Erosion Bridge Research Articles

Потери почвы от дефляции в Ростовской области

Purpose: collection, analysis and generalization of data on wind speed and the intensity of deflation processes in Rostov region, that helps assessing the quantitative side of soil loss depending on wind speed, weather conditions, terrain, tillage method and other factors, and development of wind corridors for the conditions of the region under consideration. Materials and methods. The research was carried out on chestnut soils, southern and ordinary chernozems of the agricultural enterprise “Rassvet” of Aksai district and the agricultural enterprise “Krasnoarmeyskoe” of Oryol district of Rostov region, and the results of other scientists, who have been conducting research in Rostov region since 1969, were analyzed and summarized. Wind speed was measured with anemometers at a height of 2 m above the soil level, and the soil mass moved by winds was determined by the Erosion bridge (pin method) and dust collectors of our own design. Methods of analysis and synthesis as a systematic approach to achieving the goal were used. Results. The wind direction and speed in Rostov region depend on the seasonal position of pressure centers: the Siberian maximum in winter and the Azores in summer. Over the 54 years of research from 1969 to 2023, dust storms and drifting snow were observed 11 times, i.e. once every five years. Mathematical processing of long-term research data made it possible to obtain dependencies for assessing the effect of wind speed on soil removal on average in 1 hour, to determine soil removal coefficients, to propose zoning of the region into five deflationary regions, to develop a map diagram of deflationary zones and wind corridors of Rostov region. Conclusions. The greatest soil losses in wind-impact directions were in 1969 up to 800–900 t/ha for a duration of 300 h, in 1972 – 170–200 t/ha for a duration of 96 h; in 1984, with a daytime wind speed of 10–14 m/s with gusts of up to 25–30 m/s for a duration of 142 h, soil losses amounted to 218 t/ha.

Modern techniques for monitoring wind soil erosion

The article presents a scientific literature review in the field of modern methods of monitoring wind erosion of soils such as: visual indicators of erosion, erosion bridge, close-range photogrammetry, cesium-137 and remote sensing cover. The brief description of each method, advantages and disadvantages, conditions and limitations of their applicability are given. When choosing the method, it is necessary to take into account the monitoring conditions, the area of the territory under consideration and the scale of research, time frames, financial and labor resources. It has been established that the most relevant, economically justified and promising, especially on large territories, are the remote sensing methods, which allow monitoring on different scales, and not only estimating the erosion activity, but also predicting it, thus providing the parties concerned with the necessary information for making right, prompt and timely economic decisions, aimed both at combating wind erosion and elimination of its consequences, and for organizing preventive measures as well. To improve the effectiveness of these methods it is also necessary to create databases, expand and accumulate soil information that can help verify, refine, process and calibrate the satellite data obtained. In order to understand aeolian processes and dust particle transport mechanisms one should create integrated methods that include remote sensing data, meteorological data, on the basis of which the improved models and maps would be developed, and erosion processes would be predicted. The scientific literature is mostly devoted to the interpretation of wind erosion in arid and semi-arid zones. The possibility of satellite monitoring of soil erosion in arable fields remains poorly studied. There are also practically no research results available on the transport of chemicals with micro-particles due to wind erosion. Both in Russia and abroad the attempts are made in soil erosion modelling, but the quality of the models is very limited by the lack of field data required for their calibration and verification. Eroded soils in the country are still identified using ground-based methods. However, field studies can only be conducted in a very limited area, in a few key points, and as a matter of fact it is quite complicated to conduct field studies on actively used agricultural lands.

