Ayars Jennifer, Gao Yuan
Dresdner Robin, 371 Warren Street, Jersey City, NJ 07302, United States.
Mar Environ Res. 2007 Dec;64(5):590-600. doi: 10.1016/j.marenvres.2007.06.004. Epub 2007 Jul 13.
Measurements of nitrate and ammonium in precipitation and associated with aerosols were conducted at Rutgers University Marine Field Station in Tuckerton, New Jersey from March 2004 to March 2005 to characterize atmospheric nitrogen deposition to the Mullica River-Great Bay Estuary. The arithmetic means of nitrate and ammonium concentrations for precipitation samples were 2.3mgL(-1) and 0.42mgL(-1), respectively. Nitrate and ammonium concentrations in aerosol samples averaged 3.7microgm(-3) and 1.6microgm(-3), respectively. Wet deposition rates appeared to vary with season; the highest rate of inorganic nitrogen deposition (nitrate+ammonium) occurred in the spring with an average value of 1.33kg-Nha(-2)month(-1). On an annual basis, the total (wet and dry) direct atmospheric deposition fluxes into the Mullica River-Great Bay Estuary were 7.08kg-Nha(-2)year(-1) for nitrate and 4.44kg-Nha(-2)year(-1) for ammonium. The total atmospheric inorganic nitrogen directly deposited to the Mullica River-Great Bay Estuary was estimated to be 4.79x10(4)kg-Nyear(-1), and the total atmospheric inorganic nitrogen deposited to the Mullica River watershed was estimated to be 1.69x10(6)kg-Nyear(-1). Only a fraction of the nitrogen deposited on the watershed will actually reach the estuary; most of the nitrogen will be retained in the watershed due to utilization and denitrification during transport. The amount of N reaching the Mullica River-Great Bay Estuary indirectly is estimated to be 5.07x10(4)kg-Nyear(-1), approximately 97% is retained within the watershed. This atmospheric nitrogen deposition may stimulate phytoplankton productivity in the Mullica River-Great Bay ecosystem.
2004年3月至2005年3月期间，在新泽西州塔克顿的罗格斯大学海洋野外站对降水以及与气溶胶相关的硝酸盐和铵进行了测量，以确定大气氮向穆利卡河-大湾河口的沉积特征。降水样品中硝酸盐和铵浓度的算术平均值分别为2.3mgL(-1)和0.42mgL(-1)。气溶胶样品中硝酸盐和铵的浓度平均分别为3.7microgm(-3)和1.6microgm(-3)。湿沉降速率似乎随季节变化；无机氮沉降（硝酸盐+铵）的最高速率出现在春季，平均值为1.33kg-Nha(-2)month(-1)。按年度计算，进入穆利卡河-大湾河口的总（湿和干）直接大气沉降通量，硝酸盐为7.08kg-Nha(-2)year(-1)，铵为4.44kg-Nha(-2)year(-1)。估计直接沉积到穆利卡河-大湾河口的大气无机氮总量为4.79x10(4)kg-Nyear(-1)，沉积到穆利卡河流域的大气无机氮总量估计为1.69x10(6)kg-Nyear(-1)。沉积在流域内的氮只有一小部分会实际到达河口；大部分氮会在运输过程中由于利用和反硝化作用而保留在流域内。估计间接到达穆利卡河-大湾河口的氮量为5.07x10(4)kg-Nyear(-1)，约97%保留在流域内。这种大气氮沉降可能会刺激穆利卡河-大湾生态系统中浮游植物的生产力。
