Pollen Analytical Data Research Articles

The late Pleistocene and Holocene in the Lourdes Basin, Western Pyr�n�es, France: new pollen analytical and chronological data

In the Lourdes Basin, pollen analytical results and 41 14C dates from three sites (four profiles, 538 spectra) have enabled a coherent biostratigraphy to be established from the last Pleniglacial to the present. The end of the Wurm Pleniglacial is characterised by a long phase dominated by Poaceae that extended from ca. 20 000 to ca. 15 000 B.P. Another phase with Poaceae, in the context of a treeless environment, is recorded during the late-glacial between the Juniperus optimum (ca. 13 000 B.P.) and the Betula optimum (after ca. 12 500 B.P.). A marked decline in Betula and a rise in Artemisia values suggest a significant cooling of the climate during the Younger Dryas, an event which is now clearly recorded at several sites in southern Europe. The beginning of the Holocene is characterized by the minor role of Pinus and the early arrival of Quercus which achieves an absolute maximum before the arrival of Ulmus and Corylus. A critical assessment of previously published data is made in the light of these new results.

Efficacité de l'analyse mélitopalynologique quantitative pour la certification des origines géographique et botanique des miels: le modèle des miels corses

A new method to process pollen data derived from honey has been developed. During a three-year study 112 honey samples were collected and representatives of the different region of the island have thus been analysed. Presentation of the results in diagrams appeared to be more precise and more easily readible than the usual tables of frequency classes. This also facilitates comparisons between samples and enables a direct analysis of the relative frequency distributions of the taxa studied. However, apart from the graphic presentation, the main methodological advantage of the Melisoft software is the automatic comparison of the pollen content of the honeys. It permits without referring to any previous classification, to characterize honeys on the basis of their relative pollen-frequency spectra and taking into account the presence/absence parameter. The method is a variance analysis with a sorting function which enables one to compare and place each sample with respect to the 111 other samples while incorporating the totality of the taxa database. The classification obtained is valuable; it shows that pollen analysis in the determination of the botanical origin of honeys is not only of accessory but also of fundamental importance. The following honeys could thus be characterized: chestnut ( Castanea sativa) honeys, more complex and composite maquis honeys with dominant tree heath ( Erica arborea), honeys from plains or coastal Cistus areas, sour orange ( Citrus aurantium x deliciosa) honeys, strawberry tree ( Arbutus unedo) and asphodel ( Asphodelus microcarpus) honeys. The interest and limitations of the method are discussed, taking into account the “secondary and tertiary enrichments” in pollen of plants with no nectary as well as the over- or under-representation in honeys of pollen from the main nectariferous flowers. The presence of “indicators” such as Anthyllis hermanniae and Cytinus hypocistis as well as assemblages of biogeographically different taxa shows that it is possible to certify the Corsican origin of honeys. This method of treating pollen analytical data can also be applied to characterize botanical and geographical origins of honeys of other regions or countries.

Quantitative climate reconstruction from pollen data in the Grand Duchy of Luxembourg since 15 000 yr BP

AbstractMonthly temperature and precipitation estimates for the period 15000–2000 yr BP are statistically derived from pollen analytical data obtained from a site near Echternach, Luxembourg. A continuous warming trend of over 10°C is recorded for the period 10500—8000 yr BP, along with a rise in precipitation of 500 mm. A fairly constant temperature characterised the period between 8000 and 2000 yr BP, though an episode of slight temperature decrease (‐2°C) occurred at about 4500 yr BP. The most humid intervals seem to have been at around 9000–7000 and 5000–3000 yr BP (principally during the warm season: more continental influence). In contrast with results obtained from more southerly sites, the ‘Older Dryas’ climatic reversal is clearly recorded at Echternach slightly before 12000 yr BP. It is marked by a cooling in July temperature of about 4°C and a decrease in monthly precipitation of about 30 mm (40%).

