ICG2022-16

ICG2022
Biogeomorphology and Wetlands 

The emergence of life has strongly influenced Earth surface processes and left distinctive markers in the geological record. Vegetation and animals affect many aspects of the Earth’s ‘critical zone’ from the plot to the landscape scale, including weathering, hillslope, fluvial and aeolian dynamics, while geomorphological processes have profound impacts on ecological dynamics. This knowledge is increasingly used in environmental management projects (e.g. wetland restoration) but many gaps remain in understanding and the ability to quantify timescales and rates of change. This session welcomes contributions from researchers using experimental, field, and/or modelling approaches. Topics may include, inter alia:
i. vegetation and animal influences on geomorphic processes;
ii. chronologies of biogeomorphological change;
iii. trajectories of future landscape change in biodiversity ‘hotspots’ (e.g. Ramsar wetlands, tropical rainforests).

Conveners: Heather Viles, Stephen Tooth, Dov Corenblit, Messias Modesto dos Passos
Orals
| Mon, 12 Sep, 17:00–19:00|Room Sala Sofia-C2B
Poster
| Attendance Mon, 12 Sep, 16:30–16:45 | Display Mon, 12 Sep, 09:00–Tue, 13 Sep, 19:00|Poster area

Orals: Mon, 12 Sep | Room Sala Sofia-C2B

Chairpersons: Stephen Tooth, Dov Corenblit, Heather Viles
17:00–17:15
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ICG2022-626
Larissa A. Naylor, Mairi Mac Arthur, Jim D. Hansom, and Michael Burrows

 

 

The interplay between topographic complexity (aka. Geomorphology) and ecological communities is of growing interest by ecologists in the rapidly growing field of eco-engineering. This work brings a biogeomorphological lens to these studies, examining the influence of lithology and different types of geomorphic features found on rocky coasts. Geomorphic features such as pools, pits, cracks, crevices and ledges vary spatially and are closely linked to geological contingency and this in turn effects on rocky shore biodiversity (species richness, abundance and community composition). We studied these interactions in four ways: (1) a comparative study of rock mass and rock material properties at four sites in Scotland to establish the role of rock type and geomorphic feature type on ecology, (2) a comparison of two lithologies (limestone and sandstone) at the same site to identify the importance of rock type and geomorphic feature type on ecology (3) a further study integrating Terrestrial Laser Scans of geomorphic complexity overlain with ecological variables (species richness and mobile species abundance) to create a model of rocky shore species density in relation to geomorphic features and (4) a study of species density at the Glamorgan coast, Wales, comparing the effects of one geological factor – low and high density jointing (crevices and cracks) within the same bed layer. Species richness and abundance was found to significantly differ with rock type and the presence of geomorphic features on each shore, with deep pools being the optimal habitat type with regards to these ecological variables. The higher abundance of species in pools and crevices (depending on site) highlights that the presence of larger-scale features such as pools, crevices and ledges are important for the survival of intertidal species as crevices can function as refuge from predators and wave stress and pools can reduce desiccation stress at low tide.  Features that performed well in attracting higher species richness or abundance, which were ledges, deep pools and crevices, were examined in greater depth. Pits were also examined due to their common use as retrofitted ecological enhancement on coastal infrastructure (Firth et al., 2014b; Hall et al., 2018; Loke et al., 2017; Martins et al., 2010), where generalised linear models were used to examine the significance of width, depth and water holding % on species richness and abundance for each feature, allowing us to make quantitatively based assessment of which feature types are most ecologically optimal.  This greater provision of habitat through increased surface area, increased protection and greater variety of surface topography suggest that complex rock types and associated landform features/geomorphic features are more likely to have higher species richness and abundance, particularly when compared to adjacent areas of shore platforms that lack this geomorphic complexity.  These natural rocky shore biogeomorphology findings can be used to optimise future eco-engineering designs, enriching the design process and considerations for improving ecological outcomes on urbanised coasts. It also allows us to bring in geomorphic features, and thus rocky shore geomorphology into urban landscapes, enriching human interactions with geomorphology as well as ecology.

