降雪对三江平原小叶章湿地系统氮输入及生态效应

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

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。

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/hm^2 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/hm^2 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.