参虾生态养殖池塘系统氮磷收支、赋存与分布特征研究

RESEARCH ON BUDGETS,OCCURRENCE,AND DISTRIBUTION OF NITROGEN AND PHOSPHORUS IN ECOLOGICAL AQUACULTURE PONDS FOR SEA CUCUMBER AND SHRIMP

为研究生态养殖对池塘氮磷收支、赋存与分布特征影响,采用陆基网式围隔,设置仿刺参(Apostichopus japonicus)(密度:10、15 ind./m^(2))和中国明对虾(Fenneropenaeus chinensis)(密度:0、2、4、8 ind./m^(2))不同放养密度组合。结果表明:收获各组刺参个体重、成活率均无显著差异(P>0.05)。对虾个体重、成活率均较低,且差异显著(P<0.05)。换水是系统氮磷收支主要途径。水层、刚毛藻、渗漏、底质积累、参、虾、吸附等收支都相对较小,组间差异均不显著(P>0.05)。系统水环境氮磷负荷量分别为N-0.7 g/m^(2)、P-0.5 g/m^(2)。系统沉积物氮磷含量呈明显季节性变化,其中总氮(TN)、铵态氮(NH_(4)^(+)-N)、总磷(TP)、有机态磷(简称O-P)含量季节性变化趋势基本一致,即5月、11月低,7月、9月高。特征性磷季节性变化趋势和垂直分布趋势较复杂。相关性分析结果显示,沉积物特征性磷的赋存和分布与TP、TN、NH4+-N含量密切相关。初步揭示出不投喂参虾生态养殖系统氮磷变化规律,以期为海水绿色生态养殖提供基础理论依据。

The effects of ecological aquaculture on budgets,occurrence,and distribution of nitrogen and phosphorus in aquaculture ponds for sea cucumber and shrimp were studied using a land-based network enclosure tracking system.Sea cucumber Apostichopus japonicus(density:10,15 ind./m^(2))and shrimp Fenneropenaeus chinensis(density:0,2,4,8 ind./m^(2))were selected for experiment.Results show that the harvested showed no significant difference in the weight and survival rate of A.japonicus among group(P>0.05).The weight and survival rate of F.chinensis were relatively low with significant difference(P<0.05).Water exchange was the main pathway for nitrogen and phosphorus budgets in the system.The budgets of water layer,Chladophora,leakage,sediment accumulation,A.japonicus,F.chinensis,and adsorption were relatively small,and no significant difference among groups(P>0.05).The nitrogen and phosphorus loads in the water environment of the system were-0.7 g/m^(2) and-0.5 g/m^(2),respectively.The nitrogen and phosphorus contents in the sediment of the system showed significant seasonal changes,and the seasonal variation trends of total nitrogen(TN),ammonium nitrogen(NH4+-N),total phosphorus(TP),and organic phosphorus(O-P)content were basically consistent,with low values in May and November and high values in July and September.The seasonal variation trend and vertical distribution trend of characteristic phosphorus were more complex.The correlation analysis showed that the occurrence and distribution of characteristic phosphorus in sediments were closely related to the content of TP,TN,and NH_(4)^(+)-N.This study preliminarily revealed the changes in nitrogen and phosphorus in the ecological aquaculture system without feeding A.japonicus and F.chinensis,to provide a basic theoretical basis for green ecological aquaculture in seawater.