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Earth and Life Sciences Open Programme X Geo and Biosphere from Molecule to Organism Please indicate the sub-area of the ALW field (see the ALW guide...
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Earth and Life Sciences

Open Programme X Geo and Biosphere from Molecule to Organism Please indicate the sub-area of the ALW field (see the ALW guideline) prof. dr. H. Hooghiemstra Kruislaan 3128, 1098 SM Amsterdam, The Netherlands Tel / Fax: 020-5257857 / 5257832 Mauritius since the last ice-age; reconstructing environmental dynamics and anthropogenic degradation of an island ecosystem (Name and address of the applicant, project title and an executive summary are provided through the on-line electronic submission system and will be automatically inserted at the front of the application) 1a. Further details of the main applicant Gender: male Tenure Position: yes Research School: Inter-universitary Centre of Geo-ecological Research (ICG) Website URL: http://staff.science.uva.nl/~jboxel/Hooghiemstra/ 1b. Alternative contact Name: dr B. van Geel Tel / Fax: 020 5257664 / 020 5257832 Email: [email protected] 1c. Does the local authority support your application? yes (did you inform your superior and accepts your institute/university the conditions for support by NWO) 1d.Renewed application? no (in case of renewed application please summarize main changes under item 4) Dossier nr: 1e. Applying for: X PhD student Postdoc X Research costs (for PhD student please underline promotor in question; 1f, composition of research group) 1f. Composition of the research group Name and title: prof. dr H. Hooghiemstra dr B. van Geel dr K. F. Rijsdijk dr. ir. J. van Boxel mrs A. Philip < PhD student > dr C. Baider dr F.B. Florens prof. dr. ir. J. van der Plicht dr M. Vélez prof. dr J. Vandenberghe

Specialization: Employment/Institute/time: palaeo-ecology / palaeoclimatology; UvA-IBED (2 h) palaeo-ecology / palaeoclimatology; UvA-IBED (2 h) physical geography; historical data input; NATURALIS & UvA-BED. PI ‘Dodo Research Project’ (1 h) climatology, ENSO variability; UvA-IBED (1 h) preparation pollen/diatom samples; UvA-IBED (4 h) palaeo-ecology / palaeoclimatology; UvA-IBED (38 h) ecology of the Mascarenes; Mauritius Herbarium/MSIRI (p.m.) ecology of the Mascarenes; Univ. of Mauritius (p.m.) radiocarbon dating; CIO, Groningen Univ. (0.5 h) diatom palaeo-ecolology; Regina Univ., Canada (0.5 h) grain size analysis; Vrije Universiteit Amsterdam (0.5 h)

2. Populaire samenvatting van de aanvraag (Nederlands) (if granted, this description will be used for Dutch communication, also to non-specialists)

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Open Programme Het afgelegen en geologisch jonge eiland Mauritius (20° ZB) heeft een hoge biodiversiteit ontwikkeld terwijl het Pleistocene klimaat vanwege de ligging van het eiland een sterke nat-droog afwisseling moet hebben gehad met een aanzienlijke dynamiek van de ecosystemen als gevolg. Op basis van 4 sedimentkernen reconstrueren we voor de laatstre 20.000 jaar (20 kyr) ijstijd-gestuurde temperatuurverandering, precessie-gestuurde nat-droog veranderingen (vooral 10 kyr cycli), en daarop gesuperponeerde snellere veranderingen variërend van millennium tot El Niño schaal. Op basis hiervan kunnen we de relevante componenten van het klimaatsysteem bepalen en hun werking verhelderen en de rol van het rijzen van de zeespiegel op de eilandecosystemen. We evalueren in welke mate het vulkanische mozaïeklandschap en het rivierbegeleidend bos een rol heeft gespeeld in het behouden van biodiversiteit onder klimatologisch ongunstige omstandigheden, De mogelijke rol van de Indian Ocean hot water pool als factor die ecosysteemdynamiek stabiliseert wordt geëvalueerd. Met de komst van Europeanen in 1638 AD zijn de natuurlijke ecosystemen sterk verstoord geraakt met als gevolg o.a. het uitsterven van de Dodo. De 4000 jaar oude concentraties van Dodo-botten en andere fossielen kunnen in deze lange reconstructies ingekaderd worden en de redenen van het ontstaan van de dodografvelden worden onderzocht. We maken een baseline study van de laatste eeuwen voor de komst van de mens (pre-1600 AD) die de blauwdruk vormt voor management en restauratieactiviteiten. Frangmenten rivierbegeleidend bos vormen thans het belangrijkste reservoir van resterende terrestrische biodiversiteit en we geven de hypothese vorm dat onder natuurlijke condities deze bossen als corridors functioneren om een dynamische respons op klimaatvariabiliteit mogelijk te maken. The remote and geologically young island of Mauritius developed a high biodiversity while for its geographical location Pleistocene climate must have experienced strong wet-dry alternations, causing dynamically changing ecosystems. Climate variability is driven by glacial/interglacial temperature change, precession-driven wet/dry changes (~10 kyr cycles), and superposed fast changes from millennial to El Niño time scales. In this project we reconstruct on the basis of 4 sediment cores the dynamics during the last 20 kyr of Mauritius’ ecosystems (wet montane forest, raingreen forest, dry forest, savanna) and the dynamic abiotic coastal environment. We evaluate how the mosaic of volcanic landscapes and gallery forests along the drainage systems has fascilitated conservation of biodiversity during climatologically unfavourable periods, and the impact of the raising sea-level on terrestrial ecosystems. The possible role of the Indian Ocean hot water pool as a factor stabilizing environmental change will be addressed. Natural ecosystems became rapidly degraded after Europeans arrived in AD 1638; the dodo became extinct. The 4000 years old dodo graveyard will be placed in a long-range record of changing regional and local conditions and we expect to better understand the reasons why this exceptional concentration of dodo-skeletons were formed. We will make a baseline study of the natural setting just before human impact (pre-1600 AD) that serves as a blueprint for management and restoration. Remnants of riverine gallery forest are now the reservoirs of terrestrial biodiversity left and we will elaborate on the hypothesis that under natural conditions such forests allowed a dynamic respons on climate variability. 3a. Top 5 scientific publications of the applicants related to the proposed research (members of the research team underlined) 1 Berrio, JC, Hooghiemstra, H et al., 2002. Late-glacial and Holocene history of the dry forest area in the south Colombian Cauca Valley. J. Quat. Sci. 17, 667-682. 2 Marchant, R, Hooghiemstra, H, 2004. Rapid environmental change in African and South American tropics around 4000 years before present: a review. Earth-Sci. Rev. 66, 217-260. 3 Rijsdijk, KF, Hume, JP, Bunnik, F, Florens, FB, Baider, C, Shapiro, B, Van der Plicht, J & 14 other authors, in press. Mid-Holocene concentration Lagerstätte in oceanic island Mauritius provides a window into the dodo ecosystem (Raphus cucullatus). Quat. Sci. Rev., in press. 4 van Geel, B, 2001. Non-pollen palynomorphs. In: J.P. Smol, Birks, H.J.B., Last, W.M. (eds.), Tracking environmental change using lake sediments; Vol. 3: Terrestrial, algal and silicaceous indicators. Kluwer, Dordrecht, p. 99-119.

