ID29: Historical ecology of alpine environments

Abstract ID 396 | Date: 2022-09-14 10:11 – 10:22 | Type: Oral Presentation | Place: SOWI – Lecture hall HS2 |

Gamba, Emma (1); Isoardi, Delphine (2); Talon, Brigitte (1)

Today more than ever, we need to learn from the past to anticipate the future. Here we propose an historical ecology focus on the Faillefeu forest, which is a typical example of what we could call an “old growth forest”. Since at least the Middle Ages, it has been exploited by humans for various uses (sylvo-pastoralism, firewood, export for shipyards) and it is today left to evolve freely without any particular management. We aim to reconstruct the role of human activities in the establishment of the structure and biodiversity of the Faillefeu forest over the long term (from prehistory to modern times) by an interdisciplinary approach between paleo-environmental (pedoanthracology) and historical data. Thanks to a large corpus of historical data (ONF archives, RTM, maps, and archaeological surveys), the human presence is well known in this forest since at least the 10th century. However, the impact of these activities on forest trajectories remains unknown. Moreover, the archives mention the presence of beech and fir trees, the current forest of Faillefeu is composed of fir and spruce in its lower part and of larch and Scots pine in its upper part, some of which are several hundred years old. But the beech is absent today. In order to compensate the lack of paleoenvironmental data and to try to provide some answers about the forest dynamics of the forest, two transects of pedoanthracological pits were made along an altitudinal gradient and arranged in opposition to the slope. The soil-anthracological analyses are currently being processed and will determine if the past forest composition is the same as today. The objective is to assess the resilience of this forest faced with multi-century exploitation. Finally, the presence of beech is also sought to be demonstrated.

Abstract ID 437 | Date: 2022-09-14 10:22 – 10:33 | Type: Oral Presentation | Place: SOWI – Lecture hall HS2 |

Meyer, Michael (1); Gliganic, Luke (2); May, Jan-Hendrik (3); Aldenderfer, Mark (4)

The Tibetan plateau is one of the highest contiguous high-elevation terrains on earth and has a long history of human exploration and occupation, extending at least into the Late Pleistocene. Here we present an integrated earth surface process and paleoenvironmental study from the Tingri graben and the archaeological site of Su-re, located on the southern rim of the Tibetan plateau, spanning the past ca. 30 000 years (30 ka). The study area is characterized by cold climate earth surface processes and aridity due to its altitude and location in the rain shadow of the Mount Everest–Cho Oyu massif and is thus sensitive to climatic and anthropogenic perturbations.

Cosmogenic nuclide and OSL dating in combination with geomorphic mapping, suggests (i) a glacial advance and (ii) highly intensified permafrost and periglacial hillslope processes causing fluvial aggradation of the valley floors of ≥12 m, both broadly coinciding with the last glacial maximum.

We observe formation of a thick (≥50 cm) pedo-complex starting at ca. 6.7 ka before present (BP) and erosional truncation at ca. 3.9 ka BP. Widespread landscape instability and erosion characterize the region subsequent to 3.9 ka and intensifies in the 15th century AD. Several lines of (geo)archaeological evidence, including the presence of pottery sherds, sling-shot projectiles and hammer stones within the sedimentary record, indicate human presence at Su-re since ca. 3.9 ka BP. Merging our Holocene landscape reconstruction with the geoarchaeological evidence, we speculate that the combined effect of Little Ice Age (LIA) cooling and an anthropogenic overuse of the landscape led to climatically induced landscape degradation and ultimately to an anthropogenically triggered ecological collapse in the 15th century. Such a scenario is in-line with regional historical data on declining monastery construction and migration of the ethnic group of the Sherpas.

From an earth surface dynamics perspective, we find that transient landscape processes on the southern rim of the Tibetan plateau are strongly linked to millennial scale changes in the ISM intensity and duration. We identify three types of unidirectional non-linear ISM-landscape interactions. Given that the Tibetan plateau is the largest high-altitude landmass on our planet and our limited understanding of several of the key earth surface processes on the plateau, we pinpoint the need for more long-term (Quaternary scale) empirical data particularly on permafrost and periglacial processes and human-environment interactions.

Abstract ID 836 | Date: 2022-09-14 10:33 – 10:44 | Type: Oral Presentation | Place: SOWI – Lecture hall HS2 |

Pitblado, Bonnie

For the past thirty years I have tried to understand the role of the Rocky Mountains in the initial peopling of the Western hemisphere, as well as how Late Pleistocene and Early Holocene people used the Rocky Mountain landscape. A theme that has pervaded my work has been that to effectively grapple with these issues, one must not conflate the terms “mountain” and “alpine.” That is, mountains are much more than just the windswept expanses above tree line, even if those towering peaks disproportionately capture the imagination of artists, poets, and others.

