The role of vegetation on gully erosion stabilization at a severely degraded landscape: A case study from Calhoun Experimental Critical Zone Observatory

Abstract Gully erosion was evidence of land degradation in the southern Piedmont, site of the Calhoun Critical Zone Observatory (CCZO), during the cotton farming era. Understanding of the underlying gully erosion processes is essential to develop gully erosion models that could be useful in assessing the effectiveness of remedial and soil erosion control measures such as gully backfilling, revegetation, and terracing. Development and validation of process-based gully erosion models is difficult because observations of the formation and progression of gullies are limited. In this study, analytic formulations of the two dominant gullying processes, namely, plunge pool erosion and slab failure, are utilized to simulate the gullying processes in the 4-km2 Holcombe's Branch watershed. In order to calibrate parameters of the gully erosion model, gully features (e.g., depth and area) extracted from a high-resolution LiDAR map are used. After the calibration, the gully model is able to delineate the spatial extent of gullies whose statistics are in close agreement with the gullies extracted from the LiDAR DEM. Several simulations with the calibrated model are explored to evaluate the effectiveness of various gully remedial measures, such as backfilling and revegetation. The results show that in the short-term, the reshaping of the topographical surface by backfilling and compacting gullies is effective in slowing down the growth of gullies (e.g., backfilling decreased the spatial extent of gullies by 21–46% and decreased the average depth of gullies by up to 9%). Revegetation, however, is a more effective approach to stabilizing gullies that would otherwise expand if no gully remedial measures are implemented. Analyses of our simulations show that the gully stabilization effect of revegetation varies over a wide range, i.e., leading to 23–69% reduction of the spatial extent of gullies and up to 45% reduction in the depth of gullies, depending on the selection of plant species and management practices.

[1]  J. Poesen,et al.  Predicting soil erosion and sediment yield at the basin scale: Scale issues and semi-quantitative models , 2005 .

[2]  Gian Battista Bischetti,et al.  Root Strength and Root Area Ratio of Forest Species in Lombardy (Northern Italy) , 2005, Plant and Soil.

[3]  G. R. Foster,et al.  A Process-Based Soil Erosion Model for USDA-Water Erosion Prediction Project Technology , 1989 .

[4]  Flores Cervantes,et al.  Headcut retreat resulting from plunge pool erosion in a 3D landscape evolution model , 2004 .

[5]  Bruce Abernethy,et al.  The distribution and strength of riparian tree roots in relation to riverbank reinforcement , 2001 .

[6]  J. Poesen,et al.  Gully erosion and environmental change: importance and research needs , 2003 .

[7]  R. Bras,et al.  Integration of fuzzy logic and image analysis for the detection of gullies in the Calhoun Critical Zone Observatory using airborne LiDAR data , 2015 .

[8]  C. R. Jackson,et al.  Prescribed burning effects on the hydrologic behavior of gullies in the South Carolina Piedmont , 2007 .

[9]  David R. Easterling,et al.  Regional surface climate conditions in CMIP3 and CMIP5 for the United States : differences, similarities, and implications for the U.S. National Climate Assessment , 2015 .

[10]  Andrew D. Weiss.  Topographic position and landforms analysis , 2001 .

[11]  Zhou Shi,et al.  Assimilating satellite imagery and visible-near infrared spectroscopy to model and map soil loss by water erosion in Australia , 2016, Environ. Model. Softw..

[12]  M. Kazda,et al.  Clustered Distribution of Tree Roots and Soil Water Exploitation , 2009 .

[13]  Daniel Markewitz,et al.  Understanding Soil Change—Soil Sustainability over Millennia, Centuries, and Decades , 2001 .

[14]  Anthony J. Jakeman,et al.  A review of erosion and sediment transport models , 2003, Environ. Model. Softw..

[15]  Enrique R. Vivoni,et al.  Ecohydrologic role of solar radiation on landscape evolution , 2015 .

[16]  J W Harden,et al.  The Impact of Agricultural Soil Erosion on the Global Carbon Cycle , 2007, Science.

[17]  Torsten Schaub,et al.  The variability of root cohesion as an influence on shallow landslide susceptibility in the Oregon Coast Range , 2001 .

[18]  J. Poesen,et al.  The effectiveness of loose rock check dams for gully control in Tigray, northern Ethiopia , 2004 .

[19]  J. Poesen,et al.  Gully erosion: Impacts, factors and control , 2005 .

[20]  R. Bras,et al.  Modeling the hydrological and mechanical effect of roots on shallow landslides , 2016, Water Resources Research.

