Runoff and soil loss under individual plants of a semi‐arid Mediterranean shrubland: influence of plant morphology and rainfall intensity

Abstract

The influence of plant morphology and rainfall intensity on soil loss and runoff was determined at the plant scale for three representative species of a semi-arid patchy shrubland vegetation of east Spain, representing contrasting canopy structures and plant phenologies (Rosmarinus officinalis, Anthyllis cytisoides and Stipa tenacissima).Twenty-seven microplots of less than 1 m 2 , each containing one single plant, were built to quantify runoff volume and sediment yield under the canopies of the three species. Runoff and rates of soil loss measured in these plots under natural rainfall conditions were compared with control microplots built in the bare inter-plant areas. Precipitation was automatically recorded and rainfall intensity calculated over a two-year period.Results indicated that individual plants played a relevant role in interrill erosion control at the microscale. Compared with a bare soil surface, rates of soil loss and runoff reduction varied strongly depending on the species. Cumulative soil loss was reduced by 94·3, 88·0 and 30·2 per cent, and cumulative runoff volume was reduced by 66·4, 50·8 and 18·4 per cent under the Rosmarinus, Stipa and Anthyllis canopies, respectively, compared with a bare surface. Anthyllis was significantly less efficient than the two other species in reducing runoff volume under its canopy. Differences between species could only be identified above a rainfall intensity threshold of 20 mm h − − − − −1 . The different plant morphologies and plant components explained the different erosive responses of the three species. Canopy cover played a major role in runoff and soil loss reduction. The presence of a second layer of protection at the soil surface (litter cover) was fundamental for erosion control during intense rainfall. Rainfall intensity and soil water status prior to rainfall strongly influenced runoff and soil loss rates. The possible use of these species in restoration programmes of degraded areas is discussed.

Influence of three plant species with different morphologies on water runoff and soil loss in a dry-warm river valley, SW China

“…5 and 6). Similar to the study by Bochet et al (2006), this study also found that different species had varied effectiveness (Figs. 4-6).…”

“…However, few were conducted at individual plant scale (De Baets et al, 2007), on which we could relate such effects to plant morphology and thereby provide necessary information to select suitable plant species in terms of plant morphology for vegetation restoration in arid and semiarid environments. Moreover, the existing studies at individual scale were mainly concentrated in Mediterranean landscapes (Bochet et al, 1998(Bochet et al, , 2006Casermeiro et al, 2004). In these studies of individual plant scale, small runoff plots (<1 m 2 ) was often used to monitor runoff and soil loss.…”

The fate of seeds in the soil: a review of the influence of overland flow on seed removal and its consequences for the vegetation of arid and semiarid patchy ecosystems

“…Under these conditions, seeds in the seed bank or resting on the soil surface after primary dispersal are exposed to overland flow, especially in bare patches where high rates of runoff and sediment transport have been reported (Cerdà, 1997;Calvo-Cases et al, 2003;Boix-Fayos et al, 2005;Bochet et al, 2006). The first evidence that runoff may act as a vector of seed transport was indirect and based on observations of seed dispersal strategies in runoff-prone areas (Friedman and Orshan, 1975;Friedman and Stein, 1980), comparisons of plant distribution with different dispersal mechanisms between slopes and wadis (Reichman, 1984), or descriptions of seed distribution patterns in different microhabitats (Ellner and Schmida, 1981) in desert ecosystems worldwide.…”

Runoff formation from experimental plot, field, to small catchment scales in agricultural North Huaihe River Plain, China

“…Surface runoff occurrence is more frequent with crops at the seedling or early growth stage than later in the season (Bochet et al, 2006;Jiao et al, 2010). In the study area, soybean and corn are seeded, whereas cotton is transplanted in midJune.…”