Fig 1.
Examples of coastal change foci of attention to which palaeo-data can make significant contributions in the context of modelling human and landscape responses to future sea level rise projections under emissions scenarios SSP5–8.5 and SSP2–4.5.
Highlighted time windows represent periods of focus herein; arrows indicate wider applicability of datasets.
Fig 2.
Well-preserved corrosion notches in Tràng An, such as these in the Tam Coc-Dich Dong part of the property, reveal separate phases of sea level stability during the Mid-Holocene marine transgression (8000–4000 cal. BP).
Notch locations and elevation data were recorded using either a Leica GS15 nRTK (network Real Time Kinematic) GNSS (Global Navigation Satellite System) receiver, and Leica TS06 total station, and later (in 2022) also a Leica BLK360 imaging laser (see inset). (Main photo: Ryan Rabett, inset photo: Thorsten Kahlert).
Fig 3.
SSP5–8.5 (low confidence) sea level rise models for the years 2050, 2100 and 2150, contrasted with published early to Middle Holocene coastline models.
The Tràng An Landscape Complex World Heritage Site is highlighted. All SSP models were generated by Thorsten Kahlert exclusively for this paper using Climate Central’s re-worked Shuttle Radar Topography Mapping Digital Surface Model (CoastalDEM® courtesy of Climate Central https://go.climatecentral.org/coastaldem/). Projected sea levels were obtained via the NASA IPCC AR6 Sea Level Projection Tool (https://sealevel.nasa.gov/data_tools/17) (Image: Thorsten Kahlert).
Fig 4.
SSP5–8.5 (med. confidence) sea level rise models contrasted with Mid-Holocene coastlines.
CoastalDEM® courtesy of Climate Central (https://go.climatecentral.org/coastaldem/). Projected sea levels were obtained via the NASA IPCC AR6 Sea Level Projection Tool (https://sealevel.nasa.gov/data_tools/17) (Image: Thorsten Kahlert).
Fig 5.
SSP2–4.5 (med. confidence) sea level rise models contrasted with Mid- to Late Holocene coastlines.
CoastalDEM® courtesy of Climate Central (https://go.climatecentral.org/coastaldem/). Projected sea levels were obtained via the NASA IPCC AR6 Sea Level Projection Tool (https://sealevel.nasa.gov/data_tools/17) (Image: Thorsten Kahlert).
Fig 6.
The Tràng An massif showing reconstructed min./max. elevation estimates for the local Mid-Holocene coastline [100] and projected SSP5–8.5 (low) SSP5–8.5 (med.) and SSP2–4.5 (med.) scenarios for the year 2150 (topographical base map derived from SRTM 1 Arc Sec DEM, courtesy of USGS / NASA: https://doi.org/10.5066/F71835S6).
(Image: Thorsten Kahlert).
Fig 7.
The Vung Tham doline in the centre of the Tràng An massif (2017).
The white ‘V’ in the centre of the frame denotes the location of the coring site (105.89745°E, 20.25281°N) (Photo: Thorsten Kahlert).
Table 1.
Mammalian genera (≥ 2 kg) identified from archaeological investigations in Tràng An by the SUNDASIA project compared to those recorded in the same landscape today and their major ecological role(s) with associated references.
Fig 8.
Vegetation cover on the Tràng An limestone massif.
Palaeoenvironmental evidence from Tràng An indicates that broad habitat conditions found on the massif today extend back to at least the Late Pleistocene (Photo: Ryan Rabett).
Fig 9.
Potential candidates for refaunation in the Tràng An Landscape Complex World Heritage Site.
Photo credits (left-right): Large-antlered muntjac (Muntiacus vuquangensis) (@Association Anoulak); Water deer (Hydropotes inermis) (Seong-Won Cho); Delacour’s langur (Trachypithecus delacouri) (Ryan Rabett).
Table 2.
Potential candidates for refaunation in the Tràng An Landscape Complex World Heritage Site.
References pertaining to the large-antlered muntjac (Muntiacus vuquangensis) are extrapolated from congeneric data but are as yet unconfirmed for this species.
Fig 10.
Monitoring visit to the Delacour’s langur trial reintroduction site on Ngoc Island, Tràng An (2022).
The release cage was used for initial climatization purposes and continues to serve as contact location between the free-ranging primates and monitoring staff (Photo: Ryan Rabett).