[0051] Example 1
[0052] A method of cultivating kelp and Asparagus in rotation. From November to June of the following year, kelp is cultivated, and from May to November, the specific method is as follows:
[0053] 1. Kelp culture:
[0054] 1. Seedling holding at sea
[0055] Before transporting kelp seedlings to the sea area of the farm, avoid exposure to the sun, and the best time to hang the seedlings is early in the morning.
[0056] Choose the coastal sea area of the inner bay with small wind and waves, smooth tide, fertile water quality, transparency of 1m to 3m, and less floating mud and algae for temporary cultivation of kelp seedlings. Cut the seedling curtain into 50cm~60cm seedling ropes, hang the upper end on the hanging rope, and tie the falling stone at the lower end to stabilize it under the water 80cm~120cm, and the interval between each seedling rope is about 20cm. During the temporary rearing of seedlings, ammonium nitrate is required to be fertilized by hanging bags. Hang a bag every three seedling ropes. When hanging the bag, each plastic bag contains 150g~250g fertilizer. Use a needle to pierce two holes with sand or small rocks inside and sink into the water. .
[0057] 2. Kelp split seedlings
[0058] Seedlings can be divided by 20±2cm. When dividing the seedlings, remove the fine seedlings from the seedling rope and clamp it on the seedling rope. The seedling rope is 250cm long, one seedling is clamped every 8cm, and 30-32 seedlings are clamped in each rope. The seedling breeding method adopts the double-rope flat breeding method. The seedling breeding density is 50cm apart, and the seedling quantity per mu is 12,000.
[0059] 3. Develop
[0060] The kelp is mainly raised in raft culture, and its high-yield characteristics can be exerted by the flat culture method. The floating raft is set parallel to the sea current, connecting the seedling ropes between two adjacent rows of floating rafts, so that the seedling ropes are hung flat in the sea water, so that the kelp receives uniform light, which is beneficial to the growth of the kelp. The adjustment method is to initially hang the water layer 80cm~120cm, and raise the water layer according to the change of transparency. When the water temperature rises above 12℃, the water layer should be properly raised to 30cm~40cm. Inverted every 30d after flat rearing. Generally, cutting is done at the end of March and early April. Generally, two-fifths to one-third of the total length of the kelp is cut off. The water temperature is 5℃~6℃.
[0061] From after seedling division to thick harvest before harvest, it is the stage of offshore grow-out management: this stage takes about six to seven months in the northern sea area.
[0062] The reasonable close planting and the density of kelp culture are mainly determined by the number of seedlings, seedling distance, rope distance, raft distance, etc. The specific breeding amount is: 25-30 seedlings per rope (net length 2m) in the first-class sea area, 10,000 to 12,000 seedlings per mu; 30-40 seedlings per rope in the second-class sea area, 1.2 seedlings per mu Ten thousand to 16,000; there are more than 40 rope-clamped seedlings in each of the three types of sea areas, and more than 16,000 seedlings per mu is more suitable.
[0063] The adjustment of the aquaculture water layer is actually to adjust the light received by the kelp. Using the same management method and stocking in different water layers, kelp growth has different results. This shows that the fast-growing water layer of kelp is suitable for light, while the slow-growing water layer is not suitable. In the process of kelp culture, the adjustment of light conditions is a more complicated problem. Because the condition of light in the seawater is related to the transparency and flow rate of the seawater, the light-receiving condition of the kelp is also related to the growing form and stocking density. Therefore, each sea area should determine the dimming method according to the characteristics of its own sea area and breeding methods.
[0064] (1) Early development
[0065] Kelp seedlings do not like strong light, so they can be hung deep in the first-class sea area after splitting. The initial water layer in the northern sea area is 80cm~120cm; the initial water layer in the southern general sea area is 60cm~80cm, and the mixed water area is 30cm~40cm. In the second and third category sea areas, close temporary breeding is adopted. That is, temporarily hang seedling ropes 1 to 2 times more on each row of rafts, or add a row of temporary rafts between two rows of rafts, and evacuate after the kelp grows to a certain size. The close suspension can not only prevent the early growth of kelp from being inhibited by strong light, but also make full use of the fertilizer area to concentrate fertilizer and reduce the loss of fertilizer, which is very beneficial to the early growth of kelp.
[0066] (2) Mid-term development
[0067] With the increase of kelp individuals, the phenomenon of shading and blocking each other becomes more and more serious. The growth of kelp in the deep water layer will gradually slow, so the water layer must be adjusted in time. The water layer in the northern sea area is generally controlled at 50cm~80cm. . At the early stage of growing, the seedling ropes that are kept tightly and temporarily raised, the time for evacuation at a certain time must be mastered, and it should not be too early or too late. Too early will lose the meaning of close holding, and too late will cause the algae to receive insufficient light and affect their growth. The more uniform standard for the suitable evacuation time is that when the length of kelp reaches about l20cm (that is, when the kelp is crisp and tender), evacuation must be carried out.
[0068] In sea areas with deep water and large currents, the seedlings can be hung horizontally to harvest. During the entire breeding process, just adjust the length of the sling and the flat rope, or adjust the growing water layer by adding or subtracting buoyancy according to the changes in the transparency of the seawater.
