The onset of meromixis during restoration of Mono Lake, California: Unintended consequences of reducing water diversions
The onset of meromixis during restoration of Mono Lake, California: Unintended consequences of reducing water diversions
复制标题
加利福尼亚州莫诺湖恢复期间梅洛米西斯的爆发：减少引水的意外后果
DOI：
10.4319/lo.1998.43.4.0706
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发表时间：
1998
影响因子：
4.5
通讯作者：
J. Melack
中科院分区：
文献类型：
--
作者：
R. Jellison;J. Romero;J. Melack
自1941年以来，莫诺湖流域的淡水改道导致其规模逐渐缩小，湖水盐度增加了近一倍，并产生了相关的环境影响。为了恢复莫诺湖，加利福尼亚州修改了洛杉矶的水权，限制改道，直到水面高度比1982年的低点高出6米。由于湖的体积减少，1995年改道的停止和高于平均水平的融雪径流导致地表海拔突然上升1米，并开始持续的化学分层（meromixis）。利用一维垂直混合模式进行的长期模拟表明，考虑到国家的管理政策，目前的meromixis可能会持续几十年。1980年代中期，在1982-1983年创纪录的融雪径流和减少的改道导致垂直混合、养分循环和初级生产力的减少之后，出现了类似的meromixis。这段时期在长期干旱和恢复改道后结束。预测的几十年meromixis期的生态后果在很大程度上是未知的。
Diversions of freshwater streams out of the Mono Lake basin since 1941 have led to a gradual decrease in size, an approximate doubling of lake‐water salinity, and associated environmental impacts. To restore Mono Lake, the state of California amended Los Angeles' water rights by restricting diversions until the surface elevation rises 6 m above its 1982 low stand. Given the reduced volume of the lake, the cessation of diversions and an above average snowmelt runoff in 1995 led to an abrupt l‐m rise in surface elevation and the onset of persistent chemical stratification (meromixis). Long‐term simulations using a one‐dimensional vertical mixing model modified for application to hypersaline Mono Lake predict the current episode of meromixis is likely to persist for several decades, given the management policy of the state. A similar episode of meromixis in the mid‐1980s following record snowmelt runoff in 1982–1983 and reduced diversions led to reductions in vertical mixing, recycling of nutrients, and primary productivity. That episode ended following an extended period of drought and the resumption of diversions. The ecological consequences of the predicted multidecade period of meromixis are largely unknown.