Studies Of The Effect Of Main Factors On Growth For Litopenaeus Vannamei In Greenhouse

Facilities greenhouse cultivation is the most widely use aquaculture model in breeding litopenaeus vannamei at the present in China, it solves the problem such as high rates of shrimp disease and acquires good yield and economic benefits, but there are still exist some problems such as outbreaking prawn diseases and yield instability in the process of cultivation, which seriously affect the aquaculture production and benefit. Investigate its reason, the greenhouse aquaculture model has not grasps the best technology in regulating multiple physical and chemical factors at home. Although there are some studies about water environment influencing the growth of the shrimp at this stage, but they were basically carried out in the laboratory or around the pond in the open air. Even under the condition of the facilities greenhouse cultivation, the studies about physical and chemical factors influence the growth and production of shrimps are only aim at one or few kinds of factors. The comprehensive study about a variety of physical and chemical factors influence growth, production under the condition of facilities greenhouse cultivation has not yet been reported.This study carried out in Daishan Nanfeng aquaculture testing ground in August 2014 to November 2014.By monitoring the main physical and chemical factors such as temperature, salinity, p H, DO, TAN, NO2--N, sulfide, chl.a in ten aquaculture ponds, analyzing the trend of each physical and chemical factor and using analytical methods such as factor analysis, correlation analysis, path analysis and so on study the relationship between daily amount of bait casting quantity and shrimp body length and the main physical and chemical factors, found that the temperature, salinity, p H, DO in aquaculture ponds showed a trend of gradual decline trend with the growth of the breeding time, the content of TAN and NO2--N will increase considerably in the middle and later periods of the farming, the content of sulfide will increase slightly in the early stage of the breeding, chl.a will increase obviously as the breeding time developing; Bait casting quantity has significant effects to p H, DO, NO2--N in aquaculture ponds;Shrimp body length growth rate significantly influenced by factors from strong to weak in turns are NO2--N, sulfide（H）, TAN, salinity（S） and p H;But the water temperature and DO had little influence on shrimp growth rate. According to the result of factor analysis, concluded that the shrimp body length growth rate and main physical and chemical factor regression equation is: L=0.021*F1+012*F2+0.066（R₂=0.850）, F1=0.064*T+0.081*S+0.15*P+0.069*D+0.299*A-0.449*N+0.411*H F2=0.269*T+0.331*S+0.227*P+0.121*D-0.585*A+0.141*N-0.164*H。Producers should monitor and regulate the NO2--N（N）, sulfide（H）, TAN salinity（S） and p H especially in the process of breeding, according to the change of the physical and chemical factors, reference the relationship between daily amount of bait casting quantity and the physical and chemical factors, formulate daily amount of bait casting technical proposal; By controlling the change of water frequency and splashing biological reagents and so on,regulate water environment of aquaculture ponds keep in suitable condition.