Has Quaternary palynology reached its climax?

Abstract

Throughout more than 100 years of its history palynology has become an independent discipline that is being applied in various fields from palaeoecology, aerobiology, forensic sciences to taxonomy. Bibliometric analysis allows to distinguish different phases in the evolution of palynology. From the initial phase, when the first pioneer results were released, through the building phase when the potential of pollen analysis has been expanding into new research areas, to mature phase in which palynology becomes a basic research method with worldwide recognition applied in many scientific fields. However, the scientometric analysis of palynological documents suggests that in the second decade of the 20th century, the increasing trend of the number of published documents stopped. This tendency has been observed in most of the journals publishing palynological content. This may suggest that the discipline has reached its climax. Moreover, the last couple of years show a slow but constant drop in the number of published documents. During this period also a decrease in mean citation per document and per year is observed. This poses a question – does this issue reflect only the state of the discipline or is that a wider phenomenon touching also other scientific fields related to palynology as for example palaeoecology? On the other hand, bibliometric analysis points out also some positive aspects of the evolution of palynology such as the increase in international co-authorship and the increase in the number of co-authors per document that indicates the development and specialization of the discipline.

Keywords

bibliometrics literature review palaeoecology palaeopalynology pollen analysis scientific trends

Introduction

The beginnings of palynology date back to the late 17th century and the works of Nehemiah Grew and Marcello Malpighi (de Klerk, 2018). However, it was Lennart von Post who brought pollen analysis in 1916 to a wider audience. It began in Scandinavia, and spread through the rest of Europe and North America (von Post, 1946) and nowadays it is a globally used and independend scientific discipline (Hooghiemstra and Richards, 2022). Since then, palynology has been applied in a wide range of fields, such as: environmental changes (Hao et al., 2021; Krüger et al., 2020), geological (Spina et al., 2020; Vilas-Boas et al., 2022), archaeological (Langgut et al., 2024; Ochando et al., 2022), ecosystem management (Bąk et al., 2024; Słowiński et al., 2019), forensic (Mercuri, 2015; Mildenhall et al., 2006; Walsh and Horrocks, 2008), botanical (Gonçalves-Esteves et al., 2022; Gul et al., 2021), and even medical research (Myszkowska, 2020; Pavón-Romero et al., 2022).

Throughout almost 110 years of its history, palynology as the discipline has been evolving and reaching new fields in environmental sciences (Halbritter et al., 2018; Jiménez-Zamora et al., 2023; Manten, 1966a, 1966b). During this time the use of pollen records in palaeoclimatology has become more quantitative, incorporating more precise and rigorous testing of pollen-climate calibration models against modern climate data (Seppä and Bennett, 2003). Although modern palynology is much more specialized than it was at its beginnings (Rull et al., 2018), even in the 21st century, it still needs to be modified and developed (Edwards et al., 2015; Xu et al., 2024). The necessity of change was also noticed 45 years ago (Frederiksen et al., 1982). Most of the claims raised at that time such as making palynology an interdisciplinary tool or applying computers for statistical analysis of pollen data (Mottl et al., 2021) and drawing charts have already been fulfilled. However, not all goals have been reached – for example, geographic coverage of paleoenvironmental data still requires improvement.

In recent years, bibliometric analysis has become increasingly popular in geosciences (Bezak et al., 2021; Hou et al., 2024; Huang et al., 2023; Zhao et al., 2024). Analysis of database resources containing millions of scientific documents, such as the Web of Science (WoS) or Scopus, allows researchers to capture global trends appearing in particular fields of science, identify emerging topics, uncover collaboration patterns, and research constituents, and also underline the need for enhanced interdisciplinary research in a rapidly advancing fields (Braun and Haluza, 2024; Haunschild et al., 2016; Zhou et al., 2023). So far, the results of bibliometric analyses focussed directly on palynology have not been published. The few previous works on this issue concerned only a narrow scope of palynology, such as forensic and melissopalynology (de Souza et al., 2019; Silveira and de Novais, 2025), or much broader topics, such as research on peatlands, limnology, or climate change, in which pollen analysis is commonly used (Deng et al., 2017; Shi et al., 2024; van Bellen and Larivière, 2020; Yang et al., 2023, 2024). Previous works using different methodologies led to opposite conclusions regarding the state of development of palaeoecological reconstructions based on bioproxies, including palynomorphs (Deng et al., 2017; Yang et al., 2023). This prompted the author to investigate the history and current state of palynology, as well as attempt to determine future trends in palynology as a scientific discipline. The research focussed on a palaeoecological approach to palynology.

