Andreas Hueni

Andreas Hueni
University of Zurich | UZH · Institut für Geographie

Dr. sc.nat.

About

126
Publications
40,143
Reads
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2,336
Citations
Citations since 2016
52 Research Items
1828 Citations
2016201720182019202020212022050100150200250300
2016201720182019202020212022050100150200250300
2016201720182019202020212022050100150200250300
2016201720182019202020212022050100150200250300

Publications

Publications (126)
Article
Full-text available
Remote sensing enhances large-scale biodiversity monitoring by overcoming temporal and spatial limitations of ground-based measurements and allows assessment of multiple plant traits simultaneously. The total set of traits and their variation over time is specific for each individual and can reveal information about the genetic composition of fores...
Conference Paper
Solar photovoltaic is a promising and growing resource for green energy generation. Detecting and monitoring the performance of photovoltaic modules is necessary. The use of remote sensing data has the potential to avoid labor- and time-consuming fieldwork. However, current research on PV detection mostly focuses on airborne and spaceborne color im...
Article
The upcoming Fluorescence Explorer (FLEX) satellite mission aims to provide high quality radiometric measurements for subsequent retrieval of sun-induced chlorophyll fluorescence (SIF). The combination of SIF with other observations stemming from the FLEX/Sentinel-3 tandem mission holds the potential to assess complex ecosystem processes. The calib...
Article
Full-text available
We present results from the Munich Nitrogen dioxide (NO2) Imaging Campaign (MuNIC), where NO2 near-surface concentrations (NSCs) and vertical column densities (VCDs) were measured with stationary, mobile, and airborne in situ and remote sensing instruments in Munich, Germany. The most intensive day of the campaign was 7 July 2016, when the NO2 VCD...
Conference Paper
Spectral libraries play a major role in imaging spectroscopy. They are commonly used to store end-member and spectrally pure material spectra, which are primarily used for mapping or unmixing purposes. However, the development of spectral libraries is time consuming and usually sensor and site dependent. Spectral libraries are therefore often devel...
Preprint
We present results from the Munich NO2 imaging campaign (MuNIC) where nitrogen dioxide (NO2) near-surface concentrations (NSC) and vertical column densities (VCD) were measured with stationary, mobile and airborne in situ and remote sensing instruments. The most intensive day of the campaign was 7 July 2016, when the NO2 VCD field was mapped with t...
Article
Full-text available
The measurement of leaf optical properties (LOP) using reflectance and scattering properties of light allows a continuous, time-resolved, and rapid characterization of many species traits including water status, chemical composition, and leaf structure. Variation in trait values expressed by individuals result from a combination of biological and e...
Article
Full-text available
Over the past decades, solar panels have been widely used to harvest solar energy owing to the decreased cost of silicon-based photovoltaic (PV) modules, and therefore it is essential to remotely map and monitor the presence of solar PV modules. Many studies have explored on PV module detection based on color aerial photography and manual photo int...
Article
Full-text available
1. Trait-based ecology holds the promise to explain how plant communities work, for example, how functional diversity may support community productivity. However, so far it has been difficult to combine field-based approaches assessing traits at the level of plant individuals with limited spatial coverage and approaches using remote sensing (RS) wi...
Conference Paper
The accurate characterisation of the instrumental spectral performance of field spectroradiometers acquires particular importance in view of the instruments' widespread use for calibrating and validating airborne- and satellite-based optical sensor systems. Typically, spectral calibration relies on the basic assumption of a Gaussian instrumental sp...
Article
A key characteristic of a spectroradiometer is the instrumental spectral response function (ISRF) that is determined during spectral characterization and calibration. The response shape of the ISRF is commonly assumed to be Gaussian, though this is known to not always be the best description. We show that in the context of laboratory calibration, t...
Preprint
Full-text available
The measurement of leaf optical properties (LOP) using reflectance and scattering properties of light allows a continuous, time-resolved, and rapid characterization of many species traits including water status, chemical composition, and leaf structure. Variation in trait values expressed by individuals result from a combination of biological and e...
Article
Full-text available
In rugged terrain, topography substantially influences the illumination and observation geometry, and thus, the bidirectional reflectance distribution function (BRDF) of a surface. While this problem has been known and investigated for spaceborne optical data since the 1980s, it has led to several well-known topographic correction methods. To date,...
Conference Paper
Hyperspectral target detection experiments under nonideal conditions are scarce. An extensive multi-scale and multi-temporal field experiment was designed towards the goal of knowledge expansion under such circumstances. A range of camouflage materials and specific targets of interest were placed in a realistic natural environment with vegetation c...
Conference Paper
Remote sensing has demonstrated its potential for widescale biodiversity monitoring. It overcomes the spatial limitations of ground-based measurements and allows acquiring high-temporal, -spatial and -spectral resolution data. The temporal trajectories of vegetation spectral responses hold information about time-specific physiological and morpholog...
Technical Report