How to cite: Naylor, L. A., Mac Arthur, M., Hansom, J. D., and Burrows, M.: Quantifying natural rocky shore biogeomorphic interactions to inform eco-engineering designs for urban coasts. , 10th International Conference on Geomorphology, Coimbra, Portugal, 12–16 Sep 2022, ICG2022-626, https://doi.org/10.5194/icg2022-626, 2022.

17:15–17:30
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ICG2022-425
Yong Zhou, Yi Zhou, Hongyu Liu, Yufeng Li, Cheng Wang, and Alan Wright

As an important indicator of wetland hydrology, hydrogeomorphic conditions clearly indicate the coupling relationships between hydrology, landscape, and habitat. Aiming at problems of small-scale recovery and lack of systematic guidance in current coastal wetland restoration research, this study put forward a coastal wetland restoration system based on the hydrogeomorphic spatial unit. The spatial units of the hydrogeomorphic model were defined according to the regional background in Yancheng coastal wetland, and the changes in land cover patterns from 1980 to 2019 were analyzed. Then, based on the importance and potential for restoration, the key restoration areas were determined and then the dynamics change characteristic of S. salsa salt marsh boundary at the natural state was summarized. It showed that the ecosystem function in the region was basically stable from 1980 to 1998, and the boundary of the S. salsa salt marsh in each key restoration area showed dynamic stability or expansion to the sea. By 2019, with the construction of reclamation and coastal engineering, the hydrogeomorphic conditions in the region changed significantly. In addition to the continuous expansion of S. alterniflora marshes, other natural wetland types almost disappeared and transformed into aquaculture ponds or farmland. Based on those above, the study discusses the overall restoration modes of different hydrogeomorphic spatial units from two aspects of active restoration and passive restoration and puts forward systematic restoration measures in combination with the current characteristics of key restoration areas, forming a technical framework for coastal wetland restoration with practical guiding significance.

How to cite: Zhou, Y., Zhou, Y., Liu, H., Li, Y., Wang, C., and Wright, A.: Coastal wetland restoration based on hydrogeomorphic space units ——Taking the coastal wetland of Yancheng, Jiangsu as an example, 10th International Conference on Geomorphology, Coimbra, Portugal, 12–16 Sep 2022, ICG2022-425, https://doi.org/10.5194/icg2022-425, 2022.

17:30–17:45
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ICG2022-248
Diego Alves de Oliveira, Cristina Helena Ribeiro Rocha Augustin, Paulo Roberto Antunes Aranha, Tom Dargie, Cristina Persano, and Rubens Martins Moreira

Wetlands represent an excellent example of the interface between lithosphere, atmosphere, and hydrosphere. Despite being distributed throughout the planet, the pace of their destruction has increased, especially since the 1970s. In tropical regions, they may be associated with floodplains or topographical depressions permanently or temporarily flooded, with different size configurations and hydrogeomorphological dynamics. 

Among the major river systems in South America, the São Francisco river basin, located entirely in Brazilian territory, has strategic importance in providing energy and water resources to the semi-arid northeast region, with about 30 million people. In it, there are small wetlands, considered in extension, but with great frequency, located in areas of headwaters and floodplains, mainly. 

In this basin, the Pantanal of the Pandeiros watershed synthesizes the main environmental impacts are existing in the São Francisco River basin. For example, high frequency of accelerated linear water erosion processes, known locally as voçoroca (gullies), deforestation since the 1970s, which continues for the production of charcoal, the presence of a small hydroelectric plant, the reduction of water flow since the 1990s and the intense dynamics of sediment transport. 

In the São Francisco river basin, there is an abundance of rocks and regolith formed by siliciclastic material, where their contribution to the dynamics of wetlands is still not well understood. The Pantanal of the Pandeiros wetland located in the floodplain of São Francisco River has a singular occurrence. Where it is at risk of lose to provide environmental services, through silting, the Pantanal of the Pandeiros River has complex hydrogeomorphological dynamics from the delimitation of a depressed area concerning its surroundings, marked by slope rupture, with a contribution to its flooding, the increase, and maintenance of the São Francisco river level during flood pulses, determining longitudinal dynamics in the wetland. 

