Brackish Water Aquaculture Research Articles

The Effect of Salinity Stress on Enzyme Activities, Histology, and Transcriptome of Silver Carp (Hypophthalmichthys molitrix).

A 56-day study was performed to examine the effect of freshwater (FW) and brackish water (BW 6‱ salinity) on the antioxidant ability, Na+/K+-ATPase (NKA) activities, histology, and transcriptome of the gill and kidney tissue in juvenile silver carp (Hypophthalmichthys molitrix). The results show that when juvenile silver carp were exposed to 6‱ salinity, the activities of superoxide dismutase (SOD) and catalase (CAT) were shown to be substantially increased (p < 0.05), while glutathione peroxidase (GSH-PX) activities in gill were not significantly affected (p < 0.05). In kidney tissue, SOD, CAT, and GSH-PX, enzyme activities peaked at 24, 8, and 4 h, respectively, but were not significantly different compared with the control group (p < 0.05). In addition, significant effects of salinity were observed for the NKA level in both the gills and kidney tissues (p < 0.05). The gill filaments of juvenile silver carp under the BW group all underwent adverse changes within 72 h, such as cracks and ruptures in the main part of the gill filaments, bending of the gill lamellae and enlargement of the gaps, and an increase in the number of mucus and chloride-secreting cells. Transcriptome sequencing showed 171 and 261 genes in the gill and kidney tissues of juvenile silver carp compared to the BW group, respectively. Based on their gene ontology annotations, transcripts were sorted into four functional gene groups, each of which may play a role in salt tolerance. Systems involved in these processes include metabolism, signal transduction, immunoinflammatory response, and ion transport. The above findings indicate that the regulation processes in juvenile silver carp under brackish water conditions are complex and multifaceted. These processes and mechanisms shed light on the regulatory mechanism of silver carp osmolarity and provide a theoretical foundation for future research into silver carp growth in brackish water aquaculture area.

Analysis of Development of Shrimp Aquaculture In Secanggang District, Langkat Regency, Sumatera Utara Province

The marine and fisheries sector's development is a part of the national development of Indonesia. Therefore, it is essential to ensure the industries' sustainability. Aquaculture is an industry that has a tremendous opportunity. Currently, Indonesia's aquaculture prospects are rising. Langkat Regency is a region in Sumatera Utara Province located in the East Coastal Region with good prospects for brackish water aquaculture. There are four goals in this study. This study aimed to analyze the distribution of shrimp aqua farm locations in the Secanggang District, investigate the type of shrimp aquaculture in the district, analyze the economic aspects of shrimp aquaculture in Secanggang District and study the optimal aquaculture strategy as a priority for developing coastal areas in Secanggang District. This study uses a quantitative approach to conduct a descriptive study. The study shows that the aqua farms in Secanggang District are located in the production area, converted forest area, wildlife nature reserve, and production forest. There are four types of Shrimp aquaculture in Secanggang District: intensive, semi-intensive, traditional, and natural/organic. The study also shows the economic analysis on costs, income, and the efficiency of R/C ratios per cycle on four types of aquaculture. This study also shows that shrimp aquaculture using the intensive system technique is the most appropriate and priority for shrimp aqua farming development in Secanggang District

KAJIAN TEKNIS PEMBESARAN UDANG VANAME (Litopenaeus vannamei) SECARA INTENSIF DI TAMBAK UDANG BPBAP SITUBONDO

The purpose of this study was to determine the intensive technique of rearing vannamei shrimp in shrimp hatchery installation Gelung, Brackish Water Aquaculture Center Situbondo, East Java. The data collection method used in this activity is a descriptive method that is the method carried out by looking at existing activites in the field with existing libraries. Activites undertaken include; pond preparation namely cleaning and washing of cultivation facilities, drying, HDPE plastic repair, map sterilization, installation of cultivation facilities and calcification of maps, preparation of aquaculture media including water filling and sterilization, fertilizer and POC application; selection and stocking of fry; feed management includes the type of feed, amount or dose of feed, frequency and technique of feeding, and check anco; water quality management includes observing water quality parameters, water change, water treatment and siphon; sampling; pest and disease control; harvest; and business analysis.

