Human impact on Central European forests dates back thousands of years. In this study we reanalyzed 36 published pollen data sets with robust chronologies from Polish Lowlands to determine the ...patterns of large-scale forest decline after the Migration Period (fourth to sixth century CE). The study revealed substantial heterogeneity in the old-growth forest decline patterns. Using new high-resolution studies, we could better understand the timing of this transition related to increasing economic development. After the Migration Period, forest expansion continued until the seventh to ninth centuries cal. CE, when the dawn of Slavic culture resulted in large-scale forest decline, especially in north-western and north-central Poland. Later, forest decline was recorded mainly in north-eastern Poland and was related to Prussian settlements, including activities associated with the Teutonic Order, as well as with new settlements from the fourteenth century. The composite picture shows a varied spatio-temporal forest loss and transition towards the present-day, human activity dominated landscapes. However, some sites, such as in north-eastern Poland, are characterized by a less abrupt critical transition. The pristine nature of the oak-hornbeam forest had already been destroyed in Early Medieval times (eighth to ninth centuries cal. CE) and the potential for recovery was largely lost. Our study has confirmed previous assumptions that the decline of hornbeam across the Polish Lowlands may be an early indicator of local settlement processes, preceding severe forest loss, and establishment of permanent agriculture.
Peatlands perform many important ecosystem functions at both the local and global scale, including hydrologic and climatic regulation. Although peatlands often act as climatic microrefugia, they have ...rarely been the subject of long-term microclimatic studies. In this study, we aimed to compare the local climatic conditions of a mid-forest mire to that of an open area and examine the differences in microclimates within the mire based on plant community diversity, shading, and water table depths. The peatland studied in this work was significantly cooler than the reference site, mainly due to a higher decline in nighttime air temperatures. However, the daily maximum air temperature near the ground was often higher. We also noticed that microclimates significantly differed within the studied peatland. Wet and shaded microsites were cooler than the sites having a lower water level and receiving higher amounts of solar radiation. The results of the study suggest that peatlands have locally cooler climates, and thus can serve as climate change refugia. These findings can help us interpret reconstructed data from the peat archive, and, when combined with experiments, identify tipping points for peatland ecosystems.
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•Multi-proxy palaeoecological studies in the Białowieża Primary Forest.•Palaeoecological analysis as a reliable tool to determinate state of the peatland and forest ecosystems ...conditions.•Peatland ecosystems in the Białowieża Forest may no longer be in a pristine state.•Permanent high fire activity between ca. 1650 and 1920 in the Białowieża Forest.
The Białowieża Primeval Forest is one of the most pristine forested and peatland areas in Europe, as recognized by its status as the World Biosphere Reserve. Palaeoecological analyzes offer the possibility of establishing a record of ecosystem change over time, and therefore setting reference conditions for their assessment, protection and restoration. To assess the impact of hydrological changes, fire and pollution (dust, metals from smelting) on peatland and forest ecosystems, we carried out high-resolution, multi-proxy palaeoecological investigations of two peat cores (50 cm long) from nearby locations at a peatland located in the protected area (nature reserve) of the Białowieża Forest (CE Poland). Our study revealed that: i) between about 1780 and 1920 CE high fire activity likely caused by humans led to a partly decline in dwarf shrubs at the sampling sites; ii) between about 1910 and 1930 CE distinctive changes in local and regional plant succession took place that can be considered as a sign of disturbance in the peatland ecosystems; iii) during the last three decades we recorded a recent decrease of trace metals and pollen indicating a decrease in human activity. These changes are synchronous with a decrease of industrial activity and curbing of emission through legislation as well as the ongoing depopulation of villages in E Poland that started in 1990.
Our data suggest that even well-preserved peatlands, located in protected areas might be far from their pristine state, predominantly due to disturbance effects from the past still lingering on. Nevertheless, the studied area remains one of the best-preserved forest ecosystems in Europe, despite the negative impact of human activity (deforestation, fires, hunting) over the past few centuries.
