized, although short term shifts characterize all stages. A turbid phytoplankton-dominated state prevailed between ~4700-4500 cal yr before present (BP). Drier conditions and low lake levels pushed the lake to a clear state until 2000 cal yr BP. Afterwards the lake switched back to a turbid state, and these conditions persisted until ~200 cal yr BP. In the last 200 years, the lake switched back and forth between clear and turbid states. The latter represents the modern conditions of the lake since ~1950 AD. These shifts can be attributed mainly to climatic drivers.

Holocene environmental change in Eastern Spain reconstructed through the multiproxy study of a pedo-sedimentary sequence from Les Alcusses (Valencia, Spain)

We present a multiproxy characterization of a complex, polycyclic soil sequence from Les Alcusses, Moixent (Valencia, SE Spain). The area has abundant settlements dating from early Neolithic to Roman times. The sequence comprises six main units, dating back to 8.7–8.5 ka cal BP. We integrated mineralogy, inorganic (pH, grain size, elemental composition) and organic chemistry (pyrolysis gas chromatography/mass spectrometry, pyrolysis–GC/MS), micro-charcoal, pollen and non-pollen palynomorph (NPP) data. All data is contextualized within a framework of archaeological information and radiocarbon dating, with the aim of deciphering the Holocene environmental changes.We infer a shift from wetter and warmer, in the early-mid Holocene, to drier and cooler climatic conditions with increased fire occurrence, in the mid-late Holocene (particularly after 5.3 ka cal BP). Although the pollen record indicates a rapid forest retreat and expansion of grasslands for the Neolithic period, local proxies (molecular soil OM indicators and NPP) point to the presence of pine forest in the studied location well after the regional decline started. The same proxies suggest a sharp forest decline after about 7.0 ka cal BP. Strong soil erosion, likely linked both to climatic instability and the intensification of human exploitation, resulted in a hiatus from the late Neolithic to the Roman period. A certain climate amelioration, wetter conditions and land abandonment or, at least, lower human pressure, are suggested for the late Roman period/Early Middle Ages. Direct evidence of changes in soil properties due to agriculture was not detected in the sequence except for the upper soil unit studied, which reflects intense agricultural management (with the possible use of agrochemicals).

A stable mid-late Holocene monsoon climate of the central Tibetan Plateau indicated by a pollen record

A 9500-year Holocene pollen record from a river valley wetland of the central Tibetan Plateau reveals the history of climate fluctuations. At the beginning of the Holocene, the catchment area of the study site was covered by sparse drought-tolerant herbaceous vegetation, suggesting a climate cooler and drier than today. This period was characterised by a high rate of soil erosion as indicated by the deposition of siliciclastic sediment at the site. The environment became wetter during the early mid-Holocene around 8060–7120 cal. BP, and during which a wetland habitat dominated by sedges was developed at the site. Throughout the mid-Holocene, the wetland remained stable, with steady accumulation of organic material. A change to a slightly drier condition took place in the late Holocene, and after about 1000 cal. BP, a marked increase in drought-tolerant herbs occurred. Although no trees lived around the site, the record shows low, but steady increasing, tree pollen frequencies throughout the mid-late Holocene. This result confirms a stable, largely monsoonal, climate in central Tibet over the middle to late Holocene. It also suggests that the optimum period of monsoonal precipitation in central Tibet occurred later and lasted longer than that in the East Asian Monsoon region.

Sediment fluxes and buffering in the post‐glacial Indus Basin

AbstractThe Indus drainage has experienced major variations in climate since the Last Glacial Maximum (LGM) that have affected the volumes and compositions of the sediment reaching the ocean since that time. We here present a comprehensive first‐order source‐to‐sink budget spanning the time since the LGM. We show that buffering of sediment in the floodplain accounts for ca. 20–25% of the mass flux. Sedimentation rates have varied greatly and must have been on average three times the recent, predamming rates. Much of the sediment was released by incision of fluvial terraces constructed behind landslide dams within the mountains, and especially along the major river valleys. New bedrock erosion is estimated to supply around 45% of the sedimentation. Around 50% of deposited sediment lies under the southern floodplains, with 50% offshore in large shelf clinoforms. Provenance indicators show a change of erosional focus during the Early Holocene, but no change in the Mid–Late Holocene because of further reworking from the floodplains. While suspended loads travel rapidly from source‐to‐sink, zircon grains in the bedload show travel times of 7–14 kyr. The largest lag times are anticipated in the Indus submarine fan where sedimentation lags erosion by at least 10 kyr.

Pollen and phytolith evidence for rice cultivation and vegetation change during the mid-late holocene at the Jiangli site, Suzhou, East China.