Materials and methods

Database

The bibliometric data collection was conducted using the Scopus (Elsevier) database, which is widely regarded as one of the leading global resources for evaluating scientific research. The reason for choosing this database is that, for the period 1950–2023, it contains about 20% more palynological records than WoS. This trend remains almost constant on an annual basis. Moreover, Scopus contains slightly more linguistically diverse documents – 8.4% of articles published in this database were written in a language other than English, while in WoS, this figure is 4.9%. The terms ‘palynology’, ‘pollen analysis’, ‘climate reconstruction’, ‘vegetation history’, ‘palaeobotany’ and ‘palaeoecology’ were searched across article titles, abstracts, authors and index keywords. No filters based on the document type or the language of the original document were applied. The resulting database was then analysed for duplicates. Identified duplicate records were subsequently removed.

The exported Scopus data files were analysed and visualized using the Biblioshiny application, which provides a web interface for the Bibliometrix R statistical package (Aria and Cuccurullo, 2017), as well as Scimago Graphica, a free, no-code tool designed for both visual data communication and exploratory data analysis (Hassan-Montero et al., 2022).

To acquire information about pollen datasets distribution around the world the Neotoma database was used (http://www.neotomadb.org; Grimm and Goring, 2016; Williams et al., 2018).

Citations

To investigate the interest in palynological documents the analysis of their citation has been conducted by calculating two indexes: Mean Total Citation per Year (MeanTCperYear) and Mean Total Citation per Article (MeanTCperArt). The first one provides information about the average number of times each manuscript has been cited yearly. The Mean Total Citation per Article (MeanTCperArt) shows the average total citations per article. The indexes were calculated according to the equations (1) and (2):

M e a n T C p e r Y e a r = \frac{M e a n T C p e r A r t}{C i t a b l e Y e a r s},

(1)

where Citable Years refers to the number of years a document can be cited since its publication.

M e a n T C p e r A r t = \frac{\sum N u m b e r o f c i t a t i o n s}{\sum N u m b e r o f a r t i c l e s},

(2)

Trend analysis

Two terms were used to filter the data from Scopus to analyse trending topics: ‘palynology’ and ‘pollen analysis’. Then, keywords assigned to documents from each group were analysed. The most frequent keywords and the most trending keywords over time were delimited. The minimum number of occurrences per year of each keyword was set to 10. Synonyms, such as for example, ‘palynology’ and ‘palynologie’ or ‘climate change’ and ‘climatic change’ were merged. Also in trending topics analysis the names of the countries were removed.

Results

Overview

According to the Scopus database between 1943 and 2003, 13,451 documents containing the word ‘palynology’ were published in 1632 sources (journals, books, etc.). However, 52 duplicated records were identified so as a result, within the analysed time span, the database contains 1339 unique records. The documents were written by 24,828 authors. Only 1328 documents were singe-authored. 30.61% of documents have international co-authorship, and the average number of coauthors per document is 4.01. The annual document growth rate is 8.11%.

Number of documents

The first document mentioning ‘palynology’ within the title, abstract, or keywords in the Scopus database appeared in 1943. Since then almost every year at least one article on this topic has been indexed in the database. The maximum number of documents – 582 appeared in 2020 (Figure 1). From the mid-1960s till the late 1990s, a moderate increase in a number of documents was observed. After this period up to 2010 dynamic growth appeared and since that year the upward trend has slowed down and a slight downward trend has been observed since 2020.

Figure 1.

The number of articles on palynology published between 1943 and 2023. Rapid growth that began in the 1990s appears to have slowed down in the last two decades.

