Biomonitoring of the Application of Monoculture and Integrated Multi-Trophic Aquaculture (IMTA) Using Macrobenthic Structures at Tembelas Island, Kepulauan Riau Province, Indonesia

Remark No.

Comments and Suggestions for Authors

Response to the reviewer’s comments

Remark 1

 Abstract should be rewritten: too many details about sampling and analyses and too little highlighting of concrete results, their validity and broader scientific relevance.

-       Eliminate too detail information on sampling procedure: “Sediment samples were sieved through 1 mm mesh.”

-       Add highlighted results: “The assemblage of macrobenthos at the IMTA site consisted of 9 species of gastropods, 3 species of bivalves, 5 species of polychaetes, and 2 species of crustaceans. While at the monoculture site 12 species of gastropods were observed; 4 species of bivalves, 8 species of polychaetes, 1 species of crustaceans, and 1 species of ophiuroid. At the reference sites, a relatively high abundance was observed with 27 species of gastropods, 11 species of bivalves, 3 species of polychaetes, and 1 species of crustacean. The good water conditions and possible absence of waste input from aquaculture, creating a more suitable habitat for macrobenthic life may be the cause for this.”

Introduction is almost completely void of any references. Are all presented facts and statements resulting from the authors’ own work and unpublished before? I doubt it.

Remark 2. 

Lines 43-47: Statistics from 2000 to 2013 is outdated and redundant. An up-to-date reference is required.

Updated some references on this issue:

“In 2018, global fish production is estimated to have reached about 179 million tonnes, of which 82 million tonnes, came from aquaculture production. Among major producing countries, China, India, Indonesia, Viet Nam, Bangladesh, Egypt, Norway and Chile, have consolidated their share in regional or world production to varying degree over the past two decades. The increase was mostly driven by marine capture fisheries, with production from marine areas increasing to 84.4 million tonnes in 2018 – up from 81.2 million in 2017. Unfortunately, the percentage of fish stocks that are within biologically sustainable levels have decreased from 90 percent in 1974 to 65.8 percent in 2017.”

Remark 3. 

Lines 48-49: “Eighty-five percent of the world's marine fisheries resources have been over-exploited, with some species having been forced into near extinction.” An up-to-date reference is required.

Up-to-date references have been added:

“Furthermore, current protein demand for the 7.3 billion inhabitants of the world is approximately 202 million tonnes globally; therefore , aquaculture needs to become more sustainable [1], [2]. “

Remark 4. 

Lines 50-51: “With the world’s human population expected to reach 9 billion by 2050, the demand for protein sources will continue to exceed the wild fishery production.” An up-to-date reference is required. Refer, e.g., to Henchion et al. (2017). Foods 6(7): 53.

Up-to-date references have been added:

“Furthermore, current protein demand for the 7.3 billion inhabitants of the world is approximately 202 million tonnes globally; therefore , aquaculture needs to become more sustainable [1], [2]. “ As seafood consumption tends to increase over the world [Henchion et al, 2017], aquaculture will be the prime source of fish because of the demands from consumers, and depletion of wild capture fisheries for the next a decade [1].

Remark 5. 

Lines 52-53: “Aquaculture is a solution to address the rising demand and declining availability, but the demand for seafood with a growing global population must be met with balanced and sustainable techniques for improved aquaculture production.” An up-to-date reference is required.

Up-to-date references have been added:

“Sustainability of the farming practice in order to maintain carrying capacity of water ecosystem become a main concern. Ref.[Henchion et al, 2017] emphasised serious concern on surrounding pollution and water quality, as it is over-dependent on a supply of fishmeal and fish oil, use of soy and chemicals in aquaculture feed, and habitat destruction.

Remark 6. 

Lines 56-58: “Various efforts have been made by the Indonesian government both central, regional, and in the private sector to increase the production capacity by extensification and intensification. The biggest challenge the aquaculture sector in Indonesia faces is balancing intensive but productive aquaculture practices with the carrying capacity of the local environments.” An up-to-date reference is required.

Up-to-date references have been added:

“Encouragement has been done by the government to the private sector to form fisheries associations. In line with this commitment, the government has established semi-government organizations where government staff and stakeholders are full members. The Tuna Committee, the Shrimp Committee and the Seaweed Committee has been formed since in 2004, headed by an independent chairman and has members representing both the government and the private sector [3].

Remark 7. 

Lines 58-59: “Sustainable aquaculture is a prospect that should always be taken into account when utilizing coastal resources.” An up-to-date reference is required. Refer, e.g., to Tagliapietra et al. (2020). water, 12: 894.

Some factors responsible for the decline of economic value of water ecosystems may include increasing use of aquatic resources,  and the mismanagement due to some conflicts of interest among users of water areas,  thus a suitable conceptual framework for environmental protection and sustainable development of the economies of water ecosystem are needed [Tagliapietra et al. (2020). water, 12: 894.],

Ref [ ] reported an environmental degradation caused by fish farming practice in Thailand over the last two decades, such as habitat destruction, water pollution, and ecological effects;

(Sampantamit et al, 2020)

Remark 8. 

