Since 1993 you have been heading the Laboratory of Paleoecology and Archaeobotany, which you yourself organised. Is a paleoecologist more of a biologist or an archaeologist?

Certainly first of all a biologist, and maybe not necessarily an archaeologist but more of a geologist. This is a typically interdisciplinary branch which calls for a basic, and at times even beyond a basic, knowledge of biology, archaeology and geology. This is why paleoecologists are educated in quite different ways, with an archaeologist sometimes learning biology and ecology to be able to occupy with paleoecology. The same goes for geologists who very often educate themselves in certain branches of biology to be able to work in this speciality. Paleoecology is nothing more than looking into the past of the natural environment. Every single year in the life of planet Earth has left behind different kinds of traces which accumulate in the form of fossil material. The role of a paleoecologist is to find these traces and identify and interpret them in order to reconstruct the history of the environment  –  the history of particular ecosystems, climatic changes and various natural ‘events’ which took place in the past.

And the anthropogenic influences as well?

Of course, the anthropogenic influence as well because man gradually altered nature as he stepped into it. Under man’s influence new forms of plant communities developed. The particularly important changes appeared with the development of agriculture, when forests were not only gradually replaced by fields, meadows and pastures but there was also a change in the geographical range of many species. These processes are connected not only with our most recent history but have been going on for many thousands of years. Through paleoecological research, with palynology being of prime importance, we can reconstruct the way in which plant communities evolved and how the Earth’s environment changed as a result of demographic shift and the development of settlements and economy. 

You have devoted many years of archaeobotanical research into Gdańsk’s natural past.

It is research which I initiated but which is the work of my team, my colleagues and also our students because many MA diplomas have been written on the basis of the archaeobotanical material from Gdańsk.  Since 1998 we have assembled material from about 30 archaeological sites in the Gdańsk area. We have accompanied archaeologists and collected samples from layers which formed prior to the settlement has been established and those formed during the city’s development. Such samples are used to obtain plant material. In the case of our research, the results of the analyses were examined from two different perspectives. First, in terms of the history of the plants used by the residents of the city from the early Middle Ages to modern times. In this field a book by Dr hab. Monika Badura, accepted as her habilitation dissertation, seems to be a particular achievement. The second aspect of the research covers the reconstruction of changes in the natural environment in the Gdańsk area; this topic is currently being tackled mainly by Dr Joanna Święta-Musznicka. Archaeobotanical research of cities such as Gdańsk requires cooperation not only with archaeologists but also with historians. This interdisciplinary cooperation is one of the most interesting aspects of our work.

The large project “Migration Period between the Oder and the Vistula” must have also involved a similar scope of research.

This is a project by archaeologists from the University of Warsaw, in particular Professor  Aleksander Bursche, a MAESTRO project by the National Science Centre in which I am responsible for the palaeoecological part. Our task involves the collection of data which would allow for the assessment of regional differentiation in the scale of the changes in forest cover and the traces of human activity between the end of the Roman Period and the early Middle Ages, mainly in Northern Poland. To put it more succinctly, by relying on a certain category of natural sources (palynology) we try to answer the question if everyone in certain regions just ‘upped’ and left during the so-called Migration Period or if certain settlement enclaves remained.

I have been greatly impressed by the techniques used by an archaeobotanist. In five samples, 1.5 litres in total, I am speaking of the research in the Royal Castle in Warsaw, 8,280 macro-remains were identified under the microscope, often less than 1 mm in size.  It is truly laborious work!

Yes, indeed, both archaeobotany and paleoecology demand extremely time-consuming work and great professionalism when it comes to classifying fossil material. The more than 8,000 remains you’re talking about is not such a staggering number compared to what we normally deal with, with isolating them being a simple technical task resembling the task of Cinderella from the fairy tale.  It is the classification of such material which calls for professionalism and allows a data base to be established, which in turn provides a starting point for the reconstruction of changes to the environment or allows us to examine the question of plant use. These types of remains, although bearing the name ‘macro’, are of course small, but grains of pollen, our main research material, are even smaller. They are tens of micrometres in size, and in just one sample we classify and count around 1,000 grains of pollen and other ‘particles’ which have remained in their fossil state. One sample often contains dozens of taxons, and we’re generally dealing with hundreds of potential classification possibilities. Yes, it is massive work which requires long training and I must say that my team has attained this excellent level of professionalism. As a result, we can boast both interesting results and interesting colaboration on the international level as well. However, all this time-consuming laboratory and microscope work is just a stage which provides data for solving specific research problems. And this is where the most interesting stage of our work begins.

This must be a masterwork already. What are you currently working on, Professor?

Together with my team I am currently working on several projects. Paleoecology is fascinating because, amongst other things, we have the tools and methods to help us solve a great deal issues of various kinds. I can mention two interesting topics which I have recently been particularly involved in. One of our current fascinations is the history of Białowieża Forest. It is our own interdisciplinary project to which we have also invited other specialists. Given the ideas currently being forced by the state foresters concerning the ‘healing’ of the Białowieża Forest, the results of our research are particularly topical and it would be good if the resulting conclusions reached practitioners. The history of forests, just like the history of other elements of the natural environment must be looked at from a long-time perspective, relative to their longevity and the pace of on-going change. Consequently, we cannot assess the currently observed processes from the perspective of our own life, or the observations lasting dozens of years only. Forest ecosystems are subject to constant change, the exchange of dominant species is a natural process, while insect outbreaks or parasitic diseases appear from time to time, only to disappear again. These are processes which take place over the scale of hundreds or thousands of years. This is how we also have to look at the current outbreak bark beetles killing spruce trees in Białowieża Forest. Spruce have been present in the area for several thousand years but a main expansion took place around one thousand years ago. Since that time, the spruce population has undergone numerous significant fluctuations and its present situation is nothing out of ordinary. In turn, a completely different way of making use of palynological data forms the basis for the international project LANDCLIM (LAND cover – CLIMate interactions in NW Europe during the Holocene) in which I am participating. The project is headed by Professor Marie-José Gaillard from Sweden and the aim is to reconstruct the landscape of Europe in different periods, going back to the early Holocene – the share of forest cover, the proportion of deciduous trees and evergreens, or the proportion of farmland area. The data is later used as an element in climate change modelling. It is based on the assumption that the type of plant cover has a significant influence both on the Earth’s albedo as well as on gas exchange, including the level of so-called ‘greenhouse gases’ in the atmosphere. 

And finally, Professor, what does a paleoecologist do in her free time?

I must say that I am a person who suffers from a lack of free time. I have a family of four generations so I have plenty to do outside work. I have more dreams about how I would like to spend my free time than the options to fulfil them. If I do happen to find a moment, then I reach for a stack of books which I have gathered and pull out a book suited for my present frame of mind. I like reading a good article and often reach for professional literature outside my own field, mainly concerned with the evolution of man or the history of the development of societies in remote, exotic areas. There are many things I am interested in and which I wish I had more time to explore.

Thank you for the interview, Profesor.

Gdańsk, 18 February 2016

Interview: Dr Tadeusz Zaleski
Photography: Piotr Pędziszewski