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  • BB

  • Evaluation of MODIS Spectral Indices for Monitoring Hydrological Dynamics of a Small, Seasonally-Flooded Wetland in Southern Spain

    • Authors: Li, Linlin;  Advisor: -;  Participants: - (2015)

  • Monitoring spatio-temporal dynamics of hydrology in seasonally-flooded wetlands is important for water management and biodiversity conservation. Spectral data and derived indices from the Moderate Resolution Imaging Spectroradiometer (MODIS) have been used for hydrological monitoring of large wetlands. However, comparable studies for small wetlands (<25 km2) are lacking. Our aims are to examine whether MODIS-derived indices at 500-m spatial resolution can perform this task for small wetlands, and to compare the performance of various indices. First we evaluated if water levels are a good indicator for wetland inundation extent. A high correlation between water level and Landsat-derived inundation extent was found (R2 = 0.957). Secondly, we compared 10 years of water level fluctuatio...
  • BB

  • Automatic Counting of Large Mammals from Very High Resolution Panchromatic Satellite Imagery

    • Authors: Xue, Yifei.;  Advisor: -;  Participants: - (2017)

  • Estimating animal populations by direct counting is an essential component of wildlife conservation and management. However, conventional approaches (i.e., ground survey and aerial survey) have intrinsic constraints. Advances in image data capture and processing provide new opportunities for using applied remote sensing to count animals. Previous studies have demonstrated the feasibility of using very high resolution multispectral satellite images for animal detection, but to date, the practicality of detecting animals from space using panchromatic imagery has not been proven. This study demonstrates that it is possible to detect and count large mammals (e.g., wildebeests and zebras) from a single, very high resolution GeoEye-1 panchromatic image in open savanna. A novel semi-superv...
  • BB

  • Elephant movement closely tracks precipitation - driven vegetation dynamics in a Kenyan forest - savanna landscape

    • Authors: Bohrer, Gil;  Advisor: -;  Participants: - (2014)

  • This study investigates the ranging behavior of elephants in relation to precipitation-driven dynamics of vegetation. Movement data were acquired for five bachelors and five female family herds during three years in the Marsabit protected area in Kenya and changes in vegetation were mapped using MODIS normalized difference vegetation index time series (NDVI). In the study area, elevations of 650 to 1100 m.a.s.l experience two growth periods per year, while above 1100 m.a.s.l. growth periods last a year or longer.
  • LA

  • Characterization and remote detection of onshore hydrocarbon seep - induced alteration

    • Authors: van der Meer, F.D.; Salati, S.;  Advisor: -;  Participants: - (2014)

  • Thesis reviews previously published remote sensing studies on hydrocarbon seep-induced alteration; describes quantitatively the spatial pattern and spatial distribution of oil/gas seeps and their associated alterations with geological features; analyses the spectral and chemical characteristics of alteration induced by hydrocarbon seep from field data in order to getting a better understanding of oil and gas migration through the stratigraphy in relation to the various types of seeps in the Zagros belt and investigate the potential of detection of hydrocarbon seep-induced alteration for petroleum explorations; applied a template matching algorithm to ASTER data; investigates whether high spatial resolution WV2 satellite imagery and multispectral ASTER are able to detect gas-induced ...
  • LT

  • The role of remote sensing in geothermal exploration :Powerpoint

    • Authors: Hecker, C.A.; van der Meer, F.D.;  Advisor: -;  Participants: - (2014)

  • This lecture introduces: The role of remote sensing in geothermal exploration; Traditional exploration methods; Remote sensing of geothermal sites; Remote sensing: from hydro to geothermal – lessons learned future prospects.
  • LA

  • Identifying and classifying slum areas using remote sensing

    • Authors: Stein, A. ; Kohli, D.;  Advisor: -;  Participants: - (2015)

