Terrace System Research Articles

The impact of agriculture on tropical mountain soils in the western Peruvian Andes: a pedo-geoarchaeological study of terrace agricultural systems in the Laramate region (14.5° S)

Abstract. This integrated pedo-geoarchaeological study focuses on three abandoned pre-Hispanic terrace agricultural systems near Laramate in the southern Andes of Peru (14.5° S), aiming to unravel the pedological and land-use history of the region, which served as a significant agricultural hub during pre-Hispanic times. The key objectives of the investigation involved contextualizing the former agricultural management system within its geomorphological and palaeoecological framework and assessing the impact of agricultural practices on soil development and quality by comparing non-irrigated agricultural terrace soils with their undisturbed palaeo-pedological counterparts. The Laramate terrace complex, with its diverse terrace systems and varied geomorphological and geological settings, provided an ideal setting for the investigation. This comprehensive examination integrated a range of methodologies, including field surveys, digital mapping, and geomorphological analysis based on GIS and remote sensing applications, soil analysis (e.g. grain size, bulk chemistry, nutrient budget), plant microfossils (phytoliths and starch), and radiocarbon dating. In the Laramate region, the geomorphological setting of terrace agricultural systems promotes their optimal functioning. The terraces are often located in sun-sheltered areas with western exposure on middle and lower slopes or valley bottoms, which mitigate intense solar radiation, reduce evapotranspiration, increase soil moisture, and minimize erosion. The study identifies three soil groups in the Laramate region: Phaeozems, Andosols, and Anthrosols. Unique characteristics of Phaeozems challenge typical descriptions, influenced by factors such as climatic seasonality, vegetation, fauna, lithology, and aeolian inputs. The terrace soils in the Laramate region are classified as Terric Anthrosols, showing no significant degradation even after long-term use. Their balanced acidity and nutrient levels support Andean crop cultivation. Traditional non-mechanized tools, such as the chaquitaclla and rucana, likely minimized soil disruption. The terrace tillage horizons have high organic matter, indicating intentional organic manuring. Phytolith concentrations suggest intensive agricultural activity, particularly maize cultivation, with varying patterns suggesting changes in cultivation, fertilization, or mulching practices over time. Starch grain identification aligns with phytolith analyses, reinforcing maize's significance in the region. Although the use of animal-origin fertilizers requires further investigation, there is no evidence of nutrient maintenance through seasonal burning. Irrigation was minimal, and the abandonment of the pre-Hispanic cultivation system was unlikely due to soil exhaustion or terrace instability. Overall, the pre-Hispanic history of terrace agriculture in the Laramate region extends over four development phases, reflecting dynamic interactions between environmental, cultural, and agricultural factors. The initial phase, from the Formative Paracas period to the Early Nasca period (800 BCE–200 CE), witnessed the establishment of agricultural terraces with simple terrace architecture, while the Middle Horizon (600–1000 CE) saw systematic areal expansion influenced by the Wari culture. Adaptations to drier conditions included terrace agriculture on volcanic soils. The Late Intermediate period (1000–1450 CE) witnessed hydrological variability and further terrace expansion to lower altitudes and less agriculturally suitable locations. The final phase, marked by the onset of the Hispanic colonial period in 1535 CE, saw the gradual abandonment of terrace agricultural systems due to demographic shifts and reorganization of production systems. Despite this, the historical trajectory underscores the adaptability and resilience of pre-Hispanic communities in the Laramate region, showcasing innovative terrace agriculture as a means of coping with changing environmental conditions across diverse landscape units.

