Download Aquatic Plants and Algae

Algae & Aquatic Plants DIFFERENCES Algae •
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Not considered plants Unicellular, colonial or multicellular Lack roots, stem or leaves Aquatic Plants •
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Only multicellular Include roots, stems and leaves SIMILARITIES •
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Photosynthetic Include species which float and some which attach to substrate Source of organic matter which may be included as a base for the water body’s ecosystem food chain Provide oxygen to the water body Rely on temperature, water level, season, nutrients available and amount of sunlight penetrating the water column May have excessive growth in response to human activity, such as putting too many nutrients in the water body Aquatic Plants Floating • Most or all leaves float freely on the water surface • Roots may extract nutrients from water body bottom or from the water itself • Prefer stagnant, or very low flowing, water Water lilies Duckweed Submerged • Majority of the plant body is beneath the water’s surface • Usually have flexible and buoyant stems and leaves • Can root in many different water bottoms and tend to prefer shallower waters (3 feet deep or less) Elodea Emergent • Look like a terrestrial plant because most of the plant is above the water’s surface and usually along shorelines • Stem and leaves are often dry and only roots are submerged • Provide important habitats for fish, animals and insects as well as stabilize the shoreline Cattail Naiad Benefits of having a healthy aquatic plant community: •
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Improve water clarity by providing an increased surface for dirt particles to settle on and holds the sediment on the water floor, preventing it from being stirred Prevent algae blooms by taking up nutrients and resources that algae would otherwise use They have important ecological roles such as providing shelter, breeding sites or nesting sites for many insects and animals and they are an important food source for many herbivores and omnivores Prevent shoreline erosion by holding onto sediment that would otherwise wash away Disadvantages of aquatic plant overgrowth or lack of growth: •
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Disruption of ecological roles may occur by providing too much shelter to prey, starving predators or by providing too little shelter, causing over predation of the prey species. Breeding and nesting sites may also become covered in vegetation and no longer be used Excess vegetation may choke water pumps and foul recreational beaches and boat launches Lack of vegetation may discourage species introduction in newer water bodies or cause starvation in species already present, decreasing the ecosystem health Decrease available nutrients for other species with overgrowth by up taking all available nutrients and decreasing oxygen levels by increasing decaying matter. With lack of vegetation, the important organic nutrients required in an ecosystem structure may be absent How to prevent Aquatic Plant problems: •
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Reduce personal addition of nutrients, particularly phosphorus and nitrogen, into the water body. This can be achieved by reducing fertilizer run off and planting terrestrial plants along shorelines Pay attention to the water body’s plant community. If there are any significant changes that are occurring, the faster they’re recognized, the less energy and resources for corrective measures will be required Algae Types of Algae Green Algae • Very common • Cause odor and beach fouling • Often have a cotton candy like appearance on the water’s surface during a bloom Blue-­‐Green Algae • Most prominent algae involved in late summer blooms • Can be an irritant and toxin to humans and may even cause death in animals • Often have the appearance of spilled paint or pea soup during a bloom Diatoms • Remain microscopic and unicellular throughout lifecycle • Have a hard outer coating made of silica that cannot decompose Flagellates • Have one or more whip-­‐like tails called flagella that is used for movement • Can be unicellular and microscopic or in a colony visible to the naked eye Algae Blooms An algae bloom is an excessive algae growth in the response to favorable growth conditions. These conditions include high air and water temperature, high levels of available nutrients, strong sunlight exposure and extended periods of calm water. During the spring, nutrients and sunlight are in abundance and herbivore populations are decreased from the winter -­‐ this allows for smaller algae to thrive and bloom. As summer continues, herbivore populations recover and clear the waters of the algae. Later in the summer however, with higher temperatures and increasing nutrients, larger algae with gelatin coatings, that many herbivores don’t like to eat, bloom. These blooms often have an unpleasant odor and decrease the aesthetics of the water body and continue into early fall. Microalgae You won’t be able to see sole individuals with your eyes but they are visible when they form a colony or thread like filaments. Microalgae may be: I.
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Phytoplankton, which float on water surfaces, or Periphyton, which attach to a substrate partially or completely submerged under water. Macro algae These algae are multicellular organisms that may look like an aquatic plant. Benefits of having a healthy algae community: •
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They have important ecological roles such as being an important food source for many herbivores and omnivores Prevent shoreline erosion by some species as they can lay in heavy mats along the shore Improve water clarity when forming colonies and provide greater surface area for particle settlement and creating obstacles to particles, reducing their spread They are important water health indicators as some species can only survive in a small range of conditions. Past algae populations may also be looked at in sediment cores, which would allow researchers to understand the water’s health and characteristics throughout time Disadvantages of algae overgrowth or lack of algae: •
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Disruption of ecological food chain by starving algae depend species if there is a lack of algae and by causing population overgrowth of algae feeding species if overabundant Algae blooms may occur which can choke human infrastructure such as water pumps, decrease water body’s oxygen levels, over load the water with nutrients and/or be toxic and cause sickness or death in animals Decrease aesthetic appeal of the water body and surrounding areas, as algae may have a foul smell as well as a unappealing look How to prevent algae problems: •
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Reduce personal addition of nutrients, particularly phosphorus and nitrogen, into the water body. This can be achieved by reducing fertilizer run off and planting terrestrial plants along shorelines Occasionally create small currents through stagnant areas when temperatures rise at the end of the summer, as warm, stagnant water is an optimal growing environment for toxic algae