Water-holding Characteristics of Typical Forests Types Litter in the Upper and Middle Reaches of Dongjiang Watershed

Hydrological functions of main forest litters were assessed by measuring and analyzing the litter amount,the water holding capacity,and the processes with methods of field survey and soaking extraction experiment in the upper and middle reaches of Dongjiang watershed.The result showed the litter amount ranged from 4.76 t/hm2 to 12.13 t/hm2,with a decrease order of conifer-broadleaf mixed forest,followed by Cunninghamia lanceolata forest,broadleaf mixed forest,Pinus massoniana forest,and brushwood respectively.The maximum water-holding volume of different forests litters ranged from 4.89 t/hm2 to 18.17 t/hm2 with the highest value in the Cunninghamia lanceolata forest,followed by conifer-broadleaf mixed forest,broadleaf mixed forest,brushwood,and Pinus massoniana forest.The mixed interception amount and the effective interception amount showed similar trends with values from 3.34 t/hm2 to 14.39 t/hm2,and 2.60 t/hm2 to 11.66 t/hm2 respectively.We found that the water-holding rate increased logarithmically with soaking time,while the water-absorption rate showed an inverse function with soaking time.The dynamic changes of the water-holding rate and the water-absorption rate were generally similar of different forests litters.The water-holding rates of litters increased with prolong of soaking time,and leveled off after 10 hours to 12 hours.The water-absorption rates decreased sharply during the first 2 hours,then decreased gradually,and fell to zero after 24 hours.

Ҳали таржима қилинмаган