January 11, 2020
Chief Science Officer
Vegetable sellers near Kikuyu, Kenya. Photo taken by the author.Most agricultural regions are rural, remote and are less well connected to the digital economy. Anyone who has driven past vast expanses of wheat or watermelon fields wonders – how is the crop doing this year? Are those yellow plants nearby going to affect the crop? Are other fields in this area suffering? How does the farmer know when something is going amiss, given the enormous extent, remoteness and diversity of agricultural fields? Will I be able to find tomatoes when they are ready for harvest, or will they be expensive and of poor quality?
What is Remote Sensing and Why It Matters
Satellite remote sensing of agricultural regions can be used to answer these questions for both the grower and the consumer. Remote sensing is the use of digital environmental sensors mounted on aircraft or on satellites to detect and monitor reflections of sunlight off of the Earth. Remote measurement of canopy greenness is one of the most widely used kinds of satellite remote sensing and can be used to compare the health of a field remotely. Vegetation greenness is a measure of how many actively photosynthesizing leaves and plants are in a field, which can be used together with historical yield from that crop to estimate how well the current field is doing compared to previous seasons and other fields growing the same crop. The data can show when the plants emerge from the ground, when they are at their most tall and vigorous, and when they are ready to harvest.
Uses for Remote Sensing
Satellite remote sensing imagery are also able to identify regions, fields and even small areas within fields that are performing poorly. This poor field performance can be caused by lack of rainfall, inadequate fertilization, temperatures that are too cold or too hot, or because the crop or variety is poorly suited to the region. Because the data is comparable across fields and is acquired every third day for the entire world, remote observations are an invaluable tool to determine overall crop health in a specific field or a farm. To do this well, however, scientists need high quality information about the crop to diagnose the problem.
Remote Sensing’s Challenge
Continuously updated, field-specific information on crop management has never been available from large numbers of growers. This has restricted the use of satellite remote sensing to estimates of canopy health that cannot be further interpreted. Transforming satellite data into information that can be used by farmers to respond to minute changes in their crop in a precise way is a goal long held by the remote sensing community.
6th Grain and Remote Sensing
As mobile phones and high-speed networks become integrated into rural areas, growers will begin to use them to record their field information in structured ways that can be combined with satellite data in new ways. 6th Grain is working to develop easy-to-use, intuitive mobile tools that will allow a farmer to create a digital outline of their field and keep records on their phone. By tracking each activity and purchase, the grower will be able to compare different management approaches and their investment in seeds and chemicals to measure their profitability. There is an enormous need to better understand what works and what does not. Keeping high quality records is the best way for a grower to meet this need. These records can also be used to transform remotely sensed data into powerful tools to improve crop management and respond to problems promptly.
Improving the usefulness of satellite remote sensing will benefit the grower and will allow the consumer to finally find the perfect tomato.