Maintaining Carbon Storage Does Not Reduce Fish Production from Mangrove-Fish Pond System: A Case Study in Coastal Area of Subang District, West Java, Indonesia

Deforestation and degradation of mangrove forests can be categorized as key environmental problems in Indonesia. These problems are majorly driven by overexploitation and the conversion of mangroves into brackish water aquaculture areas. One of the most common aquaculture systems traditionally developed in the coastal areas is the mangrove-fish pond system that combines fish production with existing trees. This study aims to analyze the environmental and economic aspects of mangrove-fish pond aquaculture in different levels of mangrove cover in the coastal area of Subang District, West Java, Indonesia. The spatial analysis method was used to analyze mangrove distribution and identify the current coverage in the aquaculture area. The economic aspect was analyzed, based on the costs and revenue from fish production, while the environmental aspect was represented by carbon storage, which is among the crucial mangrove ecosystem services. This study estimated carbon storage in the four-carbon pools: above- and below-ground biomass, deadwood, and litterfall. Based on the combination of visual interpretation of Sentinel 2A satellite images and field observations, approximately 667 ha of mangrove-fish pond was identified. This study found that there were no significant differences in fish production and net income from mangrove-fish pond aquaculture at various levels of mangrove cover. Meanwhile, the ponds with high mangrove cover stored higher carbon than those with medium and low mangrove covers. This indicates that maintaining carbon storage does not reduce fish production from mangrove-fish pond aquaculture.

Foresighting future climate change impacts on fisheries and aquaculture in vietnam

The Vietnamese fisheries sector, including both marine fisheries and aquaculture, has made spectacular progress in recent years, becoming one of the top seafood producing and exporting countries in the world. Looking forward, development goals of this sector must address challenges associated with climate change, including changing distribution of commercially important marine species such as tuna and disruptions to land-based aquaculture production systems. This study investigates the prospective climate change impacts on Vietnam's fisheries sector, focusing on four key commodities including capture fisheries (tuna), freshwater aquaculture (pangasius catfish and tilapia), and brackish water aquaculture (shrimp). The extent of impact varies, but climate change represents a potentially significant threat to sustainable production in each production system. Producers, policy makers, and other stakeholders need to plan for and adapt to climate change to ensure the sustainable development of Vietnam's fisheries sector.

Understanding the factors contributing to groundwater salinity in the coastal region of Andhra Pradesh, India

The present study focused on understanding the factors responsible for groundwater salinity in the coastal region, Prakasam district, Andhra Pradesh, India. Groundwater samples were collected and analysed for pH, EC, TDS, TA, TH, CH, NCH, EA, Ca2+, Mg2+, Na+, K+, HCO3−, Cl−, SO42−, NO3−, and F−. Groundwater quality was assessed using entropy weighted water quality index (EWQI), Chadha and Gibbs diagrams, ionic ratios, chloro-alkaline indices (CA), saturation indices (SI), principal component analysis (PCA), and hierarchical cluster analysis (HCA). TDS vs TH indicated that 86% of groundwater samples fall under brackish-cum-very hard water-quality type, while TA and TH relationship showed that 70% and 30% of groundwater samples fall under non‑carbonate hardness (NCH) and excess alkalinity (EA), respectively. EWQI classified groundwater samples into medium (22%), poor (40%), and exremely poor (38%) water quality types, indicating that most samples are not suitable for drinking purposes. Hydrogeochemical types in Chadha diagram showed saline water (Na+-Cl−) type in 92% of groundwater samples. Ionic ratios indicated that anthropogenic activities resulting from the leaching of surface water pollutants are the main source of groundwater pollution. Base ion exchange was indicated as the main process in CA indices. SI revealed precipitation of the calcite phase and dissolution of the gypsum and halite phases in groundwater. Evaporation appeared in Gibb's diagram as a primary process rather than a geogenic origin. PC1 (Na+, Cl−, SO42−, Mg2+, K+, and NO3−) and PC2 (HCO3− and F−) were considered salinity-process and alkalinity-process, respectively. The main sources of salinity in groundwater are brackish-water aquaculture and salt-making activities with household waste, septic tank spills, irrigation-return-flows, and chemical fertilizers being secondary sources. HCA classified groundwater samples into Group-I (46%), which represents domestic water, agricultural activities, etc., Group-II (30.24%), which shows the influence of both Group-I and Group-II, and Group-III (23.76%), which specifies brackish-water aquaculture and salt-making activities. Consequently, the present study obviously indicated that the groundwater quality of anthropogenic origin has largely overcome the influence of geogenic sources. The EWQI classification spatially delineated the study region into medium, high, and very high vulnerable zones, covering 28.69%, 32.75%, and 38.56%, respectively. Therefore, it is suggested to control the dumping of domestic waste and septic tank leaks, limit irrigation-return-flows and chemical fertilizers, ban brackish water aquaculture and salt production activities, and strictly implement an aquifer recharge management strategy to ensure human health. This study will assist decision-makers in addressing groundwater salinity issues in coastal regions.

