中文版 | English

在结果中检索

GSTDTAP

浏览/检索结果: 共20条，第1-10条 帮助

已选(0)清除 条数/页：   排序方式：
Hydrothermal (NN)-N-15-N-15 abundances constrain the origins of mantle nitrogen 期刊论文
NATURE, 2020, 580 (7803) : 367-+
作者:  Zhao, Steven;  Jang, Cholsoon;  Liu, Joyce;  Uehara, Kahealani;  Gilbert, Michael;  Izzo, Luke;  Zeng, Xianfeng;  Trefely, Sophie;  Fernandez, Sully;  Carrer, Alessandro;  Miller, Katelyn D.;  Schug, Zachary T.;  Snyder, Nathaniel W.;  Gade, Terence P.;  Titchenell, Paul M.;  Rabinowitz, Joshua D.;  Wellen, Kathryn E.
收藏  |  浏览/下载：14/0  |  提交时间：2020/05/13

Nitrogen is the main constituent of the Earth'  s atmosphere, but its provenance in the Earth'  s mantle remains uncertain. The relative contribution of primordial nitrogen inherited during the Earth'  s accretion versus that subducted from the Earth'  s surface is unclear(1-6). Here we show that the mantle may have retained remnants of such primordial nitrogen. We use the rare (NN)-N-15-N-15 isotopologue of N-2 as a new tracer of air contamination in volcanic gas effusions. By constraining air contamination in gases from Iceland, Eifel (Germany) and Yellowstone (USA), we derive estimates of mantle delta N-15 (the fractional difference in N-15/N-14 from air), N-2/Ar-36 and N-2/He-3. Our results show that negative delta N-15 values observed in gases, previously regarded as indicating a mantle origin for nitrogen(7-10), in fact represent dominantly air-derived N-2 that experienced N-15/N-14 fractionation in hydrothermal systems. Using two-component mixing models to correct for this effect, the (NN)-N-15-N-15 data allow extrapolations that characterize mantle endmember delta N-15, N-2/Ar-36 and N-2/He-3 values. We show that the Eifel region has slightly increased delta N-15 and N-2/Ar-36 values relative to estimates for the convective mantle provided by mid-ocean-ridge basalts(11), consistent with subducted nitrogen being added to the mantle source. In contrast, we find that whereas the Yellowstone plume has delta N-15 values substantially greater than that of the convective mantle, resembling surface components(12-15), its N-2/Ar-36 and N-2/He-3 ratios are indistinguishable from those of the convective mantle. This observation raises the possibility that the plume hosts a primordial component. We provide a test of the subduction hypothesis with a two-box model, describing the evolution of mantle and surface nitrogen through geological time. We show that the effect of subduction on the deep nitrogen cycle may be less important than has been suggested by previous investigations. We propose instead that high mid-ocean-ridge basalt and plume delta N-15 values may both be dominantly primordial features.


