摘要
Nitrogen(N)is one of the most important components and ecological factors for natural wetland ecosystems.It is mainly derived from runoff input,atmospheric deposition,and biological N fixation.The transport and transformation of N in natural wetlands primarily occur in the hyporheic zone(HZ),a buffer area of intensified biogeochemical activity that is often regarded as the sink,source,and converter of N in wetlands.The main ways of N attenuation in the HZ are denitrification,anaerobic ammonia oxidation(anammox),and wetland plant adsorption.The effects of internal and human factors on the N cycle are illustrated in this article.The results indicate that N sources are influenced by human factors such as agricultural activities and fossil combustion,while N attenuation is affected by internal factors,including oxygen concentration,carbon and phosphorus availability,pH and Eh changes,and microorganism actions.Finally,some research trends are provided to get a better understanding of the N cycle in the HZ of natural wetlands.This study may provide a clear perspective of N cycle in the HZ and their interactions between various factors.
Nitrogen (N) is one of the most important components and ecological factors for natural wetland ecosystems. It is mainly derived from runoff input, atmospheric deposition, and biological N fixation. The transport and transformation of N in natural wetlands primarily occur in the hyporheic zone (HZ), a buffer area of intensifted biogeochemical activity that is often regarded as the sink, source, and converter of N in wetlands. The main ways of N attenuation in the HZ are denitrification, anaerobic ammonia oxidation (anammox), and wetland plant adsorption. The effects of internal and human factors on the N cycle are illustrated in this article. The results indicate that N sources are influenced by human factors such as agricultural activities and fossil combustion, while N attenuation is affected by internal factors, including oxygen concentration, carbon and phosphorus availability, pH and Eh changes, and microorganism actions. Finally, some research trends are provided to get a better understanding of the N cycle in the HZ of natural wetlands. This study may provide a clear perspective of N cycle in the HZ and their interactions between various factors.
基金
supported by the National Natural Science Fund of China (41272249)
the Research Fund for the Doctoral Program of Higher Education of China (20110072110020)