Terrestrial Vegetation & Soils
Generating over 99.9% of the Earth's biomass, plants are the primary producers of life on our planet. Vegetation is the biological foundation of terrestrial ecosystems and is highly influenced by environmental factors, such as soil texture, depth, and landform type. Especially as they relate to water, these influences are magnified at local scales in the Sonoran and Chihuahuan deserts and Apache Highlands ecoregions.
Vegetation manipulation is a primary component of most biological resource management. Knowing about the status and trends of vegetation and soils can help park managers to modify vegetation to achieve goals related to wildlife management (via habitat manipulation), fire management (via fuels modification) and plant ecology (via direct or indirect changes to plant interactions). Accounting for soil dynamics provides information on management issues and stressors that may have long-term consequences for terrestrial ecosystem structure and function.
Measurements and Objectives
Monitored measures include:
- Foliar cover of perennial plant species and lifeforms
- Soil cover by substrate type
- Biological soil crust cover
- Average soil aggregate stability
- Bulk density of soils
The objectives of this monitoring are to determine the status and long-term trends in:
- Vegetative cover of common native and non-native perennial, and non-native annual plant species
- Frequency of uncommon native perennials (<10% cover), all annual lifeforms, and all non-native species
- Density of columnar cacti and ocotillo
- Soil cover type
- Cover and frequency of biological soil crusts
- Surface soil aggregate stability
- Soil bulk density
For more information, contact Andy Hubbard, Program Manager, Sonoran Desert Network; Sarah Studd, Vegetation Ecologist, Sonoran Desert Network; or Cheryl McIntyre, Physical Scientist, Chihuahuan Desert Network.