نتایج جستجو برای: drought monitoring

تعداد نتایج: 328710  

2010
M. Ebrahimi A. A. Matkan

Rainfall, soil moisture, increasing temperature and changes in vegetation cover are the most important parameters effecting drought. Therefore, analysis of vegetation fraction and soil spectral signature, especially in red and infra red bands, are essential in drought estimation using remote sensing. In this study, Modified Perpendicular Drought Index (MPDI), which uses Vegetation Fraction (VF)...

2017
Chao Zhang Catherine Preece Iolanda Filella Gerard Farré-Armengol Josep Peñuelas

The photochemical reflectance index (PRI) and red-edge region of the spectrum are known to be sensitive to plant physiological processes, and through measurement of these optical signals it is possible to use non-invasive remote sensing to monitor the plant photosynthetic status in response to environmental stresses such as drought. We conducted a greenhouse experiment using Quercus ilex, a Med...

The aim of this research is to investigate drought stress in rangeland rangelands in Ardabil province. According to the monthly rainfall data, 4 synoptic stations of Ardebil province (Ardebil, Khalkhal, Meshgin Shahr and Parsabad Moghan) during the statistical period of 2016-1996 were used to calculate drought index (SEPI) index for 4 periods of 1, 3, 6 and 9 months. Landsat TM and OLI satellit...

Drought is a natural and climatic phenomenon that occurs in world wide areas every year and occurrence becomes an inevitable issue. This phenomenon is impaired in ecosystem. Arid rangeland ecosystems are a significant part of our land that is brittle systems that climatic changes are useful to simply unfounded destruction. Therefore, drought identifying and monitoring valid descriptive statisti...

2016
Steven P. Norman Frank H. Koch William W. Hargrove

Efforts to monitor the broad-scale impacts of drought on forests often come up short. Drought is a direct stressor of forests as well as a driver of secondary disturbance agents, making a full accounting of drought impacts challenging. General impacts can be inferred from moisture deficits quantified using precipitation and temperature measurements. However, derived meteorological indices may n...

ژورنال: علوم آب و خاک 2019

Droughts are natural events and could lead to declining surface water quality of regional basin. Understanding the complex impacts of drought may help authorities to monitor changes in different regional basin and to make appropriate decision on development of a river basin management plan. In this study 20 years annual precipitation time series from 1994-2013 from 7 synoptic weather stations l...

Today, there are many factors affecting watersheds, consequently changing natural ecosystems succession. The aim of this study was to investigate the effect of drought events on land use changes at Doiraj Watershed of Ilam Province from 1996 to 2015. For this purpose, Landsat satellite images were used for land use change monitoring and Standardized Precipitation Index (SPI) was applied for dro...

2017
Matthew Rodell Brian D. Wardlow Martha C. Anderson James P. Verdin

11.1 INTRODUCTION Near-surface wetness conditions change rapidly with the weather, which limits their usefulness as drought indicators. Deeper stores of water, including root-zone soil wetness and groundwater, portend longer-term weather trends and climate variations ; thus, they are well suited for quantifying droughts. However, the existing in situ networks for monitoring these variables suff...

Journal: :IJSDIR 2012
Andrej Ceglar Barbara Medved-Cvikl Enrique Moran-Tejeda Sergio Vicente-Serrano Lucka Kajfez-Bogataj

Real-time information on the development of the drought conditions is one of the fundamental requisites for reinforcing the drought mitigation and preparedness. The EuroGEOSS interoperability approach promotes the development of monitoring and early warning systems based on real-time information. Different climatic databases, which are based on publicly available meteorological information, are...

2015
Adeyinka K. Akanbi Muthoni Masinde

Technological advancement in Wireless Sensor Networks (WSN) has made it become an invaluable component of a reliable environmental monitoring system; they form the ’digital skin’ through which to ’sense’ and collect the context of the surroundings and provides information on the process leading to complex events such as drought. However, these environmental properties are measured by various he...

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