Were mapped four different hydrogeomorphologic zones from a multiproxy approach: 

Isotopic tracers 2H and 18O, together with piezometers, demonstrate connections between the wetland and the floods of the Rivers São Francisco and the Pandeiros, strongly influenced by past and current geomorphological forms and processes. 

Raster images of digital elevation models and satellite, during flood pulses, plus ground-penetrating radar and analyses of geocoverages records ranging from environments predominantly sandy to clayey from upstream to downstream, respectively. Levels sandy material up to 3m deep, followed by a layer of pebbles and paleochannels. 

Sediments collected up to 150 cm deep date back to 3,246 years B.P., with a predominance of humid environment, via analysis of 14C and 13C. The average denudation rate in the last 1.5 million years, using 10Be, a high contribution of sediments were identified, which circulate in the basin, coming from specific regions, where erosive processes are predominant, such as gullies. 

How to cite: Alves de Oliveira, D., Helena Ribeiro Rocha Augustin, C., Roberto Antunes Aranha, P., Dargie, T., Persano, C., and Martins Moreira, R.: Contribution of Geomorphology to the dynamics of small continental wetlands with temporary flooding: the case of the Pantanal of the Pandeiros River, Brazil , 10th International Conference on Geomorphology, Coimbra, Portugal, 12–16 Sep 2022, ICG2022-248, https://doi.org/10.5194/icg2022-248, 2022.

17:45–18:00
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ICG2022-591
Joanna Zawiejska

Following centuries of absence, beavers were successfully introduced to the Polish Carpathians in the 1980s and have since colonized watercourses of different size, degree of human modification and ecological status. In the foreland of the high-mountain Tatra massif, beaver colonization in the last 10 years has been particularly rapid in but its success, patterns and effects vary between highly dynamic large rivers with extensive riparian areas and smaller streams. In large rivers, beaver activity is focused on modification of adjacent floodplain areas, extensive use of vegetated islands, and ‘creative’ adaptation and use of large wood accumulations and particularly channelized structures in heavily changed reaches. In smaller, low-gradient streams, morphological changes introduced by beavers can be dramatic compared to channel size but largely depend on underlying substrate and interactions with local human population (including land ownership). In most cases, unrestricted beaver activity indicates the potential of these animals for rapid and spontaneous restoration of modified rivers and streams; however, its long-term impact on riparian forests should be monitored.

How to cite: Zawiejska, J.: Effects of beaver expansion in semi-natural and modified watercourses in the Tatra Mts foreland, Polish Carpathians:  implications for river restoration., 10th International Conference on Geomorphology, Coimbra, Portugal, 12–16 Sep 2022, ICG2022-591, https://doi.org/10.5194/icg2022-591, 2022.

18:00–18:15
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ICG2022-297
Thandeka Ndlela, Heinz Beckedahl, Althea Grundling, and Piet-Louis Grundling

The Malolotja Nature Reserve is located on the great southern African escarpment which comprises the ecotone between the highveld and middleveld. The reserve has several streams, rivers and wetlands with the most significant being the Malolotja wetland which, during a reconnaissance undertaken in 2018, showed it to contain significant peat deposits. This is the first scientific record of peatlands within the country. While it is widely acknowledged that the primary characteristic of peatlands is their high organic content, their ability to retain water and therefore their hydrological properties, control their existence and development. The first hydrology of the peatland was investigated using a network of 10 wells, 18 piezometers and 1 rain gauge; installed in one transect at specific monitoring points within the peat. Monitoring of various hydrological parameters was initiated on April 14th, 2019 and ceased on May 31st, 2020. Monitoring of water levels, electrical conductivity, water temperature, rainfall and air temperature was conducted weekly. 

The findings suggest that the northern and central areas of the peatland have a shallow water table, high electrical conductivity and low water temperatures, while the peripheral areas have a deeper water table, lower electrical conductivity and higher water temperatures. The dominant water sources for the peatland appear to be rainfall, groundwater, recharge from the central stream back into the peat, and slope seepage. The peatland also appears to be a good sink for ammonium, with a pH range varying from slightly acidic to slightly basic. Without a detailed mineralogical study of the underlying bedrock, a geological contribution (though appearing unlikely) cannot be completely verified out. It is in this context that further analysis of the peat itself is currently underway, and it is hoped that this will provide a better understanding of how water moves within the system. 