Pollen and phytolith analyses were undertaken at the Jiangli site in Suzhou, Jiangsu Province, combined with studies on macrofossils by flotation. The concentration of pollen decreased while the percentage of Poaceae pollen in the profile increased from the late phase of the Majiabang Culture to the Songze Culture suggesting that human impact on the local environment intensified gradually. The discovery of rice paddy implies a relatively advanced rice cultivation in this area during the middle-late Holocene. Other than phytoliths, the high percentage of Oryza-type Poaceae pollen (larger than 40 µm) supplied robust evidence for the existence of rice paddy. Moreover, the fact that the farther from the rice paddy, the lower the concentration and percentage of Poaceae pollen also proves that the dispersal and deposition of pollen is inversely proportional to the distance.

Rapid climatic changes and resilient vegetation during the Lateglacial and Holocene in a continental region of south-western Europe

Palynological, sedimentological and geochemical analyses performed on the Villarquemado paleolake sequence (987m a.s.l, 40°30′N; 1°18′W) reveal the vegetation dynamics and climate variability in continental Iberia over the last 13,500calyrBP. The Lateglacial and early Holocene periods are characterized by arid conditions with a stable landscape dominated by pinewoods and steppe until ca. 7780calyrBP, despite sedimentological evidence for large paleohydrological fluctuations in the paleolake. The most humid phase occurred between ca. 7780 and 5000calyrBP and was characterized by the maximum spread of mesophytes (e.g., Betula, Corylus, Quercus faginea type), the expansion of a mixed Mediterranean oak woodland with evergreen Quercus as dominant forest communities and more frequent higher lake level periods. The return of a dense pinewood synchronous with the depletion of mesophytes characterizes the mid-late Holocene transition (ca. 5000calyrBP) most likely as a consequence of an increasing aridity that coincides with the reappearance of a shallow, carbonate wetland environment. The paleohydrological and vegetation evolution shows similarities with other continental Mediterranean areas of Iberia and demonstrates a marked resilience of terrestrial vegetation and gradual responses to millennial-scale climate fluctuations. Human impact is negligible until the Ibero-Roman period (ca. 2500calyrBP) when a major deforestation occurred in the nearby pine forest. The last 1500years are characterized by increasing landscape management, mainly associated with grazing practices shaping the current landscape.

Holocene lake-level changes of Hurleg Lake on northeastern Qinghai-Tibetan Plateau and possible forcing mechanism

The palaeoshorelines of a lake are the direct geomorphic evidences to reflect past water levels and record information on palaeoclimatic changes. Previous research indicates that the timing and forcing mechanisms of climatic change on the northeastern Qinghai-Tibetan Plateau (NE QTP) are still controversial. Here, we report quartz optically stimulated luminescence (OSL) ages for beach deposits and accelerator mass spectrometry (AMS) 14C age for plant remains, shoreline features and geomorphic exposures that contribute to a reconstruction of the lake-level history of Hurleg Lake on the NE QTP. The results imply that (1) three high lake levels are dated to 6.8–6.4, 5.0–4.7 and 2.2–1.4 kyr, corresponding to relatively wet and stable climate from pollen records of sediment core in this lake during mid–late Holocene; (2) the highest lake-level period occurred at 5.0–4.7 kyr, which is almost synchronous with the highest effective moisture phase from synthesized lake records influenced by the Westerlies and (3) no beach deposits around Hurleg Lake and lower lacustrine deposits in Toson Lake were found during early Holocene, suggesting lower lake level of Hurleg Lake in this period. These results might imply that the Westerlies and local topography rather than Asian summer monsoon dominate the moisture availability in this region during the Holocene.

500-year climate cycles stacking of recent centennial warming documented in an East Asian pollen record

Here we presented a high-resolution 5350-year pollen record from a maar annually laminated lake in East Asia (EA). Pollen record reflected the dynamics of vertical vegetation zones and temperature change. Spectral analysis on pollen percentages/concentrations of Pinus and Quercus, and a temperature proxy, revealed ~500-year quasi-periodic cold-warm fluctuations during the past 5350 years. This ~500-year cyclic climate change occurred in EA during the mid-late Holocene and even the last 150 years dominated by anthropogenic forcing. It was almost in phase with a ~500-year periodic change in solar activity and Greenland temperature change, suggesting that ~500-year small variations in solar output played a prominent role in the mid-late Holocene climate dynamics in EA, linked to high latitude climate system. Its last warm phase might terminate in the next several decades to enter another ~250-year cool phase, and thus this future centennial cyclic temperature minimum could partially slow down man-made global warming.