Agricultural terraces in Puebla, Mexico: An ethnopedological approach

Terrace systems have been instrumental in the evolution of agriculture across various cultural contexts. This technology offers several benefits, including soil and water conservation, improved soil fertility, enhanced agricultural management, and increased crop yields. Several studies have been conducted on agricultural terraces in Mesoamerica. Nevertheless, there has been a lack of research on anthropogenic soils and ethnopedological studies in Mexico. This study aimed to ascertain the local soil knowledge and describe the ancestral terrace systems within a popoloca community in southern Puebla, Mexico. An ethnopedological survey was conducted on a 10,366 ha area to determine the land types and terrace systems present. Surface terraced soil samples were collected, and nine soil profiles within runoff terraces were described. The objectives were as follows: 1) to characterize and describe terrace systems in Santiago Acatepec, 2) to understand the indigenous land classification system and 3) to study the relation and impact of terraces systems on soil formation and WRB classification. The results indicate two types of terraces (hillside and runoff terraces), covering 2578 ha of land. Farmers recognize eight distinct land classes, with unique characteristics and agricultural uses. The land classes encompass both anthropogenic and natural soils. These land classes are classified as Terric Anthrosols, Eutric Regosols, Eutric Leptosols, and Pellic Vertisols. These results show farmers' detailed knowledge about their soils and the advantages and limitations of terraces. The modern and ancient terraces were classified according to seven diverse types of embankments or walls. The traditional embankment, designated as “cuaxustles,” is associated with runoff terraces and is known to have a lifespan exceeding one hundred years. Following the construction of a terrace, the land in question can be cultivated for agricultural purposes after a period of two years. The traditional knowledge of the soil has enabled the farmers of Acatepec to establish new agricultural areas, select crops that are well-suited to the soil conditions and climate of the region, and implement long-term modifications to the landscape. The findings indicate that it is feasible to implement environmental modifications that prioritize soil conservation and enhancement on a significant scale while also considering economic factors and the time frame involved.

A Transdisciplinary Analysis of the 2009 Catastrophe in Giampilieri Superiore by Land Use Evolution Over Time

AbstractOn October 1 2009 a deluge hit the Peloritani Mountains, in NE Sicily, Italy, where the rainfall data recorded 225 mm in 9 h. Giampilieri Superiore was the most affected townlet in terms of infrastructural damages and human losses (37 dead, 37 wounded, and more than 1000 evacuees). The debris flows, triggered by flash floods wreaked havoc of the urban structure. More than 200 mln € was granted to protection works for conveying water and debris flows to bypass the town. The disaster was numerically simulated by SCIDDICA (Digital Twin) with excellent approximation, and the effects of the safety installation were tested as well, proving to offer sufficient protection for the village. The Peloritani area overlooking the Ionian See flourished during the Saracen domination, whose legacy of systems of terraces, cisterns and wells guaranteed the finest water management in steep terrains, allowing a safe emplacement of watermills, around which Giampilieri and other villages developed. This hydraulic legacy has been undermined during the last decades due to lack of appropriate maintenance because of the progressive loss of the Saracen culture. It is unconceivable that subsidies on the scale granted to Giampilieri are sustainable when facing innumerable future climatic disasters. A cheaper and more viable solution is to be found, e.g., the settlement of immigrants in the area, promoting the labor-social inclusion of those persons who already possess such a Saracen culture or are willing to acquire it from the last local depositaries, according to a retro-innovation perspective and methodology.

Long-term evolution of soil quality in citrus orchard terrace system: A whole life cycle perspective

Terracing is widely recognized as an effective strategy for mitigating soil erosion and preserving soil quality. This study aimed to evaluate the variations in soil aggregate C, N, and P composition, as well as the soil quality index (SQI), in subtropical citrus orchards of different plantation ages (PA) and across various terrace positions (TP). Surface soil samples (0–20 cm) were collected from four TP categories: terrace wall (TW), slub ditch (SD), under grove (UG), and between grove (BG), across varying PA (5, 15, 25, 35, and 45 years). The results showed the C, N, and P concentrations in most soil aggregates, along with the SQI of the slub ditch and under grove, increased significantly with plantation age. Compared to the 5-year-old plantations, the SQI of the slub ditch and under grove increased by 84 % and 66 % at 45 years, respectively. The aggregate stability and SQI of BG generally trended upwards but declined at 25 and 35 years. By 45 years, the SQI of the terrace wall was significantly lower than that of other positions, being 58 %, 61 %, and 39 % lower compared to the slub ditch, under grove, and between grove, respectively. Additionally, the C/P and N/P ratios of the terrace wall were higher than those of other positions, indicating phosphorus limitation in TW. Path analysis revealed plantation ages had greater effects on SQI. Aggregate stability and soil properties showed significant positive impacts on SQI. Overall, as plantation age increased, the differences in SQI among the slub ditch, under grove, and between grove decreased, while the terrace wall exhibited the weakest erosion resistance. Therefore, efforts should be made to restore the ecological function of the terrace wall, such as by colonizing it with moss. Additionally, reasonable tillage plans, including appropriate fertilization, should be formulated to enhance orchard soil quality.

