降雪对三江平原小叶章湿地系统氮输入及生态效应

2006年11月至2007年4月,对降雪、地表积雪、积雪融水以及土壤(0～10cm)渗漏液进行野外监测,系统研究了降雪对三江平原小叶章湿地系统氮输入的影响。结果表明,降雪中氮浓度变化明显,其浓度受多种因素影响,降雪中TIN、TON和TN的沉降量分别为0.375、0.591和0.966kg/hm2。地表积雪的氮库主要由地表积雪的总水量决定。积雪融水中TIN以NH₄+-N为主,TN以TON为主;但NO₃--N较NH₄+-N易流失,TIN较TON易流失。土壤(0～10cm)对积雪融水的TIN、TON和TN截留量分别为1.53、0.10和1.63kg/hm2。积雪融水的氮输入促进土壤微生物和植物生长,具有明显的生态效应。

Nitrogen input of snowfall in Deyeuxia angustisfolia wetland system in Sanjiang Plain and its ecological effects

In order to study the effect of nitrogen (N) input of snowfall on the Deyeuxia angustisfolia wetland ecosystem in Sanjiang Plain,the snowfall,snow-pack,snow melting-water and leakage solution of soil (0～10 cm) were monitored from November 2006 to April 2007.The results show that the seasonality of the N concentration in snowfall is evident,and influenced by the manifold factors.The deposition of TIN,TON and TN in snowfall are 0.375,0.591 and 0.966 kg/hm2 in winter,respectively.The snow-pack reservoir determines the N reservoir.The NH₄+-N and TON are the main body of TIN and TN in the snow melting-water,respectively,but the NO₃--N and TIN lose more easily than NH₄+-N,TON,respectively.The interceptions of TIN,TON and TN are 1.53,0.1 and 1.63 kg/hm2 by soil (0～10 cm) respectively.The nitrogen input of snow melting-water has directie ecological signification which stimulates growth of the plant and the microbe in soil.