Topsoil phosphorus signature in five forest types along an urban-suburban-rural gradient in Nanchang, southern China  

南昌市城-郊-乡梯度五种森林类型表层土壤磷素分布格局(英文)

作　　者：陈伏生[1] 李茜[1] Greg Nagle 詹书侠[1] 

机构地区：[1]南昌大学生命科学学院,江西南昌330031 [2]Cornell大学自然资源系,美国纽约ithaca14853

出　　处：《Journal of Forestry Research》2010年第1期39-44,I0002,共7页林业研究（英文版）

基　　金：funded by the National Natural Science Foundation of China(No.3060047&30960311);Natural Science Foundation of Jiangxi Provinces(No.2007GQN1935)

摘　　要：Conversions from rural to urban land uses have the potential to greatly modify soil phosphorus （P） levels. Soils in shrubs, Masson pine forest, conifer and broadleaf mixed forest, evergreen broadleaved forest and bamboo forest in the mid-subtropical region along an urban-rural gradient in Nanchang City, southern China, were analyzed for total P and P fractions using the modified Hedley P sequential fractionation method. Results show that the topsoil total P and total exactable P concentrations were significantly higher in the urban area （0.71 g·kg^-1 and 378.50 mg·kg^-1, respectively） than in the suburban （0.30 g·kg^-1 and 150.74 mg·kg^-1, respectively） and rural areas （0.31 g·kg^-1 and 147.38 mg·kg^-1, respectively） （p〈0.05）. Among the five P fractions of resin-P, NaHCO3-P NaOH-P, Sonication-P and HCI-P, the relative abundance of HCl-P in urban forest soils （36%） was the highest and also significantly higher than in suburban （8%） and rural soils （6%）, while NaOH-P was the dominant form in suburban （41%） and rural soils （50%）. Phosphorus accumulation in the urban soils could affect the cycle of P in urban forest systems, particularly the HCl-P fraction that might rapidly enrich aquatic systems in urban areas.城市化所改变的土壤利用方式将显著地影响土壤磷素(P)含量水平。本研究沿地处中亚热带地区的南昌市选取灌丛、松林、针阔混交林、常绿阔叶林和毛竹林为研究对象,采用改进Hedley的P素连续分级法分析了土壤全P及各功能P形态的分布规律。结果表明:森林表层土壤全P和可提取态P的含喇均表现为城区(0.71g·kg-1和378.50mg·kg-1)明显高于郊区(0.30g·kg-1和150.74mg·kg-1)和农村(0.31g·kg-1和147.38mg·kg-1)(p<0.05)。在树脂P、NaHCO3-P、NaOH-P、声波P和HCl-P等5种功能P形态中,城区森林土壤HCl-P的相对含度最高,为36%,明显高于其郊区相对含量为8%年农村相对含量为6%的水平。而郊区和农村地区,土壤NaOH-P是其主要的存在形态,其相对含量分别达到41%和50%。可见,城区土壤P积累将影响城市森林生态系统的P循环,且其高含量的HCl-P可能加速P在城区水生系统的富集。图3表2参32。

关 键 词：hilly red soil phosphorus accumulation soil phosphorusfractionation URBANIZATION urban forest 

分 类 号：S714[农业科学—林学] S731.2