Building
new topsoil:
The
most meaningful indicator of a healthy ecosystem and the long-term health
and well-being for a nation, is whether soil is being formed or lost. For
soil to be formed it must be living and healthy. Healthy soil requires a
groundcover of plants and plant litter that buffers temperatures, enhances
infiltration and decreases evaporation so the soil remains moist for
longer after precipitation. Soil structure is provided by gums and
polysaccharides produced by soil microbes. These sticky substances glue
together soil particles and minerals into small aggregates that are glued
together into larger aggregates called peds. When soil is well aggregated, the pores
(spaces) between the aggregates allow the soil to breathe and absorb
moisture quickly when it rains. An ongoing supply of energy in the
form of carbohydrates from actively growing plant roots and decomposing
litter is required so soil organisms can flourish and maintain or build
soil structure. Friable,
porous topsoil makes it easier for plants roots to grow and for soil
organisms to prosper, reinforcing the soil building process. Such soils
retain moisture longer which enhances the microbial activity that determines nutrient
availability for plants and reduces erosion.
Soil
organic matter:
Soil carbon and nitrogen are key
elements supporting ecosystem function and productivity. We are studying
the short- and long-term effects of different grazing and brush management
practices on these soil elements and soil structure.
Soil micro-fauna and
flora:
The abundance and composition of
soil microbes is an excellent indicator of soil health and function. We
are characterizing soil microfauna and microflora associated with
different soil series, plant communities and management practices
The 3 major soils we have on rangeland in our area are:
Loamy bottomlands. Relatively deep soils in toe-slope positions
Clay loam flats. Moderate depth soils in upland positions
Shallow clay slopes. Shallow clay soils on slopes or in upland positions
Loamy
bottomland
Clay-loam
Shallow-clay
