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Sunda Shelf

The Sunda Shelf is a vast continental shelf in Southeast Asia, representing a southward extension of the Asian mainland and forming the shallow seabed of the Java Sea, parts of the South China Sea, and surrounding waters, with an area of approximately 1.8 million km².^[1] It is the Earth's largest tropical shelf, encompassing the region between Vietnam and the Indonesian archipelago, bounded by the shelf edge along Sumatra, Java, Borneo, and the Malay Peninsula.^[2] Water depths over the shelf average around 50 meters, with extensive areas shallower than 20 meters, creating a stable platform that has remained tectonically quiescent since the Pliocene.^[1] During Pleistocene glacial-interglacial cycles, particularly since submersion-exposure cycles initiated around 400,000 years ago, the shelf was repeatedly exposed as the landmass known as Sundaland when sea levels dropped by up to 120 meters, connecting major islands such as Borneo, Sumatra, and Java into a contiguous area of about 2.5 million km² at the Last Glacial Maximum.^[3]^[4] This paleogeographic dynamism facilitated biogeographic dispersal of species, including early hominins like Homo erectus, and shaped regional river systems such as the Siam, North Sunda, and East Sunda palaeodrainages.^[2]^[3] Today, the shelf supports diverse ecosystems, including extensive mangrove forests and peatlands covering over 177,000 km², which store approximately 57 gigatons of carbon and have influenced Holocene atmospheric CO₂ levels by sequestering up to 107 gigatons.^[1] It also holds significant natural resources, such as natural gas reserves, and plays a key role in regulating global carbon-climate dynamics through enhanced weathering and as a potential "glacial lung" during exposure phases.^[2]

Geography and Geology

Location and Extent

The Sunda Shelf is a southeastern extension of the continental shelf of mainland Southeast Asia, encompassing the region from the Malay Peninsula southward through the southern South China Sea, the Java Sea, and the Karimata Strait, thereby linking the major islands of Sumatra, Java, Borneo, and Bali, along with numerous smaller surrounding islands.^[5]^[6] This vast submerged platform forms a key part of the maritime geography of Southeast Asia, underlying shallow seas that connect the Indochinese Peninsula with the Greater Sunda Islands.^[7] Covering an area of approximately 1.85 million km², the Sunda Shelf ranks as one of the largest continental shelves worldwide, second only to the Siberian Shelf in extent.^[8]^[5] Its boundaries are defined by the northern limit near the Gulf of Thailand, the southern edge at the Sunda Strait, the eastern boundary approaching the Makassar Strait, and the western limit off the coast of Sumatra and the Malay Peninsula.^[6]^[7] These margins delineate a stable epicontinental region situated atop the Sunda Plate.^[6] Bathymetrically, the shelf features exceptionally shallow waters, with depths rarely exceeding 50 meters and extensive areas shallower than 20 meters, contributing to its status as one of the world's shallowest continental shelves.^[7] The average slope is extremely gentle, often less than 1°, which facilitates the accumulation of thick sedimentary layers.^[7]^[1] The seafloor is predominantly composed of terrigenous sediments derived from major river deltas, such as those of the Mekong and Rajang rivers, forming siliciclastic deposits rich in quartz sands, silts, and clays.^[7]

Geological Formation and Tectonics

The Sunda Shelf formed primarily through Cenozoic tectonic processes involving the accretion of continental fragments to the stable Sundaland core, a region assembled from Gondwana-derived terranes during the Mesozoic and further shaped by interactions between the Indo-Australian, Eurasian, and Pacific plates.^[9] Subduction along the Sunda Trench, where the Indo-Australian Plate subducts beneath the Eurasian Plate at rates of approximately 4-7 cm/year, initiated around 45 Ma and drove the development of the Sunda Arc, a volcanic chain extending from Sumatra to Java with associated igneous activity.^[10] This subduction, combined with regional extension and compression, facilitated the formation of back-arc basins and strike-slip faulting, while sediment deposition from major rivers such as the Mekong contributed to the buildup of thick clastic sequences across the shelf.^[9]^[11] The Sunda Shelf lies within the interior of the Sunda Plate, an extension of the stable Eurasian Plate, characterized by low seismicity in its central regions due to minimal active tectonics, though margins experience high activity from features like the Sumatra Fault and Java Trench.^[12] This tectonic stability contrasts with the convergent margins, where ongoing subduction influences peripheral deformation but leaves the shelf core relatively undeformed since the Late Miocene.^[13] Sediment composition on the Sunda Shelf is dominated by Quaternary clastic deposits, including clays, silts, and sands derived from fluvial and marine sources, overlying Tertiary volcanic rocks and older basement lithologies such as granitic intrusions and metamorphic complexes.^[9]^[14] Sedimentary thicknesses reach 10-15 km in depocenters, particularly in rift-related basins formed during Eocene-Miocene extension, reflecting prolonged accumulation from both terrigenous inputs and volcanic contributions.^[9]^[15] Recent dynamics include subsidence at rates of 0.2-0.3 mm/year, driven by sediment loading, isostatic adjustment, and mantle convection, as evidenced by geomorphological and geophysical analyses from 2019 studies.^[16] This ongoing vertical motion, superimposed on the shelf's tectonic stability, influences its long-term evolution without significant seismic disruption in the interior.^[12]

