大口黑鲈(Micropterus salmoides)不同养殖模式氮磷收支及养殖效果研究

为了揭示池塘内循环流水养殖模式(Inner-Pond Raceway Aquaculture,IPRA)氮磷收支变化及养殖效果情况,阐明其生态特征及营养物质的来源与归宿,合理评价IPRA的经济与生态效益,通过定期采样计算氮磷的输入和输出项目,同时设置传统常规养殖池塘(usual pond aquaculture,UPA)为对照组。结果表明:(1)两种养殖模式中,饲料是池塘氮、磷输入的主要来源,分别占IPRA和UPA池塘氮输入的95.02%±2.31%和94.57%±1.82%,占两种模式磷输入的93.19%±2.75%和91.81%±4.44%;(2)底泥沉积是氮、磷输出的主要方式,占IPRA和UPA氮输出的45.16%±1.31%和53.98%±1.48%,占磷输出的40.28%±3.19%和59.59%±4.45%,差异显著(P0.05),其次是养殖产出,IPRA渔获物氮输出比例37.73%±0.91%高于UPA的35.07%±0.99%,差异不显著(P0.05),磷输出比例25.50%±1.77%显著高于UPA的20.78%±1.33%(P0.05);(3)IPRA对氮的绝对和相对利用率高于UPA,但差异不显著(P0.05),而对磷的利用率显著高于UPA (P0.05), IPRA提高了养殖对象对氮、磷的吸收利用率;(4) IPRA耗水系数、排水系数及排污系数均显著低于UPA (P0.05),但IPRA养殖效益显著高于UPA (P0.05)。综上所述, IPRA是一种清洁高效的新型养殖模式,可以进行推广应用。本研究旨在为今后更好地开展IPRA水质管理和科学养殖提供数据支撑,同时为IPRA模式在节水生态、经济效益等评价方面提供理论依据。

A COMPARATIVE STUDY ON NITROGEN AND PHOSPHORUS BUDGET AND AQUACULTURE EFFECT OF MICROPTERUS SALMOIDES IN TWO MODES

To discuss the changes of nitrogen and phosphorus budget and aquaculture effect of Inner-Pond Raceway Aquaculture (IPRA) mode, expound its ecological characteristics, nutrient orientation, and rationally evaluate the ecological and economic benefits of IPRA, the input and output of nitrogen and phosphorus were analyzed based on regular sampling. Meanwhile, the usual pond aquaculture (UPA) mode was set as the control treatment. Results show that:(1) Feed was the main source of nitrogen and phosphorus input, accounting for 95.02%±2.31% and 94.57%±1.82% of the nitrogen input, and 93.19%±2.75% and 91.81%±4.44% of the phosphorus input in IPRA and UPA modes respectively. (2) Sediment deposition was the main mode of nitrogen and phosphorus output, accounting for 45.16%±1.31% and 53.98%±1.48% of nitrogen output as well as 40.28%±3.19% and 59.59%±4.45% of phosphorus output in IPRA and UPA in P<0.05, respectively. The second part was the fish output, accounting for 37.73%±0.91% and 35.07%±0.99% of the nitrogen output in IPRA and UPA with P>0.05 and 25.50%±1.77% and 20.78%±1.33% of the phosphorus output in IPRA and UPA with P<0.05, respectively. (3) The relative and absolute utilization rates of nitrogen and phosphorus in IPRA mode were significantly higher than those in UPA (P<0.05). IPRA improved the utilization rates of nitrogen and phosphorus in the breeding objects. (4) The water consumption coefficient, drainage coefficient, and pollution discharge coefficient of IPRA were significantly lower than those of UPA (P<0.05). The profit of IPRA was significantly higher than that of UPA (P<0.05). Above all, the IPRA is a clean and efficient new aquaculture mode, which can be promoted and applied. This study provided a data support for better implementation of water quality management and scientific aquaculture for IPRA in the future, and built a theoretical basis for the evaluation of IPRA in water-saving ecology and other aspects.