Soil Deposition Rates Research Articles

Effects of soil erosion–deposition on corn yields in the Chinese Mollisol region

Soil erosion is a major challenge for crop production maintenance and improvement in agricultural regions worldwide. However, quantifying the impacts of soil erosion rate on crop yield has not been carried out often, and there are few reports on impacts of soil deposition crop yields, especially in the Chinese Mollisol Region. Thus, this study quantified soil erosion–deposition rates (SEDRs) at three agricultural catchments in the Chinese Mollisol region using the 137Cs technique and assessed soil erosion–deposition impacts on corn (Zea mays L.) yield. The results showed that SEDRs varied from −5471.7 (deposition) to 9956.0 (erosion) t km−2 yr−1. The distributions of both soil erosion and deposition in the three catchments were in coexistence, but soil erosion was dominant. In addition, above 2500 t km−2 yr−1 of soil erosion rates (larger than slight erosion rates) in the three catchments accounted for 41.0 %, indicating that soil erosion was severe. Moreover, corn yields in the three catchments ranged from 1.9 to 14.6 t ha−1. Compared with deposited sites, corn yields in eroded sites were 19.2 %–40.6 % lower. Furthermore, when soil erosion rates were moderate (2500–5000 t km−2 yr−1), corn yields were 32.4 % lower than those in non-eroded sites. The spatial distribution of corn yield was opposite to that of soil erosion rate at catchment and slope scales. The relationship between corn yields and soil erosion rates had a negative linear relationship (p < 0.01), which was validated with acceptable accuracy. There was a positive linear relationship between corn yields and soil deposition rates without statistical significance (p > 0.05). These findings are valuable for assessing how soil erosion–deposition affects crop yields to implement countermeasures for controlling soil erosion and maintaining sustainable agricultural development.

Using Cs-137 measurements and RUSLE model to explore the effect of land use changes on soil erosion and deposition rates in a mid-sized catchment in southern Italy

In some areas of southern Italy, the change in land use over the last 4–5 decades has increased pressure on land and water resources and caused different forms of soil degradation. In order to mitigate the magnitude of soil erosion, different strategies that include construction of flood control structures and reforestation programs have been done in several areas. However, quantifying the effectiveness of these strategies is difficult in absence of direct measurements of soil erosion. To cover this information gap, the use of distributed numerical models coupled with measurements of the radionuclide cesium-137 (137Cs) offers a good alternative to the classic experimental sites (plot, catchments) that, on the contrary, require long term datasets to produce reliable estimates of soil loss. In this paper, measurements of 137Cs in a floodplain area are firstly described for a representative Calabrian catchment as an example to reconstruct the trend of soil deposition rates during the last six decades. These measurements have been integrated with estimates of soil loss obtained with the Revised Universal Soil Loss Equation (RUSLE) model for which land use maps of different periods are available. The final comparison between estimates of soil erosion provided by the RUSLE at catchment scale and sedimentation rates derived from 137Cs measurements on depositional areas allowed interesting information on the trend of soil erosion and deposition rates in these areas to be obtained.

Contrasting soil dynamics in a formerly glaciated and non-glaciated Mediterranean mountain plateau (Serra da Estrela, Portugal)

