LOSSES OF NITRA TE FROM A SANDY LOAM SOIL UNDER CORN:
L YSIMETER EXPERIMENT.
F.
Cab e a, A. Reyes, E. Femández-Boy, 1.A. Cayuela. 1.M. Mu illo and
F.
Mo eno.
Ins i u o de Recu sos Na u ales y Ag obiología de Se illa. (CSIC). Apa ado 1052.
41080 Se illa.
Addi ional index wo ds: i iga ion, Kjeldahl-N, d ainage wa e , soil wa e con en .
Abs ae
Losses
o
ni a e om
an
undis u bed sandy loam soil con ained in wo monoli h
lysime e s,
Lo
and L¡,
(1
m diame e ,
1.5
m deep) unde
com
and i iga ion (628 mm)
we e s udied. The c op was e ilized wi h O
(Lo)
and 800 (L¡) kg N ha-l. Wa e
d aining was collec ed pe iodically and analysed o ni a e con en du ing he
expe imen al pe iod (20 Ma ch 91-23 Ma ch 92).
Mean alues
o
ni a e concen a ion in he d ainage wa e we e
3.1
and 41.2
mg
NO N
1-1
in
Lo
and Ll espec i ely, he la e much highe han he limi imposed
by he EC o po able wa e (11.3 mg N l-I).
Th ee pe iods we e dis inguished du ing he expe imen : i) C op season,
in
which he
o al olume
o
wa e d ained was 310 and 47
mm
espec i ely in he
Lo
and Ll, while
he ni a e 10sses we e
o
he same o de in bo h lysime e s (
21
and
17
kg
N
ha-
l,
espec i ely); ii) D y season, in which he e was no wa e d ainage; and iii) Rainy
season, in which he o al d ained wa e was
157
and 139 mm, and he ni a e los ses 5
and
91
kg N
ha-
l in
Lo
and
L¡
espec i ely.
The g ea e amoun
o
wa e d ained in
Lo
is due o he lowe c op de elopmen
(g ain yield 4.4 and 21.3
ha-
l; o al ni o gen plan up ake 69 and 400 kg N
ha-
l, in
Lo
and Ll espec i ely).
To al ni a e losses in Ll accoun o
13%
o
he ni o gen e ilize applied. Mos
o
hese losses occu in he ainy season.
A he end
o
he expe imen al pe iod a dec ease o he soil ni a e con en was
obse ed in bo h lysime e s.
In oduc ion
P oduc ion
o
hea y yields depends
on
he use
o
la ge quan i ies
o
ino ganic
e ilize s, which can imply
an
en i onmen al isk: he pollu ion
o
g oundwa e by
ni a e. Wha e e o m
o
ni o gen e ilize
is
used, he end p oduc in he soil
is
ni a e, which is ulne able o being washed ou
o
he soil by ain o i iga ion. The
mos decisi e ac o s de e mining he magni ude
o
ni a e leaching a e ni ogen
e iliza ion, c1ima ic condi ions, ype
o
soil, soil managemen and ype
o
c op
(Gus a son, 1983; Duynis eld
e
al., 1988; Addisco e al., 1991).
Measu emen
o
ni a e los ses unde ield condi ions
is
di icul . Fi e me hods o
measu ing he concen a ion and luxes
o
ni a e lea ing he soil we e ou lined by
Addisco (1990). A good app oach
is
he use o monoli h lysime e con aining
undis u bed soil (Dowdell e al., 1984; Owen, 1990, Be gs om and Johansson, 1991).
The aim o his s udy was
o
e alua e iming and quan i y o ni a e leaching in a
highly e ilized soil unde co n and i iga ion using monoli h lysime e s. These a e
p elimina y esul s
o
a wide s udy las ing ou yea s.
2 Ma e ial and me hods
Two monoli h lysime e s
(1
m diame e ,
1.5
m deep) we e cons uc ed wi hou
dis u bing he soil p o ile and eins alled
in
si u in a plo o 0.1 ha. The soil was a
sandy loam XEROCHREPT (pH(H2
0)
7.2 and 7.1; CaCOJ 5.2 and 3.1
%;
O.M. 0.88
and 0.69
%;
Kje1dahl-N 599 and 454
mg
kg-I; NO)-N 7.5 and 10.4 mg
kg-
I a
O-50
and
50-100 cm espee i ely. These a e mean alues o 45 samples). Lysime e s we e
p o ided wi h a sys em
o
collee d ainage wa e (1.2 m deep) and wi h aeeess o
neu on p obe.
The 1ysime e s we e sown wi h co n (170000
p1an
ha-
I, 5 Ap il 1991) and e ilized
wi h O
(Lo)
and 800 kg N
ha-
I (LI
).
