N and P Fluxes in Sediment-Water Interface of Sea Cucumber Ponds Exposed to Three Water Quality Control Methods
LEI Zhaolin1, DANG Ziqiao2, ZHANG Dongsheng1,3, SUN Yahui1, LI Lezhou1, ZHANG Jinyuan4, WANG Yulong1, ZHOU Wei1
1. College of Fisheries and Life Science, Dalian Ocean University, Dalian 116023, China; 2. National Fisheries Technology Extension Center, China Society of Fisheries, Beijing 100000, China; 3. Key Laboratory of Mariculture and Stock Enhancement in North China's Sea, Ministry of Agriculture and Rural Affairs, Dalian Ocean University, Dalian 116023, China; 4. School of Economics and Management, Dalian Ocean University, Dalian 116023, China
Abstract:In order to explore the exchange of N and P nutrients in the sediment-water interface of sea cucumber Apostichopus japonicus ponds (605 m × 85 m)under different water quality control methods, the diffusion flux of N and P nutrients in the sediment-water interface was investigated in water samples collected from the deepest part of the pond 3—5 days before the water change of each pond every month in sea cucumber ponds of Dalian Baofahai Treasures Co., Ltd. in Zhuanghe City(N 39.7866°, E 123.3208°), Liaoning province, under three water quality control methods: natural pond without any aeration system, microporous aeration (air compressor with 0.1 kw/667 m2) and water quality regulator (750 kW/h). It was found that there were variation in NOx- flux range of -36.0—10.8 mg/(m2·d) in natural pond without any aeration system and -12.0—7.8 mg/(m2·d) inmicroporous aeration ponds , negative flux in March, July and August, with the minimal flux value in July [-36.0, -12.0 mg/(m2·d)], and positive [0.6—5.4 mg/(m2·d)] throughout the year in the pond with the water quality regulator. Natural NH4+ fluxes were ranged from -102.6 mg/(m2·d) to 71.4 mg/(m2·d)in natural pond without any aeration system ponds and -90.6—78.0 mg/(m2·d)in bottom aeration aerators, with negative in July and August. However, positive flux was observed in the water quality regulator pond throughout the year, with the change range from 5.4 mg/(m2·d) to 81.6 mg/(m2·d). The PO43- flux was found to be positive throughout the year in the three sea cucumber ponds, with the maximum in July and August, with a variation of 8.6—76.2 mg/(m2·d) in natural tidal ponds, 30.0—73.2 mg/(m2·d) in microporous aeration ponds, and 29.4—50.4 mg/(m2·d) in water quality regulator pond. The N and P flux differences in sediment-water interface were very small in the pond with the water quality regulator compared to the other two ponds. The findings indicated that the water quality regulator contributed to the formation of a stable oxidizing environment at bottom of the ponds and was conducive to release of N and P substances at bottom of the ponds.
雷兆霖, 党子乔, 张东升, 孙亚慧, 李乐洲, 张津源, 王玉龙, 周玮. 3种水质调控方式下参池沉积物—水界面N、P通量的研究[J]. 水产科学, 2021, 40(3): 354-360.
LEI Zhaolin, DANG Ziqiao, ZHANG Dongsheng, SUN Yahui, LI Lezhou, ZHANG Jinyuan, WANG Yulong, ZHOU Wei. N and P Fluxes in Sediment-Water Interface of Sea Cucumber Ponds Exposed to Three Water Quality Control Methods. 水产科学, 2021, 40(3): 354-360.