An Integrated Approach to Foster Science-Based Management of Agricultural Drainage

Channels in the Western Lake Erie Basin

USDA Project Director’s Meeting

October 12, 2016

The Need for Drainage

Optimized for a Single Purpose

Can we design and implement practices in ditches and headwater streams that satisfy the need for drainage, but also

reduce downstream impacts?

Traditional Trapezoidal Ditch

Erosion Deposition

Common Responses to Channelization

A. Trapezoidal Channel

Original Channel

Trapezoidal Channel

Signifies Human Management

B. Two-Stage Channel (Natural)

Depositional Material

C. Two-Stage Channel (Constructed) E. Self-Forming Channel (1-year old) D. Self-Forming Channel (1-month old)

Channel Design and

Maintenance Approaches

Channel Design Guidance

How will our project help inform and advance the management of drainage channels in the WLEB?

1. Quantitatively measure sediment and nutrient retention within self-forming channel benches and assess their spatiotemporal variability (Research Objective)2. Assess ecosystem services provided by two-stage and self forming channels by evaluating soil microbiota biodiversity and functionality (Research Objective)3. Identify factors that affect adoption of alternative channel designs (Research and Extension Objective)4. Target implementation of alternative channel designs in the Western Lake Erie Basin (Research and Extension Objective)5.Conduct educational and extension activities to enhance student and stakeholder knowledge of innovative channel best management practices that improve water quality (Education and Extension Objective)

Objective 1

Goal: Assess spatiotemporal variability of sediment and nutrients stored in floodplain benches• Factors• Ecoregion• Bench Position• Depth• Seasonal• Annual

• Soil physical and chemical properties– Bulk density– Particle size analysis– pH– Electrical conductivity– Total C, N, P– P fractionation– NO3-, NH4+– Soil microbial biomass C,

N, P

Experimental Design: Ecoregions

• Maumee Lake Plains - poorly drained, fertile soils developed from clayey lake deposits that were historically Elm-Ash swamps and beech forests;

• Oak Openings - belt of wooded sand dunes and paleobeach ridges amongst broad plains with well-drained sandy soils;

• Paulding Plains - clayey lacustrine sediments and very poorly drained, illitic soils;• Clayey, High Lime Till Plains - surface of clayey till with well-defined moraines and

intervening, flat ground moraine;• Lake Country - Pitted moraine areas characterized by pothole lakes, marshes, and bogs

adjacent to well-drained kames and end moraines.

Experimental Design: Bench Position

and Depth

US

NCDS

NB

0-5 cm5-20 cm

20-35 cm35-50 cmUpstream

Downstream

Near Bank

Near Channel

0-5 cm

5-20 cm

20-35 cm

3 Seasons:Late Spring/Early SummerLate Summer/Early AutumnLate Winter/Early Spring

Two Years – 2012, 2013

Carbon and Nitrogen Retention

2. Assess ecosystem services provided by two-stage and self forming channels by evaluating soil microbiota biodiversity and functionality (Research Objective)

• Measure soil microbial biomass – C, N, and P• Diversity and community structure – Illumina-

sequencing• Functional potential – Geochip functional gene array

platform• Expected outcomes – more holistic definition of

potential ecosystem services

3. Identify factors that affect adoption of alternative channel designs (Research and Extension Objective)

• Phase I – telephone interviews with key decision makers to determine attitudes towards practices

• Phase II – landowner survey to determine willingness to adopt

• Phase III – field experiment to determine how expert involvement with landowners/decision makers influences adoption

• Expected outcomes – knowledge of factors that influence decisions

Phase 3: Field Experiment• Role of information/education vs. stakeholder

participation and involvement in a collaborative process

• Hypothesis: Stakeholder engagement in developing information will lead to improved results for two reasons:– Engaging in the process yields buy-in to support the

results– Including stakeholders yields a better product –

information developed is more useful to stakeholders in their decision making

Experimental Design

Experimental Design

Experimental Design

Pre- and Post-Survey Scores Across Treatments

Discussion• The information appeared to be more

important than engaging stakeholders in a collaborative process

• Results highlight:– Importance of making educational presentations

(~20% had heard about two-stage ditches)

5. Conduct educational and extension activities to enhance student and stakeholder knowledge of innovative channel best management practices that improve water quality (Education and Extension Objective)

• Conferences• Coursework • Professional Journals• STEM Workshops– Ridgemont HS