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Inferring CO(2)fertilization effect based on global monitoring land-atmosphere exchange with a theoretical model 期刊论文
ENVIRONMENTAL RESEARCH LETTERS, 2020, 15 (8)
作者:  Ueyama, Masahito;  39;omi
收藏  |  浏览/下载:16/0  |  提交时间:2020/08/18
CO(2)fertilization effect  photosynthesis  evapotranspiration  eddy covariance  sun  shade model  
Mowing alters nitrogen effects on the community-level plant stoichiometry through shifting plant functional groups in a semi-arid grassland 期刊论文
ENVIRONMENTAL RESEARCH LETTERS, 2020, 15 (7)
作者:  Li, Shijie;  Wang, Fuwei;  Chen, Mengfei;  Liu, Zhengyi;  Zhou, Luyao;  Deng, Jun;  Dong, Changjun;  Bao, Guocheng;  Bai, Tongshuo;  Li, Zhen;  Guo, Hui;  Wang, Yi;  Qiu, Yunpeng;  Hu, Shuijin
收藏  |  浏览/下载:8/0  |  提交时间:2020/08/18
Nitrogen fertilization  mowing  plant stoichiometry  plant community structure  plant diversity  photosynthetic active radiation  gross ecosystem productivity  
Southern Ocean carbon sink enhanced by sea-ice feedbacks at the Antarctic Cold Reversal 期刊论文
NATURE GEOSCIENCE, 2020, 13 (7) : 489-+
作者:  Fogwill, C. J.;  Turney, C. S. M.;  Menviel, L.;  Baker, A.;  Weber, M. E.;  Ellis, B.;  Thomas, Z. A.;  Golledge, N. R.;  Etheridge, D.;  Rubino, M.;  Thornton, D. P.;  van Ommen, T. D.;  Moy, A. D.;  Curran, M. A. J.;  Davies, S.;  Bird, M., I;  Munksgaard, N. C.;  Rootes, C. M.;  Millman, H.;  Vohra, J.;  Rivera, A.;  Mackintosh, A.;  Pike, J.;  Hall, I. R.;  Bagshaw, E. A.;  Rainsley, E.;  Bronk-Ramsey, C.;  Montenari, M.;  Cage, A. G.;  Harris, M. R. P.;  Jones, R.;  Power, A.;  Love, J.;  Young, J.;  Weyrich, L. S.;  Cooper, A.
收藏  |  浏览/下载:14/0  |  提交时间:2020/06/29
A Model-Based Investigation of Terrestrial Plant Carbon Uptake Response to Four Radiation Modification Approaches 期刊论文
JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES, 2020, 125 (9)
作者:  Duan, Lei;  Cao, Long;  Bala, Govindasamy;  Caldeira, Ken
收藏  |  浏览/下载:9/0  |  提交时间:2020/07/02
Relaxation of Wind Stress Drives the Abrupt Onset of Biological Carbon Uptake in the Kerguelen Bloom: A Multisensor Approach 期刊论文
GEOPHYSICAL RESEARCH LETTERS, 2020, 47 (9)
作者:  Pellichero, Violaine;  Boutin, Jacqueline;  Claustre, Herve;  Merlivat, Liliane;  Sallee, Jean-baptiste;  Blain, Stephane
收藏  |  浏览/下载:6/0  |  提交时间:2020/07/02
onset of the phytoplankton bloom  mixing-layer depth  in situ high-resolution data  mixed-layer depth  air-sea heat flux  wind stress  
The fate of carbon in a mature forest under carbon dioxide enrichment 期刊论文
NATURE, 2020, 580 (7802) : 227-+
作者:  Sun, P. Z.;  Yang, Q.;  Kuang, W. J.;  Stebunov, Y. V.;  Xiong, W. Q.;  Yu, J.;  Nair, R. R.;  Katsnelson, M. I.;  Yuan, S. J.;  Grigorieva, I. V.;  Lozada-Hidalgo, M.;  Wang, F. C.;  Geim, A. K.
收藏  |  浏览/下载:70/0  |  提交时间:2020/05/13

Carbon dioxide enrichment of a mature forest resulted in the emission of the excess carbon back into the atmosphere via enhanced ecosystem respiration, suggesting that mature forests may be limited in their capacity to mitigate climate change.


