Palynological Methods Research Articles

The environmental and climatic distribution of dinoflagellate cysts in modern marine sediments from regions in the North and South Atlantic Oceans and adjacent seas

Quantitative treatments of 168 dinoflagellate cyst assemblages from modern marine sediments were used to decipher the salient environmental and climatic features of the distribution of common living cyst-based taxa. Surface sediment samples were studied by routine palynological methods from estuarine, continental shelf, slope and rise zones, and abyssal plains between latitudes 62°N and 27°S within fourteen geographic regions of the North and South Atlantic Oceans, the Caribbean and Mediterranean Seas and from one region in the southeastern Pacific Ocean near Peru, to meet this general objective. The results were expressed as percentages of species present and statistically analyzed by multivariate Q-mode factor analysis, cluster analysis and by calculation of a diversity index, using pre-existing computerized routines. Inshore to offshore and latitudinal (climatic) variations in distribution were identified and they involved individual taxa, associations of species, species diversity and specimen densities (cysts per gram of sediment). They were related empirically to changing surface water environments above and this suggested that biologic-ecologic phenomena, which involve species-water type relationships for different taxa, combined with hydrodynamic (current) systems, are the most important factors that control cyst distribution in the bottom thanatocoenosis. However, geologic factors such as recycling of older specimens and outcroppings of relict Pleistocene-Early Holocene sediments exert their influence too. An ecologic classification for extant cyst-based species is proposed in the format of classical “plankton elements”. This format is dictated by the existence of dual trends (environmental and climatic) in cyst distribution. It is suggested that genesis of ecologic species-groups of this nature during evolution can be interpreted by or “predicted” from stability-predictability concepts as developed in contemporary ecologic work, if surface water masses are considered to represent unique hydrographic climates with innate stability and predictability characteristics. This concept of “hydroclimatic stability” is used to identify fossilizable living dinoflagellates as being environmentally adapted to unstable conditions around continental margins and comparable shallow-water environments around oceanic islands. In addition there is a tendency for the more stenotopic extant cyst-based taxa to be adaptively specialized towards more stable sectors of nearshore and offshore plankton environments which develop at the terminal and subterminal ends of temperature and salinity regimes or profiles. One taxonomic change is introduced: Planinosphaeridium choanum (Reid 1974) nov. comb. is proposed from the basionym Ataxiodinium choanum Reid 1974.

Palynology in Himalayan stratigraphy

The paper identifies some of the vexed stratigraphical problems and complex areas in the Himalaya where palynological method could be beneficially applied. Lack of reliable stratigraphic controls has been a major handicap in the recognition and assignation of time-stratigraphic equivalence to many rock sequences in Himalaya. The scope and potentiality of palynology as an effective and reliable tool to help and resolve various types of age and correlation problems in the Complex Himalayan set up is discussed.

Ecological Approach to the Prehistoric Man and Environment around the Lower Basin of the Abukuma River

The study of man-land relationships in prehistory requires good understandings of many aspects of the geographic environment of the past. Such an environmental reconstruction would be contributed by the geomorphological and palynological methods. This study aims to elucidate the history of man-land relationships in Neolithic period around the lower basin of the Abukuma River with these methods.Around the lower basin of the Abukuma, many shell mounds of Jômon age have been excavated. At the high sealevel period (B. P. 6, 000-5, 500yr.), the shoreline seems to have been retreated judging from the locations of these shell mounds. But the rate of submergence differed region to region with the local geomorphic elements. Regional differentiation of basic economic pattern of these shell mounds' people was mainly determined by micro-geomorphologic element around settlement site. After this high sealevel period, the sea gradually regressed. The micro-geomorphic environment around shell mounds changed from marine to lagoonal. Following such environmental change, the staple food of shell mounds' people changed from Meretrix lusoria to Corbicura japonica.The predominant vegetation of early Jômon age was deciduous broad leaved trees, especially Quercus and Ulmus. The climate of this period was warmer than present. In the broad leaved forest, Sus scrofa leucomystax, Cervus nippon nippon lived and these animals supplied important food resource for the specialized hunting people. On the other hand, prehistoric man gathered fruits and roots of plant in the forest. These impact of the prehistoric man destroyed the natural vegetation around settlement site. In the latter half of latest Jômon age (B. P. 2, 500yr.), the climate became cooler and wetter. At this period the predominant vegetation was Fagus and Cryptomeria. The author also studied animal ecology in relation to the change of vegetation and clarified the change of regional food resource of the prehistoric Man.

Zur Entwicklung eines montanen Quellmoores im Thüringer Wald und des Vegetationsmosaiks seiner Umgebung

Summary Using a combination of palynological and phytosociological methods, the stages of development of a spring fen in the central Thuringian mountains and of the surrounding mosaic of vegetation have been reconstructed. Around the 6th century a spring fen with dominant Carex rostrata took the place of a swampy spruce-alder-forest with Athyrium filix-femina. Until the 9/10th centuries beech forests were widely spread, but in the surroundings of the fen there were not only mixed deciduous woods with Tilia platyphyllos and Corylus avellana but also spruce stands on some small special places (nearly 900 m above sea level) according to the different expositions. During the 16th century the spring fen turned into a high moor rather quickly, and Picea abies began to penetrate the beech forests. Not only in the fen, but also in the surrounding mineral soils the nutritive substances became less and the acidity of the soil rose. The origin of the bog, the stages of its development, and the changes of the entire mosaic of the vegetation are only understandable by climatical and hydrological variation in this area. The change from the spring fen to the raised bog gives the first direct proof for the change of climate in the Thuringian mountains during the late middle ages; it caused the natural tendency of spreading of Picea abies and the origin of the altitudinal belt of spruce. This process was increased by anthropogenic influence. In the ridges the genesis of raw humus under spruce began around the 14th century.

