Crop Bioparameters
Satellite Data : Sentinel-2 (Multispectral) , Pixxel (Hyperspectral).
The Crop Biophysical and Biochemical Parameters model is a sophisticated tool employed in agricultural remote sensing to assess crucial physical and chemical attributes of crops. Among these attributes, the model primarily focuses on estimating key parameters such as Leaf Area Index (LAI), Chlorophyll content which are vital indicators of crop health, vigor, and physiological status. Apart from these two the models also estimates other parameters as Brown Pigments, Water Thickness, Carotenoids and Dry Weight. The model supports multispectral and hyperspectral images from the satellites (Sentinel 2 as well as Pixxel’s ) to estimate the crop parameters.
Use Case Example:
Input:
The Model requires a valid Area of Interest containing agricultural land.
Output:
Here, we can see the estimated LAI (Leaf Area Index) parameter along with statistics, including area and percentage across the range of values.
The model provides the following parameters which can be chosen from the dropdown:
- Leaf Area Index (LAI): LAI is defined as the total one-sided area of leaves (m²) per unit ground area (m²). LAI is a unitless quantity which generally varies between 0 to 8 values. Higher LAI values indicate a denser canopy with more leaves intercepting and absorbing light.
- Chlorophyll (Cab): Chlorophyll is a green pigment present in chloroplasts of plant cells, responsible for photosynthesis. Cab represents the concentration of chlorophyll in the leaves. Higher Cab values indicate a higher density of healthy green leaves, leading to increased absorption of red and blue light and reduced reflectance in these regions.
- Brown Pigments (Cbrown): Cbrown represents the concentration of brown pigments (e.g., tannins) in the leaves. Brown pigments are often associated with leaf senescence or stress. An increase in Cbrown leads to a decrease in the greenness of the vegetation, affecting the spectral response towards the electromagnetic spectrum.
- Dry Weight (DW): Dry Weight represents the dry biomass of leaves per unit leaf area (g/m²), excluding water content. It influences the reflectance in the shortwave infrared region as it relates to structural and biochemical properties of leaves. This parameter is crucial for estimating plant health and productivity.
- Equivalent Water Thickness (WT): EWT quantifies the amount of water in leaves per unit leaf area (cm). It significantly impacts absorption features in the near-infrared and shortwave infrared regions, making it a key parameter for assessing vegetation water status and drought conditions.
- Carotenoid Content (Car): Carotenoid Content measures the concentration of carotenoids (µg/cm²), which are pigments involved in photosynthesis and photoprotection. It affects reflectance in the visible spectrum, particularly in the blue-green region, and provides insights into plant stress and physiological state.
| Parameter | Most affecting wavelengths | Unit | Minimum Value | Maximum Value |
|---|---|---|---|---|
| Leaf Area Index ( LAI ) | 400 - 2500 nm | - | 0 | 8 |
| Chlorophyll Content ( Cab) | 450 - 600 nm | ug/cm2 | 0 | 60 |
| Brown Pigments ( Cbrown) | 450 - 600 nm | - | 0 | 1 |
| Dry Weight | 700 - 2500 nm | g/cm2 | 0 | 1 |
| Equivalent Water Thickness | 800 - 2500 nm | cm | 0 | 0.02 |
| Carotenoid Content | 450 - 550 nm | ug/cm2 | 0 | 25 |
Raster output is available to visualize on user interface and to download as a GeoTiff file for each parameter. Raster represents the attribute values for each pixel, different colors represent different value ranges associated to the color scale
Wavelength Table [Available to download as CSV]: This table will be available in case of Hyperspectral Images. The table provide information on the availability of bands in the image which are required to estimate a particular parameter:
- Leaf Area Index
- Chlorophyll Content
- Brown Pigments
| Parameter | Most affecting wavelengths | Unit | Minimum Value | Maximum Value | Support for Hyperspectral Images from Pixxel Sattelites |
|---|---|---|---|---|---|
| Leaf Area Index ( LAI ) | 400 - 2500 nm | - | 0 | 8 | Yes |
| Chlorophyll Content ( Cab) | 450 - 600 nm | ug/cm2 | 0 | 60 | Yes |
| Brown Pigments ( Cbrown) | 450 - 600 nm | - | 0 | 1 | Yes |
Following Parameters don’t have support for hyperspectral images, they only support Multispectral [Sentinel 2]
- Dry Weight
- Equivalent Water
- Thickness Carotenoid Content
Additional Details
Minimum size of Area of Interest required (in Sq KMs.): No limitations
Maximum size of Area of Interest supported (in Sq KMs.): 5000 sq KMs.
Geographies supported : All geographies are supported
Sensors Supported : Sentinel-2, Pixxel’s Sattelilite
Resolution of input imagery required as input to this model:
- Pixxel TD1 : 30m
- Sentinel-2 : 10m
Model Accuracy Range: Based on qualitative analysis, the accuracy comes out to be 80 to 85% (The model accuracy is dependent on the number of bands present in the imagery, the model has been observed to perform best on images containing more than 50 bands in the Visible Near Infrared region)
Important Note: The model currently only runs on pixels with NDVI values greater than 0.2 i.e. agriculture and forest lands.