Spread of palynological research

According to the Scopus database between 1943 and 2023 documents on palynology were written by corresponding authors from 108 countries (Figure 2). The most productive countries are the USA (with 845 corresponding authors), China (830), United Kingdom (761), Germany (620), France (475). Twenty of the most productive countries wrote 54.7% of all documents. When taking into account the affiliations of all co-authors then scientists from 137 countries contributed to palynological studies.

Figure 2.

Most relevant countries conducting palynological research based on corresponding authors from the Scopus database.

The share of multi-country publications within the most productive nations varies between 16.2% (India) to 57.8% (Norway). The group of countries with lower international cooperation include also: Turkey (17%), Poland (19.6%), Argentina (21.9%) and Brazil (23.8%), whereas the most cooperative: Sweden (57.3%), Switzerland (57%), France (55.4%) and the Netherlands (51.8%; Figure 3).

Figure 3.

Share of multi-country publications (MCP) within the 20 most productive countries.

Interest in palynology did not begin simultaneously worldwide. When analysing the number of documents published by five of the most productive nations, it can be observed that the spread of palynological research started in the USA in the 1970s (Figure 4). Around 10 years later a similar trend appeared in the United Kingdom and France, and from the 1990s also in Germany and China. Until 2021, the leader in the number of articles on this topic was the USA, but in 2022 it was overtaken by China. The dynamics of document growth in the analysed countries were similar. The exception is China, which started publishing palynological articles about 30 years after the USA, but from about 2010 the pace of article growth was so high that at the end of 2023, they were the leaders with 5225 documents. The remaining positions are occupied respectively by the USA (4859 documents), UK(4045), France (3626) and Germany (3298).

Figure 4.

Countries’ production over time (cumulative value).

Production over time and most relevant sources

By far the most important source of knowledge is the journal Review of Palaeobotany and Palynology with 1059 palynological articles published between 1967 and 2023. The second place belongs to Palaeogeography, Palaeoclimatology, Palaeoecology with 635 articles, then Quaternary International (597), Quaternary Science Reviews (451), Holocene (446), Palynology (420), Grana (345) and Journal of Quaternary Science (217; Figure 5). In all those journals, apart from Grana, the number of published palynological papers has declined recently. In most of the journals, the shift in the tendency occurred between 2011 and 2016. In Palynology, which is strictly focussed on palynological research, a small decline has been observed since 2021; however, this trend is not significant.

Figure 5.

Eight journals with the biggest number of palynological articles over time. The red line shows the moving average (previous data points −5, next data points −5). In seven out of eight journals, a clear declining tendency has been observed within the last couple of years.

Citation analysis

The five most frequently cited nations conducting research in the palynology field are the USA (30,101 citations), the United Kingdom (27,328), Germany (23,106), China (22,922) and France (17,208). The same countries in slightly different order are the most productive nations in terms of a number of documents. However, within the most citable nations, those with the highest value of average citations index are the Netherlands (49 citations per article), Switzerland (48.4), Germany (37.3), France (37.3) and the United Kingdom and Sweden (both 35.9; Figure 6).

Figure 6.

The most cited countries (total citations) and the average article citation index.

From the 1950s till 1997 gradual growth of Mean Total Citation per Year (MeanTCperYear) is observed (Figure 7). Between 1997 and 2010 a significant increase is observed and at the end of this period, the index reaches its maximal value of 2.54 citations. After this phase, the average citation per year stabilizes at around 2.25 until 2020 and then begins to decline. The picks in MeanTCperYear that appear during this period are also clearly visible in Mean Total Citation per Article (MeanTCperArt). This index reached the highest values in 1976 – 58.44 citations per article. However, that year only 18 articles were published, and the high value is affected by four articles that were cited more than 100 times.

Figure 7.

Mean Total Citation per Year (MeanTCperYear); Mean Total Citation per Article (MeanTCperArt). Significant decline in citations in last years.