Agricultural Terracing and Land Tenure in Late Medieval Southern Levant: The Case of Nahal Ein Karim, Jerusalem

ABSTRACT Recent research into agricultural terrace systems across the Jerusalem Highlands, has revealed a significant pattern: the majority of terraces were constructed within the past 700 years, during the Mamluk and Ottoman periods. The motivation for building terrace systems, a labour-intensive endeavour requiring significant long-term investment, appears to be associated with land management policies. This study set out to test this hypothesis, by focusing on the terrace system at Nahal (wadi) Ein-Karim, Jerusalem, and the adjacent site of Khirbet Beit-Mazmil. The study employed portable OSL (POSL) profiling of sediments and OSL dating of the terraces and other related features, alongside archival document analysis. A key element of this study was the examining and dating of plot fences, which serve as tangible representation of shifts in land tenure. The utilisation of POSL profiling facilitated comprehension of their sedimentation dynamics and aided in identifying the optimal sampling approach for OSL dating. The findings highlight a direct link between land endowment practices and terrace construction, particularly evident from the fourteenth century CE onwards. This interdisciplinary approach contributes to our understanding of agricultural terracing dynamics, shedding light on the intricate interplay between land tenure systems, socio-economic factors, and landscape modification practices in the Late-Medieval Southern-Levant.

Extended-range luminescence and ESR dating of Iberian fluvial terraces (Duero and Guadiana basins) associated with the Lower Palaeolithic sites of La Maya I, II, III, Burganes and Albalá (west-central Spain)

The major river basins of the Iberian Peninsula that drain towards the Atlantic coast contain extensive Lower Palaeolithic (Acheulean) records associated with well-preserved fluvial terrace sequences. These open-air archaeological records are often difficult to constrain chronologically due to a lack of suitable material for dating (e.g., faunal remains) or because their Middle Pleistocene antiquity precludes the use of otherwise routinely applicable geochronometric techniques such as conventional optically stimulated luminescence (OSL) dating. As a result, many important Iberian Acheulean sites lack precise and accurate chronologies, and their existing temporal frameworks are based solely on morphostratigraphic correlations with regional fluvial terrace systems. Here we present the first application of extended-range luminescence dating – namely multi-grain post-infrared infrared stimulated luminescence (pIR-IRSL) dating of K-feldspars and single-grain thermally transferred-OSL (TT-OSL) dating of quartz – to a series of terrace sequences in the Duero basin (central sector) and Guadiana basin, as well as associated Lower Palaeolithic sites of La Maya I, II and III along the Tormes River, Burganes (and related sites) along the Tera River, and Albalá along the Guadiana River. Additionally, we present results of a parallel electron spin resonance (ESR) quartz dating study of the Tormes River terrace (Duero basin), which has been undertaken independently on the same samples to enable stratigraphically paired dating comparisons. Our study indicates that sedimentary quartz from this sector of the Duero basin produces very weak TT-OSL signals, variable Al signal repeatability and below-average Ti signal fitting uncertainties, though it is still possible to determine consistent comparative ages using the measurements protocols employed here. For samples where both pIR-IRSL and TT-OSL signals were measured, the paired luminescence dating ages are in agreement at 1σ. Agreement between the quartz ESR and TT-OSL ages is also observed for one sample from the Tormes River. However, the ESR signals (both Al and Ti) of a second sample showed insufficient bleaching and age overestimation in comparison to the paired TT-OSL dataset. Comparison of our latest dating results with published chronological datasets point to some fluvial terraces of the Duero basin potentially having diachronous formation histories. Despite this, our combined chronological results show that the terrace systems are chronologically ordered and suggest that, regionally, the +8 to +34 m terraces likely post-date marine isotope stage (MIS) 10, whilst the +50 m terraces formed prior to, or during, MIS 10. The related Acheulean sites that contain lithic material in stratigraphic position are dated to MIS 9–7 (193–314 ka at 2σ age range), and temporally overlap with the early Middle Palaeolithic records in the Duero basin, also dated here to MIS 8–7 (or 159–259 ka at 2σ). Our results are consistent with previous observations regarding the chronological overlap of these two technologies in the region, and support the possibility of a non-linear pattern of replacement for the Acheulean in the Iberian Peninsula during the Lower to Middle Palaeolithic transition.

