VARIABILITY AND FORECASTING OF WINTER WHEAT CROP YIELD IN THE SOUTH-WESTERN PART OF THE CENTRAL REGION OF RUSSIA (ON THE EXAMPLE OF BRYANSK REGION)
The interannual tendency of winter wheat crop yield in agro-climatic district of Bryansk region for the period of 1994-2014, which is described by a positive linear trend has been presented in article. The increase in the average annual air temperature by 2.01°C for the period of 1964-2014 has been revealed. Regional manifestations of warming in the Bryansk region are primarily expressed in consistent growth of temperature of the cold period and reduce the amount of rainfall during the growing season of crops and increase frequency and duration of droughts in May and July. The aim of this work is to determine the level of standard of farming and the contribution of the climatic component to the total variance of winter wheat crop yield, using the V.M. Pasov 's model in different soil and climatic conditions of the region. It has been revealed, that the dynamic growth of winter wheat crop yield on the average over the region is caused by the influence of standard of farming (27.1%) and depends on meteorological factors (8.13%), of its productivity formation. The areas where the climatic component of crop yield prevails in the total variance have been marked, and on the territory of the Bryansk region the areas from steady till the most unstable harvests have been allocated. It has been estab ished that in Zhukovsky district with unstable harvest (Cm=0,36), the contribution of the standard of farming to the common crop yield can exceed the weather component. Analysis of the climate component of the variability of yields of winter wheat showed that in the region there is a spatial differentiation of productivity in two agro-climatic regions. The forecasted crop yield of winter wheat grain in the agro-climatic districts of Bryansk region has been defined.