An evaluation of the engineering suitability of extensive brackishwater ponds in Barru, South Sulawesi Province, Indonesia

In brackishwater aquaculture, pond engineering is essential to meet the cultured species' bio-physical requirements and potentially minimizing social and environmental impacts. This study evaluated the suitability of pond engineering designs and pond, dyke, and canal construction at family-run, extensive brackishwater aquaculture farms in Barru regency of South Sulawesi, Indonesia. Soil properties, topography, hydrological data, field surveys, and high resolution (0.6 m) Quickbird imagery were used to assess the suitability of local pond engineering designs and the efficiency of canals. The study shows that in 752 of the evaluated pond units (430 ha), about 70% of pond beds were not constructed at the optimal pond elevation. Basic engineering requirements for pond layout and dyke and canal designs were not addressed in more than 70% of the pond units. Cease-to-flow conditions commonly occur due to the sedimentation of canals. Flows are also attenuated due to collapsed dykes. Farmers disregarded soil limitations and the impacts of tidal conditions and wave regimes. It is unlikely that shrimp and fish production in the region can increase without significant improvements in pond engineering. The problems identified by the study are not unique to Barru; they also occur in other extensive aquaculture areas in Indonesia and the region. Increased awareness of the need for improved pond engineering techniques is urgently needed to safeguard the economic and environmental sustainability of Indonesia's valuable aquaculture industry.

Technical efficiency analysis of shrimp farms in Andhra Pradesh, India using stochastic frontier approach

Brackishwater aquaculture sector is dominated by the exotic vannamei shrimp farming, which is the economic engine of Indian aquaculture. In 2019-20, exports of 12,89,651 t of Indian marine products fetched foreign exchange worth ₹46,662.85 crores and farmed shrimps accounted for about two-thirds of the shrimps exported. Shrimp farming is export oriented and market price often fluctuates widely impacting the profitability significantly. We conducted this study to estimate technical efficiency of the shrimp farmers In Nellore District, Andhra Pradesh State which tops in shrimp aquaculture in the country. The data were collected through structured questionnaire using personal interview from 80 farmers during COVID 2020 pandemic period. The farm specific technical efficiency varied from 75 to 94% with a mean of 93%. The estimates of the discrepancy parameter γ indicated that 93% of the difference between the maximum possible output and actual output were due to differences in technical inefficiencies of farmers Feed and labour are the significant variables compared to other variables. The results indicated that farmers need to be encouraged to apply more feed to increase shrimp production. Keywords: Stochastic production frontier, Sustainability, Technical efficiency, Vannamei shrimp aquaculture

Greenwater Technology for Controlling Vibriosis and Achieving Higher Shrimp Production - A Case Study

