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The paper by E. Méndez-Quintas et al. (2020) aims to give an interdisciplinary overview of the lower Miño River terrace record in NW Iberia by combining geological and archaeological data. The authors also pretend to re-interpret the geological-geomorphological evolution of this river by presenting new data and by comparing them to data published in our five related papers. However, a wrong interpretation of the data they present as well as incorrect and selective citations of ours lead to the production of a publication containing numerous errors. The most flagrant ones are the mapping of fluvial terraces on one side of the river only and an incorrect interpretation of the sedimentological information used to correlate terrace remnants along-river. This results in incorrect longitudinal profile reconstructions and an improper proposal of the evolution of the Miño terraces that is even contradicted by the data they present. On the upside, the ages of the Porto Maior terrace site published by these authors confirm our previously published longitudinal profile reconstructions and evolutionary model of the Miño valley.

Combining field reconstruction and landscape evolution modelling can be useful to investigate the relative role of different drivers on catchment response. The Geren Catchment (~45 km

The Gediz River, one of the principal rivers of Western Anatolia, has an extensive Pleistocene fluvial archive that potentially offers a unique window into fluvial system behaviour on the western margins of Asia during the Quaternary. In this paper we review our work on the Quaternary Gediz River Project (2001–2010) and present new data which leads to a revised stratigraphical model for the Early Pleistocene development of this fluvial system. In previous work we confirmed the preservation of eleven buried Early Pleistocene fluvial terraces of the Gediz River (designated GT11, the oldest and highest, to GT1, the youngest and lowest) which lie beneath the basalt-covered plateaux of the Kula Volcanic Province. Deciphering the information locked in this fluvial archive requires the construction of a robust geochronology. Fortunately, the Gediz archive provides ample opportunity for age-constraint based upon age estimates derived from basaltic lava flows that repeatedly entered the palaeo-Gediz valley floors. In this paper we present, for the first time, our complete dataset of 40Ar/39Ar age estimates and associated palaeomagnetic measurements. These data, which can be directly related to the underlying fluvial deposits, provide age constraints critical to our understanding of this sequence. The new chronology establishes the onset of Quaternary volcanism at ∼1320ka (MIS42). This volcanism, which is associated with GT6, confirms a pre-MIS42 age for terraces GT11-GT7. Evidence from the colluvial sequences directly overlying these early terraces suggests that they formed in response to hydrological and sediment budget changes forced by climate-driven vegetation change. The cyclic formation of terraces and their timing suggests they represent the obliquity-driven climate changes of the Early Pleistocene. By way of contrast the GT5-GT1 terrace sequence, constrained by a lava flow with an age estimate of ∼1247ka, span the time-interval MIS42 – MIS38 and therefore do not match the frequency of climate change as previously suggested. The onset of volcanism breaks the simple linkage of terracing to climate-driven change. These younger terraces more likely reflect a localized terracing process triggered by base level changes forced by volcanic eruptions and associated reactivation of pre-existing faults, lava dam construction, landsliding and subsequent lava-dammed lake drainage. Establishing a firm stratigraphy and geochronology for the Early Pleistocene archive provides a secure framework for future exploitation of this part of the archive and sets the standard as we begin our work on the Middle-Late Pleistocene sequence. We believe this work forms a benchmark study for detailed Quaternary research in Turkey.

