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Dissertations / Theses on the topic 'Droughts – Remote sensing'

Author: Grafiati

Published: 4 June 2021

Last updated: 13 February 2022

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1

Ren, Xiaomeng, and University of Lethbridge Faculty of Arts and Science. "Agricultural vulnerability to drought in southern Alberta : a quantitative assessment." Thesis, Lethbridge, Alta. : University of Lethbridge, Faculty of Arts and Science, 2007, 2007. http://hdl.handle.net/10133/398.

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Agricultural vulnerability is generally referred to as the degree to which agricultural systems are likely to experience harm due to a stress. In this study, an existing analytical method to quantify vulnerability was adopted to assess the magnitude as well as the spatial pattern of agricultural vulnerability to varying drought conditions in Southern Alberta. Based on the farm reported data and remote sensing imagery, two empirical approaches were developed to implement vulnerability assessment in Southern Alberta at the quarter-section and 30 meter by 30 meter pixel levels. Cereal crop yield

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2

Almamalachy, Yousif. "Utilization of Remote Sensing in Drought Monitoring Over Iraq." Thesis, Portland State University, 2017. http://pqdtopen.proquest.com/#viewpdf?dispub=10283891.

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<p> Agricultural drought is a creeping disaster that overshadows the vegetative cover in general and cropland specifically in Iraq, a country that was well known for its agricultural production and fertile soil. In the recent years, the arable lands in Iraq experienced increasing land degradation that led to desertification, economic losses, food insecurity, and deteriorating environment. Remote sensing is employed in this study and four different indices are utilized, each of which is derived from MODIS satellite mission products. Agricultural drought maps are produced from 2003 to 2015 after

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De, la Barreda Bautista Betsabe. "Vegetation sensitivity to droughts (1982-2011) through remote sensing in the Yucatan Peninsula, Mexico." Thesis, University of Nottingham, 2017. http://eprints.nottingham.ac.uk/39822/.

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Ecosystems undergo permanent alteration and degradation as a result of the pressure exerted upon them by anthropogenic activities and natural causes. Amongst the natural causes, drought can have considerable impacts on vegetation productivity; these impacts include biomass reduction and changes in vegetation cycles, growth, and vitality. Such impacts have important implications for society, and understanding the impacts of drought in natural systems will help minimise vulnerability to it. The Yucatan Peninsula is a vulnerable area in climate change scenarios, where increased intensity and freq

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4

Chari, Martin Munashe. "Assessing the vulnerability of resource-poor households to disasters associated with climate variability using remote sensing and GIS techniques in the Nkonkobe Local Municipality, Eastern Cape Province, South Africa." Thesis, University of Fort Hare, 2016. http://hdl.handle.net/10353/2425.

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The main objective of the study was to assess the extent to which resource-poor households in selected villages of Nkonkobe Local Municipality in the Eastern Cape Province of South Africa are vulnerable to drought by using an improvised remote sensing and Geographic Information System (GIS)-based mapping approach. The research methodology was comprised of 1) assessment of vulnerability levels and 2) the calculation of established drought assessment indices comprising the Normalized Difference Vegetation Index (NDVI) and the Normalized Difference Water Index (NDWI) from wet-season Landsat image

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5

Domingo, Marimon Cristina. "Contributions to the knowledge of the multitemporal spatial patterns of the Iberian Peninsula droughts from a Geographic Information Science perspective." Doctoral thesis, Universitat Autònoma de Barcelona, 2016. http://hdl.handle.net/10803/379829.

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La sequera, una amenaça natural i insidiosa, és un fenomen complex que involucra processos climàtics i genera grans impactes ambientals i socioeconòmics. En els últims anys l’interès en el seguiment i en els efectes de les sequeres ha incrementat a causa de les situacions climàtiques extremes esdevingudes. Aquests episodis de sequera tenen implicacions sobre moltes Societal Benefit Areas (SBAs) abordades pel GEOSS (Global Earth Observation Systems of Sytems) de manera que es genera una interconnexió entre les diferents disciplines, com per exemple la sostenibilitat agrícola, la seguretat

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6

Wang, Lingli. "Remote sensing techniques for soil moisture and agricultural drought monitoring." Fairfax, VA : George Mason University, 2008. http://hdl.handle.net/1920/2991.