Planation Surfaces in Guyana

Preliminary observations combined with information from members of the Geo? logical Survey of Guyana and other sources indicate that at least five erosion cycles with three major planation surfaces, or stepped erosion bevels, can be recognized in Guyana. These are interpreted as representing pediplains developed at successively lower levels during long periods of standstill which occurred during the periodic uplift of the Guiana Shield. These cyclical movements are correlated and dated by comparison with stratigraphic gaps in the Guyana coastal succession, as recently established by palynological methods, and with similar features in neighbouring sedimentarv basins. This content downloaded from 207.46.13.129 on Sat, 25 Jun 2016 05:14:42 UTC All use subject to http://about.jstor.org/terms PLANATION SURFACES IN GUYANA 5J9 The observed planation surfaces are as follows:

Present achievments in a palynological study of the Quaternary period in the USSR

Enormous palynological data are accumulated over the continental and marine deposits from the various regions of the USSR.
 Palynological data are usually applied together with the geological ones. At a time, diatoms and large plant remains are analysed. The absolute age determination by C 14 is in common use.
 The general pattern of distribution and dynamic of vegetation and natural zones in the Pleistocene and Holocene are traced in large scale regions and in all the country.
 Palynological data serve usually as a main criterion for the differentiation and subdivision of interglacials and interstadials with reference to their relative chronological estimates.
 Palynological method is used also for the identification of the Pliocene-Pleistocene and Pleistocene-Holocene boundaries, for the sub-division of deposits into horizons and zones on the base of vegetational changes, for the determination of past climates, for the typization of interglacial, interstadial and holocene diagrams with reference to their geographical position, time correlation, of marine transgressions etc.
 There are found some sections representing palynologically continuous vegetational development from the last interglacial to the present. The data from arid zone are very interesting to study pluvial and interpluvial periods.
 Palynological data show the extremely complicated development of the Pleistocene and Holocene vegetation, the significant mobility and transformation of natural zones.
 Only due to the use of palynological method it became possible to study climatic conditions, vegetational development and stratigraphical position of the Pleistocene and Holocene deposits.

Flözgleichstellung mit Hilfe palynologischer Untersuchungen im Saarkarbon

Flözgleichstellung mit Hilfe palynologischer Untersuchungen im Saarkarbon

Notes on Palynological Studies of Varved Sediments

ABSTRACT The writer suggests that the term varved should be restricted to laminated and graded sediments (both inorganic and organic) of annual, or seasonal (composed of a winter and a summer layer) origin where such nature can be established. He has shown by palynological methods the annual origin of varved clays in the Glacial Lake Barlow-Ojibway basin in northern Ontario, where a total of 2027 varves has been counted by Antevs (1925) and Hughes (1956). In this case the varve counts can be used as a time scale for certain events. Laminated sediments of other than annual origin and those resembling varves only in appearance should be clearly distinguished from the true varved sediments.

Applied Paleozoic Palynology: ABSTRACT

Delineation of specific segments of the Paleozoic geological column by palynological methods is based on the concept that plant composition throughout geological time underwent changes that are recorded in the recoverable spores and pollen grains. These changes are largely the result of plant evolution and paleoecology. The application of Paleozoic palynology originated 32 years ago with attempts to correlate economically important coals. In subsequent years, palynological data have been used in correlation studies of other strata, both non-marine and marine. Separate thresholds of guide fossils are required when plant microfossils from different environments are compared in attempting to establish correlation lines. The coal-swamp environment, at a given point in time, has a particular set of fossils not necessarily duplicated in other non-marine environments elsewhere. In recent years, palynological data have become available from many localities throughout the world. From these data it is possible to evaluate selected taxa potentially useful for correlation studies. Palynology has certain limitations inherent to the science and others common to biological methods of correlation. Although palynology can not be used in every correlation problem, it has been useful and practical for parts of the geological column, in some cases after other biological methods have failed to be definitive. End_of_Article - Last_Page 270------------

Palynology and Its Application in Petroleum Exploration: ABSTRACT

Palynology, the study of pollen and spores, is the only known universal method by which marine sediments can be correlated with fresh-water sediments. Study of the history of pollen analysis shows a rapid expansion in the use of this technique from 1916 onward. The Royal Dutch Shell Group initiated palynological studies in 1938, and many oil companies now have palynological laboratories. Pollen and spores can undoubtedly be preserved because the outer wall of the grains is extraordinarily resistant. The chemistry of this outer wall (exine) is unfortunately very poorly understood. Relation to terpenes or similar compounds has been suggested. Although exact information concerning the distribution of pollen and spores by wind is difficult to obtain, there is considerable evidence that they can be transported very great distances. Transportation by water is important, and examples of Recent studies in the Orinoco Delta, Volga River, and Gulf Coast are discussed. Pollen and spores can not withstand prolonged oxidation. The spore and pollen wall takes up oxygen (auto-oxidation). This photo-chemical process adds oxygen molecules to double linkages in the pollen and spore wall, with the formation of peroxides. Since oxygen is the main enemy of the spore and pollen wall, it is obvious that strata deposited in reducing environments commonly contain well preserved pollen and spores. Determination of ancient shorelines, age determination of Gulf Coast salt, and palynological correlations in Venezuela, Canada, and France are examples of practical applications of the palynological method. End_of_Article - Last_Page 1601------------