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Staff Publications

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    'Staff publications' is the digital repository of Wageningen University & Research

    'Staff publications' contains references to publications authored by Wageningen University staff from 1976 onward.

    Publications authored by the staff of the Research Institutes are available from 1995 onwards.

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    Effect of Three Types of Liquid Compost Combined with Avicennia marina Leaves on Growth and Survival of Tiger Prawns (Penaeus monodon)
    Ariyati, Restiana W. ; Rejeki, Sri ; Widowati, Lestari Lakhsmi ; Elfitasari, Tita ; Bosma, R.H. - \ 2019
    The Impact of Aquaculture Field School Training on the Shrimp and Milkfish Yield and Income of Farmers in Demak, Central Java
    Bosma, R.H. ; Wisnu Ariyati, Restiana ; Rejeki, Sri ; Widowati, Lestari Lakhsmi - \ 2019
    Impact of a Low External Input Approach on Yields of Brackish Water Shrimp Ponds in Indonesia
    Rejeki, Sri ; Wisnu Ariyati, Restiana ; Widowati, Lestari Lakhsmi ; Bosma, R.H. - \ 2019
    In: Book of abstracts of the 12th Asian Fisheries & Aquaculture Forum (AFAF). -
    In Indonesia, destruction of mangrove forest for ponds, ground-water extraction and climate change resulted in loss of land and yield' reductions. Farmers in Demak harvested 200 and 43 kg/ha/year of milkfish and shrimp, respectively. Demak's Building with Nature project uses Aquaculture Field Schools to train farmers in Low External Input and Sustainable Aquaculture (LEISA) that applies compost and a home-made organic fertiliser called MOL. Our team monitored the yield and others factors in three of the ten villages. Average yields of farmers applying MOL and cultivating both milkfish and shrimp increased to about 700 kg/ha and 260 kg/ha, respectively. Farmers having small multi-species ponds made 3 times higher operational cost and reached slightly lower gross margins than those with larger. LEISA increased cost and lead to slightly higher yields, but because most farmers applying MOL successfully stocked shrimp their income was almost double: 11.3 compared to 22 million IDR/ha/yr.
    The role of seaweed (Gracilaria sp) and green mussel (Perna viridis) in reducing organic waste in shrimp culture water
    Widowati, Lestari Lakhsmi ; Prayitno, S.B. ; Rejeki, Sri ; Elfitasari, Tita ; Wisnu Ariyati, Restiana ; Bosma, R.H. - \ 2019
    In: Book of abstracts of the 12th Asian Fisheries & Aquaculture Forum (AFAF). - - p. 75 - 75.
    Organic waste, originating from inlet water, feed or excrements, reduces the water quality in brackish water pond used for aquaculture of e.g. shrimp. High concentrations of organic waste are a threat to ecosystem stability since decomposition reduces dissolved oxygen content, and can result in toxic compounds such as ammonia and nitrite. Various aquaculture technologies can reduce the concentration of organic waste or prevent the consequences of its decomposition. Two options .are the use of seaweed and green mussel since these organisms use organic and an-organic particles for their nutrition. This research aims to analyse the impact of seaweed and green mussle densities in reducing organic waste in shrimp culture water. Tt:iis research was done in Tambakbulusan, Demak regency, Central Java, lndone'sia. Densities of seaweed (Gracilaria verucosa) and green mussel (Perva viridis), were compared in a randomized block design of 9 treatments and 4 replications. Densities for seaweed treatments were 50, 100, 150 and 200 gram m-2, while treatments for green mussel were 60, 90, 120 and 150 gram m-2. Both seaweed and mussels were hanged on rope in fiber tanks of 1 x1 x1 m with 800 L of brackish water and substrate to create a brackish mesocosm. The densities of seaweed and green mussle influenced organic waste reduction. The optimum seaweed density was 100 g m-2 and reduced ammonia with 34% and nitrite with 24%. The higher densities of seaweed resulted in concentration of nitrate lower than advised for shrimp culture (0.36 mg.m-2). The highest densities of green mussel increased the content of organic matter and nitrite compared to the control. The green mussel density of 90 g.m-2 gave the highest absorption of organic matter (38%) and nitrate (49%).
    The effects of decomposing mangrove leaf litter and its tannins on the water quality, growth and survival of tiger prawn (Penaeus monodon) post-larvae
    Rejeki, Sri ; Middelians, Marcel ; Widowati, Lestari Lakhsmi ; Wisnu Ariyati, Restiana ; Bosma, R.H. - \ 2019
    In: Book of abstracts of the 12th Asian Fisheries & Aquaculture Forum (AFAF). - - p. 81 - 81.