  
Spatial mapping of the provenance of storm dust: Application of data mining and ensemble modelling 期刊论文
ATMOSPHERIC RESEARCH, 2020, 233
作者:  Gholami, Hamid;  Mohamadifar, Aliakbar;  Collins, Adrian L.
收藏  |  浏览/下载：5/0  |  提交时间：2020/07/02
Dust provenance  Spatial modelling  Data mining algorithms  Multicollinearity  Receiver operating characteristic  Ensemble modelling  R software  
Seed origin drives differences in survival and growth traits of cork oak (Quercus suber L.) populations 期刊论文
FOREST ECOLOGY AND MANAGEMENT, 2019, 448: 267-277
作者:  Sampaio, Teresa;  Goncalves, Elsa;  Patricio, Maria S.;  Cota, Tania M.;  Helena Almeida, M.
收藏  |  浏览/下载：7/0  |  提交时间：2019/11/27
Mediterranean oak  Fitness surrogate traits  Population variation  Provenance trials  Local adaptation  Mixed models  
Guiding seed source selection for the production of tropical dry forest trees: Coulteria platyloba as study model 期刊论文
FOREST ECOLOGY AND MANAGEMENT, 2019, 446: 105-114
作者:  Luna-Nieves, Adriana L.;  Meave, Jorge A.;  Gonzalez, Edgar J.;  Cortes-Flores, Jorge;  Ibarra-Manriquez, Guillermo
收藏  |  浏览/下载：8/0  |  提交时间：2019/11/27
Germination  Parental tree  Phenotypic variation  Piecewise structural equation modelling  Provenance  Reforestation  Restoration  Seed scarification  Seed supply  Seedling quality  
Native-source climate determines the Douglas-fir potential of adaptation to drought 期刊论文
FOREST ECOLOGY AND MANAGEMENT, 2019, 444: 9-20
作者:  Chauvin, Thibaud;  Cochard, Herve;  Segura, Vincent;  Rozenberg, Philippe
收藏  |  浏览/下载：7/0  |  提交时间：2019/11/27
Cavitation resistance  Climate change  Common garden  Evolutionary adaptation  Hydraulic traits  Phenotypic plasticity  Provenance variation  Pseudotsuga mensiesii (Mirb.) Franco  
Genetic diversity and differentiation among provenances of Prosopis flexuosa DC (Leguminosae) in a progeny trial: Implications for arid land restoration 期刊论文
FOREST ECOLOGY AND MANAGEMENT, 2019, 443: 59-68
作者:  Bessega, C.;  Cony, M.;  Saidman, B. O.;  Aguilo, R.;  Villagra, P.;  Alvarez, J. A.;  Pometti, C.;  Vilardi, J. C.
收藏  |  浏览/下载：6/0  |  提交时间：2019/11/27
Breeding population  Genetic variability  Local adaptation  Microsatellites  Seed sources  Provenance differentiation, Restoration  
Provenance and Drainage Evolution of the Red River Revealed by Pb Isotopic Analysis of Detrital K-Feldspar 期刊论文
GEOPHYSICAL RESEARCH LETTERS, 2019, 46 (12) : 6415-6424
作者:  Wang, Ce;  Liang, Xinquan;  Foster, David A.;  Liang, Xirong;  Zhang, Le;  Su, Ming
收藏  |  浏览/下载：7/0  |  提交时间：2019/11/26
provenance  detrital K-feldspar  Pb isotope  drainage evolution  Red River  East Asia  
Evidence for population differentiation among Jeffrey and Ponderosa pines in survival, growth and phenology 期刊论文
FOREST ECOLOGY AND MANAGEMENT, 2019, 434: 40-48
作者:  Martinez-Berdeja, Alejandra;  Hamilton, Jill A.;  Bontemps, Aurore;  Schmitt, Johanna;  Wright, Jessica W.
收藏  |  浏览/下载：5/0  |  提交时间：2019/04/09
Ponderosa pine  Jeffrey pine  Pinus jeffreyi  Pinus ponderosa  Provenance test  Climate change  Phenology  Survival  Growth  Local adaptation  Adaptational lag  
Dust Sources of Last Glacial Chinese Loess Based on the Iron Mineralogy of Fractionated Source Samples 期刊论文
GEOPHYSICAL RESEARCH LETTERS, 2019, 46 (4) : 2103-2110
作者:  Jia, Jia;  Wang, Youjun;  Xia, Dunsheng;  Lu, Hao;  Gao, Fuyuan
收藏  |  浏览/下载：7/0  |  提交时间：2019/04/09
Chinese Loess Plateau loess  provenance  iron mineralogy  particle-size-dependence  Tibet Plateau  Central Asian Orogenic Belt  
Survival, growth and cold hardiness tradeoffs in white spruce populations: Implications for assisted migration 期刊论文
FOREST ECOLOGY AND MANAGEMENT, 2019, 433: 544-552
作者:  Sebastian-Azcona, Jaime;  Hamann, Andreas;  Hacke, Uwe G.;  Rweyongeza, Deogratias
收藏  |  浏览/下载：10/0  |  提交时间：2019/04/09
Cold hardiness  Hardiness zones  Provenance trial  Climate change  Assisted migration