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Open Programme 5 van Geel, B et al., 2003. Environmental reconstruction of a Roman Period settlement site in Uitgeest (The Netherlands), with special reference to coprophilous fungi. J. Archaeol. Sci. 30, 873-883.

3b. Other relevant publications (max 1 page, min 10 pts) 6 Almeida-Lenero, L, Hooghiemstra, H, Cleef, A, van Geel, B, 2005. Holocene climatic and environmental change from pollen records of lakes Zempoala and Quila, Mexico. Rev. Palaeobot. Palynol. 136, 63-92. 7 Aptroot, A, van Geel, B, 2006. Fungi of the colon of the Yukagir Mammoth and from stratigraphically related permafrost samples. Rev. Palaeobot. Palynol. 141, 225-230. 8 Behling, H, Hooghiemstra, H, 1999. Environmental history of the Colombian savannas of the Llanos Orientales since the Last Glacial Maximum from pollen records. J. Paleolimn. 21, 461-476. 9 Berrio, JC, Behling, H, Hooghiemstra, H, 2000. Tropical rainforest history from the Colombian Pacific area: a 4200-year pollen record from Laguna Jotaordó. The Holocene 10, 749-756. 10 Berrio, JC, Hooghiemstra, H, van Geel, B et al., 2006. Environmental history of the dry forest biome of Guerrero, Mexico, and human impact during the last c. 2700 years. The Holocene 16, 63-80. 11 Berrio, JC, Hooghiemstra, H et al., 2000. Late Holocene history of savanna gallery forest from Carimagua area, Colombia. Rev. Palaeobot. Palynol. 111, 295-308. 12 Berrio, JC, Arbelaez, MV, (..), Hooghiemstra, H, 2003. Pollen representation and successional vegetation change on sandstone plateau of Araracuara, Colombian Amazonia. Rev. Palaeobot. Palynol. 126, 163-181. 13 Hooghiemstra, H, van Geel, B, 1998. World list of Quaternary pollen and spore atlases. Rev. Palaeobot. Palynol. 104, 157-182. 14 Hooghiemstra, H, Van der Hammen, T, 2004. Quaternary ice-age dynamics in the Colombian Andes: developing an understanding of our legacy. Phil. Tr. R. Soc. Lond. B 359, 173-181. 15 Hooghiemstra, H. Wijninga, VM, Cleef, A, 2006. The paleobotanical record of Colombia: implications fror biogeography and biodivrsity. Ann. Missouri Bot. Gard. 93, 297-324. 16 Islebe, GA, Hooghiemstra, H, 1997. Vegetation and climate history of montane Costa Rica since the Last Glacial. Quat. Sci. Rev. 16, 589-604. 17 Marchant, R, Behling, H, Berrio, JC, Hooghiemstra, H et al., 2002. Pollen-based biome reconstructions for Colombia at 3, 6, 9, 12, 15 and 18 14C kyr ago: tropical vegetation dynamics. J. Quat. Sci. 17, 113-129. 18 Marchant, R, Behling, H, Berrio, JC, Hooghiemstra, H, van Geel, B et al., 2001. Mid- to Late-Holocene pollen-based biome reconstructions for Colombia. Quat. Sci. Rev. 20, 1289-1308. 19 Marchant, R, Boom, A, Behling, H., Hooghiemstra, H et al., 2004. Colombian vegetation at the Last Glacial Maximum: a comparison of model- and pollen-based biome reconstructions. J. Quat. Sci. 19, 721-732. 20 Mumbi, C, Marchant, R, Hooghiemstra, H, Wooler, MJ, 2008. Late Quaternary vegetation reconstruction from the Eastern Arc Mountains, Tanzania. Quat. Res. 69, 326-341. 21 Torres, V, Vandenberghe, J, Hooghiemstra, H, 2005. An environmental reconstruction of the sediment infill of the Bogotá Basin (Colombia) during the last 3 Ma from abiotic and biotic proxies. Palaeo3 226, 127-148. 22 Van der Hammen, T, Hooghiemstra, H 2000. Neogene and Quaternary history of vegetation, climate and plant diversity in Amazonia. Quat. Sci. Rev. 19, 725-742. 23 van Geel, B, 1978. A palaeoecological study of Holocene peat bog sections in Germany and the Netherlands. Rev. Palaeobot. Palynol. 25, 1-120. 24 van Geel, B, Van der Hammen, T, 1978. Zygnemataceae in Quaternary Colombian sediments. Rev. Palaeobot. Palynol. 25, 377-392. 25 van Geel, B et al. 1981. A palaeoecological study of an upper Late Glacial and Holocene sequence from "De Borchert", The Netherlands. Rev. Palaeobot. Palynol. 31, 367-448. 26 van Geel, B et al., 1983. A Late Holocene deposit under the Westfriese Zeedijk near Enkhuizen: palaeoecological and archaeological aspects. Rev. Palaeobot. Palynol. 38, 269-335. 27 van Geel, B et al. 1989. Palaeoecology and stratigraphy of the Lateglacial type section at Usselo (The Netherlands). Rev. Palaeobot. Palynol. 60, 25-129. 28 van Geel, B, 1994. Fossil akinetes of Aphanizomenon and Anabaena as indicators for medieval phosphateeutrophication of Lake Gosciaz. Rev. Palaeobot. Palynol. 83, 97-105. 29 van Geel, B, Grenfell, HR, 1996. Spores of Zygnemataceae. In: Palynology: principles and applications, Jansonius, J., McGregor, D.C. (eds); AASP Foundation, Vol. 1, 173- 179. 30 van Geel, B, Aptroot, A et al., 2008. The ecological implications of a Yakutian mammoth’s last meal. Quat. Res. 69, 361-376. 31 van Geel, B, Aptroot, A, 2006. Fossil ascomycetes in Quaternary deposits. Nova Hedwigia 82, 313-329.