    Prawn farming in Demak, Indonesia is often practiced in silvo-aquaculture systems; mostly mangrove trees are planted on pond bunds. Mangrove leaves or its substrates may impact prawn. Mangrove regrowth in new habitats usually starts with Avicennia marina (AM) while planting is mostly done with Rhizophora
    apiculata (RA). We compared the effects of decomposing fresh leaves of AM and
    RA, on water quality and performance of Penaeus monodon post larvae (PL).
    Hundred PL21 (0.28 g) were stocked in each of 33 aerated tanks, with 800L
    brackish water, assigned to triplicates of six concentrations (g/L) of both species
    leaves: 0 (control), 0.125, 0.25, 0.5, 0.125 minced leave and 0.125 leachate of
    minced leaves. The PL were fed 3x daily with pellets at 10% of initial total body
    weight. Temperature, salinity, DO and pH were recorded daily. Tannin, H2S and
    NH3-N concentrations were measured every ten days. After 37 days, prawn's body weights (BW) were measured, and specific growth rate (SGR, %/day) and survival rates (SR, %) calculated. Results were analysed with ANOVA and Pearson's
    correlation. Leaf concentrations had no effect on DO, H2S, non-significantly
    effected pH and SR, but significantly effected tannin, NH3-N and SGR. SR varied
    from 62±14 to 70±8, and SGR between 1.5 to 2.1. The correlation of BW with SR
    for both AM and RA was highly significantly negative (-0.7), thus obscuring potential effects of tannin, NH3-N, and species. As feeding levels were not adjusted, prawn probably fed on both dead and molting prawn. Tannin concentrations in the water fluctuated around 2 mg/L, while in green leaves of RA and AM these were 2.2 ±0.9 and 1.6 ±0.4, respectively. NH3-N increased from 0.67 to levels up to 0.99 mg/L making decomposing mangrove leaves of AM and RA toxic for prawn in tanks without water exchange.
    Effect of stocking density on the survival rate and grow-out of blue swimming crab (Portunus pelagicus) in brackish water ponds
    Wisnu Ariyati, Restiana ; Rejeki, Sri ; Bosma, R.H. ; Schrama, J.W. - \ 2019
    In: Book of abstracts of the 12th Asian Fisheries & Aquaculture Forum (AFAF). - - p. 76 - 76.
    Crabs only contribute a small percentage to Indonesia's total exports of aquaticproducts. Due to the growing popularity of the Blue swimming crab (Portunuspelagicus ), fishery catches of this species have increased since the early 1950s.This increased fishing pressure has led to a decline in the P. pelagicus population in Southeast Asian countries such as Thailand, Philippines, Vietnam and Indonesia. As a result, fishermen hardly catch large crab, and market also juveniles. Juvenile crabs are usually sold at lower prices; therefore, fattening small crab to market size may have a future. Furthermore, fattening to marketable size for an acceptable cost and effort might also reduce the fishing pressure. This study aimed to determine the optimal stocking density of Blue swimming crab for rearing in cages in shallow brackish water ponds. The research was conducted at Tambakbulusan village, Demak, Central Java, Indonesia. In a pond with 0.5 meter water depth we suspended 20 cages of 2.5 x 2 meter, for a Randomized Block Design of 4 stocking densities (2, 3, 4, and 5 individual's m-2) in five replications. Sea weed was added as shelter. The initial average size of these crabs was 5+1.6 cm in carapace length and 20+1.5 g in body weight. The crabs were fed trash-fish twice a day at a total dosage of 5 % of body weight; the quantity was adjusted bi-weekly after measuring and weighing all individuals. The effect of stocking density on the growth was not significantly different (P>0.05) but the survival rate was (P<0.05). Lowest densities (2 individual's m-2) resulted in highest survival rate (50 %). Research is needed oncauses and solutions for mortality as survival seems to be the most limiting factor for a feasible grow-out farming of Blue swimming crab.
    Assessing Constraints to Innovations in the Indonesian Aquaculture Value Chain
    Elfitasari, Tita ; Klerxk, Laurens ; Joffre, O.M. ; Rejeki, Sri ; Widowati, Lestari Lakhsmi ; Wisnu Ariyati, Restiana ; Bosma, R.H. - \ 2019
    In: Book of Abstracts of the 12th Asian Fisheries & Aquaculture Forum (AFAF). - - p. 317 - 317.
    In Indonesia, destruction of mangroves for ponds, ground-water extraction and climate change result in loss of land and livelihoods since 2008. In Demak (Central Java) and Brebes (West Java) most farmers stopped stocking shrimp, also as water quality had reduced due to industrial and urban waste. Integrated Multi Trophic aquaculture (IMTA) might recover shrimp aquaculture. Data on the innovations in the value chain of shrimp were collected and analysed using the RAAIS tool (Schut et al. 2015; Agricultural Systems 132: 1–112). Stakeholders from different background participated.

