OptiMa-N
LIFE04 ENV/IT/000454
Optimisation of nitrogen management
for groundwater quality improvement
and conservation
The
G en eral
En v iro n m en tal C o n text
Nitrates are a soluble mineral form of
the element nitrogen and represent an important growth factor for plants. They are
normally present in farm soil because they
originate from the mineralization of organic
matter and are also present in nitrogenous
fertilizers.
The protection
of water quality
cannot be
separated from
improvements
in the
management of
nitrogen
fertilizer in
agriculture
The data provided by European networks monitoring the level of nitrates in
water make it clear that more than 20% of
ground water has a nitrate concentration at
levels which are far from negligible. The
levels tend to increase in areas where both
intensive livestock farming and crop cultivation is practised. These conditions are often present in the Po valley area where water is often found, even at great depths, with
a nitrate concentration of more than
50mg/litre, the drinking water limit fixed by
the European Union.
The so-called “Nitrates Directive” was
passed at the beginning of the 1990s precisely in an attempt to tackle nitrates pollution from farming, leading to the identification of “vulnerable areas” in the various regions.
What can we do to limit the danger of
excess nitrates polluting our water resources? First of all an effort must be made
to make a substantial reduction in nitrate
losses from farming, that is, nitrates which
are present in the soil as nutrients. Without
this step of fundamental importance all oth-
OptiMa-N Layman's Report
er initiatives will be ineffective and excessively costly.
It is estimated indeed, that 50 to 80% of
nitrates introduced into European water resources come from farming, a figure which
fluctuates significantly from country to
country and basin to basin. In Italy, the contribution of agriculture to nitrate enrichment
of both soil and water is more than 60%.
2
In general each farm can be seen as a
unit of “nitrogen exchange” with the out-
THE NITRATES
The soil nitrates not absorbed by the crops are
dissolved by water and
may then transfer to:
 surface water where
they cause eutrophication with the excessive growth of algae
and the death of fish
and other organisms;
 the water table, contributing to its contamination
which
can
reach levels where the
water has to be declared unfit for drinking. Nitrates are potentially toxic for both
humans and animals.
side environment. It imports nitrogen from
the outside, particularly in the form of feed,
forage crops and fertilizer, exporting it in
the form of the sale of farm produce. The
nitrogen leaving in the form of farm produce is less than the amount imported in the
form of the means of production. This indicates the creation of a nitrogen surplus
and the greater the intensity of production,
the greater the size of the surplus. It must be
presumed that part of this surplus will be
taken up in the soil, increasing the nitrogen
reserve and hence subject to leaching. It is
dissolved in the water percolating down
through the soil and hence introduced into
lower layers. Research has been concentrating for some time now on increasing the efficiency of nutrient use, nitrogen in particular, introduced to farm crops through synthetic fertilizers and livestock effluents.
This aspect has become of particular importance in the context of current environmental regulations.
The issue of efficient use of nitrogen
was central to the demonstrative project
“Optimisation of Nitrogen management for
the improvement and conservation of water
quality” – Optima-N, financed by the
European Commission in the context of the
“Life Environment” instrument, with cofinancing from the Region of Emilia-Romagna, the provinces of Parma, Reggio
Emilia and Modena, Enia S.p.A., Ascaa
S.p.A. and Hera S.p.A.
T h e Pro ject
Optima-N is one of the 28 Italian projects financed in 2004 by the European Union through LIFE, the programme that supports environmental policies and actions in
the countries of the Union. The Project
began in October 2004 and concluded in
September 2007 and covered the provinces
of Parma, Reggio Emilia and Modena. This
area is characterised by livestock farming
connected to the production of ParmigianoReggiano cheese and Parma ham as well as
crop farming such as cereals and industrial
and horticultural crops.
It is a demonstrative project and hence
with an important component involving
communication and dissemination aimed at
both sector technicians and farmers with the
following goals:
 to test the impact of nitrogen fertilisa-
tion on the nitrate pollution of the water
table;
 to promote the conduct of farming prac-
tices with a reduced environmental impact by heightening the awareness of the
farmers.
The Project activities were organised
into a number of different inter-connected
tasks which can be summarised as follows.
1. The conduct of fertilisation trials designed to demonstrate how to optimise
nitrogen levels to the specific crops and
to calibrate the method used for the calculation of the nitrogen balance to a
range of different pedoclimatic conditions in different farms. This work was
carried out on “pilot farms” selected
within the area covered by the provinces
of Parma, Modena and Reggio Emilia.
