Contemporary and future dust sources and emission fluxes from gypsum- and quartz-dominated eolian systems, New Mexico and Texas, USA

Recent research on dust emissions from eolian dunes seeks to improve regional and global emissions estimates and knowledge of dust sources, particularly with a changing climate. Dust emissions from dune fields can be more accurately estimated when considering the whole eolian system composed of active to stabilized dunes, interdunes, sand sheets, and playas. Each landform can emit different concentrations of dust depending on the supply of silt and clay, soil surface characteristics, and the degree to which the landforms are dynamic and interact. We used the Portable In Situ Wind Erosion Laboratory (PI-SWERL) to measure PM10 (particulate matter <10 μm) dust emission potential from landforms in two end-member eolian systems: the White Sands dune field in New Mexico (USA), composed of gypsum, and the Monahans dune field in west Texas, composed of quartz. White Sands is a hotspot of dust emissions where dunes and the adjacent playa yield high dust fluxes up to 8.3 mg/m2/s. In contrast, the active Monahans dunes contain 100% sand and produce low dust fluxes up to 0.5 mg/m2/s, whereas adjacent stabilized sand sheets and dunes that contain silt and clay could produce up to 17.7 mg/m2/s if reactivated by climate change or anthropogenic disturbance. These findings have implications for present and future dust emission potential of eolian systems from the Great Plains to the southwestern United States, with unrealized emissions of >300 t/km2/yr.

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Physical Crust Formation on Sandy Soils and Their Potential to Reduce Dust Emissions from Croplands

Land ◽

10.3390/land9120503 ◽

2020 ◽

Vol 9 (12) ◽

pp. 503

Author(s):

Heleen Vos ◽

Wolfgang Fister ◽

Frank Eckardt ◽

Anthony Palmer ◽

Nikolaus Kuhn

Keyword(s):

Wind Erosion ◽

Sandy Soils ◽

Soil Surface ◽

Free State ◽

Cone Penetrometer ◽

Crust Formation ◽

Dust Emissions ◽

Dust Flux ◽

Dust Sources

The sandy croplands in the Free State have been identified as one of the main dust sources in South Africa. The aim of this study was to investigate the occurrence and strength of physical soil crusts on cropland soils in the Free State, to identify the rainfall required to form a stable crust, and to test their impact on dust emissions. Crust strength was measured using a fall cone penetrometer and a torvane, while laboratory rainfall simulations were used to form experimental crusts. Dust emissions were measured with a Portable In-Situ Wind Erosion Laboratory (PI-SWERL). The laboratory rainfall simulations showed that stable crusts could be formed by 15 mm of rainfall. The PI-SWERL experiments illustrated that the PM10 emission flux of such crusts is between 0.14% and 0.26% of that of a non-crusted Luvisol and Arenosol, respectively. The presence of abraders on the crust can increase the emissions up to 4% and 8% of the non-crusted dust flux. Overall, our study shows that crusts in the field are potentially strong enough to protect the soil surfaces against wind erosion during a phase of the cropping cycle when the soil surface is not protected by plants.

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Quantification of iron-rich volcanogenic dust emissions and deposition over the ocean from Icelandic dust sources

Biogeosciences ◽

10.5194/bg-11-6623-2014 ◽

2014 ◽

Vol 11 (23) ◽

pp. 6623-6632 ◽

Cited By ~ 25

Author(s):

O. Arnalds ◽

H. Olafsson ◽

P. Dagsson-Waldhauserova

Keyword(s):