Few data are available on how soil erosion rates compare between surfaces of different ages because short-term processes often overprint the longer-term erosion signal. This study investigated the soil dynamics among two end-member sites, a formerly glaciated ('young', maximum glacial extent at 22–30 ka BP) and a non-glaciated ('old') area at the Serra da Estrela (Portugal). To disentangle soil distribution rates over different timeframes, isotopes for long-term (10Be), mid-term (δ13C) and short-term (239+240Pu) periods were applied together with principles of the percolation theory.The formerly glaciated area has soils with a lower degree of weathering and lower carbon content compared to soils of the ‘old‘, non-glaciated area. The selected isotopes and their distribution along the soil profiles revealed temporal differences in soil mixing process. It is hypothesised that the slightly higher elevation and formerly glaciated sites experienced cryoturbation effects over a longer period, while being less active or absent for the last few decades at the older, non-glaciated soils.The average long-term (millennia) soil erosion rates correspond to the expected higher rates at the younger surface and lower rates at the older surface. Once the formerly glaciated area became ice-free, soil erosion rates were high and decreased giving rise to average long-term rates of 101–140 [t km−2 yr−1] for the older surfaces and 176–248 [t km−2 yr−1] for the younger surfaces. In addition, seasonal freeze–thaw of the soils has persisted over a long period and affected the younger soils more intensively than the older soils. The current (last decades) soil redistribution rates, however, are up to one order of magnitude higher than the millennia rates and are controlled by surface angle and vegetation cover and less by soil texture. The more undulated, non-glaciated older surface had the highest short-term (decades) soil erosion rates in the range of 900–1700 [t km−2 yr−1], exhibits degrading conditions and relatively shallow soils. The younger soils, however, showed short-term (last few decades) average soil deposition rates of ∼ 230 [t km−2 yr−1]. Human impact (bush fires, grazing) is the cause for the currently strong soil degradation at the non-glaciated area.

A characterization study for the properties of dust particles collected on photovoltaic (PV) panels in Sharjah, United Arab Emirates

Dust accumulation on photovoltaic (PV) modules is responsible for the reduction in solar radiation received and/or transmitted, hence, decreases the efficiency of the PV cells. To enhance the performance of PV modules, the nature and the structure of dust should be evaluated. This paper investigates the seasonal variability of dust and PV soiling losses over 4 months (15 weeks, over the summer of 2018) in a soiling station deployed at the American University of Sharjah, UAE. A custom-made setup was employed to collect the dust samples on glass sheets. This will provide a better understanding of the soil deposition rates and composition. The accumulated dust was characterized for its morphological and elemental properties. The dust samples were directly collected from the panels mounted outdoor in the desert environment. Various characterization techniques were performed to determine the dust samples’ composition. The results showed that the dust particles are mostly rich in carbon, oxygen, calcium, silicon, thus indicating the presence of silica and calcite. UV–Vis results showed a decrease in transmittance of 30% after 15 weeks of soiling. This results of this work are essential for the development of proper self-cleaning techniques for PV modules deployed in Sharjah.

Soil erosion and corn yield in a cultivated catchment of the Chinese Mollisol region.

Evaluation of soil redistribution rates and influence on crop yield in agricultural catchments is very important information, which can provide a scientific basis for arrangement of soil and water conservation measures and sustainable crop production. In recent decades, the soil erosion has greatly aggravated in the Mollisol region of Northeast China due to unreasonable land management, which in turn has reduced crop yield. The objectives of this study were to investigate the spatial distribution of soil redistribution and the relationship between crop yield and soil redistribute at a catchment of the Chinese Mollisol region. A total of 176 soil samples were collected based on a 200 m by 200 m grid and 4 yr of corn (Zea mays L.) yields were measured. The 137Cs trace technique and Zhang Xinbao’s mass balance model indicated that the soil redistribution rates ranged from −7122.25 to 5471.70 t km−2 yr−1 and averaged −830.10 t km−2 yr−1. Soil erosion dominated in the research area. The corn yields for four years ranged from 43.24 to 136.19 kg km−2 and averaged 90.42 kg km−2. The spatial distribution of soil redistribution rates and corn yield showed a similar ribbon and plaque characteristics at the catchment. An equation between corn yield and soil redistribution rates was fitted and showed that there was a significant negative correlation between corn yield and soil erosion rates, while there was no relationship between the corn yield and soil deposition rates. Therefore, effective soil and water conservation measures are urgently needed to increase crop yield and realize sustainable land-use management.

