Producción de Hojarasca y sus Relaciones con Factores Meteorológico en un Bosque de Pinus radiata (D.Don.)

Abstract

Weekly, monthly an annua l fluctuations of litterfall were investigated in a 26-yr forest of Pinus radiata. The relationships between litterfall and precipitation, air temperatur e and wind velocity were studied. The study area is located in Huape Tres Esteros, 20 km nort h from Valdivia (Lat. 39°48'S , Long. 73°14'W). Litterfall was recorded betwee n January , 198 1 and April, 1983 , using l8 traps of 0.5 x 0.5 m (surface = 0.25 m2 ) The litter was divided into needles, flowers, seeds and others (branches, bark).
Litter productio n (dry weight) in 198 1 and 1982 was 369. 8 and 413. 1 g/m2 , respectively; needles contribute d 86.7 and 79.5°/ o respectively, to the litter produc ­ tion. Flowers participated with only 6.6 and 7.1% , to the tota l weight, while the contributions of branche s and barks, amounte d to 6.4 and 13.0 % , respectively. Seeds with 0.3 and 0.4 % the smallest fraction of the litter produce d in 198 1 and 1982 respectively.
The fall of needles, branche s and barks is directly determined by the maximum wind velocity. Litterfall increases considerably with wind velocities higher than 20m/sec . Litter from the flowers was found in Septembe r and October. The seed production , apart from showing a marke d annua l rhythm, is directly correlated with the weekly mean maximum air temperature .