  • Thesis taking UN-HABITAT’s definition of slum household as a basis, this study proposes an ontological framework that conceptualizes slums using morphological indicators of the built environment; demonstrates a case of applicability of GSO and explores the transferability of an OOA method for slum classification developed on a single image area to other image areas; proposes a hierarchical method for slum detection by using a combination of texture and spatial metrics; demonstrates a method to quantify the uncertainties of slum interpretations performed by experts; presents the main research findings and conclusions corresponding to each research objective.
  • BB

  • Intercomparison of Surface Energy Fluxes Estimates from the FEST-EWB and TSEB Models over the Heterogeneous REFLEX 2012 Site (Barrax, Spain)

    • Authors: Corbari, Chiara;  Advisor: -;  Participants: - (2015)

  • An intercomparison between the Energy Water Balance model (FEST-EWB) and the Two-Source Energy Balance model (TSEB) is performed over a heterogeneous agricultural area. TSEB is a residual model which uses Land Surface Temperature (LST) from remote sensing as a main input parameter so that energy fluxes are computed instantaneously at the time of data acquisition. FEST-EWB is a hydrological model that predicts soil moisture and the surface energy fluxes on a continuous basis. LST is then a modelled variable. Ground and remote sensing data from the Regional Experiments For Land-atmosphere Exchanges (REFLEX) campaign in 2012 in Barrax gave the opportunity to validate and compare spatially distributed energy fluxes. The output of both models matches the ground observations quite well. H...
  • BB

  • Leaf area index retrieved from thermal hyperspectral data

    • Authors: Neinavaz, Elnaz;  Advisor: -;  Participants: - (2016)

  • Leaf area index (LAI) is an important essential biodiversity variable due to its role in many terrestrial ecosystem processes such as evapotranspiration, energy balance, and gas exchanges as well as plant growth potential. A novel approach presented here is the retrieval of LAI using thermal infrared (8–14 μm, TIR) measurements. Here, we evaluate LAI retrieval using TIR hyperspectral data. Canopy emissivity spectral measurements were recorded under controlled laboratory conditions using a MIDAC (M4401-F) illuminator Fourier Transform Infrared spectrometer for two plant species during which LAI was destructively measured. The accuracy of retrieval for LAI was then assessed using partial least square regression (PLSR) and narrow band index calculated in the form of normalized differen...
  • LA

  • Mapping spatial variation of foliar nitrogen using hyper spectral  remote sensing

    • Authors: Skidmore, A.K.; Wang, Z.;  Advisor: -;  Participants: - (2016)

  • Thesis assessed the ability of indirect estimation of nitrogen using the link with leaf traits retrieved from PROSPECT-5 model inversion; evaluated the feasibility of retrieving nitrogen through recalibrating PROSPECT- 5 by incorporating the effects of leaf protein and cellulose + lignin on leaf reflectance and transmittance; tested if nitrogen can still be retrieved if canopy structural effects were corrected for the canopy BRF; investigated to what extent nitrogen can be retrieved by linking a recalibrated PROSPECT-5 and canopy reflectance models such as INFORM.
  • BB

  • Simulation of Forest Evapotranspiration Using Time-Series Parameterization of the Surface Energy Balance System (SEBS) over the Qilian Mountains

    • Authors: Tian, Xin;  Advisor: -;  Participants: - (2013)

  • We propose a long-term parameterization scheme for two critical parameters, zero-plane displacement height (d) and aerodynamic roughness length (z0m), that we further use in the Surface Energy Balance System (SEBS). A sensitivity analysis of SEBS indicated that these two parameters largely impact the estimated sensible heat and latent heat fluxes. First, we calibrated regression relationships between measured forest vertical parameters (Lorey’s height and the frontal area index (FAI)) and forest aboveground biomass (AGB). Next, we derived the interannual Lorey’s height and FAI values from our calibrated regression models and corresponding forest AGB dynamics that were converted from interannual carbon fluxes, as simulated from two incorporated ecological models and a 2009 forest bas...