[21]  Dongkyun Kim,et al.  Regionalization of the Modified Bartlett-Lewis Rectangular Pulse Stochastic Rainfall Model , 2013 .

[22]  S. Trimble,et al.  Man-induced soil erosion on the Southern Piedmont, 1700-1970. , 2008 .

[23]  S. Bennett.  Effect of slope on the growth and migration of headcuts in rills , 1999 .

[24]  B. Peucker‐Ehrenbrink,et al.  Global carbon export from the terrestrial biosphere controlled by erosion , 2015, Nature.

[25]  L. D. Norton,et al.  Soil erosion by surface water flow on a stony, semiarid hillslope , 1999 .

[26]  Jean Poesen,et al.  Assessment of sidewall erosion in large gullies using multi-temporal DEMs and logistic regression analysis , 2004 .

[27]  J. Brice.  Erosion and deposition in the loess-mantled Great Plains, Medicine Creek drainage basin, Nebraska , 1966 .

[28]  Gregory E. Tucker,et al.  A stochastic approach to modeling the role of rainfall variability in drainage basin evolution , 2000 .

[29]  Stephen E. Darby,et al.  Numerical Simulation of Widening and Bed Deformation of Straight Sand-Bed Rivers. II: Model Evaluation , 1996 .

[30]  R. Bras,et al.  Vegetation-modulated landscape evolution: Effects of vegetation on landscape processes, drainage density, and topography , 2004 .

[31]  Joseph. Wood,et al.  The geomorphological characterisation of Digital Elevation Models , 1996 .

[32]  N. Trustrum,et al.  Gully erosion and sediment production: Te Weraroa Stream, New Zealand , 2003 .

[33]  P. Waylen,et al.  Beyond Precipitation: Physiographic Gradients Dictate the Relative Importance of Environmental Drivers on Savanna Vegetation , 2013, PloS one.

[34]  G. Vosselman.  SLOPE BASED FILTERING OF LASER ALTIMETRY DATA , 2000 .

[35]  Resistance to shallow landslide failure through root-derived cohesion in east coast hill country soils, North Island, New Zealand , 1999 .

[36]  Otto R. Stein,et al.  IMPINGING JET CALIBRATION OF EXCESS SHEAR SEDIMENT DETACHMENT PARAMETERS , 1997 .

[37]  R. Bras,et al.  Modeling the effects of vegetation‐erosion coupling on landscape evolution , 2004 .

[38]  J. Poesen,et al.  How fast do gully headcuts retreat , 2016 .

[39]  Ronald L. Bingner,et al.  An empirical investigation of gully widening rates in upland concentrated flows , 2013 .

[40]  M. J. Chadwick,et al.  Bioengineering for Land Reclamation and Conservation , 1980 .

[41]  Quan J. Wang,et al.  Improving statistical forecasts of seasonal streamflows using hydrological model output , 2012 .

[42]  A. Stokes,et al.  Using three-dimensional plant root architecture in models of shallow-slope stability. , 2007, Annals of botany.

[43]  L. Band,et al.  Topographic and ecologic controls on root reinforcement , 2009 .

[44]  Gregory E. Tucker,et al.  Implications of bank failures and fluvial erosion for gully development: Field observations and modeling , 2005 .

[45]  Robert R. Wells,et al.  Morphodynamics of headcut development and soil erosion in upland concentrated flows. , 2009 .

[46]  D. Kretschmann,et al.  The Mechanical Properties of Wood , 1915 .

[47]  G. R. Foster,et al.  WEPP: A new generation of erosion prediction technology , 1991 .

[48]  O. Stein,et al.  Experiments and modeling of head cut migration in stratified soils , 2002 .

[49]  Andreas Gericke,et al.  Improving the estimation of erosion-related suspended solid yields in mountainous, non-alpine river catchments , 2012, Environ. Model. Softw..

[50]  D. Mackenzie,et al.  Sediment yields and turbidity records from small upland subcatchments in the Warragamba Dam Catchment, southern New South Wales , 2002 .

[51]  W. H. Wischmeier,et al.  Predicting rainfall erosion losses : a guide to conservation planning , 1978 .

[52]  Leonardo Noto,et al.  tRIBS-Erosion: A parsimonious physically-based model for studying catchment hydro-geomorphic response , 2012 .

[53]  Peter S. Eagleson,et al.  Climate, soil, and vegetation: 1. Introduction to water balance dynamics , 1978 .

[54]  R. Bras,et al.  Development of gullies on the landscape: A model of headcut retreat resulting from plunge pool erosion , 2006 .