Assessment of heat supply of vegetation period within the northern grain-seeding territory of Kazakhstan

Abstract

Introduction. The existing agroclimatic handbooks in Kazakhstan are outdated both in informational and technological senses. Therefore necessity of agroclimatic resources reassessment arose.
 Purpose. Research of heat supply of vegetation period within the Northern grain-seeding territory of Kazakhstan.
 Methods. Data of meteorological stations for period of 1981-2014 were used. Methods of statistic and climatologic processing of data were applied. The agroclimatic maps were drafted using ArcGIS 10.1 software.
 Results. The article describes a thermal regime, duration and heat supply of vegetation period within the territory of 4 northern oblasts of Kazakhstan. The territory of Northern Kazakhstan under study hascontinental climate. Average annual air temperature at the area under study increases from the North to the South from 1.8 °C to 5.3 °C. Average July air temperature at the area changes from 18.5 °C to 23.6 °C and average January air temperature – from minus 12.8 °C to minus 17.4 °C. Duration of vegetation period for early spring crops constitutes 172-193 days, for late spring crops – 136-162 days and for warm weather crops – 89-124 days. Daily range of air temperature is 11.4-14.7 °C and that means rather high quality of grain. Sum of active temperatures exceeding 10 °C increases from the North to the South from 2100 °C to 3400 °C. Vegetation period is 90% provided by sum of active temperatures exceeding 10 °C within the range of 2000-2900 °C. Maps of heat supply and vegetation period duration were also drafted.
 Conclusions. In the north of the territory under study thermal sources satisfy demands of soft and common sorts of wheat but are not enough for sunflower and maize, in the south they are enough for wheat, all sorts of sunflower and middle-late sorts of maize.