Landslide mountain fens formed in landslide depressions are dynamic environments as their development is disturbed by a number of factors, for example, landslides, slopewash, and surface run-off. ...These processes lead to the accumulation of mineral material and wood in peat. Disturbed peatlands are interesting archives of past environmental changes, but they may be challenging for providing biotic proxy-based quantitative reconstructions. Here we investigate long-term changes in testate amoeba communities from two landslide mountain fens – so far an overlooked habitat for testate amoeba investigations. Our results show that abundances of testate amoebae are extremely low in this type of peatlands, therefore not suitable for providing quantitative depth-to-water table reconstructions. However, frequent shifts of dominant testate amoeba species reflect dynamic lithological situation of the studied fens. We observed that high and stable mineral matter input into the peatlands was associated with high abundances of species producing agglutinated (xenosomic) as well as idiosomic shells which prevailed in the testate amoeba communities in both analyzed profiles. This is the first study that explores testate amoebae of landslide mountain fens in such detail, providing novel information about microbial communities of these ecosystems.
The Central European area has been extensively studied using qualitative reconstruction techniques focusing on the development of peatlands in the past; however, research based on quantitative ...techniques is still lacking, especially in relation to highlands and mountainous areas. In this study, we focused on the hydrological changes and human-induced disturbances that affected two raised bogs from the Orawa-Nowy Targ Basin (Carpathian region): Puścizna Krauszowska and Puścizna Mała. We aimed to reconstruct the development of peatlands and changes in water table under different intensities of human activities. Two peat sequences from two different bogs, both possessing absolute chronologies based on high-resolution 14C dating, were examined in terms of pollen, non-pollen palynomorphs, plant macrofossils and testate amoeba records. We detected an asynchronous decrease in the water table level on the bogs that took place between the 4th and the 7th century ad, which occurred simultaneously with a global cold period ad 300–600 (Migration Period) in case of the Puścizna Mała bog. A concurrent but insignificant human impact on bogs was recorded. A distinct wet shift corresponding to the Wolf solar minimum (ca. ad 1280–1340) in Puścizna Mała was detected during ca. ad 1300–1350. The effect of this climatic event on bog hydrology is difficult to estimate because of the simultaneous human-induced deforestation. Drainage and substantial acceleration of peat extraction in the 19th and the 20th century ad led to the significant disturbances in peatland; however, these bogs were still susceptible to dry climatic events.
Mountain regions harbour high biodiversity; however, in numerous areas, they are strongly degraded by human activity. Our study reconstructs the development of the submontane forest belt (400 and 650 ...m a.s.l.) in the Beskid Wyspowy Mountains (Western Carpathians, Central Europe) affected by climate, humans, fire, and parasitic fungi during the Holocene. This forest belt is considered the most transformed by the human in the Carpathian region. Our multi-proxy study included analyses of pollen, non-pollen palynomorphs (NPPs), plant macrofossils, micro- and macrocharcoal (size fraction >100 µm, analysed in contiguous sampling), geochemical, and sedimentological markers. The results revealed that Picea abies dominated on the fen subjected to study at ca. 8510–5010 cal. BP. Tilia cordata was a substantial component of the submontane forest between ca. 8510 and 2970 cal. BP and it survived a probable Kretzschmaria deusta outbreak, as well as a period of increased fire activity (ca. 6000 cal. BP). The final retreat of forests with a substantial contribution of Tilia was induced by the expansion of Abies alba, Fagus sylvatica, and partly Carpinus betulus and was preceded by the period of increased fire activity and erosion. From ca. 900 cal. BP human-induced deforestations and agricultural and pastoral activity increased. The modern presence of woodlands with Pinus sylvestris and Larix decidua, in the submontane zone in the Beskid Wyspowy Mountains, is a result of sub-recent anthropogenic afforestation on overgrazed areas. The example of the Zbludza site reveals that changes related to fire and pathogen infections, if they have low magnitudes and new competitive taxa are absent, may be reversible in a forest composed of fire-intolerant tree taxa as Tilia. Nonetheless, the widespread submontane ecosystem degradation and the introduction of alien species hamper the regeneration of forest vegetation typical of the submontane zone.