Disease due to luminous Vibrio has been a major problem in the shrimp industry. Brackishwater shrimp Penaeus monodon is susceptible to fatal effects of luminous vibriosis adversely affecting the shrimp production and creating economic losses in India. Different technologies have been introduced to control the disease. One of the techniques reported to work against luminous bacteria is greenwater culture system (or finfish–shrimp integrated culture system). The greenwater culture system has been proven the most functional and innovative technique, wherein euryhaline finfish are propagated as bioremediators in an isolated net pens/cages inside the shrimp growing ponds or shrimp are cultured in fish produced greenwater. This paper reports a case study on the successful demonstration of greenwater technology based on the integration of milkfish, Chanos chanos and grey mullet, Mugil cephalus in pens for environmental and health management of brackishwater aquaculture with the result of higher production of shrimp, Penaeus monodon. The greenwater technology has been found to be effective as biomanipulators in controlling the luminous bacteria disease and can be a good alternative to expensive microbial products/probiotics in the aqua-farming ponds throughout the culture period.

Protein content of Spirulina sp. Cultured Using a Combination of Urea and TSP Fertilizers

This study aims to determine the effect of the combined use of Urea and TSP fertilizers on the Protein content of Spirulina sp. This research was conducted for 10 days at the Center for Brackish Water Aquaculture (BPBAP) Takalar. The method used in this study is an experimental design with Completely Randomized Design (CRD) using 4 treatments with 3 replications, namely Treatment A (0.4 g/l Urea + 0.008 g/l TSP), B (0.5 g/l Urea + 0.010 g/l TSP), C (0.6 g/l Urea + 0.012 g/l TSP) and D (0.4 g/l Urea + 0.008 g/l TSP). The data obtained were analyzed using descriptive analysis method. The results showed that the use of a combination of Urea and TSP fertilizers could have an effect on the protein content of Spirulina sp. with the highest protein content obtained in treatment C of 34.33%.

A Comparative Study between Managed Aquifer Recharge and Other Community Water Supply Options in Coastal Bangladesh

The acute scarcity of safe water exists in disaster-prone coastal Bangladesh due to the occurrences of brackish or saline and arsenic contaminated groundwater, the salinization of freshwater ponds by inundation during storm surges, and brackish water aquaculture. Millions of people living there mainly depend on pond water and rainwater harvesting system and face severe difficulties to collect freshwater, particularly during the dry season. Therefore, various community water supply technologies, e.g., RO, SIDKO, RPWS, SkyHydrants etc. have been established to meet their daily needs, though the majority of these technologies fall short of the value of time and effort of water collection and sometimes fail to supply water of desired quality. Managed Aquifer Recharge (MAR) technique, also a community water supply system, was designed to provide safe water by creating underground storage of freshwater where ambient groundwater salinity is reduced by infiltrating rooftop or pond water through wells. Understanding the need to sort out the best water supply option, a comparative study has been conducted between MAR and other water supply technologies, and among all of them the MAR has been demonstrated as a low cost, reliable, sustainable, and durable option for providing safe drinking water to the community round the year. The Dhaka University Journal of Earth and Environmental Sciences, Centennial Special Volume June 2022: 157-166

Abundance of Phytoplankton in Vannamei Shrimp (Litopenaeus vannamei) Farming Pond at the Center for Brackish Water Aquaculture Fisheries (BBPBAP) Jepara

Vannamei shrimp (Litopenaeus vannamei) is one of the commodities that is a priority in aquaculture development activities in Indonesia. The success of vannamei shrimp culture is influenced by various factors such as fry quality, feed quality, land carrying capacity, application of biosecurity and good water quality management. Water quality is closely related to the phytoplankton community contained in a waters. This study aims to analyze the abundance and dominance of plankton species found in pond waters. Monitoring the abundance of phytoplankton was carried out in 4 plots of vannamei shrimp aquaculture ponds at the Brackish Water Aquaculture Fisheries Center (BBPBAP) Jepara, namely plots A51, A51, A61 and A62. Identification and calculation of phytoplankton cells were carried out using a haemocytometer and Sedgwick. The results of the analysis showed that the highest abundance of phytoplankton was found in plots A61 at week 9 with a cell number of 36.73 x 106 cells/L, while plots A51, A52 and A62 decreased. Overall plot A62 had better water quality conditions when compared to plots A51, A52 and A61 indicated by the phytoplankton abundance value of 34.63 x 106 cells/L at week 9 and the dominance index of green algae, namely D > 0.5.

