Rapid biologically mediated oxygen isotope exchange between water and phosphate
Rapid biologically mediated oxygen isotope exchange between water and phosphate
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DOI：
10.1029/2001gb001430
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发表时间：
2002-03-01
影响因子：
5.2
通讯作者：
Luz, B
中科院分区：
文献类型：
--
作者：
Paytan, A;Kolodny, Y;Luz, B
[1]为了更好地限制水和磷酸盐之间通过生化反应进行氧同位素交换的速率，1988年在以色列Elat的Aquarium Plant进行了一系列受控实验。不同种类的藻类和其他生物体在受控条件下在海水槽中生长，并监测水温和氧同位素组成（δ（18）O（w））。在实验的不同阶段，测量了生物的食物源、组织中磷酸盐的氧同位素组成（δ（18）O（p））和溶解无机磷酸盐（DIP）的δ（18）O（p）。结果表明，磷化合物和水之间的细胞内氧同位素交换是非常迅速的，发生在食物链的各个层面。通过这些反应，软组织的δ（18）O（p）值比δ（18）O（w）高23- 26 ppm，DIP的δ（18）O（p）值比δ（18）O（w）高约20 ppm。在这些实验中，未观察到δ（18）O（p）值与温度或P浓度之间的相关性。我们的数据表明，生物再循环和细胞内磷周转，其中涉及动力学分馏效应，是控制的主要参数的三角洲（18）O（p）值溶解在水生系统中的P化合物。这一信息是基本的任何应用程序的溶解有机或无机磷酸盐的三角洲（18）O（p），以量化在水生系统中的磷循环的动力学。
[1] In order to better constrain the rate of oxygen isotope exchange between water and phosphate via biochemical reactions a set of controlled experiments were conducted in 1988 at the Aquaculture Plant in Elat, Israel. Different species of algae and other organisms were grown in seawater tanks under controlled conditions, and the water temperature and oxygen isotopic composition (delta(18)O(w)) were monitored. The oxygen isotopic composition of phosphate (delta(18)O(p))in the organisms' food source, tissues, and the delta(18)O(p) of dissolved inorganic phosphate (DIP) were measured at different stages of the experiments. Results indicate that intracellular oxygen isotope exchange between phosphorus compounds and water is very rapid and occurs at all levels of the food chain. Through these reactions the soft tissue delta(18)O(p) values become 23-26parts per thousand higher than delta(18)O(w), and delta(18)O(p) values of DIP become similar to20parts per thousand higher than delta(18)O(w). No correlation between delta(18)O(p) values and either temperature or P concentrations in these experiments was observed. Our data imply that biogenic recycling and intracellular phosphorus turnover, which involves kinetic fractionation effects, are the major parameters controlling the delta(18)O(p) values of P compounds dissolved in aquatic systems. This information is fundamental to any application of delta(18)O(p) of dissolved organic or inorganic phosphate to quantify the dynamics of phosphorus cycling in aquatic systems.