Wind Erosion of Cropland in the Northwestern Tarim Basin

Evaluation of two empirical wind erosion models in arid and semi-arid regions of China and the USA

A numerical simulation of dust storms in China

Quantitative estimation of farmland soil loss by wind-erosion using improved particle-size distribution comparison method (IPSDC)

Field scale spatio-temporal variability of wind erosion transport capacity and soil loss at Urmia Lake

Seawater carbon and strontium isotope variations through the late Ediacaran to late Cambrian in the Tarim Basin

Woodruff and siddoway, 1965, established an equation for the estimation of soil Loss by wind erosion called Wind Erosion Equation (WEQ); solution of this equation gives the maximum amount of wind erosion under certain field conditions and is considered evidence in identifying the necessary methods for treating wind erosion in those conditions (Eltaif et al., 1991). This study aims to find out the extent to which climate change in the Samawah region of southern Iraq and Baghdad in central Iraq over a period of 34 years has affected values of soil losing by wind erosion using equation of (woodruff and siddoway, 1965) and effectiveness of this changes in soil surface roughness factor in reducing or increasing these loss. Two sites were selected located within central and southern regions of Iraq, one in Al-Jadiriya area in Baghdad governorate and the other in Samawah area in Al-Muthanna governorate. The results showed that estimated soil losing for years (1980-2013) in Al-Jadiriya decrease annually by 10-30 kg.hec.-1.year-1, while samawah increase by 240-760 kg.hec.-1.year-1. The effect of surface roughness factor was significant in reducing soil loss during period of study. Roughness factor for ridge (0.5) has reduced soil losing by 2.6 times compared to non-ridge soils (1).The ratio in semi-bridge soil (0.75) was 65%. This is due to the impact of bridge in reducing wind speed and reducing its erosivity. The general direction of soil loss indicates decrease in Al-Jadiriya area and increase in Samawah area with the case of fluctuation in soil loss between high and low of general direction line due to climate factor (C) in general equation of soil loss and it reflects ability of wind erosion, so decreased when wet conditions improved, by increased rainfall, reduced evaporation and increasing when dry conditions dominate

Air density strongly constrains the characteristics of an airflow and the resulting flow of sand and therefore, it should not be neglected in sand transport models. Although the potential importance of air density is well known, most studies on threshold velocity, saltation trajectory, and dust emission have been conducted near sea level, at a “normal” atmospheric density. In this study, utilizing the observational data from 12 meteorological stations in the Tarim Basin (TB) from 2009 to 2018, we used air density as the basis to discuss the necessity of model parameter localization. It was found that there was a significant difference in the horizontal dust flux estimated using the normal and local air densities. Using the localized air density, we re-evaluated the temporal and spatial distribution characteristics of the threshold velocity, horizontal dust flux, and wind erosion events in the TB and further quantified their distributions in all directions. The results demonstrated that the threshold velocity gradually increased from east to west and from north to south, with the maximum value occurring in the southwestern TB. The horizontal dust fluxes and wind erosion events could be classified into three types according to the seasonal variation characteristics; however, one of the main distribution characteristics was spring > summer > autumn > winter. Tazhong, Qiemo, and Ruoqiang are sand- and dust-incident frequent zones. Taking Minfeng when passing from Tazhong to Shaya as the line of demarcation, it was found that the horizontal dust fluxes and wind erosion events in the eastern region mostly occurred in the eastern direction, whereas those in the western region primarily occurred in the western direction. The results suggested that it was extremely important and necessary to localize the parameters in sand–dust models, which would also provide a more accurate climate background for the study of sand and dust in the TB.

Core Ideas Wind erosion results in loss of soil and associated C. Loss of C was measured from eroding fallow fields in eastern Washington. Eroded sediment was enriched in C compared with the parent soil. Carbon loss ranged from 0.4 to 18.5 kg C ha ‐1 across 13 erosion events. Wind erosion of cropland negatively affects soil quality and productivity in the winter wheat ( Triticum aestivum L.)–summer fallow (WW‐SF) region of the inland Pacific Northwest United States. Loss of soil diminishes the finite resource base and concurrent loss of soil organic C affects the inherent physical, chemical, and biological properties of the soil. This study aimed to quantify soil organic C loss from windblown summer fallow soils. Creep and Big Spring Number Eight samplers were used to trap sediment above an eroding soil during major wind events over an 8‐yr period. The C content of trapped sediment ranged from 6 to 11.6 g C per kg sediment. Enrichment ratios for C ranged from 0.6 to 1.9, indicating that the trapped sediment was generally enriched in C compared with the parent soil. Averaged across all sites and wind events, soil C loss from fields ranged from 0.4 to 18.5 kg C ha –1 . The ongoing decline in soil organic C since the advent of dryland farming in the region 140 yr ago is most commonly attributed to degradation by microbes and oxidation. However, our data, combined with historic accounts of wind erosion in the WW‐SF region, strongly suggest that loss of soil organic C may also be caused by wind erosion. Conservation tillage has proven an effective strategy for reducing wind erosion in the WW‐SF region and thus farmers are encouraged to further adopt conservation tillage practices to retain soil C and thereby reduce the degradation of agricultural soils by wind erosion.