    Participants agreed that most constraints were institutional, often related to infrastructure and assets, and rooted in laws and regulations at the national level. Among the top three constraints one constraint was similar: the lack of extension services. The adoption of IMTA and other innovations in the mangrove restoration areas of Brebes and Demak regency thus face mostly similar challenges.
    PASMI designs Aquaculture to Support Mangrove Restoration in Indonesia
    Ariyati, Restiana ; Widowati, Lestari L. ; Rejeki, Sri ; Elfitasari, T. ; Bosma, R.H. - \ 2019
    - 1 p.
    Wageningen Indonesian Scientific Exposure (WISE) 2019
    Wisnu Ariyati, Restiana ; Widowati, Lestari Lakhsmi ; Rejeki, Sri ; Elfitasari, T. ; Bosma, Roel - \ 2019

    Impact of a Low External Input Approach on Yields of Brackish Water Shrimp Ponds in Indonesia
    Rejeki, Sri ; Wisnu Ariyati, Restiana ; Widowati, Lestari Lakhsmi ; Bosma, Roel - \ 2019
    In Indonesia, destruction of mangrove forest for ponds, ground-water extraction and climate change resulted in loss of land and yield' reductions. Farmers in Demak harvested 200 and 43 kg/ha/year of milkfish and shrimp, respectively. Demak's Building with Nature project uses Aquaculture Field Schools to train farmers in Low External Input and Sustainable Aquaculture (LEISA) that applies compost and a home-made organic fertiliser called MOL. Our team monitored the yield and others factors in three of the ten villages.
    Average yields of farmers applying MOL and cultivating both milkfish and shrimp increased to about 700 kg/ha and 260 kg/ha, respectively. Farmers having small multi-species ponds made 3 times higher operational cost and reached slightly lower gross margins than those with larger. LEISA increased cost and lead to slightly higher yields, but because most farmers applying MOL successfully stocked shrimp their income was almost double: 11.3 compared to 22 million IDR/ha/yr.
    The Impact of Aquaculture Field School Training on the Shrimp and Milkfish Yield and Income of Farmers in Demak, Central Java
    Bosma, Roel ; Wisnu Ariyati, Restiana ; Rejeki, Sri ; Widowati, Lestari Lakhsmi - \ 2019
    The role of seaweed (Gracilaria sp) and green mussel (Perna viridis) in reducing organic waste in shrimp culture water
    Widowati, Lestari Lakhsmi ; Prayitno, S.B. ; Rejeki, Sri ; Elfitasari, Tita ; Wisnu Ariyati, Restiana ; Bosma, Roel - \ 2019
    Organic waste, originating from inlet water, feed or excrements, reduces the water quality in brackish water pond used for aquaculture of e.g. shrimp. High concentrations of organic waste are a threat to ecosystem stability since decomposition reduces dissolved oxygen content, and can result in toxic compounds such as ammonia and nitrite. Various aquaculture technologies can reduce the concentration of organic waste or prevent the consequences of its decomposition. Two options .are the use of seaweed and green mussel since these organisms use organic and an-organic particles for their nutrition. This research aims to analyse the impact of seaweed and green mussle densities in reducing organic waste in shrimp culture water. Tt:iis research was done in Tambakbulusan, Demak regency, Central Java, lndone'sia. Densities of seaweed (Gracilaria verucosa) and green mussel (Perva viridis), were compared in a randomized block design of 9 treatments and 4 replications. Densities for seaweed treatments were 50, 100, 150 and 200 gram m-2, while treatments for green mussel were 60, 90, 120 and 150 gram m-2. Both seaweed and mussels were hanged on rope in fiber tanks of 1 x1 x1 m with 800 L of brackish water and substrate to create a brackish mesocosm. The densities of seaweed and green mussle influenced organic waste reduction. The optimum seaweed density was 100 g m-2 and reduced ammonia with 34% and nitrite with 24%. The higher densities of seaweed resulted in concentration of nitrate lower than advised for shrimp culture (0.36 mg.m-2). The highest densities of green mussel increased the content of organic matter and nitrite compared to the control. The green mussel density of 90 g.m-2 gave
    The effects of decomposing mangrove leaf litter and its tannins on the water quality, growth and survival of tiger prawn (Penaeus monodon) post-larvae
    Rejeki, Sri ; Middelians, Marcel ; Widowati, Lestari Lakhsmi ; Wisnu Ariyati, Restiana ; Bosma, Roel - \ 2019
