Institute of Ag Professionals

Transcription

1 Institute of Ag Professionals Proceedings of the 2006 Crop Pest Management Shortcourse & Minnesota Crop Production Retailers Association Trade Show Do not reproduce or redistribute without the written consent of author(s).

2 Remote Sensing for Nitrogen Fertilizer Management Dennis Francis USDA - ARS

3 Low N Use Efficiency for Corn Systems Due To Large, uniform doses ( lbs/ac) of N before active N uptake. To spatially variable landscapes. Worldwide NUE for cereal grains estimated at 33%. Representing a $15.9 billion annual loss of fertilizer N

4 N Removed in Grain Fertilizer N Applied N Uptake Grain Stover 70% 30%

5 Return to N 37 C-C Site-Years Across Iowa ( ) Return to N, $/acre Price Ratio Corn-Corn Rotation - Iowa N Rate, lb N/acre = $0.11 lb N : $2.20 bu 0.10 = $0.22 lb N : $2.20 bu 0.15 = $0.33 lb N : $2.20 bu 230 J.E. Sawyer, Iowa State Univ. ISU Agronomy Extension

6 Assume: 60 lb Return N/acre to legume N credit 111 C-S Site-Years Across Iowa ( ) Return to N, $/acre Corn-Soybean Rotation - Iowa Price Ratio N Rate, lb N/acre = $0.11 lb N : $2.20 bu 0.10 = $0.22 lb N : $2.20 bu 0.15 = $0.33 lb N : $2.20 bu J.E. Sawyer, Iowa State Univ. ISU Agronomy Extension

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8 Return to N 37 C-C Site-Years Across Iowa ( ) Return to N, $/acre Price Ratio Corn-Corn Rotation - Iowa N Rate, lb N/acre NUE = 43% = $0.11 lb N : $2.20 bu 0.10 = $0.22 lb N : $2.20 bu 0.15 = $0.33 lb N : $2.20 bu 230 NUE = 59% NUE = 54% J.E. Sawyer, Iowa State Univ. ISU Agronomy Extension

9 The Laws of Chemistry and Physics are against producers All nitrates (NO 3- ) are soluble in water Gravity moves water downward The soil is a lousy place to store N, but a reasonable place to store P

10 N Losses in Water? WHY Low N use efficiency Excess fertilizer N Spatial Variability Unaccounted N sources Failure to account for N credits Poor synchronization In-Season N Management Excess water (precipitation or irrigation)

11 Why Consider Remote Sensing??? Agronomic Considerations --- Soil-based approaches have not successfully addressed NUE problems. Need more temporal information! Economics Environment

12 Reasons to Consider VRT-Nitrogen Intuition Soils are inherently variable Crop yields vary within fields Plant population texture topography OM nutrients water Nutrients Water Disease / Insects Weeds

13 What Is It??? Remote Sensing - The act of measuring... sensing... from a distant location.

14 Satellites Aircraft Ground-based

15 Satellites Aircraft Clouds Timeliness Turn Around Resolution Ground-based Clouds Timeliness

16 Corner unit ON Irrigation Design Flaws

17 September 1, foot resolution

18 Soybean Color IR Hail damage Sprayer problems Cultivation in progress

19 5 July 06

20 Bare Soil Imagery Information that can be extracted or generated Erosion patterns Drainage patterns slope ph rooting depth Need for more tile lines Disrupted tile lines Fertility Organic matter content Relative nutrient status Management zone maps

21 Bare Soil After Planting

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23 EM-38 (electro-magnetic induction) Measures soil electrical conductivity

24 EM-38 (electro-magnetic induction) Measures soil electrical conductivity

25 +ph Veris Measures soil electrical conductivity

26 Computer Generated Management Zones Incorporating... Bare Soil Image Elevation Slope EM-38

27 Every Year is temperature rain wind

28 Use the Crop as a Bio-Indicator of N Status

29 Spectral Opportunities Biomass Reflectance (%) Photosynthesis Visible Near Infrared Living Vegetation Wavelength (nm)

30 Leaf Anatomy & Spectral Interaction Green Near IR Blue/Red Chlorophyll Lower Epidermis Stoma Air Space Palisade Cells Spongy Mesophyll