2. The comparison of different methods for
the measurement of nitrates to establish
whether it would be possible to speed up
and simplify the data collection process.
3. the activation of an Internet service to
assist technicians in fertilizer planning
on the basis of real field data.
4. The calculation of the nitrogen balance
at different levels (whole farm, barn,
single plot) in a “demonstrative farm”
with dairy cows in order to optimise
overall use of the element.
5. An exchange of experiences with a
group of specialists from different
European countries in order to identify
common methodologies and to transfer
results to different socio-economic and
agricultural contexts.
6. Direct dissemination activities through
lectures, demonstrative days and seminars and indirect actions by means of
technical articles and the Project’s Internet site (http//:www.crpa.it/optiman).
The Project has been carried out by
CRPA S.p.A. (the co-ordinating organisation also acting as the funding recipient) in
conjunction with its project partners
“Fondazione CRPA” and the “Stuard” experimental farm in Parma.
T h e partn ers
CRPA SpA – Reggio Emilia is a research and consulting organisation dealing
with the improvement of the livestock sector and the related agro-industry by means
of research, studies, dissemination and technology transfer actions. Its main Shareholders are local authorities, some farmer unions and a bank foundation. The company
has nine research units: forage crops and
agronomy, environment, economics, livestock production (cattle and pig husbandry),
software development, machinery and farm
buildings, dissemination of research results
and communication (hosting a European
Carrefour – Carrefour Emilia). On the sci-
entific front, C.R.P.A. has been operating
with the most important research staff from
Italian agriculture faculties and universities
and other scientific organisations for 20
years. The Centre has been involved in several research projects funded by the Ministry of Agriculture, the regional government, private customers and by the EU.
Fondazione CRPA Studi e Ricerche
ONLUS (Fondazione CRPA) – Reggio
Emilia. This is a no-profit research organisation funded in 1998 by means of a spinoff from CRPA SpA. It carries out mainly
applied research and field trials concerning
forage crops, environmental impact of agriculture and agro-food plants, farm building,
machinery and implements. Fondazione
CRPA also carries out work connected with
economic issues, concerning the impact of
new technologies, production methods and
results of the research on the production
costs of food and intermediate products.
Fondazione CRPA has now completed more
than 20 research projects in partnership
with other research organisations since its
initial foundation.
Azienda Agraria Sperimentale “Stuard” (AAS Stuard) – Parma is a Research
Station. It has the status of an “Azienda
Speciale” (Special Farm) of the Province of
Parma. It is mainly concerned with the
management of research and experiments
on agriculture and environment. The Centre
is located in the Po Valley, Northern Italy,
and its research is for the most part concentrated on Integrated Crop Management and
Organic Production of the main crops of the
area: tomatoes for processing and other horticultural crops, fodder crops, cereals and
other crops. It has been responsible for the
conduct of more than 50 trials every year
since 1983.
3
THE PROJECT
General Objective:
to improve nitrogen management at the field level and the farm taken
as a whole in order to
limit the environmental
impact of farming activities.
The Means Used:
 the testing of the nitrogen balance in the
field;
 the production of software for the management of nitrogen fertilizer;
 the farm nitrogen balance to optimise the
overall management
of the element;
 dissemination activities aimed at providing
the related information
to students, technicians and farmers.
T h e G eo g raph i cal are a wh ere th e wo rk h as been co n cen tr ated
The area covered by the project comprises the provinces of Parma, Reggio
Emilia and Modena (Emilia Romagna Region, Po river basin). This area is characterised by the concurrent presence of intensive dairy farming (ParmigianoReggiano cheese), meat production (Parma ham), and field crops such autumnwinter cereals, tomatoes for processing and horticultural crops.
To carry out the activities 18 farms were selected on the basis of farm type
(specialising in crops or livestock), soil type and whether or not coming within
the vulnerable area, it also being a condition that the farmer agree to apply the
agricultural practices indicated and to hold demonstration activities for the benefit of other arable and livestock farmers.
OptiMa-N Layman's Report
cattle supported by the farm and the crop
rotation practised), the different types of
soil and different climatic conditions of heat
and rainfall.