Full-text available
"WG4 Instruments and Uncertainty Questionnaire: Results" presents the results of a questionnaire conducted in 2019 within the SENSECO COST action. But it is much more than that. This work starts off with a well-written description of the concept of uncertainty. Author Luc Sierro has well risen to the challenge of presenting the usually dry topic of...
Article
Full-text available
Spectral Information Systems provide a framework to assemble, curate, and serve spectral data and their associated metadata. This article documents the evolution of the SPECCHIO system, devised to enable long-term usability and data-sharing of field spectroradiometer data. The new capabilities include a modern, web-based client-server architecture,...
Article
Knowledge of the spatial distribution of tree species is important for efficiently managing and monitoring forested ecosystems, especially in mixed forests of the temperate zone. In this study, we fused imaging spec-troscopy (IS) data with leaf-on and off small-footprint airborne laser scanning (ALS) data, for tree species identification in a dense...
Article
The roles of quantitative remote sensing products in scientific research and quantitative applications lie in their ability to record the real states of earth surface features. Therefore, it is crucial to quantify the performance of remote sensing products. However, validation is not straightforward due to the scale effects caused by surface hetero...
Article
Full-text available
Hyperspectral remote sensing (RS) provides unique possibilities to monitor peatland vegetation traits and their temporal dynamics at a fine spatial scale. Peatlands provide a vital contribution to ecosystem services by their massive carbon storage and wide heterogeneity. However, monitoring, understanding, and disentangling the diverse vegetation t...
Article
Full-text available
Hyperspectral remote sensing (RS) provides unique possibilities to monitor peatland vegetation traits and their temporal dynamics at a fine spatial scale. Peatlands provide a vital contribution to ecosystem services by their massive carbon storage and wide heterogeneity. However, monitoring, understanding, and disentangling the diverse vegetation t...
Article
Full-text available
Growing interest in the proximal sensing of sun‐induced chlorophyll fluorescence (SIF) has been boosted by space-based retrievals and up-coming missions such as the FLuorescence EXplorer (FLEX). The European COST Action ES1309 “Innovative optical tools for proximal sensing of ecophysiological processes” (OPTIMISE, ES1309; https://optimise.dcs.aber....
Article
Full-text available
Imaging and non-imaging spectroscopy employed in the field and from aircraft is frequently used to assess biochemical, structural, and functional plant traits, as well as their dynamics in an environmental matrix. With the increasing availability of high-resolution spectroradiometers, it has become feasible to measure fine spectral features, such a...
Article
Imaging spectroscopy is frequently used to assess traits and functioning of vegetated ecosystems. Applied reflectance- and radiance-based approaches critically rely on accurate estimates of surface irradiance. Accurate retrievals of surface irradiance are, however, nontrivial and often error-prone, thus causing inaccurate estimates of vegetation in...
Article
Full-text available
This study assessed accuracies of MCD43A3, Global Land-Surface Satellite (GLASS) and forthcoming Multi-source Data Synergized Quantitative Remote Sensing Production system (MuSyQ) albedos using ground observations and Huan Jing (HJ) data over the Heihe River Basin. MCD43A3 and MuSyQ albedos show similar high accuracies with identical root mean squa...
Article
Due to the large carbon dioxide (CO2) fluxes between terrestrial ecosystems and the atmosphere, dynamics of photosynthesis can have significant effects on atmospheric CO2 concentrations and lead to large uncertainties in ecosystem C budgets. Remote sensing approaches using sun-induced chlorophyll fluorescence (SIF) hold the potential to directly as...
Article
The short revisit time of the Sentinel-2 (S2) constellation entails a large availability of remote sensing data, but S2 data have been rarely used to predict soil organic carbon (SOC) content. Thus, this study aims at comparing the capability of multispectral S2 and airborne hyperspectral remote sensing data for SOC prediction, and at the same time...
Article
Full-text available
The paper presents two procedures for the wavelength calibration, in the oxygen telluric absorption spectral bands (O2-A, λc = 687 nm and O2-B, λc = 760.6 nm), of field fixed-point spectrometers used for reflectance and Sun-induced fluorescence measurements. In the first case, Ne and Ar pen-type spectral lamps were employed, while the second approa...
Article
Full-text available
The atmospheric correction of optical remote sensing data requires the determination of aerosol and gas optical properties. A method is presented which allows the detection of the aerosol scattering effects from optical remote sensing data at spatial sampling intervals below 5 m in cloud-free situations from cast shadow pixels. The derived aerosol...
Article
Full-text available
In this paper, the accuracy of Suomi National Polar-orbiting Partnership (NPP) Visible Infrared Imaging Radiometer Suite (VIIRS) land surface albedo, which is derived from the direct estimation algorithm, was assessed using ground-based albedo observations from a wireless sensor network (WSN) over a heterogeneous cropland in the Huailai station, no...
Article
Full-text available
Assessing functional diversity from space can help predict productivity and stability of forest ecosystems at global scale using biodiversity–ecosystem functioning relationships. We present a new spatially continuous method to map regional patterns of tree functional diversity using combined laser scanning and imaging spectroscopy. The method does...
Presentation
Full-text available
Overview of functions, architecture and user benefits of the SPECCHIO spectral information system
