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81.
Cohen J 《Science (New York, N.Y.)》2006,314(5800):743-745
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Robert R. Carlton Jon S. West Pete Smith Bruce D. L. Fitt 《European journal of plant pathology / European Foundation for Plant Pathology》2012,133(1):333-351
Crop disease not only threatens global food security by reducing crop production at a time of growing demand, but also contributes
to greenhouse gas (GHG) emissions by reducing efficiency of N fertiliser use and farm operations and by driving land use change.
GHG emissions associated with adoption of reduced tillage, organic and integrated systems of field crop production across
the UK and selected regions are compared with emissions from conventional arable farming to assess their potential for climate
change mitigation. The reduced tillage system demonstrated a modest (<20%) reduction in emissions in all cases, although in
practice it may not be suitable for all soils and it is likely to cause problems with control of diseases spread on crop debris.
There were substantial increases in GHG emissions associated with the organic and integrated systems at national level, principally
due to soil organic carbon losses from land use change. At a regional level the integrated system shows the potential to deliver
significant emission reductions. These results indicate that the conventional crop production system, coupled to reduced tillage
cultivation where appropriate, is generally the best for producing high yields to minimise greenhouse gas emissions and contribute
to global food security, although there may be scope for use of the integrated system on a regional basis. The control of
crop disease will continue to have an essential role in both maintaining productivity and decreasing GHG emissions. 相似文献
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J Cohen 《Science (New York, N.Y.)》2012,337(6091):176-177
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Wedeen VJ Rosene DL Wang R Dai G Mortazavi F Hagmann P Kaas JH Tseng WY 《Science (New York, N.Y.)》2012,335(6076):1628-1634
The structure of the brain as a product of morphogenesis is difficult to reconcile with the observed complexity of cerebral connectivity. We therefore analyzed relationships of adjacency and crossing between cerebral fiber pathways in four nonhuman primate species and in humans by using diffusion magnetic resonance imaging. The cerebral fiber pathways formed a rectilinear three-dimensional grid continuous with the three principal axes of development. Cortico-cortical pathways formed parallel sheets of interwoven paths in the longitudinal and medio-lateral axes, in which major pathways were local condensations. Cross-species homology was strong and showed emergence of complex gyral connectivity by continuous elaboration of this grid structure. This architecture naturally supports functional spatio-temporal coherence, developmental path-finding, and incremental rewiring with correlated adaptation of structure and function in cerebral plasticity and evolution. 相似文献