Abstract:

To reveal the temporal and spatial variation characteristics of precipitation in forage growing season and the relationship between precipitation and natural forage growth, and between precipitation and drought and flood in Guoluo of Qinghai, we used a method which is advanced and simple to conduct the study. The results showed that: (1) the main precipitation periods in Guoluo were divided into 1961-1969, 1970-1979, 1980-1991 and after 1992; from the perspective of space, the precipitation showed an obviously decreasing trend from southeast to northwest, the maximum precipitation amount was in Jiuzhi and the minimum was in Maduo; the maximum precipitation amount was 2.3 times of the minimum; and the precipitation in the central areas of Guoluo was close to the average value of the maximum and the minimum; (2) there was a significantly positive correlation between forage yield and average temperature and precipitation, and a significantly negative correlation between forage yield and sunshine hours; (3) the stage significantly higher than the PCD (precipitation concentrated degree) trend line coincided with the high-frequency period of rainstorm and flood, and the stage significantly higher than the PCP trend line coincided with the high-frequency period of drought.

Key words: forage growing season, precipitation concentration degree, precipitation concentration period, correlation