macronutrients distribution and cycling of pineapple ... papers/jtas vol. 23 (2) sep. 2000/05... ·...
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PertanikaJ. Trop. Agric. Sci. 23(2): 89 - 95 (2000) ISSN: 1511-3701© Universiti Putra Malaysia Press
Macronutrients Distribution and Cycling of Pineapple Plantedon Tropical Peat
O.H. AHMED, M.H.A. HUSNI, MM. HANAFI, S.R. SYED OMAR, and A.R. ANUARDepartment of Land Management, Faculty of Agriculture,
Universiti Putra Malaysia43400 UPM, Serdang, Selangor, Malaysia
Keywords: Nutrient cycling, pineapple, tropical peat, macronutrients
ABSTRAK
Kajian ini mengkuantitikan kemasukan, kehilangan, penahanan (tanah) dan pengambilan serta pengembalianPf K, Ca, dan Mg untuk pengurusan sisa nenas yang dibakar dan tidak dibakar. Rawatan yang digunakanadalah: sisa daun dikeluarkan dan tiada pembajaan (LRRNF), sisa daun dibakar dengan tiada pembajaan(LRBNF), sisa daun dikeluarkan dan diikut pembajaan (LRRF) dan sisa daun dibakar dan pembajaandilakukan (LRBF). Nitrogen, P dan Kdibekalkan dalam bentuk urea (46.00% N), batuan fosfat China (CPR14.00% P) dan muriate of potash (MOP 49.80% K) pada kadar 701.04, 35.56 dan 556.56 kg N, P dan Kper hektar mengikut turutan. Simulator hujan digunakan untuk menghitung larian permukaan pada plot sisadibakar sebelum penanaman. Sampel tanah pula diambil pada kedalaman 0-5, 5-25 dan . 25 sm sebelum,semasa dan selepas peringkat-peringkat pembajaan. P, K, Ca dan Mg yang tersedia diestrak menggunakankaedah dxviasid. Kaedah subtraksi pula digunakan untuk menganggar P, K, Ca dan Mgyang dilarut lesap (kgper ha). Pada peringkat matang, sampel tumbuhan diambil pada setiap rawatan dan dibahagikan kepada akar,batangy daun, buah, jambul dan tangkai serta berat keying dan kandungan P, K, Ca dan Mg di tentukan.Kandungan P, K, Ca dan Mg pada tanah, bahagian tumbuhan dan air hujan ditentukan melalui kaedah'molybdate blue' dan spektrofotometer penyerapan atom (AAS). Penambahan P, K, Ca dan Mg daripada baja,abu dan presipitasi bagi LRBF dianggarkan pada 54.25, 816.68, 103.31 dan 23.54 kg per ha. Rawatan LRRF(pembajaan dan presipitasi) pula dianggarkan pada 35.56 P, 576.05 K, 100.17 Ca dan 4.93 Mg kg per ha.Anggaran kehilangan P, K, Ca dan Mg pada rawatan LRBF adalah pada 18.44, 300.45, 66.06 dan 8.63kg per ha manakala pada rawatan IURF, nilai-nilai adalah pada 23.19, 244.88, 45.79 dan 5.49 kg per ha.Larut lesap merupakan punca utama kehilangan P, K, Ca dan Mg bagi kedua-dua jenis pengurusan dan inidapat dirujukkan dengan frekuensi pembajaan yang kurang sesuai. Satu keseimbangan positif P, K, Ca danMg dapat direkodkan untuk LRBF, 46.00% P, 28.005 K, 20.00% Ca dan 27.00% Mg dapat dikitarsemulaselepas penanaman. Bagi rawatan LRRF pula, keseimbangan positif P, K, Ca dan Mg diperhatikan. Lebihkurang 60.00% P, 20.00% K, 13.00% Ca dan 36.47% Mg digunasemula untuk rawatan ini.