Discussion

Evolution of Quaternary palynology

The oldest document occurring in the Scopus database when searching the term ‘palynology’ is an article by Sayles and Knox (1943), however, the term appears only within the index keywords assigned later by Scopus professional indexers. According to Edwards and Pardoe (2018) the term ‘palynology’ was proposed in 1944 by Hyde and Williams (1944) and quite soon after the publication it was accepted and recognized by the international scientific society. When analysing bibliometric trends based on the term ‘pollen analysis’ instead of ‘palynology’, the query yields more records from the early stages of the discipline. The oldest result come from 1932 and it is an anonymous review note published in Nature (Anonymous, 1932). However, when looking at the list of references cited in the documents from this period (e.g. Bertsch, 1942), it becomes apparent how incomplete the database is and that many important works from the first half of the 20th century, which were crucial to the development of the discipline (e.g. Barkley, 1934; Erdtman, 1931; Lewis and Cocke, 1929). Another issue is that not all palynological reports, particularly those related to oil exploration, were permitted to be published in international journals and thus remained confidential (Hooghiemstra and Richards, 2022).

Birks and Berglund (2018) divide the history of Quaternary pollen analysis into three phases: the pioneer phase – 1916–1950, the building phase – 1951–1973, and the mature phase – from 1974 till today. The division was proposed based on milestone publications as well as on technological and methodological advances in pollen analysis and palaeoecology; nevertheless, it corresponds quite well with the changes in the number of palynological documents in the Scopus database. The first period started with von Post’s lecture at the 16th Scandinavian Meeting of Natural Scientists in Kristiania (now Oslo) and lasted till 1950 when Fægri and Iversen published their Text-book of Modern Pollen Analysis (Faegri and Iversen, 1950). From this phase only five documents were indexed in the Scopus database, however, it has to be remembered that at that time scientific publishing differed a lot from modern standards, for example, there were much less scientific journals, and scientists published much more often in their national languages, using keywords was not a common standard. The building phase ended with the publication of the symposium volume Quaternary Plant Ecology (Birks and West, 1973). From this period 175 documents are indexed in Scopus. The annual growth rate of documents in this period was 9.91%, around half of the documents were single-authored, and only 2.3% of all documents had international co-authorship. During the mature phase (1974–2023) 13,271 documents were indexed in Scopus, the annual growth rate dropped slightly to 7.9%, but the number of single-authored articles decreased to 9.5%, and the international co-authorship index increased to 31%. However, if the upper bound on the mature phase is set in 2016 (100 years after von Post’s presentation, also a year that may have marked the ca. 2500th birthday of palaeoecology (de Klerk, 2017)), and if a new – ‘modern phase’ starting from that date is distinguished then a clearly different trend may be observed (Figure 10). The modern phase (2017–2023) according to bibliometric analysis is characterized by a negative value of the annual growth rate reaching −0.58%. Parallelly the co-authors per document index grows to 5.3 and the percentage of international documents rises to 38.12.

Figure 10.

Changes in Annual Growth Rate, International co-authorship, and Co-authors per Document indexes during four phases of Quaternary palynology development.

The increasing number of palynological documents has already been noticed by Manten (1968a, 1968b, 1970) and Edwards et al. (2015). Although the increase in the number of documents and authors as well as a high percentage of multiple authorship indicates the development and specialization of the discipline (Manten, 1968a), already in 1983 Edwards (1983) noticed the problem of overproduction of case studies and the need to develop syntheses based on existing palynological data. In 2015 Edwards et al. (2015) also suggested that published research may have a replicative or incremental character. Moreover, they also highlighted that modern palynologists increasingly must either be adept at or able to join forces with statisticians and modellers to move the discipline forward.

Is there still a terra incognita for palynologists?

Despite more than a 100 years of history of using the pollen analysis method in Earth sciences, most of the researches were conducted within the two hot spots: Europe and North America (Figure 11). The figure shows the distribution of pollen datasets uploaded to a Neotoma database (http://www.neotomadb.org; Grimm and Goring, 2016; Williams et al., 2018). On 13th December 2024, there were 6614 pollen datasets uploaded to the database. Only 18.7% of all pollen data do not come from the two hotspots. When only the data used for pollen-based climate reconstructions are extracted from the Neotoma database the contrast between the Northern Hemisphere and the rest of the world is even more visible (Chevalier et al., 2020).

Figure 11.

