How can Nitrogen Affect Water Quality and Human Health?
Nitrogen is an essential nutrient for plant growth, and is one of the primary components of manure and commercial fertilizers. However, although nitrogen is very productive when applied to crops, excess nitrogen can have negative impacts in our lakes, rivers, and groundwater.
· Because of its fertilizing properties, nitrogen is a key contributing factor to algae growth in streams and lakes.
· Excess nitrogen in rivers and streams can be toxic to aquatic animals at high levels. This toxicity is due to ammonium hydroxide (NH4OH), which is produced at greater rates under conditions that are common where waste spills have occurred (such as low oxygen levels, high pH, and high temperature). Toxic levels of ammonium hydroxide are usually due to pollution from manure and sewage spills, and can result in fish kills and loss of other aquatic organisms.
· Nitrogen pollution also leads to human health concerns about groundwater contamination. Unlike phosphorus, which binds to the soil's surface, nitrogen filters down through the soil easily and can enter drinking wells. Infants less than six months are most susceptible to nitrate poisoning. High nitrate levels in groundwater can reduce the blood's capacity to carry oxygen, causing a fatal condition in infants called "blue baby syndrome." For this same reason, deaths can also occur in livestock that drink from a water supply high in nitrates. Pregnant or nursing women are advised to avoid water with high nitrate levels. Adults with heart or lung disease, certain inherited enzyme defects, or cancer may have increased sensitivity to the toxic effects, and adults with lifetime exposures to high nitrate levels may experience related health issues. The federal safety standard for nitrate is 10 mg/L, and 6.5% of Wisconsin's private wells exceed this safety standard.
How can Nitrogen and Phospherous Levels be Reduced?
For farmers, nutrient management is an integral part of business, and there are important steps that can be taken to reduce their nutrient loss to streams and lakes. The two main ways of reducing the nutrients that enter our waterways from agriculture are 1) decreasing the amount of nutrients applied to the landscape, and 2) preventing spills, runoff, and erosion from transporting those nutrients to our waterways. Decreasing excess nutrients applied to the landscape is the first step necessary for maintaining good water quality.
· Careful nutrient management planning can help farmers determine how much nitrogen and phosphorus is in their manure and how much the crops on each field require to be productive. This planning can help farmers apply only as much nitrogen and phosphorus as their crops will use, preventing excess runoff. In areas that already have phosphorus buildup in the soil or impacted waterways, farmers may need to manage specifically to reduce phosphorus levels.
· One way livestock operators can reduce unnecessary phosphorus in manure is by changing their feed supplements. Phosphorus is typically fed to cattle to ensure reproductive success. However, new research is showing that lower phosphorus levels in feed can be optimal for both maintaining herd health and for cost-effectiveness.
The second important step is to prevent the nutrients that are stored or applied to the land from getting into waterways.
· In many cases, manure should be stored over the winter while the ground is frozen. Because of this, manure storage facilities are a management option often chosen for operations that handle large quantities of manure. Sound construction and maintenance of these storage structures is essential to preventing leaks to groundwater and overflows that can damage nearby streams and lakes.
· Prevention of erosion and runoff is essential for keeping nutrients out of our lakes and streams. Maintaining good plant cover is one of the most effective ways to reduce the amount of soil and phosphorus that runs off into the water. Plant roots stabilize the soil and help reduce erosion. Buffer strips of grasses or trees along stream banks catch runoff and sediments flowing from upland fields and trap them before they enter waterways. Well-vegetated uplands and buffers are critical for water quality.
By following these practices and using good nutrient management planning, farmers can reduce nutrient-rich runoff from their farms and fields. This, combined with steps taken by all of Wisconsin's citizens and businesses, can help protect our beautiful water resources.
Source: http://www.dnr.state.wi.us/org/water/wm/nps/ag/waterquality.htm
21 September 2007
Coliform and Algae
These pictures were taken 19 July 2007 in the Maria slough on Seabird Island. Test results prove that this build up is algae high in coliform. Read on to learn about what this does to waterways.
Fecal coliform is generally used as a water quality measure of bacterial contamination. Coliform is a group of bacteria that, while generally harmless, does have strains such as E. coli (Escherichia coli) that can be harmful. E. coli can cause intestinal disorders, as well as other diseases such as cholera and typhoid fever. Another organism found in manure is Cryptosporidium, a single-celled parasite that causes diarrhea and stomach cramps when ingested. Cryptosporidium was responsible for an outbreak in Milwaukee's drinking water system in 1993.
Direct access of livestock to streams and ponds can also be a problem if the streambank is not well vegetated. Not only do cattle and hogs "direct deposit" manure into the water, they can also overgraze and trample streambanks, leading to erosion problems. Trampled banks also damage fish habitat, destroying overhangs used for shelter and compacting stream bottoms that are used for spawning and feeding.
An important characteristic of phosphorus that has significant implications for water quality is its tendency to bind to soil particles. Because of this, when phosphorus is applied to fields it stays relatively immobilized and stable on land as long as the soil remains intact. However, when land suffers from erosion, soil is washed into waterways and the phosphorus attached to it is then released into the water. Once phosphorus enters the water, the algae bloom cycle begins. Because of this process, erosion and runoff are key issues that need to be addressed for good phosphorus management.
How can Bacteria and Pathogens from Manure make Water Unsafe?
Manure can contain bacteria and other organisms that can be harmful to humans if they get into our waterways or groundwater. Pathogens can become a problem when manure runs off into lakes where people swim or have other direct bodily contact with the water. If a person or animal swallows water from a contaminated source, illness can result. Contamination can also be a concern in drinking water. Generally, municipal drinking water treatment plants do a good job of sanitizing community water supplies, so municipal drinking water supplies are rarely contaminated from manure. However, private wells can become contaminated by pathogens from manure.
