The RC&D area has rich diversity of vegetation due to the great range of elevation and precipitation. Some of the natural communities of vegetation include Mojave Desert Scrub, Joshua tree Woodland, Chaparral, Mountain Riparian forest and scrub, Alpine habitats, Mojave Creosote Bush scrub just to name a few.

English and Spanish are the primary languages with at least 54 different languages in all spoken within the RC&D area. There are eight Native American reservations and 13 tribal groups or language groups within the area. All of these people have religious and traditional use sites within the boundaries of the RC&D area.

In the southern portion of the Lahontan Region is the Mojave River watershed. The Mojave River, which is sometimes referred to as “backwards” river flows away from the ocean, flows primarily underground, surfacing only in three locations along its’ river course. Historically, agriculture had been the highest demand for water for the Mojave River watershed; however, in recent years, urban water usage has increased. It is predicted that urban water use will exceed agriculture demand by the year 2015. This watershed has been in an overdraft condition since the early 1950’s. It is estimated that the average annual overdraft in groundwater basins in the Mojave River area is approximately 65,000 to 70,000 acre-feet. This estimate is projected to increase to about 93,000 acre-feet by the year 2015 if water conservation measures are not implemented. A regional water management plan has been developed for this area. In addition, the desert area of San Bernardino County has had its water adjudicated with water users pumping over 10 acre-feet per year required to reduce their stipulated production by 20 percent. This adjudication affects both agriculture and urban water users within the adjudicated area.

The Colorado Basin Region is located in the southern half of San Bernardino County, stretching to the Colorado River. Various Indian Tribes (Chemehuevi, Fort Mojave, and the Colorado River Indian Tribes) rely heavily upon the Colorado River to provide water for irrigation and potable water. Concern has risen over the discovery of perchlorates and the possible affects this contaminate may have on the health of the users of this water. Some tribes have initiated plans to lease some of their water in hopes of generating income to assist them in improving their reservations.

These soils are generally well drained, but those in wet meadows are somewhat poorly drained. The southeastern Great Basin area is located in the northern most area of the RC&D. The slopes are steep mountains, moderate to steep hills, gently to moderately sloping volcanic flows and alluvial fans, and nearly level fold plains, basin floors, and terraces. The soils of the hills and mountains are usually shallow and have loamy textures. On the alluvial fans, flood plains, basin floors and terraces, the soils are deep and have sandy and loamy textures. The soils are generally well drained but are poorly drained on basin and lacustrine deposits.

The Mojave Desert, which includes a small area of the Sonoran Desert in the southern part, is located mainly in the central part of the RC&D district extending to the southern part. For some isolated mountains and hills, the slopes are steep to very steep. It is nearly level for the lake beds and basin floors. The alluvial fans are moderately sloping to steep. The soils are deep and loamy in the alluvial fans. The hills and mountains are usually shallow and have loamy textures. Most of the soils are well drained except for the lake beds and basin floors.

Three active faults intersect this area of Kern County and Los Angeles County; they are the Garlock, Sierra, and San Andreas Faults. The San Andreas runs east and west along the southern portion of the Los Angeles County section of the Mojave Desert-Mountain Resource Conservation and Development area. This fault has experienced earthquakes of magnitude 8 and higher. The Garlock is an offshoot from the San Andreas Fault and is generally assumed to be active and capable of producing earthquakes of at least magnitude 8. The time of the last great earthquake on the Garlock fault is not known. The recurrence interval is not known. The volcanic activity in the Long Valley-Mono craters (Mammoth Lakes area) has been quiet for approximately 600 years. However, seismic activity in this area has been one of the most active in the state. Most of the earthquakes are swarms with small magnitudes related to magma movement.

Four of the nine geomorphic provinces in California are represented in the area: the Mojave Desert, the basin and range, the Sierra Nevada, and Transverse Ranges. The granitically stable Sierra Nevadas rise to 10,000 feet above mean sea level (MSL). The northwest to southeast trending valley and ridge structure of the basin and range province is determined by faults along the valley edges. The lack of water and the quality of the water that is present impair the Mojave Desert. The transverse Ranges are still being lifted up and thus have a high erosion rate accompanied by a high landslide and debris flow potential.

The decomposed granites of the Sierra Nevada pose an erosion problem with dry gravel. The low nutrient level makes re-vegetation after any disturbance particularly difficult.