RT Journal Article
SR Electronic
T1 Global cropland connectivity: A risk factor for invasion and saturation by emerging pathogens and pests
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 106542
DO 10.1101/106542
A1 Y. Xing
A1 J. F. Hernandez Nopsa
A1 J. Andrade-Piedra
A1 F. Beed
A1 G. Blomme
A1 M. Carvajal Yepes
A1 D. L. Coyne
A1 G. A. Forbes
A1 J. Kreuze
A1 J. Kroschel
A1 P. L. Kumar
A1 J. P. Legg
A1 M. Parker
A1 E. Schulte-Geldermann
A1 K. A. Garrett
YR 2017
UL http://biorxiv.org/content/early/2017/02/10/106542.abstract
AB The geographic pattern of croplands is an important risk factor for the invasion of crop-specific pathogens and arthropods, and saturation by endemic pests. Understanding the structure of cropland networks supports sampling and mitigation strategies. We evaluated global networks of key vegetatively-propagated crops (banana, cassava, potato, sweetpotato, and yam) of particular importance to food security in the tropics. The risk of damage from diseases transmitted through vegetative propagation is a particular concern. We analyzed the structure of cropland networks for each crop, where the existence of a link between geographic location pairs was determined using a gravity model, as a function of the distance between the pair of locations and the product of the harvested crop area in the two locations. Networks were evaluated using a novel index of pathogen or arthropod invasion and saturation risk, based on the role of locations in bridging cropland areas and the degree of connectedness of a location and its neighbors. For example, in addition to locations with high risk due to high cropping density, locations with high risk because of their role as bridges for cassava include South-Central Nigeria, Central Ghana, and Southwestern Democratic Republic of Congo. For potato, bridges include Central and Southern Poland and Northern Ukraine. The highly-linked hub and bridge locations we identified are likely priorities for surveillance and management, and for tracing intra-region movement of pathogens and pests. Integrated analyses of invasion and saturation risk can simultaneously evaluate risk due to cropland connectivity along with other risk factors such as climate and trade routes.