نتایج جستجو برای: isotope ratio

تعداد نتایج: 530028  

2018
Susan R. Kennedy Todd E. Dawson Rosemary G. Gillespie

The Hawaiian Islands offer a unique opportunity to test how changes in the properties of an isolated ecosystem are propagated through the organisms that occur within that ecosystem. The age-structured arrangement of volcanic-derived substrates follows a regular progression over space and, by inference, time. We test how well documented successional changes in soil chemistry and associated veget...

Journal: :Proceedings of the National Academy of Sciences of the United States of America 1974
L M Libby L J Pandolfi

The stable isotope ratios of carbon, oxygen, and hydrogen have been measured for a German oak in wood samples of roughly three years each, for the years 1712-1954 A.D., and correlated with the existing weather records from England, Basel, and Geneva to evaluate the empirical temperature coefficients. Isotope ratios in a second official oak, measured for the years 1530-1800 A.D., show the cold t...

2014
Linn S. Lehnert Stephanie Kramer-Schadt Sophia Schönborn Oliver Lindecke Ivo Niermann Christian C. Voigt

Over recent years, it became widely accepted that alternative, renewable energy may come at some risk for wildlife, for example, when wind turbines cause large numbers of bat fatalities. To better assess likely populations effects of wind turbine related wildlife fatalities, we studied the geographical origin of the most common bat species found dead below German wind turbines, the noctule bat ...

2013
Anna Törnroos Marie C. Nordström Erik Bonsdorff

Due to human impact, there is extensive degradation and loss of marine habitats, which calls for measures that incorporate taxonomic as well as functional and trophic aspects of biodiversity. Since such data is less easily quantifiable in nature, the use of habitats as surrogates or proxies for biodiversity is on the rise in marine conservation and management. However, there is a critical gap i...

Journal: :Ecological applications : a publication of the Ecological Society of America 2008
Jeffrey F Kelly Matthew J Johnson Suzanne Langridge Mary Whitfield

A primary constraint on effective conservation of migratory animals is our inability to track individuals through their annual cycle. One such animal is the endangered southwestern subspecies of the Willow Flycatcher, which is difficult to distinguish from conspecifics. Identifying wintering regions used by the endangered subspecies would be an important step in formulating an effective conserv...

2009
Eitaro Wada

In the past 20 years, rapid progress in stable isotope (SI) studies has allowed scientists to observe natural ecosystems from entirely new perspectives. This report addresses the fundamental concepts underlying the use of the SI ratio. The unique characteristics of the SI ratio make it an interdisciplinary parameter that acts as a chemical fingerprint of biogenic substances and provides a key t...

Journal: :Marine pollution bulletin 2012
S E Lewis J E Brodie M T McCulloch J Mallela S D Jupiter H Stuart Williams J M Lough E G Matson

Coral cores were collected along an environmental and water quality gradient through the Whitsunday Island group, Great Barrier Reef (Australia), for trace element and stable isotope analysis. The primary aim of the study was to examine if this gradient could be detected in coral records and, if so, whether the gradient has changed over time with changing land use in the adjacent river catchmen...

Journal: :Analytica chimica acta 2012
N Dordevic R Wehrens G J Postma L M C Buydens F Camin

Wine derives its economic value to a large extent from geographical origin, which has a significant impact on the quality of the wine. According to the food legislation, wines can be without geographical origin (table wine) and wines with origin. Wines with origin must have characteristics which are essential due to its region of production and must be produced, processed and prepared, exclusiv...

Journal: :Trends in biotechnology 2005
Claudia Birkemeyer Alexander Luedemann Cornelia Wagner Alexander Erban Joachim Kopka

Metabolome analysis technologies are still in early development because, unlike genome, transcriptome and proteome analyses, metabolome analysis has to deal with a highly diverse range of biomolecules. Combinations of different analytical platforms are therefore required for comprehensive metabolomic studies. Each of these platforms covers only part of the metabolome. To establish multiparallel...

Journal: :American journal of physical anthropology 1992
C S Larsen M J Schoeninger N J van der Merwe K M Moore J A Lee-Thorp

Measurement of carbon and nitrogen stable isotope ratios (delta 13C and delta 15N) in samples of human bone collagen (n = 93) from a temporal series of four prehistoric (early preagricultural, late preagricultural, early agricultural, late agricultural) and two historic (early contact, late contact) periods from the Georgia Bight, a continental embayment on the southeastern U.S. Atlantic coast,...

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