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Thesis (Ph.D.)--George Mason University, 2008.<br>Vita: p. 151. Thesis director: John J. Qu. Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Earth Systems and GeoInformation Sciences. Title from PDF t.p. (viewed June 30, 2008). Includes bibliographical references (p. 135-150). Also issued in print.

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Shamambo, Daniel Chiyeka. "Assimilation de données satellitaires pour le suivi des ressources en eau dans la zone Euro-Méditerranée." Thesis, Toulouse 3, 2020. http://www.theses.fr/2020TOU30143.

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Une estimation plus précise de l'état des variables des surfaces terrestres est requise afin d'améliorer notre capacité à comprendre, suivre et prévoir le cycle hydrologique terrestre dans diverses régions du monde. En particulier, les zones méditerranéennes sont souvent caractérisées par un déficit en eau du sol affectant la croissance de la végétation. Les dernières simulations du GIEC (Groupe d'Experts Intergouvernemental sur l'Evolution du Climat) indiquent qu'une augmentation de la fréquence des sécheresses et des vagues de chaleur dans la région Euro-Méditerranée est probable. Il est don

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8

El, Vilaly Mohamed Abd salam Mohamdy. "Drought Monitoring with Remote Sensing Based Land Surface Phenology Applications and Validation." Diss., The University of Arizona, 2013. http://hdl.handle.net/10150/301553.

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Droughts are a recurrent part of our climate, and are still considered to be one of the most complex and least understood of all natural hazards in terms of their impact on the environment. In recent years drought has become more common and more severe across the world. For more than a decade, the US southwest has faced extensive and persistent drought conditions that have impacted vegetation communities and local water resources. The focus of this work is achieving a better understanding of the impact of drought on the lands of the Hopi Tribe and Navajo Nation, situated in the Northeastern co

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9

Stong, Matthew Harold. "Development of Remote Sensing Techniques for Assessment of Salinity Induced Plant Stresses." Diss., The University of Arizona, 2008. http://hdl.handle.net/10150/194858.

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Salinity has been shown to reduce vegetative growth, crop quality, and yield in agricultural crops. Remote sensing is capable of providing data about large areas. This project was designed to induce salinity stress in a crop, pak choi, and thereafter monitor the response of the crop as expressed by its spectral reflectances. The project was conducted in the National Taiwan University Phytotron, and spectral data was collected using a GER 2600. Yield and soil salinity (ECe) were also measured. After three seasons of data were collected, wavelengths sensitive to salinity were selected. The

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10

Elujoba, Patrick Adetokunbo. "Detection and attribution of drought and oil-induced plant stress using hyperspectral remote sensing." Thesis, University of Dundee, 2018. https://discovery.dundee.ac.uk/en/studentTheses/9b41628d-2063-4df8-a1ac-63c72a565b3c.

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This study investigates the potential use of hyperspectral remote sensing in detecting stress in vegetation caused by both drought stress and hydrocarbon contamination of the soil. Spectral and plant biochemical measurements were taken from an in-situ field experiment and a glasshouse experiment at the James Hutton Institute, Invergowrie, U.K. The in-situ field experiment was part of an ongoing root restriction study of 10 barley genotypes, whilst the glasshouse experiment consisted of both drought and oil contamination of plants grown in pots. Two main biophysical parameters (chlorophyll and

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11

Champagne, Catherine. "Evaluation of Agricultural Soil Moisture Extremes in Canada Using Passive Microwave Remote Sensing." Thesis, Taylor and Francis, Elsevier Science, 2010. http://hdl.handle.net/10214/2918.

