title: Available phosphorus in forest soil increases with soil nitrogen but not total phosphorus: evidence from subtropical forests and a pot experiment.
abstract: This paper aims to establish evidence for available phosphorous (AP) binding with total nitrogen (N) in subtropical forest soils. Soil organic carbon (SOC), total N, total phosphorous (P) and AP concentration were measured for three contrasting forest types in southern China: Masson pine forest (MPF), coniferous and broadleaved mixed forest (CBMF) and monsoon evergreen broadleaved forest (MEBF). A pot experiment with N addition was conducted to confirm the dominant factor to affect on soil AP concentration. The results showed that mean soil total N concentration in 0-10 cm soil layer was 440 ± 50 for MPF, 840 ± 80 for CBMF and 1020 ± 50 mg kg(-1) for MEBF, respectively. The mean soil AP concentration in 0-10 cm soil layer was 2.67 ± 0.87 for MPF, 2.65 ± 0.58 for CBMF, 4.10 ± 0.29 mg kg(-1) for MEBF, respectively. The soil total N concentration could explain about 70% of the variations in soil AP concentration in the top 20 cm soil layers in the three forest types. A pot experiment with N addition also showed an increase of AP concentration from 2.56 to 5.63 mg kg(-1), when N addition increased from 5 g to 17 g NH4NO3. Our results therefore suggested that N addition significantly increased soil AP concentration, which might be beneficial for stabilizing the net primary production of subtropical forests that were limited by soil AP. This finding may provide a theory basis for tropical and subtropical forests management.
authors: South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China.
authors: Xingzhao
authors: X
authors: Liu
authors: Paulownia Research and Development Centre, China Forestry Administration, Zhengzhou, China.
authors: Wei
authors: W
authors: Meng
authors: State Key Laboratory of Conservation and Utilization of Subtropical Agro-Bioresources, South China Agricultural University, Guangzhou, China.
authors: Guohua
authors: G
authors: Liang
authors: South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China.
authors: Kun
authors: K
authors: Li
authors: South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China.
authors: Weiqiang
authors: W
authors: Xu
authors: Guangdong Provincial Academy of Environmental Science, Guangzhou, China.
authors: Liujing
authors: L
authors: Huang
authors: South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China.
authors: Junhua
authors: J
authors: Yan
mesh_terms: D002244:Carbon / Q000737:chemistry; D002681:China; D009584:Nitrogen / Q000737:chemistry*; D010758:Phosphorus / Q000737:chemistry*; D012987:Soil / Q000737:chemistry*; D014197:Trees / Q000737:chemistry*; D014329:Tropical Climate
chemical_list: D012987:Soil; D010758:Phosphorus; D002244:Carbon; D009584:Nitrogen