【摘要】 通过在不同养殖阶段采集四指马鲅养殖场三口池塘内的水样、底泥、生物及饲料等样品,测定其氮磷物质含量,分析不同类型氮磷物质的投入与输出量,总结四指马鲅池塘养殖系统内的氮磷收支特征,探讨四指马鲅冬棚养殖池塘内的水质变动规律,为四指马鲅的健康养殖提供参考。在实验期间, P1、P2、P3三口池塘水体氨氮含量在3月份达到最大值(0.39 mg·L^–1),硝态氮、总氮含量在5月时达到峰值(11.53 mg·L^–1和13.06 mg·L^–1),在5月份拆除冬棚后养殖水体中的硝态氮和总氮含量分别降低至5.04 mg·L^–1和6.45 mg·L^–1,下降趋势明显。亚硝态氮含量一直处于增加趋势,在实验结束时达到最大值0.59 mg·L^–1,显著高于初始含量0.006 mg·L^–1（P<0.05）。水体中的颗粒有机质含量（POM）和化学需氧量（COD）在养殖期间呈上升趋势。在实验结束时, POM和COD含量分别达到0.17 g·L^–1和4.88 mg·L^–1。四指马鲅池塘养殖系统内饲料和进水是主要的氮、磷输入项。实验期间,饲料氮和磷的输入分别占总量的95.97%和96.71%。底泥、渔获品和末期水体是主要氮磷输出项。其中,底泥氮磷输出分别占总量的66.06%和66.73%,渔获品的氮磷比例分别为20.80%和23.98%。池塘养殖系统中渔获物氮和磷的相对利用率分别为21.44%和24.76%。四指马鲅养殖过程中,饲料成本最高,其次为电费成本。平均养殖收益为45.16万元·ha^–1,成本利润率为53.64%。在珠三角冬棚养殖四指马鲅池塘中,氮磷沉积较严重,水质条件较差,增氧效率较低,能耗成本高,在冬棚养殖中后期应注意对池塘水体的调控。更多还原

【Abstract】 The researchers investigated the input and output fluxes of various nitrogen（N） and phosphorus（P） compounds to characterize the N and P balance in the Elentheronema tetradactylum farming system. During the study, the concentrations of N and P were measured in water, fish and diet samples. Throughout the experiment, the highest concentration of ammonia nitrogen（NH₄⁺-N） in the water of E. tetradactylum farming pond was observed in March, reaching 0.39 mg·L^–1. In May, the concentrations of nitrate nitrogen（NO₃^--N） and total nitrogen（TN） peaked at 11.53 mg·L^–1 and 13.06 mg·L^–1, respectively. After the dismantling of the winter greenhouse, the concentrations of NO₃^--N and TN in the pond water decreased to 5.04 mg·L^–1 and 6.45 mg·L^–1, respectively, indicating a statistically significant downward trend. In contrast, the nitrite nitrogen（NO₂^--N） concentrationcontinued to increase, reaching a maximum value of 0.59 mg·L^–1 at the end of the experiment. The concentrations of particulate organic matter（POM） and chemical oxygen demand（COD） in the water showed an increasing trend during the farming period, with average values of 0.17 g·L^–1 and 4.88 mg·L^–1, respectively. Regarding nutrient inputs, feed and inflow-water were identified as the primary sources of N and P in the E. tetradactylum farming pond system. Throughout the experiment, N and P input from the diet accounted for 95.97% and 96.71% of the total inputs, respectively. Sediment accumulation, fish harvest, and pond water constituted the main pathways of N and P output. Specifically, sediment accounted for 66.06% and 66.73% of the total N and P outputs, respectively, while fish harvest accounted for 20.80% and 23.98%, respectively. The relative utilization efficiencies of N and P for fish growth were 24.77% and 21.63%, respectively. In terms of economic performance, feed cost was the highest during the E. tetradactylum farming process, followed by electricity. The average farming income was ￥451,600·ha^–1, with an average cost-profit ratio of 53.64%. This study revealed severe N and P deposition in the E. tetradactylum farming system, which led to poor water quality, low oxygenation efficiency, and high energy consumption. Therefore, it is imperative to strengthen the regulation of pond water quality during the later stages of E. tetradactylum farming.更多还原