CF Watershed & Soil Conservation Flashcards

What is the primary purpose of a best management practice (BMP) related to stream crossings in forestry operations?

Answer: Prevent sediment delivery and protect water quality at stream crossings

Stream crossing BMPs such as properly sized culverts and bridging prevent sediment from entering streams during timber harvesting operations.

Which soil property most directly determines a site's susceptibility to compaction from heavy logging equipment?

Answer: Soil texture and moisture content

Fine-textured soils (clay and silt) at high moisture content are most vulnerable to compaction because water reduces inter-particle friction and pore space collapses under load.

What is the function of a broad-based dip (BBD) on a forest road?

Answer: Divert surface water off the road surface before it gains erosive velocity

Broad-based dips are drainage structures built into forest roads that interrupt surface water flow and redirect it into stable vegetated areas before it erodes the roadbed.

Which equation is most widely used in the US to estimate annual soil erosion from forest and agricultural land?

Answer: Universal Soil Loss Equation (USLE)

The USLE estimates average annual soil loss as a function of rainfall erosivity, soil erodibility, slope length/steepness, cover management, and support practices.

A riparian buffer strip in a harvested watershed primarily reduces which water quality concern?

Answer: Sediment delivery and nutrient loading to streams

Riparian buffers filter overland flow, trapping sediment and retaining nutrients before they reach stream channels.

What does 'peak flow' refer to in watershed hydrology?

Answer: The maximum discharge rate in a stream following a storm event

Peak flow is the highest flow rate observed in a stream during or immediately after a precipitation event and is critical for flood prediction and culvert sizing.