Nutrients as Major Water Pollutants

Nutrients as Major Water Pollutants According to the Environmental Protection Agency, over half of the nation’s streams and rivers are polluted, and of those, 19% are impaired by the presence of excess nutrients. What Is Nutrient Pollution? The term nutrient refers to sources of nourishment supporting organism growth. In the context of water pollution, nutrients generally consist of phosphorus and nitrogen which algae and aquatic plants use to grow and proliferate. Nitrogen is present in abundance in the atmosphere, but not in a form that is available to most living things. When nitrogen is in the form of ammonia, nitrite, or nitrate, however, it can be used by many bacteria, algae, and plants (heres a nitrogen cycle refresher). Generally, it is the overabundance of nitrates that causes environmental problems. What Causes Nutrient Pollution? Some common agricultural practices lead to excess nutrients in water bodies. Phosphorus and nitrates are important components of the fertilizers used in agricultural fields – they are present in both synthetic fertilizers and natural ones like manures. If the crops do not pick up all of the fertilizer applied, or if rain has a chance to wash it away before they are absorbed by plants, the excess fertilizer is flushed into streams. Another major source of nutrients also comes from the way agricultural fields are only used seasonally. Most crops are present in the fields over a relatively short growing season, and the rest of the year the soil is left exposed to the elements. Meanwhile soil bacteria is feasting on decaying roots and plant debris, releasing nitrates. Not only do bare fields cause sediment pollution, but this practice allows the massive release and washing away of nitrates.Sewage can carries nutrients to streams and water. Septic systems, especially if older or im properly maintained, can leak into streams or lakes. Households connected to municipal sewer systems also contribute to nutrient pollution. Wastewater treatment plants sometimes function improperly, and are periodically overwhelmed during heavy rain events and release sewage into rivers. Stormwater. Rain falling in urban or suburban areas picks up nutrients from lawn fertilizer, pet waste, and various detergents (for example, the soap used to wash one’s car in the driveway). The stormwater is then canalized into municipal drainage systems and released into streams and rivers, loaded with phosphorus and nitrogen.Burning fossil fuels release nitrogen oxides and ammonia into the air, and when those are deposited in water, they can contribute significantly to the excess nutrient problem. Most problematic are coal-fired power plants and gas- or diesel-powered vehicles. What Environmental Effects Do Excess Nutrients Have? Excess nitrates and phosphorus encourage the growth of aquatic plants and algae. Nutrient-boosted algae growth leads to massive algae blooms, visible as a bright green, foul smelling sheen on the water’s surface. Some of the algae making up the blooms produce toxins that are dangerous to fish, wildlife, and humans. The blooms eventually die off, and their decomposition consumes a lot of dissolved oxygen, leaving waters with low oxygen concentrations. Invertebrates and fish are killed when oxygen levels dip too low. Some areas, called dead zones, are so low in oxygen that they become empty of most life. A notorious dead zone forms in the Gulf of Mexico every year due to agricultural runoff in the Mississippi River watershed. Human health can be affected directly, as nitrates in drinking water are toxic, especially to infants. People and pets can also become quite ill from exposure to toxic algae. Water treatment does not necessarily solve the problem, and can in fact create dangerous conditions when chlorine interacts with the algae and produces carcinogenic compounds. Â   Some Helpful Practices Cover crops and no-till farming protect agricultural fields and mobilize nutrients. The cover plants die out in winter, and the following growing season they give back those nutrients to the new crop.Maintaining well vegetated buffers around farm fields and next to streams allows plants to filter out nutrients before they enter the water.Keep septic systems in good working order, and conduct regular inspections.Consider your nutrient inputs from soaps and detergents, and reduce their use whenever possible.In your yard, slow the water runoff and allow it to be filtered by plants and soil. To accomplish this, establish rain gardens, keep drainage ditches well vegetated, and use rain barrels to harvest roof runoff.Consider using pervious pavement in your driveway. These surfaces are designed to let water percolate into the soil below, preventing runoff. For More Information Environmental Protection Agency. Nutrient Pollution.

