The correlation between various indices to find growing crop conditions using multispectral remote sensing techniques
Student name: Ms Anjali Kumari
Guide: Dr Chander Kumar Singh
Year of completion: 2017
Host Organisation: Climate Connect Knowledge Solution Pvt. Ltd., New Delhi
Supervisor (Host Organisation): Mr Ravi Sinha
Abstract: Detection of Crop health is crucial for productive crop management. Satellite
monitoring is important to find vegetation health. Crop phená´lá´gy is adversely
affected by environmental conditions. Timely and accurate crop health alert can
decrease the probability á´f cold damage and safe millions of rupees which directly
affects the economy of the country. Remote sensing has the potential to identify the
crops affected by environmental conditions such as too dry or wet, hot or cold.
Images can be obtained during the harvesting period to detect problems and to
monitor the effect of the treatment.
Vegetation indices are commonly used in unsupervising phenology stages
throughout the harvesting period. The most commonly used indices are normalized
difference vegetation index which is used to calculate chlorophyll content in the
crop. NDVI utilizes differences in reflectance between visible and infrared spectra tá´
expedite remá´te á´bservatiá´n á´f vegetatiá´n due tá´ specific leaf characteristics at a
cellular level and the internal water status. The aim of this paper was to identify the
crop health condition using LANDSAT 8 satellite imagery and ground truth (GPS)
dataset. Grondtruth dataset is validated with the satellite imagery and statistical
relationship between NDVI and NDWI is calculated to find the health of the crop.
Unsupervised classification is done to differentiate between useful crop and other
vegetation.
The reduction in chlorophyll content indicates the reduction in nitrogen level in crop
which directly affect health of the crop. So it is required to find the relationship
between two important vegetation indices i.e. NDVI which is used to find
chlorophyll content in the crop and NDWI which is use to find water stress in the
crop. The result shows that NDVI is negatively correlated with NDWI, this shows
that when chlorophyll content in crop increases water stress decreases.
Key Words: Vegetation Indices, NDVI, NAVI, NDWI, NDII, SR, Classification.
