PROCEEDING ISBN : 971-979-1911·15·9

International Seminar on Tropical Natural Resources 2015 "Toward Sustainable Utilization of the Tropical Natural Resources

for a Better Human Prosperities"

Reviewer: \~~o< . Pror. l m1 Phaik Ecrn Dr. Oni ) ulaart i Dr. Ran\ 1r Sangh l'roj. Dr. Jenne~ Gannon · Prof. Tauf'ik Fau:t i Prof. I Kon1ang Darnar .Ja} '-' Prof. Sur} a J lad i Dr. Dahlanuddin Bflmb,mg Tlari Ku~u1no, Ph.D . \luh ikrnat ullah, Ph.D

Editor : drh. Madr Sriasih, Ph.D Dr. I lamul Had i Dr. F<:1turrahn1an ~luhsinul lhsan, M.Sc

University of Mataram Indonesia

june 10·13, 2015

Mataram University Press

..

-~---

OPENING SPEECH- RECTOR UNIVERSITY OF MATARAM

International Seminar on the Tropical Natural Resources 2015

Respected Guests,

Keynote speakers,

Seminar participants,

and all other participants.

On Behalf of all staffs ofthe University ofMataram, I welcome you all to Lombok, a

beautiful island in West Nusa Tenggara Province, where the University of Mataram

is located. Lombok is known for its natural and cultural diversity where you can

enjoy traditional cuisines, beaches, waterfalls, mountain, traditional villages and

handicraft of many ethnics including Sasak, Samawa, Mbojo, Balinese, Chinese,

Arabic, and many others.

As the Rector of the UntYersity of Mataram, it is a great honour for me to address the

opening of ·'the International Seminar on the Tropical Natural Resources" here at the

University of Mataram, which wi ll be held from lOth to l3th June 2015, with a theme

"toward sustainable utilization of the tropical natural resources for better human

prosperity". The main aim of this seminar is to gather scientist from all over the

world to share their ideas, knowledge and experien9es and to build network for

possible future collaboration.

As we are aware that sharing knowledge and expenences from speakers are

extremely valuable in a seminar, therefore I would like to express my high

appreciation, first, to the keynote speakers from overseas (USA, Australia, New

Zealand, China, Singapore, Malaysia, the Philippines) and from Indonesia for their

willingness to come to Lombok to share their acknowledged works. Your effort and

contribution to this seminar are absolutely valuable. Second, my high appreciation

also goes to the national speakers and all other participants, including the speakers

from University ofMataram and local universities in West Nusa Tenggar Province,

ii

your participation in this seminar not only will give incredible share of ideas, skills

and knowledge that you have, but also will improve the academic environment that

we are developing in this university. I hope this seminar will be a good forum, not

only for communicating and sharing ideas, knowledge and experiences, but also for

building networking for future collaboration

I would also like to take this opportunity to express my appreciation to the sponsors

(Bank Mandiri, Bank BNI, Bank BRI, Bank BTN, Bank Bukopin), which have given

some contribution to this seminar. Last but not least, I would like to thank the

steering and organizing committee as well as all other supporters and participants,

without their effort, commitment and hard work, this seminar will not run well.

Finally, I wish you most successful seminar, enjoy Lombok Island and hope to see

you again in other forum here at the University of Mataram.