RESULTS
4
T h e l o cal N itrate Mo n it o rin g n etwo rk
8
220
6
170
4
120
78 %
67%
2
54 %
0
70
Asportazioni
N (kg N/ha)
N uptake
(kg N/ha)
CRA-N
N ef f iciency
(%)(%)
Produzioni
Yield
(t/ha) (t/ha)
A series of experiments were carried out
in the context of the Project aimed at confirming and demonstrating the environmental improvement that could be obtained
by the rationalisation of nitrogen fertilization.
20
0-N0
60-N1
90-N2
120-N3
Apporti azotati (kg ha-1)
Grain
Granella
N
uptake
Asportazioni
N
ef -f iciency
CRA
N
The research was based on the following experimental hypothesis: if
the balance method is able to identify the Optimum Technical Dose
(B), this point also corresponds with maximum production.
The experimentation was in the form of
a field trial of the nitrogen balance method,
representing the best method of identifying
the optimum dose to be given to the crops.
It is in the form of a balance sheet with positive entries on the one side, that is, both anthropic and natural contributions and deductions in the form of crop requirements
on the other.
The method has been calibrated and
tested to meet different farming situations
(presence of livestock and the numbers of
The
experimentation
concentrated
largely on autumn-winter cereals (wheat
and barley) since the autumn and spring
represent the periods most at risk from nitrate percolation, together with maize and
tomatoes (given these crops’ requirement
for high levels of nitrates and irrigation).
The crops, fertilized with increasing doses
of nitrogen, were sampled at harvest and
analysed to obtain production and take-up
measurements. Samples were also taken
from the soil at times of fundamental importance in the crop cycle to measure nitrate levels.
These activities made it possible to
identify the final destination of the nitrogen
provided to the crops in different doses,
also making it possible to fine tune the estimating equation for the simplified balance
on the basis of agronomic data (taken from
the soil and the crops) obtained in the field.
The research was based on the following experimental hypothesis: if the balance
method is able to identify the Optimum
Technical Dose (B), this point also corresponds with maximum production.
The Graph illustrates the point.
Grain production and N uptake. Production increases up to the dose identified
by the balance (N2 = B) then decreasing
with additional amounts (N3 = B + x). The
cause of the decrease in production may be
a lodging induced by the excess of nitrogen.
Level of nitrates in the soil. The evaluation of the presence of nitrates in the soil
should show the absence of dangerous increases in residual nitrates up to the dose
Sum m ary of “4N ” tri als ”
Each trial involved the comparison of four different nitrogen doses (4N) distributed in two or three applications.
The trials all followed a standard pattern:
Nitrogen level
N0
Quantity of N applied:
0
Nitrogen level
N1
Quantity of N applied:
B–x
Nitrogen level
N2
Quantity of N applied:
B
Nitrogen level
N3
Quantity of N applied:
B+x
B = Optimum Technical Dose estimated by means of the Nitrogen balance method.
x = quantity of N varying from crop to crop, which is useful for demonstrating the effect of the increase and
reduction of nitrogen applied with respect to the optimum dose.
N2; there should be a clear increase in soil
nitrogen levels on the application of additional amounts. The hypothesis is thus that
the introduction of excess nutrients with respect to actual need will be stored provisionally in the soil and thus susceptible to
leaching with autumn and winter rains.
Fertilizer management is effected by
farm centre. Each farm centre is an entity
defined by the user without any connection
with data from official personal records.
The farm centre groups together a specific
number of plots he has chosen on the basis
of geographical location or simplicity of
management within the software.
Sim . Ba- N : a s im pl e an d
ef f ec tiv e
to ol f o r th e
dr awin g up o f n itro g en
f ert il iz atio n pl an s
The user may use the programme by reference to one or more farm centres. Each
farm centre is defined by:
SIM.BA-N: a tool for the management of nitrogen fertilizer
The calculation system for the Optimum
Technical Nitrogen Dose for crops, calibrated and assessed by means of the experimentation described and explained above,
was translated in a software called Sim.BaN – which can be used free of charge over
the Web by visiting www.crpa.it/optiman.
The software is thus based on the simplified nitrogen balance and allows the user
to identify the dose of N (kg N/hectare) advised in order to achieve a given production
target in different farm plots.
The software allows the user to manage
fertilization plans simply and quickly, also
acting as a record of past farm data, a kind
of farm notebook. The programme is also
able to provide dynamic assistance in that it
allows for quantities to be updated over the
season in relation to seasonal trends and the
applications effected previously.
How Sim.Ba-N functions
Access to the programme is by a password
provided free of charge on request. The information entered thus remains private and
is only available to the user.