Fe ilize was applied in h ee s eps: a deep
e iliza ion be o e sowing (22 Ma ch 1991) wi h 1000 kg
ha-
I wi h a 15-15-15
complex NPK e ilize , and wo op d essings wi h 400 kg
ha-
I (24 May 1991) and
1000 kg
ha-
I
(7
June 1991)
o
u ea (46
%)
espec i ely. Lysime e s we e pe iodically
i iga ed (EC 2.0 dS
m-I;
SAR 2.0 meql l
I-I l;
NO)-N 10.5 mg
1-1)
ecei ing a o al
amoun
o
wa e equi alen o 628 mm. Wa e d aining was collec ed pe iodically and
analysed o ni a e du ing he expe imen al pe iod (20 Ma ch 1991-23 Ma ch 1992)
( igu e
1).
Ni a e in wa e was de e mined by ionie ch oma og aphy using a mix u e
o
bo a e-glucona e pH 8.5
as
eluen . Soil wa e con en and ain all we e also moni o ed
h oughou he expe imen al pe iod ( o al ain al1 equi alen
o
293
mm
( igu e 1».
Soil samp1es we e collec ed a 0-30,30-60 and 60-90 cm a he end
o
he expe imen
by means
o
a hin auge . Soil Kje1dahl-N was de e mined by he me hod dese ibed by
Hesse (1971). Soil
NO N
was ex ac ed by 0.2% Ca(OH)z suspension (Sims and
Jackson, 1971) and he ex ac s analysed o
NO N
by he me hod
o
Scheine (1974).
Plan heigh was measu ed pe iodically. Yield, mean weig h o ea s and o al
Kje1dah1-N
in ke nel we e de e mined a ha es .
3 Resul s and Discussion
Volumes
o
wa e d ained by
Lo
a e g ea e han hose d ained by L¡, and bo h a e
e1a ed wi h he
o1umes
o
wa e supplied by i iga ion and ain all ( igu e
1).
The
o al eomu1a i e olume
o
wa e d ained by
Lo
is also g ea e han ha by
L¡
( igu e
2). Concen a ions
o
NO N
in d ainage wa e anged om
<1
o
41.9 and
<1
o 155
mg NO)-N
1-
1 espee i ely in
Lo
and L¡. Thei mean alues we e 3.1 and 41.2 mg NO
N
I-¡
( igu e 1), he la e being much highe han he 'maximum admissible
coneen a ion' imposed by he EC o po able wa e (11.3 mg NOJ-N
1-1).
Th ee seasons can be dis inguished du ing he expe imen al pe iod: i) C op season
(20 Ma ch 1991-S Augus 1991; ii) D y season (6 Augus 1991-30 Sep embe 1991);
iii) Rainy season
(1
Oc obe 1991-23 Ma ch 1992).
Du ing he 'c op season' he lysime e s ecei ed a o al o 628 and
55
mm
o
wa e by
i iga ion and ain all espec i ely. In his season· o al wa e d ained was 310 and 47
mm
espec i ely in
Lo
and L1, and o al ni a e losses we e
o
he same o de in bo h
lysime e s
(21
and
17
kg
NO N
ha-¡
espec i ely).
Analysing he hyd ic p o iles o he lysime e s du ing he maximun de elopmen o
he c op ( igu e 3),
i
can be obse ed ha on
19
July
1991
(a ew hou s a e he
beginning
o
an
i iga ion), wa e con en dec eased h oughou he soil p o ile down o
20 and 70 cm dep h espec i ely in
Lo
and L¡. A e wa ds wa e con en emained
app oxima ely cons an a
0.227±O.OO8
and 0.151±O.004 cm3
cm-
3 (mean±SD)
espec i ely in
Lo
and L¡. Fou days la e (23 July 1991), wa e con en a 0-80 cm in
Lo
and 0-60 cm in
L¡
dec eased compa ed wi h he si ua ion
o
19 July 1991, and he
shape
o
he hyd ic p o ile we e simila o bo h lysime e s down o 70 cm dep h. F om
80 cm down in
Lo
and 70 cm in L¡, wa e con en s we e nea ly cons an , 0.226±O.011
cm3
cm-
3 in
Lo
and 0.141±O.01 cm3
cm-
3 in L¡, alues simila o hose ound a he
same dep h on
19
July. The e o e, du ing his i iga ion e en wa e con en in he soil
p o ile
o
Lo
is always g ea e han in ha
o
L¡. The same si ua ion was obse ed in all
he i iga ion e en s h oughou he 'c op season'.