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Open Programme 32 van ’t Veer, R, Hooghiemstra, H,, 2000. Montane forest evolution during the last 650,000 yr in Colombia: a multivariate approach based on pollen record Funza-1. J. Quat. Sci. 15, 329-346. 33 Vélez, MI, Berrio, JC, Hooghiemstra, H et al., 2005. Palaeoenvironmental changes of the last ca. 8590 cal yr in the dry forest ecosystem of the Patia Valley: a multiproxy approach. Palaeo3 216, 279-302. 34 Vélez, MI, Wille, M, Hooghiemstra, H et al., 2001. Late Holocene environmental history of southern Chocó region, Pacific Colombia; sediment, diatom and pollen analysis. Palaeo3 173, 197-214. 35 Weng, C, Hooghiemstra, H, Duivenvoorden, J, 2006. Challenges in estimating past plant diversity from fossil pollen data: statistical assessment, problems, possible solutions. Diversity Distrib. 12, 310-318. 36 Wille, M, Hooghiemstra, H, van Geel, B et al., 2003. Submillennium-scale migrations of the rainforestsavanna boundary in Colombia: 14C wiggle-matching and pollen analysis. Palaeo3 193, 201-223. 37 Wille, M, Hooghiemstra, H et al., 2001. Environmental change in the Colombian subandean forest belt from 8 pollen records: the last 50 kyr. Veget. Hist. Archaeobot. 10, 61-77.

Figure 1. Inset: Mauritius located in the Indian Ocean (see circle). Main figure: location of coring site Mare Tattos (TAT), site Mare Grand Bassin (GB), site Trou Kanaka (KAN), and the dodo bone bed site Mare aux Songes (MAS).

4. Detailed description of research area and research plan (max 4 pages, min 10 pts) (detailed description of objectives, innovative aspects, methodology) Acronyms used: DRP=Dodo Research Program; EAM=Eastern Arc Mountains (Tanzania); GB=Grand Bassin; ITCZ=Intertropical Convergence Zone; KAN=Kanaka Crater; LGM=Last Glacial Maximum; MAS=Mare aux Songes; NPP=Non-Pollen Palynomorphs; TAT=Mare Tattos.

