LOCATION RIOPERDIDO              NM

Established Series
Rev GWC-DAW
01/2015

RIOPERDIDO SERIES

The Rioperdido series consists of very deep, poorly drained soils that formed in silty alluvium over gypsiferous eolian sands. These nearly level soils are on drainageways. Slopes range from 0 to 3 percent. The mean annual precipitation is about 8 inches and the mean annual air temperature is about 67 degrees F.

TAXONOMIC CLASS: Coarse-gypseous, hypergypsic, thermic Oxyaquic Torrifluvents

TYPICAL PEDON: Rioperdido silty clay loam - rangeland. (Colors are for dry soil unless otherwise noted)

Ayz--0 to 5 inches (0 to 12 cm); pinkish gray (5YR 6/2) silty clay loam, reddish brown (2.5YR 4/3), moist; 32 percent clay; moderate medium subangular blocky structure; slightly hard, friable, very sticky, very plastic; many fine roots throughout; common fine dendritic tubular pores; gypsum, finely disseminated and carbonate, finely disseminated and salt, finely disseminated throughout; strongly effervescent, 17 percent calcium carbonate equivalent and 13 percent gypsum; slightly alkaline, pH 7.8; electrical conductivity 16.6 dS/m (mmhos/cm); strongly saline; gradual smooth boundary.

Cyyz1--5 to 14 inches (12 to 35 cm); pinkish gray (5YR 7/2) gypsiferous sandy loam, reddish brown (5YR 4/4), moist; 12 percent clay; massive; soft, very friable, slightly sticky, slightly plastic; common fine roots throughout; few fine dendritic tubular pores; gypsum, finely disseminated and carbonate, finely disseminated and salt, finely disseminated throughout; strongly effervescent, 6 percent calcium carbonate equivalent and 71 percent gypsum; slightly alkaline, pH 7.7; electrical conductivity 13.6 dS/m (mmhos/cm); moderately saline; clear smooth boundary.

Cyyz2--14 to 60 inches (35 to 152 cm); white (10YR 8/1) gypsiferous sand, gray (10YR 6/1), moist; 3 percent clay; massive; soft, very friable, nonsticky, nonplastic; common fine roots throughout; many fine interstitial pores; gypsum, finely disseminated and salt, finely disseminated and carbonate, finely disseminated throughout; slightly effervescent, 2 percent calcium carbonate equivalent and 71 percent gypsum; slightly alkaline, pH 7.7; electrical conductivity 9.2 dS/m (mmhos/cm); moderately saline.

TYPE LOCATION: Otero County, New Mexico. USGS Quad Lost River; approximately 7 miles north of the intersection of US Highway 70 and the White Sands National Monument entrance; 2,517 feet north and 1,425 feet west of the southeast corner of Section 36, Township 16 S, Range 7 E. Latitude: 32 degrees 52 minutes 47.80 seconds north, Longitude: 106 degrees 10 minutes 28.10 seconds west, NAD 83; UTM Easting: 390134 meters, UTM Northing: 3638590 meters. UTM zone 13.

RANGE IN CHARACTERISTICS:
Soil moisture: Typic aridic soil moisture regime based on precipitation. Moist in some part of the soil moisture control section during July - April. Driest during May and June. This soil has transitory internal free water and a fluctuating water table. Water table is at 0 to 20 inches in most years.

Mean annual soil temperature: 66 to 72 degrees F.

Particle-size control section (weighted average)
Clay content: 2 to 18 percent
Electrical conductivity: 8 to 16 dS/m
Percent gypsum: 40 to 90 percent

Ayz horizon
Hue: 2.5YR, 5YR, 7.5YR
Value: 4 to 6 dry, 3 to 5 moist
Chroma: 2 to 4, dry or moist
Texture: silt loam, silty clay loam
Clay: 20 to 36 percent
Calcium carbonate equivalent: 0 to 20 percent
Gypsum: 5 to 35 percent
Reaction: slightly alkaline to moderately alkaline
Salinity: moderately saline to strongly saline

Cyyz horizons
Hue: 5YR, 7.5YR, 10YR, N
Value: 4 to 8 dry, 3 to 7 moist
Chroma: 1 to 3, dry or moist
Texture: gypsiferous sand, gypsiferous loamy sand, gypsiferous sandy loam, gypsiferous silt loam
Clay: 2 to 18 percent
Calcium carbonate equivalent: 0 to 10 percent
Gypsum: 40 to 95 percent
Reaction: slightly alkaline to moderately alkaline
Salinity: moderately saline to strongly saline

COMPETING SERIES: There are no competing series.

GEOGRAPHIC SETTING: Rioperdido soils are on drainageways. Slope is 0 to 3 percent. These soils formed in gypsiferous lacustrine deposits. Elevation ranges from 3,980 to 4,040 feet. The mean annual precipitation is 8 to 12 inches. Precipitation falls mostly during the months of July through September. The mean annual air temperature is 64 to 70 degrees F. The frost-free period is 180 to 240 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Lark (NM), Astrobee (NM), Harses (NM) and Transformer (NM) soils. Lark soils are on vegetated dunes. Astrobee soils have pedogenic gypsum masses within 7 inches of the soil surface, Harses soils have a water table greater than 40 inches. Transformer soils have water tables are between 20 and 40 inches.

DRAINAGE AND PERMEABILITY: Poorly drained; low runoff; rapid permeability. Water table ranges from 0 to 20 inches during most years.

USE AND VEGETATION: The major uses are wildlife habitat, recreation and research activities. Native vegetation is inland saltgrass, salt cedar and iodine bush.

DISTRIBUTION AND EXTENT: South central New Mexico, limited to White Sands Missile Range and White Sands National Monument. MLRA 42, Rioperdido is of limited extent.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Phoenix, Arizona

SERIES ESTABLISHED: White Sands National Monument, Dona Ana County, New Mexico, 2014. The name Rioperdido is derived from the Spanish words "rio' and "perdido" which translate to river and lost.

REMARKS: Diagnostic horizon and features recognized in this pedon are:

Particle-size control section - the zone from 10 to 40 inches (Cyyz1 and Cyyz2 horizons)

Ochric epipedon - the zone from 0 to 5 inches (Ayz horizon)

Endosaturation - the zone from 0 to 60 inches (Ayz, Cyyz1, and Cyyz2 horizons)

Episaturation - the zone from 0 to 20 inches (Ayz, Cyyz1, and Cyyz2 horizons)

Classified according to Soil Taxonomy Second Edition, 1999; Keys to Soil Taxonomy, Twelfth Edition, 2014.

Revised for the correlation of White Sands Missile Range, New Mexico; October, 2014, NMS

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National Cooperative Soil Survey
U.S.A.