International Seminar sustainable utilization of coastal resources in tropical zone, 19-20 October,2016, Bengkulu, Indonesia

Effect Of Ecological Factors On The Growth And Chlorophyll A Content Of Seaweed Kappaphycus alvarezii In Coral Reef Ecosystem (Seaweed Culture Potential in the Coral Reef Ecosystem) Rajuddin Syamsuddin1 Sri Mulyani2 Ambo Tuwo1 Jamaluddi Jompa1 1. Faculty of Marine Sciences and Fisheries, Hasanuddin University Kampus UNHAS Tamalanrea, Jl. Perintis Kemerdekaan, Km 10 Makassar, Indonesia HP. 081355565099; Email : [email protected] HP. 08124206391; Email : [email protected] HP. 08124230107; Email : [email protected] 2. Faculty of Agriculture, Bosowa University Jl. Perintis Kemerdekaan, Km 4 Makassar, Indonesia Email : [email protected]

ABSTRACT

The research objctives are to determine influence of several physical and chemical factors on the growth and chlorophyll a content of seaweed Kappaphycus alvarezii cultured in the coral reef. The study was conducted at Laikang Bay, Jeneponto Regency, Indonesia, applied floating raft culture method. The study was designed with Block Pattern Factorial. Row spacing and culture depth above the coral reef were the factors examined. Higher gowth rate and chlorophyll a of the seaweed was obtained at culture in 5 m above the coral reef compared with those cultured in culture 2 m above the coral reef. Higher growth rate and chlorophyll a content was also obtained at more tenuous spacing plants compared with those tighter spacing plants. Because of optimal sunlight intensity reach the thallus and better nutrients supply for the thallus absorption, the chlorophyll a content was higher at 30 cm row spacing than at 20 and 10 cm. Therefore, K. alvarezii can only be cultured in coral reef ecosystem at 5 depth with 30 cm row spacing applying floating raft method. Highest growth rate and chlorophyll a content was obtained at culture on the 5 m depth coral reef with 30 cm row spacing Multiple regression showed daily growth rate and chlorophyll a content was positively correlated wih light intensity, nitrate, ammonium, calcium, and magnesium concnetration, and negatively correlated with sedimentation. Key Words: Kappaphycus alvarezii, seaweed growth, chlorophyll a, water quality parameters, Coral reef

INTRODUCTION Marine waters of Indonesia is among the world best coral reefs region. reef functions as food supplier,

The coral

medical and other public services.

Coral reef of

Indonesia contribute 3.6 million tons fisheries production per year

with economic

benefict as much as US dollar 1.6 billion per year (Burke et.al.2002).

Seaweed

Kappaphycus alvarezii is among the fisheries production contribute income to fishermen as well as government source of income of

Indonesia. It is stated in Internasional

Seaweed Symposium in Bali that seaweed culture in coral reefs threats the ecosystem, even can cause the reef death.

However, there is no empirical accurate data regarding

the matter. Potential negative effect of seaweed culture on coral reef is blocking the sunlight penetration to the coral reef communities.

In addition, trapped silt and other particles

surrounding the cultured seaweed will in turn sunk and deposited as sediment dumped on the the coral reef, which threat the coral reef existence. Water depth of coral reef and spacing of cultured seaweeds 106

clump are factors influence sunlight penetration into the

International Seminar sustainable utilization of coastal resources in tropical zone, 19-20 October,2016, Bengkulu, Indonesia

waters and particles concentration which might influence both, the seeweed and the coral reef.

Both factors influence the growth rate and pigment synthesis (chlorophyll a

content) of seaweed, which is also part of seaweed biomass. For this reason, this piece of study was undertaken to analyse the nature of several ecological factors influence the growth and chlorophyll a content of K.alvarezii cultured within different depth of coral reefs with several row spacing.

MATERIALS AND METHODS The study was conducted at three spots of coral reef dominated by Acropora formosa at Laikang Bay, Jeneponto Residence, Province, Indonesia (Figure 1).

40 km south of Makassar, SouthS ulawesi

Floating

monoline

method

measuring 2m x 2m

was the K. alvarezii culture method applied.

Each culture unit was placed on the 2 m

and 5 m depth at each of coral reef spots.

