Engineering Design and Operational Characteristics of Brackishwater Shrimp Farms in Relation to Soil, Water and Tidal Conditions
Mayur Tandel
Department of Fisheries Engineering and Technology, College of Fisheries, Mangalore, KVAFSU, Bidar, India.
R. K. Sadawarte
Department of Fisheries Engineering and Technology, College of Fisheries, Ratnagiri, Dr. B.S.K.K.V., Dapoli, Maharashtra, India.
A. N. Nikhil
Department of Fisheries Engineering and Technology, College of Fisheries, Mangalore, KVAFSU, Bidar, India.
Shubham Janbandhu
Department of Fisheries Resource Management, College of Fisheries, Mangalore, KVAFSU, Bidar, India.
Bhavika Tandel *
Department of Fisheries Resource Management, College of Fisheries, Navsari, KU, Gandhinagar, India.
Mitul Tandel
Florida Institute of Technology, Melbourne, Florida, United States.
Bhautik D. Savaliya
Department of Aquatic Environment Management, College of Fisheries Science, Rajpur, KU, Gujarat, India.
Meena Charandas Tembhurne *
Assistant Fisheries Development Officer, Edvan, Dist. Palghar, Maharashtra, India.
*Author to whom correspondence should be addressed.
Abstract
Aim: The present study assessed the engineering characteristics of operational brackishwater farms in Surat district, with emphasis on farm layout, pond and dike geometry, water supply, pumping and aeration systems, pond-bottom soil, source-water quality and tidal effects.
Place and Duration of Study: College of Fisheries Science, Navsari Agricultural University, Navsari, Gujarat. All water samples from brackishwater sources were collected from September to February (2020–2021).
Methodology: Brackishwater aquaculture along the Gujarat coast is closely influenced by farm design, site conditions, water-supply arrangements, soil characteristics and tidal dynamics. Fifty-four farms were randomly selected from six research sites: OS1, OS2, OS3 and OS4 in Olpad taluka and CS1 and CS2 in Choryasi taluka. Farms were grouped as small (<2 ha), medium (2–5 ha) and large (>5 ha), and classified according to water-supply mode as pump-fed or tide-cum-pump-fed. Source-water samples were collected near the sampled farms from the water sources used for culture.
Results: The sample comprised 46 pump-fed and eight tide-cum-pump-fed farms, with medium farms representing the largest group. Farm areas ranged from 2 to 50 ha, while individual pond areas ranged from 0.02 to 2.00 ha. Significant site-wise differences were observed for several pond and partitional-dike parameters, whereas peripheral-dike dimensions were comparatively consistent among medium and large pump-fed farms. Pond-bottom soils were predominantly clay loam, sandy clay loam and sandy clay, with soil pH ranging from 7.6 to 9.38 and electrical conductivity from 3.26 to 24.07 dS m−1 in pump-fed farms. Source-water temperature, pH, salinity, transparency and total suspended solids ranged from 27–32 °C, 7.6–8.3, 16–18 ppt, 22–28 cm and 76–118 mg L−1, respectively. The highest observed high tide was approximately 6.5 m. Although peripheral-dike erosion was observed across farm categories, within-category statistical tests did not show significant differences between tide-affected and unaffected measurements.
Conclusion: Overall, the findings indicate that brackishwater farm planning in Surat should integrate pond geometry, dike protection, water conveyance, aerator placement, soil characteristics and tidal exposure rather than treating these components independently.
Keywords: Brackishwater aquaculture, shrimp farm engineering, pond design, soil characteristics, tidal amplitude, dike erosion