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This research examines the potential to use passive microwave remote sensing for measuring soil moisture extremes that impact agricultural areas in Canada. A validation was made of three passive microwave remote sensing soil moisture data sets, with weekly averaged values from the Land Parameter Retrieval Model (LPRM) applied to AMSR-E C/X-Band data providing the most accurate results (root mean squared error of 5 to 10%). A further evaluation of this data set against a spatially distributed in situ soil moisture network in Alberta suggests that this data set may be less accurate in regions wh

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12

Raper, Tyson B. "In-season Drought Monitoring| Testing Instrumentation and Developing Methods of Measurement Analysis." Thesis, University of Arkansas, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=3626302.

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<p> Soil moisture sensor use in crop production systems has the potential to give inference on plant water status for the purpose of irrigation scheduling and site-drought characterization. These processed measurements could serve as the framework on which to compile trial results across locations, thereby more accurately defining varietal yield response to drought. Still, the ability to characterize drought within a given field or initiate irrigations from these data hinge upon the ability of the instrument to characterize soil moisture at the sampled point and extrapolate that information

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13

Al, Arazah Ahmed. "Assessment of the hydrological status of Iraq using a combination of remote sensing and drought indices." Thesis, University of Reading, 2017. http://centaur.reading.ac.uk/76847/.

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This research deals with the assessment of drought over Iraq, a country which has been affected by recurrent droughts of medium to long duration, with serious socio-economic consequences. The overarching aim of this work is to identify reliable large-scale drought monitoring and assessment methods, using a range of freely available meteorological and remote sensing data, as well as model simulations of the water balance. The thesis starts with an overview of Iraq’s climate, soil, land use and socioeconomic issues, as well as an inventory of commonly used methods to assess and express drought.

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14

Coulthard, Bethany L., Ramzi Touchan, Kevin J. Anchukaitis, David M. Meko, and Fatih Sivrikaya. "Tree growth and vegetation activity at the ecosystem-scale in the eastern Mediterranean." IOP PUBLISHING LTD, 2017. http://hdl.handle.net/10150/625304.

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Linking annual tree growth with remotely-sensed terrestrial vegetation indices provides a basis for using tree rings as proxies for ecosystem primary productivity over large spatial and long temporal scales. In contrast with most previous tree ring/remote sensing studies that have focused on temperature-limited boreal and taiga environments, here we compare the normalized difference vegetation index (NDVI) with a network of Pinus brutia tree ring width chronologies collected along ecological gradients in semiarid Cyprus, where both radial tree growth and broader vegetation activity are control

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15

Ndlala, Noluthando. "Remote sensing drought impacts on wetland vegetation productivity at the Soetendalsvlei in the Heuningnes Catchment, South Africa." University of Western Cape, 2021. http://hdl.handle.net/11394/8329.

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>Magister Scientiae - MSc<br>This work aimed at assessing the response of wetland vegetation productivity to the 2014-2017 climate-induced drought at the Soetendalsvlei wetland system in the Western Cape province of South Africa. To achieve this objective, firstly a literature review on the progress of remotely sensed data applications in assessing and monitoring wetland vegetation productivity was conducted. The review elaborates on the role of remote sensing in monitoring and assessing wetland vegetation productivity, with a detailed discussion of the climate change and variability impacts o

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16

Melo, Davi de Carvalho Diniz. "Propagação de secas na bacia do Rio Paraná: do evento climático ao impacto hidrológico." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/18/18138/tde-31082018-164404/.

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Desastres naturais (secas, enchentes, etc) têm resultado em perdas humanas e grandes prejuízos financeiros em diversos lugares do mundo. Os recentes períodos de seca ocorridos na região sudeste do Brasil mostraram a importância de se dispor de estratégias de mitigação dos efeitos decorrentes desses eventos extremos. Um pré-requisito para prever impactos desses eventos no futuro, é compreender como os mesmos ocorreram no passado, caracterizando-os espacial e temporalmente. Diante do exposto, o objetivo deste trabalho é quantificar os impactos regionais no sistema hidrológico causados por evento

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Goldsby, Anthony Lee. "Establishment, drought tolerance and recovery, and canopy analysis of turfgrasses in the transition zone." Diss., Kansas State University, 2013. http://hdl.handle.net/2097/15416.

