Lentic vs Lotic Systems
Lentic and lotic refer to continental freshwater systems or aquatic ecology versus marine or estuarine waters. Lentic means still water systems whereas lotic refers to flowing water systems. Lentic systems can range from small, temporary rainwater pools a few inches deep to ponds of various sizes and depth to the largest and deepest lakes any where on earth. Lotic systems can range from a spring that is only a few centimeters wide to a major river that is miles in width and thousands of miles long. Many of the biota and food webs are quite similar from lentic to lotic systems while others are very different. Lotic systems can have sections that are similar to lentic systems, especially where the flowing water is deep and moves slowly. In general, there is much more variability within lotic systems because biota, especially micro scale organisms, must be specialized to live with flowing water conditions. While light, temperature, chemistry and substrate materials play important roles in determining the type of bacteria, primary producers, invertebrates and vertebrates that thrive in lentic and lotic systems, flow is a key determinant of both abiotic and biotic influences on the ecology of lotic systems.
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A Lentic Ecosystem
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A Lotic Ecosystem
Eutrophic vs Oligotrophic
A combination of different factors can lead to a being either oligotrophic or eutrophic, including human land management and use, the water's natural temperature and the size, including shape, depth and volume.
Oligotrophic and eutrophic bodies of water can be described in terms of productivity, in which an oligotrophic body, thanks to its low nutrient level and generally inhospitable environment for life, is said to be less productive while the more life-sustaining eutrophic body type is said to be more productive.
Oligotrophic means full of lots of oxygen and less nutrients, since the nutrients are consumed by Diatom Algae and diatoms by zooplankton and fish.
Eutrophic means having lots of mineral and organic nutrients. This means it has a lot of plants and algae and less amount of Diatoms. Other algae are not consumed by fish, so they die and decompose, so there is very little oxygen in the water and other organic life (fish and insects) dies.
Oligotrophic and eutrophic bodies of water can be described in terms of productivity, in which an oligotrophic body, thanks to its low nutrient level and generally inhospitable environment for life, is said to be less productive while the more life-sustaining eutrophic body type is said to be more productive.
Oligotrophic means full of lots of oxygen and less nutrients, since the nutrients are consumed by Diatom Algae and diatoms by zooplankton and fish.
Eutrophic means having lots of mineral and organic nutrients. This means it has a lot of plants and algae and less amount of Diatoms. Other algae are not consumed by fish, so they die and decompose, so there is very little oxygen in the water and other organic life (fish and insects) dies.
Lymnology
Lymnology is the study of inland waters, or lakes. It is often regarded as a division of ecology or environmental science. It consists of four different layers.
- The hypolimnion is the dense, bottom layer of water in a thermally-stratified lake. It is the layer that lies below the thermocline. Typically the hypolimnion is the coldest layer of a lake in summer, and the warmest layer during winter.In deep, temperate lakes, the bottom-most waters of the hypolimnion are typically close to 4 °C throughout the year. The hypolimnion may be much warmer in lakes at warmer latitudes.
- The epilimnion is the top-most layer in a thermally stratified lake, occurring above the deeper hypolimnion. It is warmer and typically has a higher pH and higher dissolved oxygen concentration than the hypolimnion. Being exposed at the surface, it typically becomes turbulently mixed as a result of surface wind-mixing. It is also free to exchange dissolved gases such as O2 and CO2 with the atmosphere. Because this layer receives the most sunlight it contains the most phytoplankton. As they grow and reproduce they absorb nutrients from the water, when they die they sink into the hypolimnion resulting in the epilimnion becoming depleted of nutrients.
- A thermocline is a thin but distinct layer in a large body of fluid (e.g. water, such as an ocean or lake, or air, such as an atmosphere) in which temperature changes more rapidly with depth than it does in the layers above or below. In the ocean, the thermocline may be thought of as an invisible blanket which separates the upper mixed layer from the calm deep water below. Depending largely on season, latitude and turbulent mixing by wind, thermoclines may be a semi-permanent feature of the body of water in which they occur or they may form temporarily in response to phenomena such as the radiative heating/cooling of surface water during the day/night. Factors that affect the depth and thickness of a thermocline include seasonal weather variations, latitude and local environmental conditions, such as tides and currents.
- The benthic zone is the ecological region at the lowest level of a body of water such as an ocean or a lake, including the sediment surface and some sub-surface layers. Organisms living in this zone are called benthos, e.g. the benthic invertebrate community, including crustaceans and polychaetes.[1] The organisms generally live in close relationship with the substrate bottom and many are permanently attached to the bottom. The superficial layer of the soil lining the given body of water, the benthic boundary layer, is an integral part of the benthic zone, as it greatly influences the biological activity which takes place there. Examples of contact soil layers include sand bottoms, rocky outcrops, coral, and bay mud.
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The 4 layers of a lake.
Trophogenic vs Tropholytic
Trophogenic can be described as the upper part of a lake where inorganic matter and nutrients are converted with photosynthesis into usable food for the animals which live there. Inorganic matter is converted to organic matter. The Trophogenic zone is different from it's counterpart, the Tropholytic zone. The Tropholytic zone is the area of the lake where sunlight is not sufficient enough to reach it. Due to the sunlight not being able to reach this zone, there is no photosynthesis and no easy access to food. Because there is an insufficient amount of food, decomposition primarily dominates this region.
Lake turnover is the process of a lake's water turning over from top (epilimnion) to bottom (hypolimnion). During the summer, the epilimnion, or surface layer, is the warmest. It is heated by the sun. The deepest layer, the hypolimnion, is the coldest. The sun's radiation does not reach this cold, dark layer.
During the fall, the warm surface water begins to cool. As water cools, it becomes moredense, causing it to sink. This dense water forces the water of the hypolimnion to rise, "turning over" the layers.
During the fall, the warm surface water begins to cool. As water cools, it becomes moredense, causing it to sink. This dense water forces the water of the hypolimnion to rise, "turning over" the layers.
Water Quality
ph-The pH measurement in water is the measurement of how acidic or basic a sample of water is. You measure the pH of water on a pH scale which ranges from 0 to 14 and the lower measurements being more basic.
O2- the O2 in water stands for how much oxygen is in a sample of water. Usually, rivers and streams will have more O2 in them as they are moving.
NO3- NO3 is the amount of nitrogen oxide in a sample of water. Heavy amounts of nitrogen oxide can be detrimental to aquatic life.
Chlorine- The measure of chlorine in water is the amount of chloride chemical gas in water. Chlorine is used usually to clean pools and ingestion of high amounts of chlorine by an organism can lead to death.
O2- the O2 in water stands for how much oxygen is in a sample of water. Usually, rivers and streams will have more O2 in them as they are moving.
NO3- NO3 is the amount of nitrogen oxide in a sample of water. Heavy amounts of nitrogen oxide can be detrimental to aquatic life.
Chlorine- The measure of chlorine in water is the amount of chloride chemical gas in water. Chlorine is used usually to clean pools and ingestion of high amounts of chlorine by an organism can lead to death.