ABSTRACT
This research quantifies P, K, Ca and Mg inputs, losses, retention in soil, and uptake and returns for burnt andunburnt pineapple residue in management practices. Treatments used were: leaves residue removed and nofertilization (LRRNF), leaves residue burnt and no fertilization (LRBNF), leaves residue removed and fertilization(LRRF), and leaves residue burnt and fertilization (the usual practice) (LRBF). Nitrogen, P and K were appliedin the farms of urea (46.00% N), China phosphate rock (CPR 14.00% P) and muriate of potash (MOP49.80% K) at the rates of 701.04, 35.56, and 556.56 kg N, K, and Pper ha respectively. Rainfall simulatorwas used for surface runoff measurement on burnt plots before planting. Soil sampling at the depths of 0-5, 5-25 and . 25 cm were done before planting, during and after fertilization stages. Extractable P, K, Ca and Mgwere extracted using the double-acid method. The subtraction method was used to estimate P, K, Ca and Mgleached (kg per ha). At maturity, plants were sampled from each treatment and partitioned into roots, stem, leaves,fruit, crown and peduncle, and the dry weights, ofP, K, Ca and Mg contents determined. Molybdate blue methodand atomic absorption spectrophotometer were used in determining P, K, Ca and Mg in soil, plant parts and
O.H. AHMED, M.H.A. HUSNI, M.M. HANAFI, S.R. SYED OMAR and A.R. ANUAR
rainwater, K, Ca and Mg additions from fertilizer, ash and precipitation for LRBF were estimated at 54.25,816.68, 103.31 and 23.54 kg per ha, and those of LRRF (fertilizer and precipitation) were 35,56, 516.05,100.17, and 4.93 kg P, K, Ca, and Mg per ha, respectively. The estimated amounts of P, K, Ca and Mg lostunder LRBF were 18.44, 300.45, 66.06 and 8.63 kg per ha and in the case of LRRF, the losses were 23,19,244.88, 45.79 and 5.49 kg per ha. Leaching was the major source of P, K> Ca and Mg loss for both practicesand this was attributed to inappropriate fertilization frequency. A positive balance of P, K, Ca and Mg wasrecorded for LRBF, 46.00% P, 28.00% K, 20.00% Ca and 27,00% Mg which could be recycled after cropping.In the case of LRRF, a positive balance ofP, K and Ca was observed. About 60.00% P, 20.00% K, 13.00%Ca and 36.47% Mg get recycled for LRRF.
INTRODUCTIONCultivation of pineapple (Ananas comosus) onpeat in Malaysia has been in existence for abouta century (Selamat and Ramlah 1993). The cul-tivation currently practiced on large-scale ini-tially started on small-scale basis with no fertiliza-tion. After the extensive and comprehensivesurvey of the pineapple cultivation (Dunsmore1957), the need to apply balanced fertilizers forthe growth and production of pineapple sur-faced. Consequently, various fertilizer recom-mendations (Tay 1972; Tay 1973) for varietieslike Singapore Spanish, Masmerah and Johorelwere put forward. The recommendations werenutrient response oriented and as such none ofthe studies attempted or gave due cognizance ofnutrient losses through leaching and runoff,nutrient retention after cropping not to men-tion inputs from ash and precipitation.
Perhaps when it became obvious that theprevious recommendations have oudived theirusefulness, a study was initiated to determinethe right requirement of N, P, and K of thesevarieties on peat (Selamat and Ramlah 1993).Again, physical and physiological parameters werethe focus of the study. Even though the studywas conducted at a time when nutrients additionthrough burning crop residue, precipitation,leaching, and surface runoff losses and themechanism of nutrient retention in organic soilshad advanced, a holistic approach like nutrientbalance was not considered.
With the ever increasing cost of fertilizers,plus the ever increasing awareness of the pollut-ing effects that excess fertilizer applications haveon the environment, there is a need to quantifythe movement of nutrients into, within andwithout pineapple cultivation system. A broadbased approach of this kind referred to as nutri-ent budget can be used as a tool in estimatingthe nutrient requirements of pineapple andhence help in the reduction of polluting effectsthat excess fertilizer applications may have on
the environment. The study was conducted toquantify P, K, Ca and Mg inputs, losses, reten-tion (soil), and returns for burnt and unburntpineapple residue management practice.