INTRODUCTION - Studies of climate change-driven migration of ecosystems document the dynamic history of tropical ecosystems. In tropical mountain areas temperature change drive plant communities/biomes vertically (altitudinally) (e.g. 6, 14, 16, 17, 18, 37), while in tropical lowlands changes in precipitation in particular drive plant communities/biomes horizontally (latitudinally) (e.g. 8, 11, 12, 33, 36). Sea-level rise drive migration of coast lines (e.g. 9, 34) and lake-level changes drive migration of lake shores (21, 32). These aspects of the dynamic history of tropical ecosystems in Central and Northern South America, and in East Africa (20), were intensively studied in the research group of Hooghiemstra during the past three decades (> 50 publications; see website Hooghiemstra). On mountain peaks in the Northern Andes lies an ‘archipelago of islands’ with páramo vegetation (i.e. tropical alpine vegetation above the Upper Forest Line at 3200 m alt.). Remarkably enough, in the Northern Andes highest plant diversity is located at places (Cocuy area) where the mountains have their youngest geological history as they were uplifted not before 6 million years ago (50% of Pleistocene time) when sea-level stands were 80-120 m lower than today does not offer migratory options. Ecosystems in Mauritius possibly do have alternative mechanisms to respond to climate change and common believe is growing that riverine gallery forests play a crucial role (79). Here we arrive at an important research question in palaeoecology, biogeography, and biodiversity: how dynamic was the Pleistocene environment on Mauritius, and how did wet and dry ecosystems survive the repetitive periods of opposite climatic conditions? (1, 10, 12, 79). From explorative field work and pilot studies in Mauritius it became clear that we can infer the specific characteristics of the environmental history from long high-resolution multiproxy records from a lowland raingreen forest (site Tattos at 10 m elevation will show 8000 years of history) and from crater lakes in wet montane forest (site Kanaka at 740 m elevation will show >30,000 years of history; site Grand Basin at 580 m elevation will show 10,000 years of history). In 2005 European and Mauritian researchers discovered a fossil bed (site Mare aux Songes; MAS) that contained remains of the dodo and other extinct animals and plant species (61). This fossil bed (‘dodo graveyard’) was radiocarbon dated 4000 years old and contains much fossil evidence of the local conditions at that time (3). It is unclear which natural conditions have caused (2) the death and concentration of so many animals in one location 4000 years ago. The presence in Mauritius of undisturbed lake sediments and peat deposits representing the last >20 kyr enable to reconstruct natural environmental and climatic variability during a full precession cycle, thus including the full amplitude of wet and dry conditions representative for the Pleistocene (38, 58). The sudden colonization that started in the 17th century by the Dutch (42) which left rich historical and archaeological archives, documents with precision the process of human impact on the natural ecosystem. The combination of natural and abundant documentary information for the last 400 years is unique for a tropical island and offers possibilities to calibrate the records based on fossils (67) against the written documentary archive. OBJECTIVES - In this research project we will aim at the following deliverables: - a multiproxy reconstruction of environmental and climatic change since the Last Glacial Maximum (LGM) at 20 kyr BP of montane forest, lowland raingreen (semi-deciduous) forest, riverine gallery forest, and savanna ecosystems, with special attention for documenting dry climatic events, and submillennial-scale climate frequencies; - a reconstruction of the timing and the impact of Lateglacial and early Holocene sea-level rise on terrestrial ecosystems based on downcore grain size distributions (indicating changing energy levels of sediment input in TAT), and diatoms (indicating changes from fresh to brackish water conditions and changing trophic conditions); - a baseline study of the natural setting before human impact (pre-1600 AD) that serves as a blueprint for management and restoration: providing a basis for conservation of riverine forest corridors for connectivity to maximize species response capacity in the face of future climate change and continuing landscape degradation (79); - elaboration on the hypothesis that remnants of riverine gallery forest allowed a dynamic response on climate variability under natural conditions (compare 44, 59, 71, 76); - a pollen-based account of plant introductions during the last 400 years. Known introduction events (39, 47, 65, 71) are cross-checked by first appearance dates in the pollen record;

