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Future changes in the trading of virtual water 期刊论文
NATURE COMMUNICATIONS, 2020, 11 (1)
作者:  Graham, Neal T.;  Hejazi, Mohamad, I;  Kim, Son H.;  Davies, Evan G. R.;  Edmonds, James A.;  Miralles-Wilhelm, Fernando
收藏  |  浏览/下载:15/0  |  提交时间:2020/08/09
Abrupt increase in harvested forest area over Europe after 2015 期刊论文
NATURE, 2020, 583 (7814) : 72-+
作者:  Guido Ceccherini;  Gregory Duveiller;  Giacomo Grassi;  Guido Lemoine;  Valerio Avitabile;  Roberto Pilli;  Alessandro Cescatti
收藏  |  浏览/下载:19/0  |  提交时间:2020/07/06

Fine-scale satellite data are used to quantify forest harvest rates in 26 European countries, finding an increase in harvested forest area of 49% and an increase in biomass loss of 69% between 2011-2015 and 2016-2018.


Forests provide a series of ecosystem services that are crucial to our society. In the European Union (EU), forests account for approximately 38% of the total land surface(1). These forests are important carbon sinks, and their conservation efforts are vital for the EU'  s vision of achieving climate neutrality by 2050(2). However, the increasing demand for forest services and products, driven by the bioeconomy, poses challenges for sustainable forest management. Here we use fine-scale satellite data to observe an increase in the harvested forest area (49 per cent) and an increase in biomass loss (69 per cent) over Europe for the period of 2016-2018 relative to 2011-2015, with large losses occurring on the Iberian Peninsula and in the Nordic and Baltic countries. Satellite imagery further reveals that the average patch size of harvested area increased by 34 per cent across Europe, with potential effects on biodiversity, soil erosion and water regulation. The increase in the rate of forest harvest is the result of the recent expansion of wood markets, as suggested by econometric indicators on forestry, wood-based bioenergy and international trade. If such a high rate of forest harvest continues, the post-2020 EU vision of forest-based climate mitigation may be hampered, and the additional carbon losses from forests would require extra emission reductions in other sectors in order to reach climate neutrality by 2050(3).


  
Coronavirus vaccines: key questions 期刊论文
NATURE, 2020, 579 (7800) : 481-481
作者:  Esposito, Elga;  Li, Wenlu;  T. Mandeville, Emiri;  Park, Ji-Hyun;  Sencan, Ikbal;  Guo, Shuzhen;  Shi, Jingfei;  Lan, Jing;  Lee, Janice;  Hayakawa, Kazuhide;  Sakadzic, Sava;  Ji, Xunming;  Lo, Eng H.
收藏  |  浏览/下载:11/0  |  提交时间:2020/07/03

Some experts warn that accelerated testing will involve some risky trade-offs.


Some experts warn that accelerated testing will involve some risky trade-offs.


  
Vertebrates on the brink as indicators of biological annihilation and the sixth mass extinction 期刊论文
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 2020, 117 (24) : 13596-13602
作者:  Ceballos, Gerardo;  Ehrlich, Paul R.;  Raven, Peter H.
收藏  |  浏览/下载:9/0  |  提交时间:2020/06/09
endangered species  sixth mass extinction  population extinctions  conservation  ecosystem services  
Fire mosaics and habitat choice in nomadic foragers 期刊论文
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 2020, 117 (23) : 12904-12914
作者:  Bird, Rebecca Bliege;  McGuire, Chloe;  Bird, Douglas W.;  Price, Michael H.;  Zeanah, David;  Nimmo, Dale G.
收藏  |  浏览/下载:12/0  |  提交时间:2020/06/01
ideal free distribution  positive density dependence  niche construction  historical ecology  hunter-gatherer mobility  
The vertical structure and spatial variability of lower-tropospheric water vapor and clouds in the trades 期刊论文
ATMOSPHERIC CHEMISTRY AND PHYSICS, 2020, 20 (10) : 6129-6145
作者:  Naumann, Ann Kristin;  Kiemle, Christoph
收藏  |  浏览/下载:5/0  |  提交时间:2020/06/01
A trait-based understanding of wood decomposition by fungi 期刊论文
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 2020, 117 (21) : 11551-11558
作者:  Lustenhouwer, Nicky;  Maynard, Daniel S.;  Bradford, Mark A.;  Lindner, Daniel L.;  Oberle, Brad;  Zanne, Amy E.;  Crowther, Thomas W.
收藏  |  浏览/下载:16/0  |  提交时间:2020/05/20
fungal traits  wood decomposition  carbon cycle  functional biogeography  decay rate  
Dynamics in a simple evolutionary-epidemiological model for the evolution of an initial asymptomatic infection stage 期刊论文
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 2020, 117 (21) : 11541-11550
作者:  Saad-Roy, Chadi M.;  Wingreen, Ned S.;  Levin, Simon A.;  Grenfell, Bryan T.
收藏  |  浏览/下载:9/0  |  提交时间:2020/05/13
evolutionary analysis  pathogen life history strategies  asymptomatic infection stage  
Internal state dynamics shape brainwide activity and foraging behaviour 期刊论文
NATURE, 2020, 577 (7789) : 239-+
作者:  Marques, Joao C.;  Li, Meng;  Schaak, Diane;  Robson, Drew N.;  Li, Jennifer M.
收藏  |  浏览/下载:5/0  |  提交时间:2020/07/03

The brain has persistent internal states that can modulate every aspect of an animal'  s mental experience(1-4). In complex tasks such as foraging, the internal state is dynamic(5-8). Caenorhabditis elegans alternate between local search and global dispersal(5). Rodents and primates exhibit trade-offs between exploitation and exploration(6,7). However, fundamental questions remain about how persistent states are maintained in the brain, which upstream networks drive state transitions and how state-encoding neurons exert neuromodulatory effects on sensory perception and decision-making to govern appropriate behaviour. Here, using tracking microscopy to monitor whole-brain neuronal activity at cellular resolution in freely moving zebrafish larvae(9), we show that zebrafish spontaneously alternate between two persistent internal states during foraging for live prey (Paramecia). In the exploitation state, the animal inhibits locomotion and promotes hunting, generating small, localized trajectories. In the exploration state, the animal promotes locomotion and suppresses hunting, generating long-ranging trajectories that enhance spatial dispersion. We uncover a dorsal raphe subpopulation with persistent activity that robustly encodes the exploitation state. The exploitation-state-encoding neurons, together with a multimodal trigger network that is associated with state transitions, form a stochastically activated nonlinear dynamical system. The activity of this oscillatory network correlates with a global retuning of sensorimotor transformations during foraging that leads to marked changes in both the motivation to hunt for prey and the accuracy of motor sequences during hunting. This work reveals an important hidden variable that shapes the temporal structure of motivation and decision-making.


  
DNA metabarcoding reveals metacommunity dynamics in a threatened boreal wetland wilderness 期刊论文
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 2020, 117 (15) : 8539-8545
作者:  Bush, Alex;  Monk, Wendy A.;  Compson, Zacchaeus G.;  Peters, Daniel L.;  Porter, Teresita M.;  Shokralla, Shadi;  Wright, Michael T. G.;  Hajibabaei, Mehrdad;  Baird, Donald J.
收藏  |  浏览/下载:16/0  |  提交时间:2020/05/13
occupancy  detectability  taxonomic resolution  stochasticity  power analysis