Impacts of climatic change on potato growth in the semi-humid region over extra-tropical and cool Northwest of China: a case study in Minxian County of Gansu Province
Abstract:Using potato growth and meteorological condition observational data in the cool and semi-humid region over northwest China to analyze the effects on potato growth of climatic change and the relationship between potato growth and meteorological condition. The results show that precipitation displays a descending trend, and it changes in a velocity of -8.329mm/10a change and an annual period change of 3a. It is proved that the temperature displays a marked ascending trend and changes in a velocity of 0.144℃/10a. It is also proved that the aridity index displays an ascending trend during the crop growth period, it changes in a velocity of 0.042/10a, and the tendency is significant from the beginning of 1990 to 2007 year. It is showed that potato needs 150-168d, about 2000-2300℃ accumulated temperature above 0℃, about 400-500mm precipitation and about 900-1100h sunshine duration from sowing to reaping. It is also showed that potato tuber growing velocity turns to higher at the 105d after sowing and becomes lower at the 149d after sowing. The time of the highest velocity is the 127d after sowing. The inflorescence forming period is ahead for (8-9)d/10a and the florescence period is ahead for (4-5)d/10a because of the warming climate. Except for that in the reaping period, the temperature is negative to the yield, and it is sensitive to the temperature during the tuber expansion period. The influences of precipitation and temperature are distributed in an in-phase opposition. Except for that in the seedling and reap periods, precipitation is positive to the yield, and it is sensitive to precipitation from the bifurcation period to the florescence period.