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Open Programme - a multiproxy account of human impact on the environment (deforestation, increasing erosion) leading to the present-day degraded and agricultural landscape (1); - to collect evidence that clarifies the presence of an unprecedented bone bed in the coastal pools of MAS; pollution (phosphate; blooms of toxic nitrogen-fixing cyanobacteria) may have caused the death of so many dodos, tortoises and related fauna; - an island vs. continent comparison of glacial and Holocene environmental change (nature and rates of change) by using records from Madagascar (e.g. 43, 46, 51, 52, 75), tropical Africa (e.g. 40, 50, 62, 70), and tropical South America (2, 38, 56) to evaluate Mauritius’ specific environmental conditions; - to communicate scientific results in international journals and among relevant parties in Mauritius (University of Mauritius, Royal Society of Arts and Science of Mauritius, governmental institutes, NGOs, l’Institut de Recherches Sucrieres / MSIRI). - < Note: Where possible we are keen to introduce information from (molecular) geochemistry and stable isotopes on a basis of inter-institute collaboration; this is no formal part of this proposal > METHODS & RESEARCH PLAN Sediment cores - Fossil-based evidence comes from a number of sediment cores which have been collected during 2007 and 2008, or will be collected in 2009 by the PhD student (all sites have been carefully prospected by Hooghiemstra and Rijsdijk during fieldwork in July 2008). The potential to produce the information mentioned above is explained. - Site Mare Tattos (TAT; 10 m alt., 1200-1800 mm precip, T Jan/July: 27°/22°C)(63) in coastal semideciduous forest and savanna setting: a 640-cm core was collected in 2008; 3 14C ages show the record covers the last c. 8000 year. First interpretation of the core shows a coastal vegetation which is around 7000 yr BP increasingly flooded by marine incursions, documenting the effect of sea-level rise to the terrestrial environment. The local and coastal environmental changes are documented. - Site Mare aux Songes (MAS; 10 m alt.; 1200-1800 mm precip; T Jan/July: >28°/23°C) contains the fossil bone bed with a 14C age of 3700-4000 BP located in a coastal semi-deciduous forest and savanna setting. During the last 3 years sediment samples and cores were collected by the Dodo Research Programme (DRP; dr K. Rijsdijk PI). Microfossil analysis of these sediments will allow to reconstruct the local environment when these swamps were used by the Dodo and under which conditions these swamps became a graveyard (4, 5, 6, 7, 23, 24, 25, 26, 27, 28, 29, 30, 31). The site also represents evidence of the coastal environment more and recent introductions of exotic plant species (71, 73, 76). - Site Mare Grand Bassin (GB; 660 m alt.; >3600 mm precip; T Jan/July: 23°/17°C) in a wet montane forest setting: 440-cm of sediment has been identified in 2008 and will be cored in the frame of this project. A preliminary 340-cm long core collected in 2006 shows this sediment record reflects the last 11 kyr. This site archives with high precision temperature change (based on changes in the regional pollen spectra reflecting vertical migrations of the transition between lowland and montane vegetation and using a lapse rate of 0.6°C per 100 m vertical forest displacement (32, 37, 45, 69), changes in climatic humidity (based on changes in the spectra of aquatic plants reflecting lake-level changes (21, 32), and recent introductions of exotic plant species. Several introduced taxa (65, see also 71) can be pollen morphologically monitored (13, 68; we have the complete pollen morphological study of the Mascarenes by prof. H. Straka available). - Site Kanaka Crater (KAN; 560 m alt.; 3000-3600 mm precipitation; T Jan/July: 23°/15°C) is a spectacular funnel shaped crater with a diameter of 300 m in a wet montane forest setting. In 2008 we collected a 1000-cm long core. This crater most probably includes up to 20-m deep sediments. We estimate this record will reflect the last >30 kyr. According to the focus of this project we will analyse the last 20 kyr in most detail. This site archives with high precision temperature change (based on changes in the regional pollen spectra reflecting vertical migrations of the transition between lowland and montane vegetation, changes in climatic humidity and drought events (based on changes in the spectra of aquatic plants reflecting lake-level changes), recent introductions of exotic plant species, and show a fire history (based on charcoal analysis). Although not a part of this project, we will be alert to use our data in paleodata-model comparisons (19).

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Open Programme Reconstruction of change at an island scale - According to literature (e.g. 41, 45, 69) in the tropics at sea-level temperatures during the Last Glacial Maximum (LGM) at 20 kyr BP were c. 5°C lower compared to today. At 2500 m elevation LGM temperature were 8-9°C lower (e.g. 32). Our working hypothesis is that at the Kanaka site (740 m alt.) LGM temperatures were c. 6-7°C lower than today when a small ‘top effect’ in these low mountains is anticipated. Therefore, our working hypothesis assumes the following changes in biome surface (63, 72, 74) when present-day setting and island surface (= 100%) is compared to the LGM setting (5-7°C cooler, and sea-level 100-120 m lower) and island surface (c. 140%): - semi-deciduous/dry lowland vegetation (0-250 m alt.): from c. 75% to c. 87% surface at LGM - lowland/lower montane forest (250-500 m alt.): from 20% to 10% surface at LGM - wet montane forest (500-800 m alt.): from 5% to 3% surface at LGM A modern-to-LGM temperature change of 5-7°C, and a significant potential precipitation change of some 2000 mm would allow us to reconstruct regional environmental and climatic change adequately based on fossil pollen, seeds, organic C-content, grain size analysis, and possibly also geochemistry. The age models of the 4 sediment records will be based on an anticipated number of c. 36 radiocarbon ages. In case 14C wiggle match dating is promising (78) a larger number of 14C ages will be dated with additional funds of the research group. Reconstruction of change at a local scale - During the past 35 years van Geel has paid special attention to Quaternary non-pollen palynomorphs (NNP), such as fungal remains, algae, cyanobacteria, and invertebrate remains (4, 5, 6, 7, 23, 24, 25, 26, 27, 28, 29, 30, 31). Several hundreds of different ‘Types’ were published, some of which appeared to be very sensitive indicators for changes in past environments, changes in biodiversity, and presence of human impact. Our experience bears witness that NPP are very useful, in studies of natural change in lake and peat deposits and in human impact studies of archaeological sites. Man and domesticated animals will have been responsible for a range of new habitats at sites TAT, GB, KAN in particular (47, 49, 71), and also the mycoflora of settlement sites and the surrounding arable land and pastures will have had different fungal assemblages relative to undisturbed natural ecosystems. In most cases recorded fungal spores are of strictly local occurrence; thus they are able to record local change. They fossilised at, or near, the places were they had been produced, or the spores were deposited at short distance from the place where sporulation took place (4). The following four groups of fungi will be used: - Indicators of endemic diversity: Parasitic fungi and saprobes, which are always found in combination with certain host plants or on their remains (4); - Indicators of environmental change: fungi which were present only under certain conditions or incidentally on special hosts, or on their remains (31). - Indicators of invasive species: fungi growing on dung, like Sporormiella and various representatives of Sordariales (5). - Indicators of fire: fungi occurring on burnt plant remains like Neurospora (23, 31). Among the newly used NPP are various representatives of Zygnemataceae. These filamentous green algae are among the most common in fresh water. Most species of this cosmopolitan, but not ubiquitous group of algae occur in shallow, stagnant, clean, oxygen-rich waters (29). The characteristic spores allow the algae to overcome unfavourable conditions (e.g. drying out of pools). The analysis of cyanobacteria allows a better understanding of changing local environments in lakes and pools. Spores of Aphanizomenon and Anabaena (28) could be used as indicators of anthropogenic phosphorus enrichment in a lake catchment area. Surface samples of the muds in the eutrophicated Lake Fúquene (Colombian Andes) contained enormous quantities of Anabaena spores (observation van Geel). From studies in South and Central America (6, 10, 24) and Africa (Lake Challa, Kenya; van Geel, in prep.) it is evident that the analysis of NPP is very useful in palaeo-environmental reconstructions worldwide, among others when reconstructing human impact.