Paleogeography

Exposure During Low Sea Levels

The Sunda Shelf, a vast shallow continental platform in Southeast Asia, emerged as dry land during episodes of lowered global sea levels, forming the paleolandmass known as Sundaland. This landmass connected the Indochinese mainland to the islands of Borneo, Sumatra, Palawan, and Java, spanning approximately 2.5 million km² at its maximum exposure when sea levels dropped below -120 meters.^[3] Such exposure unified what are now separated island ecosystems into a contiguous terrestrial bridge, facilitating faunal and floral exchanges across the region. Full connectivity of Sundaland occurred repeatedly during the Pleistocene epoch, from approximately 2.6 million to 11,700 years ago, when glacial conditions dominated global climate. The landscape was characterized by expansive marshy plains, open savannas, and forested areas, with the most extensive exposure during the Last Glacial Maximum around 21,000 to 18,000 years before present. At this peak, the shelf's submersion threshold was surpassed, creating a broad expanse of habitable terrain that extended southward from present-day Thailand.^[17] The topography of the exposed Sundaland consisted of central lowlands averaging less than 50 meters in elevation, fringed by hilly margins and dissected by major river valleys that drained into coastal lagoons and brackish wetlands. This configuration was bounded to the south by the deep-water Lombok Strait, which remained unsubmerged and separated Sundaland from the Sahul Shelf to the east, establishing an early barrier akin to Wallace's Line. Paleoenvironmental conditions across exposed Sundaland were markedly cooler and drier than modern tropics, with temperatures 3–6°C lower and enhanced seasonality driven by intensified monsoonal winds. These factors supported a mosaic of biomes blending tropical elements with subtropical adaptations, including grasslands and woodlands suited to periodic aridity.

Sea Level Fluctuations and Timeline

The sea level fluctuations affecting the Sunda Shelf are primarily driven by glacial-interglacial cycles, which are modulated by Milankovitch orbital forcings including variations in Earth's eccentricity, obliquity, and precession that alter the distribution and intensity of solar insolation.^[18] These cycles have caused global eustatic sea levels to oscillate by approximately 120-150 meters over the Pleistocene, with major lowstands reaching about -130 meters below present during Marine Isotope Stages (MIS) 2, 4, and 6, corresponding to peak glacial periods.^[19] On the subsiding Sunda Shelf, with a subsidence rate of 0.2-0.3 mm/year, these global changes interacted with local tectonics to control exposure and submergence patterns.^[16] The timeline of significant exposure began with the intensification of Northern Hemisphere glaciation at the Pliocene-Pleistocene boundary around 2.58 million years ago, marking the onset of repeated lowstands that periodically exposed the shelf.^[20] Dominant 100,000-year eccentricity cycles governed subsequent fluctuations through the Pleistocene, with the Sunda Shelf remaining largely exposed prior to approximately 400 thousand years ago (ka) before transitioning to regular submersion-exposure cycles between 400-240 ka, intensifying after 250 ka.^[16] Following the Last Glacial Maximum (LGM) around 21-19 ka, when sea levels were at their lowest, rapid post-glacial rises occurred, including Meltwater Pulse 1A (MWP-1A) from 14.6-14.3 thousand years before present (kyr BP), which raised levels by 16 meters at rates up to 40-50 mm/year, as recorded in Sunda Shelf sediments. These cycles resulted in intermittent land bridges across the shelf lasting 50,000-100,000 years per glacial phase, facilitating biogeographical connections.^[20] The final major submergence of the Sunda Shelf to near-modern levels occurred between 8,000-6,000 years BP during the mid-Holocene, as sea levels stabilized after the rapid deglacial rises.^[21] Throughout the late Holocene, the shelf has experienced relative stability with minor variations of 1-2 meters, influenced by the region's tectonic quiescence and isostatic adjustments.^[22] Looking forward, climate change projections indicate potential sea level rises of up to 1 meter by 2100 in Southeast Asia, including the Sunda Shelf area, driven by thermal expansion and ice melt, which could exacerbate submergence risks.^[23]

