What is the reason for the floating of bitter grass water leek in the ecological breeding of pond

Water quality and aquatic weeds are important factors in the water environment, good water quality can promote the growth of aquatic weeds, and better aquatic weeds have the effect of purifying water quality, which can be adjusted by adding (changing) water and applying biological agents to control the growth of aquatic weeds.

1) Add or change water at the right time. According to the water level in the crab pond, add new water in a timely manner, generally the number of water added each time is about 5cm, when adding water, it should be added slowly, not too much water at a time. When changing the water, it should be injected while draining, so that the pool water is in the form of a slight flowing water.

2) Divert water regularly. Combined with weather changes, use biological agents and substrate improvers regularly on sunny days to adjust water quality and improve substrate, generally use once in the first half of May, and use once every 7 days from June to August, so that the transparency of the water body is kept at about 30cm.

The planting of aquatic weeds is not the more the better, but to control the appropriate coverage area, generally up to about 60% is appropriate, too many aquatic weeds will cause: pond bottom aquatic weeds rot, bottom dissolved oxygen insufficiency, large amount of bait waste, river crab black bottom plate, river crab activity difficulties and other drawbacks. If too many aquatic weeds are not treated in time, they are very perishable in the high temperature period and the later stage of breeding, causing huge losses to the breeding of black water, red water, river crabs, etc.

The depth of the water level directly affects the growth of aquatic weeds, which can be gradually deepened according to the growth needs of river crabs at each stage, and the aquatic weeds are not exposed to the water surface to ensure that the water level reaches "shallow spring, full summer, and moderate autumn". Generally, from February to March, the water level is controlled at 20-30cm to facilitate the planting of aquatic plants; From April to May, the water level was controlled at 40-50cm to give full play to the photosynthesis of aquatic plants. June to August is the highest temperature season of the year, and it is also the peak season for river crabs, and the water level is controlled at 60-90cm; After September, the water level takes its course. <>

As an important part of the ecological breeding technology of river crabs, the management and protection of aquatic weeds plays a decisive role in affecting the yield and quality of river crabs, especially before the arrival of the high temperature season, scientific aquatic weed management and protection technology can solve the problem of "crazy growth" of aquatic weeds, and effectively prevent the "bad water" phenomenon caused by the floating and decay of aquatic weeds. In the daily technical promotion work, the author summarizes the key points and precautions of composite aquatic weed management and protection technology, which are mainly based on Elophylla, Yellow Silk Grass, Black Algae rotifolia, Bitter grass, etc., which are introduced as follows

1. Maintenance. As the saying goes: "The size of a crab, look at the aquatic plants".

The growth of aquatic weeds determines the quality of water quality, and it is also a key factor in determining the yield of river crab farming. Therefore, it is particularly important to strengthen the management of aquatic weeds in the later stage of crab ponds, mainly to control the growth of aquatic weeds in the early stage by the water level, and to inhibit the growth of aquatic weeds by stubble cutting in the later stage.

2. Precautions. Remove the floating aquatic weeds in time. When the coverage rate of aquatic weeds is more than 50%, the aquatic weeds that surface during the day and sink to the water at night should be removed in time if they are found to be no longer floating after sinking underwater; If there are no new roots or the new roots are black, they should be removed in time.

Don't add too much water at a time. Generally, add 3-5cm of water, if the aquatic weeds grow too fast, the pool water should be deepened in advance, and the grass head should be kept below 30 cm of the water surface to inhibit its growth. Timing the mowing.

The amount of mowing each time can not be too much, it can be cross-cut at different points, and the amount of mowing is best controlled below 1 3; In case of hot and humid weather, the air pressure is too low, do not mow the grass for the time being, and then mow after the weather and air pressure conditions improve; After mowing, the substrate should be improved to prevent the water from being stirred when the aquatic weeds are cut, causing root rot and corrupting the water quality, causing hypoxia in the water body.