Richard Ewell - Civil War - Lieutenant General - Army of Northern Virginia

Richard Ewell - Civil War - Lieutenant General - Army of Northern Virginia Richard Ewell - Early Life Career: The grandson of the first US Secretary of the Navy, Benjamin Stoddert, Richard Stoddert Ewell was born in Georgetown, DC on February 8, 1817. Raised in nearby Manassas, VA by his parents, Dr. Thomas and Elizabeth Ewell, he received his initial education locally before electing to embark on a military career. Applying to West Point, he was accepted and entered the academy in 1836. An above average student, Ewell graduated in 1840 ranked thirteenth in a class of forty-two. Commissioned as a second lieutenant, he received orders to join the 1st US Dragoons which were operating on the frontier. In this role, Ewell assisted in escorting wagon trains of traders and settlers on the Santa Fe and Oregon Trails while also learning his trade from luminaries such as Colonel Stephen W. Kearny. Richard Ewell - Mexican-American War: Promoted to first lieutenant in 1845, Ewell remained on the frontier until the outbreak of the Mexican-American War the following year. Assigned to Major General Winfield Scotts army in 1847, he took part in the campaign against Mexico City. Serving in Captain Philip Kearnys company of the 1st Dragoons, Ewell took part in operations against Veracruz and Cerro Gordo. In late August, Ewell received a brevet promotion to captain for his heroic service during the battles of Contreras and Churubusco. With the end of the war, he returned north and served at Baltimore, MD. Promoted to the permanent grade of captain in 1849, Ewell received orders for the New Mexico Territory the following year. There he conducted operations against the Native Americans as well as explored the newly-acquired Gadsen Purchase. Later given command of Fort Buchanan, Ewell applied for sick leave in late 1860 and returned east in January 1861. Richard Ewell - The Civil War Begins: Ewell was recuperating in Virginia when the Civil War began in April 1861. With the secession of Virginia, he resolved to leave the US Army and seek employment in the Southern service. Formally resigning on May 7, Ewell accepted an appointment as a colonel of cavalry in the Virginia Provisional Army. On May 31, he was slightly wounded during a skirmish with Union forces near Fairfax Court House. Recovering, Ewell accepted a commission as a brigadier general in the Confederate Army on June 17. Given a brigade in Brigadier General P.G.T. Beauregards Army of the Potomac, he was present a the First Battle of Bull Run on July 21, but saw little action as his men were tasked with guarding Union Mills Ford. Promoted to major general on January 24, 1862, Ewell received orders later that spring to take command of a division in Major General Thomas Stonewall Jacksons army in the Shenandoah Valley. Richard Ewell - Campaigning in the Valley Peninsula: Joining Jackson, Ewell played key roles in a string of surprising victories over superior Union forces led by Major Generals John C. Frà ©mont, Nathaniel P. Banks, and James Shields. In June, Jackson and Ewell departed the Valley with orders to join General Robert E. Lees army on the Peninsula for an attack on Major General George B. McClellans Army of the Potomac. During the resulting Seven Days Battles, he took part in the fighting at Gaines Mill and Malvern Hill. With McClellan contained on the Peninsula, Lee directed Jackson to move north to deal with Major General John Popes newly-formed Army of Virginia. Advancing, Jackson and Ewell defeated a force led by Banks at Cedar Mountain on August 9. Later in the month, they engaged Pope in the Second Battle of Manassas. As the fighting raged on August 29, Ewell had his left leg shattered by a bullet near Brawners Farm. Taken from the field, the leg was amputated below the knee. Richard Ewell - Failure at Gettysburg: Nursed by his first cousin, Lizinka Campbell Brown, Ewell took ten months to recover from the wound. During this time, the two developed a romantic relationship and were wed in late May 1863. Rejoining Lees army, which had just won a stunning victory at Chancellorsville, Ewell was promoted to lieutenant general on May 23. As Jackson had been wounded in the fighting and subsequently died, his corps was divided in two. While Ewell received command of the new Second Corps, Lieutenant General A.P. Hill took command of the newly-created Third Corps. As Lee began moving north, Ewell captured the Union garrison at