摘要
对安徽老山自然保护区亚热带常绿阔叶林降雨中可溶性碳和氮动态进行了研究。结果表明,该地区大气降雨pH为6.82,呈中性;TOC含量为3.330mg/L,NH4+-N含量为0.405mg/L,NO3-N含量0.501mg/L。降雨经过冠层后,物质成分的含量发生显著改变。穿透雨的TOC含量为10.498mg/L,NH4+-N含量为0.454mg/L,NO3-N含量为0.959mg/L,分别是林外降雨的3.15,1.12,1.91倍。树干径流的TOC含量为21.157mg/L,NH4+-N含量为0.972mg/L,NO3-N含量为1.040mg/L,分别是林外降雨的6.35,2.40,2.08倍。TOC及氮含量的低值都是出现在夏季生长旺盛期,可能与树木在此期需要大量的养分来维持有关,而林外雨各物质含量的出现低值主要与降雨强度、降雨量有关。
In nutrient cycling study,a growing attention has been paid to TOC and DON in forest ecosystems,particularly focusing on the soil-vegetation-atmosphere interaction.There was little information on the transportation of TOC and DON during the hydrological processes in forest ecosystems.In this study,the seasonal dynamic patterns of TOC and DON were investigated in a subtropical evergreen broad-leaved forest over one year in Laoshan Natural Reserve,south Anhui.The results showed that the concentrations of TOC,NH4^＋-N,NO3^--N were significantly increased after rain passed through forest canopies.The mean concentration of TOC,NH4^＋-N,NO3^--N were,respectively,3.330,0.405,0.501 mg/L for the bulk precipitation;10.498,0.454,0.959 mg/L for the throughfall and 21.157,0.972,1.040 mg/L for the stemflow.No clear monthly variation in TOC concentration was found in throughfall and stemflow.However,DON concentration tended to be lower during high precipitation months,particularly during July and August.TOC concentration in the hydrological processes fluctuated with pH of rainwater intensively.
出处
《水土保持学报》
CSCD
北大核心
2010年第2期146-149,164,共5页
Journal of Soil and Water Conservation
基金
国家自然科学基金资助项目(30471386
30771719)
关键词
森林水文
可溶性有机碳
可溶性氮
穿透雨
树干径流
forest hydrology
dissolved organic carbon
dissolved nitrogen
throughfall
stemflow
