Limnology of an equatorial high mountain lake - Lago San Pablo, Ecuador: The significance of deep diurnal mixing for lake productivity
Limnology of an equatorial high mountain lake - Lago San Pablo, Ecuador: The significance of deep diurnal mixing for lake productivity
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DOI：
10.1016/s0075-9511(02)80015-9
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发表时间：
2002-05-01
期刊：
影响因子：
1.7
通讯作者：
Casallas, J
中科院分区：
文献类型：
--
作者：
Gunkel, G;Casallas, J
赤道高山湖泊是一种特殊类型的湖泊，主要出现在南美洲的安第斯山脉以及中非和亚洲。它们出现在海拔几千米的高度，是冷水湖（0.01毫克/升，可溶性无机氮> 0.2毫克/升）。氮和磷在表层全年都是有效的（N-sol，inorg（.）= 0.3至1.7 mg/l N，SRP = 0.04至0.63 mg/l P）。N/P比值有时> 14，有时< 10，表明营养限制因子的变异性。考虑到营养水平，浮游植物生物量相当低（平均每毫升约4 000个细胞;最大细胞数：1998年为13 000个，1999年为10 000个）。1998年和1999年表层叶绿素含量（Chl a）的平均值分别为10 mug/l和11 mug/l，最大值分别为16 mug/l和22 mug/l。浮游植物的生产可能受到营养盐（主要是氮）的限制，但对流也会导致生物量的显著损失。湖泊的透光带小于其表水层，表明光辐射在较深的水体中是有限的，这是由于夜间冷却破坏层化而导致的弱温跃层造成的。
Equatorial high mountain takes are a special type of lake occurring mainly in the South American Andes as well as in Central Africa and Asia. They occur at altitudes of a few thousand meters above sea level and are cold-water lakes ( 0.01 mg/l, and soluble inorganic nitrogen > 0.2 mg/l. Nitrogen and phosphorus are available in the epilimnion all year round (N-sol, inorg(.) = 0.3 to 1.7 mg/l N, SRP = 0.04 to 0.63 mg/l P). The N/P ratio is sometimes > 14, sometimes < 10, indicating a variability of the limiting nutrient factor. Considering the nutrient level, the phytoplankton biomass is quite low (about 4,000 cells per ml on average; maximum cell number: 13,000 in 1998 and 10,000 in 1999). The mean epilimnic chlorophyll content (Chl a) was 10 mug/l in 1998 and 11 mug/l in 1999, and the maximum Chl a content was 16 and 22 mug/l in 1998 and 1999, respectively.Phytoplankton production can be limited by nutrients, mainly nitrogen, but convective currents can also cause a significant loss of biomass. The lake's euphotic zone is smaller than its epilimnic zoned indicating that light radiation is limiting in the deeper water body, this is caused by a weak thermocline due to destratification by nocturnal cooling, the atelomixis.