How to cite: Ndlela, T., Beckedahl, H., Grundling, A., and Grundling, P.-L.: Understanding the hydrology of a Swati peatland: A case study of Malolotja Nature Reserve, Eswatini, 10th International Conference on Geomorphology, Coimbra, Portugal, 12–16 Sep 2022, ICG2022-297, https://doi.org/10.5194/icg2022-297, 2022.

18:15–18:30
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ICG2022-95
Martin Evans, Tim Allott, Emma Shuttleworth, Donald Edokpa, Tim Howson, David Milledge, Joseph Holden, Salim Goudarzi, Martin Kay, Joe Rees, Adam Johnston, Tom Spencer, Ikenna Osumgborogru, Richard Grayson, Jamie Freestone, and Matt Scott-Campbell

The dramatic badland landscapes of severely eroded peatlands represent significant degradation of the ecosystems, which when intact, provide a range of regulating ecosystem services including carbon sequestration and runoff regulation. Increasing efforts are being made to restore these landscapes through re-vegetation and gully blocking. Restoration has been driven by the aims of restoring biodiversity and carbon storage but the transformation of hillslopes and channels also has significant impacts on hillslope runoff. This paper reports on a major project from the uplands of the UK which has been studying the generation of hillslope runoff in restored peatlands and the potential to optimise restoration approaches to mitigate downstream flood risk. Peatlands are highly productive of runoff so that these approaches have the potential to deliver multiple benefits including Natural Flood Risk management for headwater communities.

Our work has demonstrated that whilst static storage of water behind gully blocks is one component of the NFM benefit, dynamic storage on hillslopes during storm events is enhanced by increased surface roughness in restored catchments and is the larger component of the overall NFM benefit. Gully blocks with pipes or slots which enable drawdown between storms maximise static storage whilst the planting of sphagnum moss dramatically increases dynamic storage on the hillslopes.

Taken together these data support the potential role of peatland restoration in NFM schemes and suggest that restoration of gully-eroded peatlands can deliver flood protection in headwater communities alongside wider benefits.

How to cite: Evans, M., Allott, T., Shuttleworth, E., Edokpa, D., Howson, T., Milledge, D., Holden, J., Goudarzi, S., Kay, M., Rees, J., Johnston, A., Spencer, T., Osumgborogru, I., Grayson, R., Freestone, J., and Scott-Campbell, M.: Restoring gullied peatlands: Natural Flood Risk Management benefits from landscape scale restoration of the 'badlands of Britain', 10th International Conference on Geomorphology, Coimbra, Portugal, 12–16 Sep 2022, ICG2022-95, https://doi.org/10.5194/icg2022-95, 2022.

18:30–18:45
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ICG2022-202
Timothy Beach, Sheryl Beach, Samantha Krause, Byron Smith, and Colin Doyle

Our recent work shows that wetlands in Mesoamerica are declining rapidly in recent decades from agricultural expansion and deforestation.  We have also shown the long human use of these wetlands over at least the last 2,000 years and possibly since the middle Holocene through several studies in Belize, Mexico, and Guatemala.  In this paper we use high resolution surface mapping based on Lidar that covers more than 500 square kilometers of forested areas with field-based biogeomorphological and archaeological verification to study the formation of Pre-Columbian indigenous wetland agricultural complexes. We present three examples from both our well-studied and newly studied sites in a range of wetland settings from perennial to seasonal riverine and karst depressions under different water chemistries.  The first well-known example is from the fluviokarst Rio Bravo Watershed in Belize that provides an example of how wetlands formed over the last two millennia under starkly different chemical conditions from low to high solute loads (mostly sulfate and calcium carbonate).  Second, we consider little known wetland canal and field systems in the seasonal, karst, upland depressions in Guatemala. Third, we consider more little-known riparian wetlands of the coastal Plain of Tabasco and Campeche.  For each region, we consider geomorphologic factors such as water and soil chemistry, biological factors such as vegetation change, and the evidence we have, from excavations, of human management of these systems.  We also compare more ‘natural’ and more anthropogenic models for their formation.  Next, we provide a new, updated estimate of the areal extent and human importance of these wetland complexes.  Finally, we consider how our findings are relevant for ‘natural’ and polycultural wetland restoration.  