31 Reflectance (%) Healthy Plant Stressed Plant Bare Soil Wavelength (nm)

32 Photosynthesis Chlorophyll Biomass Vegetation Index Sufficiency Index

33 95% Sufficiency Index GDD vs Relative SPAD 110 Yield Relative SPAD lbs N/ac Translate into fertilizer N recommendation GDD

34 SPAD meter readings and active sensor data are highly correlated.... Sensor But They represent different parts of the plant! SPAD Uppermost Expanded Leaf

35 Sensors to Monitor Crop VIGOR Vegetation Indices

36 Sensor Features Generate their own light Operate in day or night Low power requirement Collect about 40,000 readings per second Record data at 10 times per second

37 What we know about corn??? Early season stresses can reduce yield potential

38 When? How much? How much early? In season? N uptake Sensor based In-season N Early N Planting V6 V9 Tasseling

39 Potential for remediation? very high V10 high gone

40 Challenge : Manage soil N availability so the crop will be responsive to N status (biomass and chlorophyll) at ~V without reducing yield potential. N Status Yield Potential ~V10

41 What does a Healthy Crop Look Like??

42 Field Calibration Reference Reference Direction of travel Sufficiency Index Reference Field Reference

43 Strategy # 1 Maize Apply 50-75% of the recommended fertilizer nitrogen pre-planting or sidedress Uniform or Variable rate Be ready to correct N deficiencies

44 Irrigated Corn What will work for producers? Total N Uptake (kg/ha) % N Uptake Dry Matter 0 to 50% Dry Matter (Mg/ha) Starter Calendar Day

45 Strategy # 2 Maize Apply ~20% of the expected fertilizer nitrogen pre-planting or at planting Variable rate at V8-V10 Active Crop Canopy Sensor

46 Irrigated Corn What will work for producers? Total N Uptake (kg/ha) ~20% N Uptake Dry Matter 50 to 80% Dry Matter (Mg/ha) Starter Calendar Day

47 High Clearance In-Season Applicator GreenSeeker GPS Receiver Fertilizer Nozzles Active Sensor

48 Crop Circle Sensor Holland Scientific

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50 Syngenta Farm, York, NE 225 lbs N/ac preplant (reference) 75 lbs N/ac preplant 0 lbs N/ac preplant (check) Three 12-row strips Three preplant N rates

51 June 27, lbs N/ac preplant (reference) 75 lbs N/ac preplant Sensing and N application 0 lbs N/ac preplant (check) July 18, 2006

52 225 lbs N/ac preplant (reference) 75 lbs N/ac preplant 0 lbs N/ac preplant (check)

53 July 5, 2006 V15 (Sensor applied) Base 40lbs N/ac 80lbs N/ac Alternating 8 row strips Calibration Plots

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55 N Sensor (Yara, formerly Hydro Agri) Cab Top Mounted DGPS or GPS (optional) Irradiance Sensor PC S1 S2 Left Sensors Right Sensors In Cab Section Touch Screen Card Drive Spreader Controller

56 ~ 13 m 2 Wavebands = red and NIR Indices =??? Algorithm =???

57 Ramped Calibration Strip

58 Reality : N status is spatially variable How to incorporate spatial variability into the Ramped Calibration Strip concept? Controller

59 June 27, 2006 Previous crop: alfalfa Base rates: 2 Ramps applied: V5 ~June 10

60 July 18, 2006 Where are the ramps? 15, 30, 45, 60, 75, 90, 115 lb N/acre

61 June 27, 2006 Non-Ramped Calibration Plots Ramped N V3 Blanket 80 lbs N/ac Ramps 0, 20, 40, 60, 80, 100

62 July 18, 2006 Non-Ramped Calibration Plots Where are the ramps?

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64 Decision Aid Development Vegetation Index Calibration Yield map data Predicted In-Season optimum yield Soil Map Growth stage N Management Algorithm OM Variable-Rate Recommendation

65 Dennis Francis