Submerged Features

Paleo River Systems

The paleo river systems of the Sunda Shelf formed extensive drainage networks during periods of lowered sea levels, particularly the Last Glacial Maximum (LGM) around 21,000 years ago, when the shelf was largely exposed. Major systems included the Siam River, a proto-system combining the modern Mekong and Irrawaddy drainages, which extended across the northern and central shelf; the Malacca River, draining proto-rivers from Sumatra and the Malay Peninsula through the Straits of Malacca; the Northern Sunda River (also known as the Molengraaff River), linked to the proto-Red River and channeling waters from Indochina southward; and the Eastern Sunda River, facilitating drainage between Java and Borneo. These systems reached lengths of up to 1,500 km, with channel widths ranging from 10 to 50 km, forming a interconnected fluvial landscape that covered much of the exposed shelf area of approximately 1.8 million km².^[3]^[24]^[25] Reconstruction of these systems relies on bathymetric data interpolated to paleo-sea levels of -120 m, such as the GEBCO 2023 grid, combined with seismic profiling and sediment core analysis to trace incised valleys now filled with Holocene marine sediments. Recent 2024 studies have detailed these networks using multibeam sonar surveys to map preserved channels, meanders, and tributaries, revealing dendritic patterns and confluences, for instance, between the Siam and North Sunda rivers at the 120 m isobath. Evidence from over 8,000 km of seismic lines during cruises like SONNE 115 confirms valley incisions up to 50 m deep, with core samples showing transgressive sequences and microfossils indicative of fluvial-to-marine transitions around 13.5 ka.^[3]^[25]^[24] These rivers played a critical hydrological role by transporting massive sediment loads—estimated at around 500 million tons per year for the Siam system during exposure, comparable to the combined modern fluxes of the Mekong and Irrawaddy rivers—forming prograding deltas, clinoforms, and shelf-margin wedges that influenced regional ocean currents and nutrient distribution. The North Sunda River, for example, delivered high terrigenous inputs from a vast catchment including the Malay Peninsula and Borneo, building thick sedimentary sequences during lowstands. Geological preservation is evident in underwater channels detectable via side-scan sonar and core sampling, where meanders and tributaries remain intact beneath thin Holocene mud layers due to the shelf's low gradient and rapid post-glacial flooding.^[24]^[26]

