Jackson Lake Analysis

Transcription

1 Jackson Lake Analysis

2 Lake Zones

3 Lake Zones Limnetic Zone- open water far from shore Light penetrates shallow, allowing photosynthesis Supports phytoplankton (algae, protists, cyanobacteria) which then supports zooplankton sunlight intensity decreases w/ depth & water temperature ProfundalZone-volume of water sunlight does not reach No photosynthetic life Low dissolved oxygen Benthic Zone- Extends f/ shore to deepest point bottom sediment, surface layer abundant w/ organisms Invertebrates live in mud (eating detritus or each other)

4 Lakes Zones Littoral Zone- nutrient rich edges of water, shallow - aquatic plants grow -invertebrates (insect larvae, snails, crayfish live here (birds, turtles, fish, amphibians eat them)

5 Lakes Dissolved oxygen Oxygen is produced during photosynthesis and consumed during respiration and decomposition May change with lake depth Light can only penetrate a specific distance, so photosynthesis can only happen in that area At the bottom of the lake, no photosynthesis, only oxygen consumption» Oxygen consumption is going to be greatest at the bottom of the lake

6 Lakes Dissolved Oxygen (cont) Wind can also stir the oxygen content in the lake to create an even consistency throughout. May change with the seasons Warmer temperatures speed up rates of photosynthesis and decomposition Presence of ice cover also has an influence Growing seasons influence amount of oxygen» Spring lots of photosynthesis» Fall lots of decomposition

7 Electrical conductivity estimates the amount of total dissolved salts (TDS), or the total amount of dissolved ions in the water Controlled by Rock types (geology)-what materials are present in the rock and if those materials cause ions because of their chemistry Size of the watershed relative to the area of the lake

8 Electrical Conductivity (cont) Other sources of ions to lakes» Wastewater» Urban runoff» Agricultural run off» Atmospheric inputs Evaporation rates» Water is the only thing that evaporates, dissolved solids stay behind Bacterial metabolism in the hypolimnion

9 ph measure of the concentration of hydrogen ions The ph of water determines the solubility and biological availability of chemical components such as nutrients (phosphorus, nitrogen, and carbon) and heavy metals (lead, copper, cadmium, etc.). Solubility amount that can be dissolved in water Biological availability amount that can be utilized by aquatic life

10 Temperature Can affect function of organisms (cold-blooded can t regulate their internal body temperature) Can affect rates of chemical reactions (warmer temperatures increase rates of reaction

11 Turbidity How clear the water is The greater the amount of total suspended solids (TSS) in the water, the murkier it appears and the higher the measured turbidity Causes phytoplankton, shoreline erosion, resuspended bottom sediments Can modify light penetration affect photosynthetic rates Can increase costs of purification

12 Stream Flow Called discharge, represented by Q determined with rating curves developed for each stream and subsequently used to calibrate flow Average flow measure velocity of the stream at various depths and various positions along the stream affects temperature of the water, concentration of various substances in the water, and the distribution of habitats and organisms throughout the stream directly affects amount of oxygen in the water Higher volumes of faster moving water, especially if it creates "white water," increases the diffusion of atmospheric oxygen into the water