Science. 1990 Nov 2;250(4981):661-4. doi: 10.1126/science.250.4981.661.
Photochemical production rates and steady-state concentrations of hydroxyl radicals (.OH) were measured in sunlight-irradiated seawater. Values ranged from 110 nanomolar per hour and 12 x 10(-18) molar in coastal surface water to 10 nanomolar per hour and 1.1 x 10(-18) molar in open ocean surface water. The wavelengths responsible for this production are in the ultraviolet B region (280 to 320 nanometers) of the solar spectrum. Dissolved organic matter (DOM) appears to be the main source for .OH over most of the oceans, but in upwelling areas nitrite and nitrate photolysis may also be important. DOM in the deep sea is degraded more readily by .OH (and its daughter radicals), by a factor of 6 to 15, than is DOM in open-ocean surface water. This finding may in part bear on major discrepancies among current methods for measuring dissolved organic carbon in seawater.
在阳光照射的海水中测量了光化学产生速率和羟基自由基（.OH）的稳态浓度。在近岸表层水中，其范围从每小时 110 纳摩尔至 1.2×10^(-18) 摩尔，在开阔海洋表层水中，其范围从每小时 10 纳摩尔至 1.1×10^(-18) 摩尔。产生这种物质的波长在太阳光谱的紫外线 B 区域（280 至 320 纳米）内。在大多数海洋中，溶解有机物（DOM）似乎是.OH 的主要来源，但在上升流区域，亚硝酸盐和硝酸盐的光解也可能很重要。深海中的 DOM 比开阔海洋表层水中的 DOM 更容易被.OH（及其子自由基）降解，降解速率快 6 至 15 倍。这一发现可能部分解释了目前测量海水中溶解有机碳的方法之间存在的主要差异。