MATERIALS AND METHODS
The experiment was carried out at SimpangRengam Pineapple Estate, Johor, Malaysia. Thisplace is a representative area for pineapple cul-tivation on peat in Malaysia. Treatments usedwere: (i) leaves residue removed and no fertili-zation (LRRNF), (ii) leaves residue burnt andno fertilization (LRBNF), (iii) leaves residueremoved and fertilization (LRRF) and, (iv) leavesresidue burnt and fertilization (the usual prac-tice) (LRBF). The experimental unit was indi-vidual plants planted in 4 m x 12 m plot. Alto-gether 300 pineapple plants were planted ineach plot having a randomized complete blockdesign (RCBD) with 4 replications. The 1997haze incident in South-East Asia has drawn pub-lic attention and concern to the polluting effectof open burning of crop residue on the environ-ment, hence the inclusion of treatments i andiii.
Nitrogen, P and Kwere applied in the formsof urea (46.00% N) China phosphate rock (CPR-14.00% P) and muriate of potash (MOP-49.80%K) at the rates of 701.04, 35.56, and 556.56 kg ofN, K, and P per ha, respectively. These rates arethe rates used by the pineapple estate.
Prior to the start of the experiment, infiltra-tion rate was measured in all the burnt plotsusing the double ring infiltrometer. Before firstfertilization, water samples from surface runoffon the burnt plots using rainfall simulator(Kamphorst 1987) were collected, filtered andanalyzed for P, K, Ca and Mg. Throughout thestudy, P was analyzed using molybdate bluemethod (Murphy and Riley 1962) and K, Ca,and Mg were analyzed using the atomic absorp-tion spectrophotometer.
90 PERTANIKA J. TROP. AGRIC. SCI. VOL. 2S NO. 2, 2000
MACRONUTRIENTS DISTRIBUTION AND CYCLING OF PINEAPPLE PLANTED ON TROPICAL PEAT
K, Ca, and Mg concentrations were multi-plied by volume of runoff collected within 3minutes per 0.0625 m2 (area covered by the baseof the rainfall simulator). Simple proportion wasthen used to convert the values to kg per habasis. Kilogram per ha P, K, Ca and Mg multi-plied by the number of runoff days gave thetotal amounts of P, K, Ca and Mg (kg per ha)lost through surface runoff between the periodat which the experiment was started and the firstfertilizer application. Surface runoff days referto the rainy days on which runoff occurred andthese days were selected based on the assump-tion that surface runoff occurs when rainfallintensity is higher than infiltration rate (Jackson1989).
Peat core samplers of diameter 7.50 cmwere used to collect peat samples at the depthsof 0-5, 5-25 and .25 cm for bulk density deter-mination. These sampling depths were also usedto monitor leaching loss. Soil samples were takenbefore planting, fertilization and after fertiliza-tion stages. At the fertilization phase, sampleswere taken 3 weeks after fertilization so as toensure uniform distribution and dissolution ofthe fertilizers. Subsequent post fertilization sam-ples were taken bimonthly until the end of theexperiment. Rainwater was collected from threerain gauges located at three different places inthe estate at every sampling period stated andanalyzed for P, K, Ca, and Mg.
Some plants of the different treatments wererandomly selected and tagged when visual dif-ferences between the treatments began showingat the third month. Nutrients accumulation inleaves with time was monitored right from thethird month of planting until plants were har-vested by taking D-leaf and the contents of P, K,Ca, and Mg determined. D-leaf is the longestand easily identifiable leaf that provides a reli-able and sensitive indication of pineapple nutri-tional status (Py et aL 1987). At maturity, plantsfrom each treatment were randomly sampledand partitioned into roots, stem, leaves, pedun-cle, fruit and crown. These parts were ovendried at 60°C and their dry weights taken. Dryashing (single dry ashing) was adopted for theextraction of P, K, Ca, and Mg., K, Ca, and Mgdistribution were determined by multiplying theweight of plant parts by their respective concen-trations. The products of P, K, Ca and Mgdistribution per plant and plant density gave thetotal P, K, Ca, and Mg kg per ha in the distinctparts of the pineapple.
