NDVI remote sensing

Knowledge graph centered on NDVI remote sensing with 73 nodes and 157 connections. Top connected: Hummingbird, Bombus, Delphinium, Bombus terrestris, Bombus appositus.

Method synopsis

Time-lapse UAV surveys using RGB and multispectral cameras to monitor vegetation indices (NDVI, GCC) and plant height changes across a hillslope transect during growing seasons.

Synthesized from method descriptions across 9 papers using this protocol.

Procedure as described in the canonical source

Steps below were extracted from the paper that introduces this protocol — Advanced monitoring of soil-vegetation co-dynamics reveals the successive controls of snowmelt on soil moisture and on plant seasonal dynamics in a mountainous watershed (2023), Frontiers in Earth Science. Implementations in other papers (listed below) may differ.

1. Conduct UAV multispectral surveys
   UAV surveys were performed using a 3DR Solo platform equipped with a Sony α6000 digital camera for RGB imagery and a Micasense Rededge camera for multispectral data. Surveys covered a 300 x 500 m² area encompassing the study transect. About 50 small PVC targets were deployed as Ground Control Points (GCPs) for georeferencing. Flights were conducted at specific times during growing seasons.
   Quantities: 300 x 500 m² survey area, ~50 Ground Control Points, 4 flights in 2017, 4 flights in 2018Duration: 4 surveys per year in 2017 and 2018 during growing seasonsConditions: Growing season flights, clear weather conditions for optimal imagery
   Equipment: 3DR Solo UAV platform, Sony α6000 digital camera, Micasense Rededge camera, PVC targets for GCPs, Real Time Kinematic RTK-GPS
2. Process multispectral imagery and calculate vegetation indices
   RGB and multispectral imagery were georeferenced and reconstructed using AgiSoft software with structure-from-motion techniques. NDVI was calculated as (NIR-R)/(NIR+R) and GCC as [G/(R+G+B)]. Plant height changes were estimated by subtracting LiDAR DTM from UAV-derived Digital Surface Models (DSMs). Only datasets without cloud cover were used, limiting temporal analysis to specific dates.
   Quantities: 2-10cm pixel resolution for orthomosaics and DSMs, NDVI and GCC calculated across 200m side regionDuration: Post-processing after each UAV surveyConditions: Cloud-free conditions required for usable imagery
   AgiSoft reconstruction software, diffusive reflectance target for calibration

Typical Equipment

• 3DR Solo UAV platform
• Sony α6000 digital camera
• Micasense Rededge camera
• PVC targets for GCPs
• Real Time Kinematic RTK-GPS
• AgiSoft reconstruction software

Output Measurements

• NDVI
• GCC
• plant height
• orthomosaics
• digital surface models

Papers Using This Protocol (9)

Species Studied With This Protocol