Site Specific nutrient Management for Precision Agriculture - Anjali Patel (IGKV Raipur, C.G)

1. Course Teacher :
Dr. V. N. Mishra
(Principle Scientist)
Deptt. of Soil Science &
Agril. Chemistry
Speaker:
Anjali Patel
Ph.D. Scholar
Previous (1st sem)

2. Content
• Site specific nutrient management
• Aims
• Features
• Plant analysis based SSNM
• Soil-cum-Plant Analysis Based SSNM
• Precision agriculture
• Problems In Adoption of SSNM
• Probable strategies
• Conclusion

3. What is Site Specific
Nutrient Management ???

4. Site specific nutrient management
‘Feeding of crop with nutrients as and when
needed’
“Site-specific nutrient management (SSNM) is
the dynamic, field-specific management of
nutrients in a particular cropping season to
optimize the supply and demand of
nutrients according to their differences in
cycling through soil-plant systems.”
(Dobermann and White, 1999)

5. Site Specific Nutrient Management
• SSNM is a relatively new approach of nutrient
recommendations, is mainly based on the indigenous
nutrient supply from the soil and nutrient demand of
the crop for achieving targeted yield.
• The SSNM helps in improving NUE as it provides an
approach for feeding crops like rice, maize, wheat etc.
with nutrients as and when needed.
• For efficient and effective SSNM, use of soil and plant
nutrient status sensing devices, remote sensing, GIS,
decision support systems, simulation models and
machines for variable application of nutrients play an
important role.

6. SSNM AIMS
• Provide a locally-adapted
nutrient best management
practice tailored to the field- and
season-specific needs for a crop
• Increase in yield
• High efficiency of fertilizer use
• Improve profitability
• Improve marketable crop quality
• Improve environmental
stewardship
SOIL
HEALTH
INDICATORS
CHEMICAL
ENVIRONMENT
ORGANIC
MATTER
BIOLOGICAL
ENVIRONMENT
PHYSICAL
ENVIRONMENT

8. Important Features of SSNM
• Optimal use of existing indigenous nutrient sources such as crop
residues.
• Application of N,P and K fertilizers is adjusted to the location and
season-specific needs of the crop.
• Use of the leaf colour chart ensures that nitrogen is applied at the
right time and in the amount needed by the crop which prevents
wastage of fertilizer.
• Use of nitrogen omission plots to determine the P & K fertilizers
required to meet the crop needs. This ensures that P and K are
applied in the ratio required by the rice crop.
• Local randomization for application of Zn, S and micronutrients are
followed.
• Selection of economic combination of available fertilizer sources.
• Integration with other integrated crop management (ICM) practices
such as the use of quality seeds, optimum plant density, integrated
pest management and good water management.

9. Plant Analysis Based SSNM
• It is considered that the nutrient status of the
crop is the best indicator of soil nutrient
supplies as well as nutrient demand of the
crops.
• Thus the approach is built around plant
analysis.
• Five key steps for developing field-specific
fertilizer NPK recommendations have been
developed.

10. Contd….
1. Selection of the Yield Goal:-
• A yield goal exceeding 70-80 % of the variety-
specific potential yield (Ymax) has to be chosen.
• Ymax is defined as the maximum possible grain
yield limited only by climatic conditions of the
site, where there are no other factors limiting
crop growth.
• The logic behind selection of the yield goal to the
extent of 70-80% of the Ymax is that internal
NUEs decrease at very high yield levels near
Ymax.

11. Contd….
2. Assessment of Crop Nutrient Requirement:-
• The nutrient uptake requirements of a crop
depend both on yield goal and Ymax.
• In SSNM, nutrient requirements are estimated
with the help of quantitative evaluation of
fertility of tropical soils (QUEFTS) model.
• Nutrient requirements for a particular yield
goal of a crop variety may be smaller in a high
yielding season than in low yielding one.

12. Contd….
3. Estimation of Indigenous
Nutrient Supplies:-
• Indigenous nutrient supply
(INS) is defined as the total
amount of a particular
nutrient that is available to
the crop from the soil
during the cropping cycle,
when other nutrients are
no-limiting.
• The INS is derived from
soil, incorporated crop
residues, irrigation water
and BNF.

