Towards Mapping of Soil Crust Using Multispectral Imaging

Soil crusts and surface roughness are properties which are highly dynamic in both space and time that change in response to biotic processes, meteorological conditions and farming operations. These factors, however, are difficult to quantify and are usually described using simplified expert-based classes. This hampers a clear identification of the controlling factors and their relation to soil erosion and sediment generation processes. The availability of new small portable multispectral cameras offers the potential to study soil surface dynamics at a high spatial and temporal resolution. The objective of this study was to analyse the relationship between soil crusting, represented by cumulative rainfall kinetic energy, and soil surface reflectance, as derived from vis-NIR multispectral imaging. We designed a series of rainfall-soil surface experiments to disentangle the effects of soil crusting on spectral reflectance factors from those related to surface micro-scale roughness. Partial least squared regression (PLSR) models were developed to predict both kinetic energy and roughness from multispectral images. We evaluated different roughness removal methods which were based on the transformation of reflectance through standard normal variate (SNV) and roughness thresholding using high resolution digital elevation models. Furthermore, we assigned the light scattering effect related to roughness in the multispectral spatial domain by calculating the inter-quantile range of the reflectance values in a kernel. Our experiments and workflow demonstrate that it is possible to model crust development, using rainfall kinetic energy as a proxy, from vis-NIR based multispectral imaging.

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On the Scales Associated with Near-Infrared Reflectance Difference Spectra

Applied Spectroscopy ◽

10.1366/0003702953964615 ◽

1995 ◽

Vol 49 (6) ◽

pp. 765-772 ◽

Cited By ~ 75

Author(s):

M. S. Dhanoa ◽

S. J. Lister ◽

R. J. Barnes

Keyword(s):

Near Infrared ◽

Scatter Correction ◽

The Other ◽

Difference Spectra ◽

Near Infrared Reflectance ◽

Standard Normal Variate ◽

Near Infrared Spectra ◽

Standard Normal ◽

Relationship Of ◽

The Relationship

Scale differences of individual near-infrared spectra are identified when set-independent standard normal variate (SNV) and de-trend (DT) transformations are applied in either SNV followed by DT or DT then SNV order. The relationship of set-dependent multiplicative scatter correction (MSC) to SNV is also referred to. A simple correction factor is proposed to convert derived spectra from one order to the other. It is suggested that the suitable order for the study of changes using difference spectra (when removing baselines) should be DT followed by SNV, which leads to all derived spectra on the scale of mean zero and variance equal to one. If baselines are identical, then SNV scale spectra can be used to calculate differences.

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Mass Exchange of Water and Soil on the Soil Surface in the Rainfall Splash Erosion

Frontiers in Earth Science ◽

10.3389/feart.2021.739804 ◽

2021 ◽

Vol 9 ◽

Author(s):

Sun Sanxiang ◽

Zhang Yunxia ◽

Lei Pengshui

Keyword(s):

Kinetic Energy ◽

Mass Exchange ◽

Soil Surface ◽

Terminal Velocity ◽

Erosion Process ◽

Liquid Drops ◽

Splash Erosion ◽

The Impact ◽

The Relationship ◽

Soil Interface

This research aims to unfold the mass exchange mechanism of water and soil on the soil surface in the rainfall splash erosion process. We regard the rainfall splash erosion process as a collision process between the raindrop and the soil particle on the soil interface. This recognition allows us to incorporate research approaches from the spring vibrator model, which has been developed for simulating the impact of liquid drops on solid surface. We further argue that because a same set of factors determine the splash amount and infiltration amount and it is relatively simpler to observe the infiltration amount, an investigation into the relationship between the splash amount and infiltration amount would be able to provide a new channel for quantifying the splash erosion. This recognition leads us to examining the relationship between single raindrop, rainfall kinetic energy and splash erosion from both theoretical and empirical angles, with an emphasis on the relationship between the infiltration amount and the splash erosion. Such an investigation would add value to the collective effort to establish mass exchange law in water-soil interface during rainfall splash erosion. It is found that during the rainfall splash process, the splash erosion is proportional to the rainfall kinetic energy; and has a linear relation to the infiltration amount, with the rainfall intensity as one of important parameters and the slope depending on the unit conversation of the infiltration amount and the splash erosion. If the units of two items are same, the slope is the ratio of the soil and water density, and the splash erosion velocity of the rainfall is half of the rainfall terminal velocity. The single raindrop kinetic energy and the splash erosion have a quadratic parabola relation, and the splash velocity is about 1/3 of single raindrop terminal velocity.