Atmospheric carbon dioxide enrichment (eCO(2)) can enhance plant carbon uptake and growth(1-5), thereby providing an important negative feedback to climate change by slowing the rate of increase of the atmospheric CO2 concentration(6). Although evidence gathered from young aggrading forests has generally indicated a strong CO2 fertilization effect on biomass growth(3-5), it is unclear whether mature forests respond to eCO(2) in a similar way. In mature trees and forest stands(7-10), photosynthetic uptake has been found to increase under eCO(2) without any apparent accompanying growth response, leaving the fate of additional carbon fixed under eCO(2) unclear(4,5,7-11). Here using data from the first ecosystem-scale Free-Air CO2 Enrichment (FACE) experiment in a mature forest, we constructed a comprehensive ecosystem carbon budget to track the fate of carbon as the forest responded to four years of eCO(2) exposure. We show that, although the eCO(2) treatment of +150 parts per million (+38 per cent) above ambient levels induced a 12 per cent (+247 grams of carbon per square metre per year) increase in carbon uptake through gross primary production, this additional carbon uptake did not lead to increased carbon sequestration at the ecosystem level. Instead, the majority of the extra carbon was emitted back into the atmosphere via several respiratory fluxes, with increased soil respiration alone accounting for half of the total uptake surplus. Our results call into question the predominant thinking that the capacity of forests to act as carbon sinks will be generally enhanced under eCO(2), and challenge the efficacy of climate mitigation strategies that rely on ubiquitous CO2 fertilization as a driver of increased carbon sinks in global forests.


  
Tropical Rains Controlling Deposition of Saharan Dust Across the North Atlantic Ocean 期刊论文
GEOPHYSICAL RESEARCH LETTERS, 2020, 47 (5)
作者:  van der Does, Michelle;  Brummer, Geert-Jan A.;  van Crimpen, Fleur C. J.;  Korte, Laura F.;  Mahowald, Natalie M.;  Merkel, Ute;  Yu, Hongbin;  Zuidema, Paquita;  Stuut, JanBerend W.
收藏  |  浏览/下载:9/0  |  提交时间:2020/07/02
Asynchronous carbon sink saturation in African and Amazonian tropical forests 期刊论文
NATURE, 2020, 579 (7797) : 80-+
作者:  Wannes Hubau;  Simon L. Lewis;  Oliver L. Phillips;  Kofi Affum-Baffoe;  Hans Beeckman;  Aida Cuní;  -Sanchez;  Armandu K. Daniels;  Corneille E. N. Ewango;  Sophie Fauset;  Jacques M. Mukinzi;  Douglas Sheil;  Bonaventure Sonké;  Martin J. P. Sullivan;  Terry C. H. Sunderland;  Hermann Taedoumg;  Sean C. Thomas;  Lee J. T. White;  Katharine A. Abernethy;  Stephen Adu-Bredu;  Christian A. Amani;  Timothy R. Baker;  Lindsay F. Banin;  Fidè;  le Baya;  Serge K. Begne;  Amy C. Bennett;  Fabrice Benedet;  Robert Bitariho;  Yannick E. Bocko;  Pascal Boeckx;  Patrick Boundja;  Roel J. W. Brienen;  Terry Brncic;  Eric Chezeaux;  George B. Chuyong;  Connie J. Clark;  Murray Collins;  James A. Comiskey;  David A. Coomes;  Greta C. Dargie;  Thales de Haulleville;  Marie Noel Djuikouo Kamdem;  Jean-Louis Doucet;  Adriane Esquivel-Muelbert;  Ted R. Feldpausch;  Alusine Fofanah;  Ernest G. Foli;  Martin Gilpin;  Emanuel Gloor;  Christelle Gonmadje;  Sylvie Gourlet-Fleury;  Jefferson S. Hall;  Alan C. Hamilton;  David J. Harris;  Terese B. Hart;  Mireille B. N. Hockemba;  Annette Hladik;  Suspense A. Ifo;  Kathryn J. Jeffery;  Tommaso Jucker;  Emmanuel Kasongo Yakusu;  Elizabeth Kearsley;  David Kenfack;  Alexander Koch;  Miguel E. Leal;  Aurora Levesley;  Jeremy A. Lindsell;  Janvier Lisingo;  Gabriela Lopez-Gonzalez;  Jon C. Lovett;  Jean-Remy Makana;  Yadvinder Malhi;  Andrew R. Marshall;  Jim Martin;  Emanuel H. Martin;  Faustin M. Mbayu;  Vincent P. Medjibe;  Vianet Mihindou;  Edward T. A. Mitchard;  Sam Moore;  Pantaleo K. T. Munishi;  Natacha Nssi Bengone;  Lucas Ojo;  Fidè;  le Evouna Ondo;  Kelvin S.-H. Peh;  Georgia C. Pickavance;  Axel Dalberg Poulsen;  John R. Poulsen;  Lan Qie;  Jan Reitsma;  Francesco Rovero;  Michael D. Swaine;  Joey Talbot;  James Taplin;  David M. Taylor;  Duncan W. Thomas;  Benjamin Toirambe;  John Tshibamba Mukendi;  Darlington Tuagben;  Peter M. Umunay;  Geertje M. F. van der Heijden;  Hans Verbeeck;  Jason Vleminckx;  Simon Willcock;  Hannsjö;  rg Wö;  ll;  John T. Woods;  Lise Zemagho
收藏  |  浏览/下载:23/0  |  提交时间:2020/05/13

