The goal of the WMO Expert Meeting on Agricultural Drought Indices was to move forward in the selection of a single drought index that would be used worldwide in the assessment of agricultural drought and its severity. This chapter discusses the challenges in identifying a single index to accomplish this task. Given the complexities of drought and its diverse sectoral impacts, this is a formida...

although precipitation is the most important factor which effects rangeland production, but there is little information on the relationship between production and the interactions of climatic factors and specially drought indices. .in this research, the relation between production and climatic factors of rainfall, temperature, evapo- transpiration, and as well as drought indices of standardized...

in order to map the genomic regions affecting barley drought tolerance indices, an experiment was conducted at the agricultural and natural resource station of sistan. seventy tow double haploid lines of barley with their parents (steptoe and morex) were examined using two 9×9 simple lattice (stress and non-stress), with two replications. each plot consisted of six rows that were 3m in length a...

drought stress is one of the most important dangers for increasing the yield and good production of crops in iran and the world. to evaluate the genetic diversity of rapeseed genotypes, identifying the drought resistance indices and drought tolerant genotypes, 16 genotypes were tested in a randomized complete block design (rcbd) with three replications and two different water regimes (irrigated...

Drought stress is one of the most important environmental stresses that have limited the production of wheat, especially in arid and semi-arid regions of the world. To recognize drought tolerant rain-fed wheat genotypes and to determine the best tolerance/susceptibility indices, a study was conducted at the Agricultural Research Station of Miandoab for two cropping years (2013-15). The experime...

The presented paper compares forecast of drought indices based on two different models of artificial neural networks. The first model is based on feedforward multilayer perceptron, sANN, and the second one is the integrated neural network model, hANN. The analyzed drought indices are the standardized precipitation index (SPI) and the standardized precipitation evaporation index (SPEI) and were ...

     Drought monitoring is a fundamental component of drought risk management. It is normally performed using various drought indices that are effectively continuous functions of rainfall and other hydrometeorological variables. In many instances, drought indices are used for monitoring purposes. Geostatistical methods allow the interpolation of spatially referenced data and the prediction of v...