Large Scale ◽

Dust Emission ◽

Dust Storms ◽

Dust Event ◽

Dust Deposition ◽

Dust Emissions ◽

Dust Sources ◽

Basaltic Composition ◽

Limiting Nutrient ◽

Dust Events

Abstract. Iceland has extremely active dust sources that result in large-scale emissions and deposition on land and at sea. The dust has a volcanogenic origin of basaltic composition with about 10% Fe content. We used two independent methods to quantify dust emission from Iceland and dust deposition at sea. Firstly, the aerial extent (map) of deposition on land was extended to ocean areas around Iceland. Secondly, surveys of the number of dust events over the past decades and calculations of emissions and sea deposition for the dust storms were made. The results show that total emissions range from 30.5 (dust-event-based calculation) to 40.1 million t yr−1 (map calculation), which places Iceland among the most active dust sources on Earth. Ocean deposition ranges between 5.5 (dust event calculations) and 13.8 million tons (map calculation). Calculated iron deposition from Icelandic dust ranges between 0.567 and 1.4 million tons, which are distributed over wide areas (>370 000 km2) and consist of fine reactive volcanic materials. The paper provides the first quantitative estimate of total dust emissions and oceanic deposition from Iceland. Iron is a limiting nutrient for primary production in the oceans around Iceland, and the dust is likely to affect Fe levels in Icelandic ocean waters.

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Determining soil moisture and sediment availability at White Sands Dune Field, New Mexico, from apparent thermal inertia data

Journal of Geophysical Research Atmospheres ◽

10.1029/2009jf001378 ◽

2010 ◽

Vol 115 (F2) ◽

Cited By ~ 45

Author(s):

Stephen Scheidt ◽

Michael Ramsey ◽

Nicholas Lancaster

Keyword(s):

Soil Moisture ◽

New Mexico ◽

Thermal Inertia ◽

Dune Field ◽

White Sands

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Transport and mixing of eolian sand from local sources resulting in variations in grain size in a gypsum dune field, White Sands, New Mexico, USA

Sedimentary Geology ◽

10.1016/j.sedgeo.2015.12.010 ◽

2016 ◽

Vol 333 ◽

pp. 184-197 ◽

Cited By ~ 8

Author(s):

Richard P. Langford ◽

Thomas E. Gill ◽

Slade B. Jones

Keyword(s):

Grain Size ◽

New Mexico ◽

Dune Field ◽

Eolian Sand ◽

Local Sources ◽

Transport And Mixing ◽

White Sands

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Dune deformation in a multi-directional wind regime: White Sands Dune Field, New Mexico

Earth Surface Processes and Landforms ◽

10.1002/esp.3700 ◽

2015 ◽

Vol 40 (7) ◽

pp. 925-941 ◽

Cited By ~ 14

Author(s):

Anine Pedersen ◽

Gary Kocurek ◽

David Mohrig ◽

Virginia Smith

Keyword(s):

New Mexico ◽

Wind Regime ◽

Dune Field ◽

White Sands

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Controls of aeolian dune height on cross-strata architecture: White Sands Dune Field, New Mexico, U.S.A.

Journal of Sedimentary Research ◽

10.2110/jsr.2020.138 ◽

2021 ◽

Vol 91 (5) ◽

pp. 495-506

Author(s):

Feifei Zhao ◽

Benjamin T. Cardenas ◽

Wonsuck Kim

Keyword(s):