Other Submerged Landforms

The Sunda Shelf hosts a variety of submerged landforms beyond paleo river systems, including incised valleys, karst towers, submerged deltas, and shelf-edge reefs, which formed or were modified during periods of subaerial exposure. Incised valleys, often exceeding 1,200 km in length, represent erosional channels carved into the shelf during lowstands, with fills comprising late Pleistocene sediments up to 50 m thick, as evidenced by seismic profiles off the coasts of Sumatra and Borneo. Karst towers, resulting from limestone dissolution under humid tropical conditions during exposure, create isolated pinnacles and depressions; these features, now partially submerged, contribute to the shelf's rugged bathymetry, particularly in areas of carbonate bedrock. Submerged deltas, such as the late Pleistocene delta in the Malacca Strait, exhibit fan-like deposits preserved at depths of around 50 m, reflecting progradational sequences from major river outflows. Shelf-edge reefs, developed along the outer margins during interglacial highs, include fringing structures that have been drowned and preserved under subsequent transgressions, with examples near the shelf break in the Java Sea. The Natuna Islands serve as residual highs, representing unsubmerged topographic prominences amid the otherwise drowned paleolandmass. Central to the shelf's subsurface structure are basins and depressions, including the Sunda Basin and Java Sea Basin, which act as subsidence zones accumulating thick sedimentary sequences. The Sunda Basin, located offshore Southeast Sumatra, features a central depocenter with up to 5 km of Cenozoic sediments, primarily from Paleocene to Pleistocene, driven by tectonic rifting and post-rift thermal subsidence. The adjacent Java Sea Basin exhibits similar architecture, with sediment thicknesses reaching 2.5–4 km in syn-rift sequences, overlain by Neogene clastics. Evidence for these features derives from oil and gas exploration cores and seismic data, which reveal half-graben structures and hydrocarbon reservoirs in the Talangakar Formation, confirming depositional environments from fluvial to marine transitions. Coastal paleolandforms from Last Glacial Maximum (LGM) coastlines are now submerged at depths of -20 to -50 m, preserving relict beaches, lagoons, and mangrove zones. These features indicate dynamic shorelines where mangroves flourished along exposed inner shelf margins during Marine Isotope Stage 3 (MIS 3), before retreating seaward in the LGM as sea levels dropped, with pollen and sediment cores from 83–92 m depths showing abrupt shifts around 23–20 ka BP. Submerged lagoons and beach ridges, identified in bathymetric anomalies, mark transgressive ravinement surfaces from deglacial rapid rise. These landforms have been mapped using multibeam echosounding and high-resolution seabed surveys, which reveal ~17,000-year-old topography through isobath reconstructions at 50–120 m depths. Compiled datasets from over 900 sonar cruises, such as the GEBCO 2023 grid, enable detailed visualization of paleo-surfaces, integrating with incised valley networks to delineate the shelf's paleotopography.

Biogeographical Importance

Sundaland as a Biodiversity Hotspot

Sundaland is recognized as one of the world's 36 biodiversity hotspots by the Critical Ecosystem Partnership Fund (CEPF), encompassing approximately 1.5 million km² across the Indonesian archipelago, Malay Peninsula, and the submerged Sunda Shelf.^[27] This region supports around 25,000 species of vascular plants, 60% of which are endemic, along with more than 1,800 vertebrate species, contributing to its exceptional biological richness. The high beta-diversity in Sundaland stems from historical isolation of habitats during Pleistocene sea level fluctuations on the Sunda Shelf, fostering unique evolutionary divergence among populations.^[28]^[29] The floral diversity of Sundaland is characterized by the dominance of dipterocarp trees, with over 265 species recorded in Borneo alone, forming the canopy of lowland rainforests. Orchids represent another major group, exceeding 2,000 species, while palms and other understory plants add to the complexity of these ecosystems. The primary centers of this plant richness are the extensive rainforests of Borneo and Sumatra, where endemic genera such as those in the Rafflesia family thrive, including the world's largest flower, Rafflesia arnoldii.^[28]^[30] Sundaland's fauna exhibits remarkable variety, with approximately 380 mammal species, about 45% of which are endemic, including flagship species like the Bornean orangutan (Pongo pygmaeus), Sumatran tiger (Panthera tigris sumatrae), and proboscis monkey (Nasalis larvatus). The region hosts around 770 bird species, featuring endemics such as various hornbills (Buceros spp.), and over 450 reptile species, including large monitor lizards like the Asian water monitor (Varanus salvator). Amphibians number more than 240 species, with nearly 200 endemics, underscoring the hotspot's role in global faunal diversity.^[28] Conservation in Sundaland faces severe threats from deforestation, which has resulted in over 90% loss of original forest cover, leaving approximately 100,000 km² of vegetation as of the early 2000s, driven by logging, palm oil plantations, and agriculture, leading to widespread habitat fragmentation. Recent assessments as of 2024 highlight a severe lack of data on freshwater biodiversity, impeding effective conservation amid ongoing climate change pressures.^[31] These pressures endanger endemic species and ecosystem services, with illegal wildlife trade exacerbating declines in populations of tigers and orangutans. Key protected areas, such as Gunung Leuser National Park in Sumatra—a UNESCO World Heritage site—cover critical habitats and support conservation efforts to preserve this biodiversity.^[32]^[33]^[30]

