Introduction

The agricultural sector in Zimbabwe continues to be important, and remote sensing has been used to help it.

Introduction

Remote sensing is a technology that uses the electromagnetic spectrum to collect data about Earth’s surface, atmosphere and oceans. It can provide information on the state of the environment and its resources, which can be used to detect changes in vegetation, weather systems, geological formations and other natural processes.

Just as a doctor who has never seen you before needs to use an x-ray machine or CT scan (which is like a very detailed photo) to look inside your body; remote sensing instruments gather information on what makes up Earth’s surface by measuring radiation emitted from various parts of it. This ‘radiation’ includes visible light plus infrared radiation (heat), microwave radiation (radio waves), ultraviolet light and gamma rays.

Applications

The following are some common applications of remote sensing in agriculture:

• Crop yield estimation
• Soil moisture monitoring/prediction
• Monitoring of plant health and stress (nutrient deficiency, drought, pest attack etc)
• Determination of phenotypic behavior by combining spectral data with other data such as soil pH measurements, water-holding capacity measurements or field observations

Satellite Image Classification of Crops

Remotely sensed data can be used to monitor crop health and growth. It is also possible to classify crops using remote sensing.

Challenges in the Application of Remote Sensing to Agriculture in Zimbabwe

There are a number of challenges that have to be overcome before remote sensing can be effectively applied to agriculture in Zimbabwe. As stated above, most of these challenges are related to capacity development and resource availability.

Resources such as equipment and software (see below) need to be made available at affordable prices for researchers, practitioners and end users alike. Furthermore, there is a need for training programmes on the application of remote sensing technologies in order

to give farmers an opportunity to learn how they can use this technology themselves instead of always relying on experts or research institutions that possess such equipment but lack experience with actual field application scenarios themselves.

The agricultural sector in Zimbabwe continues to be important, and remote sensing has been used to help it.

The agricultural sector in Zimbabwe continues to be important, and remote sensing has been used to help it. As one example, satellite imagery has been used to map crop yield and crop health. The MODIS (Moderate Resolution Imaging Spectroradiometer) sensors on board NASA’s Aqua and Terra satellites are capable of detecting plant stress due to water deficiency or heat stress by measuring the infrared reflectance of plants. Sentinel-2A data are also being used for monitoring crop conditions such as drought and diseases through spectral analyses using NDVI (Normalized Difference Vegetation Index).

Radar imagery can be another effective tool for characterizing crops from space because its high resolution allows better discrimination between different types of vegetation than optical or thermal sensors (such as MODIS or Landsat), particularly when clouds are present.

Conclusion

The agricultural sector continues to be important in Zimbabwe, and remote sensing has been used to help it. This research revealed that the main challenges facing the application of remote sensing in agriculture are low quality of images, lack of knowledge on how to use remote sensing data, and lack of training programs.