The Study of Palynology
Palynology can be simply defined as the study of dust or strewn particles. A more detailed definition of palynology will define palynology as the scientific field concerned with the analysis of pollen and spores from plants, and minuscule planktonic entities (collectively known as palynomorphs), both alive and in fossil form. Palynologists are individuals who study palynology. A palynologist typically analyses samples collected from everywhere in the environment such as the air, water, or even from sediments from any period. From this study, a classic palynologist can determine the condition and be able to identify these particles, as well as gain clues regarding the environment, life, and the energetic surroundings that formed these particles.
At times, the term is loosely used to refer to a subdivision of the discipline. This subdivision can be explained as the study of microscopic objects of organic composition that is of a macromolecular nature, that is, objects that are incapable of dissolving in hydrochloric or hydrofluoric acids such as the compounds of hydrogen, oxygen, carbon, and nitrogen. This science is on that is involved with the analysis of fossil and contemporary palynomorphs such as spores, dinocysts, chitinozoans, and others, jointly with particulate organic matter (POM) and kerogen in sediments and sedimentary rocks. However, it is important to note that palynology does not include the likes of diatoms, foraminiferans, or other entities that have calcareous or siliceous carcasses.
From the above, it is reasonable to conclude that palynology is a field of science that is interdisciplinary and is a subdivision of geology (the study of the earth) and biology, with an emphasis on botany or the study of plants.
Methods Used In Studying Palynomorphs
A broad definition of palynomorphs would be an organic-walled microfossil that measures between 5 and 500 micrometers. These organisms are obtained from the sedimentary rocks and cores. This extraction can be done in either one of two ways; physically through wet sieving and ultrasonic treatment or chemically by dissolving the non-organic part only.
Palynomorphs are important because they help to preserve the geological record of the ancient life if any, that existed close to the region when the sedimentary rocks were formed. In addition to the geological record, they also help the expert to determine the prevailing climatic conditions of the region when the rock formation was laid down. Generally, most palynomorphs have been destroyed during the formation of metamorphic rocks.
Palynofacies refer to the total accumulation both palynomorphs and organic matter in a deposit of fossils. Palynofacies of a particular depositional ecosystem of sediments are useful while attempting to learn about depositional palaeoenvironments of the sedimentary rocks found in that ecosystem. The term palynofacies was first introduced to the academic world by a French geologist called André Combaz in the year 1964. Studies in this discipline are typically connected to the analysis of organic geochemistry of sedimentary rocks and palynology.
Palynofacies can be used in either one of two ways. Both of these ways are for a geological understanding of sedimentary basins. These ways are: (1) Palynofacies of the organic nature are involved with POM’s that are insoluble in acid with the inclusion of kerogen, palynomorphs found in sediments, and preparations of sedimentary rocks for palynology. These preparations may or may not be sieved and are then scrutinized using strew mounts on a microscope. Things to be considered during the scrutiny include the composition, abundance, and preservation of the components coupled with thermal changes of the organic substance. (2) Palynomorphic palynofacies scrutinize the composition, wealth, and how diverse palynomorphs are in a sieved preparation of sediments or sedimentary rocks. The ratio of marine fossils combined with chitinozoans to terrestrial palynomorphs is used to get the terrestrial input index of marine sediments.
In this type of preparation, a number of steps are followed. Formerly, researchers only used potassium hydroxide for treatment in order to eliminate humic material. Deflocculation was done by surface treatment or ultrasonic treatment. Ultrasonic treatment may cause the pollen exine to burst. Assarson and Granlund introduced the used of hydrofluoric acid to remove silicate minerals in the year 1924. The introduction of this acid in this discipline significantly reduced the time that researchers used to look for palynomorphs. The usage of peat in treatment presented a problem for researchers because of the presence of well-preserved organic substances. To remove this problem, a new method called acetolysis was introduced by Gunnar Erdtman and his brother. Acetolysis removed the problems because it dissolves these materials. Acetolysis uses sulfuric acid and acetic anhydride to remove cellulite substances to give the researcher improved visibility while analyzing palynomorphs.
Analysis of the samples is typically done in a lab on a microscopic slide. These slides may use glycerol, glycerol-jelly, or silicon oil which are then scrutinized using light or mounted for electron microscopy.
Palynology has a number of uses.
• Since palynomorphs resist decomposition and are produced in massive amounts, their analysis provides data about plant life and rocks thus help in locating layers of sedimentary rocks that may have natural gas or oil.
• Melissopalynology is the study pollen and spores in honey. Farmers use this information to determine proper pricing of their products and determining whether the pollen is safe for human consumption.
• Forensic palynology helps with studying the palynomorphs and pollen at a crime scene for evidence collection.
• Archaeological palynology is used by archaeologists to determine how the human species used plants in the past and thus determine the ways of life of past civilizations.
• Palynology may also help those who suffer from allergies through the study of pollen.
• Palynology is used in geothermal studied to give estimates of maximum palaeotemperatures. The discipline may also be used in limnology in order to uncover lake levels in the past as well as climate change.
• Palynology can also aid in biostratigraphy and geochronology, that is, determining the age of rocks.
• Entomapalynology refers to the examination of pollen located in the gut or the body of insects, which helps with ascertaining feeding and migratory habits of insects especially if the insects are economically significant.