Sediment clues in flood mitigation: the key to determining the origin, transport, and degree of heavy metal contamination

Abstract This study seeks to identify sediment sources, quantify erosion rates, and assess water quality status via sediment fingerprinting, the Modified Laser Erosion Bridge (MLEB) method, and various pollution indices (PIs), respectively, in the humid tropics (Malaysia). Geochemical elements were used as tracers in sediment fingerprinting. Erosion rates were measured at 3,241 points that encompass high conservation value forests (HCVFs); logged forests (LFs); mature oil palm (MOP); and mature rubber (MR) plantations. Annual erosion rates were 63.26–84.44, 42.38, 43.76–84.40, and 5.92–59.32 t ha−1 yr−1 in the HCVF, LF, MOP, and MR, respectively. Via sediment fingerprinting, logging and agricultural plantations were identified as the major contributors of the sediment. PIs also indicated the highest level of pollution in those catchments. This study highlighted three main messages: (i) the feasibility and applicability of the multiproxy sediment fingerprinting approach in identifying disaster-prone areas; (ii) the MLEB as a reliable and accurate method for monitoring erosion rates within forested and cultivated landscapes; and (iii) the adaptation of PIs in providing information regarding the status of river water quality without additional laboratory analyses. The combination of these approaches aids in identifying high-risk and disaster-prone areas for the prioritisation of preventive measures in the tropics.

Soil erosion in disturbed forests and agricultural plantations in tropical undulating terrain: in situ measurement using a laser erosion bridge method

Abstract The rapid growth of agricultural plantations and climatic extremes has raised concerns pertaining to enhanced soil erosion. Soil erosion studies are still relatively limited in Malaysia. In this study, soil erosion in four sites such as high conservation value forests (HCVFs), logged forest (LF), mature oil palm (MOP), and mature rubber (MR) within the Kelantan River Basin was measured. A total of 3,207 measurements were conducted via the Modified Laser Erosion Bridge in all sites over 1 year. Results of soil erosion are 87.63, 25.45, 8.44, and 5.90 t ha−1 yr−1 for the HCVF, LF, MOP and MR, respectively – classified as very severe (HCVF), very high (LF), moderate (MP) and slight (MR) according to the Indian condition classification. Steep slope gradient (significant positive correlation to erosion) and logging are the main factors attributed to the high erosion rates. This is to be further explored in the future and more detailed studies should be conducted on the HCVF and LF areas, respectively. Mitigation measures and sustainable agricultural practices should be planned to control and reduce soil erosion.

Impact of forest conversion to agricultural plantation on soil erosion

Agriculture in Malaysia makes up to twelve percent of the nation’s GDP and is supplying one-third of the world rubber export. Ambitious agriculture demand increases the intensity of forest conversion which is driven to the soil erosion. Thus, this study is to measure and analyse the impact of forest conversion on soil erosion relate to some manipulated variables such as slope, bulk density, soil moisture, canopy openness and ground cover, where rainfall and soil type are constant within the sites. Two different land-uses of High Conservation Value Forest (HCVF) and Mature Rubber Plantation of Timber Latex Clone (MRP) were selected around Kelantan state, due to the high land conversion compared to the other states of West Malaysia. Ground height change was monitored by using Modified Laser Erosion Bridge (MLEB) in between 17 to 48 transects. The result found that the annual soil erosion rate was 76.12 t.ha-1.yr-1 for HCVF is higher compared to the MRP was 6.37 t.ha-1.yr-1. Terrace soil conservation technique is practiced for MRP helps in reducing soil movement resulted significant low erosion rate compared to the HCVF. The results indicate that even a relatively limited forest conversion can be assumed to have a significant effect on regional soil erosion rate.

Fine-Resolution Repeat Topographic Surveying of Dryland Landscapes Using UAS-Based Structure-from-Motion Photogrammetry: Assessing Accuracy and Precision against Traditional Ground-Based Erosion Measurements

