Many-years changes of yield and «yield waves» in Poltava region

Abstract

The paper deals with research of many-years
changes of crop yield in Poltava region. Analysis of
crop yield changes is carried out at the research
period from 1966 to 2012 including. Average graph
curves of crop yield are presented. Three periods of
crop yield changes with two evident minimum of
yield are found out. Average period of «yield wave»
for all of crops is given. The role of
geliogeophysical factors and moon-earth influences
in formation and changes of crop yield is also
analyzed.