I have recently written about agricultural data and its relationship to vertical farming technology. In the spring of 2016 I took my first graduate class on information visualization as I began my Masters in Data Science at Indiana University. I learned a lot in that class about how important it is to not only quantify information but to tell a story using visual cues. Today I want to take a closer look at some data visualizations of crop origins by Colin K. Khoury and his team at the International Center for Tropical Agriculture.
Looking at where crops are grown is important and quantifying this information is important to understanding the globalization of food systems and also has conservation and policy implications. Khoury and his team used open data from the FAO (Food and Agricultural Organization of the United Nations) to count crops contributing directly to human diets from 2009-2011. The data included 177 countries and covered 98.5% of the world’s population.
The CIAT study uses a map of the world with crops overlaid as shown in the feature image to tell the story of where certain crops originate. I think the use of icons to represent each crop helps improve the overall story. It’s clear from this graphic that North America and Northern Europe don’t have as many native crops as other regions of the world. North America has a diversity of blueberries, cranberries, grapes, pumpkins, raspberries, strawberries and sunflower. This data does not mean that only these crops are grown in North America. Rather, it means that these crops are important in and directly connected to the diets of other regions.
The study also uses circular plots (aka chord diagrams) to show the diversity of crops and the relationships between the regions. It measures the quantity of a particular crop by weight. Each region of the world is represented with a color for the crops grown natively or inside the country. The colors are connected to other regions around the world where those respective crops are part of the human diet. The width of each line indicates how much that crop contributes to the food supply in the connected region. You can see just one region of the world at a time by clicking on this interactive visualization. A summary graphic of the top crops in each region was added to the right of the circular plot.
Next week I want to look at the other data visualizations in this CIAT study that look at the production value of the crops of each region and discuss what questions this type of data raises and what issues it could address.