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Open Programme Comparison of evidence from natural vs. historical archives may fuel understanding of: - introduction of plant species vs. the pollen-based record of plant introductions (65, 71, 73, 76) - written deforestation history vs. pollen-based deforestation record (AP/NAP ratio) - written fire history vs. charcoal-based fire record in the sediment archive - storm and cyclone events vs. energy level and sediment input of marine incursions at site TAT (64). Most promising is a comparison over some 200 years between (a) the instrumental record of weather conditions, droughts in particular, (b) the record of sugar cane production (drought sensitive), and (c) proxy records from our sediment cores reflecting droughts. Reconstruction of change at continental scale – Relevant records of past environmental and climate change in and around the Indian Ocean are available from e.g. Madagascar (43, 46, 51, 52, 75), and Eastern Africa (e.g. 20). A comparison between observed climate change in the Indian Ocean/East African area (56), and across the tropical Atlantic Ocean (2) would further improve understanding of mechanisms at work in the global climate system (40, 55, 60). The periodic migration of the precessiondriven Intertropical Convergence Zone (ITCZ), and submillennial-scale variability possibly related to mega-ENSO (48, 57, 64, 66), are expected to have significant impact on Mauritius’ ecosystems. SCIENTIFIC ORIGINALITY – The proposed research is original in various aspects: - deposits in volcanic craters offer rare possibilities to obtain long and continuous records over full cycles of climate change (glacial vs. interglacial; precession-driven wet vs. dry); - for the first time long terrestrial records from the Southern Indian Ocean outside Madagascar are studied improving paleodata-model comparisons (19) in this ‘empty’ part of the globe; - we can monitor effects of sea-level rise (site TAT) on coastal ecosystems (increasing brackish/marine environments); the frequency of minerogenic layers (high-energy flow sheets) in the sediment record of TAT potentially reflect an unprecedented Holocene record of discrete storm events, possibly related to ENSO climate variability; - the natural pre-1600 AD setting is obtained from lowland and montane sites allowing to produce a high quality baseline study allowing new governmental and NGO-based management and restoration activities (59, 76) including the conservation of biodiversity; - a pollen-based record of exotic plant introductions is cross-checked to the available very complete historical record (65, 71); - from a paleoe-ecological perspective we will further elaborate on hypotheses how Mauritius reached its high biodiversity status by evaluating the role of riverine gallery forest as a refugium; the intriguing parallel of the high Andean archipelago of paramo islands (15) will be used. REFERENCES 38 Absy, ML, Cleef, AM et al., 1991. Mise en évidence de quatre phases d’ouverture de la foret dense dans le sud-est de l’Amazonie au cours de 60,000 dernieres années. C.R. Ac. Sci. Paris 313, 673-678. 39 Azizi, G, Flenley, JR, 2008. The last glacial maximum climatic conditions on Easter Island. Quat. Intern. 184, 166-176. 40 Batterbee, RW, Gasse F., Stickley, C, 2004. Past climate variability through Europe and Africa. Springer, Dordrecht, The Netherlands, 638 pp. 41 Behling, H, Bush, M, Hooghiemstra, H, in press. Biotic development of Quaternary Amazonia: a palynological perspective. In: Hoorn, C. et al. (eds.), Neogene history of Western Amazonia and its significance for modern biodiversity. Springer. 42 Biber, E., 2002. Patterns of endemic extinctions of island bird species. Ecography 25, 661-676. 43 Burney, DA, 1993. Late Holocene environmental changes in arid SW Madagascar. Quat. Res. 40, 98-106. 44 Burney, DA, 1997. Tropical islands as paleoecological laboratories: gauging the consequences of human arrival. Human Ecology 25, 437-457. 45 Bush, M, Colinvaux PA, Wiemann, MC, Piperno, DR, Liu, KB, 1990. Late Pleistocene temperature depression and vegetation change in Ecuadorian Amazonia. Quat. Res. 34, 330-345.