Geographical distribution of pollen datasets from Neotomadatabase (Williams et al., 2018), including its regional constituent databases: the European Pollen Database (EPD) and Alpine Pollen Database (ALPADABA; Fyfe et al., 2009), the African Pollen Database (Lézine et al., 2021), the Indo-Pacific Pollen Database (IPPD; Herbert et al., 2024), the North American Pollen Database (NAPD; https://www.ncei.noaa.gov/products/palaeoclimatology), and the Latin American Pollen Database (LAPD; Flantua et al., 2015).

Analysis of dataset distribution along the elevation gradient shows that 48.7% of the sediment cores were collected from sites located between 0 and 250 m a.s.l. and below 1000 m a.s.l. – 77.7% (Figure 12). Neotoma database must be supplied with data by data stewards, so it is not complete and it does not show the current state of worldwide palynology. Nevertheless, it can be assumed that it reflects global trends, as well as points out the blank spots on the map of palynological research. The overrepresentation of temperate regions in the Northern Hemisphere was already noticed and discussed during the Twelfth Annual Meeting of the American Association of Stratigraphic Palynologists in 1979 (Frederiksen et al., 1982).

Figure 12.

The distribution of pollen datasets along the elevation gradient from the Neotoma database shows that most of the data were collected from easily accessible locations.

The most commonly used natural sedimentary archives for palynological research are lakes, wetlands, or marine sediments. However, pollen deposited in glacier ice can provide as well useful information on climate and vegetation variations (Brugger et al., 2019; Cui et al., 2022; Festi et al., 2023), and also pollen concentration peaks may be used in distinguishing and dating annual layers in ice cores (Middeldorp, 1982; Takeuchi et al., 2019). Nevertheless, due to the relatively high costs of drilling and demanding technical, storing and logistic issues, ice cores are relatively rare objects of palynological research. In addition to obtaining data from new drilling, there is still untapped potential in deep-sea and ice cores that have already been collected and could be used in the palaeo-reconstructions.

The glacial depositional environment seems to be not the only one that is insufficiently used in palynological research. Other potential archives of palynomorph data are caves. Cave deposits are a valuable source of paleoenvironmental data, especially in arid areas where conventional depositional environments such as lakes and wetlands do not exist or are limited (Carrión et al., 1999; Davis, 1990). These environments are challenging in terms of sampling, laboratory treatment, and interpretation of the results (Carrión et al., 1999, 2022; Coles et al., 1989; Hunt and Fiacconi, 2018), however they may bring reliable information on the external environment (Burney and Burney, 1993; Hunt and Fiacconi, 2018). Not only cave deposits may be a source of modern and fossil pollen but also fossil and modern bat guano (Basumatary and Tripathi, 2021; Marais et al., 2015; Navarro Camacho et al., 2000), spider’s webs (Navarro Camacho et al., 2000), moss pollsters (Burney and Burney, 1993; Navarro Camacho et al., 2000), spelaeothems (Dickson et al., 2023; Festi et al., 2016; Luetscher et al., 2021; McGarry and Caseldine, 2004) or cave ice (Feurdean et al., 2011; Leunda et al., 2019).

Palaeoecological databases like Neotoma, PANGAEA or the European Pollen Database are growing both in terms of the volume of data collected and their thematic scope. This growth is opening up new opportunities for paleoenvironmental research (Flantua et al., 2023). Additionally, the development of information technologies, including artificial intelligence, makes data mining based on already acquired drilling data from around the world easier. This facilitates the creation of scientific syntheses that may reveal spatio-temporal trends in climate change (Routson et al., 2022; Shuman et al., 2023), past ecosystem evolution and its dynamics (Bhatta et al., 2023; Mottl et al., 2021) or improve ecological forecasting (Allen et al., 2019; Nogués-Bravo et al., 2016). Data mining of those resources allows to study continental- to global-scale changes over geologic to human time scales (Blois et al., 2013; Dawson et al., 2016). Such analyses would be impossible or difficult to conduct using data from only one or a few sites.

What can the bibliometry say about the state of palynology?

The origin of the corresponding authors shows that during the past 80 years, palynology became a globally renown and applied discipline. The comparison of nations with a high share of multi-countries publications and average article citations shows that international cooperation increases the chances for citations. This suits the observation by Olechnicka et al. (2019).

