The Applications of Hyperspectral Imagery in Vegetation Stress

June 15, 2023
The Applications of Hyperspectral Imagery in Vegetation Stress

Hyperspectral imagery in agriculture has revolutionized the way Earth observation data is utilized in the sector. For years, remote sensing has played a crucial role in monitoring vegetation, managing agriculture, and predicting crop yields. However, traditional methods using RGB or multispectral sensors have limitations in providing a comprehensive understanding of the agricultural landscape.

Enter Pixxel's hyperspectral imaging satellite, a technology capable of capturing images across 250+ bands with a spatial resolution of 5 meters. This cutting-edge technology holds the potential to bring about a remarkable transformation in the monitoring, mitigation, and prevention of vegetation stress within the agriculture sector.

Ground zero: What causes vegetation stress?

Vegetation stress is any unfavorable condition or substance affecting or blocking a plant's  metabolism,  growth,  or  development.  Plant  and  vegetation  stress  varies  in severity  and  duration  and  can  be  induced  by  various  natural  and  anthropogenic factors.

Broadly, it can be classified into four groups:

•   Biotic - instigated by external living factors, such as bacteria, viruses, fungi, insects, and other plants

•   Abiotic - caused by non-living parts of the ecosystem, for example, extreme temperatures or severe winds

•   Physical - imposed by the physical environment including drought, water-logging and salinity

•   Chemical - caused by the state of the environment such as effects of air pollution, oil or gas spillage, pesticides, or soil pH

Several studies have shown the impacts of vegetation stress, including changes in growth  rates,  crop  yields,  water  absorption  patterns,  pH  levels  and  nutrition deficiencies. This means that early detection and diagnosis are fundamental for both prevention and cure. This is where hyperspectral imaging can be leveraged to its full potential.  

Hyperspectral Imaging

Hyperspectral images record the spectrum value for every pixel instead of just assigning primary colors, as is the case for RGB imagery. All objects or elements emit unique spectral signatures. Hyperspectral imaging sensors, equipped on satellites or other aerial platforms, use this spectral signature to identify these objects and, eventually, monitor changes in state or extent.

Each crop also has a known spectral value at every stage of development. Any variation from this value can be an early indicator of disease or stress long before any visible symptoms occur. Hyperspectral sensors capture these spectral signatures or values at a local or micro level to monitor any anomalies. What sets hyperspectral imaging apart is its unique capability to capture several chemical and biological traits within individual plant species by analyzing their reflective properties across a range of narrow spectral bands.

Besides the early detection of relevant factors and treatments, this technique can also be applied to understand the impact of an environment or locality on large-scale agriculture and inform future sowing strategies. The data can then be used to inform frequent interventions and enable a more sustainable decision-making process.

Applications of Hyperspectral Imaging across Agriculture

Hyperspectral imaging is well-equipped to identify, treat, and prevent vegetation stress across all four groups.

Hyperspectral imaging can also be used to identify the effects of abiotic stressors such as adverse wind, temperature, and water availability. While these factors are unavoidable, resulting from locality, environment, or climate change, the timely diagnosis allows for early intervention and therefore, mitigation of stress on the plant.

Chemical stress occurs due to toxic substances or a deficiency of nutrients. As each element has a spectral signature, this can be used to recognize, identify, and locate the source of harmful chemicals using hyperspectral sensors. Instances already exist where hyperspectral data was used to identify the presence of heavy metals and oil and gas leaks. Similarly, any physical stress brought on by phenomena including drought or waterlogging can be identified and dealt with efficiently and cost- effectively using hyperspectral imaging.

A new norm for agricultural purposes is emerging with the advent of hyperspectral imaging technology, as exemplified by Pixxel's advanced sensors. Overcoming initial barriers, hyperspectral imaging in agriculture is gaining traction and poised to revolutionize the industry. With Pixxel's cutting-edge technology, the adoption of hyperspectral imaging is becoming increasingly feasible, unlocking new possibilities and insights for the agricultural sector. Experience the power of hyperspectral imaging in agriculture with Pixxel's state-of-the-art sensors.