Middle Loire Valley settlement: First chronology using ESR on quartz grains

Over the past two decades, stepped-terrace systems within the Loire River basin's tributaries have undergone comprehensive multidisciplinary studies, encompassing Quaternary geology, prehistory and geochronology. Surprisingly, the geochronological exploration of the Loire River itself, the longest river in France, and its fossil stepped terraces system has been relatively limited, especially in the middle section near Orléans. However, for about fifty years, this region has been pivotal in providing evidence of the historical confluence of two ancient rivers, shaping the current Loire Valley. Researchers have suggested the existence of a Plio-Pleistocene Loire paleo-river, flowing northward from the Massif Central to the Seine valley and eventually reaching the English Channel. Subsequently, this Loire River would have underwent a reorientation of its flow westward, from the Blois area to the Atlantic Ocean, after being disconnected from its previous course.The absence of alluvial deposits in the area between the current Loire valley and the Seine valley, attributed to substantial erosion, prevents direct exploration of evidence related to the south-north paleo-river. To address this challenge, the hypothesis suggests that the preserved alluvial terraces in the intermediate sector were established post-capture, offering an opportunity to determine when this significant geological event occurred. Through the application of Electron Spin Resonance (ESR) quartz dating, a chronological model for the Middle Loire has been then constructed. This model identifies five distinct phases in the evolution of the Middle Loire system, spanning from 800 ka to the present day. These phases indicate a gradual capture process, initiating between 900 and 800 ka, resulting in alterations to fluvial dynamics and ultimately leading to the establishment of the current course approximately 250 ka.

Late Middle Pleistocene (MIS 10–6) glacial–interglacial records from loess–palaeosol and fluvial sequences from northern France: a cyclostratigraphic approach

This contribution summarizes the most informative loess–palaeosol sequences (LPS) and fluvial terrace records from the late Middle Pleistocene (LMP) of northern France demonstrating the reliability of the cyclostratigraphic approach for the interpretation of pedosedimentary sequences controlled by major glacial–interglacial climatic cycles. In this area, continental mollusc assemblages from interglacial fluvial silts and calcareous tufas are particularly rich and diverse and marker species define the malacological signatures of each interglacial optimum for Marine Isotope Stages (MIS) 11, 9 and 5e. This approach shows that the forest was less developed during MIS 7, suggesting that climatic conditions were either drier and/or cooler than during other Pleistocene interglacials. In the Somme basin, the terrace system shows that two alluvial formations were deposited between early MIS 8 and late MIS 7. In some LPS, the occurrence of two pedosedimentary sub‐cycles (IIa and IIb), separated by a relatively long (~12 ka) and cold period, corresponding to an ‘aborted glacial’ (MIS 7d), underlines the complex pattern of this unusual ‘interglacial’. Overall, during the LMP, each soil complex corresponding to interglacial and early‐glacial periods from MIS 11 to MIS 5 is broadly made up of the same soil facies but exhibits a specific succession pattern or signature. Throughout the area, LPS show a huge change in both the deposition rates and the geographical extent of typical calcareous loess at the beginning of MIS 6. This so‐called ‘Loess Revolution’ probably reflects a change in the palaeogeography of the southern North Sea and eastern Channel source areas at times marked by the coalescence of the British and Scandinavian ice sheets. MIS 6 is also characterized by the oldest evidence of permafrost development in the area. In addition, this work allows the age of the Lower/Middle Palaeolithic boundary to be confirmed, with the oldest occurrence of Levallois technology being around 300 ka.

Morphostructural evolution of the Labe and Jizera rivers confluence area (the Bohemian massif, Czechia)

This article investigates the morphostructural evolution of the Labe and Jizera rivers confluence area in the Bohemian Massif of Czechia. The main stages of morphostructural evolution are identified and related landform patterns are described. The lithological and tectonic character of this contact area between the Barrandian and the Bohemian Cretaceous Basin has been gradually evolving since the Early Palaeozoic. Tectonic subsidence of the northeastern part of the Bohemian Massif and the Cretaceous transgression of the sea caused extensive marine sedimentation, which covered the pre-Cenomanian relief. The uplift of the Bohemian Massif during the Santonian initiated a widespread erosion and denudation in the Tertiary. The Labe River valley constitutes a remarkable boundary between the morphostructural plateaus in the south and the system of river accumulation terraces of the Labe and Jizera in the north. The originally extensive and currently considerably eroded III. river terrace of the Labe was formed in the Elsterian glacial period (Cromerian complex c). The conspicuous Jizera alluvial fan developed during the aggradation phase of the VII. river terrace in the Upper Pleistocene. Subsidence along the NW-SE-trending Labe Fault zone, deciphered from the vertical throw of the VII. terrace rock bases of Labe as well as related paleochannels of its local tributaries, which caused the current asymmetry of the Labe valley, reached up to 14 meters prior to the Holocene. The different rock resistance to weathering, arrangement of fault structures and neotectonic movements that took place even during the late Quaternary significantly influenced the intensity of varied climate-morphogenetic processes.