Short-range variation in a Wisconsin soilscape (USA)

Here we report on the variation of a soilscape in south central Wisconsin, USA. The variation in soil properties and soil features results in four soil order (Entisols, Inceptisols, Alfisols and Mollisols). Observations were made along a 200 m transect in a field that was cultivated since 1870. Slopes ranged from 7.5% on the back slope to 0% in the lower part. The soilscape had a total relief difference of 7.0 m. The soils were studied by 41 soil pits (60 cm), 6 soil pits (125 cm), 15 soil augers (100 cm), and ground-penetrating radar imagery. The summit and shoulder consist of coarse glacial outwash (loamy sands) over limestone whereas the lower part is lacustrine sediments over coarse outwash (loams, silty loams). The A-horizon thickness ranged from 14 to 52 cm with thick A horizons at the toeslope that also had the lowest soil pH. The soil organic carbon (SOC) contents of the A horizons ranged from 11.6 to 46.9 g C kg–1, and the higher contents are in the lower part of the soilscape. SOC stocks (0–20 cm depth) ranged from 50 to 70 Mg C ha–1 on the summit and backslope, but were 80 to 95 Mg C ha–1 in the flat part of the soilscape. The lowest soybean yields (1.6 Mg ha–1) were found at the summit and the highest yield (6.3 Mg ha–1) at the lower end of the backslope. Soybean yields were correlated to the thickness of the A horizon, and every 10 cm increase in A horizon thickness yielded an extra 0.6 Mg soybeans ha–1. Analysis of spherical magnetic particles was used to estimate soil erosion rates that were highest on the backslope (16.2 Mg ha–1 yr–1) and rates of soil deposition in the lowest part of the soilscape was 18.8 Mg haP1 yr–1. It seems that there is no net soil and SOC loss within this soilscape. All in all, we found 4 soil taxonomic orders within 200 m. The variation in this soilscape was substantial and probably enhanced by 140 years of cultivation.

Combining 137Cs measurements and a spatially distributed erosion model to assess soil redistribution in a hedgerow landscape in northwestern France (1960–2010)

Erosion is one of the main threats to soils and is associated with numerous environmental and economic impacts. At the landscape scale, soil redistribution patterns induced by water and tillage erosion are complex, and landscape structures play an important role in their spatial distribution. In this study, soil redistribution patterns, generated by both water and tillage erosion, were estimated in the vicinity of hedges in an agricultural landscape. Two complementary methods were employed to estimate soil redistribution from 1960 to 2010: 137Cs conversion models and a spatially distributed soil erosion model (LandSoil model). Both methods determined that hedges affected soil redistribution patterns, which led to soil deposition or limited soil erosion uphill from hedges, even though soil erosion rates were consistently higher than soil deposition rates. Depending on the method, mean soil redistribution rates ranged from −15.9 to −4.7tha−1yr−1 for all sampling points, from −4.8 to 2.2tha−1yr−1 in positions uphill from hedges and from −4.8 to −11.2tha−1yr−1 in positions located downhill from hedges. The impact of tillage on soil redistribution in the vicinity of hedges was found to be higher than that of water processes because 87% of net soil redistribution was linked to tillage. This confirmed the importance of including landscape structure and working at the landscape scale rather than at the plot scale to better estimate soil redistribution in agricultural areas.

Data uncertainties in anthropogenic phosphorus flow analysis of lake watershed

Abstract The data uncertainty is a crucial limitation for substance flow analysis (SFA) studies. Monte Carlo (MC) simulation is used to assess the data uncertainty of the anthropogenic phosphorous (P) flow analysis in Chaohu Watershed. The study selects the key data in crop farming, large-scale breeding, and rural consumption subsystems, which are the biggest contributors to P emissions. The results show that in the crop farming subsystem, the P-containing rate of crop, soil deposition rate, harvest of crop, proportion of large-scale livestock excrement to field, and the amount of applied chemical fertilizer are the greatest contributors to the output uncertainty. While the amount of feed consumed per large-scale livestock, amount of large-scale livestock, P-containing rate of feed consumed by large-scale livestock, and proportion of large-scale livestock excrement to field have the greatest uncertainties in the large-scale breeding subsystem. Moreover, in the rural consumption subsystem, both of the P-containing rate of crop and the amount of crop consumed per rural people have the greatest uncertainties. By analyzing the reasons leading to the data uncertainties, the suggestions for minimizing the uncertainty are also proposed. The study also shows that the MC methodology is an efficient tool to solve the data uncertainty in SFA study.