13. Contd….
4. Computation of Fertilizer Nutrient Rates:-
• Field-specific fertilizer N, P & K
recommendations are calculated on the basis
of above steps (1-3) and the expected fertilizer
recovery efficiency (RE- kg of fertilizer nutrient
taken up by the crop per kg of the applied
nutrient).
• Studies indicated RE values of 40-60 % for N,
20-30 % for P, 40-50 % for K in rice under
normal growing conditions.

14. Contd…
5. Dynamic Adjustment of N Rates:-
• Whereas, fertilizer P and K are applied basally (at the time
of sowing), the N rates and application schedules can be
further adjusted as per the crop demand by using
chlorophyll meter (SPAD), Green seeker and Leaf Colour
Chart (LCC).
• Recent on farm studies in India have revealed a significant
SPAD/LCC based N management schedules in rice and
wheat in terms of yield gain, N use efficiency and economic
returns over the conventionally recommended N
application involving 2-3 splits during crop growth.
• SPAD based N application resulted in a saving of 55 kg N/ha
as compared to Soil Test Crop Response (STCR) based N
application.

15. Soil-cum-Plant Analysis Based SSNM
• In this case, nutrient availability in the soil, plant
nutrient demands for a higher target yield (not less
than 80% of Ymax), and RE of applied nutrients are
considered for developing fertilizer use schedule to
achieve maximum economic yield of a crop variety.
• In order to ascertain desired crop growth, not limited
by apparent or hidden hunger of nutrients, soil is
analyzed for all macro and micronutrients well before
sowing/planting.
• Total nutrient requirement for the targeted yield and
RE are estimated with the help of documented
information available for similar crop growing
environments.

16. SSNM is a component of site-
specific crop management or
precision farming.

17. PRECISION AGRICULTURE
“Precision agriculture can be defined as the
application of principles and technologies to
manage spatial and temporal variability
associated with all aspects of agricultural
production for the purpose of improving crop
performance and environmental quality.”
(Pierce and Nowak, 1999)

18. Precision Agriculture- Concept
• Concept is simple…
1) Right Product
2) At right time
3) In right Place
4) At right Rate
• Assessing variability
• Managing variability

19. Nutrient Management in Precision
Agriculture
Source: Keith Jones, 2008

20. Why is Precision Nutrient Management
Important?
• Nutrient variability within a field can be very high
(graphs to follow), affecting optimum fertilizer
rates.
• Yield potential and grain protein can also vary
greatly even within one field, affecting fertilizer
requirements.
• Increasing fertilizer use efficiency will become
more important with increasing fertilizer costs
and environmental concerns.

21. COMPONENTS OF PA

22. Site-Specific Equipment and Technology
• Equipment
• Special equipment is not required for site-specific
management.
• Identifying areas requiring specific management can be
done with conventional soil testing and scouting techniques.
• Different fertilizer rates can be applied to different areas by
staking or flagging them, and then spreading the different
areas separately.
• Estimates of within-field distances to identify these areas
can be documented by measuring, counting rows, pacing or
other relative means.

23. Contd….
Technology Tools
GPS, GIS-based records and data analysis,
sensors and variable-rate controllers are
revolutionizing nutrient management to best meet
crop needs and efficiently utilize available
resources. Site-specific sampling, variable-rate
fertilizer application and yield monitors are
among the most common tools guiding today’s
modern nutrient management systems.

24. Technology tools
Global Positioning System (GPS)
Geographic Information System (GIS)
Remote Sensing (RS)
Variable Rate Technology (VRT)
 Farmer
Laser Land Leveler
 Leaf Color Chart (LCC)
Green seeker
 Chlorophyll Meter or soil plant analysis
development meter

25. Global Positioning
System (GPS)
• GPS is a satellite based signal
broadcast system that allow GPS
recievers to determine their position.
• GPS provides the accurate positional
information, which is useful in
locating the spatial variability with
accuracy.
• This is the satellite-based
information, received by a mobile
field instrument sensitive to the
transmitting frequency.
• GPS help in identifying any location in
the field to assess the spatial
variability and site specific
application of inputs.

26. Geographical Information System (GIS)
• GIS is a computer based system or
a type of computerized map,
provides information on field
topography, soil types, surface
drainage, subsurface drainage,
soil testing, irrigation, chemical
application rates and crop yield.
• GIS is the key to extracting value
from information on variability.
• It is the brain of precision farming
system and it has the spatial
analysis capabilities of GIS that
enable precision farming.

