کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1045215 944805 2015 14 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Reconstruction of late Quaternary paleohydrologic conditions in southeastern British Columbia using visible derivative spectroscopy of Cleland Lake sediment
ترجمه فارسی عنوان
بازسازی شرایط اواخر کواترنر پائئوهیدرولوژیک در جنوب شرقی بریتیش کلمبیا با استفاده از طیف سنجی مشتق از رسوبات دریاچه کللند
کلمات کلیدی
طیف سنجی مشتق قابل مشاهده، بهره وری، سطح دریاچه، هولوسن، رنگدانه، بریتیش کلمبیا،
موضوعات مرتبط
مهندسی و علوم پایه علوم زمین و سیارات زمین شناسی
چکیده انگلیسی
Visible derivative spectroscopy (VDS) analysis of sediment from Cleland Lake, Southeastern British Columbia provides a reconstruction of paleolimnological productivity and hydrologic change during the past 14,000 calibrated 14C years before present (cal yr BP). The first five principal components (PC) of the VDS data explain 97% of the variance in the VDS data set. Four PCs correlate with standard reflectance derivative spectra for diatom, dinoflagellate algae, and cyanophyte pigments that record ecological change, while two PCs are paleohydrologic indicators. Dinoflagellate algae are predominant from 11,600 to 8600 cal yr BP then decrease to low levels after ~ 8500 cal yr BP. PCs 3-5 represent variations in cyanophyte abundance and exhibit peaks from 14,000 to 11,600, 14,000 to 9500, and 6100 to 5400 cal yr BP, respectively. Conditions shifted toward favoring diatoms around 9400 and lasted until 170 cal yr BP. Higher dinoflagellate-related pigment concentrations suggest a lower lake level from 11,600 to 8600 cal yr BP, followed by higher water levels and wetter conditions after 8500 cal yr BP. We propose that drier conditions transitioning from the late glacial into the Holocene were caused by summer insolation-driven, non-linear feedbacks between the northern hemisphere subtropical high-pressure systems, vegetation, and soil moisture.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Quaternary Research - Volume 83, Issue 3, May 2015, Pages 531-544
نویسندگان
, , , , ,