In fact, in the Southern Rocky Mountains where I have done most of my fieldwork, only a very few archaeological sites have been documented above contemporary tree line. In my experience, those sites tend to be sparse lithic scatters, occasionally accompanied by a chronologically diagnostic projectile point or two. The most ancient sites that have traditionally interested me are rare to non-existent in the alpine zones of my various project regions. And yet, there is something captivating about those highest-of-the-high landscapes, luring me back time after time.

And so it is that at this point in my career, I find myself wanting to better understand what alpine landscapes meant to people throughout the 10,000 or more years that they used them. Did people go there just to hunt, as the lithic scatters and projectile points suggest? Or were ancient people, like me and the artists and the poets, tapping into the sublime power of those places? How can we ever know, with archaeological records that are sparse and located in environments where extractive industries don’t trigger the compliance work that increases site databases elsewhere in the mountains?

I am not sure, but it might help to increase the field of vision. Toward that end, this paper synthesizes data from archaeological sites in the alpine zones of mountains across the western United States—the Rockies, the Cascades, and the Sierra Nevada. I cannot cover such a large area exhaustively, but I cast a wide net, probing site records buried in State Historic Preservation Office (SHPO) and agency databases. This effort is ongoing, and at IMC, I report what I have learned so far about the archaeological signatures of human activities above tree line. I also offer thoughts as to whether those archaeological signatures are more consistent with strictly economic activities or perhaps something more profound than that.

Abstract ID 857 | Date: 2022-09-14 10:44 – 10:55 | Type: Oral Presentation | Place: SOWI – Lecture hall HS2 |

Leigh, David S. (1); Gragson, Theodore (2); Coughlan, Michael (3); Price, Katie (4)

Thousands of years ago mountainsides of the humid-temperate western Pyrenees (Basque region of southern France) were converted from native forests to managed grasslands involving intentional use of fire. The timing of this landscape conversion is evidenced by paleoecological proxies of charcoal, soil magnetic susceptibility, and acrolein/PAHs (geochemical indicators of fire) within stratified slopewash deposits sampled from zero-order watersheds. Radiocarbon chronologies indicate that forest to pasture conversion occurred at 5,000-6,000 years ago in some watersheds and pastures have persisted until the present-day with varying degrees of episodic soil erosion. Our study focused on four hillsides where a well-defined boundary exists between ancient pastures and ancient forests, allowing paired comparisons of soil properties between the different vegetation types. Soil forming factors of climate, topography, parent material, and time were essentially identical in the forests and pastures at each site, isolating variability of the vegetation factor, but the time of soil under grassland vegetation may have varied from site to site. We sampled one complete soil profile and five widely separated core samples of the A horizon from each vegetation type at each site (totaling four soil profiles and 20 A horizon cores from each vegetation type). Analyses included bulk density, pH, plant-available nutrients, organic matter, fulvic versus humic acids, total carbon and nitrogen, amorphous silica, and charcoal content. Results indicate pastured A horizons are about three times as thick as forested soils, contain more organic matter, and have lower bulk densities. These traits favor much greater infiltration and water holding capacities of the pastured soils, which we demonstrated at some of the sites with a compact constant head permeameter (Amoozeemeter). Pastures contain significantly more humic acids than forests, indicating melanization prevails in managed pastures, and pastures sequester significantly more black carbon (charcoal) than forests, resulting from persistent use of fire as a management tool. Pastures also contain greater amounts of amorphous silica, attributable to rapid phytolith production from grasses versus trees. Comparative analysis indicates that the pastures generally have better “soil quality” than the forests, which contradicts the stereotypical paradigm that pastoral land use degrades soil. Thus, long-held land use practices and management decisions in the western Pyrenees facilitate soil sustainability and indeed soil improvement. Ongoing anthropological studies seek to understand how past decisions and methods have shaped this sustainable land use, which promises to inform best land use practices and soil sustainability in other alpine agropastoral regions.

Abstract ID 479 | Date: 2022-09-14 10:55 – 11:06 | Type: Oral Presentation | Place: SOWI – Lecture hall HS2 |

Furlanetto, Giulia (1,2); Abu El Khair, Davide (1); Bertuletti, Paolo (2,3); Comolli, Roberto (1); Maggi, Valter (1); Perego, Renata (2); Ravazzi, Cesare (2)

We present an example of trans-disciplinary research focusing on the last two thousand years of historical ecology and climate in Valmalenco (Italian Central Alps) that combines new co-registered microbotanical data, charcoal analyses and organic nutrients obtained from a peat bog natural archive with ad-hoc explored sources shedding light on cultural history of the site. Furthermore, the time framework benefited from geological mapping, glaciological monitoring, plant surveys, and dendrochronological archives published so far.

The aim of the research is to reconstruct the dynamic interaction between natural and cultural processes in the landscape history. Special attention was addressed to the role of soil geo-ecology, climate changes, and the stepping of pastoralism and of forest exploitation in the last millennium.

