LOCATION EL INDIO                PR

Established Series
ASR/SRT/RBT
11/2021

EL INDIO SERIES

MLRA(s): 273
MLRA Soil Survey Regional Office (SSRO) Responsible: Raleigh, North Carolina
Depth Class: Very deep
Drainage Class: Poorly drained
Saturated Hydraulic Conductivity: High
Parent Material: Calcareous sandy marine deposits
Slope: 0 to 2 percent
Mean Annual Air Temperature: 26 degrees C. (79 degrees F.)
Mean Annual Precipitation: 1041 millimeters (41 inches)

TAXONOMIC CLASS: Carbonatic, isohyperthermic Typic Psammaquents

TYPICAL PEDON: El Indio sand--wildlife habitat (Colors are for moist soil).

A--0 to 15 centimeters (0 to 6 inches); 90 percent very dark grayish brown (10YR 3/2) and 10 percent very pale brown (10YR 8/2) sand; single grain; loose; nonsticky, nonplastic; about 5 percent by volume 2 to 75-millimeter shell fragments; moderately alkaline; violently effervescent; clear smooth boundary.

AC--15 to 36 centimeters (6 to 14 inches); 50 percent very dark grayish brown (10YR 3/2) and 50 percent very pale brown (10YR 8/2) sand; single grain; loose; nonsticky, nonplastic; about 10 percent by volume 2 to 75-millimeter shell fragments; moderately alkaline; violently effervescent; clear smooth boundary.

Cg1--36 to 56 centimeters (14 to 22 inches); 50 percent very dark grayish brown (10YR 3/2) and 50 percent very pale brown (10YR 8/2) shelly coarse sand; single grain; loose; nonsticky, nonplastic; 10 percent fine, medium, and coarse yellowish red (5YR 4/6), moist, masses of oxidized iron; 25 percent 2 to 75-millimeter shell fragments; moderately alkaline; violently effervescent; clear smooth boundary.

Cg2--56 to 122 centimeters (22 to 48 inches); 90 percent gray (2.5Y 5/1) and 10 percent very pale brown (10YR 8/2) shelly coarse sand; clear, smooth boundary; single grain; loose; nonsticky, nonplastic; 25 percent 2 to 75-millimeter shell fragments; moderately alkaline; violently effervescent; clear smooth boundary.

Cg3--122 to 203 centimeters (48 to 80 inches); 90 percent dark grayish brown (2.5Y 4/2) and 10 percent very pale brown (10YR 8/2) shelly coarse sandy loam; massive; very friable; 25 percent 2 to 75-millimeter shell fragments; moderately alkaline; violently effervescent.

TYPE LOCATION: Salinas municipality, Puerto Rico. Punta Colchones. Jobos Bay National Estuarine Research Reserve grounds. 1 mile east from end of camino El Indio at Las Mareas community at bearing 86.86 degrees. Approximately 1.74 miles southwest of JBNERR main building (PR-705, Central Aguirre Historic District, Salinas, 00784) at bearing 205.02 degrees. Access to the site is best and easiest by boat. Latitude: 17 degrees 56 minutes 1.20 seconds north and Longitude: 66 degrees 14 minutes 1.60 seconds west WGS 84.

RANGE IN CHARACTERISTICS:
Solum thickness: 8 to 36 centimeters (3 to 14 inches). The thickness of sand is more than 60 inches
Depth to Seasonally High-Water Table: 30 to 50 centimeters (12 to 20 inches)
Depth to Redoximorphic features: 3 to 36 centimeters (1 to 14 inches) and occur as concentrations and are disguised by the light color of the materials
Soil Reaction: Slightly alkaline to moderately alkaline
Depth to bedrock: more than 6 feet
Rock fragments: 0 to 30 percent, by volume, throughout consisting of coral and shell fragments increasing with depth
Salinity: 32 to 36 ppt

RANGE OF INDIVIDUAL HORIZONS:
A horizon:
Color--hue of 10YR or 2.5Y, value of 3 to 8, and chroma of 2 or 3.
Texture--sand or coarse sand.

AC horizon: (sometimes this horizon can be at the soil surfacedue to coastal erosion)
Color--hue of 10YR or 2.5Y, value of 3 to 8, and chroma of 1 or 3.
Texture--sand or coarse sand.

Upper part of the C horizon:
Color--hue of 10YR 2.5Y or 7.5YR, value of 3 to 8, and chroma of 1 to 3. Few distinct iron oxidations in the matrix with high value and chroma. Texture--coarse sand, sand or its gravelly (shelly) counterparts.

Lower part of the C horizon:
Color--hue of 10YR or 2.5Y, value of 4 to 8, and chroma of 1 or 2.
Few distinct iron oxidations in the matrix with high value and chroma. Texture--coarse sandy loam to coarse sand and its gravelly (shelly) counterparts.

COMPETING SERIES: This is the Atolladero series.
Atolladero soils-have thin organic surface horizons, do not have A or AC horizons, allow 5Y and 10Y colors and occur in the Humid Coastal Plain of Puerto Rico.

GEOGRAPHIC SETTING:
Landscape: Semiarid coastal plain in southern Puerto Rico (MLRA 273).
Landform: Coastal beaches protected by the barrier reef.
Parent Material: Calcareous sandy marine deposits
Mean Annual Air Temperature: 22 to 31 degrees C. (71 to 88 degrees F.)
Mean Annual Precipitation: 508 to 1,600 millimeters (20 to 63 inches)

GEOGRAPHICALLY ASSOCIATED SOILS:
Jaucas soils are much deeper to water tables and occur on considerably higher positions on the landscape.
Manglillo soils have thick organic horizons and occur slightly lower on the landscape.
Mar Caribe soils are moderately deep to limestone bedrock and occur on slightly lower landscape positions.
Mar Negro soils have thick organic horizons, have subaqueous drainage and occur on slightly lower landscape positions.
San Felipe soils have thick organic horizons, sulfidic soil materials, and occur on slightly lower landscape positions.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage class: Poorly drained
Saturated Hydraulic Conductivity: High

USE AND VEGETATION:
Major Uses: Recreation area and wildlife habitat.
Dominant vegetation: Black mangroove, batis, majaguilla and other halophitic herbaceous plants.

SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: Raleigh, North Carolina.

DISTRIBUTION AND EXTENT: Southern coastal plains of Puerto Rico. This series is of small extent.

SERIES ESTABLISHED: Salinas Municipality, Puerto Rico; 2021. The name is from Camino El Indio on Las Mareas community, where it was originally recognized.

REMARKS:
Diagnostic horizons and features recognized in this pedon:

1. Ochric epipedon: the zone from 0 to 36 centimeters (0 to 14 inches; A and AC horizons).
2. Psammentic feature: sandy textures throughout the particle-size control section-the zone from 25 to 100 centimeters (10 to 40 inches (Cg1 and Cg2 horizons).
3. Redox concentrations and aquic conditions: starting at 36 centimeters (14 inches) and continuing throughout the profile, concentrations are mainly oxidized iron masses.

These soils were formerly included in the Coastal beach, Meros sand or miscellaneous land type mapunits.

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National Cooperative Soil Survey
U.S.A.