How to cite: Beach, T., Beach, S., Krause, S., Smith, B., and Doyle, C.: Biogeomorphological Wetland Formation and Long-term Human Interactions in Mesoamerica, 10th International Conference on Geomorphology, Coimbra, Portugal, 12–16 Sep 2022, ICG2022-202, https://doi.org/10.5194/icg2022-202, 2022.

18:45–19:00
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ICG2022-606
Renée Grundling, Heinz Beckedahl, and Michael Loubser

The influence of humans on the environment is becoming more pronounced with increase in, particularly, urban population. The imprint humans leave behind is so pronounced that a new geological epoch, the Anthropocene, has been created to accommodate the effects of direct and indirect anthropogenic influences. Anthropogeomorphology is the study of how humans modify and create landforms and landform processes. Humans deliberately change the distribution of water resources, modifying flow patterns, damming, draining areas retaining water and extracting underground water sources such as manipulation of fluvial environments by constructing structures to alter their hydrology – historically, from ancient aqueducts to modern hydraulic and civil engineering.
Wetland type and functioning result from driving forces such as geomorphology, hydrology and biological processes (e.g., colonization, competition, decomposition). The hydrology of wetlands in semi-arid interior regions of southern Africa where evapotranspiration exceeds precipitation is often dependant on catchment surface water flows, sustained groundwater and hillslope intermediate flows which is reflected in vegetation diversity and often mirrors the transformation of a catchment. Wetlands are generally seen as natural geomorphological features but can be both formed and modified due to human activities, therefore the subject of anthropogeomorphology. These activities can be both direct, restoration projects for example, and/or indirect in nature. Indirect drivers of anthropogeomorphological wetlands are broad and not properly documented and can range from consequences of urbanisation to agricultural irrigation runoff.
The aim of this research is to investigate the role of anthropogenic wetland formation in the realm of anthropogeomorphology in South Africa and to assess their distribution and current standing in wetland classification systems. Methods include categorizing anthropogeomorphological wetlands identified by comparing land-use, development, and vegetation cover changes by using GIS. The characteristics of these sites are further analysed based on category and compared to the characteristics of natural wetlands in its vicinity.

Keywords: Wetlands, geomorphology, anthropogeomorphology

How to cite: Grundling, R., Beckedahl, H., and Loubser, M.: Anthropogeomorphological Wetlands in South Africa, 10th International Conference on Geomorphology, Coimbra, Portugal, 12–16 Sep 2022, ICG2022-606, https://doi.org/10.5194/icg2022-606, 2022.

Display time: Mon, 12 Sep 09:00–Tue, 13 Sep 19:00

Poster: Mon, 12 Sep, 16:30–16:45 | Poster area

Chairpersons: Stephen Tooth, Dov Corenblit, Heather Viles
P76
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ICG2022-216
Matthieu Prugne, Thomas Buffin-Bélanger, Maxime Boivin, and Dov Corenblit

Riparian areas are important ecosystems that need to be restored and protected in the Anthropocene era. In Quebec, Canada, conservation laws and management strategies focus on ecological services provided by riparian communities, such as erosion and flood control, carbon sequestration, and pollutants filtration. However, there is a need to incorporate fluvial biogeomophological approaches to improve our understanding of those systems. Biogeomorphology explores both the impacts of flood regime and disturbances on plant structure and composition and the role of plant communities in altering hydrosedimentary processes. Approaches anchored in biogeomorphology have proven to be efficient to understand interactions and feedbacks between fluvial dynamics and plant ecology in many contrasted environments, from temperate to arid regions and from small streams to large rivers. However, those approaches have never been applied to rivers disturbed by ice dynamics. Ice jams and mechanical breakups are known to disturb fluvial systems, both geomorphologically and ecologically. Moving ice during breakups has the potential to severely erode banks and transport sediment, thus destroying riparian habitat and disturbing plant succession dynamics. Feedback dynamics between plants and rivers are thus obviously affected by ice disturbances regime. There is a need to understand how fluvial biogeomorphic systems respond to such disturbances to assess better management strategies and improve prevision models in a context of climatic change. In this poster, we expose a research project aiming at conceptualizing how ice disturbances regime controls the biogeomorphic interactions in two rivers located in eastern Quebec, Canada. To do so, analyses will be held in three distinct spatiotemporal scales: 1) decennial biogeomorphological trajectories, 2) plant community structure and composition on distinct fluvial landforms and 3) functional traits of ice-disturbed indicator species.