The Valmalenco natural history is primary driven by the aridity effects caused by extensive outcropping of serpentinite bedrock. This is an edaphic factor, permanent in the whole postglacial history. On the other hand, dynamic factors active in the last two thousand years, are (i) the cultural fire recurrency intervals affecting the forest composition in the Roman and in the Middle Age, (ii) the increase of human impact in the 15th and 16th centuries, and (iii) the effects of the cold culmination in the Little Ice Age. (iv) Finally, by the early 20th century acme, the post- World War II abandonment of traditional land uses and the last thirty years increasing trend in climate.

Abstract ID 398 | Date: 2022-09-14 11:06 – 11:17 | Type: Oral Presentation | Place: SOWI – Lecture hall HS2 |

Ravazzi, Cesare (1); Bertuletti, Paolo (1); Chiarucci, Alessandro (2); Comolli, Roberto (3); Ferré, Chiara (3); Furlanetto, Giulia (1,3); Morosini, Stefano (4); Perego, Renata (1); Pini, Roberta (1)

An increasing array of observations show that the European mountains are experiencing a period of intensified environmental transformation. However, the timing, rate and amplitude of these changes are only partly detectable by monitoring the contemporary ecosystem dynamics. Too many ecological alterations occurred since Medieval permanent settlements, overriding part of the pristine (i.e. pre-Neolithic) ecosystem structure. The industrial revolution transformed practices of mountain land use, and lead to a fast abandonment since the Second World War. Disentangling the effects of these socio-economic processes from the impact of climate change is paramount to conservation strategies.

We suggest that land use changes observed since the Industrial Revolution (i.e. the last 200 years) may provide the tipping point to connect earlier baselines with the contemporary active pressures on mountain ecosystems. This requires focusing the timing, the rate of change, and the mutual interaction between climate and land-use change in the last 1000 years with a decadal to centennial scale resolution. This framework promises support to the development of the NRRP’s plans helping the biodiversity and the communities living today in the mountain areas of Europe.

We propose a few ideas to overcome the above-mentioned shortages:

1. Expanding palynology towards microbotany, integrating charcoal analysis of sedimentary and soils

2. Assessing changes in pedogenetic processes degree (e.g. brunification vs. podzolization) resulting from changes in land use

3. Connecting proxy records to their spatially explicit boundary conditions e.g. (i) sedimentary basin processes; (ii) modern ecoclimatic elevational gradients

4. Connecting today’s established network of ecological monitoring to the historical record

5. Coupling co-registered abiotic and biotic variables, e.g. organic nutrients, microbotany, dendrochronology, with archivial documents of land-use changes and of climate changes of the last thousand years to meet the requirements of statistical analysis (description, inference and modeling)

The conceptual framework so far discussed will be illustrated by several case studies from the Italian Alps, in the perspective of nature conservation, rewilding, promotion of cultural heritage, and of the sustainable progress of traditional land uses (i) Medieval cultural forest fires eradicating pristine forests; (ii) Late Medieval expansion of the foraging area for pastoralism; (iii) Comparative dynamics of pastures, fertilization, wildlife populations, timberline and glaciers changes; (iiii) Conservation of old-growth larch meadows; (iiiii) ancient drainage and recent warming of peat mires.

Abstract ID 780 | Date: 2022-09-14 11:17 – 11:28 | Type: Oral Presentation | Place: SOWI – Lecture hall HS2 |

Oberklammer, Iris; Gratzer, Georg

Primary forests and old-growth forests are currently receiving increased attention. While the role of such forests in terms of species conservation is increasingly acknowledged in view of the current biodiversity crisis, their potential for carbon storage and thus mitigation of the climate crisis is discussed controversially. The new EU Biodiversity Strategy 2030 calls for strict protection of 10% of EU land cover including all remaining primary and old-growth forests. This sparks new interest in where such forests are located and how they can be characterized or identified. However, current primary forests are the results of (positive and negative) selection processes of the past: only forests that were considered worthy of protection or unworthy of utilization (or both) are remaining in natural or semi-natural states today. These selection processes have been shaped by cultural construction of ideas and concepts. One of these cultural constructions is the concept of primeval forests. We traced back the evolvement of the German word “Urwald” (primary or primeval forest) from the early 19^th century until the 1930s to discuss how primeval forest concepts affect remaining unused forests in the present. For this, we studied descriptions and definitions of “Urwald” in encyclopaedias and forestry journals from the 18^th century onwards. The term Urwald first appears at the beginning of the 19th century. The first lexical description of the term was found in Meyer (1840-1852). There, primeval forest is described in the context of tropical forests, thus originating from the colonial view of exotic wilderness. Early mentions of “Urwald” in forestry journals also refer to forests outside Europe and mourn the loss of their existence in Europe. During the second half of the 19^th century, descriptions of Central European Urwald appear more frequently in the records. Common attributes of these forests are a high deadwood presence and giant stand-dominating trees, as well as the relative (or perceived) absence of past human intervention. Natural disturbances are frequently perceived as agents destroying these forests that subsequently lost their conservation status. We illustrate the cultural construction of primary forests with two examples from forests in the Alps and the Carpathians that were partly converted to managed forest based on the loss of such constituting characteristics. Based on our findings, we argue that awareness of the historic evolvement of concepts and ideas referring to nature can help reflect and improve decisions regarding the future of European forests.