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•All proxies showed a shift towards drier environmental conditions starting from 920 cal. CE.•Human activities and climate change left clear signatures in the Wölflmoor peat bog.•eDNA ...metabarcoding gave results with similar trends as the other proxies but highlighting some methodological limitations.
In the last decades, climate and human activities significantly affected ecosystems, particularly in mountain areas. Whereas the Alps have been extensively studied for palaeoclimatic reconstructions, little information is available about ecological changes, especially in the Southeastern Alps. This study presents a palaeoclimatic and palaeoecological reconstruction from a 1500-years-old mountain peatland record: Wölflmoor, Bozen (Italy).
Through Physico-chemical proxies, testate amoeba, pollen, plant macro-fossils, and environmental DNA (eDNA) analyses, we pursued a twofold objective: 1) reconstructing the palaeoenvironmental variations of the peatland and the surrounding environment to identify the main dry/wet periods, and their correlations with climate and human activities; 2) testing the use of eDNA from a peatland in palaeoecological reconstructions. The dating highlighted a distinct change of age at a depth of 55.5–50.5 cm (ca. 800–930 calibrated years), which suggests a depositional gap (hiatus), at least in this section, occurred during the Medieval Warm Period, due to the increase in air temperature. However, the possible exploitation of the peatland by humans cannot be excluded. Indeed, the increase of Poaceae, Cerealia type, and Secale cereale, and the reduction of Fagus sylvatica and Quercus presented a high human pressure starting around 720 cal. CE. Environmental DNA metabarcoding results showed similar trends. However, it gave limitations such as the preferential amplification of the most abundant species, leading to a relatively small number of detected taxa. This is one of the first studies of eDNA metabarcoding from peatland; thus, we argue that ample room for improvement is expected in a short time, making eDNA metabarcoding a valuable complementary approach, primarily when both flora and fauna taxa are targeted.
Peatlands are important records of past environmental changes. Based on a multiproxy analysis, the main factors influencing the evolution of a peatland can be divided into autogenic and allogenic. ...Among the important allogenic factors, apart from climate change, are deforestation and drainage, which are directly associated with human impact. Numerous consequences arise from these processes, the most important of which are physical and chemical denudation in the catchment and the related hydrological disturbances in the catchment and peatland. The present study determined how human activities and the past climatic variability mutually influenced the development of a small peatland ecosystem. The main goals of the study were: (1) to trace the local changes of the peatland history over the past 600 years, (2) to investigate their relationship with changes in regional hydroclimate patterns, and (3) to estimate the sensitivity of a small peatland to natural and human impact. Our reconstructions were based on a multiproxy analysis, including the analysis of pollen, macrofossils, Chironomidae, Cladocera, and testate amoebae. Our results showed that, depending on the changes in water level, the history of peatland can be divided into three phases as follows: 1/the phase of stable natural conditions, 2/phase of weak changes, and 3/phase of significant changes in the catchment. Additionally, to better understand the importance of the size of catchment and the size of the depositional basin in the evolution of the studied peatland ecosystem, we compared data from two peatlands – large and small – located close to each other. The results of our study indicated that “size matters,” and that larger peatlands are much more resilient and resistant to rapid changes occurring in the direct catchment due to human activities, whereas small peatlands are more sensitive and perfect as archives of environmental changes.
This review provides a synthesis of current knowledge on the morphological and functional traits of testate amoebae, a polyphyletic group of protists commonly used as proxies of past hydrological ...changes in paleoecological investigations from peatland, lake sediment and soil archives. A trait-based approach to understanding testate amoebae ecology and paleoecology has gained in popularity in recent years, with research showing that morphological characteristics provide complementary information to the commonly used environmental inferences based on testate amoeba (morpho-)species data. We provide a broad overview of testate amoeba morphological and functional traits and trait-environment relationships in the context of ecology, evolution, genetics, biogeography, and paleoecology. As examples we report upon previous ecological and paleoecological studies that used trait-based approaches, and describe key testate amoebae traits that can be used to improve the interpretation of environmental studies. We also highlight knowledge gaps and speculate on potential future directions for the application of trait-based approaches in testate amoeba research.
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