浙江象山港牡蛎养殖区沉积物反硝化速率的时空变化及其影响因素  

Spatiotemporal variations and regulators of sediment denitrification rate and in the oyster farm of Xiangshan Bay in Zhejiang Province

作　　者：李雪英 王杰 唐保军[1] 全为民[1] LI Xueying;WANG Jie;TANG Baojun;QUAN Weimin(East China Sea Fisheries Research Institute,Chinese Academy of Fishery Sciences,Shanghai 200090;Institute of Agriculture Science,Sixth Division,Xinjiang Production and Construction Corps,Wujiaqu 831300)

机构地区：[1]中国水产科学研究院东海水产研究所,上海200090 [2]新疆生产建设兵团第六师农业科学研究所,五家渠831300

出　　处：《环境科学学报》2024年第1期311-323,共13页Acta Scientiae Circumstantiae

基　　金：上海市自然科学基金项目(No.19ZR1469900);国家贝类产业技术体系建设项目(No.CARS-49)。

摘　　要：基于15N同位素配对技术和室内模拟实验方法,考察了象山港牡蛎养殖区沉积物反硝化速率的时空变化及其影响因素,分析了牡蛎生物沉积对底质反硝化过程的影响.结果表明,牡蛎养殖区沉积物反硝化速率为(408.66±64.19)~(3873.76±590.41)μmol·m^(-2)·h^(-1),季节变化趋势为秋季>夏季>春季>冬季(p<0.05),牡蛎养殖区((1967.69±1457.84)μmol·m^(-2)·h^(-1))显著高于参照区((933.50±600.52)μmol·m^(-2)·h^(-1))(p<0.05).影响牡蛎养殖区沉积物反硝化速率的主要环境因子分别为海水温度、颗粒有机氮(PON)、颗粒有机碳(POC)、NO_(2)^(-)-N、NO_(3)^(-)-N和沉积物氧化还原电位(ORP)、S^(2-)、总有机氮(TON)、总有机碳(TOC)、NO_(3)^(-)-N.牡蛎生物沉积的沉降可以向底质输入大量的有机质(牡蛎生物沉积速率为(12.26±2.06)mg·ind^(-1)·d^(-1),颗粒物沉降通量为(76.16±3.41)g·m^(-2)·d-1),显著提高了养殖区的沉积物反硝化速率,其影响程度在秋季最高,其次依次为夏季、春季和冬季.牡蛎生物沉积对底质反硝化过程的影响机制为:牡蛎生物沉积向海底释放了大量有机质,为反硝化菌提供了丰富的营养物质,提高了沉积物的还原性,从而促进了底质反硝化过程.This study investigated the spatial and temporal variations of sediment denitrification rate and its key regulators in the oyster farm of Xiangshan Bay through the isotope pairing technique and lab-simulated experiments,and furthermore explored the influencing process of oyster bio-deposition on sediment denitrification and its driving mechanism.The results showed that sediment denitrification rates in the oyster farm area varied from(408.66±64.19)μmol·m^(-2)·h^(-1)to(3873.76±590.41)μmol·m^(-2)·h^(-1)and significantly differed among the four sampling seasons,with the rank in the order as the following:fall>summer>spring>winter(p<0.05).Higher sediment denitrification rate was recorded in the oyster farm area((1967.69±1457.84)μmol·m^(-2)·h^(-1))than in the control area((933.50±600.52)μmol·m^(-2)·h^(-1))(p<0.05).It was found that the key regulators affecting sediment denitrification in the oyster farm area were the abiotic factors of overlying water(temperature,PON,POC,NO_(2)^(-)-N,NO_(3)^(-)-N)and sediment(ORP,S^(2-),TON,TOC,NO_(3)^(-)-N).The study indicated that oyster bio-deposition inputted a larger amount of organic matter(oyster biological deposition rate:(12.26±2.06)mg·ind^(-1)·d^(-1),and particle deposition flux:(76.16±3.41)g·m^(-2)·d^(-1))into bottom sediment,positively facilitated sediment denitrification in the oyster farm area,especially in autumn and followed by summer,spring and winter.It was concluded that oyster bio-deposition supplied a large amount of organic matter that served as nutrients for sediment denitrification bacteria,produced anaerobic and reducing sediment environment,and thus promoted the sediment denitrification process.

关 键 词：牡蛎养殖区 象山港 反硝化 沉积物 环境理化因子 

分 类 号：P76[天文地球—海洋科学] S912[农业科学—水产科学] X52[环境科学与工程—环境工程]