New Mexico ◽

Positive Trend ◽

Single Event ◽

Dune Field ◽

Storage Mechanism ◽

Temporary Storage ◽

Aeolian Dunes ◽

Dune Height ◽

White Sands ◽

Thickness Measurements

ABSTRACT The stratal types composing aeolian dunes preserve a record of the transport and sorting of grains and are categorized into: 1) grainflow strata, 2) grainfall laminae, and 3) wind-ripple laminae. The arrangement of these deposits in the cross beds of a formative dune is largely unexplored. Here, field results from White Sands Dune Field, New Mexico, USA, are used to test the hypothesis that dune height controls the arrangement, abundance, and geometry of cross-stratification types. Grainflow thicknesses and deposit widths were measured on wind-scoured stoss-side exposures of seven crescentic dunes with heights ranging from 1.7 m to 11.2 m. Dozens of grainflow thickness measurements were taken along transverse-oriented strata normal to the crest on each dune. The results show that grainflow thickness averages from 1 cm to 4 cm. These data show a positive trend between mean grainflow thickness and dune height but only for the grainflow thicknesses measured at the bases of dunes. The tallest dune (11.2 m) produced many thick grainflow packages of 10 cm to 30 cm in which individual grainflow strata were indistinguishable from each other. This amalgamation was also found to be characteristic of larger dunes—the product of a lack of grainfall deposits separating individual grainflows. These differences in grainflow strata at the bases of dune lee slopes are linked to the temporary storage of sediment along the upper parts of lee slopes. In taller dunes with longer lee slopes, amalgamated grainflows which require multiple avalanche events and take longer time to reach the base transport temporarily stored sediment at upper parts of the slope. This allows time for wind ripples to rework accumulations near the base, where grainfall deposition is also limited. Shorter dunes lack this temporary storage mechanism, as individual grainflows can move across the entire lee slope in a single event, and grainfall accumulates across the entire lee slope. These stratigraphic measurements and process-based understanding will be useful in estimating original dune height in ancient cross-strata and will lead to a better interpretation of aeolian stratigraphy.

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Crust formation on sandy savanna cropland soils and their potential to reduce dust emissions

10.5194/egusphere-egu21-1041 ◽

2021 ◽

Author(s):

Heleen Vos ◽

Wolfgang Fister ◽

Frank Eckardt ◽

Anthony Palmer ◽

Nikolaus Kuhn

Keyword(s):

South Africa ◽

Wind Erosion ◽

Dust Emission ◽

Soil Surface ◽

Free State ◽

Management Approach ◽

Crust Formation ◽

Dust Emissions ◽

Soil Crusts ◽

The Impact

<p>After the conversion to cropland, dust emissions can lead to the degradation of agricultural soil. There are also offsite effects of dust emission due to the impact of dust on climate, human health, and global biogeochemistry. The sandy croplands in the Free State of South Africa have been identified by Eckardt et al. (2020) as one of the main dust sources in South Africa. The Free State is a semi-arid province that is dominated by grassland plains and 31% of the land is utilized for agriculture. The emission of dust from sandy Luvisols and Arenosols, which are typically used for crop farming, is mainly controlled by the cropping cycle. In general, the fields are left bare from at least July until December. When the fields have low surface roughness and stubble cover, the presence of physical soil crusts could be one of the main factors protecting the surface against wind erosion. Crusts can form before or during the growing season, before the vegetation cover is too extensive and protects the soil from raindrop impact. The aim of this study was to investigate the occurrence and strength of physical soil crusts on cropland soils in the Free State, to identify the rainfall required to form a stable crust, and to test their impact on dust emissions. Crust strength was measured using a fall cone penetrometer and a torvane, while laboratory rainfall simulations were used to form experimental crusts. Dust emissions from non-crusted and crusted soils were measured and compared with a Portable In-Situ Wind Erosion Laboratory (PI-SWERL).</p><p>Our results show that crusts with sufficient strength to limit dust emissions form on bare Arenosols and Luvisols in the field, illustrating their potential impact on dust emissions. The laboratory rainfall simulations showed that stable crusts could be formed on these soils by 15 mm of rainfall, which is a common amount for single events during the rainy season in the Free State. The PI-SWERL experiments illustrated that the PM10 emission flux of such crusted soils is between 0.14% and 0.26% of that of a non-crusted Luvisol and Arenosol, respectively. The presence of loose sand on the crust acts as an abrader and can increase the emissions up to 4% and 8 % of the non-crusted dust flux. Overall, our study shows that crusts in the field are potentially strong enough to protect the soil surfaces against wind erosion during a phase of the cropping cycle when the soil surface in not protected by plants. These conclusions are not limited to the converted grasslands in the Free State. This indicates that applying farming techniques on croplands that protect crusts or enhance crust formation could be considered as soil management approach to minimize dust emission from dryland sandy soils.</p>

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