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Rapid growth of new atmospheric particles by nitric acid and ammonia condensation 期刊论文
NATURE, 2020, 581 (7807) : 184-+
作者:  Liang, Guanxiang;  Zhao, Chunyu;  Zhang, Huanjia;  Mattei, Lisa;  Sherrill-Mix, Scott;  Bittinger, Kyle;  Kessler, Lyanna R.;  Wu, Gary D.;  Baldassano, Robert N.;  DeRusso, Patricia;  Ford, Eileen;  Elovitz, Michal A.;  Kelly, Matthew S.;  Patel, Mohamed Z.;  Mazhani, Tiny;  Gerber, Jeffrey S.;  Kelly, Andrea;  Zemel, Babette S.;  Bushman, Frederic D.
收藏  |  浏览/下载:41/0  |  提交时间:2020/05/20

A list of authors and their affiliations appears at the end of the paper New-particle formation is a major contributor to urban smog(1,2), but how it occurs in cities is often puzzling(3). If the growth rates of urban particles are similar to those found in cleaner environments (1-10 nanometres per hour), then existing understanding suggests that new urban particles should be rapidly scavenged by the high concentration of pre-existing particles. Here we show, through experiments performed under atmospheric conditions in the CLOUD chamber at CERN, that below about +5 degrees Celsius, nitric acid and ammonia vapours can condense onto freshly nucleated particles as small as a few nanometres in diameter. Moreover, when it is cold enough (below -15 degrees Celsius), nitric acid and ammonia can nucleate directly through an acid-base stabilization mechanism to form ammonium nitrate particles. Given that these vapours are often one thousand times more abundant than sulfuric acid, the resulting particle growth rates can be extremely high, reaching well above 100 nanometres per hour. However, these high growth rates require the gas-particle ammonium nitrate system to be out of equilibrium in order to sustain gas-phase supersaturations. In view of the strong temperature dependence that we measure for the gas-phase supersaturations, we expect such transient conditions to occur in inhomogeneous urban settings, especially in wintertime, driven by vertical mixing and by strong local sources such as traffic. Even though rapid growth from nitric acid and ammonia condensation may last for only a few minutes, it is nonetheless fast enough to shepherd freshly nucleated particles through the smallest size range where they are most vulnerable to scavenging loss, thus greatly increasing their survival probability. We also expect nitric acid and ammonia nucleation and rapid growth to be important in the relatively clean and cold upper free troposphere, where ammonia can be convected from the continental boundary layer and nitric acid is abundant from electrical storms(4,5).


  
A 20-year tree liberation experiment in the Amazon: Highlights for diameter growth rates and species-specific management 期刊论文
FOREST ECOLOGY AND MANAGEMENT, 2019, 453
作者:  David, Hassan C.;  Carvalho, Joao O. P.;  Pires, Iran Paz;  Santos, Luana S.;  Barbosa, Eglison S.;  Braga, Nathalia S.
收藏  |  浏览/下载:18/0  |  提交时间:2020/02/17
Terra firme forest  Minimum cutting diameter  Cutting cycle  Individual-tree growth  Non-age-explicit growth model  
Inter-tree competitive processes during early growth of an experimental plantation of Eucalyptus pilularis in sub-tropical Australia 期刊论文
FOREST ECOLOGY AND MANAGEMENT, 2019, 451
作者:  West, P. W.;  Smith, R. G. B.
收藏  |  浏览/下载:18/0  |  提交时间:2019/11/27
Competition  Symmetric  Asymmetric  Diameter growth  Eucalyptus  Plantation  
The influence of different restoration thinning treatments on tree growth in a depleted forest system 期刊论文
FOREST ECOLOGY AND MANAGEMENT, 2019, 437: 10-16
作者:  Brown, Geoff W.;  Murphy, Andrew;  Fanson, Ben;  Tolsma, Am
收藏  |  浏览/下载:55/0  |  提交时间:2019/04/09
Diameter growth  Thinning intensity  Eucalyptus  Ecological thinning  Forestry  Silviculture  Box-Ironbark forest  
Management implications of tree growth patterns in miombo woodlands of Zambia 期刊论文
FOREST ECOLOGY AND MANAGEMENT, 2019, 436: 105-116
作者:  Chidumayo, E. N.
收藏  |  浏览/下载:18/0  |  提交时间:2019/04/09
Basal area  Diameter increment  Dry and wet miombo  Growth models  Permanent sample plots  Re-growth  
A stand table projection system for interior Douglas-fir in British Columbia, Canada 期刊论文
FOREST ECOLOGY AND MANAGEMENT, 2018, 409: 434-443
作者:  Jang, Woongsoon;  Eskelson, Bianca N. I.;  Marshall, Peter L.;  Moss, Ian
收藏  |  浏览/下载:18/0  |  提交时间:2019/04/09
Growth and yield  Diameter distribution model  Seemingly unrelated regression  Diameter growth equation  Prognosis(BC)  
Using tree-ring data to improve timber-yield projections for African wet tropical forest tree species 期刊论文
FOREST ECOLOGY AND MANAGEMENT, 2017, 400
作者:  Groenendijk, Peter;  Bongers, Frans;  Zuidema, Pieter A.
收藏  |  浏览/下载:22/0  |  提交时间:2019/04/09
Growth projections  Minimum logging diameter  Logging cycle  Future crop trees  Sustainable forest management  Timber volume  
Photoperiod cues and patterns of genetic variation limit phenological responses to climate change in warm parts of species' range: Modeling diameter-growth cessation in coast Douglas-fir 期刊论文
GLOBAL CHANGE BIOLOGY, 2017, 23 (8)
作者:  Ford, Kevin R.;  Harrington, Constance A.;  Clair, J. Bradley St.
收藏  |  浏览/下载:20/0  |  提交时间:2019/04/09
cambial growth  climate change  day length  diameter growth  genecology  phenology  Pseudotsuga menziesii var. menziesii  secondary growth  
Tree and stand recovery after heavy diameter-limit cutting in Norway spruce stands 期刊论文
FOREST ECOLOGY AND MANAGEMENT, 2017, 389
作者:  Valkonen, Sauli;  Lappalainen, Sanna;  Lande, Erkki;  Laiho, Olavi;  Saksa, Timo
收藏  |  浏览/下载:15/0  |  提交时间:2019/04/09
Diameter-limit cutting  Regeneration  Tree growth  Uneven-aged stands  Yield  
Twenty-five year response of non-crop trees to partial release during precommercial crop tree management 期刊论文
FOREST ECOLOGY AND MANAGEMENT, 2017, 387: 43817
作者:  Ward, Jeffrey S.
收藏  |  浏览/下载:16/0  |  提交时间:2019/04/09
Quercus  Acer  Betula  Partial release  Diameter growth  Upper canopy persistence