Structure-from-motion (SfM) photogrammetry from unmanned aerial system (UAS) imagery is an emerging tool for repeat topographic surveying of dryland erosion. These methods are particularly appealing due to the ability to cover large landscapes compared to field methods and at reduced costs and finer spatial resolution compared to airborne laser scanning. Accuracy and precision of high-resolution digital terrain models (DTMs) derived from UAS imagery have been explored in many studies, typically by comparing image coordinates to surveyed check points or LiDAR datasets. In addition to traditional check points, this study compared 5 cm resolution DTMs derived from fixed-wing UAS imagery with a traditional ground-based method of measuring soil surface change called erosion bridges. We assessed accuracy by comparing the elevation values between DTMs and erosion bridges along thirty topographic transects each 6.1 m long. Comparisons occurred at two points in time (June 2014, February 2015) which enabled us to assess vertical accuracy with 3314 data points and vertical precision (i.e., repeatability) with 1657 data points. We found strong vertical agreement (accuracy) between the methods (RMSE 2.9 and 3.2 cm in June 2014 and February 2015, respectively) and high vertical precision for the DTMs (RMSE 2.8 cm). Our results from comparing SfM-generated DTMs to check points, and strong agreement with erosion bridge measurements suggests repeat UAS imagery and SfM processing could replace erosion bridges for a more synoptic landscape assessment of shifting soil surfaces for some studies. However, while collecting the UAS imagery and generating the SfM DTMs for this study was faster than collecting erosion bridge measurements, technical challenges related to the need for ground control networks and image processing requirements must be addressed before this technique could be applied effectively to large landscapes.

The new volumetric approach for field measurements of rill erosion

Erosion on agricultural soils in Czech Republic threats seriously their production and nonproduction functions. Erosion have devastating effect on fertile topsoil of agricultural soils, reduces thickness of soil profile and nutrients and humus content, deteriorate physical, chemical and biological properties of soil. At Brno University of Technology in Czech Republic was designed and realized equipment the soil erosion bridge, which allows soil surface profile measurement and quantifies volume of erosion rills, which can occur after heavy rainfall. The main objective was to develop a method for volumetric quantification of erosion rills during heavy rainfall season. Using new equipment soil surface profile was measured directly in field during 4 years (2007–2010). New equipment consists of three parts. The first equipment is a square frame with an inside dimension of 4 m2. The second equipment is removable profile, which serves for movement of soil erosion bridge. The third equipment is soil erosion bridge. The soil erosion bridge serves to volumetric quantification of rill erosion. The more effective way of data processing was developed. It was developed a software, by which it is possible automatically transfer rill surface profile to digital form. In South Moravian Region in Czech Republic was selected case study area with typical very steep sloped relief with loess soil. The measurement was carried out on research plots with a slope of more than 10%. More than 1300 cross sections of soil surface profile were measured using new type of soil erosion bridge. From these profiles it was possible to calculate volume of eroded soil from research plots. The results were always in excess of 100 t.ha–1.rok–1. This is a value many times higher than tolerated limit of soil loss in Czech Republic. Thanks to this new equipment, it is possible to quantify soil loss from plot threatened of water erosion. The advantage of this equipment is its using during vegetable season when soil surface is overgrown with vegetation and crops are higher growth.

Fenceline contrasts: grazing increases wetland surface roughness

A warming earth has lost substantial mountain-stored frozen fresh water, thus generating a pressing need for greater liquid–water storage within upper-elevation riparian systems. Liquid–water storage can be enhanced by avoiding microtopographic channels that facilitate land drainage and rapid runoff. A number of authors have attributed certain forms of wetland hummocks and inter-hummock channels to grazing livestock but there is little evidence in the scientific literature for a cause and effect mechanism. We used comparisons at six fencelines on four meadow and wetland complexes to test the null hypothesis that grazing management makes no difference in hummocks and inter-hummock channels measured as surface roughness. Surface roughness was measured both photogrammetrically (photo) and with an erosion bridge (EB), and the measurements expressed as surface roughness indices (SRIs). Wetland surface roughness inside fenced areas was 44 (EB) and 41 (photo). Wetland surface roughness outside fenced areas was more than 50 % higher (p < 0.0001), measuring 76 (EB, n = 6) and 62 (photo, n = 4). The site with the longest period of conservation management (50+ years) had the lowest inside EB SRI at 27. The two independent measurement methods, EB and photo, yielded similar, correlated results (R = 0.71, n = 8). Historical aerial photography provides supporting evidence for our findings. We reject the null hypothesis and while we suspect macrotopography, hydrology, soil type, and climate are factors in hummock formation, our evidence supports the thesis that hummocks formed surface-down by inter-hummock channels result primarily from grazing by domestic livestock.