Endemism and Faunal Patterns

The Wallace Line, first identified by Alfred Russel Wallace in 1863, delineates a major biogeographic boundary along the deep-water channels of the Lombok and Makassar Straits, separating the Oriental faunal region of the Sunda Shelf from the Australasian biota to the east. This barrier persisted even during Pleistocene lowstands, preventing widespread faunal mixing and contributing to distinct evolutionary trajectories on either side.^[34] The line underscores the Sunda Shelf's role as an extension of Asian biogeography, with its fauna exhibiting predominantly Oriental characteristics. Pleistocene sea level fluctuations and resultant isolations on the Sunda Shelf promoted vicariance events, driving speciation and endemism through geographic fragmentation of habitats. These dynamics led to significant endemism among mammals, with local diversification processes contributing substantially to regional diversity; for instance, shrew populations (Crocidura spp.) show high levels of within-island endemism, illustrating how isolation fostered unique lineages. The proboscis monkey (Nasalis larvatus), endemic to Borneo within the Sunda Shelf, exemplifies this pattern, having evolved in isolated mangrove and riverine forests during glacial periods. Genetic studies further reveal east-west divergence, as seen in the 2022 analysis of Macaranga section Pruinosae trees, where basal splits separate western (Sumatra, Malay Peninsula) from eastern (Borneo) populations, reflecting Pleistocene vicariance across central Sundaland barriers.^[29] Faunal exchanges across the Sunda Shelf were predominantly unidirectional, with strong Asian affinities dominating the mammal assemblage, including species like the Asian elephant (Elephas maximus) and Sumatran rhinoceros (Dicerorhinus sumatrensis), which dispersed southward via land bridges during low sea levels.^[35] In contrast, Australian elements remained limited, with no marsupials establishing viable populations on the shelf, highlighting the Wallace Line's efficacy as a filter.^[34] Savanna corridors in central Sundaland during the late Pleistocene facilitated these Asian dispersals by creating open habitats that connected peninsular Malaysia to Borneo and Java, enabling migration of grassland-adapted taxa while restricting forest specialists.^[36] Contemporary phylogeographic patterns on the Sunda Shelf exhibit breaks at key straits, such as the Balabac Strait between Borneo and Palawan, where genetic discontinuities align with historical barriers to gene flow.^[37] DNA barcoding studies confirm these patterns, revealing cryptic diversity and lineage splits in taxa like freshwater fishes (e.g., Rasbora spp.) across Sundaland straits, underscoring ongoing influences of past isolations on current distributions.^[38]

Human and Archaeological Significance

Prehistoric Migration Pathways

The Sunda Shelf played a pivotal role in the southern dispersal route of anatomically modern humans (Homo sapiens) out of Africa, facilitating migration via India into Southeast Asia between approximately 70,000 and 50,000 years before present (BP). This pathway connected the Indian subcontinent to the exposed continental shelf, forming a continuous land bridge that allowed early populations to traverse what is now the Malay Peninsula and surrounding islands. From Sundaland, further dispersal occurred eastward toward Sahul (the combined landmass of Australia and New Guinea), with evidence indicating arrival in northern Australia around 65,000 BP, likely following coastal and riverine corridors along paleo-river systems such as the ancient Sunda River.^[17]^[39] Archaeological evidence underscores these migration pathways, with key sites revealing human occupation and adaptations suited to the shelf's diverse environments. At Niah Cave in Borneo, human remains and artifacts date to at least 46,000 BP, including tools for hunting arboreal primates and processing tropical resources, indicative of sophisticated foraging strategies in rainforest settings. Similarly, Lang Rongrien Rockshelter in southern Thailand yields evidence of human activity from 42,000 to 27,000 BP, featuring stone tools and faunal remains that suggest exploitation of coastal and inland habitats. These sites, along with isotopic analyses from nearby Timor (e.g., Asitau Kuru at ~42,000 BP), demonstrate early reliance on marine shellfish, fish, and riverine resources, highlighting adaptations that enabled sustained movement across the exposed landscape. Recent 2024 genetic analyses have refined the timeline of these dispersals, suggesting potential earlier admixture events in the region.^[40]^[41]^[42] During periods of low sea levels, particularly the Last Glacial Maximum (~21,000 BP), the Sunda Shelf was exposed as a vast corridor approximately 2,000 km wide, rich in savannas, rivers, and coastal zones that supported human mobility and resource availability. This subaerial exposure more than doubled the landmass to approximately 2.5 million km², creating habitable pathways with access to freshwater, game, and marine foods, easing dispersal without the need for extensive seafaring. A 2023 paleogeographic and genetic study further reveals that subsequent rapid sea-level rises, such as Meltwater Pulse 1A (~14,500–14,000 BP), fragmented Sundaland by flooding low-lying areas, compelling populations to migrate northward toward South Asia and contributing to regional genetic diversification.^[43]^[17] Population dynamics during these migrations involved genetic bottlenecks, notably the initial out-of-Africa event around 60,000–70,000 BP, which reduced effective population sizes before re-expansion into Sundaland. Later isolations due to rising seas post-15,000 BP led to further bottlenecks and population splits, increasing density in surviving refugia by up to 8.6-fold in Island Southeast Asia. Additionally, Denisovan admixture is evident in modern populations across the region, particularly in Philippine Negritos and eastern Indonesian groups, stemming from interbreeding likely occurring in Sundaland or Wallacea around 50,000–40,000 BP, which introduced adaptive genetic variants for local environments.^[44]^[17]^[45]

