B.S.F. or B.Sc.F. Bachelor of Science in Forestry Forest Hydrology and Watershed Management 2 — Questions and Answers
Question 1: Evapotranspiration (ET) in a forested watershed is the combined loss of water through:
- Streamflow and groundwater recharge
- Transpiration by plants and evaporation from surfaces (Correct answer)
- Infiltration and percolation
- Snowmelt and overland flow
Correct answer: Transpiration by plants and evaporation from surfaces
ET combines transpiration through leaf stomata and direct evaporation from soil, litter, and canopy surfaces into the total water vapor flux to the atmosphere.
Question 2: Which soil property most directly controls the rate of infiltration?
- Soil color
- Bulk density and porosity (Correct answer)
- Organic matter color
- Cation exchange capacity
Correct answer: Bulk density and porosity
Bulk density and porosity determine pore space available for water entry; compacted soils have low porosity and reduced infiltration rates.
Question 3: The concept of 'peak flow' in watershed hydrology refers to:
- The average annual streamflow volume
- The maximum instantaneous discharge during a storm event (Correct answer)
- Baseflow sustained by groundwater between storms
- The flow needed to transport bedload sediment
Correct answer: The maximum instantaneous discharge during a storm event
Peak flow is the highest discharge rate recorded during a storm hydrograph and is critical for flood prediction and infrastructure design.
Question 4: Forest harvesting generally causes streamflow to:
- Decrease due to reduced precipitation interception
- Increase due to reduced evapotranspiration (Correct answer)
- Remain unchanged if buffer strips are maintained
- Decrease due to increased soil compaction
Correct answer: Increase due to reduced evapotranspiration
Removing trees reduces evapotranspiration, so more precipitation reaches the stream, increasing annual water yield and peak flows.
Question 5: Best Management Practices (BMPs) in US forestry are primarily designed to:
- Maximize timber yield per acre
- Protect water quality during and after forest operations (Correct answer)
- Reduce wildfire ignition risk
- Improve wildlife habitat connectivity
Correct answer: Protect water quality during and after forest operations
Forestry BMPs are voluntary or regulatory guidelines for logging roads, stream crossings, and harvest operations specifically to minimize water quality impacts.
Question 6: What is 'baseflow' in a stream?
- The stormflow peak immediately after rainfall
- Sustained low-level streamflow between storms, fed by groundwater discharge (Correct answer)
- The minimum engineered flow for hydropower generation
- Overland flow from impervious surfaces
Correct answer: Sustained low-level streamflow between storms, fed by groundwater discharge
Baseflow is the portion of streamflow derived from groundwater (shallow aquifer) discharge that sustains streams during dry periods.
B.S.F. or B.Sc.F. Bachelor of Science in Forestry Forest Hydrology and Watershed Management 2
Evapotranspiration (ET) in a forested watershed is the combined loss of water through: