Abstract. Runoff (R) generation in Mediterranean headwater catchments is highly episodic and shaped by the interplay of precipitation (P), seasonal soil moisture (SM) dynamics, and terrain structure. In terraced landscapes, land abandonment has driven a forest transition that increases fuel loads and wildfire occurrence, while legacy features such as stone walls modify storage and flow pathways, affecting hydrological spatial coupling. Wildfires further reduce vegetation cover, induce soil water repellence, and lower infiltration capacity, enhancing R generation and reorganising connectivity during a post-fire window of disturbance, but their interaction with terrace structure at event scale is poorly understood. This study investigates how P, seasonal evolving SM, and terrain structure control R in a 4.7 ha terraced microcatchment in Mallorca, Spain, affected by a high-severity wildfire in 2013. Hydrological conditions were classified into four periods (wet, drying-down, dry, and wetting-up). P, SM, and discharge (Q) were continuously monitored over four years (2021–2024), with SM measured at representative hillslope and terrace locations. Of 186 P events analyzed, only 17% generated measurable outlet Q, with R highly concentrated in time: November 2021 alone accounted for 73% of total R volume. Maximum SM consistently emerged as the strongest indicator of R occurrence across seasons, while event-scale changes in SM (ΔSM) were particularly informative during transitional periods; antecedent SM showed limited predictive power, especially under partially coupled conditions. Hillslopes responded rapidly to P but with weak coupling between local SM and outlet Q, whereas farm terraces exhibited storage-controlled behaviour in well-connected positions and delayed or suppressed responses in disconnected mid-terrace areas. Overall, R emerges from the interaction between P forcing, dynamically evolving SM, and spatially variable structural connectivity, rather than from static thresholds, highlighting the need for connectivity-aware, event-scale approaches to inform land management in Mediterranean landscapes under global change.

Regime shifts from grassland to shrubland are a key feature of dryland degradation, yet the role of connectivity in understanding these transitions remains poorly quantified. Using a numerical model, we simulate vegetation change from 1895 to 2022 under two climate endmembers bracketing the regional aridity gradient: a dry extreme (Southwest Arizona) and a wet extreme (Northern Plateau New Mexico). Under near-natural grazing (1 g/m²/year), grass biomass remained stable with negligible shrub presence. Moderate grazing (30%) initiated shrub emergence by 1930 in dry climates, while wetter systems largely retained grass (>20 g/m²). High grazing (60%) drove abrupt, near-total grass loss, with shrub biomass exceeding 40 g/m² in dry and ∼60 g/m² in wet climates. Connectivity metrics strongly predicted shrub expansion, with structural and functional connectivity of water and nitrogen correlating up to 0.96 with shrub biomass, providing early-warning signals 4 to 16 years before vegetation shifts. By moving beyond static biomass measures and incorporating connectivity dynamics, this study advances predictive understanding of grass-shrub regime shifts and offers a scalable approach for dryland management under intensifying global change.

The Ottoman Empire expanded from northwest Anatolia to large areas of the Middle East, north Africa and southeast Europe in the 250 years after 1300 CE, and continued until the early 20th century. Water management was a significant issue in the empire, not least because it covered many dryland areas. Taxation systems supporting the Empire were directly related to crop production and hence water management played a central role, although responsibility for it seems to have been devolved to local actors, leading to debates on the overall organization of the Empire. In this study, we address questions of how water was managed in the Konya Plain of Central Türkiye, which came under Ottoman rule from 1468 CE, in order to assess whether relative proximity to the Imperial centre and local conditions affected the approaches taken. We use records from Şer’i (Sharia) and Örf’i (customary) laws to evaluate the ways in which water management was regulated. There are eleven Konya şer’iyye registers dating from 1595 to 1922, and five sets of kanannume or ledgers of customary law dating to the 16th century CE. We use comparative evidence from taxation registers from the 16th and 19th centuries, as well as information obtained from remote sensing and landscape analysis. Structures for managing water such as artificial channels, wells, storage structures and watermills are commonly mentioned in the records. Only the very largest structures or systems relating to pilgrimage routes were managed directly by the state by delegation to a mirab or “watermaster”. Most features were managed locally by individuals, villages, religious foundations or artisanal guilds. Precedence was an important part of dispute resolution supervised by a judge (kadı), and allocations of water by turns (nöbet) which seem to have been already in place before the Ottoman period. There was also a specific style of management called suğlas based on local intensive irrigation with dams to store and divert water, which were more productive and taxed more highly than other irrigated land, which was in turn taxed more highly than non-irrigated land. The management of water in the Konya Plain had important similarities and differences from known practices elsewhere in the Ottoman Empire. Of the former, the delegation to local controls and precedence for pre-Ottoman practices are amongst the most important, together with the use of a legal system for local dispute resolution. The extent of the suğlas and the importance of the mirab seem to be key differences with other well-studied areas. The practice of water management was highly resilient in this water-sparse region, based on local delegation that seems to support the hub-and-spoke model of how the Ottoman Empire operated.

