NDVI remote sensing

Knowledge graph centered on NDVI remote sensing with 73 nodes and 174 connections. Top connected: Rocky Mountain Biological Laboratory, Gothic, Two-form Bumble Bee, Bumble Bees, Yellow-fronted Bumble Bee.

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 14 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 (14)

Species Studied With This Protocol

Places Where Used