Grote Houw is één van de vier locaties waar inhet kader van het TOPsites project onderzoek isuitgevoerd naar de snelheid van erosie. Doel wasom te proberen vast te stellen hoe snel op dezelocatie erosie plaatsvindt. Bijkomende doelenwaren (1) om te testen welke methodes hetmeest geschikt zijn in een dergelijke context omerosiesnelheden te meten en (2) om te onderzoekenin hoeverre erosie schade toebrengt aande archeologische vindplaats.Grote Houw – een terrein van zeer hoge archeologischewaarde – bevat een deel van eencomplexe dubbelwierde. De verschillendemethodes die werden getest voor het meten vande erosiesnelheden gaven variabele resultaten:• Een vergelijking van de maaiveldhoogtesvolgens AHN1, AHN2 en een nieuwe groundbasedLIDAR opname leverde geen duidelijkbeeld op.• Met booronderzoek zijn aanwijzingen voorerosie gevonden in de vorm van variaties indiktes van de bouwvoor.• Een intensieve veldkartering leverde eenduidelijk beeld van de vondspreiding in relatietot de ligging van de wierde. Er waren echtergeen eenduidige aanwijzingen voor het recentopploegen van vondstmateriaal.• Vijf profielputten werden gegraven om debodemopbouw te bestuderen – met aandachtvoor de dikte van de bouwvoor en het evt.aanwezig zijn van colluvium.• OSL analyses (uit de profielputten) blekenvooral geschikt om erosie- en sedimentatieprocessenop langere tijdschalen teonderzoek. Daarbij was de spreiding aandateringen binnen één monster van groterbelang dan een absolute datering. Demetingen gaven een duidelijk beeld van deontstaansgeschiedenis van de wierde. Erosieof colluviumvorming was niet duidelijk aan tetonen.• Met metingen van de gehaltes aan 137Cs enplutonium in het profiel bleek het welmogelijk om schattingen van erosiesnelhedente maken over de periode van ca. 1960(detonatie van waterstofbommen in deatmosfeer) tot nu. Schatting is dat gedurendedeze 50 jaar maximaal 2 mm/jaar erosie isopgetreden.• De resultaten van 137Cs oppervlaktemetingenwaren op deze locatie niet geschikt om erosievast te stellen.

Nivellering en erosie zijn een algemeen bekendprobleem voor geaccidenteerde terreinenwaarop akkerbouw plaatsvindt. Grond zondervegetatie is gevoelig voor erosie, terwijl ploegenzorgt voor vervlakking en nivellering van reliëfverschillen.Verschillende tests zijn gedaan, metname in het buitenland, om de snelheid vandeze nivellering en erosie te karakteriseren.De resultaten zijn echter niet eenduidig, medeomdat verschillende tijdschalen wordengebruikt.Om beter grip te krijgen op de snelheid vanerosie en nivellering op archeologische vindplaatsenals gevolg van akkerbouw zijn vijflocaties uitgezocht. Met opzet is gekozen voorlocaties waarvan de verwachting is dat erosie/nivellering sterk is, zodat ze kunnen wordengezien als worst-case scenario. Binnen die groepis gekozen voor vindplaatsen waar eerderrelevante gegevens zijn verzameld overdegradatie en conservering. Twee (Beek-Kelmond en Meerssen – Onderste Herkenberg)liggen in het Limburgse lössgebied; drie andere(Schouwen, Grote Houw en Tjessens) zijnterpen/wierden. Op deze locaties wordenverschillende technieken ingezet om erosie ennivellering door de tijd in kaart te brengen.Uit het onderzoek op de vroegneolitische(Lineaire Bandkeramiek) vindplaats Kelmond-Beekerveld blijkt dat er aanwijzingen zijn voorvan significante erosie, met name op het steilstedeel van de helling. Hoewel het meestecolluvium op zijn laatst gevormd is tijdens delate middeleeuwen, zijn er duidelijke aanwijzingendat erosie actief was in de afgelopendecennia, en op dit moment ook nog plaatsvindt.De snelheid waarop de erosie plaatsvindt isaanzienlijk; in de afgelopen 50 jaar is enkeledecimeters aan grond verdwenen van de site,met name rond de hellingknik. De ouderedatering van het colluvium en de aanwezigheidvan een grote concentratie sporen op het steilstedeel van de helling zijn aanwijzingen dat dezeerosie komt na een langere periode van landschappelijkestabiliteit.De vergelijking van de maaiveldhoogtes uitverschillende jaren en de variaties daarin (metname de vergelijking tussen de twee generatiesvan het Actueel Hoogtebestand Nederland)duiden op erosie, maar deze resultaten op zichzijn niet overtuigend. De combinatie van 137Cs en239+240Pu metingen enerzijds en OSL metingenanderzijds geven wel uitkomsten die geschiktzijn voor het identificeren en kwantificeren vanerosie en colluviatie.Veel van de hier geteste methoden bleken nietgeschikt om de erosiesnelheden te meten. In demeeste gevallen waren ze te onnauwkeurig(bijvoorbeeld 137Cs oppervlaktekartering), warende effecten te onduidelijk (AHN/LIDARverschillen) of waren er oncontroleerbarevariaties in de gehaltes van bepaalde tracers.De tracers 137Cs en 239+240Pu gaven als enige welwaardes waaraan recente erosie kon wordenafgelezen. De schatting van de snelheden isgebaseerd op een aantal aannames, waardoorde schattingen vooral als indicatie moetenworden gezien. Nader onderzoek naar hetgebruik van deze isotopencombinatie zou debetrouwbaarheid van de schatting kunnenverbeteren.OSL bleek vooral geschikt om erosie en depositieop tijdschalen van (tientallen) eeuwen tebepalen. Het is daarmee een goede ondersteunendetechniek – in combinatie met tracers – omde landschappelijke ontwikkeling en erosiegevoeligheidvan een vindplaats te onderzoeken.Voor toekomstig onderzoek, waarbij hetschatten van mate van erosie van belang is, ishet aan te raden om een combinatie van 137Cs en239+240Pu als tracers en OSL als ondersteuning enlandschapsontwikkeling toe te passen. Een extravoordeel van deze combinatie is dat ze ook eenindicatie kunnen geven van de mate van bioturbatieop een vindplaats en de timing ervan.Ten aanzien van het monument zelf kunnen eenaantal aanbevelingen worden gedaan. Uit hetonderzoek blijkt dat er sprake is van stevigeerosie op delen van het terrein. Omdat veel vande sporen direct onder de bouwvoor liggen, is devindplaats zeer kwetsbaar. Eenmaal dieperploegen dan de bouwvoor brengt schade eninformatieverlies met zich mee. Een gebruik vanhet monument als grasland verdient daarom devoorkeur.