K, Ca, and Mg in soil were extracted usingthe double acid method (0.05M HC1: 0.025MH2S04) with soil to solution ratio of 1:10 (modi-fied from Van Lierop et aL 1980). The reasonbehind the modification of the extractionmethod were: (i) A dilute soil extractant helpsin eliminating the possibility of the neutraliza-tion of the extracting solution through reactionwith the soil and possibly reaction of Ca and Mgcoming from the burnt crop residue plus arti-facts in the soil, and (ii) Prolonged extractiontime plus wider extraction ratio helps in mini-mizing the effects of rewetting time variability ofdry peat (Van Lierop et aL 1980).
Weight of soil per ha at .25 cm (i.e. ap-proximately 25-50 cm) multiplied by the respec-tive concentrations of P, K, Ca and Mg gave thetotal amounts of kg P, K, Ca, and Mg per ha atthat depth (leaching zone). Weight of soil perha was estimated by multiplying a hectare vol-ume of soil at .25 cm with the correspondingbulk density. The amounts of P, K, Ca, and Mgleached per ha at each sampling period werecalculated using the subtraction method shown:TNL = NAF - NAU; where TNL = Total nutrientleached, NAF = Nutrient accumulated at .25cm in fertilized plots, and NAU = Nutrient accu-mulated at .25cm in unfertilized plots (modi-fied after Pomares-Gracia and Pratt 1978). Forthe burnt practice, leaching loss at samplingperiods started from the first sampling afterburning until the end of the cropping periodand that of the unburnt started from the firstsampling after first fertilization till the end ofthe cropping period. The depth of .25 cm waschosen as leaching zone because it was assumedthat nutrients at this zone are beyond the reachof pineapple roots as roots grow laterally (Py etaL 1987).
RESULTS AND DISCUSSIONGeneral Information
The bulk density at the depths of 0-5, 5-25, and.25 cm were 0.16, 0.23 and 0.13 g per cm3
respectively. The infiltration rate of 0.2 cm perminute was obtained. The initial status of theextractable P, K, Ca, and Mg were relatively high(Table 1). Since the land has been under culti-vation for the past 30 years, there is the ten-dency that residual accumulation might havetaken place. Insignificant difference in P, K, Ca,and Mg contents in the soil were observed forthe plots assigned the intended treatments:
PERTANIKA J. TROP. AGRIC. SCI. VOL. 23 NO. 2, 2000 91
O.H. AHMED, M.H.A. HUSNI, M.M. HANAFI, S.R. SYED OMAR and A.R. ANUAR
LRRNF, LRBNF, LRRF and, LRBF before thestart of the experiment (Table 1).
The general accumulation of the extract-able P, K, Ca, and Mg for LRRF and LRBF at 0-5 cm (Table 2) may be due to inappropriatefertilizer application frequency. Besides the lessmobile nature of P, the high accumulation of Camight have also contributed to the P accumula-tion at 0-5cm (Cogger and Duxbury 1984).
Nutrients Addition
The sources of P, K, Ca, and Mg additions werefertilizer, ash, and precipitation with fertilizercontributing the highest amounts of P, K, andCa for LRBF and LRRF (Table 3). For LRBF,ash contributed the highest amount of Mg withits P and K contribution second to fertilizer. TheCa from ash was relatively low as compared tothose of fertilizer and precipitation (Table 3).Precipitation contributed no P, however, its con-tribution of K, Ca, and Mg was relatively high(Table 3) compared to the findings ofMohammad (1981) and Veneklass (1990). Possi-bly, the distance of the experimental site fromthe sea (about 20 km), the haze problem (dur-ing the experiment) in South-East Asia and thepossibility of some ash suspension during andafter burning may account for the difference.The total amounts of P, K, Ca, and Mg fromfertilizer, ash, and precipitation addition to the
pineapple nutrient cycle were 54.25, 816.48,103.31 and 23.54 kg per ha for LRBF and 35.56,576.05 100.17 and 4.93 kg per ha for LRRF(Table 3).
