The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
A multispectral imaging system is presented, using components that will support its deployment within the world of small-holder agriculture. An active narrowband illumination setup was selected, which allowed a low-cost broadband image sensor to be used. The preliminary set-up has been demonstrated with droughted tomato plants as a proof of concept. The results demonstrated a 5, 28 and 90% deterioration...
Various indices are used for assessing vegetation and soil properties in satellite remote sensing applications. Some indices, such as NDVI and NDWI, are defined based on the sensitivity and significance of specific bands. Nowadays, remote sensing capability with a good number of bands and high spatial resolution is available. Instead of classification based on indices, this paper explores direct classification...
Leaf area index (LAI) is an important parameter in the research of green vegetation ecosystem. Traditional methods for inversion of leaf area index based on hyperspectral image mainly use the reflectance of a band or an index generated by the combination of several bands, whose inversion accuracy is generally limited. In this paper, the BP (back-propagation) neural network is constructed to invert...
The primary objective of the SCMaP is to supply value added information about soils at three levels: 1) the spatial distribution of exposed soils; 2) temporal statistics of those soils; and, 3) a reflectance soil composite map. The SCMaP is designed for temperate climatic regions that comprise areas of extensive crop based agriculture where soils are commonly covered by vegetation. For the SCMaP satellite...
Leaf area index inversion using remote sensing is crucial for obtain vegetation information and monitoring global climate change. For the invalid uniform continuous canopy hypothesis of SAIL model, fractional canopy cover (FCC) is introduced and a simultaneous retrieval method of LAI and FCC is developed. SAIL model, PSO algorithm, and linear spectral mixture theory are combined in the novel method...
Mangrove forests provide a habitat for many endangered sea water-tolerant plant species and coastal fauna. Despite their ecological importance and shoreline protection properties, mangroves are under serious threat, resulting in significant losses in mangrove forest cover. Their efficient management requires frequent mapping to detect degradation or regeneration. The methodology presented in this...
AfriSAR is an ESA-funded airborne P- and L-band SAR campaign over the African tropical forests of Gabon carried out by ONERA (July 2015) and DLR (February 2016). The different acquisitions were designed in order to collect multibaseline fully polarimetric data allowing the inversion of key forest vertical structure-based parameters, like e.g. forest height and high resolution reflectivity profiles...
In this study, based on in-situ measurements collected in the North China Plain, adjusted vegetation water indexes were introduced on the basis of traditional vegetation water indexes to weak soil and background influence and propose multiscale winter wheat moisture inversion model that is suitable in North China Plain. The main conclusions are as follows: 1) The adjusted water indexes have a good...
This paper attempts to retrieve leaf water content (LWC) by developing new vegetation indices from the combination of the near-infrared (NIR) and middle-infrared (MIR) spectral reflectances. The expanded vegetation leaf model PROSPECT-VISIR and the widely validated four-stream scattering by arbitrarily inclined leaves (4SAIL) model are employed to simulate canopy reflectance in 0.4–5.7 μm region with...
The Sentinel-2A (S2A) Multi-Spectral Imager (MSI) is a new remote sensor launched on 23 June 2015 that provides unprecedented Earth observation with high spatial, spectral and temporal resolutions. It has high potential for chlorophyll content estimation. Chlorophyll content plays a crucial role in plant photosynthesis affecting the terrestrial carbon cycle. In this research, a physical retrieval...
High temporal and spactial resolution aerosol retrieval is a difficult task because of the absence of corresponding satellite data. Due to the lack of a shortwave infrared band near 2.1 um aboard on Gaofen-4 instrument, which is critical for determining surface reflectance. In this paper, a new algorithm resolving the problem based on Gaofen-4 that was placed in Geosynchronous (GEO) orbit and Landsat-8...
In this study, the Bottom-Of-Atmosphere (BOA) reflectance over Egbert, Ontario, Canada on September 24, 2016, as obtained by the Sentinel-2A Multi-Spectral Imager and corrected by the Sentinel-2 atmospheric Correction (Sen2Cor) software, was evaluated based on the 6SV atmospherically corrected reflectance. The aerosol and water vapor parameters used in the 6SV model were obtained from the AERONET...
A lot of spectral indices were developed based on the relationship between the spectral reflectance of the upper leaf surface and chlorophyll content. But the lower leaf surface may influence reflectance spectra because of canopy structure or the inclination of leaves. The results of this study showed that structural differences of the two leaf sides may result in differences in reflectance and spectral...
This contribution describes an ongoing effort, within the framework of the Copernicus Global Land Service 1, to develop an updated PROBA-V 300m NDVI product. Unlike previous versions of the PROBA-V NDVI at 300m, a normalisation for viewing and illumination geometry is performed and its temporal compositing strategy is aimed to maintain near real-timeness as possible. We use the MSG/SEVIRI NDVI angular...
Nowadays, deforestation activity still occurs despite having huge impact for human being. The different causes of deforestation are relatively brings different effect on nature, while forest fire and illegal logging are two major deforestation activities. In this paper, we proposed a new method to represent semantic analysis of deforestation effect based on its cause. We proposed idea to interpret...
Tanguar Haor undergoes a radical change in its form over the decades. This study illustrated that, about 40% land cover of the total study area has been converted. Forested and High land vegetation's are disappearing rapidly, deep water bodies consist of large lakes are becoming the rare feature of the study area. Widespread development of settlement and dominant shallow water feature are converting...
This study researched the estimation methods of nitrogen concentration of water hyacinth by hyperspectral remote sensing data. The spectral reflectance characteristics were analyzed based on field experiments consisting of different nitrogen levels in three growing seasons. This study investigated the bands and hyperspectral characteristics parameters sensitive to nitrogen concentration through correlative...
The robust and accurate retrieval of biophysical vegetation variables from remotely sensed data using radiative transfer models (RTMs) has been generally hampered by the ill-posed inverse problem. To alleviate this issue and improve the retrieval accuracy, a two-step inversion method based on the PROSAIL (PROSPECT+SAIL) radiative transfer model has been developed to consider the spectral information...
Remote sensing techniques applied in crop monitoring and management can help to reduce the input of nitrogen without reducing crop yield and accurately predict nitrogen demand [1]. The objective of this study is to use the ground based multispectral images to predict canopy nitrogen level for soybeans in southwestern Ontario. A light weight multispectral camera were used to collect multispectral measurements...
Hyperspectral measurements were carried out at tree canopy as well as leaf levels in an olive field around the Jebel Ressas mine site using the ASD (350 – 2500 nm) instrument. The main objective of this study was to explore hyperspectral reflectance spectroscopy to detect heavy metal vegetation stress as an indicator of soil contamination. Moreover, the used families of Vegetation Indices were optimized...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.