Estimating the Global Distribution of Field Size using Crowdsourcing

15558 32 85997 2 243882 document 85997 gcb.14492.pdf application/pdf d21ee90341b7750e5c37297f8785f0b4 MD5 2944536 2018-12-17 07:13:43 https://pure.iiasa.ac.at/id/eprint/15558/1/gcb.14492.pdf 15558 1 1 application/pdf text en public cc_by_nc_4

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published 86003 2 243896 document 86003 lightbox.jpg image/png c3572bc5502f95eae940a45bc95454f6 MD5 57982 2018-12-17 07:24:03 https://pure.iiasa.ac.at/id/eprint/15558/2/lightbox.jpg 15558 2 2 image/png other Thumbnails conversion from text to thumbnail_lightbox en public

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http://eprints.org/relation/isVersionOf https://pure.iiasa.ac.at/id/document/85997 http://eprints.org/relation/isVolatileVersionOf https://pure.iiasa.ac.at/id/document/85997 http://eprints.org/relation/isIndexCodesVersionOf https://pure.iiasa.ac.at/id/document/85997 archive 353 disk0/00/01/55/58 2018-11-22 09:51:12 2025-03-12 05:00:27 2018-11-22 09:51:12 article show 1 Lesiv M. 8477 0000-0001-9846-3342 Laso Bayas J.C. 2106 0000-0003-2844-3842 See L. 8571 0000-0002-2665-7065 Dürauer M. 2013 Dahlia D. Durando N. Hazarika R. Sahariah P.K. Vakolyuk M. Blyshchyk V. 8814 Bilous A. Perez-Hoyos A. Gengler S. Prestele R. Bilous S. Akhtar I.H. Singha K. Choudhury S.B. Chetri T. Malek Z. Bungnamei K. Saikia A. Sahariah D. Narzary W. Danylo O. 8670 Sturn T. 2051 Karner M. 1983 McCallum I. 1731 0000-0002-5812-9988 Schepaschenko D. 7435 0000-0002-7814-4990 Moltchanova E. 7915 Fraisl D. 2123 0000-0001-7523-7967 Moorthy I. 2089 0000-0002-3664-3855 Fritz S. 8130 0000-0003-0420-8549 Estimating the Global Distribution of Field Size using Crowdsourcing pub prog_esm field size, crowdsourcing, visual interpretation, environmental changes, food security, Geo-Wiki There is increasing evidence that smallholder farms contribute substantially to food production globally yet spatially explicit data on agricultural field sizes are currently lacking. Automated field size delineation using remote sensing or the estimation of average farm size at subnational level using census data are two approaches that have been used. However, both have limitations, e.g. automatic field size delineation using remote sensing has not yet been implemented at a global scale while the spatial resolution is very coarse when using census data. This paper demonstrates a unique approach to quantifying and mapping agricultural field size globally using crowdsourcing. A campaign was run in June 2017 where participants were asked to visually interpret very high resolution satellite imagery from Google Maps and Bing using the Geo-Wiki application. During the campaign, participants collected field size data for 130K unique locations around the globe. Using this sample, we have produced the most accurate global field size map to date and estimated the percentage of different field sizes, ranging from very small to very large, in agricultural areas at global, continental and national levels. The results show that smallholder farms occupy up to 40% of agricultural areas globally, which means that, potentially, there are many more smallholder farms in comparison with the two different current global estimates of 12% and 24%. The global field size map and the crowdsourced data set are openly available and can be used for integrated assessment modelling, comparative studies of agricultural dynamics across different contexts, for training and validation of remote sensing field size delineation, and potential contributions to the Sustainable Development Goal of Ending hunger, achieve food security and improved nutrition and promote sustainable agriculture. 2019-01 published Wiley-Blackwell 10.1111/gcb.14492 181 172 276 73 1159 59 301 144 202 279 1460 2612 211 98 public Global Change Biology 25 1 174-186 TRUE 1365-2486 https://pure.iiasa.ac.at/id/eprint/15526/ data Stimulating Innovation for Global Monitoring of Agriculture and its Impact on the Environment in support of GEOGLAM (SIGMA, FP7 603719) Harnessing the power of crowdsourcing to improve land cover and land-use information (CROWDLAND, FP7 617754) Geo-Wiki FALSE yes info:eu-repo/grantAgreement/EC/FP7/617754/EU//CROWDLAND; info:eu-repo/grantAgreement/EC/FP7/603719/EU//SIGMA; info:eu-repo/semantics/article info:eu-repo/semantics/embargoedAccess