Fecal coliform is generally used as a water quality measure of bacterial contamination. Coliform is a group of bacteria that, while generally harmless, does have strains such as E. coli (Escherichia coli) that can be harmful. E. coli can cause intestinal disorders, as well as other diseases such as cholera and typhoid fever. Another organism found in manure is Cryptosporidium, a single-celled parasite that causes diarrhea and stomach cramps when ingested. Cryptosporidium was responsible for an outbreak in Milwaukee's drinking water system in 1993.
How does Manure in Water Lead to Algae Booms and Kills Fish?
Direct runoff of manure from fields or manure storage facilities that have been inadequately constructed or maintained are important management concerns. If a rain occurs after manure is spread on crop or hay fields, the phosphorus may run off into nearby waterways instead of sinking into the ground. This is especially problematic during the spring, when manure spread over the winter is washed away by the spring snowmelt. Since this manure is delivered directly into waterways, this can be a major contributor of phosphorus to the streams and lakes. Likewise, manure storage facilities need to be structurally sound and have enough capacity to handle the manure generated at the farm, to avoid leaks or overtopping.
As algae blooms grow, the mats that cover the water's surface block out sunlight from the larger plants below. These larger aquatic plants are essential for fish habitat, but can't survive without sunlight and start to die off. Before long, the short-lived algae also start to die, and large masses of dead algae and plant matter begin to decay. As a part of this decomposition process, bacteria are produced that use up oxygen from the water. This has major impacts. Since fish and aquatic insects need the oxygen that is dissolved in water to live, when that oxygen is used up by decaying algae massive fish kills can result, damaging fish populations. All of this decaying material has another unpleasant side effect, too-the odor of rotting algae and fish! All of these effects can turn your favorite stream or swimming hole into a stinking, green mess.
As algae blooms grow, the mats that cover the water's surface block out sunlight from the larger plants below. These larger aquatic plants are essential for fish habitat, but can't survive without sunlight and start to die off. Before long, the short-lived algae also start to die, and large masses of dead algae and plant matter begin to decay. As a part of this decomposition process, bacteria are produced that use up oxygen from the water. This has major impacts. Since fish and aquatic insects need the oxygen that is dissolved in water to live, when that oxygen is used up by decaying algae massive fish kills can result, damaging fish populations. All of this decaying material has another unpleasant side effect, too-the odor of rotting algae and fish! All of these effects can turn your favorite stream or swimming hole into a stinking, green mess.
How does Phospherous from Manure Affect Water Quality?
Direct runoff of manure from fields or manure storage facilities that have been inadequately constructed or maintained are important management concerns. If a rain occurs after manure is spread on crop or hay fields, the phosphorus may run off into nearby waterways instead of sinking into the ground. This is especially problematic during the spring, when manure spread over the winter is washed away by the spring snowmelt. Since this manure is delivered directly into waterways, this can be a major contributor of phosphorus to the streams and lakes. Likewise, manure storage facilities need to be structurally sound and have enough capacity to handle the manure generated at the farm, to avoid leaks or overtopping.
Direct access of livestock to streams and ponds can also be a problem if the streambank is not well vegetated. Not only do cattle and hogs "direct deposit" manure into the water, they can also overgraze and trample streambanks, leading to erosion problems. Trampled banks also damage fish habitat, destroying overhangs used for shelter and compacting stream bottoms that are used for spawning and feeding.
An important characteristic of phosphorus that has significant implications for water quality is its tendency to bind to soil particles. Because of this, when phosphorus is applied to fields it stays relatively immobilized and stable on land as long as the soil remains intact. However, when land suffers from erosion, soil is washed into waterways and the phosphorus attached to it is then released into the water. Once phosphorus enters the water, the algae bloom cycle begins. Because of this process, erosion and runoff are key issues that need to be addressed for good phosphorus management.
14 September 2007
Western Toads
These are pictures I took of Western toads in Laidlaw, BC. They were taken approximately June 2006.
Scientific name: Bufo boreas.
These frogs can be picked out from a crowd because of their light colored stripe right down their backs. Their 'warts' may be reddish and are surrounded by black marks. Remember, 'wart's are actually glands that hold poison which they release when something tries to eat them.
The call of the Western toad almost sounds like the peeping of little chicks. This species is classed as Special Concern.
Egg masses are laid in bead-like strings, holding approximately 17,000 eggs! They breed from April to June.
For more information on Western toads, visit:
Red-legged Frogs
I took these pictures 13 September 2007 at the Greater Vancouver Zoo husbandry. These are both Red-legged froglets. They will be released back into the wild after proven healthy and marking. The scientific name for Red-legged frog is Rana aurora. Rana being the family of 'True frogs', and cousin to the Oregon Spotted frog. The Red-legged frog looks almost identical to the Oregon Spotted frog and is mistaken for one another often. However, there are some noticable differences between the two.
Red-legged frogs webbing do not extend to the end of the toe like the Oregon Spotted frog. The eyes on the Red-legged frogs look out to the side while the Oregon Spotted frogs look almost directly up. The call is different with both species.
Some of the differences are:
They both have a light stripe on the jaw. They both lay between 500-700 eggs per egg mass at about the same time (Feb-March). Egg masses are very difficult to tell apart unless laid in the traditional manner. Red-legged frogs lay their eggs attached to submerged vegetation, however, after awhile, these masses will rise to the surface of the water. Oregon Spotted frogs will lay their egg masses in tight, communal groups on the surface of the water. Red-legged frogs can be found outside of the water, while Oregon Spotted frogs are rarely seen period.
For more information on Red-legged frogs, visit:
For more information on Red-legged frogs, visit:
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