    Prawn farming in Demak, Indonesia is often practiced in silvo-aquaculture systems; mostly mangrove trees are planted on pond bunds. Mangrove leaves or its substrates may impact prawn. Mangrove regrowth in new habitats usually starts with Avicennia marina (AM) while planting is mostly done with Rhizophora
    apiculata (RA). We compared the effects of decomposing fresh leaves of AM and
    RA, on water quality and performance of Penaeus monodon post larvae (PL).
    Hundred PL21 (0.28 g) were stocked in each of 33 aerated tanks, with 800L
    brackish water, assigned to triplicates of six concentrations (g/L) of both species
    leaves: 0 (control), 0.125, 0.25, 0.5, 0.125 minced leave and 0.125 leachate of
    minced leaves. The PL were fed 3x daily with pellets at 10% of initial total body
    weight. Temperature, salinity, DO and pH were recorded daily. Tannin, H2S and
    NH3-N concentrations were measured every ten days. After 37 days, prawn's body weights (BW) were measured, and specific growth rate (SGR, %/day) and survival rates (SR, %) calculated. Results were analysed with ANOVA and Pearson's
    correlation. Leaf concentrations had no effect on DO, H2S, non-significantly
    effected pH and SR, but significantly effected tannin, NH3-N and SGR. SR varied
    from 62±14 to 70±8, and SGR between 1.5 to 2.1. The correlation of BW with SR
    for both AM and RA was highly significantly negative (-0.7), thus obscuring potential effects of tannin, NH3-N, and species. As feeding levels were not adjusted, prawn probably fed on both dead and molting prawn. Tannin concentrations in the water fluctuated around 2 mg/L, while in green leaves of RA and AM these were 2.2 ±0.9 and 1.6 ±0.4, respectively. NH3-N increased from 0.67 to levels up to 0.99 mg/L making decomposing mangrove leaves of AM and RA toxic for prawn in tanks without water exchange.
    Effect of stocking density on the survival rate and grow-out of blue swimming crab (Portunus pelagicus) in brackish water ponds
    Wisnu Ariyati, Restiana ; Rejeki, Sri ; Bosma, Roel ; Schrama, Johan - \ 2019
    Crabs only contribute a small percentage to Indonesia's total exports of aquatic products. Due to the growing popularity of the Blue swimming crab (Portunus pelagicus ), fishery catches of this species have increased since the early 1950s. This increased fishing pressure has led to a decline in the P. pelagicus population in Southeast Asian countries such as Thailand, Philippines, Vietnam and Indonesia. As a result, fishermen hardly catch large crab, and market also juveniles. Juvenile crabs are usually sold at lower prices; therefore, fattening small crab to market size may have a future. Furthermore, fattening to marketable size for an acceptable cost and effort might also reduce the fishing pressure. This study aimed to determine the optimal stocking density of Blue swimming crab for rearing in cages in shallow brackish water ponds. The research was conducted at Tambakbulusan village, Demak, Central Java, Indonesia. In a pond with 0.5 meter water depth we suspended 20 cages of 2.5 x 2 meter, for a Randomized Block Design of 4 stocking densities (2, 3, 4, and 5 individual's m-2) in five replications. Sea weed was added as shelter. The initial average size of these crabs was 5+1.6 cm in carapace length and 20+1.5 g in body weight. The crabs were fed trash-fish twice a day at a total dosage of 5 % of body weight; the quantity was adjusted bi-weekly after measuring and weighing all individuals. The effect of stocking density on the growth was not significantly different (P>0.05) but the survival rate was (P<0.05). Lowest densities (2 individual's m-2) resulted in highest survival rate (50 %). Research is needed on causes and solutions for mortality as survival seems to be the most limiting factor for a feasible grow-out farming of Blue swimming crab.
    Assessing Constraints to Innovations in the Indonesian Aquaculture Value Chain
    Elfitasari, Tita ; Klerxk, Laurens ; Joffre, Olivier ; Rejeki, Sri ; Widowati, Lestari Lakhsmi ; Wisnu Ariyati, Restiana ; Bosma, Roel - \ 2019
    In Indonesia, destruction of mangroves for ponds, ground-water extraction and climate change result in loss of land and livelihoods since 2008. In Demak (Central Java) and Brebes (West Java) most farmers stopped stocking shrimp, also as water quality had reduced due to industrial and urban waste. Integrated Multi Trophic aquaculture (IMTA) might recover shrimp aquaculture. Data on the innovations in the value chain of shrimp were collected and analysed using the RAAIS tool (Schut et al. 2015; Agricultural Systems 132: 1–112). Stakeholders from different background participated.

