Micro-characteristics of soil aggregate breakdown under raindrop action

Li, Guanglu; Fu, Yu; Li, Bai-qiao; Zheng, Tenghui; Wu, Faqi; Peng, Gang; Xiao, Tiqiao

doi:10.1016/j.catena.2017.10.027

Cited by 37 publications

(25 citation statements)

References 42 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Lee, Gantzer, Thompson, Anderson, and Ketcham (2008) used high-resolution CT to characterize the development of seals over time, and the results showed that the cumulative porosity varied with the soil depth. Li et al (2018) investigated the relationship between raindrop diameter and aggregate fragmentation from a microscopic perspective via SR-μCT and analyzed the microscopic morphologic characteristics of soil aggregates before and after raindrop impact. Although many researchers have conducted extensive research on soil aggregates during water erosion (Amézketa, Singer, & Le Bissonnais, 1996;Le Bissonnais, 2010;Legout et al, 2005;Fu et al, 2016Fu et al, , 2019, they have mainly investigated the particle size distribution characteristics of split aggregates after splash erosion from a macroscopic perspective.…”

Section: Core Ideasmentioning

confidence: 99%

“…Three raindrop diameters, namely 2.67 mm (small raindrops), 3.39 mm (medium raindrops), and 4.05 mm (large raindrops), were used here to simulate the cases of extreme rainfall. The rainfall intensities of the three raindrops were 5.76, 68.61, and 217.26 mm h −1 , corresponding to light rain, moderate rain, and heavy rain, F I G U R E 1 Photograph of the rainfall simulator (reproduced from Li et al, 2018) respectively. The raindrop diameter was determined by the single raindrop method: 100 consecutive drops from a test needle under the test hydraulic head were measured to calculate the mass and volume of a single drop.…”

Section: Rainfall Testmentioning

confidence: 99%

See 1 more Smart Citation

Microcharacteristics of soil pores after raindrop action

Yang

et al. 2020

Soil Science Soc of Amer J

Self Cite

View full text Add to dashboard Cite

Aggregate breakdown and transportation caused by raindrops clogs soil pores and aggravates the formation of surface crusts. However, changes in soil pore microcharacteristics after raindrop impact are equivocal. In this research, we used synchrotron-based X-ray microcomputed tomography (SR-μCT) and image processing techniques to quantitatively analyze the pore microcharacteristics of undisturbed soil and disturbed soil impacted by raindrop diameters of 2.67 mm (small), 3.39 mm (medium), and 4.05 mm (large). The results showed that the changes in the soil pore microcharacteristics were mainly caused by medium and large raindrops. Compared with the undisturbed soil, the total imaged porosity decreased by 5.91% after splashing by small raindrops and significantly (P < .05) decreased by 15.83 and 18.28% after medium and large raindrop splashing, respectively. The total volume of pores and the porosity of the large pores had the same decreasing trend as the total porosity. The porosity of the elongated pores decreased by 11.51 and 23.41% after medium and large raindrop splashing, respectively. The raindrop action clogged the soil pores. The clogging ratios caused by small, medium, and large raindrops were 1.06, 2.83, and 3.29%, respectively, and increased with raindrop diameter, rain intensity, and rainfall energy. Thus the increase in pore clogging and the decrease in macroporosity are the main reasons for the formation of surface crusts.

show abstract

Section: Core Ideasmentioning

confidence: 99%

Section: Rainfall Testmentioning

confidence: 99%

Microcharacteristics of soil pores after raindrop action

Yang

et al. 2020

Soil Science Soc of Amer J

Self Cite

View full text Add to dashboard Cite

show abstract

“…Equation (2) was used to calculate the raindrop velocity under this test condition [31]. The raindrop energy was calculated by Equation (3). Therefore, the final raindrop energy levels were 2.41 × 10 −5 , 3.68 × 10 −5 , 5.15 × 10 −5 , 7.30 × 10 −5 , 8.97 × 10 −5 , and 22.4 × 10 −5 J m −2 s −1 , which conformed to the range of natural rainfall raindrop energy.…”