The small number of documents written by one author (just 9.98% of documents are single-authored), and the average number of co-authors per document – 4.01 show that palynology nowadays is rather used as a piece of the puzzle in palaeoecological reconstructions. This fits in with the trend of growing interest in multi-proxy research in palaeosciences (Lotter, 2003). The essential aspect of a multi-proxy study is that several proxies are used simultaneously to investigate a particular problem, event, process, etc. (Birks and Birks, 2006) which is why it is better to support for example, pollen-based environmental reconstruction with other proxies like plant macrofossils, geochemistry, testate amoebae, grain-size analysis, charcoal analysis etc., to achieve a wider and more complete overview of past environmental conditions. From the author’s perspective, multi-proxy, and as a result, multi-authored publications may be of higher value than single-authored works, because they not only increase the average number of citations (Abt, 1984; Sanfilippo et al., 2018) but also increase the probability of acceptance of the manuscript (Smart and Bayer, 1986).

The declining number of articles in the last couple of years containing strongly related to palynology keywords, such as ‘palaeoecology’, ‘climate reconstruction’, ‘vegetation history’ or ‘palaeobotany’ may reflect a wider trend in palaeostudies (Figure 13). However, the decrease in the frequency of some keywords does not necessarily reflect a negative situation. For example, ‘vegetation history’ may be compensated by the increase in others like ‘climate reconstruction’.

Figure 13.

Annual scientific production of documents containing the following keywords: ‘palaeoecology’, ‘pollen analysis’, ‘climate reconstruction’, ‘vegetation history’ and ‘palaeobotany’. Only ‘climate reconstruction’ shows an upward trend, while the other keywords have either stabilized or show a downward trend.

Deng et al. (2017) analysing the 50 most frequently used keywords in climate change and lake research between 1991 and 2015 revealed that keyword trends related to ‘paleo-’ decreased the most significantly, and keywords ‘palaeoecology’, ‘palynology’ and ‘pollen analysis’ were among the five results with the biggest drops. A similar trend was observed in the bibliometric analysis of works focussed on peatland research (van Bellen and Larivière, 2020). Nevertheless, in terms of the number of publications and not the growth dynamics, paleoresearch on peatlands still ranks second after research on carbon dynamics (Yang et al., 2024).

Bibliometric analysis of the most frequent words used in author keywords reveals that however palynology has a wider mining than pollen analysis, it occurs that the term palynology is usually used in palaeoecological context whereas pollen analysis occurs much more often in other fields such as melissopalynology, archaeology, and aerobiology. The trending topics analysis also reveals the technical revolution (evidenced by topics such as ‘deep learning’, ‘SEM’ and ‘exine ornamentation’) that has been happening in palynology over the last two decades. Trend analysis reveals that the discipline is evolving, reaching new fields, and becoming more automated and quantitative (Gimenez et al., 2024; Punyasena et al., 2022; Seppä and Bennett, 2003; Xu et al., 2024). However, optically automated pollen counting has not reached broad-scale application so far (Edwards et al., 2017) which is why Quaternary pollen still has room for improvement.

The declining trend in palynological research may also be related to the demanding nature of pollen analysis (time-consuming, expensive, requiring qualified staff, etc.), which could lead to a general decrease in the number of palynologists.

The growing interest in new geographical study sites such as the tropics, the Chinese mainland, glaciers, or caves may suggest that the gap in palaeoecological research between the temperate zone of the northern hemisphere and the rest of the world will be shrinking.

Limitations

Bibliometric studies have many advantages, and the fact that they show the trends and directions in which individual research areas are heading is undoubtedly the greatest of them. However, every bibliometric research requires databases (e.g. Scopus, Web of Science, Dimensions, etc.), which have limitations. First of all, any database does not contain all published documents from particular topics but is restricted to those from the journals, books, proceedings, etc. that are indexed in it (Passas, 2024). In the context of palynological research, evidence of the incompleteness of contemporary databases, especially in the early stages of the discipline’s development, can be found in the bibliography of contemporary documents (e.g. Bertsch, 1942; Faegri and Iversen, 1950). Additionally, an excellent source of information on the development of palynological analysis is a series of articles by Gunnar Erdtman titled Literature on Palynology, which constitutes a very rich bibliographic database divided by subdisciplines, sediment age, and country (e.g. Erdtman, 1947, 1949, 1954) or a series of 18 issues entitled Pollen Analysis Circular and Pollen and Spore Circular published between 1942 and 1954. Another issue is the overrepresentation of English language journals and, as a result, the overrepresentation of documents from English-speaking countries (Vera-Baceta et al., 2019). In consequence, documents written in a language other than English and published in a non-indexed journal may not be so easily recognized worldwide and not contribute to a global state of knowledge.

