大气氮沉降是除河流输入外水库水体重要的外源氮输入途径。以丹江口水库淅川库区为研究区,于2018年11月至2019年10月在库区周边设置了6个采样点,采集并分析了库区大气氮湿沉降样品,探讨氮湿沉降的时空分布特征以及对水库水体外源氮输入...大气氮沉降是除河流输入外水库水体重要的外源氮输入途径。以丹江口水库淅川库区为研究区,于2018年11月至2019年10月在库区周边设置了6个采样点,采集并分析了库区大气氮湿沉降样品,探讨氮湿沉降的时空分布特征以及对水库水体外源氮输入的贡献。研究结果表明,研究区大气氮湿沉降量为24.21 kg hm^(-2)a^(-1),其中氨氮占比(47.45%)为最大,有机氮占比(36.34%)次之,硝氮占比(16.21%)最小。硝氮湿沉降量在空间上表现出显著差异性。氨氮、有机氮湿沉降量的季节差异显著,氨氮是以夏季最高,秋季次之,冬季最低,而有机氮是以秋季最高,夏季次之,冬季最低。氨氮、硝氮、有机氮湿沉降量之间存在显著相关性,氨氮、有机氮湿沉降量与降水量之间存在显著相关性。总氮、氨氮湿沉降量分别为1321.98 t/a和627.34 t/a,分别占河流总氮、氨氮入库量的10.82%、34.85%。研究结果可为探索有针对性的库区水体氮污染控制途径提供重要理论基础。展开更多
Riparian wetland is the major transition zone of matter, energy and information transfer between aquatic and terrestrial ecosystems and has important functions of water purification and non-point pollution control. Us...Riparian wetland is the major transition zone of matter, energy and information transfer between aquatic and terrestrial ecosystems and has important functions of water purification and non-point pollution control. Using the field experiment method and an isotope tracing technique, the agricultural non-point nitrogen pollution control function of different vegetation types in riparian wetland was studied in the Kouma Section of the Yellow River. The results showed that the retention of agricultural non-point nitrogen pollution by riparian wetland soil occurs mainly in top 0-10 cm layer. The amount of nitrogen retained by surface soils associated with three types of vegetation are 0.045 mg/g for Phragmites communis Trin Linn, 0.036 mg/g for Scirpus triqueter Linn, and 0.032 mg/g for Typha angustifolia Linn, which account for 59.21%, 56.25%, and 56.14% of the total nitrogen interception, respectively. Exogenous nitrogen in 0-10 cm soil layer changes more quickly than in other layers. One month after adding KISNO3 to the tested vegetation, nitrogen content was 77.78% for P communis Trin, 68.75% for T. angustifolia, and 8.33% for S. triqueter in the surface soil. After three months, nitrogen content was 93.33% for P. communis Trin, 72.22% for S. triqueter, and 37.50% for T. Angustifolia. There are large differences among vegetation communities respecting to purification of agricultural non-point nitrogen pollution. The nitrogen uptake amount decreases in the sequence： new shoots ofP. communis Trin （9.731 nag/g） 〉 old P. communis Trin （4.939 mg/g） 〉 S. triqueter （0.620 mg/g） 〉 T. angustifolia （0.186 mg/g）. Observations indicated that the presence of riparian wetlands as buffers on and adjacent to stream banks could be recommended to control agricultural non-point pollution.展开更多
文摘大气氮沉降是除河流输入外水库水体重要的外源氮输入途径。以丹江口水库淅川库区为研究区,于2018年11月至2019年10月在库区周边设置了6个采样点,采集并分析了库区大气氮湿沉降样品,探讨氮湿沉降的时空分布特征以及对水库水体外源氮输入的贡献。研究结果表明,研究区大气氮湿沉降量为24.21 kg hm^(-2)a^(-1),其中氨氮占比(47.45%)为最大,有机氮占比(36.34%)次之,硝氮占比(16.21%)最小。硝氮湿沉降量在空间上表现出显著差异性。氨氮、有机氮湿沉降量的季节差异显著,氨氮是以夏季最高,秋季次之,冬季最低,而有机氮是以秋季最高,夏季次之,冬季最低。氨氮、硝氮、有机氮湿沉降量之间存在显著相关性,氨氮、有机氮湿沉降量与降水量之间存在显著相关性。总氮、氨氮湿沉降量分别为1321.98 t/a和627.34 t/a,分别占河流总氮、氨氮入库量的10.82%、34.85%。研究结果可为探索有针对性的库区水体氮污染控制途径提供重要理论基础。
基金supported by the National Natural Sci- ence Foundation of China (No. 30570276)
文摘Riparian wetland is the major transition zone of matter, energy and information transfer between aquatic and terrestrial ecosystems and has important functions of water purification and non-point pollution control. Using the field experiment method and an isotope tracing technique, the agricultural non-point nitrogen pollution control function of different vegetation types in riparian wetland was studied in the Kouma Section of the Yellow River. The results showed that the retention of agricultural non-point nitrogen pollution by riparian wetland soil occurs mainly in top 0-10 cm layer. The amount of nitrogen retained by surface soils associated with three types of vegetation are 0.045 mg/g for Phragmites communis Trin Linn, 0.036 mg/g for Scirpus triqueter Linn, and 0.032 mg/g for Typha angustifolia Linn, which account for 59.21%, 56.25%, and 56.14% of the total nitrogen interception, respectively. Exogenous nitrogen in 0-10 cm soil layer changes more quickly than in other layers. One month after adding KISNO3 to the tested vegetation, nitrogen content was 77.78% for P communis Trin, 68.75% for T. angustifolia, and 8.33% for S. triqueter in the surface soil. After three months, nitrogen content was 93.33% for P. communis Trin, 72.22% for S. triqueter, and 37.50% for T. Angustifolia. There are large differences among vegetation communities respecting to purification of agricultural non-point nitrogen pollution. The nitrogen uptake amount decreases in the sequence： new shoots ofP. communis Trin （9.731 nag/g） 〉 old P. communis Trin （4.939 mg/g） 〉 S. triqueter （0.620 mg/g） 〉 T. angustifolia （0.186 mg/g）. Observations indicated that the presence of riparian wetlands as buffers on and adjacent to stream banks could be recommended to control agricultural non-point pollution.