Magnetic susceptibility and Cs-137 inventory variability as influenced by land use change and slope positions in a hilly, semiarid region of west-central Iran

The objective of this study was to explore the slope position and land use change effects on the variability in magnetic susceptibility and 137Cs inventory as the soil redistribution indicators in a hilly semiarid calcareous area in Iran. The selected study area is located in a hilly region with pasture and cultivation land use of Fereydunshahr, Isfahan Province in west-central Iran. In the two mentioned dominant ecosystems, four slope positions including summit, shoulder, backslope and footslope were identified and in each land use and slope position, three cores were selected to collect 72 soil samples from three depths (0–10, 10–20, 20–30 cm) in an area of 15 × 15 cm. Additional 28 soil samples were collected from the reference site for soil loss and deposition calculations by using the Cs-137 measurement. The results of the study with the use of the Cs-137 technique showed that the average soil loss in the pasture land (46.4 t ha− 1 yr− 1) was significantly (p < 0.05) lower than the average soil loss in the cultivated land (80.4 t ha− 1 yr− 1). The highest soil loss in both land uses was obtained in the shoulder position, 60.1 and 84.4 t ha− 1 yr− 1, respectively, for the pasture and cultivated lands. Moreover, the highest rates of soil deposition was observed in a footslope position in both land uses and they were 34 and 32.4 t ha− 1 yr− 1 for the pasture and cultivated lands, respectively. Magnetic susceptibility was significantly (p < 0.05) greater in pasture (χlf = 41.51 × 10− 8 m3/kg) than in the cultivated land (χlf = 34.90 × 10− 8 m3/kg). The pasture land with a lower soil loss rate, indicated significantly higher magnetic susceptibility in all landform positions as compared to that in the cultivated land. The results of the correlation analysis showed that among the studied soil physico-chemical properties, χlf (r = 0.83, p < 0.01) in the pasture land had the highest correlation with the Cs-137 inventory. Throughout the non-linear regression analysis, χlf was introduced for relating soil parameters and the cesium inventory explained 68% and 79% of the total variability of 137Cs in the pasture and cultivated lands, respectively. The results implied that the variability in the magnetic susceptibility within the hillslope is consistent with the variation of the Cs-inventory; and the results thus demonstrate the slope and land use effects on soil redistribution.

Soil C erosion and burial in cropland

AbstractErosion influences the lateral and vertical distribution of soil in agricultural landscapes. A better understanding of the effects of erosion and redistribution on soil organic carbon (C) within croplands would improve our knowledge of how management practices may affect global C dynamics. In this study, the vertical and lateral distribution of soil organic C was characterized to evaluate the amounts and timescales of soil organic C movement, deposition and burial over the last 50 years in different agroecosystems across Canada. There was strong evidence that a substantial portion of eroded sediment and soil organic C was deposited as colluvium close to its source area, thereby burying the original topsoil. The deepest aggraded profile was in a potato field and contained over 70 cm of deposited soil indicating an accumulation rate of 152 Mg ha yr−1; aggraded profiles in other sites had soil deposition rates of 40–90 Mg ha−1 yr−1. The largest stock of soil organic C was 463 Mg ha−1 (to 60 cm depth) and soil C deposition ranged from about 2 to 4 Mg ha−1 yr−1 across all sites. A distinct feature observed in the aggraded profiles at every site was the presence of a large increase in soil organic C concentration near the bottom of the A horizon; the concentration of this C was greater than that at the soil surface. Compared to aggraded profiles, the SOC concentration in eroded profiles did not differ with depth, suggesting that dynamic replacement of soil organic C had occurred in eroded soils. A large amount of soil organic C is buried in depositional areas of Canadian croplands; mineralization of this stock of C appears to have been constrained since burial, but it may be vulnerable to future loss by management practices, land use change and a warming climate.