Lines 66-70: “The accumulation of organic-rich sediments underneath farm facilities and the consequent depletion of oxygen in the sediment pore water may result in changes in infaunal assemblages. The depletion of oxygen is primarily a result of increased consumption by bacteria, and other organisms, of organic waste degradation. The subsequent waste may potentially result in qualitative and quantitative changes in the benthic environment.” An up-to-date reference is required.

It has been added up-to-date references as advised.

“Ref [   ] Ape et al (2019) reported organic matter accumulation on bottom sediments under fish farm at Mediterranean Sea.  Furthermore, recovery process of microbenthic community may depend on environmental conditions, whereas modifications of the benthic community structure persist over a longer time scale with an impact on benthic ecosystem functioning [  ] Lacoste et al ( 2019).”

Remark 9. 

Lines 71-73: “One such method is using the structure of macrobenthos, animals that are considerably sensitive to environmental disturbance, particularly that caused by organic enrichment.” An up-to-date reference is required.

It has been added up-to-date references as advised.

“As they are  exhibit a wide range of tolerance or sensitivity to different stressors [11], sedentary life in whole or part or their life in sedimentary habitat [10], and  have been widely used as an indicator for environmental assessments [12].  Marine soft-bottom macrozoobenthic communities have the inherent ability of integrating the environmental quality status reflecting the system condition adequately. They are relatively immobile residents [13].”

Results. While results, in general, are presented reasonably, few statements where references are necessary should be noted:

Remark 10

Lines 174-175: “However, they may also be found in sandy mud, clay, and rocky areas, and are able to live in high salinity water.” An up-to-date reference is required.

It has been added up-to-date references as advised.

 Mendes, C. L. T.  & A. Soares-Gomes. 2011. Macrobenthic community structure in a Brazilian chocked lagoon system under environmental stress. Zoologia, 28 (3): 365–378.]

Remark 11. 

Lines 178-179: The presence of Capitella sp. is related to its feeding type as sub-surface deposit feeders. They are considered opportunistic taxa.” An up-to-date reference is required.

It has been added up-to-date references as advised, as below:

“They are sub-suface deposit feeders and are considered an opportunistic taxa,  as they are well known to respond to changes in sediment organic content [5].  [14]Mendes, C. L. T.  & A. Soares-Gomes. 2011. It has been reported that high abundance of some opportunistic species and low biomass values were observed from a highly polluted phase to a transitional phase at coastal shallow soft-bottom environments. [15]  Samaniego, L.G.S. 2012.”

Remark 12. 

Lines 194-196 are redundant. The reader can see this trivial result from Table 2.

It has been re-written as advised, as below:

“The diversity index (H ') of the three study sites shows  slightly difference.  In particular, the lowest value was at the IMTA’s stations, implying the initial environmental disturbance when compared to the two other sampling locations. “

Discussion must be rewritten and highlight the new research avenues opened by the presented research results.

Remark 13. 

Lines 245-250 are redundant since the values of the evenness index show no statistically significant difference between the sampling sites of various types.

It has been re-written as advised, as below:

“Biological communities may be represented by species richness and species evenness. In particular, evenness expresses how evenly the individual species in the community are distributed over the different species [15  Heip et al, 1998], and how close in numbers each species in an environment is [16] Jost (2010). As a measure of biodiversity which quantifies how equal the community is numerically, the dominance of one or several species will decrease the diversity index value. In this study, assessment the dominance of a species over other taxa in the station is expressed by J’ Pielou evenness index. Although the values ​​of this index at the three study sites in the three sampling times showed slightly varied within the sampling sites, there were no significant difference. However, certain stations expressed higher values than others, this might be influenced by dominant taxa. As shown in Table 1, the dominant taxa at the three study sites were Nassarius sp , Anodontia sp (bivalves), and Nereis sp (polychaete). “

Conclusions are too trivial. They must be rewritten as well, based on the results from Fig. 3 and Fig. 4 that, at least visually, hint at some statistically significant findings. Conclusions must exhibit (and validate) the main findings of the study and how they relate to the state-of-art in the field and the study objectives.

It has been re-written correctly based on Fig.3 and Fig. 4, as below:

“By location, the use of NMDS ordination indicated grouping the sampling sites, clustering the IMTA, the monoculture, and the reference sites; whilst by time, there is no tendency of grouping stations, implying that the macrobenthic structure was not influenced significantly by seasonal variation of hydrography over the study period.”

Remark 14.

Lines 269-270 should be skipped or moved to Discussion, or even Introduction.

It has been re-written correctly as advised.

The English language needs further revision. Some typos are provided below, but there are many more:

Remark 15. 

Lines 20-21: “Sustainable aquaculture is a spirit that needs to be taken into account when it comes to the utilization of water resources.” What it means ‘a spirit’ in this context?

It has been re-written correctly as advised.

Remark 16. 

Line 24: “Samples of water and sediments samples.” The last word is redundant.

It has been re-written correctly as advised.

Remark 17

Lines 147: “is an organism can adjust both as a deposit feeder (in fauna settling under muddy sediments)”. A conjunction ‘that’, or ‘which’ is missing after ‘organism’.

It has been re-written correctly as advised.

Remark 18. 

Line 227: “this can be interpreted as the application of IMTA having suppress the potential” must be ‘suppressed’.

It has been re-written correctly as advised.