钦州湾近岸网箱养殖期磷的分布特征研究

Study on Distribution Characteristics of Phosphorus in Cage Culture Stage Near Qinzhou Bay，South China

关键词:  钦州湾  网箱养殖  磷  分布

Key words:  Qinzhou Bay  cage culture  phosphorus  distribution

摘要:

为了解钦州湾近岸养殖卵形鲳鲹(Trachinotus ovatus)网箱在不同的养殖期内水体和沉积物中磷(Phosphorus)的分布特征，于2022年5月(养殖投苗期)、7月(养殖高峰期)和10月(养殖收成期)调查该区域并分析水体和表层沉积物中磷的分布规律。结果表明：水体中磷含量在养殖期间呈逐渐升高、表层高于底层的变化趋势，溶解无机磷(Dissolved Inorganic Phosphorus，DIP)是总溶解态磷(Total Dissolved Phosphorus，TDP)的主要赋存形态；在养殖高峰期网箱区出现磷限制情况。表层沉积物中磷含量在养殖高峰期出现较大值，呈养殖高峰期高于养殖收成期和养殖投苗期、网箱区高于非养殖区的分布特征，无机磷(Inorganic Phosphorus，IP)是总磷(Total Phosphorus，TP)的主要赋存形态。网箱养殖期的磷富集指数(P Enrichment Index，PEI)为0.31-1.42，网箱区高于非养殖区，表明钦州湾近岸网箱养殖活动会给沉积环境带来磷污染。高度集约化的养殖活动对水环境和沉积环境质量均有负面影响，针对钦州湾近岸网箱养殖期磷污染情况，需采取科学的调控对策，打造钦州湾生态健康养殖模式，在提升经济价值的同时降低对海洋环境的污染。

Abstract:

In order to understand the distribution characteristics of Phosphorus in water and sediments of Trachinotus ovatus cultured in Qinzhou Bay during different culture periods,the distribution of phosphorus in water and surface sediments was investigated in May (breeding and seeding period),July (breeding peak period) and October (breeding harvest period) in 2022.The results showed that the variation trend of phosphorus content increased gradually during the breeding period,and the content in the surface water was higher than that in the bottom water.Dissolved Inorganic Phosphorus (DIP) was the main form of Total Dissolved Phosphorus (TDP).Phosphorus limitation occurred in the cage area during the peak period of breeding.The phosphorus content in surface sediments showed a larger value during the peak period of culture,and the distribution characteristics of phosphorus content in surface sediments showed that the phosphorus content in culture peak period was higher than that in culture harvest period and culture seedling stage,and that in cage area was higher than that in non-culture area.Inorganic Phosphorus (IP) was the main occurrence form of Total Phosphorus (TP).The P Enrichment Index (PEI) during cage culture period was 0.31-1.42,and the cage area was higher than the non-culture area,indicating that the offshore cage culture activities in Qinzhou Bay would bring phosphorus pollution to the sedimentary environment.Highly intensive culture activities have a negative impact on the quality of both water environment and sedimentary environment.In view of the phosphorus pollution in the coastal cage culture period of Qinzhou Bay,it is necessary to take scientific control measures to create an ecological and healthy culture model in Qinzhou Bay,improve economic value and reduce pollution to the marine environment.