Seaweed K. alverezii brown strain strain

(Figure 2) used was obtained from. fisherman cultivated at Laikang Bay Initial weight of each bond of seaweed seed is 50 gram. Blok pattern factorial was the experimental culture unit in different water depth seaweed

design applied.

Placement of seaweed

of coral reef (2 m and 5 m) and row spacing of

( 10 cm, 20 cm, and 30 cm) cultured were the factors examined. Two culture

periods with six weeks each designated as block, while placement of all combination of row spacing with water depth at three spots of coral reef designated as replicates. Therefore, there were 18 unit of seaweed culture, all were started and terminated at the same time.

107

International Seminar sustainable utilization of coastal resources in tropical zone, 19-20 October,2016, Bengkulu, Indonesia

Figure 1.

Map of experimental site ; Laikang Bay (above) reefs (below)

and the spot of coral

Figure 2. Sample of K. alvarezii used Weighing of each seaweed clumps was done weekly to obtain the weekly seaweed weight gain for six weeks culture period Daily growth rate further computed using the following formula (Hurtado et al, 2001) : DGR(% day-1) = Ln (Wt-W0)t-1 x 100 ; 108

International Seminar sustainable utilization of coastal resources in tropical zone, 19-20 October,2016, Bengkulu, Indonesia

DGR = Daily growth rate Wt = weight at t tim W0 = initial weight t = 7 days Insitu light intensity were measured weekly, concentration of nitrate, ammonium, and calcium (Tabel 1), chlorophyll a

and sediment were conducted at the Laboratory of

Research Center for Brackishwater Aquaculture, Takalar, Indonesia. Table 1. No 1 2 3 4

Method and instrument used for water quality parameter

measurement

Parameter Instrumen/Method Reference Amonia Spectrometric Strickland and Parsons (1972) Nitrat Spectrometric Strickland and Parsons (1972 Calsium Titrimetric Strickland and Parsons (1972 Light Intensity Lux Meter Sedimentation rate was determined using Sediment Trap and computed with the

following formula : Wieght of accumulated sediment = WL-1T-1 ; W = dry weight of sediment (mg) L = surface area of the sediment trap (cm2) T = time of sediment trap placement (day) Chlorophyll a content of thallus was determined applying the method of Arnon (1949, cited by Thiruaran and Anantharaman, 2009) with the following formula : Chlorophyll a (mg/g) = 12,7 x A663 – 2,69 x A645(a x 1000 x W)-1V ; A = Absorbant at each wave length V = Volume of solvent (ml) a = Volume of dilutioon (ml) W= weight of seaweed thallus (g) The signicance of treatments influence on the growth and chlorophyll a content of K. alvarezii was statistically analysed using Analysis of Variance (ANOVA) continued with HSD Tukey Test (Steel and Torrie, 1980). Relationship of seaweed growth and chlorophyll a content with the measured environmental factors was analysed applying Backward Methode Multiple Regression Analisis (Steel and Torrie, 1980).

RESULTS AND DISCUSSION Analysis of variance showed that there was none significant influence of interaction between coral reef water depth with row spacing of seaweed clamps on the seaweed growth (P =

0.873) and chlorophyll a content (P =

0.879) of K. alvarezii.

Row

spacing and water depth were singly significantly influence the seaweed growth and 109

International Seminar sustainable utilization of coastal resources in tropical zone, 19-20 October,2016, Bengkulu, Indonesia

chlorophyll a contentof K. alvarezii. HSD Tukey Test showed that average daily growth rate of the seaweed at row spacing of 30 cm (3.97 % day-1) was significantly higher compared with those grown at row spacing of 10 cm (3.75 % day-1), while growth rate at row spacing of 20 cm (3.86 % day-1) was not significantly different with the growth rate at 10 cm (Table 2). HSD Tukey Test showed that highest average chlorophyll a content thallus) of the

seaweed was recorded at row spacing of 30 cm followed by chlorophyll a

content of seaweed grown at 20 cm (0.0077 mg g-1 g-1

(0,0080 mg g -1

thallus) and at

10 cm (0,0073 mg

thallus) (Table 3).