How to cite: Prugne, M., Buffin-Bélanger, T., Boivin, M., and Corenblit, D.: Biogeomorphic interactions in ice-driven fluvial hydrosystems, 10th International Conference on Geomorphology, Coimbra, Portugal, 12–16 Sep 2022, ICG2022-216, https://doi.org/10.5194/icg2022-216, 2022.

P77
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ICG2022-192
Derek Martin, Sarah Praskievicz, Josh Platt, and Stephanie Stephens

Coastal Plain rivers represent sites of extraordinary ecological and biogeochemical importance for many reasons. One such reason is that large wood (LW), which serves to regulate sediment and biogeochemical processes as well as enhance geomorphic complexity, is readily transported and deposited in such systems.  However, most research on LW dynamics has taken place in low order, montane river systems and thus little is known of LW dynamics and the interactions of LW and channel morphology in higher order, coastal plain river systems. One of the challenges to understanding wood dynamics in such systems is the ability to locate and quantify subaqueous wood. This research, funded by the National Science Foundation, presents a case study of the Lumber River, an Atlantic coastal plain blackwater river located in North Carolina, USA in which we investigate wood dynamics. Specifically, we use a SONAR-based approach to mapping subaqueous wood in association with channel bedform. Using a canoe/kayak mounted SONAR unit we develop high resolution images of bed morphology and sub-aqueous wood, and report on the results of remote sensing algorithms that aim to extract wood geometry/volume, which is then assessed within the context of the bed morphology. This will help us gain a better understanding of the relationships between channel morphology and wood transport/deposition in low-gradient, high order river channels, and provide more accurate inputs to wood/carbon transport models.

How to cite: Martin, D., Praskievicz, S., Platt, J., and Stephens, S.: Using SONAR to Investigate Relationships Between Fluvial Wood and Channel Bedform in a Low Gradient, Coastal Plain River, 10th International Conference on Geomorphology, Coimbra, Portugal, 12–16 Sep 2022, ICG2022-192, https://doi.org/10.5194/icg2022-192, 2022.

P78
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ICG2022-396
Chenxi Zhong and Takashi Oguchi

Shallow landslides are instability events that lead to mass wasting of soil and vegetation in sloping areas and are commonly triggered by intense rainfall. Since vegetation is an important factor influencing the occurrence of rainfall-triggered shallow landslides and reduces the likelihood of landslides through different hydromechanical mechanisms, conducting in-depth research in this field for disaster risk management is meaningful. Investigating vegetation recovery processes after shallow landslides can provide significant insights for improving future disaster habitation works. However, vegetation recovery processes after shallow landslides and their influencing multivariate factors are not well known. Therefore, the objective of this study is to clarify the effects of geology and topography on vegetation recovery after shallow landslides in two research areas, the Shobara district, Hiroshima Prefecture, Japan, and the Obara district, Aichi Prefecture, Japan. Image analysis of historical aerial photographs was used to extract landslide-affected areas. Temporal changes in vegetation-condition indices were accessed from satellite imagery. GIS tools were used to extract topographic and geological indices. The relationships among those factors were quantified using a multivariate analysis of variance. Time series analysis was conducted by using the seasonal autoregressive integrated moving average. The change in time series, climate data, topographic, and geological characteristics were incorporated into a framework for mapping and modeling vegetation recovery. The results have quantitatively revealed both similarities and differences in vegetation recovery between the two areas in relation to geomorphological and geological conditions.