As o al olume
o
wa e d ained was g ea e in
Lo
han in
L¡
( igu e 2), i
is
supposed ha wa e deple ion in
L¡
is mainly caused by he highe wa e up ake
o
he
c op in his lysime e because
o
he highe plan de elopmen . In ac , able 1 shows
ha co n plan s o
L¡
we e olle han hose o
Lo,
and ha he yield, mean weigh
o
ea s and o al Kjeldahl-N in ke nel, was also g ea e in L¡. ,
In he 'd y season' he e was no wa e d ainage and conséquen ly
no
los ses o ni a e
in ei he
o
he lysime e s.
Du ing he ' ainy season', o al wa e d ained in bo h lysime e s was simila , 15Tand
139
mm
in
Lo
and
L¡
espec i ely, 66 and
58
%
o
he o al ain all in his
pe iodo
Howe e , in he same pe iod ni a e losses in he d ainage wa e we e much highe in
L¡
(91
kg
NO N
ha-¡) han in
Lo
(S
kg
N0
3-N ha-¡). Ni a e los ses in
L¡
du ing he
' ainy season' we e he
11
%
o
he N applied
as
e ilize .
To al ni a e leached in
L¡
was
108
kg
N0
3-N
ha-¡,
equi alen o
13%
o
he o al
ni o gen applied
as
e ílize . This quan i y
is
highe han ha epo ed by C oll and
Hayes (60-80 kg
NO N
ha-¡) o sp ing-sown ce eals, and would be su icien o
cons i u e a se ious h ea o he main enance o he EC- ecommended le el in
g oundwa e (Fos e e al., 1982).
A he end o he ' ainy season' i was ound ha he con en
o
Kjeldahl-N
h oughou he p o ile dec eased in
Lo
(5733 kg N ha-¡) and inc eased in
L¡
(6396 kg
N ha-¡) wi h espec
o
he a e age ini ial con en
o
he soil (61S7 kg N ha-¡), al hough
nei he
o
he di e ences was s a is ically signi ican (P<0.05) ( igu e 4). A he same
ime, ni a e con en in he soil p o ile dec eased signi ican ly
(P<Ü.OS)
wi h espec o
he a e age ini ial con en
o
he soil (104 kg
N0
3-N
ha-¡)
inbo h
Lo
(23.8 kg
NO N
ha-
I) and Ll (38.9 kg
N0
3-N ha-I) ( igu e 4).
Figu e 5 shows a balance
o
he ni o gen inpu s and ou pu s
i i
Lo
and L¡. I can be
obse ed ha a he end
o
he expe imen al pe lod i was possible o de e mine he a e
o
mos o he ni o gen
o
he sys em. In ac ,
in
Lo
he di e ence be ween he ini ial
and inal s a es (6327 and 5853 kg N
hao!
espec i ely) was no signi ican (P<0_05)
and accoun s o so ne 7%
o
he ni ogen in he ini ial s a e. In
L!
o al ni ogen in he
ini ial s a e was 7121 kg N
hao!
and
in
he inal one 6958
kg:
N
hao!,
he di e ence
being non-signi ican (P<Ü.05) and equal o so ne 2%
o
he ni ogen in he ini ial s a e.
These di e ences, hough non-signi ican , can be explained by he inhe en e o
o
he
me hods, losses by ammonia apo iza ion om u ea, by deni i ica ion, o e en by he
eleas e
o
gaseous ni ogen (mainly a nmonia) by he plan s hemsel es.
Acknowled~men
Resea ch ca ied ou in he amewo k
o
con ac No. STEP-CT90-0032-C (DSCN)
o heCE.
Re e ences
Addisco , T.M. 1990. Measu emen
o
ni a e leaching: a e iew
o
me hods. In:
Ni a e-Ag icul u e-Eau (R. Cal e ). INRA. Pa is.
Addisco , T.M., Whi mo e, A.P., and Powlson, D.S. 1991. Fa ming, e ilize s and he
ni a e p oblem. C.A.B. In e na ional. Walling o d.
Be gs om, L, and Johansson,
R.
1991. Leaching
o
ni a e om monoli h lysime e s
o
di e en ypes
o
ag icul u al
soils_
J. En i on_ Qua!. 20: 801-807.
C oll, B.T., and Hayes, C.R. 1988. Ni a e and wa e supplies in he Uni ed Kingdom.
En i on. Pollul. 50: 163-187.
Dowdell, R.J., Webs e ,
c.P.,
Hill, D., and Me ce , E.R.1984. A lysime e s udy
o
he
a e
o
ni o gen in sp ing ba ley c ops g own on a shallow soil o e lying Chalk: c op
up ake and leaching los ses.