Soil redistribution rate and its relationship with soil organic carbon and total nitrogen using 137Cs technique in a cultivated complex hillslope in western Iran

The spatial pattern of soil redistribution rate was investigated using cesium-137 ( 137Cs) within a cultivated complex hillslope in western Iran. The relationship between soil redistribution rate and soil organic carbon and total nitrogen pattern were studied using co-regionalization analysis. Ninety-one soil cores were sampled for 137Cs, total nitrogen, and soil organic carbon measurements. The simplified mass balance model estimated a gross erosion rate of 29.8 t ha −1 yr −1 and a net soil deposition rate of 21.8 t ha −1 yr −1; hence, a net soil loss rate of 8 t ha −1 yr −1. This magnitude of soil erosion rate is higher than the acceptable rate in semiarid regions. Co-regionalization analysis and co-dispersive coefficients among the selected variables showed that only a small fraction of the variability in total nitrogen and soil organic carbon could be explained by soil redistribution and that the remaining might be the result of different management practices by local farmers.

Radiocarbon Dating of the Mansuri Paleolithic Site, Cheongwon, Korea

Construction of a new science complex in Osong, Cheongwon-gun, Korea, has allowed the investigation of 14 different Paleolithic localities, excavated during 2005–2007. Here, we investigated localities 1 and 12 of the Mansuri Paleolithic site to obtain chronological information using radiocarbon dating. The soil deposition rates varied from 0.09 to 0.15 mm/yr over the period ranging from 33 to 31 kyr BP for locality 1. Locality 12 samples were more recent, &lt;10 ka, and have similar accumulation rates, averaging 0.11 mm/yr. The soil ages of locality 12 were found to be younger than 10 kyr BP. Results for both soil and organic materials at this locality gave much younger ages at shallower depths than the ages expected by the Korean Paleolithic cultural history for this region. Therefore, these more recent deposits may not be associated with the cultural layers and are interpreted to have been hydrologically modified following emplacement. 14C dates of the soil and organic materials at locality 12 confirm that there is evidence for multiple human occupations throughout the last 9 kyr BP.

Hydrologic and aeolian controls on vegetation patterns in arid landscapes

Hydrological and aeolian processes redistribute sediments and nutrients within arid landscapes with important effects on the composition and structure of vegetation. Despite the relevance of wind and water erosion to the dynamics of arid and semiarid ecosystems, the interactions between these two processes remain poorly understood. In this paper we present the results of an intensive set of infiltration experiments from the Chihuahuan Desert, showing that in this system the infiltration capacity under the shrub canopy is lower than that at the outer edges of the vegetated patches. Hence, runoff is more likely to occur from the middle of these shrub‐dominated areas to the edges. These experimental results show that the differential rates of soil deposition and removal by aeolian processes result in differential rates of hydrological processes such as infiltration and runoff with important implications for the formation and expansion of mesquite dunes in arid landscapes.

Soil erosion rates under intensive vegetable production on clay loam, strongly structured soils at Pukekohe, New Zealand