How to cite: Zhong, C. and Oguchi, T.: Effects of topography and geology on vegetation recovery after shallow landslides, 10th International Conference on Geomorphology, Coimbra, Portugal, 12–16 Sep 2022, ICG2022-396, https://doi.org/10.5194/icg2022-396, 2022.

P79
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ICG2022-6
François Bétard

Insects are the largest and most diverse group of living organisms on Earth, playing a critical but underestimated role as agents of geomorphic change. Burrowing insects create micro-scale landforms such as subterranean tunnels and surface mounds and, by this way, have a substantial impact on hydrology, soil erosion and sediment transfer at a wider landscape scale. On another side, geomorphic environments and landform heterogeneity strongly influence insect distribution and diversity. The aim of this presentation is to explore the reciprocal links between geomorphology – the study of landforms – and entomology – the study of insects –, beyond the well-known and classical considerations about the role of social ants and termites as geomorphic agents and ecosystem engineers. Five types of insect-landform relationships are examined in this scope: (1) insect ethology and geomorphic processes, (2) insect ecology and geomorphic environment, (3) insect diversity and landform heterogeneity, (4) insect decline/invasion and Anthropocene geomorphology, and (5) insect conservation and landform management. The evidence of reciprocal links between insects and landforms lays out the contours of an Insect Zoogeomorphology – or Entomogeomorphology – as a potential subfield of biogeomorphology to be developed further. Such zoogeomorphological studies should contribute to a better understanding of the importance of insects in Earth surface processes and landforms, with many useful applications in environmental management projects and strategies (e.g., restoration projects of grasslands and wetlands, translocation strategies for the conservation of species and associated biogenic landforms…).

How to cite: Bétard, F.: Insect zoogeomorphology: Exploring the links between geomorphology and entomology, 10th International Conference on Geomorphology, Coimbra, Portugal, 12–16 Sep 2022, ICG2022-6, https://doi.org/10.5194/icg2022-6, 2022.

P80
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ICG2022-541
Daniel Germain, Jenny Luciano, and Jean-François MIlot

In eastern Canada, the retreat of the Laurentide Ice Sheet over the last ~12,000 years, corresponding to the Holocene – the present interglacial period - has left immense quantities of surficial sediments over the entire territory. Today, these sediments still represent in a very variable way in time and space, an abundant source of fine and coarse sediments for fluvial and coastal systems and, to a lesser extent, for mass movements. Although the geomorphological dynamics of landscapes have been studied for a long time, biotic factors and particularly animals have not yet been deeply studied in terms of their interactions with the abiotic world. The present contribution sheds new light on the geomorphological impact of the trophic relationship between red fox (Vulpes vulpes) and bank swallow (Riparia riparia). Indeed, the predator-prey relationship between these two species and their behaviours accentuate the erosion of sandy cliffs where swallows nest, because by red fox makes foraging pits to reach the eggs and young swallows. Even if our data based on a four-year survey indicate low rates of cliff recession related to biotic effects compared to the impact of extreme hydrological events, it remains that they contribute to the sediment budget at short and long term. In that regard, we have documented over the last four years from an original point of view the common relationship predator-prey with a geomorphic perspective and propose to discuss this topic with significant field dataset.

How to cite: Germain, D., Luciano, J., and MIlot, J.-F.: The predator-prey relationship from a zoogeomorphic perspective: An example with red fox (Vulpes vulpes) and bank swallow (Riparia riparia), Canada, 10th International Conference on Geomorphology, Coimbra, Portugal, 12–16 Sep 2022, ICG2022-541, https://doi.org/10.5194/icg2022-541, 2022.

P81
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ICG2022-203
Timothy Baxter, Sam Woor, and Heather Viles

Moles (small insectivorous mammals of the family Talpidae) are widespread across the Northern Hemisphere, with their ranges covering Europe, Asia, and North America. The presence of these subterranean mammals is easily detected through the mounds, or molehills, which they construct as surface bioproducts of tunnel systems excavated underground. These bioconstructions created by moles indicate they may play geomorphologically important roles in sediment systems. The bioturbation of soils by moles has also been shown to be ecologically important as they mix nutrients and aerate soils, suggesting that their role in local sediment systems may be intrinsically linked to ecosystem functioning. However, compared to other fossorial animals (species which dig, e.g. ants, rabbits, badgers etc.) the impact of moles as direct and indirect biogeomorphic agents and their role as ecosystem engineers is poorly understood. For instance, relatively little is known about the impact of moles on microtopography, surface runoff and erosion rates, vegetation cover, and soil properties.

