Temperature in the Dongzhiyuan region has increased remarkably since 1990s

with the linear trend being 0.099 5 ℃/a.In terms of warming amplitudes and significance decreased

spring

winter

summer

and autumn were ranked in descending order.Annual precipitation varied like a V-type parabola.The middle and late 1990s was a dry period

especially in spring and autumn. The wet year and dry year changed with a cycle of about two years from 1998.Due to the increase in temperature and decrease in precipitation

soil moisture in winter wheat fields was reduced year by year during the growing season in spring.Soil moisture in tillage layer was reduced consistently year by year in early spring and soil moisture within 30 cm soil layer

in the period of late spring and early summer.Besides

soil moisture changed with precipitation amount in other periods.Although the inter-annual variation of soil moisture was different in different time

soil moisture in winter wheat fields varied like V-type parabola in each year.Soil water content was decreased to the lowest in June

which is the mature period of winter wheat

and then it was gradually increased in autumn.However

soil moisture changed as a linear trend in 1998 and 1999.Agricultural production is affected by soil water conditions(surplus or deficit) which are affected by climate change again.Results from the study also show that agricultural production changes with soil moisture conditions.