Concepts of hydrological connectivity: Research approaches, pathways and future agendas

Abstract

. (2013) 'Concepts of hydrological connectivity : research approaches, pathways and future agendas.', Earth-science reviews., 119 . pp. 17-34. Further information on publisher's website:http://dx.doi.org/10.1016/j.earscirev.2013.02.001Publisher's copyright statement: NOTICÅ: this is the author's version of a work that was accepted for publication in Earth-Science Reviews. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reected in this document. Changes may have been made to this work since it was submitted for publication. A denitive version was subsequently published in Earth-Science Reviews, 119, 2013Reviews, 119, , 10.1016Reviews, 119, /j.earscirev.2013.001. Additional information:Use policyThe full-text may be used and/or reproduced, and given to third parties in any format or medium, without prior permission or charge, for personal research or study, educational, or not-for-prot purposes provided that:• a full bibliographic reference is made to the original source • a link is made to the metadata record in DRO • the full-text is not changed in any way The full-text must not be sold in any format or medium without the formal permission of the copyright holders.Please consult the full DRO policy for further details. to direct future research into process-based hydrological connectivity this paper: i) evaluates the 20 extent to which different concepts of hydrological connectivity have emerged from different 21 approaches to measure and predict flow in different environments; ii) discusses the extent to which 22 these different concepts are mutually compatible; and iii) assesses further research to contribute to 23 a unified understanding of hydrological processes. Existing research is categorised into five different 24 approaches to investigating hydrological connectivity: i) evaluating soil -moisture patterns (soil-25 moisture connectivity); ii) understanding runoff patterns and processes on hillslopes (flow -process 26 connectivity); iii) investigating topographic controls (terrain-connectivity) including the impact of 27 road networks on hydrological connectivity and catchment runoff; iv) developing models to explore 28 and predict hydrological connectivity; and v) developing indices of hydrological connectivity . Analysis 29 of published research suggests a relationship between research group, approach, geographic setting 30 and the interpretation of hydrological connectivity. To further understanding of hydrological 31 connectivity our knowledge needs to be developed using a range of techniques and approaches, 32 there should be common understandings between researchers approaching the concept from 33 different perspectives, and these meanings need to be communicated effectively with those 34 responsible for land management. 35 36

Sediment connectivity: a framework for understanding sediment transfer at multiple scales

“…The developments in hydrological connectivity were driven partly by calls for new ways of thinking about runoff and hydrological process conceptualization in heterogeneous landscapes (McDonnell, 2003;Ambroise, 2004;McDonnell et al, 2007). Hydrological connexions via overland and subsurface flows have become conceptualized as a function of water volume (supplied by rainfall and runon, depleted by infiltration, evaporation, transpiration and transmission losses) and rate of transfer (a function of pathway, hillslope length and flow resistance) (Bracken et al, 2013). These processes interact with flow resistance, varying as a function of flow depth, which establishes a feedback between rainfall, infiltration and flow routing which produces the nonlinearity seen in river hydrographs and scale-dependence of runoff coefficients (Wainwright and Bracken, 2011).…”

“…Each zone contains two parts: the morphologic system (the landforms) and the cascading system (the energy and materials flowing through that zone) (Chorley, 1971;Schumm, 1981). A major limitation of previous discussions of 'connectivity' is an unclear definition of the meaning of the term within the context in which it is used (Bracken et al, 2013). In a geomorphic system, connectivity may occur through the physical contact between two zones, through the transfer of material between zones, or both (Jain and Tandon, 2010).…”

“…Sediment connectivity is based on the interplay of structural components (morphology) and process components (flow of energy/transport vectors and materials) that determine the longterm behaviour of the sediment flux which is manifest as a change in landform (Preston and Schmidt, 2003;Turnbull et al, 2008;Bracken et al, 2013). Thus, sediment connectivity is dependent not on individual processes, but on all aspects of the geomorphic system that control sediment flux -processes of detachment, entrainment and transport -but also the emergent characteristics of sediment deposition and sediment residence times (Preston and Schmidt, 2003;Sandercock and Hooke, 2011).…”

Managing ditches for agroecological engineering of landscape. A review

“…The designs of ditch networks, including reach morphology, reach branching, and density, are also strongly related to the runoff capture efficiency (Levavasseur et al 2012;Zhang et al 2013). Moreover, it is expected that the influence of plotstream connections on runoff interception (Bracken et al 2013) is similar to that of plot-ditch connections, although this has not been demonstrated.…”

Calculation of Wetlands Ecological Water Requirement in China’s Western Jilin Province Based on Regionalization and Gradation Techniques

“…Hydrological connectivity is the basis of water supply and allocation; it should be the first to be analyzed in quantitative studies of how waterways in neighboring regions can be connected in water management. Bracken et al (2013) classified the research around hydrological connectivity into five broad themes based on: i) soil moisture; ii) flow processes; iii) terrain; iv) models; and v) indices. This classification yielded a definition of hydrological connectivity, and laid a foundation of conceptualization and methodology of different research approaches.…”