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In general, Arctic lake systems are classified as oligotrophic due to their low primary production, represented in chlorophyll values of 0.8-2.1 mg/m3. The lake’s water column, or limnetic zone, is well-mixed; this means that there are no stratifications (layers with different temperatures). During winter (October to March), the surface of the lake is ice covered. During summer (April to September), ice melts and the water flow and evaporation increase, as shown in Figure **. Consequently, the two climatic periods (winter and summer) in the Arctic region cause a typical hydrologic behavior in lakes as the one shown in Figure **.  This hydrologic behavior influences the physiochemical subsystem of the lake.  Limiting Nutrients in the form of nitrates, silicates and carbon dioxide are between 90 and 100 percent available for phytoplankton in all year. Thus, phytoplankton and periphyton biomass is dominated by planktonic (38.6 percent) and Periphytic diatoms (45). For zooplankton, the 91.7 percent is dominated by herbivorous. At the Benthos invertebrates detritivores with a 86.8 percentage of total abundance and piscivorous fishes with the 85.8 percent are the two groups with high dominance in their respectively group.  \subsection{North1 Lake}  North1 lake is a lowland eutrophic lake, located in a warm North-Temperate climate (mean Tº of 14ºC). Their primary production expressed in mg/m3 of chlorophyll is around 6.3-19.2. There are four seasons in a year, winter, spring, summer and autumn. In summer, the flow variations (Inflow and outflow fall to 3.5 from 25.2 and retention time increases to 100 days), the lack are lack or absence of seasonal wind and high temperatures (24ºC), causes the water column thermostratification. Stratification is expressed in generation of two layers. At the border of these layers, temperature changes dramatically (24ºC Surface to 20.6 in Planktonic layer, to 17.3 in Benthic layer). Water above and below of thermocline do not mix. The warmer water is near the surface and denser water is near the bottom. In winter, there is no ice covering in the surface. Opposite to the summer when the flow is minimum, in spring and autumn the water column overturns (Retention Time of 14 days and Zone Mixing of 100%), causing increases in conductivity.  In summer, depletions of oxygen at the three layers are more drastic than Artic lakes (below 8.7 mg/lt). Oxygen is directly correlated with the zone mixing, inflow and outflow, and inverse correlated with the others parameters (fig. **), especially with pH and retention time.  Limiting Nutrients in the form of nitrates, silicates and carbon dioxide All limiting nutrients  are above of 90 percent available for phytoplankton in all layers. seasons.  According with this availability, phytoplankton and periphyton biomass composition is dominated by planktonic (47) and benthic (34.3) diatoms. This way, 100 percent of zooplankton composition is reached by herbivorous zooplankton and fish community is dominated by benthic fish (67.6). \subsection{North2 Lake}