Another limitation is the differences in Authors and Index Keywords. The number of Authors Keywords differs within particular journals, what is more, they do not always well describe the content of the document. Also, not all publications contain them. That is the reason why databases use also Index Keywords to enrich the publication with metadata which may help in better positioning and recognition of publications. Usually, the article indexed in Scopus or w WoS has more Index Keywords assigned than Author’s Keywords. Another limitation is that the bibliometric analysis is based on particular words that have to appear within the title, abstract, or keywords; otherwise, the article will not be included in the analysis.

Conclusions

Bibliometric analysis of palynological documents shows the variability of the dynamics of interest in the subject. Throughout almost 110 years of its history, palynology has became a globally renown and applied dyscipline. The dynamic of its evolution has changed through time. For years, scientists have been trying to expand the use of pollen analysis beyond palaeoecology, aiming to establish it as an interdisciplinary science with applications in various fields. Nowadays, multi-proxy and transdisciplinary studies became a common attempt. However, the trends observed in recent years – declining annual growth rate of palynological papers, raise the question of whether the mature phase described by Birks and Berglund (2018) is still ongoing, or perhaps we are witnessing the beginning of a new – modern phase. Another issue is whether this phenomenon is unique to Quaternary palynology or if it is part of a broader challenge in palaeoecological studies. Obtained results suggest that palynological research has either reached a state of stability – a climax, or has reached its limits regarding scientific productivity. However, the discipline is evolving and is being applied in new fields so the trend may change in the future, unless palynologists remain nimble, creative, and collaborative (Edwards et al., 2017). For example, the development of information technologies and global databases, such as Neotoma, enables data mining in palynological research. This allows researchers to identify spatio-temporal patterns and create syntheses that would be impossible with the analysis of just a single site or only a few. That could be a milestone in future palynological studies. Another approach to advancing the discipline could be to go beyond the beaten path and conduct research, looking for still not well-explored depositional basins such as glaciers, cave silts, speleotherms, or cave ice, sites located in hard-to-reach places, such as mountains, or in parts of the world that have not yet been sufficiently explored.

Footnotes

Acknowledgements

Data showing the distribution of pollen datasets were obtained from the Neotoma Palaeoecology Database (). The work of data contributors, data stewards, and the Neotoma community is gratefully acknowledged. The author sincerely thanks the reviewers for their constructive comments and valuable suggestions, which helped improve the quality of this manuscript.

Author contribution(s)

Jan Barabach: Conceptualization; Data curation; Formal analysis; Investigation; Methodology; Project administration; Validation; Visualization; Writing – original draft; Writing – review & editing.

Funding

The author(s) disclosed receipt of the following financial support for the research, authorship and/or publication of this article: The publication was financed by the Polish Minister of Science and Higher Education as part of the Strategy of the Poznan University of Life Sciences for 2024-2026 in the field of improving scientific research and development work in priority research areas.

Ethical approval and informed consent statements

This article does not contain any studies with human or animal participants.

ORCID iD

Jan Barabach

Data availability statement

Data used for this work were exported from the Scopus database. They can also be requested by contacting the corresponding author.

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Has Quaternary palynology reached its climax?

Abstract

Keywords

Introduction

Materials and methods

Database

Citations

Trend analysis

Results

Overview

Number of documents

Spread of palynological research

Production over time and most relevant sources

Citation analysis

Trending topics

Discussion

Evolution of Quaternary palynology

Is there still a terra incognita for palynologists?

What can the bibliometry say about the state of palynology?

Limitations

Conclusions

Footnotes

Acknowledgements

Author contribution(s)

Funding

Ethical approval and informed consent statements

ORCID iD

Data availability statement

References