Relationships of aeolian erosion and deposition with LiDAR-derived landscape surface roughness following wildfire

The reduction of vegetation by wildfire can subject stable soil surfaces to increased aeolian transport. Vegetation and associated microtopography function as surface roughness elements that influence the entrainment, transport, and deposition of sediment by wind in burned and unburned semiarid shrublands. We examined whether surface roughness derived from LiDAR can explain variability in aeolian surface change following wildfire in loess soils of a cold desert shrub steppe in SE Idaho, USA. Erosion bridges were installed in Fall 2007, following a late summer wildfire to monitor soil surface change at sites in burned and downwind unburned areas. Surface elevation measurements were made when the erosion bridges were installed and again in Fall 2008. Surface change was determined from the difference in relative elevation between the two dates. Airborne LiDAR data were acquired in Fall 2007 following erosion bridge installation. Surface roughness was calculated at 2-m raster resolution using the standard deviation of all LiDAR elevations within the 2-m cells, after elevations were detrended to remove the effects of topographic slope. Surface change varied as a function of surface roughness among burned and unburned surfaces, with net erosion occurring on the relatively smooth, burned surfaces and net deposition occurring on the rough, unburned surfaces. Site mean surface change decreased linearly as a function of the inverse of site mean surface roughness ( r 2 = 0.77, p < 0.00). Quantile regression analysis indicated that changes in surface roughness were related to proportionally greater changes in erosion compared to deposition. Analysis of surface change at finer spatial scales suggested that aeolian processes occurred with strong spatial patterns on burned, but not unburned surfaces. Future research to examine relationships between aeolian transport and fine spatial resolution topographic variability, for example from ground-based LiDAR systems, is recommended.

A field study on cost‐effectiveness of five erosion control measures

PurposeThe purpose of this study is to quantitatively evaluate five erosion control measures at a residential development area in Louisiana, USA in order to provide Best Management Practices (BMPs) that have been tested in the field with demonstrated cost‐effectiveness.Design/methodology/approachA total of six testing sites at a nine‐degree slope were used in parallel to study five erosion control measures with one being the control site (no protection). Soil erosion rate was quantified using the erosion bridge method. Soil underlying the study area was analyzed for surface runoff potential. Precipitation was monitored using a Sigma rain gauge. Analysis of variance (ANOVA) and Student Newman‐Keuls Post‐Hoc ANOVA analysis were conducted to evaluate statistical significance of erosion control effectiveness. Ratio of soil erosion rate reduction to cost of each control measure is also analyzed.FindingsAll erosion control measures studied were very effective in reducing soil erosion for soils with high runoff potential, ranging from 75 percent to about 100 percent reduction in soil erosion rate. The most effective soil erosion protection was observed by Geojute fabric and Curlex blanket with greater than 90 percent reduction in soil erosion rate. However, after factoring‐in cost, straw bedding was observed to be five times as cost‐effective as Geojute fabric and Curlex blanket. The most cost‐effective measure is temporary seeding using perennial rye grass. For each dollar spent, about 12 tons of soil per acre per year will be prevented from eroding.Originality/valueThe study evaluated erosion control measures in the field with quantitative cost‐effectiveness analyzed. Besides enforcement, providing practical and cost‐effectiveness control measures that have been tested in the field is critical for actual implementation of erosion control measures.