Modern Environmental Impacts

The Sunda Shelf, a vast submerged continental platform underlying much of the South China Sea and adjacent waters, is experiencing ongoing submergence due to global sea level rise, which exacerbates coastal erosion along the shorelines of Indonesia and Malaysia.^[46] According to IPCC AR6 (2021), global sea level is projected to rise 0.28–1.01 meters by 2100 depending on emissions scenarios (SSP1-2.6 to SSP5-8.5), with regional increases in Southeast Asia potentially 10–20% higher due to ocean dynamics, thermal expansion, ice melt, and local subsidence.^[47] This rise threatens mangrove ecosystems, which cover approximately 12,350 km² in the Sunda Shelf ecoregion and serve as critical buffers against erosion, by promoting inundation and sediment loss if vertical accretion fails to keep pace.^[48] Fisheries are also impacted, as altered coastal habitats and increased salinity disrupt fish stocks and livelihoods for millions in Indonesia, where the sector contributes 2.6% to GDP and supports over 7 million jobs.^[49] Human activities further degrade the Sunda Shelf's marine environment, including oil and gas extraction in fields like the Natuna Sea, where drilling discharges contaminated cuttings into shallow waters, leading to sediment pollution and long-term toxicity in surrounding ecosystems.^[50] The Malacca Strait, a key shipping lane traversing the shelf, sees heavy vessel traffic that discharges oil, chemicals, ballast water, and solid waste, posing risks to coral reefs, mangroves, and fisheries through spills and habitat disruption.^[51] Overfishing in these waters, with intense effort levels exceeding 100 kg/km² in northern and southern sections of the strait, depletes fish populations and exacerbates ecosystem imbalance.^[52] Pollution from river outflows, such as those from the Mekong and major Indonesian rivers, introduces nutrients and contaminants that contribute to eutrophication and habitat degradation across the shelf.^[51] Subsidence in the Mekong Delta, part of the Sunda Shelf's eastern margin, occurs at rates of 3.4 to 11.3 mm/year, outpacing global sea level rise by up to four times and driven by sediment compaction, groundwater extraction, and damming.^[53] This sinking promotes saltwater intrusion extending over 50 km inland, with salinity increases of 0.2–0.5 PSU/year, threatening agriculture and freshwater ecosystems.^[53] Geological analyses from 2019 highlight natural compaction of Holocene sediments as a key factor, amplifying vulnerability in low-lying deltas.^[54] Conservation efforts aim to mitigate these impacts through marine protected areas (MPAs) overlapping the Coral Triangle, which encompasses Sunda Shelf regions in Indonesia and Malaysia. As of 2014, over 157,000 km² were protected in Indonesia, covering 31% of coral reefs; more recent data indicate total MPAs exceed 230,000 km², protecting about 13% of coral reefs.^[55]^[56] UNESCO initiatives, such as the Tropical Rainforest Heritage of Sumatra World Heritage Site spanning 2.6 million hectares across three national parks, support biodiversity conservation in adjacent Sundaland ecosystems through anti-poaching patrols, stakeholder forums, and enforcement against encroachment.^[30]