MINAWISATA PERIKANAN AIR PAYAU DI DESA SUNGAI CUKA TANAH LAUT

The brackish water aquaculture area in Sungai Cuka Village used to be the location of a pond that produced a lot of brackish water fish such as Milkfish (Chanos chanos), Windu Shrimp (Penaeus monodon), Mullet (Mugil cephalus), Mangrove Crab (Scylla serrata), White Snapper ( Lates calcarifer), and others. Coal mining has begun to be opened upstream of the estuary so that coal waste is carried downstream and pollutes the pond water which causes the ponds to die. This has an impact on the income of the fishermen who began to decline, finally they decided to leave the pond to look for other livelihoods. So the problem raised is how to design a brackish water aquaculture educational recreation area with a regional locality approach? This writing aims to restore aquaculture activities in Sungai Cuka Tanah Laut Village as an effort to revive dead aquaculture areas and settlements supported by pond water conditions that are free from coal waste pollution. The step to achieve the goal is to design a brackish water fishery tourism area based on educational recreation tourism. The method applied is a contextual architectural approach which is expected to maintain the characteristics of the coastal area, can renew the image of the aquaculture area which is slowly disappearing, and become a recreational tourism and fisheries education area.

Mapping the spatial distribution of global mariculture production

Mariculture (marine and brackish water aquaculture) has grown rapidly over the past 20 years, yet publicly-available information on the location of mariculture production is sparse. Identifying where mariculture production occurs remains a major challenge for understanding its environmental impacts and the sustainability of individual farms and the sector as a whole. We compiled known mariculture locations and applied a simple production-allocation approach to map remaining global mariculture locations across 73 countries using the key determinants of distance to shore and ports, and average productivity (tonnage) of known farms. Our map represents 96% of reported fish and invertebrate mariculture production for 2017, but excludes algae which constitutes half of global mariculture production. We provide, for the first time, a publicly available spatial database of known and estimated mariculture locations. We discuss the utility and limitations of the existing data and our modeling approach, and highlight the key data gaps and future challenges for mapping aquaculture. Our results provide a vital resource for mariculture and environmental researchers, but we emphasize the need for a standardized, ground-truthed global spatial database of aquaculture locations and farm-level attributes (e.g., species, production type) to better understand the distribution of production and adequately plan for future growth.

Evaluation of Histopathological Changes in Cantang Groupers’ Brain and Gill Infected with Streptococcus Iniae

Cantang hybrid grouper is the result of hybridization between female Macan grouper (Epinephelus fuscoguttatus) and male Kertang grouper (Epinephelus lanceolatus). Hybrid fish have better performance in terms of growth, resistance to diseases, and tolerance to environmental factors, compared to the parents. One of the diseases that can attack fish is an infection induced by Streptococcus iniae (S. iniae), which is quite a dangerous bacterium since it can cause mass death of fish. The present study aimed to investigate the pathological changes of the brain and gill of Cantang hybrid grouper (Epinephelus fuscoguttatus and Epinephelus lanceolatus) infected with S. iniae. A total of 180 groupers from the Management Unit of Brackish Water Aquaculture, Situbondo, Indonesia, were included in the current study with a length of 7 cm. The experimental study was conducted using a complete randomized design, including three treatments and three repetitions for each one (n = 20). The main parameters to observe the histopathological changes in the fish internal organs, namely the gill and the brain at the beginning and the end of the study. Moreover, the supporting parameter was the water quality which included the temperature, oxygen content, pH, and salinity. Several observations including the pathogenicity test, Lethal Dosage 50 test, observation of clinical symptoms, and observation of histopathology were done during the treatment. The obtained results were indicative of the histopathology damages in the brain and gill tissues of the Cantag hybrid groupers infected with S. iniae. Different scores of lesions, infiltration, congestion, and degeneration were indicated in the brain tissue. Furthermore, the gill damages consisted of hyperemia, congestion, and infiltration. In conclusion, Cantang hybrid groupers (Epinephelus fuscoguttatus and Epinephelus lanceolatus) infected with S. iniae indicated the clinical symptoms, anatomical pathology, and histopathological changes.