Prof. Ir. Sunarpi, Ph.D

Rector of the University ofMataram

iii

TABLE OF CONTENTS

Cover

Opening Speech -

I

Table of Contents .. . Ill

Kamaruddin A., Aep Saepul Uyun, Jombrik, Slamet Rahedi Sugeng and I

Ima Jaya diningrat

Muhamad Ali, Sulaiman N. Depamede, Bagus DH Septyono, Alis 9

Mukhlis, Sahrul Alim, Muhamad Amjn, and Mohammad Ashari

Suseno Amien, Arum Dani Atmojo, Neni Rostini, and Tia Setiawati 21

Lalu Panji Imam Agamawan, Kadarwan Soewarru, and Nurlisa A. Butet 30

Ansar, Satrijo Saloko, St. Rohani, and Nazaruddin 38

TGP. Muliarta Aryana, BB. Santoso, M. Zairin, N. Farid, NT. Ramdani 46

Luh Gde Sri Astiti , Lisa Praharani dan Rjasari Gail S. 58

Sri Puj i A tuti 67

Nunik Cokrowati, Aluh Nikmatullah, Sunarpi, Zaenal Abidin 74

Nanda Diniarti, Nunik Cokrowati, Oewi Nur'aini Setyowati 78

Ardiana Ekawanti , Nurkaliwantoro, Warindi 87

Wiwik Ekyastuti and Hanna Artuti Ekamawanti 94

Elsanti SU. Sinulingga, Arifien Yunus, fusyah 103

Ni Made Laksmi Ernawati, Febriana Tri Wulandari, and Bambang 121

Supeno

f-Iery Wijayanto, Tri Wahyu Pangestiningsih, Temia Twin Pangesti, 128

Kumianti

Muhammad Izzuddjn Faizal, Bagyo Yanuwiadi & Marsoedi 136

Varian Fahmi, Jdham Sumarto Pratarna, Asep Ridwanudin 145

Dwi Laksmiwati and Aliefinan Hakim 154

Sitti Latifah and Taslim Sjah 165

Kumiawati Lely, Handayani Sri Seno, Kusuma Dedi Purwanto Indra 180

Yuda H Fibrianto, July A Salam, Heru Susetya, Setyo Budhi, Ariana, 185

Gustari, Widagdo S Nugroho, Teguh Burupitojo I I

iv

Laura Flowrensia, Ulfah Juniarti Siregar, Noor Farikhah Haneda, Arina 191

Nur Faidah

Mursal Ghazali 199 -

Guyup Mahardhian Dwi Putra. Sumarjan 206 - -----Baiq Rien Handayani, Rid\van, Syarifuddin, Oni Yuliarti, Wiharyam 21-l