    Participants agreed that most constraints were institutional, often related to infrastructure and assets, and rooted in laws and regulations at the national level. Among the top three constraints one constraint was similar: the lack of extension services. The adoption of IMTA and other innovations in the mangrove restoration areas of Brebes and Demak regency thus face mostly similar challenges.
    The Role of Seaweed (Gracilaria verucosa ) and Green Mussel (Perna viridis) in Reducing Organic Waste in Shrimp Culture
    Widowati, Lestari Lakhsmi ; Prayitno, S.B. ; Rejeki, Sri ; Elfitasari, Tita ; Wisnu Ariyati, Restiana ; Bosma, Roel - \ 2019
    Effect of three types of liquid compost combined with Avicennia marina leaves on growth and survival of tiger prawns (Penaeus monodon)
    Ariyati, Restiana ; Rejeki, Sri ; Widowati, Lestari Lakhsmi ; Elfitasari, Tita ; Bosma, Roel - \ 2019
    Correction to: Effect of three types of liquid compost combined with Avicennia marina leaves on growth and survival of tiger prawns (Penaeus monodon)
    Ariyati, Restiana Wisnu ; Rejeki, Sri ; Widowati, Lestari L. ; Elfitasari, Tita ; Bosma, Roel H. - \ 2019
    International Aquatic Research 11 (2019)4. - ISSN 2008-4935 - p. 323 - 324.

    Due to the author’s omission to check the corrections by the journal’ imposed reviewer of English style. Please read the following sections and Tables as follows: Abstract The sustainability of prawn farming in brackish water ponds is controversial because of low yields and mangrove clearing. Low yields are due mostly to insufficient preparation of pond bottoms. Mangrove trees are often planted on pond bunds as window dressing. This study examined the effect of three types of liquid compost from vegetables, fruit, and both vegetables and fruit in tanks to which whole or chopped Avicenia marina leaves were added to mimic local pond conditions. In a split-plot design, 28 square tanks were each stocked with one hundred 15-day-old post-larvae tiger prawns (Penaeus monodon). Four tanks were used as controls and 24 were assigned to the treatments, 12 with whole and 12 with chopped leaves. In both of these 12, 4 received liquid compost from vegetables, 4 from fruits and 4 from their mixture. Shrimp were weighed at the start, halfway and end of the 50-day trial, and fed at 5% of the estimated total weight; survival was counted at the end. The survival rates of treatments and controls (65–76%) were not significantly different. Shrimp in water with vegetable compost grew significantly faster (2.7% day-1) than in both treatments with fruit (2.5% day-1). Shrimp in all treatments grew significantly faster than those in the controls (2.0% day-1). The lower growth rate of shrimp fed fruit compost may have been due to dinoflagellates, which are known to negatively affect shrimp. Shrimp in tanks with chopped leaves of A. marina grew slightly better than shrimp in tanks with whole leaves. On page 3, just above ‘Data collection and calculation’’: ‘‘The post-larva shrimp were fed with commercial pellets at 5% of total body weight, estimated at the start and halfway the study. To encourage shrimp to use the natural feed produced in the tanks, …’’.