Nutrient Losses
Leaching was the major source of P, K, Ca, andMg loss under LRBF and LRRF. In the case ofLRBF, second to leaching loss was through fruitharvest (Table 3). Apart from Mg where the lossthrough fruit harvest was third to leaching, P, K,and Ca loss through residue removal was secondto leaching followed by fruit harvest. Phospho-rus, Ca, and Mg loss through surface runoff wasrelatively low. The total amounts of P, K, Ca, andMg lost under LRBF were 18.44, 300.45, 66.06and 8.63 kg per ha and those of LRRF were23.19, 244.88, 45.79 and 5.49 kg per ha (Table3).
Except for Mg where leaching occurred af-ter fertilization, leaching loss of P, K, and Caoccurred before, during and after fertilization.Generally, the bulk of K, Ca, and Mg got leachedat the post fertilization stage. The reason beingthat, more of P, K, Ca, and Mg got accumulatedat the fertilization phase especially during thelast fertilization (263rd day after planting) - aperiod where the plants were nine months old.At that stage, nutrient requirement of pineappleis generally lower than during or early growth
TABLE 1The initial status of extractable P, K, Ca and Mg at three different
depths before experimentation
Treatments
LRRNF
LRBNF
LRRF
LRBF
Depth (cm)
0-55-25. 25
0-55-25. 25
0-55-25. 25
0-55-25. 25
P
482020
402020
532025
432020
K
mg/kg
540446383
503400382
472460423
535520427
Ca
1397835940
1418920865
1347800850
1370775928
Mg
906085
886058
835863
1077073
Note: Insignificant difference between treatments at same depths usingLSD <; 0.05 was observed.
92 PERTANIKA ). TROR AGRIC. SCI. VOL. 23 NO. 2, 2000
9gH2M
31H
;RIC
.SC
I
a0
i
Samplingdays
48
144
263
365
417
466
LRNF
88
40
53
33
18
23
I
P
LRBNF
115
48
45
33
13
25
LRRF
113
110
2700
1450
1145
793
TABLE 2Extractable P, K, Ca and ]
LRBF
200.00
193
2733
1207
590
500
LRNF
555
520
320
135
260
245
K
LRBNF
1395
448
373
182
228
266
Mg at various sampling
Extractable nutrients
LRRF
563
885
3300
574
265
290
LRBF
kg]
1758
1040
3093
443
368
270
LRBF
ha-I
2718
1628
1945
1222
1105
1127
stages
Ca
LRBNF
4163
1865
2265
2205
1925
1900
•:
LRRF
2198
2130
7175
4810
4838
1970
LRBF
4446
2143
7843
4873
4528
3536
j
"2,\ •••' '
LRBF
195
130
253
78
78
77
1
LRBNF
383
198
283
235
175
93
Vig
LRRF
183
180
635
233
120
95
- 3
LRBF
348
220 r
655 '
181 £
123
95
2CD
0
r>
D C
YC
I
uOO
%
*TTED O
N T
RO
PIG
*LL PE
AT
CO00
O.H. AHMED, M.H.A. HUSNI, M.M. HANAFI, S.R. SYED OMAR and A.R. ANUAR
TABLE 3P, K, Ca and Mg inputs, losses, returns and retention (soil) for burnt and unburnt practices
InputsFertilizerAshPrecipitation
Total (a)
Losses (b)FruitLeaves residueLeachingRunoff (ash)
Total (b)
Input-Loss (c)
Uptake (d)
AmountRetained insoil = c - d
P
35.5618.690.00
54.25
5.720.00
11.571.15
18.44
35.81
16.10
19.71
LRBF (leaves burnt)K
557.09240.43
18.96
816.48
71.610.00
183.6945.15
300.45
516.03
142.94
373.09
Ca
62.483.14
37.69
103.31
2.260.00
59.154.65
66.06
37.25
7.39
29.86
MgLRRF (leaves
P
kg/ha
0.4118.60
4.53
23.54
2.030.005.201.40
8.63
14.91
3.96
10.95
35.560.000.00
35.56
4.976.52
11.700.00
23.19
12.37
7.43
4.94
K
557.090.00
18.96
576.05
50.3251.16
143.400.00
244.88
331.17
65.00
266.17
removed)Ca
62.480.00
37.69
100.17
2.612.66
40.520.00
45.79
54.38
6.14
48.24
Mg
0.410.004.53
4.93
1.621.272.600.00
5.49
-0.56
2.83
-3.39
stage (Py et al. 1987) therefore, with annualrainfall of about 1917 mm coupled with the verylow clay (Stevenson 1994), the potential for P,K, Ca, and Mg lost through leaching was high.