By examining molehills created by the European mole (Talpa europaea) in Oxfordshire, UK, we provide a quantitative assessment of how these landforms evolve over time and space. Following the mapping of molehills at selected sites and regular monitoring over a 6-month period, this study estimates the rate of sediment movement caused by mole activity. We also examine what happens to molehill morphology post-construction, as well as the characteristics of soil bioturbated by moles vs. non-bioturbated soil and the potential impact of molehills on local biodiversity.

How to cite: Baxter, T., Woor, S., and Viles, H.: The geomorphic work of the European mole and its role as an ecosystem engineer. A case study from Oxfordshire, southern England., 10th International Conference on Geomorphology, Coimbra, Portugal, 12–16 Sep 2022, ICG2022-203, https://doi.org/10.5194/icg2022-203, 2022.

P82
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ICG2022-200
Emma Shuttleworth, Martin Evans, Allott Tim, Kay Martin, Johnston Adam, Donald Edokpa, Rees Joe Lake, Milledge David, Goudarzi Salim, Holden Joseph, Pilkington Michael, and Spencer Tom

The UK supports 15% of the world’s blanket peat cover but much of this vital resource is significantly degraded. In damaged peatlands runoff is quickly evacuated from hillslopes across bare peat surfaces and through erosional gullies, exacerbating downstream flooding. The restoration of damaged UK peatlands is a major conservation concern, and landscape-scale restoration by revegetation and damming of gullies is extensive in areas of upland Britain. There is increasing evidence that the restoration techniques can significantly slow the flow of water in addition to providing other ecosystem service benefits. More recently, focus has shifted from stabilising eroding surfaces to the reintroducing Sphagnum moss as part of multi-benefit restoration initiatives.

This paper reports the results of long-term post-restoration monitoring on the Kinder Plateau in the southern Pennines of the U.K. Two sites were revegetated using lime-seed-fertiliser-mulch in 2011 and one of the sites was also gully blocked in 2012 and had a further phase of restoration in the form of intensive Sphagnum planting in 2015. A third unrestored control site was also monitored. We present post-intervention biogeomorphological changes spanning 10 years, showing the long-term trajectories of vegetation cover, runoff, sediment production, and water table.

The trajectories of recovery for different functions differ in form and rate. At both treatment sites, vegetation cover increases rapidly then slows as full cover is approached. Sediment production is quickly reduced to levels comparable to intact peatlands within two years and bare peat cover becomes negligible after ~7 years. Key runoff metrics (e.g. peak discharge and lag time) show similar immediate step changes as a result of increased surface roughness from the rapid vegetation expansion, followed by more gradual improvements as species richness develops through time.  The addition of gully blocking enhances the impact of re-vegetation alone, amplifying the step change, but there are no further benefits apparent in the longer-term trajectory. The introduction of Sphagnum provides further roughness, leading to marked increases in lag times and attenuation of runoff. There is also preliminary evidence that the Sphagnum inhibits surface drying, providing resilience to future climatic and anthropogenic stressors.

This study provides the first evidence that the reintroduction of Sphagnum in degraded headwater peatlands can provide additional Natural Flood Management benefits compared to standard restoration techniques aimed at stabilising eroding surfaces. We also show that water table recovery is not at odds with flow attenuation. We also note the importance of control assessing the impact of restoration interventions and the need for investment in longer-term (>10 year) monitoring to better understand the recovery of restored peatlands.

How to cite: Shuttleworth, E., Evans, M., Tim, A., Martin, K., Adam, J., Edokpa, D., Joe Lake, R., David, M., Salim, G., Joseph, H., Michael, P., and Tom, S.: A ten-year trajectory of change in a restored blanket peatland: implications for natural flood management, 10th International Conference on Geomorphology, Coimbra, Portugal, 12–16 Sep 2022, ICG2022-200, https://doi.org/10.5194/icg2022-200, 2022.