Soil Science & Analysis Flashcards
7 cards from real CFP practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Soil Science & Analysis flashcards as text
Bentonite clay is sometimes used in fish pond construction because it:
Answer: Has extremely low permeability when hydrated, reducing seepage
Bentonite is a swelling clay that expands when wet, creating an effective seal that dramatically reduces seepage in leaky ponds.
Which soil parameter is most predictive of whether a watershed will generate high or low sediment yields to streams?
Answer: Soil erodibility factor (K-factor) combined with slope and cover
The USLE/RUSLE K-factor, combined with slope length, steepness, and ground cover, best predicts sediment generation from a watershed.
In anaerobic pond sediments, which process primarily drives the release of phosphorus from iron-bound forms?
Answer: Reductive dissolution of iron oxyhydroxides releasing bound phosphorus
Under anaerobic (reducing) conditions, ferric iron (Fe³⁺) is reduced to ferrous iron (Fe²⁺), releasing phosphorus previously bound to iron oxyhydroxides.
A soil scientist reports a base saturation of 35% for a pond site soil. This measurement represents:
Answer: The proportion of CEC occupied by basic cations (Ca, Mg, K, Na)
Base saturation is the percentage of CEC sites occupied by basic cations (Ca²⁺, Mg²⁺, K⁺, Na⁺) rather than acidic cations (H⁺, Al³⁺).
Which method is the standard for determining soil particle size distribution in the United States?
Answer: Hydrometer method (ASTM D7928) combined with sieve analysis for coarse fractions
The hydrometer method measures sedimentation rates of fine particles (silt and clay), while sieve analysis covers sand and gravel fractions.
Muck soils (sapric Histosols) differ from peat soils (fibric Histosols) primarily in that muck soils have:
Answer: Greater decomposition of organic material with less recognizable plant tissue
Muck (sapric) soils are highly decomposed with little recognizable plant structure, while peat (fibric) retains identifiable plant fibers.
When interpreting a soil survey for watershed fisheries management, the hydrologic soil group (HSG) classification is used primarily to:
Answer: Predict surface runoff potential and infiltration capacity for stormwater modeling
HSG ratings (A through D) indicate infiltration rates and runoff potential, used in models like TR-55 to estimate peak flow and runoff volume.