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Abstract. The Indo-Pacific Pollen Database (IPPD) is the brainchild of the late Professor Geoffrey Hope, who gathered pollen records from across the region to ensure their preservation for future generations of palaeoecologists. This noble aim is now being fulfilled by integrating the IPPD into the online Neotoma Palaeoecology Database, making this compilation available for public use. Here we explore the database in depth and suggest directions for future research. The IPPD comprises 226 fossil pollen records, most postdating 20 ka, but some extending as far back as 50 ka or further. Over 80 % of the records are Australian, with a fairly even distribution between the different Australian geographical regions, the notable exception being Western Australia, which is only represented by 3 records. The records are also well distributed in modern climate space, the largest gap being in drier regions due to preservation issues. However, many of the records contain few samples or have fewer than 5 chronology control points, such as radiocarbon, luminescence or Pb-210 for the younger sequences. Average sedimentation rate for the whole database, counted as years per cm, is 64.8 yr/cm, with 61 % of the records having a rate of less than 50 yr/cm. The highest sedimentation rate by geographical region occurs on Australia’s east coast, while the lowest rates are from the Western Pacific. Overall, Australia has a higher sedimentation rate than the rest of the Indo-Pacific region. The IPPD offers many exciting research opportunities, such as examination of human impact on regional vegetation, contrasting first human arrival and colonisation, and assessment of rates of vegetation change during the Holocene. Merging the IPPD into Neotoma also facilitates inclusion of data from the Indo-Pacific region into global syntheses.
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Ecosystem change and human-environment interactions of Arabia
The Arabian Peninsula hosts some of the most extreme environments in the world. Arabian ecosystems are largely semi-arid to hyper-arid and yet are often highly biodiverse and unique owing to a location at a biogeographic nexus. There is an urgent need to better understand ecosystem resilience to biotic and abiotic disturbance; however, the modern vegetation across much of the sub-continent is still poorly understood. Palaeoecological records in Arabia have the potential to fill in gaps in our fundamental understanding of vegetation responses to climate, disturbance, and human modification; however, to do this, data must be accessible and easy to find. To this end, within the framework of the relaunch of the African Pollen Database, here we review existing palaeoecological datasets from the Arabian Peninsula, inventory those which are available, and synthesize results from these records. Due to the dearth of pre-Holocene information, this synthesis focuses on reconstructing vegetation from the Holocene Humid Period to today with emphasis on the impact of aridification and changing human livelihoods and culture on landscapes. Finally, as Arabia is perhaps the least well-studied region within the African Pollen Database, we offer some suggestions about fruitful directions for future palaeoecological research in this area.
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- Award ID(s):
- 1929563
- PAR ID:
- 10426874
- Date Published:
- Journal Name:
- Palaeoecology of Africa
- Volume:
- 35
- ISSN:
- 2372-5893
- Page Range / eLocation ID:
- 157-182
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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