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Machine Learning-Based Prediction of Selected Parameters of Commercial Biomass Pellets Using Line Scan Near Infrared-Hyperspectral Image

Processes ◽

10.3390/pr9020316 ◽

2021 ◽

Vol 9 (2) ◽

pp. 316

Author(s):

Lakkana Pitak ◽

Kittipong Laloon ◽

Seree Wongpichet ◽

Panmanas Sirisomboon ◽

Jetsada Posom

Keyword(s):

Near Infrared ◽

Hyperspectral Image ◽

Thermal Conversion ◽

High Energy ◽

Volatile Matter ◽

Successive Projections Algorithm ◽

Color Distribution ◽

Standard Normal Variate ◽

Distribution Mapping ◽

Standard Normal

Biomass pellets are required as a source of energy because of their abundant and high energy. The rapid measurement of pellets is used to control the biomass quality during the production process. The objective of this work was to use near infrared (NIR) hyperspectral images for predicting the properties, i.e., fuel ratio (FR), volatile matter (VM), fixed carbon (FC), and ash content (A), of commercial biomass pellets. Models were developed using either full spectra or different spatial wavelengths, i.e., interval successive projections algorithm (iSPA) and interval genetic algorithm (iGA), wavelengths and different spectral preprocessing techniques. Their performances were then compared. The optimal model for predicting FR could be created with second derivative (D2) spectra with iSPA-100 wavelengths, while VM, FC, and A could be predicted using standard normal variate (SNV) spectra with iSPA-100 wavelengths. The models for predicting FR, VM, FC, and A provided R2 values of 0.75, 0.81, 0.82, and 0.87, respectively. Finally, the prediction of the biomass pellets’ properties under color distribution mapping was able to track pellet quality to control and monitor quality during the operation of the thermal conversion process and can be intuitively used for applications with screening.

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Surface kinetic energy transfer in surface quasi-geostrophic flows

Journal of Fluid Mechanics ◽

10.1017/s0022112008001110 ◽

2008 ◽

Vol 604 ◽

pp. 165-174 ◽

Cited By ~ 68

Author(s):

XAVIER CAPET ◽

PATRICE KLEIN ◽

BACH LIEN HUA ◽

GUILLAUME LAPEYRE ◽

JAMES C. MCWILLIAMS

Keyword(s):

Kinetic Energy ◽

Surface Velocity ◽

Small Scale ◽

Surface Dynamics ◽

Spectral Flux ◽

Advection Term ◽

Wide Range ◽

Geostrophic Flows ◽

Scale Range ◽

Density Variance

The relevance of surface quasi-geostrophic dynamics (SQG) to the upper ocean and the atmospheric tropopause has been recently demonstrated in a wide range of conditions. Within this context, the properties of SQG in terms of kinetic energy (KE) transfers at the surface are revisited and further explored. Two well-known and important properties of SQG characterize the surface dynamics: (i) the identity between surface velocity and density spectra (when appropriately scaled) and (ii) the existence of a forward cascade for surface density variance. Here we show numerically and analytically that (i) and (ii) do not imply a forward cascade of surface KE (through the advection term in the KE budget). On the contrary, advection by the geostrophic flow primarily induces an inverse cascade of surface KE on a large range of scales. This spectral flux is locally compensated by a KE source that is related to surface frontogenesis. The subsequent spectral budget resembles those exhibited by more complex systems (primitive equations or Boussinesq models) and observations, which strengthens the relevance of SQG for the description of ocean/atmosphere dynamics near vertical boundaries. The main weakness of SQG however is in the small-scale range (scales smaller than 20–30 km in the ocean) where it poorly represents the forward KE cascade observed in non-QG numerical simulations.