The ability of urban centres to grow and persist through crises is often assessed qualitatively in archaeology but quantitative assessment is more elusive. Here, the authors explore urban resilience in ancient Mesopotamia by applying an adaptive cycle framework to the settlement dynamics of the Bronze and Iron Age Khabur Valley (c. 3000-600 BC). Using an integrated dataset of settlements and hollow ways, they identify patterns of growth, conservation, release and reorganisation across six periods, demonstrating the value of coupling archaeological data with resilience theory and network analysis to understand the adaptive capacities of complex archaeological societies.

Abstract River connectivity is essential for maintaining fertile floodplains, healthy ecosystems, and human activities, particularly in semi‐arid regions, where water flow is often intermittent. Despite its importance, very few studies have attempted to quantify connectivity at the scale of individual rainfall‐runoff events. In this study, we present a novel framework for exploring synchronous and sequential connectivity to capture the hydrological response of a system. We distinguish between structural (SC) and functional (FC) connectivity by constructing structural networks utilizing topographic data from the Walnut Gulch Experimental Watershed in Arizona, USA, and correlation‐based functional networks using high‐resolution runoff data. We examine how SC‐FC relations vary across events and how they relate to the hydrological responses of the system. We classify rainfall events via unsupervised clustering and identify the corresponding dominant runoff connectivity patterns within each cluster. The results of our analysis showed that short, intense storms tend to produce localized runoff connectivity, characterized by dominant synchronous SC‐FC relations, whereas larger rainfall events tend to exhibit higher sequential SC‐FC correlation values, indicating widespread system connectivity. Furthermore, our analysis revealed that there is a minimum threshold in the synchronous connectivity value (0.13), before positive sequential activity appears in the system. Comparable synchronous and sequential connectivity values typically indicate that water flow reached the watershed outlet; however, maximum SC‐FC value is not necessarily associated with peak discharge at the watershed outlet. Due to its flexibility, our approach suggests a general framework for analyzing connectivity in any river network with an ephemeral flow regime.

Networks are increasingly used to describe and analyse complex archaeological data in terms of nodes (archaeological sites or places) and edges (representing relationships or connections between each pair of nodes). Network analysis can then be applied to express local and global properties of the system, including structure (e.g. modularity) or connectivity. However, the usually high amount of missing data in archaeology and the uncertainty they cause make it difficult to obtain meaningful and robust results from the statistical methods utilised in the field of network analysis. Hence, we present in this paper manual and computational methods to (1) fill gaps in the settlement record and (2) reconstruct an ancient route system to retrieve a network that is as complete as possible. Our study focuses on the sites and routes, so-called hollow ways, in the Khabur Valley, Mesopotamia, during the Bronze and Iron Age as one of the most intensively surveyed areas worldwide. We were able to predict additional sites that were missing from the record as well as develop an innovative hybrid approach to complement the partly preserved hollow way system by integrating a manual and computational procedure. The set of methods we used can be adapted to significantly enhance the description of many other cases, and with appropriate extensions successfully tackle almost any archaeological region.

Analysing and understanding connectivity of human social networks of (ancient) societies offers new perspectives on their functioning. However, social network approaches in archaeology rarely utilise formal statistical models to test established theories or develop new hypotheses. In this paper, we present the implementation of MCMC-MLE Temporal Exponential Random Graph Models (MTERGMs) to investigate the hollow way network between settlements of the Bronze and Iron Age Khabur Valley, Mesopotamia. Using MTERGMs, we evaluate eight hypotheses to assess which network patterns explain the formation of the hollow ways. Our results show that in the cross-sectional networks, preferential attachment, transitivity, distance and site size are important factors for tie formation while the longitudinal analysis reveals tie persistence over time with distance and transitivity being significant for tie formation. We reflect on these findings as well as the limitations of our dataset and conclude that MTERGMs are useful tools to formally evaluate archaeological theories pertaining to network structures and processes, if the available data are sufficiently complete.

