Modelling catchment-scale shallow landslide occurrence by means of  a subsurface flow path connectivity index

Abstract. Topographic index-based hydrological models have gained wide use to describe the hydrological control on the triggering of rainfall-induced shallow landslides at the catchment scale. A common assumption in these models is that a spatially continuous water table occurs simultaneously at any point across the catchment. However, during a rainfall event isolated patches of subsurface saturation form above an impeding layer and hydrological connectivity of these patches is a necessary condition for lateral flow initiation at a point on the hillslope. Here, a new hydrological model is presented, which allows to account for the concept of hydrological connectivity while keeping the simplicity of the topographic index approach. A dynamic topographic index is used to describe the transient lateral flow that is established at a hillslope element when the rainfall amount exceeds a threshold value allowing for (a) development of a perched water table above an impeding layer, (b) hydrological connectivity between the hillslope element and its own upslope contributing area. A spatially variable soil depth is the main control of hydrological connectivity in the model. The hydrological model is coupled with the infinite slope stability model, and with a scaling model for the rainfall frequency-duration relationship to determine the return period of the critical rainfall needed to cause instability on three catchments located in the Italian Alps. The results show the good ability of our model in predicting observed shallow landslides. The model is finally used to determine local rainfall intensity-duration thresholds that may lead to shallow landslide initiation.

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Modelling shallow landslide susceptibility by means of a subsurface flow path connectivity index and estimates of soil depth spatial distribution

Hydrology and Earth System Sciences ◽

10.5194/hess-16-3959-2012 ◽

2012 ◽

Vol 16 (11) ◽

pp. 3959-3971 ◽

Cited By ~ 35

Author(s):

C. Lanni ◽

M. Borga ◽

R. Rigon ◽

P. Tarolli

Keyword(s):

Spatial Distribution ◽

Water Table ◽

Hydrological Model ◽

Soil Depth ◽

Shallow Landslides ◽

Lateral Flow ◽

Necessary Condition ◽

Hydrological Connectivity ◽

Topographic Index ◽

Infinite Slope Stability Model

Abstract. Topographic index-based hydrological models have gained wide use to describe the hydrological control on the triggering of rainfall-induced shallow landslides at the catchment scale. A common assumption in these models is that a spatially continuous water table occurs simultaneously across the catchment. However, during a rainfall event isolated patches of subsurface saturation form above an impeding layer and their hydrological connectivity is a necessary condition for lateral flow initiation at a point on the hillslope. Here, a new hydrological model is presented, which allows us to account for the concept of hydrological connectivity while keeping the simplicity of the topographic index approach. A dynamic topographic index is used to describe the transient lateral flow that is established at a hillslope element when the rainfall amount exceeds a threshold value allowing for (a) development of a perched water table above an impeding layer, and (b) hydrological connectivity between the hillslope element and its own upslope contributing area. A spatially variable soil depth is the main control of hydrological connectivity in the model. The hydrological model is coupled with the infinite slope stability model and with a scaling model for the rainfall frequency–duration relationship to determine the return period of the critical rainfall needed to cause instability on three catchments located in the Italian Alps, where a survey of soil depth spatial distribution is available. The model is compared with a quasi-dynamic model in which the dynamic nature of the hydrological connectivity is neglected. The results show a better performance of the new model in predicting observed shallow landslides, implying that soil depth spatial variability and connectivity bear a significant control on shallow landsliding.

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Shallow landslide prediction in the Serra do Mar, São Paulo, Brazil

Natural Hazards and Earth System Science ◽

10.5194/nhess-10-1829-2010 ◽

2010 ◽

Vol 10 (9) ◽

pp. 1829-1837 ◽

Cited By ~ 45

Author(s):

B. C. Vieira ◽

N. F. Fernandes ◽

O. A. Filho

Keyword(s):

Sao Paulo ◽

Shallow Landslide ◽

Shallow Landslides ◽

Southeastern Brazil ◽

Mountain Range ◽

São Paulo ◽

Catchment Scale ◽

Landslide Prediction ◽

Serra Do Mar ◽

Number Of Cells

Abstract. Various methods are currently used in order to predict shallow landslides within the catchment scale. Among them, physically based models present advantages associated with the physical description of processes by means of mathematical equations. The main objective of this research is the prediction of shallow landslides using TRIGRS model, in a pilot catchment located at Serra do Mar mountain range, São Paulo State, southeastern Brazil. Susceptibility scenarios have been simulated taking into account different mechanical and hydrological values. These scenarios were analysed based on a landslide scars map from the January 1985 event, upon which two indexes were applied: Scars Concentration (SC – ratio between the number of cells with scars, in each class, and the total number of cells with scars within the catchment) and Landslide Potential (LP – ratio between the number of cells with scars, in each class, and the total number of cells in that same class). The results showed a significant agreement between the simulated scenarios and the scar's map. In unstable areas (SF≤1), the SC values exceeded 50% in all scenarios. Based on the results, the use of this model should be considered an important tool for shallow landslide prediction, especially in areas where mechanical and hydrological properties of the materials are not well known.

