三疣梭子蟹、凡纳滨对虾和菲律宾蛤仔混养系统氮磷收支的研究

Nitrogen and Phosphorus Budgets of Polyculture System of Portunus trituberculatus,Litopenaeus vannamei and Ruditapes philippinarum

利用海水池塘陆基实验围隔,研究三疣梭子蟹（Portunus trituberculatus）、凡纳滨对虾（Litopenaeus vannamei）和菲律宾蛤仔（Ruditapes philippinarum）不同混养系统的养殖效果以及氮（N）和磷（P）的收支和利用率状况.结果表明：（1）适宜的三疣梭子蟹、凡纳滨对虾和菲律宾蛤仔三元混养,能有效提高三疣梭子蟹养殖的综合效益.（2）投喂的饵料（包括对虾配合饲料与蓝蛤（Aloidis laevis））是系统N、P的主要来源,占N总输入量的84.41％～89.75％和P总输入量的96.64％～98.35％;其次为水层中带入的N、P,占N总输入量的7.14％～11.97％和P总输入量的0.39％～1.11％.N、P的支出主要为底泥积累,占N总支出量的39.88％～57.17％和P总支出量的35.69％～68.45％;其次为养殖生物收获N、P,占总支出的比例分别为16.86％～32.24％和18.72％～33.55％;N的输出渗漏损失较大,水层积累较少,而P的输出水层积累较多,渗漏损失较少.（3）各处理比较,三元混养PLR3组N的利用率显著提高,比其它处理提高了9.95％～15.80％.综合养殖效果和各系统N、P利用率结果,在本研究条件下,蟹、虾、贝混养最优比例为三疣梭子蟹6 ind/m^2、凡纳滨对虾45 ind/m2、菲律宾蛤仔30～60 ind/m^2.

The budgets of nitrogen （N） and phosphorus （P） were studied with land-based enclosures for various polyculture systems of Portunus trituberculatus , Litopenaeus vannamei and Ruditapes phil- ippinarum. The results showed that the feed was the main nitrogen （accounting for 84.41%-89. 75%） and phosphorus （accounting for 96.64%-98. 85%） input in the enclosures while the marine water supply provided 7.14%-11.97% of nitrogen input and 0.39% -1.11% of total phosphorus input. The major output of nitrogen and phosphorus were in the sediments, which accounted for 39.88%-57.17% of the total nitrogen output and 35.69% -68. 45% of total phosphorus output. The biomass harvest compromised 16.86 %-32.24% of total nitrogen output and 18. 72%-33.55% of total phosphorus output. The highest utilization efficiency of nitrogen and phosphorus was observed in the treatment PLRa, followed by PLR4. The treatment giving the best culturing benefit was crabs at 6 ind/m^2 , shrimps at 45 ind/m^2 and clams at 30-60 ind/m^2.