The ecological significance of sclerophyllous oak forests in the western part of the Mediterranean basin: a note on pollen analytical data

The ecological significance of sclerophyllous oak forests in the western part of the Mediterranean basin: a note on pollen analytical data

Occurrence of larch (Larix) in Fennoscandia during the Eemian interglacial and the Brørup interstadial according to pollen analytical data

The occurrence of pollen and macrofossils of larch in Eemian deposits in northern Finland indicates that this species must have grown in the area during the last interglacial. Lark spread to Finland from the east, its date of arrival being deducible from the general vegetational succession. It probably did not grow in central or southern Finland during the interglacial, but is thought to have extended fairly far south in Sweden and Noway along the Fennoscandian mountain range. The Lark pollen found at the upper boundary of the interglacial deposits at Margreteberg and Stenberget in southern Sweden may suggest that it did reach southern Sweden by the very end of the Eemian, but it cannot be said for certain whethcr this pollen represents an influx of Larix from the north or from Central Europe.

Pollen analysis of late quaternary sediments: Evolution of upland savanna in Sandynallah (Nilgiris, South India)

The evolution of upland swampy savanna with luxuriant herbaceous cover in Sandynallah, in the Nilgiri hills of southern India, from the initial swampy or per-humid stage through humid, semi-humid and arid phases of dense, sparse to poor herbaceous vegetation respectively, is inferred from the pollen analytical data. The present study does not support the view that the swampy grass formations were a secondary development of degraded shola forests. The evidence presented in this paper supports a view that montane grasslands persisted in the area since ca. 30,000 yr B.P. It is probable that frost and soil factors have been the important determinants in maintaining and stabilizing the swampy upland savanna of Sandynallah since ca. 2500 yr B.P.

The 14C dates and 13C/ 12C ratios of soil organic matter as a means of studying the past vegetation in intertropical regions: Examples from Colombia (South America)

The 14C ages and 13C/ 12C values were obtained on soil-organic matter of various soils sampled in the Guasca Valley adjacent to the high plain of the Sabana de Bogota, in the Colombian Cordillera Oriental. A soil distribution is observed as a function of climatic and altitudinal changes: in the lowest parts of the valley, planosols are found from the bottom of the valley to 2700–2800 m. At altitudes up to 2900 m, brunizems and ferrisols occur. Above 3000 m andic soils are almost everywhere present in more humid mountain zones. At present, the landscape is widely open, without any natural forest. Nevertheless, it was proved by pollen-analytical data that at altitudes up to 3000 m the Andean forest replaced a paramo formation 13,000 yr ago. To conciliate the facts with the known evolution of the vegetal population, a first hypothesis consists of admitting that open landscapes were due to a recent anthropogenic destruction of the forest. The forest-degradation hypothesis was tested by determination of the 13C/ 12C ratio because the trees have a δ 13C of −25% to −28% (influence of plants with C 3 photosynthesis pathway), whereas herbs characteristic of open vegetation, such as tropical grasses, may have a δ 13C of −23% to −16% (due to a C 4 photosynthetic cycle). The organic matter dated at 13,000–30,000 yr has δ 13C close to −25% in the andic soil zone. This indicates that at elevations of around 3000 m a cold paramo vegetation was probable. For organic matter dated at 12,000-6000 yr, δ 13C shows a variation from −23 to −21% that does not indicate forest conditions. It is uncertain that a forest stage occurred in the past. For the planosols, brunizem and ferrisol, organic matter dated at 13,000–20,000 yr has a δ 13C (−23%) compatible with the paramo vegetational phase occurring at that time. For organic matter dated at 9500 yr and less, δ 13C varies from −20% to −17%. These values do not confirm the evidence of forest conditions but rather the existence of open vegetation typified by a mixture of C 3 plants (shrubs and rare trees) and tropical Graminaea. Thus, the 13C values prove that the valley has known drier and warmer influences that prevented the forest from developing during the Holocene. To explain the origin of the open landscapes of the valley, the hypothesis of recent human deforestation must be discarded. Moreover, the valley appears as a persistent dry enclave in the oriental Cordillera.