Combining field reconstruction and landscape evolution modelling can be useful to investigate the relative role of different drivers on catchment response. The Geren Catchment (~45 km2) in western Turkey is suitable for such a study, as it has been influenced by uplift, climate change and lava damming. Four Middle Pleistocene lava flows (40Ar/39Ar- dated from 310 to 175 ka) filled and dammed the Gediz River at the Gediz–Geren confluence, resulting in base-level fluctuations of the otherwise uplift-driven incising river. Field reconstruction and luminescence dating suggest fluvial terraces in the Geren Catchment are capped by Middle Pleistocene aggradational fills. This showed that incision of the Geren trunk stream has been delayed until the end of MIS 5. Subsequently, the catchment has responded to base-level lowering since MIS 4 by 30 m of stepped net incision. Field reconstruction left us with uncertainty on the main drivers of terrace formation. Therefore, we used landscape evolution modelling to investigate catchment response to three scenarios of base-level change: (i) uplift with climate change (rainfall and vegetation based on arboreal pollen); (ii) uplift, climate change and short-lived damming events; (iii) uplift, climate and long-lived damming events. Outputs were evaluated for erosion–aggradation evolution in trunk streams at two different distances from the catchment outlet. Climate influences erosion–aggradation activity in the catchment, although internal feedbacks influence timing and magnitude. Furthermore, lava damming events partly control if and where these climate-driven aggradations occur. Damming thus leaves a legacy on current landscape evolution. Catchment response to long-duration damming events corresponds best with field reconstruction and dating. The combination of climate and base level explains a significant part of the landscape evolution history of the Geren Catchment. By combining model results with fieldwork, additional conclusions on landscape evolution could be drawn.

Landscapes respond in complex ways to external drivers such as base level change due to damming events. In this study, landscape evolution modelling was used to understand and analyse long-term catchment response to lava damming events. PalaeoDEM reconstruction of a small Turkish catchment (45km(2)) that endured multiple lava damming events in the past 300ka, was used to derive long-term net erosion rates. These erosion rates were used for parameter calibration and led to a best fit parameter set. This optimal parameter set was used to compare net erosion landscape time series of four scenarios: (i) no uplift and no damming events; (ii) no uplift and three damming events; (iii) uplift and no damming events; and (iv) uplift and three damming events. Spatial evolution of net erosion and sediment storage of scenario (iii) and (iv) were compared. Simulation results demonstrate net erosion differences after 250 000years between scenarios with and without dams. Initially, trunk gullies show less net erosion in the scenario with damming events compared with the scenario without damming events. This effect of dampened erosion migrates upstream to smaller gullies and local slopes. Finally, an intrinsic incision pulse in the dam scenario results in a higher net erosion of trunk gullies while decoupled local slopes are still responding to the pre-incision landscape conditions. Sediment storage differences also occur on a 100ka scale. These differences behaved in a complex manner owing to different timings of the migration of erosion and sediment waves along the gullies for each scenario. Although the specific spatial and temporal sequence of erosion and deposition events is sensitive to local parameters, this model study shows the manner in which past short-lived events like lava dams have long-lasting effects on catchment evolution. Copyright (c) 2014 John Wiley & Sons, Ltd.