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Development of a data-driven model for spatial and temporal shallow landslide probability of occurrence at catchment scale

Landslides ◽

10.1007/s10346-020-01592-3 ◽

2020 ◽

Author(s):

M. Bordoni ◽

V. Vivaldi ◽

L. Lucchelli ◽

L. Ciabatta ◽

L. Brocca ◽

...

Keyword(s):

Roc Curve ◽

Dynamic Change ◽

Joint Probability ◽

Shallow Landslide ◽

Shallow Landslides ◽

Multivariate Adaptive Regression Splines ◽

Data Driven ◽

Catchment Scale ◽

Probability Of Occurrence ◽

Area Under Roc Curve

AbstractA combined method was developed to forecast the spatial and the temporal probability of occurrence of rainfall-induced shallow landslides over large areas. The method also allowed to estimate the dynamic change of this probability during a rainfall event. The model, developed through a data-driven approach basing on Multivariate Adaptive Regression Splines technique, was based on a joint probability between the spatial probability of occurrence (susceptibility) and the temporal one. The former was estimated on the basis of geological, geomorphological, and hydrological predictors. The latter was assessed considering short-term cumulative rainfall, antecedent rainfall, soil hydrological conditions, expressed as soil saturation degree, and bedrock geology. The predictive capability of the methodology was tested for past triggering events of shallow landslides occurred in representative catchments of Oltrepò Pavese, in northern Italian Apennines. The method provided excellently to outstanding performance for both the really unstable hillslopes (area under ROC curve until 0.92, true positives until 98.8%, true negatives higher than 80%) and the identification of the triggering time (area under ROC curve of 0.98, true positives of 96.2%, true negatives of 94.6%). The developed methodology allowed us to obtain feasible results using satellite-based rainfall products and data acquired by field rain gauges. Advantages and weak points of the method, in comparison also with traditional approaches for the forecast of shallow landslides, were also provided.

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Spatio-temporal Analysis of Hydrological Drought at Catchment Scale Using a Spatially-distributed Hydrological Model

Procedia Engineering ◽

10.1016/j.proeng.2016.07.577 ◽

2016 ◽

Vol 154 ◽

pp. 738-744 ◽

Cited By ~ 5

Author(s):

Vitali Diaz Mercado ◽

Gerald Corzo Perez ◽

Dimitri Solomatine ◽

Henny A.J. van Lanen

Keyword(s):

Hydrological Model ◽

Temporal Analysis ◽

Hydrological Drought ◽

Distributed Hydrological Model ◽

Catchment Scale ◽

Spatially Distributed ◽

Spatio Temporal

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THE EFFECT OF GROUNDWATER ON SOIL FORMATION IN A MORAINAL LANDSCAPE IN SASKATCHEWAN

Canadian Journal of Soil Science ◽

10.4141/cjss85-033 ◽

1985 ◽

Vol 65 (2) ◽

pp. 293-307 ◽

Cited By ~ 71

Author(s):

J. J. MILLER ◽

D. F. ACTON ◽

R. J. ST. ARNAUD

Keyword(s):

Groundwater Flow ◽

Water Table ◽

Soil Formation ◽

Lateral Flow ◽

Dominant Factor ◽

Slope Position ◽

Soluble Salts ◽

Runoff Water ◽

Depth To Water Table ◽

Water Tables

The results of this study indicate the importance of groundwater flow and water table depth on the genesis, characteristics and distribution of soils within a hummocky morainal landscape. Non-saline and non-carbonated soils in upland depressions can be attributed to "depression-focused" recharge by snowmelt and snowmelt runoff in the spring, as evidenced by deep sola and/or eluvial horizons. Non-saline and carbonated soils on lower slopes adjacent to depressions are associated with local discharge and/or lateral flow from the adjacent groundwater mounds under the depressions in spring, as well as upward flow in the summer resulting from water use by phreatophytes such as willows, creating a water table depression around the slough fringes. Saline and carbonated soils at low elevations are associated with shallow and rather stable water tables, and local discharge from surrounding uplands. Soil types on uplands are more dependent on slope position and infiltration than on depth to water table or groundwater flow. Non-saline soils of different profile types occur on mid- and upper slope positions. These areas have a deep water table with mainly recharge or lateral flow occurring in the saturated zone. The infiltration of surface runoff water in upland depressions is the dominant factor influencing the distribution of soluble salts in this hummocky landscape. Key words: Water table, landscape position, recharge, discharge, soluble salts, soil genesis, morphology, carbonate soil

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Evaluating the performance of streamflow simulated by an eco-hydrological model calibrated and validated with global land surface actual evapotranspiration from remote sensing at a catchment scale in West Africa

Journal of Hydrology Regional Studies ◽

10.1016/j.ejrh.2021.100893 ◽

2021 ◽

Vol 37 ◽

pp. 100893

Author(s):