Quantifying connectivity patterns in dryland ecosystems enables us to understand how changes in the vegetation structure influence the runoff and erosion processes. This knowledge is crucial for mitigating the impacts of climate change and land use modifications. We quantify the multi-scale water-mediated connectivity within grassland and shrubland hillslopes using a weighted, directed network model. By integrating high-resolution elevation data, vegetation information, and modeled event-based hydrologic and sediment transport, we assess both structural connectivity (physical landscape layout) and functional connectivity (dynamic water and sediment movement) under varying rainfall and soil moisture conditions. Our findings reveal a marked increase in local (patch-scale) connectivity metrics in shrublands compared to grasslands. Metrics like betweenness centrality-which measures the importance of nodes in connecting different parts of the network-and the weighted length of connected pathways increase up to tenfold in shrublands. Despite substantial local changes, global (plot-scale) properties like efficiency of water and sediment transfer show less variation, suggesting a robust network topology that sustains geomorphic functionality across different vegetation states. We also find that the functional connectivity is more strongly correlated with structural connectivity for sediment than for water. This difference is particularly pronounced under high rainfall conditions and shows little sensitivity to variations in antecedent soil moisture, highlighting the critical role of rainfall-driven processes in shaping connectivity patterns. The study offers a comprehensive framework for analyzing connectivity at multiple scales, which can inform targeted management strategies aimed at enhancing ecosystem resilience, such as interventions to control erosion or restore vegetation patterns.

This article elaborates on an artist-in-residence project funded by the Leverhulme Trust in the Geography Department at Durham University in 2015–16. The project confronted artistic and scientific perspectives to investigate how people in the North-East of England perceive and value their river environments and to recognize potential contributions to catchment management. The project identified a variety of disconnexions and hierarchies in the River Wear catchment and formulated artistic interventions for nonhuman audiences. This article reflects on water holistically and explores transdisciplinary views to propose water in its expanded field. Water in the Expanded Field is plural, complex, and aims at decentering the human importance. It promotes water multiple perspectives, including the more-than-human world and acknowledging water’s ontological importance, developed by the speculative artistic practice of producing works of art for nonhuman audiences and then transposed to water debates. The article converges distinct evidence pointing to the importance of composting existing knowledge and dualistic reasoning to promote pluriversal ontologies of water.

This study investigates the use of planform sinuosity as a metric to produce an automatic classification of waterways in the pre-modern and present-day irrigation networks in the Konya Plain in south-central T & uuml;rkiye. Results show that such automatic classification may replace a time-consuming manual classification or provide a preliminary classification for subsequent manual refinement, depending on the number of classification categories used, the distribution of sinuosity across the network, and the degree of human modification. They also show that sinuosity thresholds for classification are area- and time-specific. Sinuosity is then used to quantify and interpret network changes in planform alignment and expansion and to identify long-term trends and areas of landscape modification. Results reveal a general pattern of decreasing sinuosity over time in the Konya Plain, indicating a continual human intervention, with areas where the present-day network was built upon the old Ottoman system. The methods presented in this investigation may be applicable to other studies of irrigation-network evolution and impact on landscape and can be used in conjunction with archeological and historical analysis.

Context Neutral landscape models generate virtual landscapes that enable computer-based exploration of the effects of spatial patterns on ecological processes free from the restrictions of real-world experimentation. For some questions in landscape ecology it is critical to incorporate human landscape features, such as networks, that are an integral part of human-influenced landscapes. Objectives This paper outlines an approach to produce a neutral landscape model that uses the human geography principle of least-cost movement to create a network of human sites (buildings, camps, mines, settlements, farms, factories, etc.) and routes (trails, roads, railways, canals, powerlines, etc.). Methods We used a least-cost modelling framework to create sites prioritised on least-cost catchment areas and routes based on least-cost paths. The location of sites and routes is determined by an underlying cost-surface that defines how movement costs vary across the landscape. The range of possible network patterns was quantified via raster network metrics and was compared to real-world network data. Results The proposed neutral landscape model produces networks with a wide range of possible patterns, and using real-world data can guide the selection of parameters that mimic human activity in a variety of land cover classes in real-world landscapes. Conclusions This network neutral landscape model extends the potential of neutral landscape models for research into human-influenced landscapes. We provide the code used to generate our examples under a permissive open-source licence.

This study provides a new perspective on understanding the intricacies of water-mediated connectivity in ecosystems, bridging landscape ecology and geomorphology through network science. We highlight dryland and river-floodplain ecosystems as distinct examples of contrasting water-controlled systems. We (1) discuss central considerations in developing structural connectivity and functional connectivity networks of water-mediated connectivity; (2) quantify the emergent patterns in these networks; and (3) evaluate the capacity of network science tools for investigating connectivity characteristics. With a focus on strength (weights) and direction, connectivity is quantified using seven parameters at both network and node levels. We find that link density, betweenness centrality and page rank centrality are highly sensitive to directionality; global efficiency and degree centrality are particularly sensitive to weights; and relative node efficiency remains unaffected by weights and directions. Our study underscores how network science approaches can transform how we quantify and understand water-mediated connectivity, especially in consideration of the role(s) of weights and directionality. This interdisciplinary perspective, linking ecology, hydrology and geomorphology, has implications for both theoretical insights and practical applications in environmental management and conservation efforts.