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 location (local council, province and re-
gion);
 intensity of livestock;
 meteorological data. Sim.Ba-N makes it
possible to connect with the currently
available database for Emilia-Romagna.
To calculate the advised dose the programme requires at least one soil analysis
per farm centre. Obviously, the reliability of
the advice will depend on the quality of the
data provided to the programme. If the data
entered are approximate in nature the advice will also be imprecise.
The farmer will be required to define the
Crop Division on a yearly basis. This allows the association of the information necessary to calculate the fertilizer dose to be
applied to each plot.
Sim.Ba-N can be used to
identify the doses of
nitrogen to be applied to
crops. Its feature allowing
the storage of past farm
data also makes it useful as
a kind of farm notebook.
In addition the user is required to record
the fertilization already carried out within
the section fertilization by crop thus allowing the programme to deduct the fertilizer already applied from the quantities initially identified as advisable. This figure is
essential to be able to take account of the
residual effect in subsequent years.
The programme contains a generic list
of both organic and chemical fertilizers
which the user is able to customise with the
addition of the fertilizers actually used to-
Dosi di azoto: quantity of N to
be applied
Apporto di azoto: quantity of N
previously applied
The output of the Sim.Ba-N software: an example of the advised dose of nitrogen
Bilancio dell’azoto: difference
between the quantity of N to be
applied and the N distributed
OptiMa-N Layman's Report
gether with their composition in the private
tables.
One of the highest priority project goals
is to maximise the efficiency of nitrogen
fertilization. The large amount of field data
produced and the intense efforts to disseminate the related information have certainly
contributed to its successful achievement.
To this end we would hope that the use of
the programme Sim.Ba-N by technicians
and farmers proves to be a decisive contribution to the same goal. The simplicity with
which it can be used and its adaptability to
individual crop situations means that it is
capable of guaranteeing the application of
project results into the future.
6
T h e o ptim is at io n o f th e
ef f i cien cy o f us e o f n i tro g en at a f arm s cal e
The project took into consideration not only the fertilization, but also the nitrogen cycle at the farm level:
the drawing up of balances
at different levels (field,
barn or farm) improved the
overall efficiency of nitrogen use.
The analysis of the nitrogen cycle in a
particular farm is useful in assessing the
headings and transitions which have the
greatest influence on the nitrogen balance
and which processes are less efficient. Once
such information is to hand it becomes possible to identify practices and alternative
systems capable of improving the management of nitrogen contained in fertilizers,
forage crops, feed and livestock effluents.
A demonstrative research project has
been conducted at the dairy farm producing
milk for Parmigiano-Reggiano cheese run
by Luca and Silvio Cotti in Pilastro di
Langhirano in Parma as part of efforts to
provide guidance for dairy farmers in
achieving greater environmental sustainabInput to
soil
Environmental
losses
SOIL
Input to
bar n
Crop
pr oducts
CROPS
MA NURE
LIVEST OCK
Scheme of the farm gate balance
A nimal
pr oducts
ility. The research involved intervention
with the nitrogen cycle, seeking to optimise
the use of the element at different levels
(crop, cowshed, farm as a whole).
At the farm level, the efficiency of the
conversion from ingested nitrogen to saleable nitrogen (milk and meat) was variable
over the three years of the project’s work.
This showed that it was only possible to reduce the percentage of nitrogen excreted by
the animals by means of a careful management of the resources available. This must
be based on a continuous monitoring of the
characteristics of the forage crops and feed
available.
At the level of the farm as a whole, improved efficiency in nitrogen use was progressive over the three years. It was derived
mainly from an improved use of the available fertilizers including livestock effluent.
This latter permitted savings to be made in
the purchase of chemical fertilizer while at
the same time maintaining optimum production levels.
The drawing up of balances then allows
reference to numeric indices summarising
the efficiency of nitrogen use at the specific
level under consideration (field, barn or
farm). These indicators, corresponding to
the practices that the farmer may implement
on his farm, can be used to further heighten
farmers’ awareness, stimulating them to a
course of action which further reduces their
environmental impact.
Monitoring nitrate percolation
Instrumentation for checking water and
nitrate percolation in the soil and sub-soil
(tensiometers and porous ceramic cups) was
installed in a field on the same demonstrative farm, the cups being buried down to a
depth of 5 metres.
The crops grown on the field were alfalfa, tall fescue and a mixture of the two.
