Poach M E, Hunt P G, Reddy G B, Stone K C, Matheny T A, Johnson M H, Sadler E J
USDA-ARS, Coastal Plains Soil, Water, and Plant Research Center, 2611 West Lucas Street, Florence, SC 29501, USA.
J Environ Qual. 2004 May-Jun;33(3):844-51. doi: 10.2134/jeq2004.0844.
Ammonia (NH3) volatilization is an undesirable mechanism for the removal of nitrogen (N) from wastewater treatment wetlands. To minimize the potential for NH3 volatilization, it is important to determine how wetland design affects NH3 volatilization. The objective of this research was to determine how the presence of a pond section affects NH3 volatilization from constructed wetlands treating wastewater from a confined swine operation. Wastewater was added at different N loads to six constructed wetlands of the marsh-pond-marsh design that were located in Greensboro, North Carolina, USA. A large enclosure was used to measure NH3 volatilization from the marsh and pond sections of each wetland in July and August of 2001. Ammonia volatilized from marsh and pond sections at rates ranging from 5 to 102 mg NH3-N m(-2) h(-1). Pond sections exhibited a significantly greater increase in the rate of NH3 volatilization (p < 0.0001) than did either marsh section as N load increased. At N loads greater than 15 kg ha(-1) d(-1), NH3 volatilization accounted for 23 to 36% of the N load. Furthermore, NH3 volatilization was the dominant (54-79%) N removal mechanism at N loads greater than 15 kg ha(-1) d(-1). Without the pond sections, NH3 volatilization would have been a minor contributor (less than 12%) to the N balance of these wetlands. To minimize NH3 volatilization, continuous marsh systems should be preferred over marsh-pond-marsh systems for the treatment of wastewater from confined animal operations.
氨（NH₃）挥发是从废水处理湿地中去除氮（N）的一种不良机制。为了尽量减少氨挥发的可能性，确定湿地设计如何影响氨挥发很重要。本研究的目的是确定池塘部分的存在如何影响处理集约化养猪场废水的人工湿地中的氨挥发。将不同氮负荷的废水添加到位于美国北卡罗来纳州格林斯伯勒的六个具有沼泽 - 池塘 - 沼泽设计的人工湿地中。2001年7月和8月，使用一个大型围栏来测量每个湿地的沼泽和池塘部分的氨挥发情况。从沼泽和池塘部分挥发的氨速率范围为5至102毫克NH₃ - N·米⁻²·小时⁻¹。随着氮负荷增加，池塘部分的氨挥发速率增加幅度明显大于任何一个沼泽部分（p < 0.0001）。当氮负荷大于15千克·公顷⁻¹·天⁻¹时，氨挥发占氮负荷的23%至36%。此外，在氮负荷大于15千克·公顷⁻¹·天⁻¹时，氨挥发是主要的（54% - 79%）氮去除机制。如果没有池塘部分，氨挥发对这些湿地的氮平衡贡献将很小（小于12%）。为了尽量减少氨挥发，对于处理集约化养殖场废水，连续沼泽系统应优于沼泽 - 池塘 - 沼泽系统。