Werdiningsih and Ellok Fulkiah

Sukayat Harrnoko, Arifien Yunus, Sinurat JaJ;nes, Aisyah 227

Dini lflakhah, and Ratna Ediati 240

Wahyu Irawati, Adolf JN. Parhusip, and R. Nida Sopiah 249

Laswi Irrnayanti, Iskandar Z.Siregar, Prijanto Pamoengkas 261

Lalu Jamiludinand Lukman Atmaja 269

Baiq Dewi Krisnayanti, Sukartono, Ardiana Ekawanti, Christopher 281

Anderson,

Rina Kumianingsih, Sri Suyatni,·Faturrahman 289

D\.vi Liliek Kusindarta, Dewi Kania Musana, Hery Wijayanto, Surya 297

Agus Prihatna, AETH Wahyuni_ Widagdo Sn Nugroho. Heru Susetya,

Yuda Heru Fibrianto

IGM. Kusnarta, Sukartono, M. Ma'shum, and Mahrup 304

B. H. Kusumo, M.J. Hedley, M. Camps Arbestain, C. B. Hedley , 316

R. Calvelo Pereira , P. Bishop and A.F. Mahmud

Martha E. Siahaya , Messalina L. Salampessy, lndra G. Febryano, 342

EmaRositah, Rato F. Silamon, Andi C. Ichsan

Sri Mulyani, Ambo Tuwo, Rajuddin Syamsuddin, and Jamaluddin Jompa 352

Tri Mulyaningsih, Djoko Marsono, Sumardi and Isamu Yamada 361

Murniati, Surya Hadi, Dini Hendriwati 383

Nalle, Catoo~ie Lusje, Marlin R. K Yowi and Asri A. Widu 394

Tri Wahyu Pangestiningsih, Trini Susmiati, Hery Wijayanto 407

Sari Novida, Sri Puji Astuti 413

IGM Arya Parwata and Bambang Budi Santoso 420

BamhanQ" J Priatmadi. Akhmad R. Saidv. Meldia Se tiana p 4~7

v

Seto Priyambodo, E.Hagni Wardoyo 437

Emi Roslinda, Wiwik Ekyastuti, Siti M Kartikawati 452

Rustam 461

Rustam 469 ---- ---- --

Rahmat Sabani and Amuddin 477

Akhmad. R. Saidy, Afiah Hayati, Meldia Septiana 488

Dewi Nur'aeni Setyowati 512

Hasyyati Shabrina, Ulfah J. Siregar 520

I Made Sudarma 528

I Made Sudantha dan Suwardji 541

Febi Wahyu Sulistyadi, Bagyo Yanuwiadi and Marsoedi 552

Surya Hadi , Lalu lrfan Hadimi, Siti Raudhatul Kamali, Baiq Desy 559

Ratnasari, and Surayyal Hizmi

Liana Suryaningsih and John K. Fellman 568

Lolita E Susilowati,Zaenal Arifin and Bambang Hari Kusumo 582

Muhammad Zaenudin, Zaenal Abidin, Bagus Dwi Hari Setyono 597

Zainun , Abbas Zaini , Wiharyani Werdiningsih, Taslim Sjah dan Hadijah 605

,,

427

Changes in Rice Production in Acidic Tropical Soils as Influenced by Fly-ash Application

Bambang J. Priatmadiu, Akhmad R. Saidl, Meldia Septianau

1 Department of Soi l, Fa<.:ulty of Agriculture, Lambung Mangkurat Un1vers1ty, Banjarbaru 70714, Indonesia. Phone: +62 511 4777540, fax : +62 511 4772254.

email: asaidy@unlam.ac.id

· Abstract

Fly-ash (FA) is largely alkaline in nature and contains many essential elements for plant growth along with toxic metals. Therefore, fly-ash is potential to be applied as soil ameliorate that may improve soil properties and plant growth. In this experiment we studied the changes in chemical properties and rice production of acid sulphate soils amended with fly ash. Six different amounts ofF A, viz. 0 ( 100% soil), 5, 10, 20, 40 and 75 tones FA ha·' were added homogenously to 6 kg of soi ls in pots of PVC and then chemical properties of acid sulphate soils were observed after a 3-week of incubation. After the observation of soi l properties, rice was planted onto the pots. Results of study showed that fly-ash application improved soi l pH and exchangeable Ca. However, the availability of nitrogen of acid sulphate soils decreased significantly with fly-ash application. The experiment a lso showed that fl y-ash application to soil s improved rice growth (height plant, number of tille rs. dried-weight root and dried-\\'eight shoot) and rice production. Application 20 tones FA ha-1 resulted in higher rice production than the application 0, 5 and 10 tones FA ha-1, and jncreasing subsequent the amount of FA application did not significantly increase the rice production. Results of this study demonstrate that low-level fly-ash application resulted in the improvements of soil chemical properties and rice production.

Keywords: fly-ash application; soil ameliorant; heavy metals; sub-optimal low land

1. Introduction

Main problem in rice cultivation in acid sulphate soils is low productivity.

Data from the Department of Agriculture, South Kalimantan (2007) showed that rice

production in acid sulphate soils ranged from 3.14 to 4.30 tonnes per hectare. One of

the factors limiting the growth of rice in acid sulphate soils is low soil pH. The

observations in the province of South Kalimantan showed that the pH (H20 ) of the

acid sulphate soils ranged between 3.96 and 4.88 (Saidy et al., 2005). Low soi l pH

results in low availability of soil phosphorus, calcium, magnesium, potassium and

sodrum (Bohn et al., 2001 ), and this condition eventually result in unhealthy plant

growth. Improvements soil properties can be done by adding ameliorant material into

428

the soil to increase soil pH and simultaneously improve the content of some nutrients

such as Na, Ca, K and Mg.

Fl y ash ( r-A), a coal combustion residue, is an amorphous terroalumino sil icate" ith

a matrix very similar to soil. Elemental composition ofF A (both nutrient and toxic

elements) varies due to types and sources of used coal (Comberato et al. , 1997).

Addition of FA to soil may improve the physico-chemical properties as well as

nutritional quality of the soil and the extent of change depends on soil and FA

properties. In view of the high cost of disposal and environmental management,

utilization of FA in agricultural sector could be a viable option. Its use in agriculture

was initially due to its liming potential and the presence of essential nutrients, which

promoted plant growth and also alleviated the nutrient deficiency in soils (Mittra et

al., 2005).