[0069] (3) Late development period
[0070] Light is an important factor that promotes the thickening of kelp and increases material accumulation. However, when the seawater temperature is not suitable for thickness growth, the light can only promote the local thickness of the kelp. It is often the kelp on the seedling rope with better light or the base is thicker, with thicker leaves and darker color. The lower kelp is poorly thick due to the shading of the upper kelp. When the seawater temperature rises to a suitable thickness for growth, not only the parts with good light will thicken faster, but the parts with weak light will also thicken accordingly. At this time, the materials produced by kelp photosynthesis are mainly supplied for the accumulation of materials, and rarely for long and wide growth. Therefore, while considering the use of light to promote thickness growth, the seawater temperature must be considered. When the seawater temperature reaches a suitable thickness growth, the light must be adjusted in time to promote its thickness growth. This not only overcomes the influence of the growth of the water layer prematurely, but also prevents the influence of the growth of the water layer too late. In the first-class sea areas in northern my country, when the water temperature rises above 8°C in spring, kelp enters a period of thick growth. In mid-to-late April, when the water temperature rises to 11~12°C, the water layer is raised to 30~40cm, and the mature kelp can be collected at the same time.
[0071] In order to promote the thick growth of kelp in all parts, the water layer should be raised in time and the light should be increased in the late stage of aquaculture. At the same time, the harvest should be carried out. The mature kelp should be collected in between, so as to improve the light receiving conditions and promote thick growth. In addition, cutting tips and other measures are effective methods to improve the light conditions of kelp in the later stage.
[0072] 4. Harvest
[0073] Fresh vegetable processing kelp is generally harvested in early and mid-May, when the fresh-dry ratio reaches 7-8:1, it can be harvested indirectly, and the water temperature can be above 15℃ and can be harvested by rope. Dried vegetable processing kelp is harvested when the water temperature in the sea area reaches 17℃ or higher, then the whole rope can be harvested.
[0074] 2. Asparagus cultivation
[0075] 1. Seed source and transportation
[0076] Gracilaria seedlings mainly come from southern coastal areas such as Fujian. In mid-to-early May each year, when the water temperature in the south is around 22°C, Asparagus is in an exponential growth period. Select Asparagus that grows vigorously, has purple color, less algae, and is clean and pollution-free. After selection, cleaning, and cooling , Sampling refrigerated and insulated truck (4~8℃) for transportation.
[0077] 2. Temporary Raising at Sea
[0078] At this time, the temperature in the northern sea area is about 13°C, which is below the suitable growth temperature of Asparagus. The seedlings of Asparagus cultivated in the north are transported to the sea area with smooth tide and relatively small wind and waves for temporary cultivation. The holding time is 3-4 weeks, when the temperature reaches 16℃, the seedlings will be clamped.
[0079] 3. Clip seedlings, hang seedlings
[0080] In mid-to-late May, as the sea water temperature rises, kelp is gradually harvested. When the temperature reaches 16°C, asparagus seedlings start to be clamped. Choose 180-360 silk polyethylene rope (3 strands 3 flowers) as the seedling rope. The length of the seedling rope is generally 5 meters, the twist of the seedling rope must be appropriate, too loose and easy to fall off, too tight to damage the seedling. The new seedling rope is soaked in water for 1 day, and the old seedling rope is disinfected and washed with 200ppm bleaching powder.
[0081] Use cluster clamp method to clamp seedlings. The amount of clamping seedlings is 200g per metre of seedling rope. The asparagus seedlings are cut into small clusters of about 20g through the seedling rope, and a cluster of seedlings is clamped every 8cm-10cm. It should be clamped in the middle of the seedling, with 10cm--12cm exposed at both ends. When clamping seedlings, prevent sun exposure and algae drying.
[0082] Hanging seedlings on the sea should avoid direct sunlight, and adopt the flat breeding method for breeding. Connect the two ends of the clamped seedling rope to the hanging rope on the floating ridge, and hang a falling stone at both ends of the seedling rope.
[0083] 4. Breeding management
[0084] (1) Water layer adjustment. The adjustment of the cultivation water layer actually regulates the light receiving of Asparagus. Asparagus is a kind of light seaweed, it grows slowly under too weak light, but too strong light can inhibit the growth, even the pigment is decomposed by the sun and fades and turns yellow. If it is not adjusted in time, it will turn white and fall off. Adjust the dragon according to the transparency. The transparency of the water layer, the culture water layer and the sea area is the same. From May to June, the transparency is greater than 200cm, and the water layer should be controlled below 150cm; in July, the transparency is between 150cm~200cm, and the water layer is 80cm~ The growth is better between 100cm; in August, the transparency is between 150cm~200cm, and the asparagus is hanging in the water layer between 70~90cm; in September, the transparency is between 200cm and 240cm, and the asparagus is hanging in the water layer. 100cm.
[0085] (2) Adjust the raft frame. In addition to appropriately increasing or reducing the buoyancy, the broken rope should be added in time; always pay attention to check the firmness of the raft frame, the tightness of each raft must be the same, and the uniformity must be uniform to ensure production safety. During the breeding process, the raft frame may be deformed due to the influence of the tide, wind and the growth of asparagus, adjust the buoyancy according to the weight of the asparagus, and keep the water layer of the asparagus hanging at 60cm~150cm; adjust the raft frame The direction is parallel to the direction of the tide or wind;.
[0086] 5. reward
[0087] After cultivating for 30-40 days, the wet weight of Asparagus vulgaris per meter reaches about 3-4kg and it can be harvested. The harvest should be landed with the seedling ropes, and the seedling ropes should be separated using corresponding machinery. Select part of the algae with thicker bodies and purple-black color as seedlings, and continue to separate seedlings and cultivate 3-4 crops throughout the growing season. The remaining asparagus is dried in the morning on a sunny day to ensure that the asparagus can be exposed in time without deterioration. If it is not dried on the first day, it must be dried on the next day for storage in bags.
