Application of unmanned aerial systems was limited to the military until the last decade when we see dramatic growth of interest by civilian users. Among the many fields of application of unmanned ...

https://www.tandfonline.com/doi/pdf/10.1080/22797254.2018.1432993

Application of unmanned aerial vehicles in earth resources monitoring: Focus on evaluating potentials for forest monitoring in Ethiopia

Soybean aphid, Aphis glycines Matsumura (Hemiptera: Aphididae), is the most economically important insect pest of soybean in the north central United States. Scouting-based integrated pest management (IPM) programs could become more efficient and more widely adopted by using plant spectral reflectance to estimate soybean aphid injury. Our objective was to determine whether plant spectral reflectance is affected by soybean aphid feeding. Field trials were conducted in 2013 and 2014 using caged plots. Early-, late-, and noninfested treatments were established to create a gradient of soybean aphid pressure. Whole-plant soybean aphid densities were recorded weekly. Measurements of plant spectral reflectance occurred on two sample dates per year. Simple linear regression models were used to test the effect of cumulative aphid-days (CAD) on plant spectral reflectance at 680 nm (RED) and 800 nm (NIR), normalized difference vegetation index (NDVI), and relative chlorophyll content. Data indicated that CAD had no effect on canopy-level RED reflectance, but CAD decreased canopy-level NIR reflectance and NDVI. Canopy- and leaf-level measurements typically indicated similar plant spectral response to increasing CAD. CAD generally had no effect on relative chlorophyll content. The present study provides the first documentation that remote sensing holds potential for detecting changes in plant spectral reflectance induced by soybean aphid. The use of plant spectral reflectance in soybean aphid management may assist future IPM programs to reduce sampling costs and prevent prophylactic insecticide sprays.

https://bioone.org/journals/journal-of-economic-entomology/volume-108/issue-6/tov250/Soybean-Aphid-Hemiptera-Aphididae-Affects-Soybean-Spectral-Reflectance/10.1093/jee/tov250.pdf

Soybean Aphid (Hemiptera: Aphididae) Affects Soybean Spectral Reflectance

In this work, we discuss the radio propagation model of the UAVs when they act as mobile nodes belonging to a ground wireless sensor network. A typical application scenario is the agricultural field, where ground sensor nodes communicate with a flying node (the UAV). Currently, UAVs are attracting much attention both in the market and in the research field, thus more accurate radio propagation models are needed to properly estimate the effectiveness and the feasibility of the use of UAVs in several contexts. The main contribution of this work is in highlighting that the classical two-ray path loss model may be not enough accurate to take into account all the different factors that must be considered when using an UAV to communicate with and to control a ground Wireless Sensor Network.

http://ieeexplore.ieee.org/iel7/6971895/6984913/06984950.pdf

UAVs in WSNs for agricultural applications: An analysis of the two-ray radio propagation model

The Use of Unmanned Aerial Systems for Agriculture in Africa: Can It Fly?

This report provides a preliminary assessment of Unmanned Aerial Vehicle (UAV) technology for precision agriculture. It focuses on the macadamia industry, but an assessment is given of industry progress in other farming areas. Regardless of crop type, the principles of image capture and interpretation are the same, so insights gained elsewhere are highly relevant. Examples of geo-referenced imagery are provided, along with a photo-mosaic, to demonstrate the image processing steps before the aerial photography can be imported into a geographic information system (GIS) and used with other data layers to interpret management requirements or outcomes. A qualitative assessment of the strengths, weaknesses, opportunities and threats associated with the technology is given, as well as recommendations for its further development to meet horticultural needs

Adrian Van Boven

Papers

Linking UAV (unmanned aerial vehicle) technology with precision agriculture