Chlorophyll
High Chlorophyll measurement indicates high nutrient levels, specifically phosphorus and Nitrogen, and threatens water ecosystems. Waters with high nutrient levels from fertilisers, sewage treatment and other runoff have higher Chlorophyll-a concentrations, indicating low water quality.
Why is Chlorophyll Important to Measure in Water?
Chlorophyll is the green pigment found in plants and is essential for photosynthesis. Measuring Chlorophyll in water is important to estimate the abundance of phytoplankton. Monitoring Chlorophyll levels directly tracks algal growth, and if growth is excessive, it indicates high nutrients levels and risk of lower water quality.
What are Chlorophyll Indicators of Low Water Quality?
It’s natural for Chlorophyll levels to fluctuate, as concentrations can be higher after rainfall if the rain flushes nutrients into the water. However, very elevated concentrations of Chlorophyll can indicate an increase in nutrients, while increasing trends can show the eutrophication of ecosystems.
Chlorophyll A
Chlorophyll-a is a measurement of the amount of algae in a water body, which can also be used to classify a tropic condition of a waterbody. While algae is a natural component of freshwater ecosystems, too much of it can cause aesthetic problems like bad odour and green appearance and decrease Dissolved Oxygen levels.
Some algae can produce toxins that are a hazard for the public when found in high concentrations. For example, a symptom of degraded water quality is the increase of algae biomass measured by the concentration of Chlorophyll-a. High levels of Chlorophyll concentrate can indicate poor water quality, while low levels suggest the water condition is good.
Chlorophyll B
Chlorophyll-b is the accessory pigment, which passes trapped energy into Chlorophyll-a.
How Do You Measure Chlorophyll in Water?
One way of measuring the Chlorophyll-a in algae is through filters, where water passes through, and algae get caught on the filters. Another way of measuring Chlorophyll-a is the information provided by satellite pictures, like how the intensity of colours in photos relates to chlorophyll-a’s concentration in the water. The Waka includes room to upgrade and add on our Chlorophyll sensor.
What are the Testing Methods for Chlorophyll Water Levels?
There are various testing techniques to measure Chlorophyll, like spectrophotometry, high-performance liquid chromatography, and fluorometry.
Chlorophyll levels essentially indicate nutrients, using algae and phytoplankton measurements. For example, increased Chlorophyll levels will be an indicator of excessive nutrients in hand with changing water Temperature and pH levels.
Nutrients
Increased Chlorophyll levels are an indicator of increased nutrients. While the amount of algae and phytoplankton can cause Chlorophyll levels to increase, the fuelling factor is often excessive nutrients. For algae and phytoplankton to grow and survive, nutrients like phosphorus and Nitrogen are essential. But the more the nutrients, the more growth and the more Chlorophyll, indicating degrading water quality.
Water Temperature
An increase in Water Temperature can lead to an increase in Turbidity and, therefore, Chlorophyll. As temperature increases, so can plankton. An increase in algae and phytoplankton is measured by Chlorophyll concentration, relating directly to temperature. Photosynthesis is initiated by heat, and as photosynthesis production increases, so will phytoplankton and algae reproduction rates, causing increased Chlorophyll levels.
pH Levels
pH Levels can be a result of Chlorophyll changes and vice versa. The amount of Chlorophyll in water can affect pH, as a high concentration of phytoplankton and algae can increase the pH due to the decrease of carbon dioxide in the water. pH and Chlorophyll changes can indicate poor water quality, as Dissolved Oxygen levels also decrease, threatening aquatic life survival.
Nutrients
Increased Chlorophyll levels are an indicator of increased nutrients. While the amount of algae and phytoplankton can cause Chlorophyll levels to increase, the fuelling factor is often excessive nutrients. For algae and phytoplankton to grow and survive, nutrients like phosphorus and Nitrogen are essential. But the more the nutrients, the more growth and the more Chlorophyll, indicating degrading water quality.
Using Chlorophyll Levels to Indicate Water Quality
Chlorophyll levels rise as nutrients increase, Water Temperature changes, pH levels become more acidic, and Dissolved Oxygen levels decrease. All parameters are used to determine water quality. Increased nutrients can indicate unsafe drinking water, while reduced oxygen levels can show aquatic life is at risk, which both cause Chlorophyll levels to rise and can be an overall indicator of water quality.
Chlorophyll and Water Quality Monitoring Updates
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