Erosion and Nutrient Loss on Sloping Land under Intense Cultivation in Southern Vietnam

AbstractTo help improve the well‐being of the local people, a joint Vietnamese‐UK team set out to establish a way of estimating soil and nutrient losses under different land management scenarios, using field data extrapolated through remote sensing and GIS, to obtain catchment‐wide estimates of the impact of land cover change. Immigration from remote provinces to the Dong Phu District of Binh Phuóc Province, about 120 km north of Ho Chi Minh City, has led to disruption of soil surface stability on easily eroded clayey sandstones, creating rapid nutrient depletion that affects crop yields and siltation in the channel of the Rach Rat river downstream. The poor farmers of the areas see crop yields drop dramatically after two or three years of cultivation due to the fertility decline. Soil loss varies dramatically between wet season and dry season and with ground cover. Erosion bridge measurements showed a mean loss of 85.2 t ha−1 y−1 under cassava saplings with cashew nuts, 43.3 t ha−1 y−1 on uncultivated land and 41.7 t ha−1 y−1 under mature cassava. The rates of erosion were higher than those reported in many other parts of Vietnam, reflecting the high erodibility of the friable sandy soils on the steep side‐slopes of the Rach Rat catchment. However, although the actual measurements provide better soil loss data than estimates based on the parameters of soil loss equations, a large number of measurement sites is needed to provide adequate coverage of the crop and slope combinations in this dissected terrain for good prediction using GIS and remote sensing.

Local Knowledge and Economic Realities Affecting Soil Erosion in the Rach Rat Catchment, Vietnam

AbstractSeveral parts of Binh Phuóc Province, southern Vietnam, suffer from degraded soils and vegetation as a result of both natural erosion of weak mud rocks and sandstones and intensive human activity, especially through land clearing for agriculture on unstable slopes, deforestation, and abandonment of poor farmland. The underlying cause of this land degradation has been the farming habits of migrants of varying ethnic groups who have settled in the area since 1980. The indigenous farming knowledge of these people and the role of that knowledge in soil erosion were examined by a series of household surveys. They enabled farming practices to be related to ground cover established from a 2002 Landsat 7 ETM (Enhanced Thematic Mapper), and erosion data from a series of erosion bridge measurements. A GIS (Geographical Information System) approach was piloted as a means of identifying areas vulnerable to erosion. This could then be combined with the understanding of farming practices to reveal the relative roles of farmer behaviour, crop cover, and slope and soil characteristics in the erosion process. Land use, local people's knowledge and economic realities are the main factors, as well as natural conditions, that drive this land degradation.

Long-term erosion and surface roughness change of rain-forest terrain following selective logging, Danum Valley, Sabah, Malaysia

When rain forest is logged, rills and gullies are often initiated on heavily disturbed and compacted terrain components; whether and for how long they continue to enlarge following logging is critical as regards the recovery and sustainability of the regenerating forest. This paper examines these two issues in logged rain forest in northeastern Borneo. Results are presented of an investigation into how soil erosion rates and surface topography varies in selectively logged forests at different stages of regeneration (up to 15 years after logging) in Danum Valley, eastern Sabah, Malaysia. Measurements were made of changes in ground level and surface roughness at over 100 transect sites over periods of 1–15 years using the erosion bridge (microprofiler) technique. In the complex mosaic of the post-logging regenerating forest, attention focused on key features, notably abandoned logging tracks, gullies, heavily disturbed or compacted areas and road-related landslides and comparisons are made with primary forest terrain. The role of extreme rainstorms in controlling the temporal pattern of post-logging erosion in both regenerating and primary forest is demonstrated. The different situations in which rills and gullies initiated during or following logging enlarge or disappear in post-logging terrain are highlighted. The implications of the results for slope evolution and sustainable rain-forest management policies are briefly considered.

