REVISED UNIVERSAL SOIL LOSS EQUATION-Version 2

UNIT 1

OBJECTIVES

UNIT 2

OVERVIEW OF EROSION

EROSION

DETACHMENT

DETACHMENT

DEPOSITION

DEPOSITION

TYPES OF EROSION

DEFINITIONS

DEFINITIONS

DEFINITIONS

DEFINITIONS

DEFINITIONS

LOCAL DEPOSITION

Credit for Deposition

SEDIMENT CHARACTERISTICS

EROSION IS A CONCERN

WHERE EROSION CAN BE A PROBLEM

EROSION PREDICTION AS A TOOL

EROSION PREDICTION AS A TOOL

PLANNING VARIABLES

UNIT 3

OVERVIEW OF RUSLE2
(Revised Universal Soil Loss Equation-Version 2)

Landscape

FACTORS AFFECTING INTERILL-RILL EROSION

RUSLE2 FACTORS
Daily Soil Loss
a = r k l s c p

RUSLE FACTORS
(Sediment Production)

RUSLE FACTORS

RUSLE FACTORS

Slide 33

Slide 34

How Deposition at a Grass Strip Affects Sediment Characteristics

RUSLE2 BACKGROUND

RUSLE2 APPLICATIONS

SUMMARY

Unit 4

RUSLE2 Factors

EROSIVITY

EROSIVITY - R

Erosivity Varies During Year

10 yr EI

Reduction by Ponding

SOIL ERODIBILITY - K

SOIL ERODIBILITY - K

Time Variable K

Time Variable K

TOPOGRAPHY

Hillslope Shape

Overland Flow Slope Length

Slope Length for Eroding Portion of Slope

Slide 54

Slope Length for Concave Slope

Rule of Thumb for Deposition Beginning on Concave Slopes

Slope Length for Concave:Convex Slope

Slide 58

Basic Principles

Detachment Proportional to Slope Length Factor

Slope Length Effects

Detachment Proportional to Slope Steepness Factor

Effect of Slope Shape on Erosion

Land Use

Cover-Management

Supporting Practices

Cover-Management Subfactors

Cover-Management Effects

Canopy

Effective Fall Height

Ground Cover

Ground Cover Effect

Ground Cover

Interaction of Ground Cover and Canopy

Random Roughness

Random Roughness

Ridges

Dead Biomass Pools

Decomposition of Dead Biomass

Below ground biomass

Effect of Below Ground Biomass

Soil Consolidation

Width of Disturbance

Antecedent Soil Moisture (NWRR)

Supporting Practices

Contouring/Cross Slope Farming

Contouring/Cross Slope Farming (continued)

Critical Slope Length

Buffer/Filter Strips

Rotational Strip Cropping

Terraces

Slide 92

Deposition in Terraces

Diversions

Impoundments (Small sediment control basins)

Sequencing of Hydraulic Elements

Benefit of Deposition

Subsurface Drainage Systems

Unit 5
Databases

Profiles

Worksheets

Concept of Core Database

Critical RUSLE2 Rules

Climate

EI Distribution

Soil

Management

Operations

Operation Effects

Operation Effects (cont)

Operation Effects (cont)

Operation Effects (cont)

Operation Effects (cont)

Operation Effects (cont)

Vegetation

Yield-Residue Relationship

Yield-Retardance Relationship

Retardance for Up and Downhill

Residue

Senescence

Contouring/Cross Slope Farming

Strips/Barriers

Hydraulic Elements and Their Sequence

System of Hydraulic Elements

Subsurface Drainage Systems

UNIT 6

LIMITS OF APPLICABILITY

APPLICABLE PROCESSES

Applicable Land Uses

Cropland Applications

MOST APPLICABLE GEOGRAPHIC REGIONS

APPLICABLE SOILS

APPLICABLE TOPOGRAPHY

APPLICABLE TOPOGRAPHY

UNCERTAINTY

Significant Change

TEMPORAL APPLICABILITY

Sensitivity

Examples of Sensitivity

Examples of Sensitivity (cont)

Examples of Sensitivity (cont)

SUMMARY