The pure fescue was fertilized with cattle liquid manure with doses significantly above
170 kg/hectare per year, the limit set by the
Nitrates Directive, while with the mixture
the quantities applied came close to, but did
not exceed, this limit. The pure alfalfa was
not fertilized with nitrogen being able to fix
it from the atmosphere itself.
Notwithstanding the fact that not particularly high levels of production were
achieved for forage and protein, the pure
fescue grass was able to maintain safety
levels of nitrate concentration in the soil
and soil retention water, generally less than
that measured for the non-fertilized alfalfa.
The mixture too was able, with excellent
production of forage and protein, to limit
the risk of nitrate percolation.
In the light of this and other trials it can
be confirmed that the meadow forage crops
are good candidates for the role of crops offering protection to the water table from nitrate infiltration.
Farm balance of nitrogen (kg/ha per year)
2005 2006 2007
Inputs
Feeds
Roughage
Straw
Mineral fertilisers
Manure (horses litter)
Seeds and seedlings
Atmospheric depositions
N fixation by lucerne
Totals
61,1
4,4
4,6
123,2
24,3
0,5
16,4
65,2
299,7
62,3
11,1
3,2
84,9
32,6
0,7
16,4
64,9
276,1
66,9
2,7
74,1
18,5
1,0
16,4
77,0
256,6
Outputs
Crop products
Milk
Animals
Farmyard manure
Totals
28,6
28,4
2,3
59,3
41,0
28,8
3,2
3,7
76,7
35,7
30,1
3,5
69,3
Inputs-outputs
Inputs – Outputs (Surplus)
Outputs/Inputs
240,4 199,4 187,3
0,20 0,28 0,27
The
d iss em in atio n
of
th e res ul ts an d th e ex ch an g e o f exper ien ces
with e xperts
Over the last three years a variety of
communicative and demonstrative activities
have been organised. These include the following examples: visits to the pilot farms
and the demonstrative farm (demonstration
days and guided tours), meetings with students, courses with technicians and the final
project conference.
Thanks to the involvement of regional
structures, training managers in the farming
sector and high schools specialising in agricultural studies, it has been possible to involve a large number of farmers, students
and technicians simply through direct contacts, amounting to an overall total of more
than 1200 people. These meetings and
courses have given rise to considerable
levels of interest, confirmed by the number
of participants and the animated discussion
generated by the results obtained by the
Project.
7
The publicising of the results has also
been effected through a series of technical
articles, a newsletter aimed at technicians
and the Project’s Web site.
The Web site htpp//:www.crpa.it/optiman contains information relating to the
goals, the initiatives, the participants and
the most important technical aspects of the
Project. The site has been updated periodically with the results obtained from the monitoring sites and in the demonstrative farm,
with materials designed to publicise the
project work and bibliographical references.
The European Orientation Group has
been set up with the purpose of exchanging
information and experiences during the
conduct of the Project activities, to check
the effectiveness and transferability of the
results to different situations and the organisation of the final International Conference.
The European Orientation Group is
made up of technical experts and political
representatives drawn from seven countries
within the European Union and has made it
possible to promote dialogue and the exchange of experiences, with an enriching
effect on the Project as a whole. The members of the Group took an active part in the
meetings that proved to be particularly
helpful. In fact, their suggestions, opinions
and ideas resulted all contributed towards
the improvement of both technical aspects
and the dissemination of the results.
The dissemination has been
carried out by means of
several meetings with students, technicians and
farmers.
An international conference
was held at the end of the
project. The results have
been
publicised
also
through a series of articles,
a newsletter aimed at technicians and the Project’s
Web site.
OptiMa-N Layman-s Report
Coordination
Centro Ricerche Produzioni Animali S.p.A.
Partners
Azienda Agraria
Sperimentale
“Stuard”
The European Orientation Group
Frans Aarts
Paesi Bassi
Fondazione C.R.P.A. Studi e Ricerche ONLUS
Sponsors
Plant Research International
Steve Jarvis
Regno Unito
Institute of Grassland and
Environmental Research
André Pfimlin
Francia
Institut de l’Elévage
Stefan Pietrzak
Polonia
Institute for Land Reclamation and
Grassland farming
Theodore Karyotis
Grecia
National Agricultural Research
Foundation.
Francesco Mundo
Italia
Danimarca
Ministry of Environment
Steen Gyldenkaerne
National Environmental Research
Institute
Provincia
di Parma
Provincia
di Reggio Emilia
Provincia
di Modena