Soil microtopography on grazing gradients in Chihuahuan desert grasslands

The significant impacts of livestock in the creation of piospheres centered on water points is the loss of soil microtopography across a ‘landscape’ that has been influenced by many years of livestock grazing. The size, height, and spatial distribution of micromounds and surrounding depressions were measured by a modified erosion bridge at three distances (50, 450, and 1050 m) from water points in desert grassland pastures in the Jornada Basin, New Mexico, USA. Plots at 50 m had fewer micromounds and the mounds were smaller than those recorded on the more distant plots. Microtopography of plots at 450 m from water was not significantly different from that recorded at 50 m. Microtopography of plots that were 1050 m from water points was significantly different from that of plots nearer water points. Strong correlation between microtopography and the cover of long-lived perennial grasses ( R 2=91%) was found, such dependence could be used for assessing the trend in organic matter content that is in concordance with that of microtopography. Loss of microtopography from the impact of livestock in piospheres exacerbates erosion processes and contributes to desertification.

Ground‐level changes after wildfire and ploughing in eucalyptus and pine forests, Portugal: implications for soil microtopographical development and soil longevity

AbstractSoil level changes over four years at 50 sites in three types of post‐fire eucalyptus and pine forest management practices (natural pine seedling regeneration; eucalyptus regrowth from coppiced stumps; and deep‐(rip‐) ploughed areas planted with eucalyptus seedlings) in the Águeda Basin, Portugal are reported. Average ground lowering at regrowth sites was high during the first year after fire (up to an estimated 18 mm), declining sharply by the third year with vegetation growth and litter cover development. In the first year after rip‐ploughing, there was greater surface lowering (up to 27 mm recorded), with recovery within three–four years. This sharp post‐ploughing reduction in soil loss is attributed to stone lag development through erosion of fines. Soil erosion resulting from a wildfire—rip‐ploughing cycle is estimated to be up to 174 t ha−1, which would lead to ultimate physical degradation for typically thin soils within 50–100 years. Soil surface roughness decreased slightly or remained virtually stable for the moist Águeda Basin stony soil compared with a model of increased roughness for dry Mediterranean stony soils. This difference is attributed to moist conditions encouraging vegetation growth and rapid fermentation of organic matter together with transported sediment infilling surface indentations. The value of a ground‐level change approach, and of the soil erosion bridge in particular, in soil erosion studies is discussed. Copyright © 2002 John Wiley &amp; Sons, Ltd.

The effectiveness of bench-terracing and afforestation for erosion control on Raña sediments in central Spain

Bench-terracing and Pinus afforestation have been extensively adopted as a means of soil conservation in Spain. This paper questions the appropriateness of this technology to extensively gullied soils and sediments of the Rana formation of central Spain. Bench-terracing has markedly altered the characteristics of the surface soil horizon as compared with nearby undisturbed matorral (natural scrub) vegetation. The construction process and resultant bench-terrace morphology have imposed a new, more spatially structured pattern in soil properties giving enhanced opportunities for overland flow generation and erosion. The terracing has exposed subsurface Bt horizons on inner treads and lower risers, producing a very compact clay rich surface horizon, low in organic carbon and of poor structural stability. Despite subsoiling hydraulic conductivity is very low. Excavated soil material is ploughed sideways to partially bury the original surface horizon and form part of the next riser downslope. Downslope drainage on the terraces gives rise to soil moisture contents approaching saturation on the lower risers and treads. Consequently only small rainfall inputs are required to initiate ponding and overland flow generation on sloping treads. Rainfall simulation demonstrates the importance of antecedent soil moisture to runoff generation, and the role of vegetation and organic matter in retaining water. Erosion bridge measurements show that erosion rates on sloping treads are as high as those recorded on gully sidewalls. Gully sidewall erosion is also accelerated by runoff waters shed from terrace treads. Management of native matorral vegetation may provide a more sustainable approach to soil conservation than bench terracing with afforestation.

The soil erosion bridge: A device for micro‐profiling soil surfaces

AbstractThe soil erosion bridge is a simple, robust, cheap, lightweight device comprising a bar which, when mounted on two stakes, provides a stable datum for micro‐profiling the soil surface beneath. Its main advantage over similar devices is the unique combination of mounting clamps, which allow for variation in the distance and angle with respect to the vertical of the mounting stakes without loss of accuracy. The design, installation and measurement procedures are described. Applications and limitations are discussed.