Detailed Explanation of Key Technical Points for Soft-shelled Turtle-Rice Ecological Rotation

In recent years, China's soft-shelled turtle farming industry has developed rapidly. Adopting the soft-shelled turtle-rice rotation model can achieve rice cultivation without fertilization, while planting rice can also improve the bottom substrate of turtle ponds and reduce the occurrence of turtle diseases. Zhejiang Qingxi Soft-shelled Turtle Industry Co., Ltd. began conducting soft-shelled turtle-rice rotation experiments in 1999, and in practice summarized the ecological rotation model of "raising soft-shelled turtles for 2-3 years, planting one season of rice," which has been promoted and applied in production.

1. Construction of Rice-Planting Turtle Ponds

Each pond has an area of more than 3 mu, with the largest reaching 80 mu; the pond bottom soil is kept as the original rice field, only leveled without deep excavation; the perimeter of the turtle pond is built with cement bricks, with a wall height of 1.2 m, capable of maintaining a water level of 1 m; the inlet and drainage channels of the turtle pond are separately installed, with the inlet channel built on the brick-lined pond embankment, requiring the channel to be smooth on three sides; the drainage outlet uses a PVC elbow pipe to control the water level, capable of draining the pond completely, requiring convenient irrigation and drainage for the turtle pond.

2. Soft-shelled Turtle-Rice Rotation Model

Generally, after raising soft-shelled turtles for 2-3 years, one season of rice is planted. In mid-May, juvenile soft-shelled turtles are stocked, with a juvenile turtle size of about 180 g body weight, and a stocking density of 500 turtles/mu to 1000 turtles/mu, fed with soft-shelled turtle compound feed combined with fresh fish, and harvested before the end of July the following year. After catching the turtles, late rice is planted from late July to early August. During the rearing process, aside from using quicklime and other drugs for pond clearing and disinfection, chemical drugs such as antibiotics and chlorine preparations are not used, and Chinese herbal medicines such as Banlangen (Isatis root) are mostly used for disease prevention. Regarding rice cultivation techniques, because the turtle pond soil is fertile, short-stemmed, lodging-resistant, high-quality varieties should be selected, such as Yongyou No. 1, 98-110, etc. Secondly, in terms of cultivation techniques, the focus should be on "lodging prevention," adopting the "two controls and one prevention technique," namely: first, fertilizer control - no fertilization throughout the entire growth period; second, water control - the method is early field drying to control tillering, heavy field drying when 80% of the target panicle number of tillers is reached at the late tillering stage, so that rice roots grow deep; dry-wet alternating irrigation in the later stage to prevent lodging. Only pest control is performed without disease prevention, and the planted rice can reach the standard of pollution-free rice.

3. Several Observations

1. The soft-shelled turtle-rice rotation model is a relatively good ecological planting and breeding model. Raising soft-shelled turtles fertilizes the field, planting rice absorbs the fertilizer. Through animal-plant rotation, not only are pests and diseases reduced, but rice planted in the soft-shelled turtle-rice rotation area does not require mechanical plowing or fertilization, and only a small amount of pesticide is used for pest control, saving labor and reducing costs.

2. The soft-shelled turtle-rice rotation model, combined with fish-turtle polyculture, turtle-grass rotation, and other models, forms a relatively complete ecological planting and breeding system. According to the different harvesting seasons of soft-shelled turtles, rice, corn, perennial barley, etc. are selected for planting respectively. At the same time, @#@233@#@ can also be stocked in the turtle pond, and the planted perennial barley is fed to herbivorous fish, forming an ecological planting and breeding circulation system.

3. The soft-shelled turtle-rice rotation model has good ecological, economic, and social benefits. Raising soft-shelled turtles can increase the fertility of paddy fields, and planting rice can improve the bottom substrate of turtle ponds. After rotation, pests and diseases of soft-shelled turtles and rice are reduced, and the ecological benefits are very obvious. Raising soft-shelled turtles in rice fields improves the economic benefits of paddy fields. When planting rice in turtle ponds, no fertilizer is applied and little pesticide is used, reducing production costs, and rice yield increases by about 13%. The economic benefits of planting rice in turtle ponds are higher than those of paddy fields that only plant rice. Implementing soft-shelled turtle-rice rotation is conducive to stabilizing the area of grain fields, increasing soil fertility, and increasing the output rate per unit. It has good ecological, economic, and social benefits, and the soft-shelled turtle-rice rotation model is worth promoting and applying in production.