Winchester, VA before driving into Pennsylvania. The lead elements of his corps were nearing the state capital of Harrisburg when Lee ordered him to move south to concentrate at Gettysburg. Approaching the town from the north on July 1, Ewells men overwhelmed Major General Oliver O. Howards XI Corps and elements of Major General Abner Doubledays I Corps. As Union forces fell back and concentrated on Cemetery Hill, Lee sent orders to Ewell stating that he was to carry the hill occupied by the enemy, if he found it practicable, but to avoid a general engagement until the arrival of the other divisions of the army. While Ewell had thrived under Jacksons command earlier in the war, his success had come when his superior had issued specific and precise orders. This approach was counter to Lees style as the Confederate commander typically issued discretionary orders and relied on his subordinates to take the initiative. This had worked well with the bold Jackson and the First Corps commander, Lieutenant General James Longstreet, but left Ewell in a quandary. With his men tired and lacking room to re-form, he asked for reinforcements from Hills corps. This request was refused. Receiving word that Union reinforcements were arriving in large numbers on his left flank, Ewell decided against attacking. He was supported in this decision by his s ubordinates, including Major General Jubal Early. This decision, as well as Ewells failure to occupy nearby Culps Hill, were later severely criticized and blamed in causing the Confederate defeat. After the war, many argued that Jackson would not have hesitated and would have captured both hills. Over the next two days, Ewells men mounted attacks against both Cemetery and Culps Hill but with no success as Union troops had time to fortify their positions. In the fighting on July 3, he was hit in his wooden leg and slightly wounded. As Confederate forces retreated south after the defeat, Ewell was wounded again near Kellys Ford, VA. Though Ewell led Second Corps during the Bristoe Campaign that fall, he later fell ill and turned command over to Early for the subsequent Mine Run Campaign. Richard Ewell - The Overland Campaign: With the beginning of Lieutenant General Ulysses S. Grants Overland Campaign in May 1864, Ewell returned to his command and engaged Union forces during the Battle of the Wilderness. Performing well, he held the line at Saunders Field and later in the battle had Brigadier General John B. Gordon mount a successful flank attack on the Union VI Corps. Ewells actions at the Wilderness were quickly offset several days later when he lost his composure during the Battle of Spotsylvania Court House. Tasked with defending the Mule Shoe salient, his corps was overrun on May 12 by a massive Union assault. Striking his retreating men with his sword, Ewell desperately attempted to get them to return to the front. Witnessing this behavior, Lee interceded, berated Ewell, and took personal command of the situation. Ewell later resumed his post and fought a bloody reconnaissance in force at the Harris Farm on May 19. Moving south to the North Anna, Ewells performance continued to suffer. Believing the Second Corps commander to be exhausted and suffering from his previous wounds, Lee relieved Ewell shortly thereafter and directed him to assume oversight of the Richmond defenses. From this post, he supported Lees operations during the Siege of Petersburg (June 9, 1864 to April 2, 1865). During this period, Ewells troops manned the citys entrenchments and defeated Union diversionary efforts such as attacks at Deep Bottom and Chaffins Farm. With the fall of Petersburg on April 3, Ewell was forced to abandon Richmond and Confederate forces began retreating west. Engaged at Saylers Creek on April 6 by Union forces led by Major General Philip Sheridan, Ewell and his men were defeated and he was captured. Richard Ewell - Later Life: Transported to Fort Warren in Boston Harbor, Ewell remained a Union prisoner until July 1865. Paroled, he retired to his wifes farm near Spring Hill, TN. A local notable, he served on the boards of several community organizations and also managed a successful cotton plantation in Mississippi. Contracting pneumonia in January 1872, Ewell and his wife soon became gravely ill. Lizinka died on January 22 and was followed by her husband three days later. Both were buried in Nashvilles Old City Cemetery. Selected Sources Civil War Trust: Richard EwellCivil War: Richard Ewell HistoryNet: Richard Ewell at Gettysburg