Last interglacial in western Europe: 20 years of multidisciplinary research on the Eemian (MIS 5e) calcareous tufa sequence at Caours (Somme basin, France) – a review

The calcareous tufa sequence and associated Palaeolithic site of Caours were discovered in 2002 during a test‐pit campaign aimed at identifying last interglacial (MIS 5e) archives in the fluvial terrace system of the Somme basin, northern France. The presence of an outstanding stratigraphical succession with four in situ Palaeolithic layers within the tufa sequence has motivated archaeological excavations of the site since 2005. The first malacological studies and U‐series ages quickly showed that the sequence was mainly deposited during the Eemian interglacial (MIS 5e). After 20 years of investigations, we propose here a summary of this multidisciplinary research project including stratigraphy, sedimentology, geochronology, geochemistry, malacology, mammals, palaeovegetation and archaeology. By combining 25 dates obtained by U‐series, ESR/U‐series, TL and OSL methods, the Caours calcareous tufa sequence is securely dated to the Eemian (123.1±2.8 ka). Based on the summary of the whole information, we propose a robust and detailed reconstruction of the modification of the valley environments between the Late Saalian and the Early Weichselian. At the scale of northwestern Europe, Caours provides a reference terrestrial molluscs record for the Eemian interglacial, including the climatic optimum, that is also described in the same layers by δ18O and δ13C analyses on calcite and by mammal remains. Moreover, the 300‐m‐long transect crossing the fluvial terrace covered by the tufa sequence and the bottom valley formation, combined with the chronology established from U‐series and OSL ages, shows that the incision of the present‐day valley, leading to the setting of the Very Low Terrace, was achieved during the first stages of the Early Weichselian (MIS 5d–5c). From an archaeological point of view, the configuration of the Caours site is unique at the scale of western Europe and demonstrates the adaptation of Neandertals to a forested environment and to fully temperate conditions during the Eemian.

Investigating the Neolithic Presence in South-Central Oman: The DUQ-25A Rock Shelter

Over the past decade, extensive surveys have been carried out in the wider area surrounding the city of Duqm (south-central Oman). During fieldwork in 2023, research on the Neolithic encampment in the Wādī Ṣayy area was conducted. Numerous locations surrounding this large wadi have yielded evidence of Neolithic occupation. The proximity to chert outcrops and the presence of elevated fluvial terrace systems overlooking the wadi floodplains likely played a pivotal role in attracting human habitation during that period. Among these sites, DUQ-25A stands out for its exceptional preservation and the abundance of flint scatters. The excavation at the site aimed to achieve multiple objectives: validating the site’s chronology, expanding our understanding of its spatial extent and occupational sequence and filling the gaps in our knowledge about Neolithic societies in south-central Oman. Our research aims to provide new perspectives for the study of the Early and Middle Holocene in Al-Wusṭā.

Evolution of the Júcar-Cabriel fluvial system on the Mediterranean watershed of the Iberian Peninsula (Valencia, eastern Spain)