Rates of soil redistribution by water and tillage erosion were determined in 3 fields under long-term continuous vegetable production on clay loam, strongly structured soils derived from volcanic ash at Pukekohe, South Auckland, New Zealand. Erosion and deposition rates were estimated using a mass balance model to convert variation in 137Cs areal activity within the fields to estimates of erosion and deposition. Caesium-137 areal activity in cropped fields ranged from 171 to 2144 Bq/m2, compared with a reference value under permanent pasture of 774 Bq/m2. There was a characteristic pattern of 137Cs distribution within each field, with differences between the fields related to variation in topography. Lowest values of 137Cs were found in the upper parts of each field and highest values towards the base of each field. In all 3 fields there was a net loss of 137Cs, ranging from 13 to 32%, with an average over the 3 fields of 18%. Net rates of soil loss from the fields were 30, 11, and 7 t/ha.year. However, within the fields there was a much wider range of both erosion (up to 92 t/ha.year) and deposition (up to 100 t/ha.year) rates. Most of the soil redistribution is caused by water erosion, with tillage erosion accounting for 10-20% of the soil redistribution. The soil redistribution rates were 2 orders of magnitude higher than sediment export measured at small catchment scale. Soil erosion rates are not reflected in variation in topsoil depth, because frequent tillage and incorporation of organic residues maintains a uniform topsoil depth, but soil deposition rates are closely related to topsoil depth.

The use of magnetic susceptibility to measure long-term soil redistribution

Several studies have documented the severity of recent soil erosion on the Canadian prairies where cultivation started about a century ago. Little quantitative information is available on erosion before 1960. This study attempts to quantify post- and pre-1960 soil erosion in a small cultivated basin near Saskatoon, Saskatchewan, Canada, by measuring 137Cs and magnetic susceptibility ( χ) distribution with depth. Soil cores were collected along six transects (three across closed depressions and three across the drainage channel) in the cultivated field, and one transect across an uncultivated depression. The cores were sliced into 3-cm layers and the soil analyzed for 137Cs, χ, and organic and inorganic C. High variability in χ with depth in eroding areas (as indicated by 137Cs) made it impossible to use χ to quantify past soil losses in these locations. However, these eroding upper and middle slope positions have a much higher χ than lower slope areas where soil deposition occurs and where the variability in χ with depth could be used to estimate soil deposition. Estimating soil deposition from the χ vs. depth profiles was more successful in the closed depressions than in the drainage channel, where the χ profiles may reflect the variable source areas of the materials rather than the pedological conditions. The data indicated that soil deposition since 1960 has been about 30 to 50% of that prior to 1960. This suggests that soil deposition rates, and by implication, soil erosion rates, have been relatively steady since cultivation of these soils started, although there are clear indications that the spatial pattern of deposition has varied.

Comparison of soil erosion and deposition rates using radiocesium, RUSLE, and buried soils in dolines in East Tennessee

Three dolines (sinkholes), each representing different land uses (crop, grass, and forest) in a karst area in East Tennesse, were selected to determine soil erosional and depositional rates. Three methods were used to estimate the rates: fallout radiocesium (137Cs) redistribution, buried surface soil horizons (Ab horizon), and the revised universal soil loss equation (RUSLE). When 137Cs redistribution was examined, the average soil erosion rates were calculated to be 27 t ha–1 yr–1 at the cropland, 3 t ha–1 yr–1 at the grassland, and 2 t ha–1 yr–1 at the forest. By comparison, cropland erosion rate of 2.6 t ha–1 yr–1, a grassland rate of 0.6 t ha–1 yr–1, and a forest rate of 0.2 t ha–1 yr–1 were estimated by RUSLE. The 137Cs method expressed higher rates than RUSLE because RUSLE tends to overestimate low erosion rates and does not account for deposition. The buried surface horizons method resulted in deposition rates that were 8 t ha–1 yr–1 (during 480 yr) at the cropland, 12 t ha–1 yr–1 (during 980 yr) at the grassland, and 4 t ha–1 yr–1 (during 101 yr) at the forest site. By examining 137Cs redistribution, soil deposition rates were found to be 23 t ha–1 yr–1 at the cropland, 20 t ha–1 yr–1 at the grassland, and 16 t ha–1 yr–1 at the forest site. The variability in deposition rates was accounted for by temporal differences;137Cs expressed deposition during the last 38 yr, whereas Ab horizons represented deposition during hundreds of years. In most cases, land use affected both erosion and deposition rates – the highest rates of soil redistribution usually representing the cropland and the lowest, the forest. When this was not true, differences in the rates were attributed to differences in the size, shape, and closure of the dolines.