摘要
本文研究了大型底栖动物对富营养化造成的养分动态和波罗的海浮游-底栖耦合过程的生态作用。大型底栖动物活动通常对沉积物生物地球化学变化具有显著影响,并且能够促进与富营养化相抵消的反硝化作用和沉积物磷持留过程的增强。大型动物对这些过程的影响程度取决于动物的密度和功能群组成。与无大型动物的沉积层相比,大型动物活动对沉积物营养动态的影响还将导致生物沉积出流中较高的N:P比例。富营养化引起的缺氧情况下,内源性养分物质负荷增加的原因包括沉积物生物地球化学过程的改变和生物扰动性大型动物的减少或缺失使得这些动物活动对波罗的海生态系统的自净过程的促进作用下降。
This article focuses on the ecological role of benthic macrofauna on nutrient dynamics and benthic-pelagic coupling in the Baltic Sea with relation to eutrophication.Generally,benthic macrofaunal activities have large effects on sediment biogeochemistry and often with stimulatory effects on processes that counteract eutrophication,i.e.,denitrification and increased phosphorus retention of the sediment.The degree of faunal impact on such processes varies depending on faunal density and functional group composition.The effect of macrofaunal activities on sediment nutrient dynamics can also result in a higher nitrogen:phosporus ratio of the sediments efflux compared with sediments without macrofauna.Increased internal nutrient loading during eutrophication-induced anoxia is suggested to be caused both by altered sediment biogeochemical processes and through reduced or lost bioturbating macrofauna and thereby a reduced stimulatory effect from their activities on natural purification processes of the Baltic Sea ecosystem.