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Doctor of Philosophy<br>Department of Horticulture, Forestry, and Recreation Resources<br>Dale J. Bremer<br>Jack Fry<br>Increasing water scarcity may result in greater irrigation restrictions for turfgrass. Drought tolerance and recovery of Kentucky bluegrasses (Poa. pratensis L.) (KBG) were evaluated during and after 88 and 60 day dry downs in 2010 and 2011, respectively, under a rainout shelter. Changes in green coverage were evaluated with digital images. Green coverage declined slowest during dry downs and increased fastest during recoveries in the cultivar ‘Apollo’, indic

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18

Yang, Yang. "Non-contacting techniques for detecting plant drought stress in a closed environment." Connect to this title online, 2003. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1068499233.

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Thesis (Ph. D.)--Ohio State University, 2003.<br>Title from first page of PDF file. Document formatted into pages; contains xx, 245 p.; also includes graphics. Includes bibliographical references (p. 206-216).

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19

Sierra-Soler, Andres. "An original GIS and remote sensing protocol to detect agricultural drought effects on rainfed agro-ecosystems in semi-arid developing regions: a case study for Central Mexico." Thesis, McGill University, 2014. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=123308.

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Drought is a silent and pervasive phenomenon, it creeps up over weeks, months, and even years often without any warning, affecting ecosystems and human activity on a global scale. Globally droughts are one of the most devastating natural hazards in terms of the people affected and inflicting directly or indirectly economies, societies and ecosystems. As any natural hazard, the degree of exposure and the ability of systems to be resilient are directly related with the vulnerability of communities. Agricultural drought represents a great threat to poor farmers in semi-arid regions developing reg

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20

Makaudze, Ephias M. "Do seasonal climate forecasts and crop insurance really matter for smallholder farmers in Zimbabwe? Using contingent valuation method and remote sensing applications." Connect to this title online, 2005. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1110389049.

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Thesis (Ph. D.)--Ohio State University, 2005.<br>Title from first page of PDF file. Document formatted into pages; contains xiii, 155 p.; also includes map, graphics (some col.) Includes bibliographical references (p. 149-155). Available online via OhioLINK's ETD Center

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Dupigny-Giroux, Lesley-Ann. "Techniques for rainfall estimation and surface characterization over northern Brazil." Thesis, McGill University, 1996. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=40345.

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The sertao of northeast Brazil is a semiarid region characterized by recurring droughts. The vastness of the area (650,000 km$ sp2)$ poses a challenge to the effective monitoring of the impacts of drought at a scale that would be useful to the inhabitants of the sertao. Remote sensing data provide a viable way of assessing the extent and nature of drought across the landscape.<br>The work present a more effective algorithm to estimate rainfall from both the cold and warm cloud types present. Using a decision-tree methodology, the analysis yields rainfall estimates over the 0-21 mm range. Becau

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22

Caiserman, Arnaud. "Adapter les stratégies agricoles aux évolutions socio-économiques et climatiques en milieu méditerranéen : comparaison de l'usage de l'eau et des choix de plantes des agriculteurs dans la plaine de la Békaa (Liban) et de Marvdasht (Iran)." Thesis, Lyon, 2020. http://www.theses.fr/2020LYSE3009.

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D’après la carte des climats de Köppen, le climat méditerranéen semi-aride est présent dans plusieurs pays du Moyen-Orient, dont le Liban et l’Iran. Dans la perspective d’une régionalisation de la compréhension du défi de l'eau, deux plaines agricoles aux caractéristiques climatiques similaires ont été retenues comme zones d’étude : la plaine de la Békaa au Liban et la plaine de Marvdahst en Iran. La plaine de Marvdasht est légèrement plus aride. Avec le changement climatique, la Békaa ressemblera avant 2100 à la plaine de Marvdasht d’aujourd’hui. Il s’agit donc de connaitre les pratiques agri

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23

Messias, Pereira Nogueira Joana. "Apports de la télédétection globale pour la caractérisation et modélisation du régime des incendies au Brésil : vers une approche des patchs de feux." Thesis, Montpellier, 2016. http://www.theses.fr/2016MONTT126.