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Open Programme 46 Cheke A 1987. An ecological history of the Mascarene Islands, with special reference to extinctions and introductions of land vertebrates. In: Studies of Mascarene Island birds. Diamond, A.W. (ed.), Cambridge University Press, pp. 5-89. 47 Dearing J A, Battarbee R W, Dikau R, Larocque I, Oldfield F. 2006. Human-environment interactions: learning from the past. Regional Environmental Change 6, 1–16. 48 DeVries, TJ, Ortlieb, L, Diaz, A, Wells, L, Hillaire-Marcel, C, 1997. Detrmining the early history of El Niño. Science 276, 965-966 49 Ellis, EC, Ramankutty, N, 2008. Putting people in the map: anthropogenic biomes of the world. Front. Ecol. Environm. 6: doi: 10.1890/070062. 50 Gasse, F, 2000. Hydrological changes in the African tropics since the Last Glacial Maximum. Quat. Sci. Rev. 19, 189-211. 51 Gasse, F, Van Campo, E, 2001. Late Quaternary environmental changes from a pollen and diatom record in the southern tropics, Madagascar, Palaeo3 167, 287-308. 52 Gasse, F, Van Campo, E, 1998. A 40,000-yr pollen and diatom record from Lake Tritivakely, Madagascar, in the southern tropics. Quat. Res. 49, 299-311. 53 Haug, GH, Hughen, KA et al., 2001. Southward migration of the intertropical convergence zone through the Holocene. Science 293, 1304-1308. 54 Hoorn, C., 2006. The birth of the mighty Amazon. Scientific American May 2006, 40-47. 55 Leroux, M, 2001. The meteorology and climate of tropical Africa. Springer, Berlin, 548 pp. 56 Marchant, R et al. 2006. The Indian Ocean dipole – the unsung driver of climatic variability in East Africa. Afr. J. Ecol. 45, 4-16. 57 Martin, L., Fournier, M. et al., 1993. Southern Oscillation signal in South American palaeoclimatic data of the last 7000 years. Quat. Res. 39, 338-346. 58 Martin, L, Bertaux, J, Correge, T et al., 1997. Astronomical forcing of contrasting rainfall changes in tropical South America between 12,400 and 8800 cal yr BP. Quat. Res. 47, 117-122. 59 Mayle, F, Langstroth, RP, Fisher, RA, Meir, P, 2007. Long-term forest-savannah dynamics in the Bolivian Amazon: implications for conservation. Phil. Trans. R. Soc. Lond. B 362, 291-307. 60 McGregor, GR, Nieuwolt, S, 1998. Tropical climatology, 2nd ed. Wiley, 339 pp. 61 Nicholls,H., 2006 . Digging for dodo. Nature 443, 138-140. 62 Odada, E, Olago, D., 2005. Holocene climatic, hydrological and environmental oscillations in the tropics with special reference to Africa. In: Low, PS (ed.), Climate Change and Africa, pp. 3-22. Cambridge U.P., UK. 63 Resource Atlas for Mauritius and Rodrigues, 2007. Editions Le Printemps, Mauritius, 49 pages. 64 Riedinger, MA, Steinitz-Kannan, M, Last, WM, Brenner, M, 2002. A 6100 14C yr record of El Niño activity from the Galapagos Islands. J. Paleolimn 27, 1-7. 65 Rouilland, G, Guého, J, 2003. Les plantes et leur histoire a l’ile Maurice. MSM Ltd., 752 pp. 66 Sandweiss, DH, Maasch, KA, Burger, RL et al., 2001. Variation in Holocene El Nino frequencies: climate records and cultural consequences in ancient Peru. Geology 29, 603-606. 67 Steadman D.W., Martin P.S., 2003. The late Quaternary extinction and future resurrection of birds on Pacific islands. Earth-Sci. Rev. 61, 133–147. 68 Straka, H et al., 1964-1989. Palynologia Madagassica et Mascarenica. Pollen et Spores and Tropische und Subtropische Pflanzenwelt. (the complete series of publications is available). 69 Stute, M. et al., 1995. Cooling of tropical Brazil (5°C) during the Last Glacial Maximum. Science 269, 379383. 70 Umer, M, Lamb, HF et al., 2007. Late Pleistocene and Holocene vegetation history of the Bale Mountains, Ethiopia. Quat. Sci. Rev. 26, 2229-2246. 71 Van Leeuwen, J, Schäfer, H, van der Knaap, WO et al., 2005. Native or introduced? Fossil pollen and spores may say. An example from the Azores Islands. NEOBIOTA 6, 27-34. 72 Vaughan, RE, Wiehe, PO. Studies on the vegetation of Mauritius: I. A preliminary survey of the plant communities. J. Ecol. 25, 289-343. 73 Webb, DA, 1985. What are the criteria for presuming native status? Watsonia 15, 231-236. 74 White, F, 1983. The vegetation of Africa, UNESCO, Paris, 356 pp. 75 Williamsen, D et al., 1998. Mineral-magnetic proxies of erosion/oxidation cycles in tropical maar-lake sediments (Lake Tritri Madagascar): paleoenvironmental implications. Earth Planet. Sci. Let. 155, 205-219. 76 Willis, KJ, Gillson, L, Brncic, TM, Figueroa-Rangel, BL, 2005. Providing baselines for biodiversity measurement. Trends Ecol. Evol. 20, 107-108. 77 Whittaker, RJ et al., 2008. A general dynamic theory of oceanic islands biogeography. J. Biogeogr. 35, 977994.

