According to the calculation of wind scale and earthquake magnitude, this paper puts forward the concept of drought magnitude and disaster intensity and lays out a new method by quantitative calculation. Drought magnitude is the quantitative index that describes the scale of a drought, and disaster intensity of drought is the quantitative index to describe the loss caused by a drought. Both ind...

Drought is a major problematic phenomenon mostly for semi-arid areas of Iran. During drought periods, reduction in vegetation levels causes such problems as soil erosion, surface runoff, flood risk, etc. Therefore, the assessment of drought effects on plant covers is the most important issue. This research was conducted in 2015 using the extracted vegetation indices from Moderate Resolution Ima...

Drought is one of the most important weather-induced phenomena which may have severe impacts on different areas such as agriculture, economy, energy production, and society. A number of drought indices have been introduced and used in various countries to date. In the current study, four meteorological drought indices including Percent of Normal Precipitation Index (PNPI), Standard Index of Ann...

this study was conducted to determine drought tolerance genotypes with superiority in different stressed environments. to screening quantitative indices of drought tolerance, genotypes of safflower (carthamus tinctorius l.) were tested in a complete randomized block design with three replications under two different water regimes (irrigated and rainfed). significant positive correlation was fou...

Stomata1 closure during yriods of moisture deficiency should theoretically lead to elevated C/12C ratios as reduction of available C02 leads to diminished photosynthetic discrimination against 13c in favor of 12C. Stable-carbon isotope ratio chronologies developed from 5-yr tree-ring groups at 17 sites in six southwestern states were tested for a drought relationship by first fitting a spline c...

in order to evaluate drought tolerance of some aegilops triuncialis ecotypes a factorial experiment based on a completely randomized design was conducted under non-stress and drought stress (irrigation until 50% of heading) condition in the greenhouse of mohaghegh ardabili university in 2012. drought tolerance and susceptibility indices for grain yield were calculated and principal component an...

drought is among the natural disasters that causes heavy damages to water resources and makes managers face serious challenges. drought monitoring is one of the important measures to manage droughts. different indices and methods employing varied indicators, have been developed in this regard. in this paper it is aimed to compare two well known meteorological indices of spi and edi with a hydro...

in order to evaluate of drought tolerance in different canola varieties based on stress evaluation indices in terminal growth duration, an experiment was conducted as split-plot design on randomized complete block design with four replications at experimental field of seed and plant improvement institute, karaj in 2005 and 2006. results using stress susceptibility index (ssi) and tolerance inde...