Structurally intact tropical forests sequestered about half of the global terrestrial carbon uptake over the 1990s and early 2000s, removing about 15 per cent of anthropogenic carbon dioxide emissions(1-3). Climate-driven vegetation models typically predict that this tropical forest '  carbon sink'  will continue for decades(4,5). Here we assess trends in the carbon sink using 244 structurally intact African tropical forests spanning 11 countries, compare them with 321 published plots from Amazonia and investigate the underlying drivers of the trends. The carbon sink in live aboveground biomass in intact African tropical forests has been stable for the three decades to 2015, at 0.66 tonnes of carbon per hectare per year (95 per cent confidence interval 0.53-0.79), in contrast to the long-term decline in Amazonian forests(6). Therefore the carbon sink responses of Earth'  s two largest expanses of tropical forest have diverged. The difference is largely driven by carbon losses from tree mortality, with no detectable multi-decadal trend in Africa and a long-term increase in Amazonia. Both continents show increasing tree growth, consistent with the expected net effect of rising atmospheric carbon dioxide and air temperature(7-9). Despite the past stability of the African carbon sink, our most intensively monitored plots suggest a post-2010 increase in carbon losses, delayed compared to Amazonia, indicating asynchronous carbon sink saturation on the two continents. A statistical model including carbon dioxide, temperature, drought and forest dynamics accounts for the observed trends and indicates a long-term future decline in the African sink, whereas the Amazonian sink continues to weaken rapidly. Overall, the uptake of carbon into Earth'  s intact tropical forests peaked in the 1990s. Given that the global terrestrial carbon sink is increasing in size, independent observations indicating greater recent carbon uptake into the Northern Hemisphere landmass(10) reinforce our conclusion that the intact tropical forest carbon sink has already peaked. This saturation and ongoing decline of the tropical forest carbon sink has consequences for policies intended to stabilize Earth'  s climate.


  
Parental-to-embryo switch of chromosome organization in early embryogenesis 期刊论文
NATURE, 2020: 142-+
作者:  Kim, Eugene;  Kerssemakers, Jacob;  Shaltiel, Indra A.;  Haering, Christian H.;  Dekker, Cees
收藏  |  浏览/下载:18/0  |  提交时间:2020/07/03

Single-cell allelic HiC analysis, combined with allelic gene expression and chromatin states, reveals parent-of-origin-specific dynamics of chromosome organization and gene expression during mouse preimplantation development.


Paternal and maternal epigenomes undergo marked changes after fertilization(1). Recent epigenomic studies have revealed the unusual chromatin landscapes that are present in oocytes, sperm and early preimplantation embryos, including atypical patterns of histone modifications(2-4) and differences in chromosome organization and accessibility, both in gametes(5-8) and after fertilization(5,8-10). However, these studies have led to very different conclusions: the global absence of local topological-associated domains (TADs) in gametes and their appearance in the embryo(8,9) versus the pre-existence of TADs and loops in the zygote(5,11). The questions of whether parental structures can be inherited in the newly formed embryo and how these structures might relate to allele-specific gene regulation remain open. Here we map genomic interactions for each parental genome (including the X chromosome), using an optimized single-cell high-throughput chromosome conformation capture (HiC) protocol(12,13), during preimplantation in the mouse. We integrate chromosome organization with allelic expression states and chromatin marks, and reveal that higher-order chromatin structure after fertilization coincides with an allele-specific enrichment of methylation of histone H3 at lysine 27. These early parental-specific domains correlate with gene repression and participate in parentally biased gene expression-including in recently described, transiently imprinted loci(14). We also find TADs that arise in a non-parental-specific manner during a second wave of genome assembly. These de novo domains are associated with active chromatin. Finally, we obtain insights into the relationship between TADs and gene expression by investigating structural changes to the paternal X chromosome before and during X chromosome inactivation in preimplantation female embryos(15). We find that TADs are lost as genes become silenced on the paternal X chromosome but linger in regions that escape X chromosome inactivation. These findings demonstrate the complex dynamics of three-dimensional genome organization and gene expression during early development.


  
Greenhouse gas implications of mobilizing agricultural biomass for energy: a reassessment of global potentials in 2050 under different food-system pathways 期刊论文
ENVIRONMENTAL RESEARCH LETTERS, 2020, 15 (3)
作者:  Kalt, Gerald;  Lauk, Christian;  Mayer, Andreas;  Theurl, Michaela C.;  Kaltenegger, Katrin;  Winiwarter, Wilfried;  Erb, Karl-Heinz;  Matej, Sarah;  Haberl, Helmut
收藏  |  浏览/下载:11/0  |  提交时间:2020/07/02
bioenergy  biomass potentials  energy scenario  GHG cost curve  agriculture  energy transition  natural climate solutions