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Les incendies sont des perturbations intrinsèques au fonctionnement des écosystèmes agissant sur la distribution des espèces, les cycles biogéochimiques et les interactions biosphère/atmosphère. La distribution spatiale et temporelle des surfaces brûlées résulte principalement d'un compromis entre la disponibilité en biomasse combustible et son état hydrique. Ainsi, caractériser et modéliser un régime d'incendie repose donc sur une évaluation principalement de la saisonnalité et l'intensité de la sécheresse. Dans les écosystèmes fortement soumis aux incendies comme les savanes, biome le plus a

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Szczypta, Camille. "Hydrologie spatiale pour le suivi des sécheresses du bassin méditerranéen." Thesis, Toulouse, INPT, 2012. http://www.theses.fr/2012INPT0108/document.

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Le climat du bassin méditerranéen est caractérise par un fort impact du déficit hydrique sur la croissance de la végétation. Dans ces régions fréquemment affectées par les sècheresses, l'humidité des sols est un facteur essentiel des processus hydrologiques et de la croissance de la végétation. Des études climatiques récentes ont montré qu'il est probable que le changement climatique accroitra encore l'impact des sècheresses et la pression sur les ressources en eau. Le bassin méditerranéen peut donc être qualifié de "point chaud" du changement climatique. Dans ce contexte, il est important de

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25

Nasser, Thierry Tarek. "Evaluation et impact de la sécheresse sur une région agricole : Cas de la plaine irriguée de la Beqaa." Thesis, Orléans, 2019. http://www.theses.fr/2019ORLE1169.

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La plaine intérieure de la Beqaa est considérée comme le grenier agricole du Liban. Dans cette région, la sécheresse représente une problématique majeure, qu’elle soit d’origine climatique ou due à une gestion mal conduite de la ressource. Ce travail s’intéresse à la sécheresse agricole dans la région semi-aride de la plaine de la Beqaa. Afin de suivre l’évolution de son intensité, on a utilisé principalement les méthodes de la télédétection. Les années les plus sèches ont été repérées à partir d’un indicateur de sécheresse, Vegetation Health Index (VHI), combinant un indicateur de végétation

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Mezrag, Mohamed. "Dynamique environnementale des zones steppiques à Djelfa (Algérie) : caractérisation par télédétection des changements du couvert végétal et des processus d'ensablement." Thesis, Lyon, 2018. http://www.theses.fr/2018LYSE2080/document.

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Les steppes algériennes sont situées entre le Sahara et la méditerranée. Le climat semi-aride autorise le développement d’une végétation naturelle et le maintien du pâturage. Ce milieu, à équilibre environnement fragile est le théâtre de changements, avec le déclin du nomadisme, la transformation des éleveurs en agro-pasteurs, l’extension de l’agriculture et l’urbanisation. Nous abordons ces points en articulant le passé au présent pour mettre en lumière le poids de l’activité d’élevage fortement enracinée dans la polarisation des tendances actuelles.Basé sur une méthode quantitative par téléd

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Khaled, Elazab Abdelhalim. "Novel phenotyping and monitoring approaches to assess cereal performance under abiotic stress conditions = Nuevos enfoques de fenotipeado y monitoreo de cultivos para evaluar el rendimiento de cereales cultivados en diferentes condiciones de estrés abiótico." Doctoral thesis, Universitat de Barcelona, 2015. http://hdl.handle.net/10803/300434.