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Remediation-related monitoring of heavy metal concentration of contaminated Technosol using hyperspectral measurements

10.5194/egusphere-egu21-11479 ◽

2021 ◽

Author(s):

Friederike Kaestner ◽

Magdalena Sut-Lohmann ◽

Thomas Raab ◽

Hannes Feilhauer ◽

Sabine Chabrillat

Keyword(s):

Heavy Metal ◽

Random Forest ◽

Metal Concentration ◽

Strong Dependence ◽

Scatter Correction ◽

Heavy Metal Concentration ◽

Standard Normal Variate ◽

Multiplicative Scatter Correction ◽

Second Derivatives ◽

Standard Normal

Across Europe there are 2.5 million potentially contaminated sites, approximately one third have already been identified and around 15% have been sanitized. Phytoremediation is a well-established technique to tackle this problem and to rehabilitate soil. However, remediation methods, such as biological treatments with microorganisms or phytoremediation with trees, are still relatively time consuming. A fast monitoring of changes in heavy metal content over time in contaminated soils with hyperspectral spectroscopy is one of the first key factors to improve and control existing bioremediation methods.At former sewage farms near Ragow (Brandenburg, Germany), 110 soil samples with different contamination levels were taken at a depth between 15-20 cm. These samples were prepared for hyperspectral measurements using the HySpex system under laboratory conditions, combing a VNIR (400-1000 nm) and a SWIR (1000-2500 nm) line-scan detector. Different spectral pre-processing methods, including continuum removal, first and second derivatives, standard normal variate, normalisation and multiplicative scatter correction, with two established estimation models such as Partial Least Squares Regression (PLSR) and Random Forest Regression (RFR), were applied to predict the heavy metal concentration (Ba, Ni, Cr, Cu) of this specific Technosol. The coefficient of determination (R2) shows for Ba and Ni values between 0.50 (RMSE: 9%) and 0.61 (RMSE: 6%) for the PLSR and between 0.84 (RMSE: 0.03%) and 0.91 (RMSE: 0.02%) for the RFR model. The results for Cu and Cr show values between 0.57 (RMSE: 17.9%) and 0.69 (RMSE: 15%) for the PLSR and 0.86 (0.12%) and 0.93 (0.01%) for the RFR model. The pre-processing method, which improve the robustness and performance of both models best, is multiplicative scatter correction followed by the standard normal variate for the first and second derivatives. Random Forest in a first approach seems to deliver better modeling performances. Still, the pronounced differences between PLSR and RFR fits indicate a strong dependence of the results on the respective modelling technique. This effect is subject to further investigation and will be addressed in the upcoming analysis steps.

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Seasonal emergence of selected summer annual weed species in dependence on soil temperature

Plant Soil and Environment ◽

10.17221/22/2010-pse ◽

2010 ◽

Vol 56 (No. 9) ◽

pp. 444-450 ◽

Cited By ~ 2

Author(s):

M. Jursík ◽

J. Holec ◽

J. Soukup ◽

V. Venclová

Keyword(s):

Chenopodium Album ◽

Soil Surface ◽

Main Field ◽

Weed Species ◽

Soil Temperatures ◽

Field Emergence ◽

The Relationship ◽

Galinsoga Ciliata ◽

Surface Layer Temperature ◽

Mass Field

This study aimed to describe emergence cycles of selected weed species under Central European conditions in relation to cumulative soil temperatures from the start of the vegetation season. Emergence of Chenopodium album, Echinochloa crus-galli, Galinsoga ciliata, and Abutilon theophrasti was observed from March to October during the period 2001–2006 at two locations. The beginning of main field emergence was determined as the day when the sum of effective hour temperatures was achieved, and was detected from the second decade of April to early May for C. album, in the second decade of May for E. crus-galli, from late April to the beginning of May for G. ciliata, and from the end of April to mid-May for A. theophrasti. The relationship between cumulative soil surface layer temperature and weed mass field emergence at the beginning of the growing season is very direct (differences ±7 days) – but only when soil moisture is sufficient. In a drier spring, the beginning of mass field emergence occurs with 1–4 weeks of delay and field emergence is usually slower and protracted.