福島県南部・矢の原湿原堆積物の花粉分析による最終氷期の植生変遷

This paper describes the palynological study of a core from Yanohara Bog, Fukushima Prefecture, northeastern Japan. Four marker tephras laid down during the Last Glacial Period are recognized in the core: Pm-1, Aso-4, DKP, and AT.The pollen diagram obtained is divided into five pollen zones. The ages of the boundaries between the pollen zones are calculated from the depositional rate of the marker tephra. YH-I (about 8-5.7m.y.B.P.) corresponds to the early Last Glacial Age. Both YH-IIa (about 5.7-5.0m.y.B.P.) and YH-IV(2.6-1.4m.y.B.P.) correspond to cold stages. YH-V corresponds the Holocene.It is clear that there were two cold stages and one relatively warm stage during the Last Glacial Period. From pollen analytical data, it is found that the earlier cold stage(YH-IIa) was colder to than the later stage(YH-IV).

Pollen analysis and quaternary research in Scotland

The development of pollen analysis in Scotland and its role in present-day Quaternary studies are examined. Methodological advances in field and laboratory techniques, in the treatment and interpretation of pollen analytical data and in palaeoecological investigations involving pollen analysis are considered in the context of research in Scotland. The applications of pollen analysis in specific areas of Scottish Quaternary research are then discussed. These include the reconstruction of interglacial, interstadial and Late Devensian Lateglacial environments, Flandrian plant migrations and forest history, man and landscape change in the mid- and late Flandrian, the dating of geomorphological events, and the study of land and sea-level changes.

A re-evaluated glacial chronology for northern East Greenland

Abstract The combination of geomorphological, lithostratigraphical and pollen-analytical data from southern Hochstetter Forland and Shannon ø. northern East Greenland, together with 14 C datings and a time/temperature evaluation of amino-acid racemization data, leads to a re-evaluation of the glacial chronology of that area. The most extensive Weichselian glaciation probably culminated not long before 15 000 BP, during the Nanok I stadial. This was a fairly limited glacial advance, compared to older recognized stages represented by older sediments and more weathered landforms. During Nanok I sizeable ice-free lowland areas existed and there was a number of nunataks in the western mountains. Initial deglaciation of the southern rim of Hochstetter Forland took place well before 13000 BP, during the Artemisia interstadial characterized by a pioneer type vegetation. At ca. 10 100 BP the glaciers advanced again, reaching almost the same frontal positions as during Nanok I time. This stadial, Nanok II, ended with the final deglaciation beginning ca. 9500 BP. Nanok II time is characterized by barren interzones in the pollen diagrams. A pioneer type vegetation, similar to that during the Artemisia interstadial, reappeared after 9500 BP and was not succeeded by a true ‘postglacial’ vegetation until ca. 8200 BP. Time/temperature evaluation of amino-acid racemization in mollusc shells from the Peters Bugt marine sediments, immediately underlying the Nanok I moraine, suggests that these sediments date from around the last (Eemian) interglacial. This view is supported by a distinct weathering break at the outer edge of the Nanok moraines. Thus, contrary to earlier interpretations, there would seem to have been no Early or Middle Weichselian glacial advances of any consequence in these parts of Northeast Greenland. Data suggest that the older recognized stages of glacial advance, the Muschelbjerg- and Kap Mackenzie ‘stadials’, were of Saale and older age and that the Weichselian maximum in this high arctic area roughly correlates in time, but not at all in relative amplitude, with the classical Weichselian (and Wisconsinan) maxima around 18000 BP.

Palynological evidence for lake-level changes during the Flandrian in Scotland

Summary Stratigraphic, relative pollen analytical data and pollen concentration data are presented from two cores collected from a lowland infilled lake basin in the eastern Scottish Borderlands. The stratigraphic sequence between 1·30 m and 2·16 m shows an oscillation of open water and deep water sediments indicating lake-level changes. This is supported by the pollen analytical data which show a markedly changing pollen sedimentation rate and a hiatus in Flandrian II due to changing lake-levels and an overall reduction in water-level. Supporting evidence is also drawn from Din Moss, a nearby radiocarbon dated profile.

