The two factors of drought conditions and export markets are focusing recent attention on nitrates and prussic acid in forages. During normal years, nitrate-nitrogen (NO3-N) taken up by crops is quickly converted into protein. When forages grow under drought stress, however, they tend to accumulate nitrate. Alternative forages such as sorghums and sudans tend to accumulate even higher levels, w...

Aim Fire suppression, elk (Cervus elaphus Erxleben) browsing and drought have been suggested as possible explanations for low aspen (Populus tremuloides Michx.) ramet regeneration in elk winter range of the Greater Yellowstone Area (GYA) during the twentieth century. This study analyses the relationship between the rates of aspen regeneration, biophysical factors and human land use since 1830. ...

Extreme droughts and heat waves due to climate change may have permanent consequences on soil quality and functioning in agroecosystems. During November 2010 to August 2011, the Southern High Plains (SHP) region of Texas, U.S., a large cotton producing area, received only 39.6 mm of precipitation (vs. the historical avg. of 373 mm) and experienced the hottest summer since record keeping began i...

the main purpose of this study was to analyze the causes, impacts and mechanisms of drought crisis management in rural and nomadic communities in iran. 201 experts and managers involved in drought crisis management were surveyed through a complete enumeration/census. face validity and content validity of the questionnaire were confirmed by experts. the calculated cronbach’s alpha for the differ...

We present MOWCATL, an efficient method for mining frequent sequential association rules from multiple sequential data sets with a time lag between the occurrence of an antecedent sequence and the corresponding consequent sequence. This approach finds patterns in one or more sequences that precede the occurrence of patterns in other sequences, with respect to user-specified constraints. In addi...

Increases in the frequency, duration, and severity of regional drought pose major threats to the health and integrity of downstream ecosystems. During 2007-2008, the U.S. southeast experienced one of the most severe droughts on record. Drought and water withdrawals in the upstream watershed led to decreased freshwater input to Apalachicola Bay, Florida, an estuary that is home to a diversity of...

introduction: drought is a creeping natural phenomenon, which can occur in any region. such phenomenon not only affects the region subjected to drought, but its adverse effects can also be extended to other adjacent regions. this phenomenon mainly starts with water deficiency (say less than long- term mean of variable under study such as rainfall, streamflow, groundwater level or soil moisture)...