Presentation
Full-text available
Definition of a mandatory metadata set, aligned with current international efforts in the spectroscopy community. The required and optional metadata of a spectral data set was investigated in depth in an OPTIMISE workshop titled “Ecosystem specific metadata definition” in 2017, hosted by the LIST institute in Luxembourg.
Article
Full-text available
Shifts of center wavelengths (CWLs) and related changes of full-widths at half-maximums (FWHMs) occur during in-flight data acquisitions of push-broom imaging spectrometers such as the airborne prism experiment (APEX). Combined with the spectrally changing properties of the dichroic coating that acts as a beam splitter between the visible and near...
Presentation
Full-text available
Introduces the requirement of in situ based CAL/VAL activities for the APEX airborne imaging spectrometer. Exemplifies the data import and data augmentation of APEX spectral ground control points in SPECCHIO. Shows the approaches for ASD inter channel jump correction and interactive calculation of reflectance factors.
Poster
Full-text available
Analytical Spectral Devices (ASD) field spectroradiometers [1] are one of the dominant family of instruments in the domain of remote sensing. The instruments are by default controlled by laptops running the proprietary RS3 software. The user interface has remained virtually static in the past decade and must be considered suboptimal by modern stand...
Technical Report
Full-text available
User manual for an iPad app to control ASD spectrometers. Serves as an example of a simple user interface with workflow support specific to field spectroscopy.
Article
Full-text available
Field spectroradiometers are often comprised of several spectral detectors to sample the full range of reflected solar irradiance. An example of such an instrument is the Analytical Spectral Devices (ASD) full-range spectroradiometer, featuring three spectral detectors to capture spectra between 350 and 2500 nm. The resulting spectra often exhibit...
Article
Full-text available
Accurate spectral calibration of satellite and airborne spectrometers is essential for remote sensing applications that rely on accurate knowledge of center wavelength (CW) positions and slit function parameters (SFP). We present a new in-flight spectral calibration algorithm that retrieves CWs and SFPs across a wide spectral range by fitting a hig...
Article
Field spectroscopy is increasingly used in various fields of science: either as a research tool in its own right or in support of airborne- or space-based optical instruments for calibration or validation purposes. Yet, while the use of the instruments appears deceptively simple, the processes of light and surface interactions are complex to be mea...
Article
Full-text available
Existing atmospheric correction methods retrieve surface reflectance keeping the same nominal spectral response functions (SRFs) as that of the airborne/spaceborne imaging spectrometer radiance data. Since the SRFs vary dependent on sensor type and configuration, the retrieved reflectance of the same ground object varies from sensor to sensor as we...
Technical Report
Full-text available
Remote Sensing and Geosciences Excursion addressing mineral resource exploration, satellite calibration/ validation and aquifer ecosystem research. SW-S Australia (Perth-Kalgoorlie-Dalhousie Springs- Adelaide)
Book
Full-text available
Earth Observation data are regarded as critical and essential information across multiple sectors in most countries around the world. However, for the EO data to be useful, to support decision making and reporting activities, the collection of image and field data sets needs to be accurate, precise and able to be reproduced following appropriate pr...
Research
Full-text available
Consumer-grade cameras (CGC) have advantageous characteristics for close-range vegetation monitoring, although there are limitations for many scientific applications. We discuss four categories of constraints, as well as potential modifications for effective vegetation monitoring. Reference: De Jong R, Hueni A, Nijland W, Torabzadeh H, Schaepman M...
Article
Full-text available
Resolving the spatial and temporal dynamics of gross primary productivity (GPP) of terrestrial ecosystems across different scales remains a challenge. Remote sensing is regarded as the solution to upscale point observations conducted at the ecosystem level, using the eddy covariance (EC) technique, to the landscape and global levels. In addition to...
Article
Sun-induced chlorophyll fluorescence (SIF) is a radiation flux emitted from chlorophyll molecules and is considered an indicator of the actual functional state of plant photosynthesis. The remote measurement of SIF opens a new perspective to assess actual photosynthesis at larger, ecologically relevant scales and provides an alternative approach to...
Article
Full-text available
Resolving the spatial and temporal dynamics of gross primary productivity (GPP) of terrestrial ecosystems across different scales remains a challenge. Remote sensing is regarded as the solution to upscale point observations conducted at the ecosystem level, using the eddy covariance (EC) technique, to the landscape and global levels. In addition to...
Book
Full-text available
Earth Observation data are regarded as critical and essential information across multiple sectors in most countries around the world. However, for the EO data to be useful, to support decision making and reporting activities, the collection of image and field data sets needs to be accurate, precise and able to be reproduced following appropriate pr...
Chapter
Full-text available
Field spectroscopy involves the study of the interrelationships between the spectral characteristics of objects and their biophysical attributes in the field environment (Bauer et al., 1986; Milton, 1987). When applied to vegetated surfaces, the spectral characteristics are function of the status, composition and structure of the elements measured....