Modified MMF (Morgan–Morgan–Finney) model for evaluating effects of crops and vegetation cover on soil erosion

Abstract

Modifications are made to the revised Morgan-Morgan-Finney erosion prediction model to enable the effects of vegetation cover to be expressed through measurable plant parameters. Given the potential role of vegetation in controlling water pollution by trapping clay particles in the landscape, changes are also made to the way the model deals with sediment deposition and to allow the model to incorporate particle-size selectivity in the processes of erosion, transport and deposition. Vegetation effects are described in relation to percentage canopy cover, percentage ground cover, plant height, effective hydrological depth, density of plant stems and stem diameter. Deposition is modelled through a particle fall number, which takes account of particle settling velocity, flow velocity, flow depth and slope length.

Daily Based Morgan–Morgan–Finney (DMMF) Model: A Spatially Distributed Conceptual Soil Erosion Model to Simulate Complex Soil Surface Configurations

“…The guide values for detachability of clay, silt, and sand are 0.1, 0.5, and 0.3, respectively [27] but these values should be used carefully according to the soil characteristics of study sites as shown in Poesen [46] and it is recommended that users employ field-measured values.…”

“…The guide values for detachability of clay, silt, and sand are 1.0, 1.6, and 1.5, respectively [27]. The values should be used carefully and can be replaced with observed site specific data.…”

“…For cultivated land with tillage, the Manning's roughness coefficient can be derived empirically from the soil surface roughness (RFR; cm m −1 ) as below [27], ln(n) = −2.1132…”

Estimation of Geomorphic Threshold in Permanent Gullies of Lateritic Terrain in Birbhum, West Bengal, India

“…We have applied the revised Morgan Morgan Finney model (RMMF) to estimate annual overland flow and its annual detachment rate and transport capacity [36][37][38] . The critical values of parameter are collected from table values of RMMF model 37 .…”

“…The performance of the model is validated by the value of efficiency coefficient (EC) 40 and is applied successfully in the soil erosion research 38,41 .…”