State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, No. 19 Xinjiekouwai Street, Beijing, 100875, People's Republic of China.
Environ Monit Assess. 2012 Mar;184(3):1253-63. doi: 10.1007/s10661-011-2037-3. Epub 2011 Apr 15.
Horizontal and profile distributions of nitrogen in marsh soils in different seasons were studied in a typical site within the Erbaifangzi wetland in Northeast China. Results showed that there was higher spatial heterogeneity for nitrate nitrogen (NO[Formula: see text]N) and ammonium nitrogen (NH[Formula: see text]-N), as well as available nitrogen (AN), in surface soils in July compared to that in September. Relative to July, the mean nitrogen contents in surface soils were slightly higher in September; however, in November, soils contained significantly lower NO[Formula: see text]N and NH[Formula: see text]-N, higher AN, organic nitrogen (Org-N), and total nitrogen (TN). Except for mineral nitrogen, no significant differences were observed between Org-N and TN contents in September and November. Nitrogen contents generally declined exponentially with depth along soil profiles in three sampling dates (July, September, and November), except for a significant accumulation peak of NO[Formula: see text]N at the 20-30 cm depth in September. However, NH[Formula: see text]-N contents showed a vertical alternation of "increasing and decreasing" in both July and September, while nearly kept constant with depth in November. The depth ranking of nitrogen showed the shallowest distribution for AN, followed by Org-N and TN, while deeper distributions for NO[Formula: see text]N and NH[Formula: see text]-N. TN, Org-N, and AN were significantly correlated with soil organic matter and total phosphorus. Soil pH values were significantly correlated with TN and AN contents in surface soils. Clay contents showed significant correlations with nitrogen contents except for NO[Formula: see text]N in surface soils and NH[Formula: see text]-N in profile soils. However, soil moisture was not significantly correlated with nitrogen contents among all soil samples.
本研究以中国东北二方院子湿地为典型样地，研究了不同季节湿地土壤氮的水平和剖面分布。结果表明，7 月份表层土壤硝态氮（NO[Formula: see text]N）、铵态氮（NH[Formula: see text]-N）和有效氮（AN）的空间异质性明显高于 9 月份。与 7 月相比，9 月表层土壤氮含量略高，但 11 月土壤中 NO[Formula: see text]N 和 NH[Formula: see text]-N 明显降低，AN、有机氮（Org-N）和全氮（TN）升高。9 月和 11 月 Org-N 和 TN 含量无显著差异，除矿质氮外。在三个采样日期（7 月、9 月和 11 月），除 9 月 20-30cm 深度处有明显的硝态氮积累峰外，土壤剖面中氮含量随深度呈指数下降。然而，7 月和 9 月 NH[Formula: see text]-N 含量呈“增减”交替的垂直变化，而 11 月则几乎保持不变。氮的深度分布表现为 AN 分布最浅，其次是 Org-N 和 TN，而 NO[Formula: see text]N 和 NH[Formula: see text]-N 分布较深。TN、Org-N 和 AN 与土壤有机质和总磷显著相关。表层土壤的 pH 值与 TN 和 AN 含量显著相关。除表层土壤中 NO[Formula: see text]N 和剖面土壤中 NH[Formula: see text]-N 外，粘粒含量与氮含量呈显著相关，但土壤水分在所有土壤样品中与氮含量无显著相关性。