Abolanle E. Odusanya ◽

Karsten Schulz ◽

Eliezer I. Biao ◽

Berenger A.S. Degan ◽

Bano Mehdi-Schulz

Keyword(s):

Remote Sensing ◽

West Africa ◽

Land Surface ◽

Hydrological Model ◽

Actual Evapotranspiration ◽

Catchment Scale ◽

Global Land

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Large-scale lateral saturated soil hydraulic conductivity as metric for the connectivity of the subsurface flow paths at hillslope scale

10.22541/au.163896913.32177523/v1 ◽

2021 ◽

Author(s):

Mario Pirastru ◽

Massimo Iovino ◽

Hassan Awada ◽

Roberto Marrosu ◽

Simone Di Prima ◽

...

Keyword(s):

Soil Moisture ◽

Hydraulic Conductivity ◽

Spatial Scale ◽

Water Table ◽

Subsurface Flow ◽

Lateral Flow ◽

Saturated Soil ◽

Flow Paths ◽

Soil Hydraulic Conductivity ◽

Hillslope Scale

Lateral saturated soil hydraulic conductivity, Ks,l, is the soil property governing subsurface water transfer in hillslopes, and the key parameter in many numerical models simulating hydrological processes both at the hillslope and catchment scales. Likewise, the hydrological connectivity of lateral flow paths plays a significant role in determining the intensity of the subsurface flow at various spatial scales. The objective of the study is to investigate the relationship between Ks,l and hydraulic connectivity at the hillslope spatial scale. Ks,l was determined by the subsurface flow rates intercepted by drains, and by water table depths observed in a well network. Hydraulic connectivity of the lateral flow paths was evaluated by the synchronicity among piezometric peaks, and between the latter and the peaks of drained flow. Soil moisture and precipitation data were used to investigate the influence of the transient hydrological soil condition on connectivity and Ks,l. It was found that the higher was the synchronicity of the water table response between wells, the lower was the time lag between the peaks of water levels and those of the drained subsurface flow. Moreover, the most synchronic water table rises determined the highest drainage rates. The relationships between Ks,l and water table depths were highly non-linear, with a sharp increase of the values for water table levels close to the soil surface. Estimated Ks,l values for the full saturated soil were in the order of thousands of mm h-1, suggesting the activation of macropores in the root zone. The Ks,l values determined at the peak of the drainage events were correlated with the indicators of synchronicity. The sum of the antecedent soil moisture and of the precipitation was correlated with the indicators of connectivity and with Ks,l. We suggest that, for simulating realistic processes at the hillslope scale, the hydraulic connectivity could be implicitly considered in hydrological modelling through an evaluation of Ks,l at the same spatial scale.

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Development and application of a soil classification-based conceptual catchment-scale hydrological model

Journal of Hydrology ◽

10.1016/j.jhydrol.2005.02.018 ◽

2005 ◽

Vol 312 (1-4) ◽

pp. 277-293 ◽

Cited By ~ 24

Author(s):

D. Maréchal ◽

I.P. Holman

Keyword(s):

Hydrological Model ◽

Soil Classification ◽

Catchment Scale

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Assessment of catchment response and calibration of a hydrological model using high-frequency discharge–nitrate concentration data

Hydrology Research ◽

10.2166/nh.2013.087 ◽

2013 ◽

Vol 44 (6) ◽

pp. 995-1012 ◽

Cited By ~ 13

Author(s):

Rajesh R. Shrestha ◽

Karsten Osenbrück ◽

Michael Rode

Keyword(s):

Surface Runoff ◽

High Frequency ◽

Hydrological Model ◽

Nitrate Concentration ◽

Subsurface Flow ◽

Nitrate Transport ◽

Response Analysis ◽

Catchment Scale ◽

Concentration Data ◽

High Frequency Discharge

This study uses a high-frequency discharge and nitrate concentration dataset from the Weida catchment in Germany for the catchment scale hydrologic response analysis. Nitrate transport in the catchment is mostly conservative as indicated by the nitrate stable isotope (δ15N and δ18O) analysis. Discharge–nitrate concentration data from the catchment show distinctive patterns, suggesting flushing and dilution response. A self-organizing feature map-based methodology was employed to identify such patterns or cluster in the datasets. Based on knowledge of the catchment conditions and prevailing understanding of discharge–nitrate concentration relationship, the clusters were characterized into five qualitative flow responses: (1) baseflow; (2) subsurface flow increase; (3) surface runoff increase; (4) surface runoff recession; and (5) subsurface flow decrease. Such qualitative flowpaths were used as soft data for a multi-objective calibration of a hydrological model (WaSiM-ETH). The calibration led to a reasonable simulation of overall discharge (Nash–Sutcliffe coefficient: 0.84) and qualitative flowpaths (76% agreement). A prerequisite for using such methodology is limited biogeochemical transformation of nitrate (such as denitrification).

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