A pollen diagram from Pitbladdo, Fife

Summary Pollen analytical data are presented from a site near Cupar, Fife. The stratigraphy and pollen spectra are used to infer the changing patterns of vegetation in the area during the Lateglacial and Postglacial periods. In the Lateglacial Interstadial the local development of Betula-Juniperus scrub was followed by a period of open habitat during the colder Loch Lomond Stadial. The early Postglacial forest was dominated by Corylus and Betula, although Ulmus was also a major woodland component before the arrival of Alnus. Following some initial deforestation due to anthropogenic activity, subsequent woodland clearance was almost total and open habitat communities dominated.

Some Applications of the Independent Treatment of Taxa in Pollen Analysis

The paper explores the utility of a technique for interpreting pollen analytical data by the separate statistical treatment of each taxon. Three sets of published data are partially re-interpreted by the method. Amongst other attributes, it clearly displays the degree of synchroneity in changes between taxa and describes each section of a pollen curve in statistical terms which may allow of ecological interpretation.

Contemporary 14C Levels and Their Significance to Sedimentary History of Bega Swamp, New South Wales

Atmospheric 14C variations in nature, as previously documented for the Southern Hemisphere by studies carried out in South Africa and New Zealand, were supplemented by 14C concentration measurements of wheat-grain samples collected in southeastern New South Wales. Our measurements cover the critical period of 1945/46 up to 1956/57, and span the transition of Suess and atom-bomb effects. The observed variations can be followed quite precisely in the peat deposits of the Bega Swamp, New South Wales, and indicate that vertical mixing of organic components within the peat is negligible. Pollen analytical data covering the last 400 years also show that the peats act as efficient traps; thus, time-precise zonations can be identified, and historically documented man-induced changes in pollen assemblages can be correlated with 14C ages in recent times.

Late Quaternary vegetational history of the Enga province of Upland Papua New Guinea

Late Quaternary vegetational history of the Enga province of Upland Papua New Guinea

La formation d'Herzeele : un nouveau stratotype du Pléistocène moyen marin de la mer du Nord

The Herzeele Brickyard (Northern France) offers a permanently well exposed outcrop of continental and marine deposits which are reaching a total thickness of 6 m and are overlying the Ypresian clay of eocene age, occuring at about 8 m N.G.F. Three marine phases represented by tidal flat and brackish sediments may be readily distinguished. The tidal flat sediments have previously been recognized in the area of Izenberge (Belgium) from which locality the name "Izenberge Cardium Sands" has been derived. The marine sediments may be subdivised into units of different lithology : the lower sandy unit, the middle loamy-clayey unit and the upper sandy clayey unit which latter is characterized by the abundance of Cardium edule and Macoma balthica. The marine phases are furthermore separated by continental deposits amongst which peat layers are occurring. The cover sediments are represented by eolian sands and loams interfering with palaeosoils. The series of sediments underlying these cover deposits is named the "Herzeele Formation" which represents a hthostratigraphical unit in the southern North Sea basin. The analysis of the heavy mineral content points to a change in sediment origin occuring after the lower marine sedimentation. The middle and upper marine units contain an increasing content of green hornblende and epidote. Some volcanic minerals were observed at different levels. The clay analyses by means of X-ray diffraction indicate that the different lithostratigraphical units bear polymineralic clay assemblages within which the smectitic fraction is predominant. Greene-Kelly's (1953) Li-test yielded a further detailed analysis of the smectitic components : beidellite, montmorillonite-like minerals as well as random mixed-layers illite-smectites. The analysis indicates a stratigraphical - mineralogical subdivision of the section which coincides with the lithostratigraphical one. The pollenanalytical data show that the whole of the Herzeele Formation most probably belongs to the second half of the Holsteinian interglacial, except for the very base composed of glauconiferous sands. It may readily be seen that the forest evolved from a mesocratic phase, characterized by a Quercetum mixtum with Picea, towards a telocratic phase dunng which the forest became dominated by Abies. Within the peat which is resting upon the glauconiferous sands, the pollen grains of Taxus, are very abundant in the overlying clay however, this species declines gradually and disappears at the top of the upper marine unit. These evidences are corresponding with the first half of the so-called Abies- zone. Buxus and Vitis, both undergo the same evolution. The only Tertiary relict, Pterocarya, made a short appearance at the top of the upper manne unit, while Azolla filicubides, was only discovered in the Quercetum zone. The diatom analyses indicate the conditions of brackish and marine sedimentation in a tidal environment. Although the magnetostratigraphical approach of deep-sea and lake sediments has proven to be successful, its application to continental and especially coastal sediments is hampered by the very nature of these sediments (large variation of sedimentation rate, depositional environment, lithology, a.o.) The palaeomagnetical study of the Herzeele Formation reveals a striking difference in magnetic behaviour between the upper and lower beds separated by the lowermost peat layer. The upper beds are characterized by a strong dispersion of the magnetisation directions and a low intensity. Therefore identification of clear-cut magnetozone(s) is not possible for the moment being. As to the extension of the Herzeele Formation in Belgium, it was only found south of the river Yzer. The comparison with the area of Izenberge itself did not reveal any lithostratigraphical correlation with the Herzeele Formation. The situation of the stratum (former shoreline) at this type-locality gives prove of the importance of the palaeographical evolution since the Lower Pleistocene with the formation of the southern North Sea basin and probably the early opening of the Strait of Dover as well. Therefore this stratum is considered as a landmark and a witness of several interglacial marine transgressions which are attributed to the Holsteinian and to the upper part of the "Cromerian complex".

