Challenges of mapping, modelling and quantifying sediment connectivity

Intra-annual sediment dynamic assessment in the Wei River Basin, China, using the AIC functional-structural connectivity index

“…As Hooke and Souza (2021) mentioned, validation of the results of sediment connectivity indices is still one of the major challenges in assessing and quantifying connectivity. Some studies have compared or validated connectivity in small catchments (less than 260 km 2 ) using field mapping (Messenzehl et al, 2014;Nicoll and Brierley, 2017), but in a large river basin like the Wei river basin this task is challenging, since the connection of every part of the system need to be assessed, thus in this study we assessed the correlation of sediment yield and functional connectivity as an attempt to validate the results, 15 stations showed significant positive correlation among 23 watersheds, 8 stations showed insignificant correlation due to the sediment yield of these stations peak in July and August within the year while AIC peak in Aril, June and August (Fig.…”

“…Sediment connectivity is a promising concept in erosion research, addressing the sediment transfer from sources to sinks within a system (Wohl et al, 2019;Hooke and Souza 2021), and the response of the system to both external and internal forces, such as climate change and anthropogenic structures (Lisenby et al, 2019). Connectivity can be divided into two categories: structural connectivity and functional connectivity (Turnbull et al 2008;López-Vicente et al, 2016;Cossart and Fressard 2017).…”

“…Structural connectivity represents the physical linkages of the system at a certain point in timeusually using long term annual mean values, while functional connectivity relates to dynamic processesthe transfer of water and sediment through the system over a specific period in time (Heckmann et al, 2018). Connectivity is often estimated by using modelling approaches, such as graph theory-based network analysis and connectivity indices (Hooke and Souza, 2021). Indices can present one or a few proxy variables such as topographic characteristics, network structure, and vegetation characteristics that would affect connectivity (Bracken et al, 2015).…”

Structural Hillslope Connectivity Is Driven by Tectonics More Than Climate and Modulates Hydrologic Extremes and Benefits

“…However, this kind of dynamic connectivity model requires considerable data and modeling resources, which are underdeveloped at continental scales. We suggest building upon existing connectivity models, for example, CASCADE (CAtchment Sediment Connectivity And DElivery model) (Hooke & Souza, 2021; Schmitt et al., 2016; Tangi et al., 2019), to expand into new spatiotemporal scales and geomorphological domains. Advancements in high‐performance computing and deep learning algorithms are making these kinds of efforts more viable than ever before (Razavi, 2021; Sit et al., 2020).…”

Relevance of field data in the assessment of structural and functional sediment connectivity in a small catchment of southern Brazilian plateau

“…The dynamics of sediment delivery and deposition in a catchment is controlled by (de)couplings of source areas, which are (de)activated by natural erosion agents (e.g., rain and runoff) or anthropic actions (e.g., dam and road constructions). Currently, studies about connectivity seek to establish techniques and methods to quantify it (Heckmann et al, 2018; Hooke & Souza, 2021; Keesstra et al, 2018). Thus, it is necessary to explore which are the governing agents and phenomena in different landscapes.…”