The disposal of fly-ash (FA) from coal-fired power stations causes significant

economic and environmental problems. Dumped FA may adversely affect the

environment by mobilization or 1ts hazardous constituents and thus contaminate the

surface and ground waters, soi ls and vegetation. Fly-ash is largely alkaline in nature , and contains many essential elements like Si , S, B, Ca, Mg, Fe, Cu, Zn, Mn and P.

Therefore, FA may be applied to soils as soi l amendment to improve soil properties

and thereby enhance plant growth and productivity. However, there is a lack of

evidence the use of fly-ash as soi I amendment. In this study, we examined the effect

of fly-ash application on changes in chemical properties and rice production on acid

sulphate soils.

2. Methodology

Fly-ash used for the experiment was collected from the Asam-asam Steam

Power Plant, South Kalimantan Province, Indonesia while soils for mixing with FA

were obtained from the Desa Tinggirian II Luar, Kecamatan Tamban, Kabupaten

Barito Kuala, South Kalimantan. Selected properties of acid sulphate ~oils used for

this study are presented in Table 1.

429

Six amendments ofF A, viz. 0 (100% soil), 5, 10, 20, 40 and 75 tones FA ha-1

were added homogenously to 6 kg of soils in pots of PVC and then incubated for 3

weeks. After 3 weeks soils in pots were sub-sampled and analyzed for pH,

exchangeable bases (Na, K, Ca dan Mg), mineral nitrogen, and available P. The

usual farm practice of transplantation of 20-30 days old seedlings, grown m a

separate seedbed, was done at three seedlings per pot. Rice plants were kept in

natural conditions and irrigated with tap water to maintain water-logged conditions

avoiding leakage of water from pots. All the growth and yield attributing characters

were studied after the harvesting period of 120 days. Plant height (em) was measured

by a metric scale and number of tillers was counted manually. After this, plant parts

were partitioned into roots, leaves, straw and grains and then were washed with

double distilled water. Root biomass (g pof1), straw weight (g pof1

) and total grain

weight (g pof1) were determined on oven-dried at 60 °C basis.

Table 1. Selected physical and chemical properties of acid sulphate soils used for the

study

Texture -Sand(%) 24.23 - Silt(%) 39.21 - Clay(%) 36.56

Bulk density (g cm'3) 0.55 pH (H20) 3.98 pH (KCil N) 3.67 Organic C (g C kg-1 soil) 27.67 Total nitrogen (g N kg-1 soil) 1.42 Exchangeable bases (cmol kg'1 soil)

- Na 0.13 -K 0.09 -Ca 4.51

0.14 -Mg

CEC (cmol kg-1 soil) 29.24

Total AI (mg kg-1) 1245.80

Total Fe (mg kg-1) 4916. 17

Total Mn (mg kg- I) 175.65

430

The ANOVA procedure of GenStat 1 l1h Edition (Payne, 2008) was used to

dctennine the effect of treatment on changes in the chemical properties and plant

growth and production. In the case of significance in ANOVAs, means were

compared by the Least Significant Difference (LSD) muluplc comparison procedure

at P<0.05.

3. Results and Discussion

Results of analysis of variance showed that soi l pH, mineral nitrogen content

and the concentration of exchangeable Ca were significantly affected by the addition

of fly-ash. In contrast, fly-ash application to acid sulphate soi ls did not change the

content of exchangeable -Na, -K and - Mg, and available P.

Soil reaction (soil pH) in the soil without fly-ash application was 5.08,

increased to 5.31 'J5.48 with the application fly-ash 5 40 tonnes ha· ' and increased

again to 5.62 with fly-ash application of75 tonnes ha· ' (Figure I). Increased soil pH

occurs because fly-ash containing CaO and MgO, which reacted with 1-t ions to

neutralize soil acidity. The !:,'Teater the amount of tly-ash application, the greater the

amount of CaO anq MgO are given into the soils, thus the greater the change m soil

pH. Kishor et al. (2009) reported that the neutralization capacity of fl y-ash ranged

from 0.01 to 3.74 meq per gram H30 +. [ncreasing the pH of the soil in paddy soils

treated with fly-ash was also reported in several other studies (Clark et al. , 2001;

Hyup et al., 2006; Swain et al. , 2007; Sajwan et al. , 2007).

0 .... I I 0..

