A Handheld Grassland Vegetation Monitoring System Based on Multispectral Imaging

Abstract

Monitoring grassland vegetation growth is of vital importance to scientific grazing and grassland management. People expect to be able to use a portable device, like a mobile phone, to monitor grassland vegetation growth at any time. In this paper, we propose a handheld grassland vegetation monitoring system to achieve the goal of monitoring grassland vegetation growth. The system includes two parts: the hardware unit is a hand-held multispectral imaging tool named ASQ-Discover based on a smartphone, which has six bands (wavelengths)—including three visible bands (450 nm, 550 nm, 650 nm), a red-edge band (750 nm), and two near-infrared bands (850 nm, 960 nm). The imagery data of each band has a size of 5120 × 3840 pixels with 8-bit depth. The software unit improves image quality through vignetting removal, radiometric calibration, and misalignment correction and estimates and analyzes spectral traits of grassland vegetation (Fresh Grass Ratio (FGR), NDVI, NDRE, BNDVI, GNDVI, OSAVI and TGI) that are indicators of vegetation growth in grassland. We introduce the hardware and software unit in detail, and we also experiment in five pastures located in Haiyan County, Qinghai Province. Our experimental results show that the handheld grassland vegetation growth monitoring system has the potential to revolutionize the grassland monitoring that operators can conduct when using a hand-held tool to achieve the tasks of grassland vegetation growth monitoring.

Characterising turf grass adaptation to drought and heat and assessing its potential cooling effect : Combined report on turf grass field experiments : Work package 1: Climate and drought, Work package 2: Climate and temperature

“…For our study, we used a combination of hyperspectral imaging techniques, soil sensor measurements, and gene expression analysis via RNA sequencing, to decipher the research questions. Hyperspectral imaging is an established method that is used to estimate plant biomass, structure, photosynthetic activity and biochemical properties (Hermanns et al 2021;Théau et al 2021;Zhang et al 2021), and therefore has potential use in our studies. Here, we defined drought resilience in the genotypes as monocultures and mixtures that maintain optimal growth during periods of water depravation and additionally, recover quickly from drought (and heat) stress after rainfall or irrigation (and lowering of temperature) occur.…”

Determination of Grass Quality Using Spectroscopy: Advances and Perspectives

“…It also requires a specialized laboratory, a demanding task that is not practical for people working in the field [5]. For this reason, technological alternatives are being considered that are capable of predicting grass properties without generating negative impacts on the environment, and that can be used to control the growth and development of grasses [6]. New calibration techniques and laboratory and remote sensing (RS) belonging to the spectroscopy can predict grasses components without chemical analysis [7].…”

Image Vignetting Correction Using a Deformable Radial Polynomial Model

“…Vignetting is usually unintentional and undesired. The appearance of this effect is particularly undesirable when there is a need for radiometric or quantitative image analysis, which is very common in different areas, e.g., astronomy [ 1 , 2 ]; microscopy [ 3 , 4 , 5 , 6 ]; and remote sensing applications using terrestrial [ 7 , 8 ], airborne [ 9 , 10 , 11 , 12 , 13 ] and spaceborne sensors [ 14 , 15 ], to name just a few of them. This phenomenon is also undesirable in the case of the use of computational imaging algorithms, such as the creation of high dynamic range (HDR) images [ 16 , 17 ], the stitching of static images to create panoramic [ 18 , 19 , 20 ] or mosaic images [ 3 , 4 , 5 , 6 , 21 ], as well as a panoramic real-time view [ 22 ].…”