CAJ | 학술논문

通过北冰洋西部楚科奇海盆M03孔晚第四纪以来生源沉积物,有孔虫丰度和冰筏碎屑(Ice-Rafted Detritus,IRD)的综合研究表明,海洋氧同位素(Marine Isotope Stage,MIS)7期以来,碳酸钙(CaCO_3)含量和浮游有孔虫丰度在间冰期的增加和冰期的降低,分别指示大西洋水输入的加强和减弱.而有机碳(TOC)和生源蛋白石(Biogenic Opal)含量的变化可能主要与输入到海底的TOC降解和Opal溶解作用与底层水中的溶解氧有关.间冰期低的TOC和Opal含量可能反映楚科奇海盆海冰覆盖减少,营养盐供给多,表层生产力增加,通气作用好,底层水富氧,降解和溶解作用增强,保存在沉积物中的TOC和Opal减少;而冰期相对高的TOC和Opal含量可能反映楚科奇海盆海冰覆盖时间较长,营养盐供给少,表层生产力较低,通气作用差,底层水少氧,降解和溶解作用减弱,保存在沉积物中的TOC和Opal增多.
통과북빙양서부초과기해분M03공만제사기이래생원침적물,유공충봉도화빙벌쇄설(Ice-Rafted Detritus,IRD)적종합연구표명,해양양동위소(Marine Isotope Stage,MIS)7기이래,탄산개(CaCO_3)함량화부유유공충봉도재간빙기적증가화빙기적강저,분별지시대서양수수입적가강화감약.이유궤탄(TOC)화생원단백석(Biogenic Opal)함량적변화가능주요여수입도해저적TOC강해화Opal용해작용여저층수중적용해양유관.간빙기저적TOC화Opal함량가능반영초과기해분해빙복개감소,영양염공급다,표층생산력증가,통기작용호,저층수부양,강해화용해작용증강,보존재침적물중적TOC화Opal감소;이빙기상대고적TOC화Opal함량가능반영초과기해분해빙복개시간교장,영양염공급소,표층생산력교저,통기작용차,저층수소양,강해화용해작용감약,보존재침적물중적TOC화Opal증다.
An integrated study was carried out on biogenic sediments, foraminiferal abundance and icerafted detritus (IRD) of core M03 in the Chukchi Basin, western Arctic Ocean to investigate preservation conditions of biogenic components and environmental changes during the late Quaternary. Our results show that since Marine Isotope Stage (MIS) 7, calcium carbonate (CaCO_3)and planktonic foraminiferal abundance increased and decreased during interglacial and glacial periods, respectively, which indicate the Atlantic Water input intensified and weakened in those intervals. However, variations in total organic carbon (TOC) and biogenic opal (opal) contents were primarily associated with the degradation and dissolution of TOC and opal transported to on seafloor and dissolved oxygen level in bottom water. During interglacial periods, low TOC and opal contents suggest that although lessening sea ice coverage and more nutrition supply enhanced sea surface productivity, well-ventilated and oxygenated bottom water, together with reinforcing degradation and dissolution, resulted in decreasing TOC and opal contents preserved in the sediments. During glacial periods, high TOC and opal contents suggest that although extensive sea ice coverage and short of nutrition supply reduced sea surface productivity, bad-ventilated and anoxic bottom water, together with weakening degradation and dissolution, led to increasing TOC and opal contents preserved in the sediments.