This study presents the characterization and chronology of the Quaternary terrace sequence developed in the confluence zone of the Júcar and Cabriel river valleys. The study area covers a radius of 10 km from the confluence of the two valleys near the locality of Cofrentes (Valencia). It is located in the northern zone of the Ayora-Cofrentes Graben in the northeastern sector of the External Prebetic Zone adjacent to southern Iberian Chain. This N-S graben is an inherited tectonic feature with an axial salt wall subject to different periods of fluvial dissection and refilling since at least the end of the Messinian Salinity Crisis (MSC). Regional isostatic uplift and local uplift and subsidence processes related to salt flow and dissolution during the Quaternary period, favored by fluvial entrenchment and terrace development. The terrace system and the previous pre-incision erosional and depositional surfaces are analyzed from a geomorphological point of view. The terrace system only develops within the soft Mio-Pliocene sedimentary fill of the graben, whilst upstream and downstream this zone the studied valleys develop important gorges (canyons) carved in the Cretaceous tablelands (Caroch Massif) and Mio-Pliocene deposits (Llanura Manchega). The geochronological control is established from 20 numerical ages obtained by different dating methods, such us Electron Spin Resonance (ESR), Optically Stimulated Luminescence (OSL) in detrital sequences and Th/U series in calcareous tufa deposits. Additionally, four K/Ar dates available for volcanic materials disrupting the upper and oldest terrace have been considered. A total of 14 terrace levels were identified between +130–135 m (T1) and +3–4 m (T14) of relative height above the river thalwegs. The T1 has an approximate age of c. 1.6–2.0 M.a. as indicate the age of the volcanic materials from the Agras Volcano intruded in the terrace, marking the onset of Quaternary fluvial dissection in the zone. The obtained geochronological data indicate that the Lower-Middle Pleistocene boundary is slightly above T6 (+60–65 m), which has an ESR age of 577 ± 43 ka. This terrace also documents the onset of the most important period of rise of the salt within the graben interfering drainage development. The geochronological data indicate the occurrence of a second eruptive event during the second half of the Middle Pleistocene related to the terraces T7 (+50 m) and T8 (+35–40 m), updating the volcanic activity in the zone. The beginning of the Upper Pleistocene is recorded by the top sequences of the T9 terrace (+25–30 m) where numerous OSL and Th/U data have been obtained with ages between ca. 105 and 81 ka (MIS 5). However, these young terraces (T8 to T13) are thickened (8–10 m) recording Middle Pleistocene sediments in their basal sequences with ages between ca. 193 and 137 ka (MIS 6). The study provides important data on valley evolution under the interference of volcanic activity, salt –related deformation (diapirism, solution subsidence) and fluvial incision fostered by the rise of the axial diapir (salt wall) protruding the graben since at least the Brunhes-Matuyama boundary. The analyzed fluvial evolution documents interesting cases of river capture, drainage antecedence and tectonic adaptation of the drainage throughout the Quaternary Period. The paper also poses interesting geochronological data on the long-term Quaternary evolution of Mediterranean valleys in the Iberian Peninsula, poorly explored to the date.

Центр створення та розвитку стартапів Національного університету «Чернігівська політехніка»: архітектурна реновація будівлі колишнього кінотеатру «Перемога» в Чернігові

Based on modern humanistic principles of architectural and urban design and system analysis of three-dimensional solutions of the former «Peremoha» cinema in Chernihiv, the results of the study of architectural and conceptual images are presented and a project for the architectural renovation of the new building of the Center for the Creation and Development of Startups of Chernihiv Polytechnic National University is proposed. The project envisages the spatial transformation of space using a system of load-bearing wooden frame structures and innovative glass construction technologies. The designed superstructures, together with the system of terraces and balconies, will visually create a transparent space for the interior of the new building, accessible to sunlight and convenient for educational, scientific and artistic activities of students, teachers and active residents of the city.

Franco Minissi e il progetto dell’antiquarium di Himera a Termini Imerese (1963-1984): memoria storica e coscienza moderna

The contribution describes the genesis of the project to enhance the archaeological area of ancient Himera and the construction of the antiquarium which begun in the early 1960s to a design by Franco Minissi. The antiquarium, built along the slope of the mountain, is characterised by a system of sloping terraces that follow the natural progression of the terrain, blending built architecture and natural scenery without any pretence. At the same time, the system of sloping terraces defines the internal museographic itinerary built around a continuous and unified system of ramps, a true architectural promenade, which articulate the space and organise the exhibition: “Double-height rooms and internal overlooks vary and enliven the visit itinerary; the void itself becomes an ‘exhibition machine’; its flow seeks to capture the attention of the visitors and draw them in. Diversified sequences, through a shrewd architectural as well as museographic design, where the exhibits are made to interact with the environment that contains them”.

New insight on the structural architecture of northern Tunisia with a multidisciplinary approach: Association of Miocene piggy-back basin and active Plio-quaternary out-of-sequence thrusts

In order to better understand the intricate structural architecture of northern Tunisia, we use a multidisciplinary approach that includes field observations, geomorphic, sedimentological, and gravity data across this area. We offer a model of progressive thrusting in which four deformation phases occurred in the context of plate convergence (i) Uplift of the Jebel Ichkeul Triassic succession via a NE-trending thrust fault during the Eocene; (ii) Advance of Numidian thrust sheets during the late Oligocene-Middle Miocene, causing the formation of the Lake Ichkeul/Jalta as being piggy-back basin; (iii) Initial out-of-sequence thrusting during the Late Miocene, resulting in the formation of the Sejnane and El Mejel basins with syntectonic Pliocene infill; and (iv) Subsequent out-of-sequence thrusting during the Early Pleistocene, leading to the formation of the Oued (River) Zyatine basin with a syntectonic Quaternary deposits. We used the gravity data analysis to mark the thicknesses of syntectonic deposits and their bounding thrust faults. The kinematic analysis indicates the occurrence of progressive multiphase out-of-sequence thrusting events with thrusts verging to the southeast. The combination of climate and mechanical fractures induced gradually long-term damage and changed the original landscape of the evidenced out-of-sequence thrusts. Furthermore, the existence of local normal faults in the backlimbs and reverse faults in the forelimbs, together with the drainage network type, earthquakes, the slope erosion, and the aggraditional terrace system, implies a gradual landscape evolution of thrust topography. This physical evolution occurred following an active tectonics across the exhibited out-of-sequence thrusting since the Pliocene.