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Cereals are the basis of the normal diet in most Mediterranean countries and it is estimated that they account for 35-50% of the regional populations’ dietary energy consumption. Water deficit is the main constraint limiting cereal productivity in the Mediterranean regions. Crop management and breeding may improve the performance of cereals under such stress conditions. However, the lack of efficient tools to monitor the performance of agronomical practices or to undertake appropriate phenotyping in breeding programs limits the efficiency of both avenues. Novel tools to monitor the cereals

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Persendt, Frans Carel. "Drought risk analysis using remote sensing and GIS in the Oshikoto region, Namibia." Thesis, 2009.

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Drought is a recurrent climatic process that occurs with uneven temporal and spatial characteristics over broad areas and over an extended period of time. Therefore, detecting drought onsets and ends as well as assessing drought severity using satellite-derived information is essential. This should be especially the case in an arid country like Namibia where drought is part of Namibia’s climatology. It is believed that proper planning and research using near real-time data can curb the devastating environmental and socio-economic impacts of drought. Weather data used currently are often from a

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Mühlbauer, Stefan Ludwig. "Recent droughts and the impact of North Atlantic Oscillation in Iberia; a spatiotemporal analysis based on vegetation temperature condition Index (VTCI)." Master's thesis, 2013. http://hdl.handle.net/10362/9233.

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Dissertation submitted in partial fulfillment of the requirements for the Degree of Master of Science in Geospatial Technologies.<br>Drought is a complex phenomenon that afflicts huge areas worldwide with high spatial and temporal variability. Being under influence of the Mediterranean climate the Iberian Peninsula is per se prone to droughts. In this study, we applied the Vegetation Condition Temperature Index for a spatiotemporal drought analysis in Iberia. As a compound remote sensing drought index VTCI incorporates information on Normalized Difference Vegetation Index (NDVI) and Land S

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"Monitoring spatio-temporal variations of vegetation responses to drought with remotely sensed data." 2012. http://library.cuhk.edu.hk/record=b5549558.

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干旱是全球范围内的灾害。协同利用遥感数据和气象数据来研究植被对干旱的响应并进行干旱评估和监测，对于减少干旱损失，制定决策和农业管理都有重大的现实意义。<br>本研究提出了两种新的处理多时相遥感数据的方法：一种是基于无云影像频域分析的植被时间序列获取；另一种是基于时间序列主成份分析的MODIS混合象元信息提取。这两种方法可以分别用于时间序列数据的预处理和估算生态干扰发生时陆地植被覆盖的变化。<br>本研究开展了地面试验，用ASD地面高光谱仪和SPAD502叶绿素仪测定了在控制梯度干旱下的玉米叶片光谱和叶绿素含量的动态变化。研究表明：随着干旱的加剧, 叶片光谱反射率也会相应增加。统计分析表明叶片510 nm和690 nm处的反射率可以用于玉米干旱的预警。本研究基于不同干旱程度和玉米不同发育时期的光谱数据，全面探讨了光谱变量和光谱指数对干旱胁迫下叶绿素变化的敏感性。<br>本研究探讨了中国的作物长势与气象因子的关系，首先基于温度，降水，光照和NDVI数据将中国分为7个研究区，然后基于多元线性回归提取了每个研究区在19822006年间限制作物生长的关键气候因子。研究表明在春季和夏季，温度，降水, 光照对作物NDVI的影响（R²>=0.35）要大于秋季和冬季 (R²<=0.14). 在分区1-3（华北，东北）中，全年作物NDVI呈现显著增加的趋势(p<0.1)，而在华南地区则没有明显的趋势。

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Dlamini, Livelethu. "Modelling of standardised precipitation index using remote sensing for improved drought monitoring." Thesis, 2014.

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The South African Weather Service (SAWS) has reported a decline in the number of rainfall observation stations due to inadequate financial resources to meet maintenance costs. This reduction in rainfall stations complicates the calculation of the rainfall-based Standardised Precipitation Index (SPI) drought index mainly owing to the sparse distribution of these stations and the high variability of rainfall. The SPI is used to inform short-term drought mitigation and relief decisions. This study investigates the determination of a spatially improved Standardised Precipitation Index (SPI) using

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"Natural Desert and Human Controlled Landscapes: Remote Sensing of LULC Response to Drought." Doctoral diss., 2014. http://hdl.handle.net/2286/R.I.24759.

