Yield Mapping More than just pretty pictures!

Transcription

1 SOUTH AFRICAN SUGARCANE INDUSTRY AGRONOMISTS ASSOCIATION Annual Symposium 25 th October 2017 Yield Mapping More than just pretty pictures! Alasdair Harris The Technology Group Tongaat Hulett

2 Where does yield mapping fit in?

3 Where does yield mapping fit in?

4 Where does yield mapping fit in?

5 Where does yield mapping fit in?

6 Where does yield mapping fit in?

7 What we ve done so far Proof of variability justification for starting the precision ag journey Methods GPS areas vs bundle locations Soils investigation Future Work Quality mapping Compare yield variation over time

8 Variation in Fertilizer costs Average 50 = R4038/ha Average 5a = R2423/ha Average 5b = R4818/ha Average 5c = R10345/ha Average 5d = R3122/ha Average 5e = R5052/ha Average i = R5152/ha Mean (R/ha) Minimum Difference (R/ha) -1, Maximum Difference (R/ha) 2, Range (R/ha) 3,971.65

9 Remote Sensing And / Or Yield Mapping? Remote sensing is the science of obtaining information about objects or areas from a distance, typically from aircraft or satellites - A yield map is a spatially referenced, graphical representation of crop yield for a defined area - t%20handout%20yield%20monitoring%20and%20mapping.pdf *NDVI Normalized difference vegetation index essentially it indicates growth vigour based on the greenness of the crop

10 Remote Sensing And / Or Yield Mapping? Remote sensing assist proactive farm management Assists in identifying homogenous zones (growth vigour, soil characteristics etc) Quantifies the area and location of each zone within a field which assists in guiding infield investigations to understand the root cause of the variation The difference between knowing there is variation and actually being able to quantify it and monitor crop response to changes in management over time

11 Remote Sensing And / Or Yield Mapping? Remote sensing assist proactive farm management Assists in identifying homogenous zones (growth vigour, soil characteristics etc) Quantifies the area and location of each zone within a field which assists in guiding infield investigations to understand the root cause of the variation Remote sensing is the interim report allowing for possible corrective actions or at the very least provides guidance to your yield estimates

12 Remote Sensing And / Or Yield Mapping? A yield map represents the net effect of all agro-inputs (climate, soils, management ) Year-on-year yield mapping of the same fields will be key to understanding the impact (positive or negative) of varying management techniques based on homogenous zone mapping.as will any changes to the homogenous zones over time Yield mapping Practical Methods Manual GPS mapping of cutter tasks research only Stack location mapping Load sensors on cane loaders Pressure or stereoscopic optical sensors on mechanical harvesters UAV biomass estimations LIDAR (Light Detection and Ranging) Dr. Peter Tweddle..

13 You can see the variation but how do you manage it?

14 Stalk Length A good proxy for yield? Lidar Canopy Height Map

15 Stalk length is an integral breeding selection criteria with moderate correlations to yield heritability, (Wijesuriya et al., 1993) Stalk Length A good proxy for yield? Stalk height showed significant correlation with stalk number, stalk diameter (Silva et al., 2008) emphasis during selection can be placed on responsive traits such as stalk number and stalk height. (Zhou, 2009). number of stalks and stalk height contributed most to cane yield. (Mbuma et al., 2017)

16 Mechanical Harvester Yield Maps Images courtesy of John Dighton of John Deere 23 rd October 2017

17 Mechanical Harvester Yield Maps Harvest time maps are useful but be default don t allow you to plan ahead. Lidar (when its cheaper) has the potential to: Optimize mechanical harvester operations by presetting forward speed, topping height and fan speed and allowing the operator to adjust a single control which operates the machine as a percent of the optimized settings. Auto-defined manual cutter tasks to ensure even bundle masses Trial work Average canopy height per replicated treatment which would allow a researcher to track growth response by treatment over time rather than just harvest tonnage.

18 Intra-field Management - Practicalities Give credit where its due the good farmers have been doing this for years the dirty boots farmer versus the tanned right arm! Remote sensing and yield mapping just helps to quantify and locate homogenous zones VS. Remote sensing and yield mapping needs to drive agro-sampling Leaf, stalk, soil, P&D

19 Conclusion Intra-field yield variability is real and there are methods of determining this on your own farm Careful intra-field management should allow for a step change in production costs on a cost per ton basis Lidar derived stalk height maps The future?..at least until the next innovation Remote sensing and yield mapping needs to drive agro-sampling Remote Sensing And / Or Yield Mapping? DEFINITELY BOTH

20 Conclusion The old adage of the best fertilizer is a farmers foot prints in the field is more real now than ever before only now, with technology, the footprints might have a more purposeful direction

21 Brian Rapson Peter Tweddle Thanks Anelisa Rianto Van Antwerpen Neil Miles