长白山圆池泥炭氮元素分布特征及其影响因素分析

通过对长白山圆池4个泥炭剖面样品的分析,揭示了其氮元素分布规律。在圆池选取4个具有代表性的采样点,利用泥炭采样器采取新鲜泥炭样品。分析结果表明,4个泥炭剖面氮元素含量在0.014%~3.353%之间;剖面间相比较,其中贫营养泥炭整体含氮量较低;4个泥炭剖面的氮元素分布呈现明显规律,受泥炭上层不同植物、泥炭水分和有机质含量等因素的影响,泥炭剖面中氮元素累积峰可能出现在剖面的表层(0~5cm)或中间层(10~20cm);泥炭剖面氮元素与有机质呈极显著的正相关;泥炭剖面C/N比值变化在9.51~66.98之间,部分剖面层位C/N比值异常高,表明该层位碳的累积速度显著高于氮元素。

Characteristics of Nitrogen Distribution and Their Affecting Factors in the Peat Profiles of the Yuanchi in the Changbaishan Mountains

The nitrogen cycle is closely related to the ecological environment. Peat mire has a function as effective reservoirs of nitrogen. As one of the important components of peat mire, nitrogen is an ecological factor of peat mire ecosystems and greatly influences the productivities of peat mire. To study the distribution characteristics of total nitrogen and the effecting factors from the environment is main objective of this paper. The sample sites chosen were located in the Yuanchi in the Changbaishan Mountains. According to different environment conditions, 4 representative profiles were chosen to analyze characteristics of total nitrogen distribution with Wardenaar peat sampler made in Netherlands in the Yuanchi in the Changbaishan Mountains. The samples were cut to 1cm to 2 cm and the top layer of profiles were cut every 1cm, and then cut every 1cm to 2 cm from top to bottom, and cut every 2cm at the bottom layer. The fresh peat samples were used to determine the volume weight, content ash and organic matter content. After air-drying and sieving through a clean 0.15 mm stain -less mesh, the total nitrogen concentrations of the samples were analyzed. The results showed that the range of total nitrogen concentrations in 4 peat profiles were from 0.014 % to 3.353 %. And the total nitrogen concentrations at the same horizontal profiles in Yuanchi-2 and Yuanchi-3 were similar. The total nitrogen concentrations were all lower than 3 % except 3 sites. Compared with other profiles, Yuanchi-4 was oligotrophy peat; therefore its nitrogen concentrations were relatively lower. For the total nitrogen concentrations of top profile, Yuanchi-1 was relatively higher than that of others. The distribution of total nitrogen concentrations for 4 peat profiles was regularly. Due to the effects of the plant, water, organic matter and other environmental factors, the maximum value of total nitrogen concentrations occurred at layer of 0 to 5 cm or 10 to 20 cm. The vertical distribution of total nitrogen in Yuanchi-1 showed that the nitrogen concentrations gradually decreased with depth increase. In Yuanchi-3 and Yuanchi-4 the nitrogen concentrations increased at first then reduced with depth increase. There was close correlation between total nitrogen concentrations and organic matter concentrations in the peat profiles. The range of C/N was from 9.51 to 66.98. The values were relatively higher which indicated that the accumulation rate of C was faster then that of N. On the contrary, the accumulation of C was slowly then that of N.