6.00

5.75

5.50

5.25

5.00

4.75

4.50

c Qo

..>£

0 E ~

"' u QJ

:0 "' QJ no c "' ~ u )(

w

so

40 be

ab 30

a a a

20

10

0

c

0 5 10 20 40 75 0 5 10 20 40 75

Fly-ash application (ton ha·1) Fly-ash ap~lication (ton ha·1

)

Figure 1. Effect of fly-ash application on soil pH (left) and exchangeable-Ca (right). The

•

431

vertical bars represent standard deviation (n=3). Similar letters above columns indicate no

statistical difference between the treatments based on the LSD test at P <0.05.

Figure 1 also shows that the fly-ash application of 20 tonnes ha·1 yielded

exchangeable Ca that is not different from the soil without fl y-a h application.

However, when the amount of fly-ash application increased to 40 and 75 tonnes ha·1,

the concentration of exchangeable doubled than the soils without fly-ash application

(control), which only reached 15 cmol kg-1• Effect of coal ash on the exchangeable

Ca is due to the higher content CaO than the other cations (Na, K and Mg) of fly-ash,

so that when coal ash is added to soil, it will increase the availability of Ca in soils.

This is consistent with the study of Kishor et al. (2009) who reported that

exchangeable Ca is the most dominant cation in soils with fly-ash application.

Concentration of ammonium and nitrate decreased with an increase in the

amount of fly-ash application. Concentration of ammonium in the soil decreased

from 20.03 mg N kg-1 to 12. 15 mg N kg· 1 soil and concentration of nitrate decreased

from 63.61 mg N kg·1 soil to 42.83 mg N kg·1 soil with fly-ash application (Fig. 2).

These combinations resulted in reduction in total mineral nitrogen from 83.64 rng N

kg" 1 soil to 54.98 mg N kg-1 soil with the application of fly-ash (Figure 2). Decline in •

the mineral nitrogen with fly-ash application is due to increased gaseous N losses

through denitrification process with an increase in the amount of fly-ash application.

125 OAmmonium • Nitrat • Total mineral N

·o 100 Ill

.... c be bo

.::.'.

z bD

75 E

z 50 Iii ....

<11 c: 25 ~

0 0 5 10 20 40 75

Fly-ash application (ton ha·1)

432

Figure 2. Effect of fly-ash on mineral nitrogen. The vertical bars represent standard

deviation (n=3). Similar letters above columns indicate no statistical difference between the

treatments based on the LSD test at P <0.05.

Results of variance analysis showed that fly-ash application influenced

significantly the growth and production of rice. Fly-ash application of 5 and 10

tonnes ha·1 improved plant height from 78 em to 92-94 em. However, when the

amount of fly-ash application increased to 20-75 tonnes ha-1, plant height did not

show significant increases with subsequent increasing the amount of fly-ash

application (Figure 3). Similar results were obtained for the number of tiller

variable. Without the fly-ash application, the average number of tillers reached only

3 plants per pot. Number of tillers plants increased significantly to 7 plants per pot

with the fly-ash application at the rate 5-10 tonnes ha-1 (Figure 3).

Root dry weight of rice plants with fly-ash applications up to the level of 20

tonnes ha-1 is no different from that without fly-ash application. which is in the range

of 1.5 to 3.5 grams per pot (Figure 4). However, when the amount of fly-ash

application increased to 40 and 75 tonnes ha-1, root dry weight of rice plants ,

increased to 5 grams per pot (Figure 4). In contrast to the root dry weight, stems dry

weight of rice with the treatment of 5-20 tonnes ha·1 fly-ash application increased to

9-13 grams per pot from 3 grams per pot at the treatment of without fly-ash

application (Figure 4 ). The highest root dry weight of plants was observed in the

treatment of 40 and 75 tonnes ha-1 fly-ash application (Figure 4 ).

....

-.

433

125 10

be_ c c b c d d d

100 "' 8 E

u a a.

~ ~ 75 ~ 6 ..r:: a.• 0.0 Q) ~

..r:: 50 0 4 -..> c: ...._

"' Q)

..0 a... E 25 ::J 2 c

0 0 0 5 10 20 40 75 0 5 10 20 40 75

Fly-ash application (tonnes ha-1) Fly-ash application (tonnes ha-1)

Figure 3. Effect of fly-ash application in plant height (left) and number fo tillers (right). The

vertical bars represent standard deviation (n=3 ). Similar letters above columns

indicate no statistical difference between the treatments based on the LSD test atP <0_05.