AN ALGOL-60 PROGRAM FOR POLLEN ANALYTICAL DATA; THE CDC VERSION

SUMMARY This paper describes the CDC version of a formerly published computer program for the computation and graphical representation of pollen analytical data.

AN ALGOL-60 PROGRAM FOR COMPUTATION AND GRAPHICAL REPRESENTATION OF POLLEN ANALYTICAL DATA

This paper describes an ALGOL-60 computer program for computation and graphical representation of pollen analytical data. The program offers the possibility of computing and drawing relative frequencies, values per unit of sediment and values per unit of sediment per unit of time. An input description is included.

Old Peat Layers occured in the Ozegahara Basin

The Ozegahara Basin is a typical sphagnum-moor, which is situated in Central Japan about 1400 meters above the sea level. Among plants growing in the moor are found many species which are inferred the relic of the last ice age. This basin was born in younger Pleistocene because of damming up the ancient valley of the River Tadami by the lavas from the Hiuchidake Volcano (2346m). At the northeastern corner of the moor are found the peat layers alternating detritus overlaid the deposits of mudflow from Hiuchidake. Stratigraphically these peat layers are correlated to uppermost Pleistocene. According to the pollen analytical data, pollen grains of conifer are predominant through the layers and reversely Fagus pollen grain is very few or partly not in the samples, while the present moor is surrounded by Fagus forest and pollen spectrum from the surface sample of the moor reflects this state. From these results it may be concluded that the temperature of this area at that time was 1-2°C lower than the present day.

POLLEN ANALYTICAL INVESTIGATIONS IN THE NORTHERN NETHERLANDS WITH SPECIAL REFERENCE TO ARCHAEOLOGY

For many years already there has been a close co-operation between archaeology and palynology. This co-operation is particularly concerned with the investigation of archaeological objects—sometimes even complete settlements—which were discovered in the peat. With the help of archaeologically well datable finds it was possible to obtain a dating of some parts of the pollen diagram and of stratigraphical phenomena as the recurrence surfaces in the Swedish raised bogs. Next, objects which were archaeologically not datable, viz. trackways and peat burials, could be dated more or less accurately by means of pollen analysis. In the last few years, moreover, attention has been paid to the pollen analytical investigation of samples from burial monuments. It was WATERBOLK who worked out this method, and who attained important results. In this investigation much stress is laid on the correlation between archaeological and scientific phenomena. In this connection it was in the first place of much importance to have the disposal of a detailed diagram from a large raised bog whose pollen content cannot have been influenced to a great extent by local conditions. From this diagram reflecting the vegetation development in a given region alterations of the vegetation effected by climatic changes or human interference can be read. Moreover, by means of such a diagram other pollen analytical data from that given region—which have often been influenced by local conditions—can be compared better with those from other regions.