Zhang B.,Fujian Province Key Laboratory of Humid Subtropical Eco Geographical Process |
Zhang B.,Fujian Normal University |
Gao R.,Fujian Province Key Laboratory of Humid Subtropical Eco Geographical Process |
Gao R.,Fujian Normal University |
And 6 more authors.
Chinese Journal of Applied Ecology | Year: 2010
An investigation was made on the soil soluble organic nitrogen (SON) in two natural forests Altingia gracilies (ALG) and Castanopsis carlesii (CAC) and an adjacent 35 -year-old Cunninghamia lanceolata (CUL) plantation in Wanmulin Nature Reserve in Jianou, Fujian Province. Among the three forest stands, ALG had a significantly higher content of soil SON, being 95. 3, 78.3, and 72. 5 mg • kg-1 in 0-5 cm, 5-10 cm, and 10-20 cm soil layers, respectively (P< 0. 05) ,'while CAC and CUL had lesser differences in their soil SON content, which was 74. 5, 70. 1, and 65. 6 mg • kg-1 in the three soil layers for CAC, and 78. 6, 68. 9, and 69. 1 mg • kg -1 in the three soil layers for CUL, respectively. The proportion of SON to total soluble nitrogen (TSN) in 0-20 cm soil layer was 79. 17-80. 78% for CAC, 68. 64% -74. 51% for CUL, and 59. 97% -69. 66% for ALG. With increasing soil depth, the proportion of soil SON to soil TSN and total nitrogen (TN) for the three forest stands all increased. Soil SON content had a significant positive correlation with soil organic carbon (r=0. 982 , P<0. 01) , and also, had definite correlations with soil TSN, TN, NH+ 4 -N, and NO- 3-N. It also correlated with the factors such as forest type, topography, altitude, and tree age.