Abstract ID 305 | Date: 2022-09-14 15:15 – 15:17 | Type: Poster Presentation | Place: SOWI – Garden |

Cosatti, Alice

The Fennoscandian forests experienced drastic changes in the 19th century. The high demand for timber during the European industrialization pushed the timber companies towards increasingly remote forest landscapes for resource extraction. This study explores the concept of the so-called timber frontier which seeks to demarcate waves of forest use change, on priorly natural forest land, often inhabited by indigenous populations. The research scope of this study is confined to northernmost Sweden and aims to elucidate the dynamics defining its specific development and pinpoint where the timber frontier ended in this region. The timber frontier reached the uppermost Piteälven watershed area during the end of the 19th century. Historical logging traces of high-grading were searched for during a field survey in Tjeggelvas nature reserve. Independently collected archival data support the findings of the field survey. By analyzing a gradient from the lakeshore to the inner parts of the forest, the end of the timber frontier could be marked out. The results show clearly that logging occurred close to the river and along the lakeshore. The long-term ecological impact, however, remains blurred due to the low impact of historical high-grading extraction practices and the long time period that has passed since then. The historical records indicate that high costs for timber floating and low stand productivity were limiting further exploitation. Furthermore, the timber frontiers’ late arrival and the establishment of the first nature reserves in Sweden overlapped and might be reasons why the timber frontier came to an end in the researched area. Even after one frontier has come to a halt, there is a general tendency for new frontiers of resource extraction to arrive repeatedly on the same lands. Therefore, I suggest that a stronger protection is needed for this unique forest, and that the Sami land use rights are reinforced in order to protect Tjeggelvas nature reserve for future generations.

Abstract ID 473 | Date: 2022-09-14 15:17 – 15:19 | Type: Poster Presentation | Place: SOWI – Garden |

Furlanetto, Giulia (1,2); Bertuletti, Paolo (2,3); Bondesan, Aldino (4); Cadioli, Giovanni (4); Morosini, Stefano (5,6); Novellino, Massimo Domenico (2,3); Perego, Renata (2); Pini, Roberta (2); Ravazzi, Cesare (2)

Rapid melting of glaciers caused by increasing global temperature is dramatically changing the way we see and experience alpine environments. Barren terrains take the place of former thick ice covers, woody vegetation settles at unprecedented altitudes and remnants of past lives and events come to light. High-altitude areas in the Italian Alps hosted violent battles during the so-called “White War”, i.e. the World War I fighting in cold and harsh alpine terrains. Perfectly preserved remains of those events and of their actors frequently appear above 2000 m, as a consequence of ice melting; soldiers’ personal belongings and weapons tell us the flow of life and war in hostile environments.

The barrack on Mount Scorluzzo (3095 m asl) was carved into the rock by Austro-Hungarian soldiers. The site was inhabited from June 1915 to November 1918, when Italians took over the site abandoned by the enemy troops. The barrack entrance was freed from ice in 2015, allowing the first people to enter after almost a century. All the materials retrieved will be the core of the exhibition in a new Museum to be opened in Bormio in 2022.

As part of a research and dissemination project on the historical and military events on the Alpine Front between 1914-1918, we analyzed micro- and macrobotanical remains preserved in ice inside the Scorluzzo barrack. We collected discrete ice samples from local domestic habitats (the shelter floor, the table used to eat meals, mattresses, a fur) and a 1 meter-high ice column, considered as the stratigraphical archive of the shelter. Coupled palynological and macrobotanical analysis explore biodiversity preserved in ice and use it as a proxy for processes of accumulation of organic and mineral particles. Most of the plant material found in the shelter was deliberately brought for every-day use and has no relationship with alpine vegetation. Cereal stems were used to stuff mattresses and pillows, where abundant pollen was also found. Many samples revealed the presence of eelgrass (Zostera marina), posing specific questions on the supply chain of the Austro-Hungarian army. Pollen from woody vegetation is abundant in the fur, which acted like a trap of microscopic particles across altitudinal vegetation belts. Pollen also comes from snow and ice melting, with water percolating inside the shelter. Botanical data will be later on compared with the results of DNA and entomological analysis, for a better understanding of dispersal and accumulation processes.