Albuquerque's Environmental Story

Educating For a Sustainable Community

TERRAIN - Smooth but fairly steep slopes (to 10% and above) near mountain front, grading westward to a gently undulating surface with slopes of 3-5%, and relief tens of feet near arroyos.

CLIMATE AND AIR QUALITY - Descriptions: see description of "Volcanic" unit. Comments; like "Volcanic" unit, except that urbanized areas have major hydrocarbon, carbon monoxide, and photochemical oxidation air quality problems.

GEOLOGY - A series of coalescing alluvial fans (Bajada) composed of sands and gravel and younger formations, deposited in a down-dropped block (the Rio Grande Rift). Resources and Hazards: resources are limited to sand and gravel; hazards are flash flooding, mud flows, potential earth movements along fault scarps, and, in places, poor compaction.

SOILS - Association: Tijeras-Embudo. Description: deep, well-drained gravelly sandy loams of alluvial fans, some clay in subsoil. Notable Characteristics: rapid percolation rate and moderate shrink-swell; otherwise few engineering problems, generally suitable for urban development.

HYDROLOGY - Mountain channels feed into many arroyos which spread over the fan surface. Mountain runoff which reaches alluvial fans generally percolates into the porous material; this is a major source of recharge to the regional ground water supply. Summer storms here or in mountains may cause flash floods, now partly controlled by diversion ditches. Ground water found 300-1,000 feet (91-305 m.) beneath the surface, generally in considerable amounts in sediments of Santa Fe Formation; many municipal wells are found here which obtain water of acceptable to good quality.

VEGETATION - Zone: Upper Sonora. Indicator Species: mostly mid and short grasses; some little soapweed (yucca), almost no native species in urbanized areas. Productivity, Sensitivity: moderate grazing capacity; most disturbance, other than directly man-related results from overgrazing or drought. Otherwise, fans are not overly sensitive to disturbance.

WILDLIFE - Indicator Species: many burrowing animals such as ground squirrel, prairie dog, field mice. Also hawks, quail, roadrunner, and numerous lizards. Value: undisturbed areas provide food and cover for grassland rodents and reptiles. Disturbed areas are of little value. Periodic storm run-off provides additional moisture; resultant scrubby vegetation provides added cover for wildlife.