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Open Programme 78. Blaauw, M., Heuvelink, G.B.M., Mauquoy, D., van der Plicht, J. and van Geel, B., 2003. A numerical approach to 14C wiggle-match dating of organic deposits: best fits and confidence intervals. Quat. Sci. Rev. 22: 1485-1500. (79) Hannah, L et al. 2008. Climate change adaptation for conservation in Madagascar. Biol. Lett. 4, 590-594.

5. Timetable of the project and working programme: month 1-6: familiarization with Mauritius setting, 3-weeks field work (coring, herbarium work, recent pollen rain; water and diatom samples), preparation of pollen and diatom samples, 14C dating month 7-18: analysis of pollen, NPP plant macrofossils, grain size analysis, 14C dating, (obligatory) courses Graduate School (we will search for a master student to support the PhD student) month 19-24: paper-1 (reconstruction based on Kanaka Crater), analysis of pollen, NPP plant macrofossils, diatoms, grain size analysis month 25-30: analysis of pollen, plant macrofossils, NPP, diatoms, grain size analysis, (obligatory) courses Graduate School School (a second master student will be involved) month 31-36: paper-2 (reconstruction based on Grand Bassin), analysis of pollen, NPP plant macrofossils, diatoms, grain size analysis, participation in INQUA-2011 Congress month 37-42: completing analysis of pollen, NPP plant macrofossils, diatoms, grain size analysis; paper-3 (reconstruction based on coastal sites TAT & MAS) month 43-48: paper-4 (baseline study; synthesis of Mauritius dynamic environments; elaboration of hypothesis on the role of riverine galley forest as a refugium; comparison with continental sites), paper-5 (history of site MAS from pollen and plant macrofissils in collaboration with other participants of the DRP working on wood, taphonomy of fossils, elemental geochemistry, and molecular palaeobotany). Preparation of thesis.

6. Affiliation with (inter)national research programmes (This should include an explicit description of existing and planned cooperation) This proposed project is part of the Dodo Research Programme (National History Museum Leiden, Institute for Biodiversity and Ecosystem Dynamics, Dutch Geological Survey / TNO / Deltares, Mauritius Heritage Fund, Mauritius Museum Council). Results will serve in the international initiatives PAGES (Past Global Change), DIVERSITAS (International Programme of Biodiversity Science). Data are made free accessible in the African Pollen Database (APD). We expect the results of this project allow important cross-links with the ongoing EU-funded KITE research project of dr R. Marchant (York University, UK); joint papers are envisaged. 7. Societal significance The dodo is globally known as the icon for human induced extinction. Reconstruction of the environment of the Dodo and the conditions under which this flightless bird went extinct supports Mauritius’ identity (the Dodo is in the coat of arms of the country and in currency) and tourist industry. The envisaged baseline study shows the natural conditions before human arrival: results form a blue print for nature restoration at selected places. Results will serve integrative projects to improve biodiversity and ecosystem services in agricultural landscapes (agroBIODIVERSITY network). First initiatives have been arranged (dr V. Tullaq, dr A. Janoo) to develop a student course on palaeo-ecological issues; these aspects are virtually unknown in Mauritius. In addition this study will contribute to the rationale to obtain a UNESCO World Heritage status of Mare aux Songes.

8. Legal requirements

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Open Programme Has been complied with the law and legal requirements with respect to the proposed Research, such as ‘Wet op Dierproeven’ and ‘DNA-recombinant legislation? Import of sediment cores will follow the rules of the Dutch Plant Health Services. x Yes Ο No 9a. Requested budget from ALW

Personnel (mm) Research costs (k€) Radiocarbon dates Grain size, diatom analysis Equipment Consumables*

2009 5 months 10

2010 12 months 10 6

2011 12 months 10 6

2012 12 months 10 6

4

4

2

3kE (corer) 2kE (computer) Fieldwork 5 kE * max. € 10.000,- p/year

2013 7 months

2

9b. Explanation and/or remarks to the proposed budget: - computer: 2 kEuro - 4 cores with each 9 AMS 14C samples = 36 x 500 euro = 18 kE - preparation 500 samples carbon content (LOI), 300 samples grain size analysis, 200 samples diatoms (external via dr. Velez) : 10 kE - extension of coring equipment up to 20 m deep & construction of special wide-blade Russian corer for soft sediments in Kanaka Crater > 3 kEuro - 1 x field work period of 3 weeks, including daily transport, air freight of samples, Plant Health Service costs > 5 kEuro. A short field work period is planned to strengthen interpretations. 10. Financial assistance from (an)other source(s) During field work the Institut Mauricien de Recherches Sucrières (MSIRI) will continue its support (transport, herbarium). NATURALIS supports public relations. Sample preparation is supported by the research group of Hooghiemstra (pollen & macro ~ 20k€, LOI ~ 4k€, software 3k€, scannen Straka collection 2k€). 11. Relation research program university, large institutions, research schools, etc. Research is a part of the Institute for Biodiversity and Ecosystem Dynamics (IBED; theme 3 ‘Ecosystem dynamics’), and of the Graduate School InterUniversitary Centre for Geo-ecological Research (ICG; theme ‘Palaeo-ecology and Palaeoclimatology of the Quaternary’). Research follows logically from the long standing research programme of the Research Group ‘Paleo-ecology and Landscape Ecology’, and the specific expertise on human impact studies (dr. B. van Geel) and paleo-ecology and climate change of the tropics (prof. H. Hooghiemstra).

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