Fine-sediment input into river networks presents one of the biggest environmental pressures in agricultural catchment systems due to accelerating soil erosion rates associated with agricultural practices. To understand and effectively manage this problem, it is essential to identify sediment source areas and the pattern of linkages between different landscape compartments along the sediment pathways that ultimately end up in the river channel. Sediment connectivity is an increasingly used concept to help assess both on-site and off-site impacts of soil erosion by describing the efficiency of fine-sediment transfer through these different zones. Natural Water Retention Measures (NWRM) that emulate natural processes to enhance or restore the water retention capacity of ecosystems, available to be applied at agricultural fields, can be understood within this framework as they modify connectivity and provide benefits that include erosion and sediment control. The aim of this study is to assess the differences in sediment connectivity associated with scenarios of different NWRM (e.g. buffer strips, strip cropping, terracing, mulching) in a selected hillslope of the Fugnitz Catchment (Austria). Using a process-based sediment-transport model (MAHLERAN; Wainwright et al., 2008), runoff and sediment transport were dynamically simulated. Simulation results of water and sediment fluxes were then translated into a graph representing the flow network, consisting of nodes and edges, where connectivity and network properties can be quantified using graph-theoretical metrics (e.g. betweenness centrality). The same workflow was used for other NWRM scenarios, modifying parameters of the sediment transport model to capture the NWRM conditions. The results show notable changes in connectivity between scenarios as well as varying patterns of hot spots where sediment delivery is high and where interventions may be targeted, thus providing options of agricultural practices that can be implemented to improve sustainability in agricultural catchments.

Small mountainous rivers (SMRs) produce about 40% of the world’s sediment discharge from land to ocean. The dominant sources of this sediment are earthquake and typhoon-driven landslides. It is widely accepted that earthquake-induced landslides tend to locate at hillslopes, while typhoon-induced landslides tend to cluster at hillslope toe areas. These differences in landslide drivers and landslide location together determine the connectivity of resulting sediment transfers from the source (landslides) to the river network. Therefore, understanding when and where earthquake and typhoon-driven landslides occur, and the pathways and timescales over which these sediment sources are connected to river channels can help us determine the relative controls of earthquakes and typhoons on sediment discharge in SMRs. Here, we illustrate how detailed spatial and temporal mapping of landslides, using Landsat imagery within Google Earth Engine, enables us to better understand sediment connectivity in SMRs, and improve our understanding of the controls on sediment discharge in SMRs. We focus our analysis on the period between 1999 and 2020, which includes the 1999 Chi-Chi earthquake (Mw=7.7) and typhoon Morakot, which generated over 3000 mm of rainfall between 5th and 10th August 2009. The results show that we can identify event-induced landslide areas at a higher temporal resolution than the open-source landslide dataset from the Forest Bureau, Taiwan, which enables us to refine our understanding of the relative controls of discrete events (i.e. earthquakes and typhoons) on landslides and connected sediment transport pathways, and determine the timescales over which they lead to elevated sediment discharge in SMRs. Refining our understanding of earthquake and typhoon-driven controls on landslides in SMR catchments and cascading impacts on sediment export from SMRs is particularly important given the recent intensification of rainfall intensities that are anticipated to continue in the future.

Andrew Sherratt's 'Water, soil and seasonality', World Archaeology (1980), signposted a long-term debate surrounding early farming adaptations to riverine landscapes in western Asia and Europe. Recent research at catalhoyuk in central Anatolia, a key case study in Sherratt's 'floodplain cultivation' model, enables integrated, evidence-based assessment of the local hydrology and agroecology, and of farmers' resilience over more than a millennium. In contrast to previous models, the agroecological niche at catalhoyuk featured strategic planting of diverse crops across a range of hydrological conditions, within and beyond a broad 'belt' of small anastomosing river channels extending a kilometre from the site. Growing conditions likely depended on location relative to settlement, a nutrient-rich 'hot spot', with diminishing inputs of organic matter and mechanical disturbance away from the tell. This reconstruction contrasts with the original model of 'floodplain cultivation' and demonstrates the complexity with which agroecologies evolved through landscape affordances, creative cropping, and resilience.