27. Remote sensing
• Remote sensing is a tool which
gather information in the form of
map with the help of satellites.
• RS is used for collection, processing
and analysing data to extract
information from earth surface
without coming in to physical contact
with it.
• The specific application of remote
sensing techniques can be used for-
 Detection
 Identification
 Measurement
 Monitoring of agriculture phenomena.

29. Variable Rate Applicator
• It is the implementation of gathered
information for site specific agriculture.
• It consists of farm field equipment with
the ability to precisely control the rate of
application of crop inputs and tillage
operations.
• Uses of VRT
 Nutrients/ fertilizers
 Micronutrients
 Pesticides
 Seeding
 Irrigation
• Computer controlled nozzels vary the
types and amounts of inputs according to
the variable rate application plan.

30. Yield Monitoring (YM)
• Yield monitors are attached
to conveyors or combines to
measure grain yield and
moisture content.
• Coupled with a GPS logging
location, data can be
mapped.
• Identifies in-field variations in
yield.
• Allows fine tuning of next
year’s seeding and fertilizer
applications.

31. Farmer
Farming cannot be imagined without farmer
For assessing and managing the variability,
decision-making is the key factor, and it is
to be done in consultation with the farmer.

32. LASER LAND LEVELING

35. Leaf Color Chart (LCC)
• The leaf color chart
(LCC) is an easy-to-
use and inexpensive
diagnostic tool for
monitoring the
relative greenness
of a rice leaf as an
indicator of the
plant N status.

36. Using the LCC in rice crop for N
management

37. Green seeker sensor
• A green seeker handheld
crop sensor can detect
wavelengths of reflected
light from the crop canopy
and produce a normalized
difference vegetation index
value called NDVI that is
correlated with leaf
chlorophyll.
• Based on this information,
side dress nitrogen rates that
are aligned with site specific
crop needs can be
prescribed.

39. Chlorophyll meter
• The soil plant analysis
development (SPAD)
chlorophyll meter is one of
the most commonly used
diagnostic tools to measure
crop nitrogen status.
• Released in 1984 (Minolta
Co. ltd., Japan).
• When SPAD value fell to
between 29 and 32,
indicating that additional
fertilizer is necessary.

40. Software for SSNM
• Computer or mobile phone-based tools are
increasingly used to facilitate improved
nutrient management practices in farmers’
fields, especially in geographies where blanket
fertilizer recommendations prevail.
• Nutrient Expert® and Crop Manager are
examples of decision-support systems
developed for SSNM in cereal production
systems.

41. Nutrient Expert®
• Nutrient Expert® is an
interactive, computer-
based decision-
support tool that
enables smallholder
farmers to rapidly
implement SSNM in
their individual fields
with or without soil
test data.

42. Crop Manager
• Crop Manager is a
computer and mobile
phone based application
that provides small-scale
rice, rice-wheat, and
maize farmers with site-
and season-specific
recommendations for
fertilizer application.
• The software is freely
downloadable at
http://cropmanager.irri.o
rg/home.
•

43. Whole Field vs. Site Specific Management

45. PROBLEMS IN ADOPTION OF
SSNM
• Fragmented land holding
• Lack of continuously monitoring the health and
availability of the natural resources.
• Climatic aberrations.
• Operational constraints.
• Uncertainty in getting the various inputs.
• Absence of a long standing and uniform agricultural
policy.
• Lack of success stories.
• Lack of local technical expertise.
• Land ownership, Infrastructure and Institutional
constraints.

46. Probable Strategies
• Farmer’s co-operatives.
• Pilot projects.
• Agricultural input suppliers, Extension advisors
and consultant play important role in the spread
of the technology.
• Combined effort of Researchers and Government.
• Public agencies should consider supplying free
data such as remotely sensed imagery to the
universities and research institutes involved in
Precision farming research.

47. Conclusion
• Site-specific nutrient management is gaining
popularity with the passage of time obviously
due to its in-built advantages over other
contemporary approaches.
• With an increase in understanding of SSNM,
decision support tools on fertilizer, best
management practices will be developed for
different crops and farming situation.

48. Future Indian farmer