J.
Soil. Sci. 35: 183-190.
Duynis eld, W.H.M., S ebel, O, and Bo che ,
J.
1988. A e ni a e leaching om
a able land and ni a e pollu ion
o
g ound wa e a oidable? Ecol. Bull. 39: 116-
125.
Fos e , S.S.D., C ipps, A.C., and Smi h-Ca ing on,
A.
1982. Ni a e leaching lo
g oundwa e . Phil T ans. Roy.
SOCo
18:
103-116.
Gus a son, A., 1983. Leaching
o
ni a e om a able land in o g oundwa e in Sweden.
En i on. Geol. 5: 65-71.
Hesse, P.R. 1971. A ex book
o
soil chemis y analysis. John Mu ay Pub. L d.
London.
Owens, L.B. 1990. Ni a e-ni ogen concen a ion in pe cola e om lysime e s plan ed
o a legume-g ass mix u e.
J.
En i on. Qual.
19:
131-135.
Scheine ,
D.
1974. A modi ied e sion
o
he sodium salicyla e me hod o analysis
o
was ewa e ni a es. Wa e . Res.
8:
935-840.
Sims, J.R., and Jackson, G.D. 1971. Rapid analysis
o
soil ni a e wi h ch omo opic
acid. Soil Sci.
Soco
Ame . P oc. 35: 603-606.
Table 1 - Mean alues
o
co n plan heigh and esul s
o
co n pe o mance
a
ha es .
Lysime e Plan Plan Yield Ea Ke nel
heigh heigh
18
Jun 18 Jul mean To al
weigh Kjeldahl-N
cm
cm
kgha-
1 g %
70a
136b
218 a
247 b
4415
21295
543
a
187.3 b
1.22
1.53
Values ollowed by di e en le e s in he same column di e signi ican ly (P<O.05).
30
e
20
e
~
10
111
....
--::::c=- -=-=-,1
200
l'IU'_
-l'lU
150
;
0~~~~~~~~~--~-40
L - 1
200
z·
:'30
ySlme
e
1_
wa e
1 1
111
"!
.•
NOs-N.
150
0"
.5
20
• Z
111
'"'
" l
10
100
50
El
58
1---- "-...¡~"- -_j::.JII....4I'-......,.-+_'___l
O
e
40
§30
:;3
11120
bO
.í::
10
.!::
O
e
50
8
40
.....;'30
'iii
'j320
.¡¡¡
10
'"'
0 --'L- -...L. ---,---'~--- lL--' --"""~
O 100
200
300
400
Time
(days
( om
20
Ma ch
91)
Figu e
1 -
D ained
wa e ,
ni a e
in
d ainage
wa e ,
and
i iga ion
and
ain all
da a.
El
El
400
•
111
e
;:1
'O
300
>
111
>
:;¡
200
'5
e
8 100
OI---'4""""' ----+-+--+-+---+----l
'111
120
..c::
bO
~
100
Z
1.,
80
O
Z
111
60
>
:;1
I l
'5
40
8
;:1
U
20
Ni a e
losses
•
Lysime e
o
o
Lysime e
1
OL-
__
E......-L.._-'-----'-_...L----L---.J
O 100
200
300
400
Time
(days
( om
20
Ma ch
91)
Figu e
2 -
Cumula i e
olume
o
d ained
wa e
and
cumula i e
ni a e
losses.

3
-3
wa e
con en ,
cm cm
0.0
0.1
0.2 0.3
0.4
0.5
O
-'-- -'--~- ~-- -,-- -,
•
LO
19
JUL
..
LO
23
JUL
o
L1
19
JUL
L1
23
JUL
90
Figu e
3 -
Hyd ic
p o iles
o
he
lysime e s.
.
140
D
ini ial
lS:Sl
inal
LO
120
~
inal
L1
C.L. 95%
100
i'
< i
80
.c:
C.L. 95%
~60
40
20
O
L-~~~~L-_~2~-L~~~--~
Kjel.-Nxl0
N0
3
-N
Figu e
4 -
Con en s
o
Kjeldahl-N
and
N0
3-N
in
he
soils
o
he
wo
lysime e s.
mm!
soil
N03
-N
n
soil
Kjeldahl-N
_
i .
wa e
N03
-N
~
plan
up ake
N
D
e ilize
N
s:s:J
d ainage
wa e
N03
-N
«3
.. ::::
:ID
.!S:
10000
5000
1000
Z
500
O
ini ial
inal
(Ti
i
I
L .
O
inilial
inal
s a e
s a e
•
III1111
Figu e
5 -
Ni ogen
balance.