Table 2. Average of daily growth rate (%day-1) of seaweed K. alvarezii grown at different row spacing and the result of HSD Tukey Test Row spacing (cm) Average±SD 10 3.75± 0.05a 20 3.86± 0.05ab 30 3.97 ± 0.05b Averages with the same letter are not significantly different (α = 0,05). Table 3.Average chlorophyll a content (mg g -1 thallus) of seaweed K. alvarezii grown at different row spacing and the result of HSD Tukey Test Row spacing (cm) Average±SD 10 0.0073a 20 0.0077b 30 0.0080c Averages with the same letter are not significantly different (α = 0,05). Daily growth rate and chlorophyll a content of K.alvarezii increase with increasing the coral reef water depth at all level of tried row spacings (Table 4 and Table 5, respectively). Average daily growth rate (% day-1) of K.alvarezii grown at different row spacing and water depth Water depth (m) Row spacing (cm) 2 5 10 3.47 4.02 20 3.57 4.16 30 3.71 4.23

Table 4.

Average chlorophyll a content (mg g -1 thallus) grown at different row spacing and water depth Water depth (m) Row spacing (cm) 2 5 10 0.007 0.008

Table 5.

110

of seaweed K. alvarezii

International Seminar sustainable utilization of coastal resources in tropical zone, 19-20 October,2016, Bengkulu, Indonesia

20 30

0.007 0.007

0.008 0.009

Highest growth rate (4.23% day-1) was recorded at 5 m depth coral reef with 30 cm row spacing of seaweed clamps, chlorophyll a content (0.009 mg g -1 30 cm row spacing,

lowest (3.47% day-1) at 2 m coral reef. thallus)

lowest (0.008 mg g-1

Highest

was recorded at 5 m depth coral reef with thallus) at 2 m reef with 10 cm and 20 cm

row spacing. Daily growth rate of K.alvarezii obtained in this study relatively equal with recorded by Munoz et al (2004) (2.0-8.1% day-1), Hurtado et al. (2008) (1.1-4.0% day-1) and Thirumaran and Anatharaman (2009)(2.33-5.22% day-1). Relatively higher growth rate of K.alvarezii grown at 5 m depth coral reef compared with those grown at 2 m depth coral reef due to the influence of sedimentation rate which was lower (25.88 mg cm-2 day-1) at 5 m depth coral reef compared with higher sedimentation rate (39.51 mg cm-2 day-1)

at 2 m depth coral reef.

Sediment at 2 m

depth coral reef was easily stirred up by water movement so that high amount of silt particles stick on the thallus surface of seaweed grown in this particular waters. Relatively lower sedimentation rate at 5 m depth coral reef cause lower amount of silt particles stick on the seaweed thallus grown at this particular portion of coral reef. Higher growth rate and chlorophyll a content occurred at more tenuous row spacing (30 cm) could be attributed to better water movement surround the seaweed clamps which dissolve nutrients then absorbed by the seaweeds for the growth and chlorophyll a synthesis.

Besides, competition in nutrients absorption among the plant clamps was

lower compared with tighter row spacing (10 cm and 20 cm).

Less amount of silt

particles stick on the thallus surface at tenuous row spacing compared with tighter row spacing also cause higher growth rate and chlorophyll a content of the plant. less amount of silt particles stick on thallus surface,

Because of

more light energy exposed to the

thallus surface and more nutrients diffused into the seaweed thallus cause higher growth rate and chlorophyll a content

of the plant with more tenuous row spacing.

Multiple Regression showed that growth rate of the plant positively correlated with light intensity, concentrations of nitrogen (nitrate and ammonium), and calcium, and negatively with sedimentation rate.

The correlation showed in the following equation :

Y = 0.566 -0.014sedimentation rate + 0.140nitrate concentraion + 2.193amonium concentration + 0.04 calsium concentration Y independent variable (growth rate) was 86% determined by those environmental 111

International Seminar sustainable utilization of coastal resources in tropical zone, 19-20 October,2016, Bengkulu, Indonesia

parameters (R2=

0,86).

Relatively closer realationship shown by ammonium

concentration (r=0.87), calcium concentration (r=0.74), and sedimentation rate (r= -69). This indicated that contribution of ammonium as nitrogen sources in metabolism of the seaweed in this coral reef greater than other forms of nitrogen.

In submerged soils

(coral reef sediment is included), ammonium is the mineralization product of organic nitrogen (Ponnamperuma, 1977).

Nitrogen compounds are transported by silt

during

sedimentation (Golterman, 1975).

The sediments absorb and store nutrients and release

them as they are needed by algae (Gruending, 1975). Multiple regression analysis showed that chlorophyll a content of the seaweed was positively influenced by light intensity, negatively correlated with sedimentation rate, and positively related with concentrations of ammonium and calcium.

