Water-holding Capacity of Litter and Soil Under Chinese Fir Forest with Different Densities in Dagangshan Mountain of Jiangxi Province
Hydrological function of litter and soil under Chinese fir forest with various densities was studied in Dagangshan mountain of Jiangxi province, the results showed as the following: (1) With regard to litter depth, amount of litter accumulation, total porosity and maximal soil water-storage, different fir forest had the same sort order like N3500 >N4700 >N2700 >N1700 >N900, however, the order was contrary in term of soil bulk density. (2)Maximum litter water-holding capacity of N3500 was the maximum(12. 60 t/hm2), and the highest water-holding proportion of N1700 was the biggest (254. 98%), however, both maximum water-holding capacity and the highest water-holding proportion of N2700 were the lowest, which were 9. 69 t/hm2 and 229. 07%, respectively. The effective retaining amount of litter in different fir forest ranged from 5. 18 t/hm2 to 6.35 t/hm2, and the order was N3500 >N4700 >N1700 >N900 >N2700. (3) The relationships between water-holding rate and immersion time of whether semi-decomposed or un-decomposed litter in all different fir forests were significantly fitted by Logarithmic equation(Q = aln t + b). The relationships between water absorption speed rate and soaking time were described by power function(V = ktn). (4) Both soil capillary porosity and water storage of N3500 were the highest(40. 04%, 3 153. 16 t/hm2), and the smallest values of both the factors were found in forest stand of N900(38. 56%, 3 059. 76 t/hm2). The soil non-capillary porosity changed from 9.42% to 11. 33%, and a sequence was N4700 > N3500 > N2700 > N900 > Ni700 , while effective water storage showed a order like N3500>N4700>N2700>N900>N1700 , and ranged from 721. 93 t/hm2 to 894. 70 t/hm2. (5)Soil stable infiltration rate of different forests stand ranged from 1. 34 mm/min to 3. 52mm/min. In short, the forest with density about 3 500 tree per hectare showed better water conservation ability than the other forest. Consequently, a reasonable planting density should be taken account of in future forest management in order to perform better in water conservation.
Dagangshan mountainChinese fir forestdifferent densitieshydrological effect
万方数据