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Savanna in equatorial Borneo during the late Pleistocene - Nature
Apr 25, 2019 · A north-south savanna corridor from peninsular Malaysia, through central Sundaland during glacial periods would represent a 'barrier' for ...Missing: fauna | Show results with:fauna
[35]
Integrating phylogenetic and taxonomic evidence illuminates ...
Aug 7, 2025 · A northwards branch of Wallace's Line called Huxley's Line sets a biogeographical break between Sundaland and the Philippines to the east.
[36]
Intraspecific diversity and phylogeography of bony lip barb ...
We investigate how this interplay has shaped patterns of genetic variation and phylogeographic structure within this species in the Sundaland, a biodiversity ...
[37]
When did Homo sapiens first reach Southeast Asia and Sahul? | PNAS
Aug 6, 2018 · Estimated fossil ages range from 36 to 220 ka; most fall in the interval 40–120 ka. Most age estimates are based on U-series analyses of ...
[38]
A multi-proxy approach to exploring Homo sapiens' arrival ... - Nature
Oct 26, 2021 · From 46 ka, at Niah cave in Borneo, modern humans efficiently exploited the tropical environments, using sophisticated hunting technologies ...
[39]
Late Pleistocene human paleoecology in the highland savanna ...
Aug 18, 2021 · ... human migration prior to crossing through the Sunda Shelf during a period of glaciation (Fig. 1). In terms of paleoenvironments, much ...Missing: pathways | Show results with:pathways
[40]
Isotopic evidence for initial coastal colonization and subsequent ...
Apr 29, 2020 · The results demonstrate that the earliest human forager found in the region c. 42,000 years ago made significant use of coastal resources prior ...
[41]
Soils on exposed Sunda Shelf shaped biogeographic patterns in the ...
Migration of Early Humans Through Sundaland. The presence of a savanna corridor in central Sundaland has been used as an argument for the rapid dispersal of ...Missing: prehistoric pathways
[42]
Hominin population bottleneck coincided with migration from Africa ...
Mar 11, 2024 · The timing and causes of hominin (pre-Homo sapiens) migrations out of Africa have been of recent interest. Two scenarios, one based on ...Missing: prehistoric | Show results with:prehistoric
[43]
Widespread Denisovan ancestry in Island Southeast Asia but no ...
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[44]
The impact of climate change on coastal erosion in Southeast Asia ...
Feb 29, 2024 · Coastal erosion and tidal flooding resulting from rising relative sea levels have threatened community livelihoods and physically degraded the ...
[45]
[PDF] Impact of Climate Change – Sea Level Rise Projections for Malaysia
The results show that the projected sea level rise along Peninsular Malaysia, Sarawak and Sabah coastline at year. 2100 is 0.25 to 0.52m, 0.43 to 0.64m, and ...
[46]
[PDF] Climate Change - GFDRR
Mangrove systems are also already feeling the effects of climate variability and change; reduced freshwater flows and sea-level rise as well as human activities ...Missing: erosion | Show results with:erosion<|separator|>
[47]
Mangroves of the Sunda Shelf - IUCN Ecosystems
In the future, the mangrove ecosystem will be threatened by sea level rise (SLR) and more than 30% of the Sunda Shelf mangrove extent could be submerged by 2070 ...
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Hot Water Rising: The Impact of Climate Change on Indonesia's ...
Nov 7, 2023 · Climate change is driving the increase in water temperatures, storm severity, sea level rise, and causing shifts in coastal ecosystems and fisheries.Missing: projections Malaysia 2100 0.3-1 meter mangroves Sunda Shelf
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Environmental Impacts Of The Oil And Gas Platform Decommissioning
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[50]
Straits of Malacca – MIMA - Maritime Institute of Malaysia
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[51]
Sustainable Fisheries, Environment and the Prospects of Regional ...
Heavy fishing activities (100-999.9 kg/km2) are recorded in the northern and southern Malacca Strait, along the east coast of the Malay Peninsula, in the ...
[52]
Water-level changes and subsidence rates along the Saigon-Dong ...
Apr 5, 2023 · Subsidence along the Mekong Delta coastline (3.4 to 11.3 mm/yr) is up to four times higher than the global sea-level rise.
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Tidal amplification and salt intrusion in the Mekong Delta driven by ...
Dec 10, 2019 · While offshore M2 tidal amplitude increases by 1.2–2 mm yr−1 due to sea level rise, tidal amplitude within the delta is increasing by 2 cm yr−1 ...Changes In Salinity And Tide · Bed Level Changes · Sediment StarvationMissing: mantle- | Show results with:mantle-
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### Summary of Marine Protected Areas in the Coral Triangle Overlapping with the Sunda Shelf