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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} \subsection{North Lowland Lake (NL)}  North1 lake is a North  lowland is an  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.  All limiting nutrients are above of 90 percent available for phytoplankton in all 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 \subsection{North Higland  Lake} North 2 lakes highland lake  corresponds with ahighland  mesotrophic ecosystem in a cool North-Temperate climate (Mean 5.3ºC). Levels of chlorophyll are between 2.2.-6.2 mg/m3. The surface is covered with ice in winter (end of November, December, January and early February). Ice covering forms a barrier to the wind which minimizes losses of water evaporation while the bottom of the lake remains unfrozen. The water column does not thermostratified and is permanently well mixed whit levels of 50 percent in summer and 90 percent in winter. The maximum flows are in spring and autumn (9.6) with minimum flow in summer(0.6). Evaporation is reduced because their water is more or less cold and vapour-pressure gradients are no large (mean of 9,262). Retention Time is maximum in summer with 100 days. Oxygen concentration is upper to 10 mg/lt in the three layers. pH mean values are around 7 to 7.3, but it moves in a range of 6.7 to 7.8 from the surface to bottom. Variables correlations are more seasonal than the N1. It means the period of summer is related with high retention time, higher pH and winter season with the higher levels of oxygen, inflow and outflow and oxygen. However, there is a more strong correlation of benthic and sediment Oxygen. 
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\subsection{Tropical Lake}  The Tropical Lake is a  Hyper-eutrophic ecosystem (Chlorophyll > 19.2 mg/lt) located in a moist Tropical climate (North climate, at north  of the equator, near to the tropic of cancer). cancer with a mean temperature of 25ºC in surface layer.  This has one wet season and one dry season. Higher irradiance conducts to higher temperatures (Mean) and smaller thermal differences between layers. For that reason,  the water column is permanently warm and stratified. As stratification Stratification  is due to the heat exchange, but is less stable than at higher latitudes, the wind could have great incidence in the mixing of the water column. Thus, intraseasonal variations have an effect in thickness of the mixed layer than other morphometrically similar temperate lakes  (AES, Lewis). The maximum flow of water is in the wet season, and minimum flow is in the dry season. Episodes of heat and mixing, affects the nutrient cycling and plankton dynamics. It is highlighted that primary production in tropical lakes is about twice than higher latitudes. Also, it is known that Nitrogen is the more limiting nutrient. In this case, there are more equilibrium among species inside phyto and periphyton communities (around 33 percent for diatoms, green algae and cyanobacteria). Zooplankton populations are dominated by herbivorous (90), benthos by detritivores invertebrates (84.4) and fishes (87).