Hydrological evaluation of conservation bench terrace system in outer foothills of Himalayas using soft computing techniques

Soil erosion has been problematic in the outer foothills of the Himalayas. Therefore, it is necessary to implement suitable conservation measures to check erosion issues. The present study experimented on conservation bench terraces (CBT) as a conservation measure in the outer foot Himalayas in Dehradun, India. The study evaluates the effectiveness of different CBTs of embankment heights 10 cm (CBT-10), 15 cm (CBT-15), and 20 cm (CBT-20) to runoff and soil loss under different rainfall storms. Further, the estimation of Soil loss (Sloss) was evaluated using soft computing techniques (machine learning models). The soft computing techniques were applied to the data obtained from CBT plots for hydrological assessment. The methods used for analysis were support vector machine (SVM), Bagging, and Random Forest (RF) models. The performance of developed models was evaluated using mean absolute error (MAE), root mean square error (RMSE), Nash-Sutcliffe efficiency (NSE), Pearson's correlation coefficient (PCC), and Wilmott Index (WI) along with graphical representation (Scatter plot and Taylor diagram). The results showed that the CBT techniques were observed to reduce runoff and soil loss. Among CBT, CBT-20 was the most significant as the number of runoff events was less than others. Considering the storm size, the maximum percentage of runoff generated from the storm size is more important than 100 mm. Moreover, soil loss (Sloss) estimation showed that the SVM models perform better in all three scenarios, which are results of three scenarios such as R2 = 0.50, 0.52 and 0.80; MAE = 0.03, 0.03 and 0.10; RMSE = 0.08, 0.07 and 0.27; NSE = 0.39, 0.12 and 0.21; PCC = 0.71, 0.725 and 0.89; and WI = 0.67, 0.794, and 0.49, respectively. Therefore, SVM techniques can be applied to the estimation of Sloss. Results can be recommended for precision farming under climate changes in the hilly and plain areas and similar models can be applied to other areas.

Multi-sensor drone survey of ancestral agricultural landscapes at Picuris Pueblo, New Mexico

Although aircraft-acquired lidar has proven to be a transformative technology for archaeology in forested regions around the world, drone-acquired lidar systems that could potentially offer higher-resolution imagery at much lower cost remain difficult to deploy in field settings, while the data they produce are prone to large errors and are challenging to process. This paper presents results of a study that employs a new ultra-compact drone-based lidar system, alongside aerial thermal and visible light imaging, to document ancient agricultural landscapes at Picuris Pueblo, New Mexico. We discuss the advantages of this new instrumentation, various approaches to field data collection, and as well as our novel data processing and filtering methods, which collectively offer key methodological advances for archaeological investigations using drone-based lidar. Results reveal extensive remains of a vast system of terraces and stone-built field systems, preserved below the modern piñon-juniper-ponderosa forests of the Picuris Reservation and surrounding areas. These findings offer new perspectives on the scale and intensity of past agricultural activities in this highland region of the American Southwest, while demonstrating the power of combining multiple drone-based remote sensing datasets with detailed surface surveys to aid in the discovery, mapping, and interpretation of archaeological landscapes in forested regions.

An integrated mechanism and challenges of mountainous sustainable development: A review of Hani Terraces, China