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Potential of Digital Elevation Topographic Maps reveal the history of the region: comparing Those Maps with Marsh data in the early Meiji Period

Abstracts of the ICA ◽

10.5194/ica-abs-1-134-2019 ◽

2019 ◽

Vol 1 ◽

pp. 1-2

Author(s):

Masatoshi Ideto ◽

Yuki Kurisu ◽

Hideyuki Toishigawa

Keyword(s):

Social Life ◽

Topographic Map ◽

Thematic Maps ◽

Geospatial Information ◽

Meiji Period ◽

Topographic Information ◽

Digital Elevation ◽

New Findings ◽

History Of ◽

The Relationship

Abstract. Landform of lowland is remains of the natural disasters and the history. Residents of this area are influenced of the landform with history of natural disaster. Therefore, there is an inseparable relationship between topography and social life. At Geospatial Information Authority of Japan (GSI), we are creating Thematic maps which clearly express topographic information. We also create, Thematic maps which distinguish the topography from the formation of the land. New findings can be obtained by considering these thematic maps in combination. In this paper, we study the relationship between landform and history of Tokyo by comparing “Digital Elevation Topographic Map” and “Marsh data in the early Meiji Period”. (This early Meiji Period here is the 1880s.)

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PREDIKSI TOTAL PADATAN TERLARUT BUAH MELON GOLDEN (Cucumis melo L.) MENGGUNAKAN VIS-SWNIRS DAN ANALISIS MULTIVARIAT

Jurnal Penelitian Saintek ◽

10.21831/jps.v25i2.34487 ◽

2020 ◽

Vol 25 (2) ◽

Author(s):

Yuda Hadiwijaya ◽

Kusumiyati Kusumiyati ◽

Agus Arip Munawar

Keyword(s):

Cucumis Melo ◽

Partial Least Squares Regression ◽

Scatter Correction ◽

Least Squares Regression ◽

Orthogonal Signal ◽

Standard Normal Variate ◽

Orthogonal Signal Correction ◽

Signal Correction ◽

Standard Normal ◽

Cucumis Melo L

Penelitian ini bertujuan memprediksi total padatan terlarut buah melon golden menggunakan Vis-SWNIRS dan analisis multivariat. 82 sampel buah melon golden dipanen untuk dianalisis di Laboratorium Hortikultura, Fakultas Pertanian, Universitas Padjadjaran. Nirvana AG410 spectrometer dengan rentang panjang gelombang 300 sampai 1050 nm digunakan untuk pengambilan data spektra pada sampel buah melon utuh. Metode koreksi spektra yang digunakan yaitu standard normal variate (SNV), multiplicative scatter correction (MSC), dan orthogonal signal correction (OSC). Pemodelan kalibrasi dilakukan menggunakan partial least squares regression (PLSR). Hasil penelitian menunjukkan bahwa penggunaan metode koreksi spektra OSC menampikan model kalibrasi terbaik dibandingkan spektra original dan 2 spektra lainnya yang telah dikoreksi. Koefisien determinasi pada spektra OSC memperlihatkan nilai R2 tertinggi yaitu 0.99, disamping itu nilai ratio performance to deviation (RPD) yang diperoleh sebesar 3.40. Hal ini membuktikan bahwa total padatan terlarut buah melon golden dapat diprediksi dengan akurasi yang tinggi menggunakan Vis-SWNIRS dan analisis multivariat.

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THEORETICAL MODELLING STUDY ON THE RELATIONSHIP BETWEEN MULTI-FREQUENCY MICROWAVE VEGETATION INDEX AND VEGETATION PROPERTIES (OPTICAL DEPTH AND SINGLE SCATTERING ALBEDO)

ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences ◽

10.5194/isprs-archives-xlii-3-1623-2018 ◽

2018 ◽

Vol XLII-3 ◽

pp. 1623-1627

Author(s):

S. Talebi ◽

J. Shi ◽

T. Zhao

Keyword(s):

Optical Depth ◽

Vegetation Index ◽

Vegetation Indices ◽

Soil Surface ◽

Single Scattering ◽

Single Scattering Albedo ◽

Theoretical Modelling ◽

Vegetation Monitoring ◽

Scattering Effects ◽

The Relationship

This paper presents a theoretical study of derivation Microwave Vegetation Indices (MVIs) in different pairs of frequencies using two methods. In the first method calculating MVI in different frequencies based on Matrix Doubling Model (to take in to account multi scattering effects) has been done and analyzed in various soil properties. The second method was based on MVI theoretical basis and its independency to underlying soil surface signals. Comparing the results from two methods with vegetation properties (single scattering albedo and optical depth) indicated partial correlation between MVI from first method and optical depth, and full correlation between MVI from second method and vegetation properties. The second method to derive MVI can be used widely in global microwave vegetation monitoring.

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