Nutrients Removal and ReturnsUnder LRBF, the total amounts of P, K, Ca, andMg taken up (roots, stem, leaves, peduncle andcrown) from fertilizer, ash and precipitationthat can be recycled were 16.10, 142.94, 7.39,and 3.96 kg per ha. Those of LRRF (roots andstem) were 7.43, 65.00, 6.14, and 2.83 (Table 3).It must be noted that, since leaves, peduncleand crown for LRRF are not recycled, theirnutrients removal was considered loss and wereexcluded in this section.
Nutrients Retention after Cropping
After taking into account nutrients returns andlosses, the amounts (kg per ha) of P, K, Ca, andMg from inputs (fertilizer, ash, and precipita-tion retained) in the soil (at 0-5 and 5-25cm)after cropping were 19.71, 373.09, 29.86 and10.95 for LRBF and 4.94, 266.17, 48.24 and 2.27kg per ha for LRRF (Table 3).
Unutilized P, K, Ca, and Mg under LRBFwere relatively high. K and Ca retained underLRRF were also high but with low P. This low Pmay partly be due to residue removal as itcontributed about 28% (second to leaching loss)of the total P lost. It is therefore anticipated thatif this practice goes on for some time, more Pwill be depleted and hence rescheduling of fer-tilizer program will be inevitable. The negativebalance of Mg (Table 3) recorded for LRRF maybe attributed to the unaccountability of Mg ad-dition through stem and roots decompositionduring the cropping period as these parts underLRRF are normally not removed from the field.However, for the sake of accountability if it isconsidered or assumed that the amount of Mgtaken from the inputs (fertilizer and rainfall) bythese parts is proportional to the amount re-turned through decomposition, about 2.83 kgMg per ha is recycled and hence the 2.83 kg Mgper ha balances the deficit.
CONCLUSIONSThe existing fertilization regime particularly forK in pineapple cultivation on peat for the burntand unburnt pineapple residue management
94 PERTANIKAJ. TROP. AGRIC. SCI. VOL. 23 NO. 2, 2000
MACRONUTRIENTS DISTRIBUTION AND CYCLING OF PINEAPPLE PLANTED ON TROPICAL PEAT
practices is inappropriate. There is therefore theneed to reschedule the present fertilizer regime.Perhaps the last fertilization needs to be stopped.
ACKNOWLEDGEMENTSWe are thankful to Mr. Lee Sing Kim, Mr. KohSoo Koon, and Mr Faisol Abdul Ghani ofSimpang Rengam Pineapple Estate, PeninsulaPineapple Plantation, Johor, Malaysia for thepartnership in the collaborative research. Wealso acknowledge the financial support of theNational Council for Scientific Research andDevelopment, Malaysia and the encouragementof Universiti Putra Malaysia (UPM) in researchand development. We also appreciate the assist-ance of the staff of the Soil Fertility Laboratory.
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Received: 22 March 2000Accepted: 8 July 2000
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