AbstractMountainous agriculture supports 15% of the global population, but its sustainability is facing challenges with the social transition. Honghe Hani Rice Terrace System (HHRTS), China, a double world‐level heritage, performs strong resilience to challenges. Available studies on HHRTS examines its sustainability from some perspectives but lack a systemic elaboration on its sustainable mechanism. This study extensively examines the literature on HHRTS and offers a comprehensive analysis of its sustainability. The findings suggest that mountainous agricultural sustainability depends on the support from relatively enough water and land resources and diverse employment based on these resources (economic sustainability), the environmental stability based on reasonable landscape structure, rich biodiversity and ecological farming methods (environmental sustainability), and social stability based on the well‐developing social structure, efficient management system, and relevant cultural restraint and guidance (social sustainability) as well as the dynamic interaction among the three dimensions. Among them, traditional knowledge and cultures play a positive role in maintaining the stability of terraced landscapes, but their role is weakening with industrialization and urbanization. This study provides a systemic explanation of a dynamic evolution mechanism that the economic and social factors drive local people to maintain a mountainous agricultural system from the agricultural society to the industrial society based on the theory of planned behavior. This study also provides abundant local knowledge, experiences, and an analytical framework for reconstructing a sustainable mountainous agricultural system in the socio‐economic transformation stage.

Investigating optical dating of carbonate-rich cobbles from a river terrace: A pilot study from the Mula Valley, Spain

Rock surface luminescence dating has emerged as a powerful geochronological tool; however, the method requires lithologies containing sufficient amounts of quartz or feldspar grains. The application of burial dating to fluvial cobbles, containing only sparse amounts of feldspars, is evaluated in calcarenite cobbles collected in the Mula valley, Spain. Two sampled cobbles demonstrated sufficient luminescence sensitivity. We extracted three or more drill cores from each cobble surface and subsequently measured the sensitivity-corrected luminescence signal with depth using an IRSL/pIRIR protocol to target feldspar grains in calcarenites. We observed significant luminescence-signal depth variations between the cores collected from the same rock surface, suggesting the value of measuring several cores. None of the top surfaces has been significantly bleached; therefore, they convey no relevant age data. Cores from the bottom surfaces show evidence of bleaching in the first 1 to 3 mm, but generally, only the surface slices can be used for dating. One core from each cobble displays a short, non-saturated dose plateau near the surfaces; the modelling demonstrates that the surface slices from these cores contained negligible doses before burial. The age estimate for the bottom surfaces mainly falls into two groups: 24–38 ka and 11–16 ka. The older age group is within the expected age range, previously dated with radiocarbon on another outcrop of the same terrace system. However, the signal-depth profiles indicate that the younger date is more reliable than the older date. Currently, no geomorphological explanation exists to explain the younger-than-expected ages.

Genetic Diversity and Association Mapping of Grain-Size Traits in Rice Landraces from the Honghe Hani Rice Terraces System in Yunnan Province.

The Honghe Hani Rice Terraces System (HHRTS) of Yunnan Province is an important agricultural and cultural heritage landscape. Until now, a large number of local rice landraces have been planted. Mining excellent genes contained in these landraces provides a reference for variety improvement and new variety breeding. In this study, 96 rice landraces collected from the Hani terraces were planted in Honghe Mengzi, Yunnan Province, in 2013, 2014, 2015, and 2021, and five major grain traits were measured and analyzed. The genomic variation of 96 rice landraces was scanned by 201 simple sequence repeat (SSR) markers. The genetic diversity, population structure, and genetic relationships of the natural population were analyzed. The mixed linear model (MLM) method of the TASSEL software was used to analyze the associations between markers and traits. A total of 936 alleles were amplified by 201 pairs of SSR primers. The average number of observed alleles (Na), the effective number of alleles (Ne), Shannon's information index (I), heterozygosity (H), and the polymorphism information content (PIC) per marker were 4.66, 2.71, 1.08, 0.15, and 0.55, respectively. Ninety-six landraces were divided into two groups by population structure, clustering, and principal component analysis, and indica rice was the main group. The coefficients of variation of the five traits ranged from 6.80 to 15.24%, and their broad heritabilities were more than 70%. In addition, there were positive correlations among the same grain traits between different years. Through MLM analysis, 2, 36, 7, 7, and 4 SSR markers were significantly associated with grain length (GL), grain width (GW), grain thickness (GT), grain length-width ratio (LWR), and thousand-grain weight (TGW), respectively. The explanation rates of phenotypic variation were 16.31 (RM449, Chr. 1)-23.51% (RM316, Chr. 9), 10.84 (RM523, Chr. 3; RM161/RM305, Chr. 5)-43.01% (RM5496, Chr. 1), 11.98 (RM161/RM305, Chr. 5)-24.72% (RM275, Chr. 6), 12.68 (RM126, Chr. 8)-36.96% (RM5496, Chr. 1), and 17.65 (RM4499, Chr. 2)-26.32% (RM25, Chr. 8), respectively. The associated markers were distributed on 12 chromosomes of the genome.