1. 2018 Louisiana Soil Health and Cover Crop Conference
BMPs for Reducing Nutrient Runoff and Improving Water Quality in Louisiana Agricultural Watershed
Changyoon Jeong
Red River Research Station, LSU AgCenter

2. Human Health Climate Changes Food Security
Soil Management
Nutrient Management
Nutrient Loss Control
Diseases Control
Water Management

3. Best Management Practices (BMPs)
BMPs are practices to control the transmission of excessive nutrients from agricultural activities to watersheds.
Excessive nitrogen and phosphorus concentrations in water can accelerate algae and plant growth in streams and lakes, resulting in oxygen depletion or critically low dissolved oxygen levels - Hypoxia.
Sediment runoff reduction is one of the most important practices (an economic and environmental perspective). Based on volume, sediment is the largest pollutant of surface water in the nation.
The loss of nutrient-rich soil into rivers and streams is a financial loss. Conserve as much soil as possible can reduce the amount of fertilizers and other soil amendments to maintain adequate crop production.

4. BMPs Avoiding Controlling Trapping Nutrient management
Rate, Timing, Form, Methods
Controlling
Residue & Tillage Managements
Drainage Water Management
Trapping
Buffers
Wetland designed for nutrient removal

5. Filter strip 23 acres of Sugarcane field Runoff water to Filter Strip.
Outlet: 24 inch flumes
Inlet
68 ft
283 ft
2 % slope
Removed sediment from filter strip during 3 years study.
Pensacola Bahiagrass at a rate of 40 lbs per acre. A complete fertilizer ( ) was added at a rate of 180 lbs. per acre.

6. Hydrograph vs. concentration

7. Reduction Rate TSS and Nutrients Filter Strip.In
Out
% of reduction
(mg L-1)
TSS
1668
1251 25 TN
3.2
2.9
8.1 TP
0.33
0.28 15

8. On-Farm Tailwater Recovery System: Rice – Soybean Rotational Fields
Locations of the BMP site: NW of Kaplan, 30° 03' 12.82" N, 92° 14' 51.43" W ).

9. Irrigation well Rice Soybean Rice Site 1 Drainage : Pump
Site 9 Drainage Ditch
Site 2: Constructed wetland: Tailwater Recovery Reservoir
Site 6 Drainage Ditch
Site 3: Soybean
Irrigation well
Riser & well
Site 5: Soybean
Irrigation pipeline
Rice
Soybean
Site 4: Rice
Rice
Acres of surface water recycled from 4 sites.
Site 8 Drainage Ditch
Site 7: Rice

10. Average NO3-N concentration in tailwater irrigation site
Site No.
Description 1
Drainage A site + all other drainage 2
Constructed Wetland 3
Soybean West 4
Rice West 5
Soybean East 6
Drainage B off-site 80% 7
Rice East 8
Drainage C 80% off-site 9
Drainage D100% off-site
24% higher in closed system
17% higher
Rice Field
Rice Field

11. Average PO4-P concentration in tailwater irrigation site.
Site No.
Description 1
Drainage A site + all other drainage 2
Constructed Wetland 3
Soybean West 4
Rice West 5
Soybean East 6
Drainage B off-site 80% 7
Rice East 8
Drainage C 80% off-site 9
Drainage D100% off-site
75% higher in runoff
66 % reduction
24% higher
soybean
Constructed reservoir
rice

12. Fertilized Re-flooded August 2015 Clipped Rice Stubble
Site 7: Rice Harvested
Fertilized

13. Crop
Fertilized

14. Summary
The positive benefit of the BMPs on Nutrient loss and surface water quality from the filter strip & tailwater recovery irrigation system at the on-farm scale research.
Rice field water retained a significantly high concentration of N and P.
The constructed reservoir was significantly mitigated SRP and TP concentration.
Continuous BMP efforts are required to improve crop productivity and decrease NPS pollution.

15. Thank you ! Protect Our Watershed