Siliceous rocks of various colors and types are extensively developed within the Middle–Lower Ordovician carbonate along the Northwest Tarim Basin. Their genesis provides important insights into the evolution of basinal fluids and the associated diagenetic alterations of the carbonates. Based on petrographic, geochemical, fluid inclusion, and petrophysical analyses, this study investigates the origin of siliceous rocks within the Middle–Lower Ordovician carbonate formations (Penglaiba, Yingshan, and Dawangou formations) in the Kalpin area, Tarim Basin, and investigates the impact on hydrothermal reservoirs. The results reveal two distinct episodes of siliceous diagenetic fluids: The first during the Late Ordovician involved mixed hydrothermal fluids derived from deep magmatic–metamorphic sources, formation brines, and seawater. Characterized by high temperature and moderate salinity, it generated black chert dominated by cryptocrystalline to microcrystalline quartz through replacement processes. The second episode developed in the Middle–Late Devonian as a mixture of silicon-rich fluids from deep heat sources and basinal brines. In conditions of low temperature and high salinity, it generated gray-white siliceous rocks composed of micro- to fine crystalline quartz, spherulitic-fibrous chalcedony, and quartz cements via a combination of hydrothermal replacement and precipitation. A reservoir analysis reveals that the multi-layered black siliceous rocks possess significant reservoir potential amplified by the syndiagenetic tectonic fracturing. In contrast, the white siliceous rocks, despite superior petrophysical properties, are limited in scale as they predominantly infill late-stage fractures and vugs, mainly enhancing local flow conduits. Hydrothermal alteration in black siliceous rocks is more intense in dolostone host rocks than in limestone. Thus, thick (10–20 m), continuous black siliceous layers in dolostone and the surrounding medium-crystalline dolostone alteration zones, are promising exploration targets. This study elucidates the origins of Ordovician siliceous rocks and their implications for carbonate reservoir properties. The findings may offer valuable clues for deciphering the evolution and predicting the distribution of hydrothermal reservoirs, both within the basin and in other analogous regions worldwide.

Mass–height profile and total mass transport of wind eroded aeolian sediments from rangelands of the Indian Thar Desert

The sapping caused by prevailing wind erosion is one of the most important factors in the deterioration of earthen architecture ruins located in semi-humid areas in Qinghai Province. Based on the climatic data for many years in the area and sapping quantity of the ruins, in combination with the results of laboratory tests and simulation analyses using Fluent software in computational fluid dynamics, the influence factors for the formation and development of wind erosion diseases of the earthen architecture ruins are evaluated. Furthermore, the effect of wind velocity, duration and area of wind erosion on the sapping quantity of the ruins are assessed quantitatively according to the analysis principles of engineering geology and mechanics. This study may be helpful for prevention, monitoring and control of formation and development of sapping diseases, forecast of sapping quantity of specific wind erosion as well as its effect on the stability of the earthen ruins. © 2016, Editorial Office of Chinese Journal of Geotechnical Engineering. All right reserved.

1. Soil Erosion by Wind and Water: Problems and Prospects, R. Lal The Need for Improved Data Data Extrapolation Standardization of Methodology and Data Reliability Record Duration and Data Continuity Toward Standardization of Research Methods 2. Laboratory and Field Plots for Erosion Research, C. K. Mutchler, C. E. Murphree, and K. C. McGregor The Project Outline The Soil Erosion Process Small Plots Conclusions 3. Measuring Sediment Yield from River Basins, D. E. Walling Introduction Reliability of Existing Sediment Yield Data Designing Sediment Yield Monitoring Programs Additional Sources of Information on Sediment Yields 4. Rainfall Simulators for Soil Erosion Research, L. D. Meyer Characteristics of Rainfall Simulators Types of Rainfall Simulators Personnel Requirements and Related Equipment Rainfall Simulators: Asset or Burden? 5. The Revised Universal Soil Loss Equation, K. G. Renard, J. M. Laflen, and D. K. McCool R-factor K-factor L- and S-factor C-factor P-factor Comparison of RUSLE and USLE Summary 6. Modeling Soil Erosion, M. A. Nearing, L. J. Lane, and V. L. Lopes Mechanics of Erosion by Water Development of a Physically-Based Erosion Model Model Analysis Modeling on Watershed Scales Integrated Systems for Water Erosion Prediction 7. Research Progress on Soil Erosion Processes and a Basis for Soil Conservation Practices, C. W. Rose Types and Objectives of Soil Erosion Models Basic Approach to Sediment Erosion and Transport Erosion/Deposition Process Model A Simplified Erosion Process Model The Effect of Plot Length on Soil Loss per Unit Area Effect of Surface Contact Cover and Slope on Soil Loss 8. Erodibility and Erosivity, R. Lal and W. Elliot Soil Erosion Process Soil Erodibility Summary 9. Assessing Vegetative Cover and Management Effects, M. A. Stocking How Vegetative Cover and Management Work Key Areas in Crop Cover and Management Research Methodologies 10. Monitoring the Impact of Soil Erosion on Crop Productivity, F. J. Pierce and R. Lal The Need for Erosion-Productivity Research Approaches to the Problem Toward a Minimum Data Set The Erosion-Productivity MDS Model Building and Validation Summary and Conclusions 11. Wind Erosion, E. L. Skidmore Soil Erodibility by Wind Wind Erosivity Ridge Roughness Field Length Vegetative Factor A Wind Erosion Model Management Effects Conclusions 12. Methods for Investigating Basic Processes and Conditions Affecting Wind Erosion, E. L. Skidmore, L. J. Hagen, D. V. Armbrust, A. A. Durar, D. W. Fryrear, K. N. Potter, L. E. Wagner, T. M. Zobeck Wind Databases and Simulation Particle Detachment and Transport Aggregate Stability Dry Aggregate Size Distribution Surface Roughness: Shelter Angle Distribution Surface Roughness: Digitization of Pin Meter Photos Surface Crusting Loose Surface Particles Soil Wetness Canopy Structure Field Scale Wind Erosion Measurement Index