Section: Experimental Designmentioning

confidence: 99%

“…Water erosion is the main type of soil erosion in the Loess Plateau. The aggregates caused by splash erosion are dispersed and broken, which is the initial stage of water erosion [1][2][3][4]. Raindrops fall from the air and impact the surface soil particles at a certain speed under the action of gravity.…”

Section: Introductionmentioning

confidence: 99%

Raindrop Energy Impact on the Distribution Characteristics of Splash Aggregates of Cultivated Dark Loessial Cores

Wang

et al. 2019

Water

Self Cite

View full text Add to dashboard Cite

To determine the effect of different rainfall energy levels on the breakdown of soil aggregates, this study analyzed the soil splash erosion amounts and the distribution of particle sizes under six rainfall conditions (rainfall energy: 2.41 × 10−5–22.4 × 10−5 J m−2 s−1 and 1.29 × 10−4 J m−2 s−1) at five splash distances (from 0–10 cm to 40–50 cm). Cores of the size 10 × 20 cm of undisturbed cultivated dark loessial soil were selected in tree replicates as the research subject. The results indicated that splashed aggregates were distributed mainly at splash distances of 0–20 cm, which accounted for 66%–90% of the total splash erosion amount. The splash erosion amount significantly decreased exponentially with increasing splash distance for the same rainfall energy (p < 0.01). The splash erosion amount significantly increased in the power function relationship with increasing rainfall energy at the same splash distance (p < 0.05). A model was obtained to predict the splash erosion amount for rainfall energy and splash distance. The fractal dimension (D) of the aggregates showed a downward opening parabolic relationship with raindrop energy. The maximal value of the rainfall energy was 1.286 × 10−4 J m−2 s−1, which broke the aggregates to the largest degree. Enrichment ratio (ER) values for fragments >2 mm were close to 0. A particle size of 0.25 mm was the critical particle level for splash erosion.

show abstract

“…Soil covering by the pasture is important because it provides protection against the impact of raindrops and cattle trampling, avoiding superficial sealing (Li et al, 2018) and compaction (Silva et al, 2003), respectively. Additionally, vegetation cover increases soil surface roughness (Rocha Júnior et al, 2016) and expresses root density.…”

Section: Ndvi Nir Red Nir Redmentioning

confidence: 99%

Mapping and characterization of intensity in land use by pasture using remote sensing

Calegario

Pereira

et al. 2019

Rev. bras. eng. agríc. ambient.

View full text Add to dashboard Cite

The current demand for food has been met through the exploitation of natural reserves. Brazil has 26% of its extension occupied by agricultural uses, 62% of which are pastures. Degraded pastures have greater land use intensity than well-managed pastures, leading to greater degradation of the environment. Land use classification systems consider that pastures are well managed, a misconception for the Brazilian reality. Based on this approach, it was aimed to develop a methodology for mapping the intensity of land use by pasture via remote sensing. The method of mapping was developed and validated in basins with different soil and climatic characteristics. Three calibrations were performed based on NDVI values to ascertain the influence on the results, being evaluated from the field campaigns and the kappa and weighted kappa indices. The kappa and weighted kappa indices presented reasonable and moderate agreement, respectively. The results were considered as satisfactory for the three calibrations, evidencing that the degree of degradation of the pastures can be estimated in a simple way by remote sensing. The Limoeiro River Basin has around 46.9% of pastures, at least, heavily degraded and 96.6% with some degree of degradation, which contributes to degradation of the natural resources and reduction of livestock farming and economic potential of the basin.

show abstract

Micro-characteristics of soil aggregate breakdown under raindrop action

Cited by 37 publications

References 42 publications

Microcharacteristics of soil pores after raindrop action

Microcharacteristics of soil pores after raindrop action

Raindrop Energy Impact on the Distribution Characteristics of Splash Aggregates of Cultivated Dark Loessial Cores

Mapping and characterization of intensity in land use by pasture using remote sensing

Contact Info

Product

Resources

About