长江口滨岸湿地无机氮界面交换通量量算

基于3年长江口滨岸湿地沉积物－水界面无机氮季节性交换通量连续实测数据，建立无机氮界面交换通量空间插值模型与量算模型，对无机氮界面交换通量季节性空间分布特征、滨岸湿地不同岸段无机氮季节性界面交换总通量量算等研究。结果表明：修正GIDS插值模型在无机氮界面交换通量空间插值预测过程中精度明显优于IDS方法，而略优于普通Kriging方法;长江口滨岸湿地沉积物－水界面无机氮交换通量空间分布在不同季节表现出复杂的空间分异特征;利用修正GIDS插值模型对长江口滨岸湿地无机氮交换通量进行空间插值过程中，为提高通量量算模型精度，应采用1.2'×1.2'的空间尺度为最佳;长江口滨岸湿地无机氮界面交换总通量量算表明，长江口滨岸湿地在春季向水体释放无机氮，是水体无机氮的释放源，释放量为1.33×10⁴ t，夏季、秋季和冬季表现为净化水体中无机氮，是水体无机氮的吸收汇，分别净化无机氮量为4.36×10⁴ t、6.81×10⁴ t和2.24×10⁴ t，全年总体表现为净化水体中无机氮，净化量为12.1×10⁴ t;长江口多年水体中无机氮通量多项式拟合分析得出，2002~2004年3年长江口水体中无机氮通量平均值为52.6×10⁴ t，滨岸湿地对长江口水体中无机氮的年均净化率达23.0%。

Calculation of Inorganic Nitrogen Fluxes in the Yangtze Estuary Tidal Wetland

Based on the data of inorganic nitrogen fluxes at the sediment-water interface of eleven typical sectional sites in tidal wetland of the Yangtze estuary from 2002 to 2004, we established the inorganic nitrogen fluxes interpolation model and calculating model. Using these models, we studied the spatio-temporal distributing characteristics of inorganic nitrogen fluxes, and calculated the total fluxes in different sectional tidal wetlands and different seasons. The results show: (1) compared to IDS and Ordinary Kriging, the forecast precision of fluxes interpolation is better using revising GIDS interpolation model; (2) the sediment-water exchanges of inorganic nitrogen showed complicated spatial differences and seasonal variations; (3) when using revising GIDS model to interpolate, in order to improve calculating precision of fluxes, the spatial scale should adopt 1.2' ×1.2'; (4) the Yangtze estuary tidal wetland releases inorganic nitrogen fluxes into water in spring, and the releasing quantity is 1.33×10⁴ t. In summer, autumn and winter, Yangtze estuary tidal wetland purifies inorganic nitrogen fluxes from water, and the purifying quantity is 4.36×10⁴ t, 6.81×10⁴ t and 2.24×10⁴ t, separately. All the year round, the Yangtze estuary tidal wetland purifies inorganic nitrogen fluxes from water, tand he purifying quantity is 12.1×10⁴ t; and (5) the purifying ratio is about 23.0%.