Several soil conservation practices are used to reduce water erosion and ensure sustainable agriculture. An effective crop management practice is intercropping, in which two or more crops with different architectures and vegetative cycles are grown simultaneously in the same area. We hypothesized that intercropping of corn and jack-bean increases soil cover and reduce soil erosion by water in comparison to monocropping. The objective of this study was to evaluate the effects of different crop systems on soil cover and on soil erosion by water. Soil and water losses from a Typic Hapludox were measured under the following systems: corn cultivation (CO), jack-bean cultivation (JB), intercropping of corn and jack-bean (IC), and bare soil (BS), as a reference for maximum erosion rates. For each crop system, erosion plots with dimensions of 12 × 4 m were set up in the field on a 0.12 m m−1 slope gradient. The experiment was carried out under natural rainfall, over three crop seasons (November to March) from 2011 to 2014. The soil cover index of the systems was monitored during crop growth, and rainfall erosivity for the crop seasons was calculated according to the EI30 index to interpret soil and water losses. A set of linear mixed models was fitted to relate soil losses to rainfall erosivity, crop systems, and soil cover. The average rainfall erosivity in the study area was 6,132 MJ mm ha−1 h−1 per crop season. The results indicate that water losses are directly related to erosivity and are less influenced by soil cover and cultivation systems than the soil losses. A linear maximum value of the soil cover index was achieved 70 days after sowing. Intercropping exhibited greater soil cover than single crops. Total soil losses from the three seasons display the trend: BS > CO > JB > IC. The best fitted model of the linear mixed models indicates that soil loss responses are strongly correlated with rainfall erosivity and soil cover, which nullified the influence of the crop systems in the model.

Soil wind erosion is a major concern of the agricultural community in the inland Pacific Northwest (iPNW) United States. This study quantitatively predicts dust emissions from agroecological classes (AECs) of iPNW based on soil and land use types in response to climate change. The Wind Erosion Prediction System (WEPS) was used to simulate daily soil and PM10 (particulate matter ≤10 μm in aerodynamic diameter) loss at 29 meteorological stations across the iPNW. From 2009 to 2018, annual soil and PM10 loss decreased 1.18 and 0.05 kg m−2 yr−1, respectively. We presume that this decrease may be due to decreased wind speed, rather than other parameters like precipitation or solar radiation. St. John, WA had not only the highest annual soil loss but also the greatest mean wind speed and number of events with wind speeds >8 m/s. However, Lind, WA appeared to have greater soil surface erodibility in terms of greater rates of hourly soil and PM10 loss. Wind erosion occurred most frequently during March and April. The average maximum annual soil and PM10 loss in the grain‐fallow stable (24.7 and 0.63 kg/m2, respectively) exceeded that of all other agroecosystems. This suggested that maintaining crop cover is critical for protecting the soil surface from erosion.

The Arabian Peninsula is among the major dust sources on Earth. Here, dust storms occur frequently as a result of the action of surface winds on desert surface such as the Empty Quarter Desert located in southern Arabian Peninsula. Despite being a frequent occurrence, no direct measurement of dust emission in this region existed to date. In summer 2022, the WInd-blown Sand Experiment (WISE) kicked off in the Empty Quarter area located in southern United Arab Emirates (UAE). The aim of the experiment is to quantify dust emission from this major dust source through direct observations. A full set of instrumentation is being operated to study saltation, winds, temperature, humidity, radiative fluxes, physical and optical properties of dust aerosols, atmospheric electric field, and soil properties. In this presentation, we describe the instrumentation being used in WISE UAE and we show some preliminary results during different weather regimes such as strong wind erosion, local convection, dense radiation fog and land-sea breeze. The analysis of atmospheric electric field data suggests the presence of relatively higher electric field at the onset of sea breeze occurrence and wind erosion events. The detailed investigation on relative humidity, frictional velocity, dust particle size distribution impact on the electric field will be presented. WISE is a first-of-its-kind experiment in the region and it aims ultimately at improving dust parametrizations in numerical models. We hope that this presentation at the EGU can trigger collaborations in this direction.