CAJ | 학술논문

在蟹塘稳产条件下，为减缓水体氮、磷负荷压力，采用小塘试验法，以常规生产措施为对照（即螺蛳基础用量6000 kg／hm2、外源商品饲料4500 kg／hm2），以蛋白质含量为核算标准，通过增加螺蛳的用量替代商品饲料的减少用量，设计了螺蛳蛋白替代商品饲料蛋白的5个不同比例处理，分别为0％、25％、50％、75％、100％，测定了中华绒螯蟹产量、塘内水体氮、磷含量等指标，研究了内源螺蛳饲料替代外源商品饲料的不同比例对中华绒螯蟹产量和水质的影响。试验结果表明，蟹塘螺蛳常规用量（6000 kg／hm2）条件下，中华绒螯蟹产量、去除饲料投入的毛利润与螺蛳替代外源饲料比例均呈开口向下的一元二次曲线相关，且相关性达显著水平；与对照相比，增加螺蛳投喂量、减少外源饲料用量，蟹塘水体无机氮含量呈下降的变化趋势，对无机磷含量影响较小，但整个养殖过程的水样无机氮含量中位数值符合5类水标准要求；无机磷含量中位数值符合3类水标准要求；综合产量、水体养分含量、经济效益等因素，在蟹塘溶氧充足条件下，外源饲料的适宜可替代比例为37．85％～51．25％，按螺蛳替代饲料比例为40％条件计算，即饲料用量2700 kg／hm2、螺蛳用量14550 kg／hm2。
재해당은산조건하，위감완수체담、린부하압력，채용소당시험법，이상규생산조시위대조（즉라사기출용량6000 kg／hm2、외원상품사료4500 kg／hm2），이단백질함량위핵산표준，통과증가라사적용량체대상품사료적감소용량，설계료라사단백체대상품사료단백적5개불동비례처리，분별위0％、25％、50％、75％、100％，측정료중화융오해산량、당내수체담、린함량등지표，연구료내원라사사료체대외원상품사료적불동비례대중화융오해산량화수질적영향。시험결과표명，해당라사상규용량（6000 kg／hm2）조건하，중화융오해산량、거제사료투입적모리윤여라사체대외원사료비례균정개구향하적일원이차곡선상관，차상관성체현저수평；여대조상비，증가라사투위량、감소외원사료용량，해당수체무궤담함량정하강적변화추세，대무궤린함량영향교소，단정개양식과정적수양무궤담함량중위수치부합5류수표준요구；무궤린함량중위수치부합3류수표준요구；종합산량、수체양분함량、경제효익등인소，재해당용양충족조건하，외원사료적괄의가체대비례위37．85％～51．25％，안라사체대사료비례위40％조건계산，즉사료용량2700 kg／hm2、라사용량14550 kg／hm2。
Snail (Bellamya quadrata) was fed Chinese mitten handed crab (Eriocheir sinensis) as the re‐placement of commercial feed to mitigate nitrogen and phosphorus load in water in culture ponds .Chinese mitten handed crab was reared in a small pond ,and fed snails (a total of 6000 kg/hm2 ) and commercial feed (a total of 4500 kg/hm2 ) as a control group ,and fed the diets containing 0% ,25% ,50% ,75% ,and 100% of snails in the treatment groups to evaluate the effects of snail substitution ratios on yield ,water quality and economic benefits in Chinese mitten handed crab culture .Results showed that there was a quadratic curve relationship between the crab yield and snail substitution percentage ,indicating that crab yields and gross profits were all shown to be significant correlation with snail substitution ratios .Increase in the ratios of snail led to decrease in nitrogen contents in the water in the treatment groups while the phosphorus contents in the water in the treatment groups were less affected by the substitution ratios of snails .The median value of total nitrogen content in waters in the treatment groups were all lower than the standard of V water quality ,and the median value of total phosphorus content were all lower than the standard of Ⅲ water quality in the treatment groups .Comprehensive analysis of effects of replacement of commercial feed by snails on yields ,nutrients contents ,and economic benefits revealed that the optimal snail substitution ratios were recommended to be 37 .85% -51 .25% ,if substitution ratio was calculated by 40% ,the optimal snail feeding rate w as 14 550 kg/hm2 ,and the commercial feed 2700 kg/hm2 .