The regression

equation is as follows : Y = -0.003 + 2.96(10-7)light intensity– 2.5(10-5)sedimentation rate + 0.003ammmnium concentration + 1.08(10-8)calsium concentration The chlorophyll a content was 90% determined (influenced) by factors of light intensity sedimentation, as well as concentrations of ammonium and calcium

(R 2=

0.90). Light energy is essential for chlorophyll a synthesis (Sallisbury and Ross, 1969). Light intensity exposed to the thallus surface was 3242 lux – 4119 lux.

The range of light

intensity could stimulate the seaweed growth as long as it was not exceed 12,000 lux (Isnansetyo dan Kurniastuty, 1995). 8910 lux (equal

K. alvarezii can grow with light intensity 7830 -

with 145-165 µmol m-2s-1) in the laboratory (Dawes , 1979

in SEAPlantNet, 2005). Different sedimentation rate at different location of seaweed culture (between the 2 m water depth with 5 depth) cause difference of thallus surface area covered by silt particles, which in turn different nutrient and light energy absorbed by seaweed thallus. of sedimentation rate was 13.82 – 66.16 mg cm-2 day-1.

Range

The energy requiring process,

active ion (plant nutrient) uptake increases with rising level of illumination (Kuhl, 1962). Ion transport is light dependent (Soeder and Stengel, 1974) Nitrogen is highly important in determinant of the productivity of algae (Prescott, 1968).

Nitrogen is essential for seaweed growth; for cell division and protoplasm

construction.

In photosynhthesis, nitrogen may function in pigment (chlorophyll a)

conctruction (Prescott, 1968 ; Lawlor, 1993; Sutedjo, 2008).

Increased chlorophyll a

levels lead to increased photosynthesis and thus increased biomass production of plants (Jadid, 2008). 112

International Seminar sustainable utilization of coastal resources in tropical zone, 19-20 October,2016, Bengkulu, Indonesia

Recorded nitrate concentrations (0.75 – 2.39 ppm) was suitable for seaweed growth (Andarias, 1977; Kapraun, 1978: Effendi, 2003; Zatnika, 2009), although the nitrate concentration exceed 0.1 ppm of natural waters in general (Effendi, 2003) due to nitrate disposal of antropogenic (sedimentation) influence. Recorded ammonium concentrations (0.23 – 0.64 ppm) was suitable for seaweed growth (Kapraun, 1978).

Relationship of growth rate as well as chlorophyll a content

of the seaweed with ammonium was closer than nitrate indicated that ammonium absorption by the plant was higher than with nitrate (Wheeler dan Srivastava, 1984). Ammonia is the form in which nitrogen enters the metabolic process.

Nitrate is reduced

to ammonia before being incorporated into organic compounds (Syrett, 1962). High calsium concentration (888.87 – 999.01 ppm) of water in coral reef (study site) is factor influence seaweed photosynthesis, the building block of cell wall, and thallus strengthening.

Calcium role as enzim activator (included activator of growth enzyme),

nutrient transport,

and increasing resistant to diseases (Salisbury and Ross, 1969).

CONCLUSION Light intensity and several essential nutrient in study site was in optimal range for K.alvarezii growth and chlorophyll a synthesis. rate which was different

However, occurrence of sedimentation

between in the 5 m depth coral reef with those in the 2 m depth

coral reef cause the diferent on surface area of thallus covered by silt particles which in turn the different in nutrient and and light absorption. Growth rate and chlorophyll a content of K.alvarezii tend to increase along with increasing water depth and tenous row spacing. least 30 cm spacing.

Highest at 5 m depth coral reef with at

Culturing K.alvarezii at this depth of coral reef and such row

spacing could possibly able to preserve the coral reefs. Recorded growth of K.alvarezii was relatively as high as those obtained by several researchers who were conducted research on K.alvarezii with the same method outside coral reef waters.