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abstract: Droughts are a common phenomenon of the arid South-west USA climate. Despite water limitations, the region has been substantially transformed by agriculture and urbanization. The water requirements to support these human activities along with the projected increase in droughts intensity and frequency challenge long term sustainability and water security, thus the need to spatially and temporally characterize land use/land cover response to drought and quantify water consumption is crucial. This dissertation evaluates changes in `undisturbed' desert vegetation in response to water ava

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HONG, MU. "Evaluating small unmanned aerial systems for detecting drought stress in turfgrass." Thesis, 2019. http://hdl.handle.net/2097/39434.

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Master of Science<br>Department of Horticulture and Natural Resources<br>Dale J. Bremer<br>Recent advances in small unmanned aerial systems (sUAS) may provide rapid and accurate methods for turf research and management. The study was to evaluate early drought detection ability of ultra-high resolution remote sensing with sUAS technology, and compare it with traditional techniques on fairway-height ‘Declaration’ creeping bentgrass (Agrostis stolonifera L.) treated from severe deficit to well-watered irrigation (15, 30, 50, 65, 80, and 100% evapotranspiration replacement). Airborne measurements

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Chakraborty, Tanmoy. "Multi-scale assessment of drought-induced forest dieback." Master's thesis, 2020. http://hdl.handle.net/10362/94403.

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Dissertation submitted in partial fulfilment of the requirements for the degree of Master of Science in Geospatial Technologies<br>Drought has been intensified over the years and will continue to worsen due to climate change. Existing works have focused their attention on crops rather than forests. Adverse effects are felt by all flora and fauna but the impact of the recent droughts on forest ecosystems is still unknown. Greater root depth allows them to withstand the immediate impacts of drought in contrast to crops and other vegetation. This study aims to see not only the interaction between

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Abdi, Omid. "Climate-Triggered Drought as Causes for Different Degradation Types of Natural Forests: A Multitemporal Remote Sensing Analysis in NE Iran." 2019. https://tud.qucosa.de/id/qucosa%3A72323.

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Climate-triggered forest disturbances are increasing either by drought or by other climate extremes. Droughts can change the structure and function of forests in long-term or cause large-scale disturbances such as tree mortality, forest fires and insect outbreaks in short-term. Traditional approaches such as dendroclimatological surveys could retrieve the long-term responses of forest trees to drought conditions; however, they are restricted to individual trees or local forest stands. Therefore, multitemporal satellite-based approaches are progressing for holistic assessment of climate-induced

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Sung, Chan Yong. "Hydrologic and Ecological Effects of Watershed Urbanization: Implication for Watershed Management in Hillslope Regions." Thesis, 2010. http://hdl.handle.net/1969.1/ETD-TAMU-2010-05-7962.

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In this study, I examined the effect of watershed urbanization on the invasion of alien woody species in riparian forests. This study was conducted in three major steps: 1) estimating the degree of watershed urbanization using impervious surface maps extracted from remote sensing images; 2) examining the effect of urbanization on hydrologic regime; and 3) investigating a relationship between watershed urbanization and ecosystem invasibility of a riparian forest. I studied twelve riparian forests along urban-rural gradients in Austin, Texas. Hydrologic regimes were quantified by transfer functi

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Ndlela, Bekithemba. "Impact of climate change on fresh water resources of Elliot town in the Eastern Cape." Diss., 2015. http://hdl.handle.net/10500/20157.

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Climate change and variability have great impact on the hydrological cycle and consequently on the availability of water resources. Variations in temperature and precipitation trends that are occurring are a consequent of the increase in the concentrations of greenhouse gases, which are subsequently affecting the hydrological cycle. This in turn affects water quantity and quality, which is essential for agriculture, domestic and industrial uses. This study, done in Elliot Town and the surrounding areas of Sakhisizwe Municipality in the Eastern Cape Province of South Africa, evaluates how cli

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