Brackishwater Aquaculture Health Management with Special Referencve to Shrimp Farming in India: Status and the Way Forward

The brackishwater aquaculture in India has evolved significantly during the past four decades and has been dominated by shrimp farming. The native shrimp species have been replaced by the Pacific white shrimp. Since its introduction there has been tremendous growth in aquaculture production, contributing significantly to the economy. With the intensification and expansion of aquaculture, challenges due to disease and crop failures have become the most important concerns. The white spot disease (WSD) and Hepatopancreatic microsporidiosis or Enterocytozoon hepatopenaei (EHP) are the most important diseases causing significant economic loss to the Indian shrimp farming. Aquatic animal health management (AAHM) constitutes management practices primarily designed to prevent diseases. The AAHM at the Government level includes, import risk analysis (IRA), aquatic quarantine, disease surveillance and reporting, zoning, and contingency planning. Options at the field level on disease control and prevention are limited since these are still under research and development. The Indian brackishwater aquaculture sector has major Acts and other legal instruments in place for Coastal Aquaculture. The Indian brackishwater aquaculture has tremendous scope to increase aquatic productivity applying the principles of better management practices (BMPs) on environmental sustainability principles and make the sector economically efficient and a socially equitable enterprise, and have been adequately addressed in the recently launched Pradhan Mantri Mathsy Sampada Yojana (PMMSY).

Institutions and institutional changes: aquatic food production in Central Luzon, Philippines

Aquaculture is the most rapidly growing food production sector globally. In certain coastal social-ecological systems, this has resulted in significant changes and sustainability challenges. In particular, coastal environments which used to support only capture fisheries are becoming sites for brackish water aquaculture production; this impacts the sustainability of aquatic food production. Sustainability challenges associated with aquaculture expansion and intensification necessitate a contextually rooted understanding of institutions and institutional changes which can be used as an informed basis for leveraging institutions to achieve desirable sustainability outcomes in the aquatic food sector. This research used a qualitative empirical case study involving in-depth interviews, participant observation, and analysis of institutional documents in the region of Central Luzon, Philippines. It applied the inter-institutional systems concept which considers multiple institutions with distinct but linked purposes and functions in the societal spheres of state, market, and civil society. The study found that aquaculture emerged as an important livelihood because of rice farmers’ need to adapt to saltwater intrusion into what were formerly rice farms. It grew into an industry due to developments in the availability and accessibility of inputs such as fingerlings and feeds. This process was also driven by the high demand and high profitability of fish farming at the time. Regulatory institutions have not adequately adapted to protect the environment. Market institutions adapted but the changes mostly benefited consignacions (middlemen) and large-scale players. However, organised groups of collaborating smallholder fishers and fish farmers are helping to address the disadvantages they face.