Natural damming of upland river systems, such as landslide or lava damming, occurs worldwide. Many dams fail shortly after their creation, while other dams are long-lived and therefore have a long-term impact on fluvial and landscape evolution. This long-term impact is still poorly understood and landscape evolution modelling (LEM) can increase our understanding of different aspects of this response. Our objective was to simulate fluvial response to damming, by monitoring sediment redistribution and river profile evolution for a range of geomorphic settings.We used LEM LAPSUS, which calculates runoff erosion and deposition and can deal with non-spurious sinks, such as dam-impounded areas. Because fluvial dynamics under detachment-limited and transport-limited conditions are different, we mimicked these conditions using low and high erodibility settings, respectively. To compare the relative impact of different dam types, we evaluated five scenarios for each landscape condition: one scenario without a dam and four scenarios with dams of increasing erodibility. Results showed that dam-related sediment storage persisted at least until 15 000 years for all dam scenarios. Incision and knickpoint retreat occurred faster in the detachment-limited landscape than in the transport-limited landscape. Furthermore, in the transport-limited landscape, knickpoint persistence decreased with increasing dam erodibility. Stream capture occurred only in the transport-limited landscape due to a persisting floodplain behind the dam and headward erosion of adjacent channels. Changes in sediment yield variation due to stream captures did occur but cannot be distinguished from other changes in variation of sediment yield. Comparison of the model results with field examples indicates that the model reproduces several key phenomena of damming response in both transport-limited and detachment-limited landscapes. We conclude that a damming event which occurred 15 000 years ago can influence present-day sediment yield, profile evolution and stream patterns.

Sediment flux dynamics in fluvial systems have often been related to changes in external drivers of topography, climate or land cover. It is well known that these dynamics are non-linear. Recently, model simulations of fluvial activity and landscape evolution have suggested that self-organization in landscapes can also cause internal complexity in the sedimentary record. In this contribution one particular case of self-organization is explored in the Sabinal field study area, Spain, where several dynamic zones of sedimentation and incision are observed along the current river bed. Whether these zones can be caused by internal complexity was tested with landscape evolution model (LEM) LAPSUS (Landscape Process Modelling at Multi-dimensions and Scales). During various 500¿year simulations, zones of sedimentation appear to move upstream and downstream in eroding river channels (‘waves’). These waves are visualized and characterized for a range of model settings under constant external forcing, and the self-organizing process behind their occurrence is analysed. Results indicate that this process is not necessarily related to simplifications in the model and is more generic than the process of bed-armouring that has recently been recognized as a cause for complexity in LEM simulations. We conclude that autogenic sediment waves are the result of the spatial propagation in time of feedbacks in local transport limited (deposition) and detachment limited (erosion) conditions

This chapter reviews quantitative modeling of landscape evolution – which means that not just model studies but also modeling concepts are discussed. Quantitative modeling is contrasted with conceptual or physical modeling, and four categories of model studies are presented. Procedural studies focus on model experimentation. Descriptive studies use models to learn about landscapes in general. Postdictive and predictive try to correctly simulate the evolution of real landscapes, respectively in the past (with calibration) or in the future (with calibrated models). The geomorphic process is a central concept in landscape evolution modeling. We discuss problems with the field-based definition of these processes from a modelling perspective. After the classification of 117 landscape evolution studies in these categories, we find that descriptive studies are most common, and predictive studies are least common. In the remainder of the chapter, we list and review the 117 studies. In procedural studies, attention has been focussed at production methods for digital landscapes, spatial resolution and the role of sinks and depressions. Descriptive studies focussed mainly on surface–tectonic interactions, sensitivity to external forcing, and the definition of crucial field observations from model results. Postdictive and predictive studies operate mainly in time-forward mode and are sometimes validated (postdictive studies of soil redistribution over centennial to millennial timescales). Finally, we look ahead to the future of landscape evolution modeling, arguing for a larger role for complexity research, predictive studies and uncertainty analysis, process definition and feedbacks to and from other fields (including ecology).