REFERENCES

Andarias, I. 1977. Prospek Pengembangan Budidaya Rumput Laut dalam Menyongsong Era Globalisasi dalam Bidang Budidaya Perairan. Laporan Penelitian. Fakultas Ilmu Kelautan dan Perikanan. Uniersitas Hasanuddin Makassar Burke L., E. Selig and M. Spalding. 2002. Terumbu Karang Yang Terancam Di Asia Tenggara Diterjemahkan Dari Reef at Risk in South East Asia. World Resources Institute. Washington DC.USA 113

International Seminar sustainable utilization of coastal resources in tropical zone, 19-20 October,2016, Bengkulu, Indonesia

Effendi, H. 2003. Telaah Kualitas Air Bagi Pengelolaan Sumberdaya Dan Lingkungan Perairan. Kanisius. Yogyakarta. Golterman, H.C. 1975. Chemistry. In : Whitton, B.A. (Ed.). 1975. River ecology. Studies in ecology, Vol. 2: 81-105 Gruending, G.K. 1975. Ecology of epipelic communities in Modia Lake. British Columbia. J. of Phycol., 7(3):239-249 Hurtado, A.Q., R.F. Agbayan, R. Sanares, and M.R.de Castro-Mallare. 2001. The Seasonality and Economic Feasibility of Cultivating Kappaphycus alvarezii in Panagatan, Cays, Caluya, Antique, Philippines. Elsevier. Aquaculture, 199:295-310. Hurtado, A. Q., A. T. A. Crithchley. Trespoey and G. Bleicher-Lhonneur. 2008. Growth and Carrageenan Quality of Kappaphycus striatum var. Sacol Grown at Different Stocking Densities, Duration of Culture and Depth. J. Appl. Phycol, 20: 551-555. Isnansetyo, A., dan Kurniastuty. 1995. Teknik Kultur Phytoplankton, zooplankton, Pakan Alami untuk Pembenihan Organism Laut. Kanisius. Jogjakarta. Jadid, N. 2008. Media Kultur Jaringan. http:www.seribd.com. 17 p. Kapraun, D.F. 1978. Field and Culture Studies on Selected North Carolina Polysiphonia. Botany Marine, 11:143-1 Kuhl, A. 1962. Inorganic phosphorous uptake an metabolism. In : Lewin, R.A. 1962. Physiology and biochemistry of alge. Acad.Press. New York. Pp. 211-230. Lawlor, D. W. 1993. Photosynthesis. 2nd Edition. Longman Group UK Limited. London. pp. 9-23 Munoz J., Y. Freile-Pelegrin, Y., and D. Robledo. 2004. Marine Culture of Kappaphycus alvarezii (Rhodophyta, Solieriaceae) Color Strains In Tropical Waters of Yucatan, Mėxico. Aquaculture, 239:161-171. Ponnamperuma, F.N. 1977. The physico-chemical properties of submerged soils in relation to fertility. IRPS. No.5. IRRI, Los Banos, Philippines. Prescott, G.W. 1968. The algae; A review. Houghton, Miflin Co. Boston. 430p. Salisbury, F.K. and C. Ross. 1969. Plant physiology. Wadsworth Publ. Co. Inc. Belmon. California. 764p. Soeder, C.J. and C.J. Stengel. 1974. Physico-chemical factors affecting metabolism and growth rate In: Stewart, W.D.P. (Ed.). 1974. Algal Physiology and biochemistry. Blakc Steel, R. G. and J. H. Torrie. 1980. Principles and Procedures of Statistic. McGraw – Hill Book Co. New York. Strickland, J.D.H. and T.R. Parsons. 1972. A Practical Handbook of Sea Water Analysis. Bull. Of Fish. Res. Board of Canada. Sutedjo, M. M, 2008. Pupuk dan Cara Pemupukan. Rineta Cipta. Jakarta Syrett, P.J. 1962. Nitrogen assimilation. In: Lewin, R.A. (Ed.). 1962. Physiology and biochemistry of algae. Acad. Press. New York. Pp. 171-188 Thiruaran dan Anantharaman, 2009 Thirumaran,G. and P. Anantharaman. 2009. Daily Growt Rate of Field Farming Seaweed Kappaphycus alvarezii (Doty) Doty ex P. silva in Vellar Estuary. World Journal of Fish and Marine Sciences, 1 (3): 144-153. Wheeler, W.N. and L.M. Srivastata. 1984. Seasonal Nitrate Physiology of Macrocystis integrifolia Bory.J.Exp. Mar.Biol.Ecol. 76:35-50 Zatnika, A. 2009. Pedoman Teknis Budidaya Rumput Laut. Badan Pengkajian dan Penerapan Teknologi, Jakarta.

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