Year-round and rotational freshwater prawn, Macrobrachium rosenbergii and paddy farming: soil quality, production and economics

A study was carried out at five upazillas (Dumuria, Fakirhat, Pirojpur sadar, Gopalgonj sadar and Kalia) of five southern districts of Khulna, Bagerhat, Pirojpur, Gopalgonj and Narail to understand the comparative production performance and any effect on soil quality in case of year-round golda (Macrobrachium rosenbergii), alternate prawn-paddy and year-round paddy farming. A direct interview of 55 farmers was taken, using pretested questionnaire, and soil samples were taken from selected farms before and after each crop. Among the five upazillas, farmers in Gopalgonj sadar and Kalia are not practicing year-round golda. Rotational golda-paddy farming has been recorded to result in maximum profit, with the highest of Tk. 310,912/ha/year in 2003 at Dumuria. Only paddy farming is less profitable than other two cropping patterns, irrespective of study sites. The nutrient status of soil in rotational golda and paddy farming has been found improved, compared to that of only golda or paddy farming.

Environmental assessment of shrimp farming in relation to livelihoods in the south-west coastal Bangladesh

The study was designed to assess the environmental impact of shrimp farming and implications on local livelihoods at the south-west coastal area of Bangladesh. All the stakeholders reported that shrimp farming negatively affected on the environment at the coastal area. The soil and water, fish habitation, agricultural cropland, grazing land, indigenous fish, household vegetations, trees and plants, land fertility and mangroves are affected negatively by the shrimp farming in the coastal area. About 44% of stakeholders agreed that mangroves were destroyed by the extension of shrimp farming in the study area. In the case of positive impact of shrimp farming on environment about 16% of stakeholders agreed that the household vegetations increased due to alternate rice and shrimp-prawn farming.

Farming seaweeds at SEAFDEC/AQD

The article presents the practices that have been developed or documented by SEAFDEC Aquaculture Department for farming seaweeds. These practices are: the cage culture of Kappaphycus, and the ‘rice planting’ method for cultivating Gracilaria. The seaweed gathering practices in coastal communities in western Visayas is also presented.

Oyster and mussel farming

The article discusses the oyster and mussel culture practices in western Visayas, Philippines. Spat collection, culture methods and management, and harvesting technique are discussed. The article also discusses mussel culture in New Zealand.

Offshore fish farming

The article discusses offshore fish farming, which is commonly practiced in some countries in Asia, North and South America, and Europe. Environmental factors such as the exposure of the cage to wind and waves, and its management are also discussed.

Farming the seaweed Kappaphycus

Seaweed farming is the top foreign exchange earner for the Philippines. Kappaphycus constitutes 80% of the Philippine seaweed export. It is sold in both fresh and dried forms; although dried seaweed has a greater demand, fresh seaweed is highly prices in restaurants. The 3 main seaweed products marketed are agar, alginate and carrageenan. A brief outline is given of farming operations and investment costs and returns.

Seawater irrigation systems for intensive marine shrimp farming in Thailand

The aim of the seawater irrigation system (SIS) is to clean up shrimp pond effluent and provide high quality seawater for shrimp farming. The system has 3 components: water intake; treatment reservoir and discharge system. There are criteria for site selection because shrimp farmers are required to form associations so they can work closely together. The construction site must be on the coastal area outside a mangrove forest and located away from a production agricultural area. All construction sites must have undergone an environmental impact assessment, and should be located on the area listed in Thailand's Coastal Zone Management Plan. Five SIS projects, which cover a culture area of 6,500 ha with 1,300 farmers (families), were completed and operated. The Department of Fisheries has planned for another 28 projects, that will cover almost 44,000 ha of culture area.