Perspectives for improving circular economy in brackish shrimp aquaculture

Shrimp farming in South-East Asian and Latin American coastal regions generates economic benefits for the producer countries and contributes to a healthy nutrition of consumers. However, shrimp farming uses great amounts of fish meal and fish oil in the feed for the provision of essential proteins and polyunsaturated fatty acids during growth. This practice contributes to the environmental burden of the production process, as it is estimated that 25% of the total wild capture fish is used to produce these compounds. Also, intensive brackish water farming in coastal regions promotes the shrinkage of mangrove forests and the contamination of surrounding soil and water resources, causing further environmental degradation. In this work, several concepts for wastewater and sludge treatment in brackish water aquaculture are reviewed, and a novel concept that combines aquaculture with the production of macroalgae and microalgae is proposed to achieve a circular system. Macroalgae can assimilate nitrogen and phosphorus in the wastewater stream, which enables the recirculation of the salty water. Solid residues are converted via anaerobic digestion into several short-chain carboxylic acids and methane. While methane can be used for electric energy and heat provision, the acids can be consumed by heterotrophic microalgae. Both macroalgae and microalgae can be applied as feed additives in shrimp aquaculture, providing proteins and polyunsaturated fatty acid sources. This integrated concept can enable the production of shrimp without the addition of fish meal and oil, enhance nutrient recycling in brackish aquaculture, and minimize the contamination of coastal land and water.

Inland saline aquaculture increased carbon accumulation rate and stability in pond sediments under semi-arid climate

Similar to fresh- and brackish water aquaculture ponds, commercial shrimp farming in degraded saline areas holds the potential to bury carbon (C) in the sediments. However, studies on the mechanisms of sediment C dynamics and C-flux in response to inland saline aquaculture management practices are still scarce. Therefore, the objectives of the present study are to quantify the C burial rate in inland saline aquaculture ponds and assess the impact of inland saline aquaculture on sensitive C fractions in the bottom sediment of the ponds. The sediment samples (n = 12 from each pond) were collected from six shrimp farming ponds (1000 m2 area of each pond) of different ages. The sediment depth, sediment accumulation rate and the levels of total carbon (TC), total organic carbon (TOC) and sediment oxidizable organic carbon (SOC) and its different fractions were determined using standard procedures. The data were analysed by one-way analysis of variance (ANOVA), followed by the Duncan's multiple range test for comparing the means, and the Pearson correlation test was used to assess the relationship between the different pond sediment parameters and SOC content. The results revealed that the annual C accumulation rates varied from 902 to 1346 kg C ha−1 year−1 in 7-year-old earthen ponds (EPs) and bottom cemented ponds (BCPs), respectively. The sediment C fractions, including TC, TOC, SOC and its fractions (very labile, VLc; labile, Lc; less labile, LLc), and non-labile carbon (NLc)) were progressively increased over the pond age. The inland saline aquaculture practices over the years increased both active (AC) and passive carbon (PC) pools in the pond sediments, helped in the restoration and improvement of sediment quality and enhanced C sequestration potential of the sediments. Furthermore, a significant increase in the level of particulate organic carbon (POC) in BCPs justified that the non-ploughing practices at BCPs facilitated the formation of macro- and micro-aggregates, thereby increasing the C retention and stability of the pond sediments. This study suggested that the shrimp farming ponds in semi-arid saline soils represented considerable C burial hotspots, enhanced the stable passive C pools and improved the sediment quality.

Labor characteristic on brackish water aquaculture in Aceh Tamiang Regency

Farmer and labor have a working relationship in shrimp aquaculture. These relationships are affected by the social status, economic motive, and competence of the workers/laborers. This research aims to (1) analyze the characteristics of labor in Aceh Tamiang Regency and (2) analyze the work relationships existing in each technology used. The research was conducted in April – May 2021. Primary data were collected from interviews with the purposive respondents using a structured questionnaire. Meanwhile, literature reviews are secondary data obtained from literature reviews and information provided by related institutions. The research findings showed that 89% of the respondents use traditional technology, 5% semi-intensive methods, and 6% apply intensive technology. Conventional technology is commonly self-employed and involves family members. In contrast, the semi-intensive and intensive technologies employ skilled laborers with monthly salaries and the yield sharing system (bagi hasil). Consequently, the capacity of the traditional fish pond farmers needs to improve to achieve the skillful need. Employee relationships in semi-intensive and intensive brackish water business ponds are mainly hired skilled labor from other places by legal binding. Both neglected to employ local people to maintain a social relationship.