    Effect of three types of liquid compost combined with Avicennia marina leaves on growth and survival of tiger prawns (Penaeus monodon)
    Ariyati, Restiana Wisnu ; Rejeki, Sri ; Widowati, Lestari L. ; Elfitasari, Tita ; Bosma, Roel H. - \ 2019
    International Aquatic Research 11 (2019)4. - ISSN 2008-4935 - p. 311 - 321.
    Aquaculture - Fertilizer - LEISA - Mangrove - Shrimp

    The sustainability of prawn farming in brackish water ponds is controversial because of low yields and a history of mangrove clearing. Low yields are due largely to insufficient preparation of pond bottoms. Mangrove trees are often planted on pond bunds as window dressing. This study examines the effect of three types of liquid compost from vegetable, fruit, and both vegetable and fruit in tanks to which whole or chopped Avicennia marina leaves have been added to mimic local pond conditions. In a split-plot design, 28 square tanks were each stocked with one hundred 15-day-old post-larvae tiger prawns (Penaeus monodon). Four tanks were used as controls and 24 were assigned to the treatments, 12 with whole and 12 with chopped leaves. Of the treatment tanks, 4 received liquid compost from vegetable, 4 received fruit, and 4 received mixed vegetable and fruit. Shrimp were weighed at the start, halfway point, and the end of the 50-day trial, and fed at 5% of the estimated total weight; survival was counted at the end. The survival rates of treatments and controls (65–76%) were not significantly different. Shrimp in water with vegetable compost grew significantly faster (2.7% day−1) than in both treatments with fruit (2.5% day−1), while all treatments were associated with significantly faster growth than were the controls (2.0% day−1). The lower growth rate of shrimp fed fruit compost may have been due to dinoflagellates, which are known to negatively affect shrimp. Shrimp in tanks with chopped mangrove leaves grew slightly better than shrimp in tanks with whole mangrove leaves.

    The effects of decomposing mangrove leaf litter and its tannins on water quality and the growth and survival of tiger prawn (Penaeus monodon) post-larvae
    Rejeki, Sri ; Middeljans, Marcel ; Widowati, Lestari L. ; Ariyati, Restiana W. ; Elfitasari, Tita ; Bosma, Roel H. - \ 2019
    Biodiversitas 20 (2019)9. - ISSN 1412-033X - p. 2750 - 2757.
    Ammonia-N - Avicennia marina - Penaeus monodon - Rhizophora apiculata - Tannin

    Shrimp farming in Demak, Indonesia is often practiced in silvo-aquaculture systems in which mangrove trees are planted on pond bunds. As such, mangrove leaves and its substrates may have impact on penaeid shrimp production. In this area, mangrove re-growth proceeded with Avicennia marina while planting is mostly done with Rhizophora apiculata. We compared the effects of decomposing fresh leaves of A. marina and R. apiculata on water quality and on the performance of Penaeus monodon postlarvae (PL). A hundred of PL21 (postlarvae aged 21 days with weight of 0.28 g) were stocked in each of 30 aerated tanks containing 800 liters of brackish water (salinity of 21 ppt) for 37 days. Five treatments with three replicates for each mangrove species were assigned by adding into the tanks of 0.125, 0.25, and 0.5 g L-1 of air-dried leave, 0.125 of g L-1 minced leave and 0.125 g L-1 of leachate of minced leaves. The PLs were fed 3 times daily with pellets at 10 % of initial total body weight. Water quality parameters were recorded daily. Tannin, H2S and NH3-N concentrations were measured every ten days. Prawn’s body weight (BW) was measured and specific growth rate (SGR, % day-1) and survival rate (SR, %) were calculated after the end of experiment. Results were analyzed with ANOVA and Pearson’s correlation. The results showed that tannin in decomposing mangrove leaf litter up to a concentration of 0.5 mg g-1 did not have a significant effect on water quality and on the growth and survival of P. monodon PL. However, increasing leaf litter concentrations showed an increase in NH3-N concentration due to organic matter degradation. The accumulation of NH3-N may have caused the slow growth of shrimp PL in A. marina treatment. Shrimp PL in leaf litter leachates treatment has a higher growth rate than those PL in regular leaf litter in relation to nutritional value. Survival and growth varied from 62 ±14 to 70 ± 8% and 3.1±2.1 to 5.5±1.2% day-1, respectively. Although decomposing mangrove leaves of A. marina and R. apiculata had no toxic effects on P. monodon PL up to a concentration of 1.25 g L-1, but causing severe mortality for shrimp in tanks without water exchange. As a conclusion, the present of mangrove leaves in brackish water ponds with insufficient water exchange can be harmful to shrimps. However, if the water exchange is good, decomposed mangrove leaves can become organic fertilizer that beneficial for the growth of natural food for the shrimps.

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