Artificial fish nests are set in Lukou section and Hengyang section of Xiangjiang River from March 20 to May 10, 2019. The structure of artificial fish nest is bamboo frame, with the size of 2.5 m × 5.0 m × ...Artificial fish nests are set in Lukou section and Hengyang section of Xiangjiang River from March 20 to May 10, 2019. The structure of artificial fish nest is bamboo frame, with the size of 2.5 m × 5.0 m × 4 and a unit frame area of 60 m<sup>2</sup>. A total of 58,201 eggs were collected by 24 monitoring times, of which 30,441 were from Lukou and 27,760 from Hengyang. 3831 fish eggs identify 8 fish species using morphological or molecular biological methods. The results showed that the number of eggs peaked from the 8<sup>th</sup> day to the 24<sup>th</sup> day after the nest entered the water, and then decreased rapidly. There was significant negative correlation between egg number in per m<sup>2</sup> fish nest and days of fish nest (P < 0.01). The economic benefits of artificial fish nests were RMB 11.81 million. The artificial fish nest can not only increase the population of fish, but also has significant economic benefits.展开更多
本研究分析了水产养殖和垂钓中饲料、窝料、饵料、水样及水产品中地西泮(Diazepam,DZP)的存在情况,并建立了在线净化-液相色谱串联质谱定量检测方法。结果表明DZP含量在0.5~20.0μg/L间线性良好,相关系数(r^(2))均大于0.999;饵料、水样...本研究分析了水产养殖和垂钓中饲料、窝料、饵料、水样及水产品中地西泮(Diazepam,DZP)的存在情况,并建立了在线净化-液相色谱串联质谱定量检测方法。结果表明DZP含量在0.5~20.0μg/L间线性良好,相关系数(r^(2))均大于0.999;饵料、水样和水产品中定量限(Limit of quantitation,LOQ)分别为1.0μg/kg、0.5μg/L、1.0μg/kg;3种基质中1.0μg/kg、5.0μg/kg和10.0μg/kg 3个浓度水平的加标回收率分别为85.2%~106.5%、82.3%~108.0%、90.7%~116.0%,相对标准偏差(Relative standard deviation,RSD)分别为3.6%~5.1%、2.7%~4.3%、2.1%~2.6%。通过调查发现,7份养殖用饲料中均未检出DZP;28份垂钓中使用的窝料、饵料检出率达66.7%,浓度为2.2~213090.0μg/kg;10份诱鱼剂中均检出DZP,检出率达100%,浓度为637000.0~3471000.0μg/kg;27份水样中DZP检出率达85.2%,浓度为0.4~9.8μg/L和71份淡水鱼中DZP的检出率为54.9%,浓度为0.5~21.8μg/kg。由此可见窝料、饵料及诱鱼剂的使用可能是水体和水产品中DZP频繁检出的重要原因之一,对消费者食用安全和水产养殖行业的健康发展均具有潜在风险,亟需加强DZP监管和监测。展开更多
文摘Artificial fish nests are set in Lukou section and Hengyang section of Xiangjiang River from March 20 to May 10, 2019. The structure of artificial fish nest is bamboo frame, with the size of 2.5 m × 5.0 m × 4 and a unit frame area of 60 m<sup>2</sup>. A total of 58,201 eggs were collected by 24 monitoring times, of which 30,441 were from Lukou and 27,760 from Hengyang. 3831 fish eggs identify 8 fish species using morphological or molecular biological methods. The results showed that the number of eggs peaked from the 8<sup>th</sup> day to the 24<sup>th</sup> day after the nest entered the water, and then decreased rapidly. There was significant negative correlation between egg number in per m<sup>2</sup> fish nest and days of fish nest (P < 0.01). The economic benefits of artificial fish nests were RMB 11.81 million. The artificial fish nest can not only increase the population of fish, but also has significant economic benefits.
文摘本研究分析了水产养殖和垂钓中饲料、窝料、饵料、水样及水产品中地西泮(Diazepam,DZP)的存在情况,并建立了在线净化-液相色谱串联质谱定量检测方法。结果表明DZP含量在0.5~20.0μg/L间线性良好,相关系数(r^(2))均大于0.999;饵料、水样和水产品中定量限(Limit of quantitation,LOQ)分别为1.0μg/kg、0.5μg/L、1.0μg/kg;3种基质中1.0μg/kg、5.0μg/kg和10.0μg/kg 3个浓度水平的加标回收率分别为85.2%~106.5%、82.3%~108.0%、90.7%~116.0%,相对标准偏差(Relative standard deviation,RSD)分别为3.6%~5.1%、2.7%~4.3%、2.1%~2.6%。通过调查发现,7份养殖用饲料中均未检出DZP;28份垂钓中使用的窝料、饵料检出率达66.7%,浓度为2.2~213090.0μg/kg;10份诱鱼剂中均检出DZP,检出率达100%,浓度为637000.0~3471000.0μg/kg;27份水样中DZP检出率达85.2%,浓度为0.4~9.8μg/L和71份淡水鱼中DZP的检出率为54.9%,浓度为0.5~21.8μg/kg。由此可见窝料、饵料及诱鱼剂的使用可能是水体和水产品中DZP频繁检出的重要原因之一,对消费者食用安全和水产养殖行业的健康发展均具有潜在风险,亟需加强DZP监管和监测。
