Atmospheric Input of Nutrients and Dust to the SE Mediterranean
Atmospheric Input of Nutrients and Dust to the SE Mediterranean
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DOI：
10.1007/978-94-017-3354-0_35
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发表时间：
1996
期刊：
影响因子：
--
通讯作者：
B. Herut;M. Krom
中科院分区：
文献类型：
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作者：
B. Herut;M. Krom
对地中海北部以色列海岸(Haifa)3个冬季采集的84个雨水样本中溶解营养物(PO4、NO3、NH4和Si(OH)4)的浓度和pH值进行了监测。主要的溶解无机氮(DIN)化合物是硝酸盐，浓度在4.2300μM之间，在60次事件中只有12次以铵为主，其浓度在2.2μM到96.9μM之间，磷酸盐的浓度范围在0.09到8.8μM之间，只有在相对碱性的降雨(pH和gt；6)才能检测到较高的硅酸浓度(>；2 gt；M)，这可能是因为在更碱性的条件下，石英和粘土颗粒在雨水中的溶解程度更大。虽然大约30%的降雨被认为是酸雨，但它们的主要H+供体是非海绵硫酸盐，而不是硝酸盐。硝酸盐和磷酸盐具有相似的时间变异性，表明它们是大多数降雨事件的共同来源。雨水中的N/P比(中位数为80：1)高于莱昂特水域(~27：1)，而以色列地中海沿岸的河流出口的N/P比较低，这表明大气中的营养物质可能在决定东地中海异常高的N/P比中起重要作用。测得的降雨N通量和计算的进入东南地中海的总(湿+干)N通量分别为0.3g N m−2yr−1。这些数值略低于之前在地中海西部测得的通量，这可能是由于来自欧洲北部的人为输入减少所致。地中海东南部上空的总悬浮粒子(TSP)浓度(称为尘埃)约为以色列地中海中部和北部沿岸记录的浓度的一半。估计流入沿海和地中海东南部的气溶胶通量分别为72和36g m−2yr−1。根据后者计算的地中海东南部的干P通量约为0.0139 g P m−2yr−1。
Concentrations of dissolved nutrients (PO4, NO3, NH4and Si(OH)4) and pH have been monitored in 84 rain water samples collected during 3 winters at the northern Mediterranean Israeli coast (Haifa). The main dissolved inorganic nitrogen (DIN) compound was nitrate, with concentrations between 4.2 and 300 μM. Ammonium was dominant only in 12 out of 60 events, and its concentrations ranged between 2.2 and 96.9 μM. Phosphate showed a range of concentrations between 0.09 and 8.8 μM. High silicic acid concentrations (>2 μM) were detected only during relatively basic rains (pH>6), probably due to greater dissolution of quartz and clay particles into rain water under more basic conditions. Although about 30% of the rains are considered to be acid rains, their main H+donor is non-seaspray sulfate and not nitrate. Nitrate and phosphate showed similar temporal variability, suggesting their common origin for most of the rain events.N/P ratios in rainwater (median of 80:1) were higher than in Levantine Waters (~27:1), while those of the river outlets along the Israeli Mediterranean coast were found to be lower, suggesting that atmospheric derived nutrients may be important in determining the abnormally high ratios in the eastern Mediterranean.The measured N flux in rainfall and the calculated total (wet + dry) N flux to the SE Mediterranean are 0.3 and 0.377 g N m−2yr−1, respectively. These values are somewhat lower than fluxes determined previously in the western Mediterranean, probably due to reduced anthropogenic inputs from N. Europe.Total suspended particles (TSP) concentrations (referred to as dust) over the SE Mediterranean Sea were about half the concentrations recorded at the central and northern Israeli Mediterranean coast. The estimated aerosol fluxes into the coastal and the SE Mediterranean Sea were 72 and 36 g m−2yr−1, respectively. Based on the latter, the calculated dry P flux to the SE Mediterranean Sea is about 0.0139 g P m−2yr−1.