繁茂膜海绵滤食养殖水体中过剩饵料的研究

Filtered removal of residual diets in controlled aquaculture system by marine sponge Hymeniacidon perleve

繁茂膜海绵(Hymeniacidon perleve)可滤食养殖水体中的残饵。对活体饵料新月菱形藻(Natzchia closterum),在无营养盐条件,5 g鲜重海绵处理300 mL,藻数量为1.62×106/mL的藻液240 h后,处理组藻的平均浓度仅为对照组的2.9%,为初始浓度的17.2%;在有营养盐条件,5g鲜重海绵处理300 mL,藻数量为0.87×106mL-1的藻液220 h后,对照组的藻仍处于指数生长期,此时处理组藻的平均浓度仅为对照组的0.05%,为初始浓度的64.4%。对死体海参饵料—藻粉和鱼粉蛋白等,由于海绵的滤食作用,海水中颗粒物的浓度随时间增加而呈指数曲线降低。1.5 g鲜重海绵处理200 mL,含200 mg/L海参饵料的海水,在第4d时,海绵已滤食72.6%的颗粒物,有机颗粒物的最大比截留速率为21.6×10-3/d.L。同时,海绵的生物量明显增加。

Sponges （Porifera） are sessile, filter-feeding multi-cellular animals. The aim of this study was to investigate the potential of the marine sponge Hymeniacidon perleve to filtered removal of superfluous/residual diets of water volume in controlled aquaculture system. Two types of diets were studied, including living diet-marine algae Natzchia closterum, and the dead organic particle diets for sea cucumbers-mixture of algal powder and fish protein powder. The average algal cell density in treated group was 2.9% of that in control, and 17.2% of initial density when 5 g fresh sponge biomass was used to filter 300 mL algal cell suspension at 1.62 ×10^6/mL after 240 li. When extra nutrients were added, the average algal cell density in treated group was 64.4% of initial density, and 0.05% of that in control after 220 h filtering of 300 ml algal cell suspension at 0.87 ×10^6/mL by 5 g fresh sponge biomass. While 1.5 g fresh sponge biomass was used to falter 200 mL seawater containing 200 mg/L dead organic particle diet for sea cucumbers, the organic particle concentration decreased exponentially with time. On fourth day, the sponge was removed 72.6% of the organic particles, with a maximum specific retaining rate of 21.6 × 10^-3/d·L. As a result, a maximum remove of 22% in sponge biomass was observed per day.