In Brazil, agriculture expansion is taking place primarily in the Cerrado ecosystems. With the aim of supporting policy development and protecting the natural environment at relevant hotspots, a scenario study was conducted that concerned not only land-use change, but also the resulting effects on erosion and deposition. This coupled approach helped to evaluate potential landscape impacts of the land-use scenarios. In the study area, the Balsas sub-basin in Maranhão State, a model chain was used to model plausible future soybean expansion locations (CLUE-S model) and resulting sediment mobilization patterns (LAPSUS model) for a business-as-usual scenario. In the scenario, more erosion occurred in areas where the conversion of natural vegetation into soybean cultivation is likely to take place, but the generated sediments tended to accumulate mainly within the conversion areas, thus limiting the offsite effects of the increased erosion. These results indicated that when agricultural expansion is kept away from rivers, Cerrado conversion will have only a limited impact on the sediment loads of local rivers. Where land-use changes are most concentrated are coincident with areas where more new sediments are generated (higher erosion) and where more sediments are re-deposited.

The origin of the lower Miño River terraces in the NW Iberian Peninsula has been a topic of debate since the 1940s. Various hypotheses about their main controlling factors have been put forward, but general consensus is still lacking. Field studies of terrace distribution and the weathering of quartzite pebbles in the terrace deposits demonstrated that terrace longitudinal correlation is not parallel to the current river bed. In addition, the longitudinal profile model FLUVER2 was used to simulate the profile evolution of the Miño River over the past 450 ka. A reconstructed longitudinal profile and an offshore climate record were used as inputs. Several scenarios with variable uplift rates were investigated and evaluated against properties of four selected reaches along the river for a match with the number of terraces, their relative altitude, timing, and sediment thickness. An uplift scenario with a net constant vertical uplift rate of 0.08 m ka 1 yielded the best results. The best fit scenarios indicate that base level changes from glacioeustatic changes in combination with tectonic uplift are the main driving forces of the observed terrace formation and valley incision. Contrary to most NW European fluvial systems, the timing of upstream-controlled sediment supply has a less dominant effect on terrace formation. This can be explained by the close proximity to the narrow passive Atlantic margin.

This chapter discusses and illustrates how changes in slope angle can cause mass movement. Several processes can cause removal of lateral or underlying support of a slope, and most of the time multiple processes are acting together on a landscape. Slow and sudden processes causing changes in slope angle are differentiated, and several examples and illustrations of each are given. In addition, this chapter reviews current literature on landscape evolution modeling in which researchers try to incorporate these geomorphological processes in the analysis and simulation of current and future landscapes.

A new fluvial terrace map with a tectonic framework for the northwest Iberian lower Miño River is presented. It is the first integrated map to cover the entire lower, 67-km reach of the Miño River, and to cover both the Spanish and Portuguese side of the river. The map is presented at a scale of 1:200,000, although its features were mapped at a scale of 1:5000. Various map layers can be viewed, such as a digital elevation model (DEM), fluvial sediment thickness layers, a palaeoflow direction layer, a lineament and fault layer, and two terrace and tectonic basin layers, showing up to 10 fluvial terraces and a floodplain level. Interpretation of the map shows that next to regional tectonic uplift and glacioeustacy, local basin subsidence and small-scale block movement are very important for the fluvial network, localised fluvial terrace formation, and preservation. © 2013 Copyright Willem Viveen.

This chapter reviews quantitative modeling of landscape evolution – which means that not just model studies but also modeling concepts are discussed. Quantitative modeling is contrasted with conceptual or physical modeling, and four categories of model studies are presented. Procedural studies focus on model experimentation. Descriptive studies use models to learn about landscapes in general. Postdictive and predictive try to correctly simulate the evolution of real landscapes, respectively in the past (with calibration) or in the future (with calibrated models). The geomorphic process is a central concept in landscape evolution modeling. We discuss problems with the field-based definition of these processes from a modelling perspective. After the classification of 117 landscape evolution studies in these categories, we find that descriptive studies are most common, and predictive studies are least common. In the remainder of the chapter, we list and review the 117 studies. In procedural studies, attention has been focussed at production methods for digital landscapes, spatial resolution and the role of sinks and depressions. Descriptive studies focussed mainly on surface–tectonic interactions, sensitivity to external forcing, and the definition of crucial field observations from model results. Postdictive and predictive studies operate mainly in time-forward mode and are sometimes validated (postdictive studies of soil redistribution over centennial to millennial timescales). Finally, we look ahead to the future of landscape evolution modeling, arguing for a larger role for complexity research, predictive studies and uncertainty analysis, process definition and feedbacks to and from other fields (including ecology).