Paleoambientes y Uso de los Recursos Leñosos por los Grupos Cazadorez-Recolectores del Noreste de Patagonia desde el Holoceno Medio

Environmental changes occurred during Mid-Late Holocene have had influence over the availability of resources and the Patagonian hunter-gatherer strategies on environment use. In this sense,

Holocene fire in Fennoscandia and Denmark

Natural disturbance dynamics, such as fire, have a fundamental control on forest composition and structure. Knowledge of fire history and the dominant drivers of fire are becoming increasingly important for conservation and management practice. Temporal and spatial variability in biomass burning is examined here using 170 charcoal and 15 fire scar records collated throughout Fennoscandia and Denmark. The changing fire regime is discussed in relation to local biogeographical controls, regional climatic change, anthropogenic land use and fire suppression. The region has experienced episodic variability in the dominant drivers of biomass burning throughout the Holocene, creating a frequently changing fire regime. Early Holocene biomass burning appears to be driven by fuel availability. Increased continentality during the mid-Holocene Thermal Maximum coincides with an increase in fire. The mid–late Holocene front-like spread of Picea abies (Norway spruce) and cooler, wetter climatic conditions reduce local biomass burning before the onset of intensified anthropogenic land use, and the late Holocene increase in anthropogenic activity created artificially high records of biomass burning that overshadowed the natural fire signal. An economic shift from extensive subsistence land use to agriculture and forestry as well as active fire suppression has reduced regional biomass burning. However, it is proposed that without anthropogenic fire suppression, the underlying natural fire signal would remain low because of the now widespread dominance of P. abies.

Magnetism of the Huguangyan Maar Lake sediments, Southeast China and its paleoenvironmental implications

The Huguangyan (HGY) lake, a typical maar lake in the southeast of China, is sensitive to the evolution of the Asian monsoon system, including the East Asian summer monsoon (EASM) and the Indian summer monsoon (ISM). So far, the mechanism of how magnetic properties of the HGY lake sediments respond to climate changes has not been well determined. In this study, we performed a detailed mineral-magnetic analysis on the high-resolution HGY sediments. Results revealed that finer-grained magnetite (superparamagnetic and single domain magnetite mixed with a small amount of goethite and hematite) is the dominant magnetic mineral, which is consistent with the magnetic properties of the red weathered soils collected from the catchments, but differs greatly from that of the aeolian inputs. Therefore, magnetic minerals of the HGY sediments were originated mainly from the lake catchment, rather than the wind-blown dust inputs. Considering the high tephra wall (relative elevation of 10–20m) and great precipitation, surface runoff by rainfall is interpreted as the main process to transport red soils into the lake. The magnetic records of HGY sediments revealed that the summer monsoon was enhanced at the early Holocene and then declined abruptly at the mid-late Holocene (~5.5kyr cal. BP). This pattern strongly mimics the evolution pattern of ISM, but is inconsistent with the EASM. Thus, we suggest that the magnetic records from HGY have the great potential to investigate the evolution of ISM.

Palaeovegetation and climate oscillation of western Odisha, India: A pollen data-based synthesis for the Mid-Late Holocene

The last 6000 years are of particular interest to the understanding of the Earth System because the boundary conditions of the climate system did not change dramatically (in comparison to larger glacial–interglacial changes), and because abundant, detailed regional palaeoclimatic proxy records cover this period. Here, we present fossil pollen data and examine their climatic interpretation based on a 200-cm-deep trenched sedimentary profile from Mahanadi river side, located near the Barpahar hillock of Bargarh District, Odisha, which is influenced by the South-west and North-east monsoon. The 5840 y chronology of the sediment core is based on three 14C dates on soil samples. During 5840–4380 BP, dense tropical mixed deciduous forest consisting of Madhuca, Syzygium and Acacia flourished in the region along with Rhizophora under a warm and humid climate governed by high monsoonal activity. This phase of climate is associated with the Holocene Climatic Optimum which falls within the temporal range of 8000–5000 BP. Subsequently, an increase in humidity was discerned between 4380 and 3230 BP, as evident by increase in forest elements, under warm and relatively humid climate in response to an increased monsoon. The climate during 3230–1860 BP was mild and in general less humid than today. This climate event was inevitably influenced by a notable global cold event 4200 years ago, which is synchronous with the collapse of the world's first human empire in Mesopotamia. After this event, there was a return of more humid climate from 1860 to 1300 BP, marked by high values of Potamogeton, Myriophyllum, Nymphoides, and fungal and trilete fern spores. This is further supported by the presence of Rhizophora and Sonneratia indicating high precipitation under the influence of coastal habitation. A striking signal of the Little Ice age (LIA) was observed since 1300 BP when the climate became relatively dry, as recognized in a sudden decline in major arboreals, along with high frequency of occurrence of dry herbs. This changing pattern of humidity was also reflected in the proportions of marshy/aquatic taxa, as well as ruderal taxa which is a result of human impact. The study will be helpful to display the palaeovegetation and climate in the region between Bengal and the Ganga plain.