~

.r: <>0 Qj 3 ~ -o ..... 0 0 cr:

6

5

4

3

2

1

0

ab ab a

a

b 20

b

16 d

c

12 b b

8

4 a

0

d

0 5 10 20 40 75 0 5 10 20 40 75

Fly-ash application (tonnes ha·1) Fly-ash application (tonnes ha-1)

Figure 4. Effect of fly-ash application on root dry weight (left) and stem dry weight (right).

The vertical bars represent standard deviation (n=3). Similar letters above

columns indicate no statistical difference between the treatments based on the

LSD test at P <0.05_

Rice production also increased by fly-ash application_ Grain dry weight of

rice without tly-ash applicatiOn IS 3.5 grams of pof ', increased more than 200%

( 11 .4 g pof1) with 5 tonnes ha-1 of t1y-ash application. When the amount of fly-ash

434

application increased to 20 tonncs ha·', grain dry weight increased by 280% ( 13.4 g

pof 1) . Moreover, there is an increase by 300% in the grain dry-weight ( 14.5 g pot- I)

with 75 tonnes ha·' of tly-ash appl ication (Figure 5).

Increases in the growth and production of rice were attributed to increasing the

amount of nitrogen, phosphorus and potassium absorbed by rice. Nitrogen uptake by

ri ce in the treatment of without fly-ash application was 84.39 mg N pof 1, increased

by I 6-38% with 5-75 tonnes ha·' of fly-ash application. Phosphorus and potassium

uptake by rice increased by 6-70% and 17-128%, respectively, with the similar

amount of fly-ash application (data not shown).

20

- 16 0 a. ~ 12

cd d d

b be

c 0

u 8 ~

"0 0 a .... a. 4 <lJ u

cr:: 0

0 5 10 20 40 75

Fly-ash application (tonnes ha·1)

Figure 5. Effect of fly-ash application on rice production. The vertical bars represent

standard deviation (n=3). Similar letters above columns indicate no statistical

difference between the treatments based on the LSD test at P <0.05.

Increase in nutnent uptake followed by increase in the growth and production

of rice may due to changes in the characteristics of the soil with the application of

fly-ash. The addition of fly-ash to soils accelerate the process of mineralization of

organic matter (Khan and Khan, 1996), thus increasing the availability of njtrogen.

Lee et al. (2007) in the study of changes in the availability of P in soils with 120

tonnes ha·' of fly-ash application in South Korea reported that the increase in Pin the

<:.0 ilc rlue" to the incre~se in the pH of the soil, incre::tsing the amount of silicate ::md

the additional P from coal ash. In this study, we also observed increases in soil pH

... -

...

435

from 4.43 at the treatment without fly-ash application to pH 5.22-5.41 with the fly­

ash application. Study conducted by Swain et al. (2007) also showed that the fly-ash

application increases the uptake ofN, P a:nd K by 106-149% .

-t. Conclusion and Implication

Observations on soil chemical properties after fly-ash application showed that

the addition of the fly-ash can increase the soi l pH, in which increased the amount of

fly-ash application to the soil will be followed by increases in soil pH. This result

implies that the fly-ash is potential to be used as an alternative lime for soil

improvement properties to increase biomass production. Results of the study

demonstrated that among the exchangeable cations observed, only exchangeable Ca

increased significantly with fly-ash application, indicating that fly-ash can be used as

a source of Ca for improvement of soil properties. The application of fly-ash also

increases the growth and yield of rice.

Acknowledgment

The authors acknowledged the Ministry of Education and Culture, the

Republic 9f Indonesia that was funded this study through the Competitive Grant of

Penelitian Unggulan Perguruan Tinggi 2015 .

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edition. John Willey & Sons, Inc., New York.

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Comberato, J.J., Vance, E.D., Someshwar, A. V. , 1997. Composition and land application of paper manufacturing residuals. ln: Rechcigl, J. , Mackinnon, H. (Eds.), Agricultural Uses of By-products and Wastes. ACS, Washington, DC, pp. 185-203.

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