GB/T 35897-2018 in English

In-depth interpretation of the National Standard of the People's Republic of China GB/T 35897—2018 Technical Specification for Semi-Floating Raft Cultivation of Porphyra yezoensis

I. Background and significance of standard formulation

As an important aquatic resource, Porphyra yezoensis has a wide range of aquaculture bases and economic value in coastal areas of my country. However, traditional cultivation methods have problems such as low efficiency and waste of resources.

The formulation of GB/T 35897—2018 "Technical Specification for Semi-Floating Raft Cultivation of Porphyra yezoensis" aims to improve aquaculture efficiency, optimize resource utilization, and promote the sustainable development of aquaculture through scientific and standardized semi-floating raft cultivation technology.

II. Comparative analysis of standard frameworks

III. Interpretation of key technical requirements

1. Selection and optimization of cultivation facilities

Net curtain:The specifications are 90 strands (10×3×3), 99 strands (11×3×3), 108 strands (12×3×3), etc., and are made of polyethylene and polyvinyl alcohol formal fiber (vinylon) in a ratio of 4:6 or 5:5.

Raft frame:It is recommended to use bamboo with a diameter of 6cm~8cm and a length of 3.5m~4m. The height of the brackets at both ends is controlled at 80cm~120cm to enhance the ability to resist wind and waves.

2. Cultivation environment conditions

Bottom requirements: Sandy and muddy are preferred, with a flat beach surface to ensure smooth drainage and stable attachment base.

Water quality indicators: Meet the requirements of GB 3097 "Seawater Quality Standards", with a pH value fluctuating between 8.0 and 8.5.

3. Cultivation management optimization suggestions

Seedling cultivation stage: Put the shell spore seedling net (3 to 5 pieces in a group) into the sea and hang it on the cultivation raft frame, and cultivate it until the seedling length is 0.5cm~1cm.

Daily management focus: Strengthen inspection and maintenance, promptly repair damaged net curtains, raft frames and other facilities, regularly remove epiphytic algae, and ensure the cleanliness and light transmittance of the cultivation environment.

Fourth, harvesting technical points

• Algae length: Mechanical harvesting can be carried out when it reaches more than 15cm.
• Retained length: After harvesting, the length of the algae should be retained at 5cm~8cm to ensure the health of subsequent growth.
• Harvesting frequency: It is recommended to harvest once every 15 days~25 days. In case of strong winds, it should be harvested in time to prevent losses.

Five, implementation suggestions