Temperature and rainfall data used to characterize the climate of three ecological areas of the XII Region, Chile.
The most important difference among these areas was the annual amount of rainfall: 255-307 mm, for the Steppe Area; 316-360 mm, for the Brush Area; and 425-515 mm, for the Forest Area.
In all the three areas, rainfall occurs during the 12 manths of the year, but with low intensity; especially in the Steppe Area. During the summer, the hydric restriction is aggravated by the high evapotranspiration, caused bye low relative humidity and high velocity winds.
There are no large differences in temperature among the ecological areas. The principal characteristic is its low value throughout the year. In average, temperatures are about 10ºC, in summer, and 0ºC, in winter.
These temperature and hydric conditions restrict forage production. Estimations of the potential productivity (Loomis and Williams, 1963, modified) give values up to 6,035.9 g/m2 of dry matter per year. The maximun forage (D.M.) productions, determined in the Region, for differente kinds of gransslands, are: 1,140 g/m2, for irrigated alfalfa; 500 g/m2, for lowland meadows; and 60-80 g/m2, for Stepped natural vegetation.