BIOGEOCHEMICAL CYCLING EXAMPLES Unit 6 2 BIOGEOCHEMICAL CYCLING

BIOGEOCHEMICAL CYCLING EXAMPLES Unit 6. 2

BIOGEOCHEMICAL CYCLING EXAMPLES 1) Nutrient Pollution 2) Agricultural Importance 3) Phosphorus and Nitrogen 4) CZ Function and Dynamics

Nutrient Pollution • Definition: The addition of excess nutrients, mainly nitrogen and phosphorus, into the water or air. • EPA claims that “nutrient pollution is one of America's most widespread, costly and challenging environmental problem. ”

Nutrient Pollution Effects • Environmental effects – Toxic Algae Blooms – Dead Zones/Hypoxia • Economic effects – Treating Impaired Drinking Water – Tourism Losses – Property Value Decreases • Human health effects – Nitrate Toxicity; Especially Impacts the Young and Old (e. g. blue baby syndrome) – Decreased Air Quality – Exposure to Toxic Algae

Nutrient Pollution Around the World • This World Resources Institute identified 762 eutrophic and hypoxic coastal systems impacted around the world • Between 1970 and 1990 over 20, 000 cases of serious waterborne infections were reported each year because of harmful algal blooms along the coast of the Black Sea. In addition over $2 billion (USD) worth of fish catch was lost due to eutrophication and a half-billion in tourism damage resulted • In the sea of Japan, a huge boom of Nomura’s jellyfish, occur every summer as they feed on the abundance of plankton which result from the increased nutrients. The jellyfish impact commercial fisheries by competing with fish for food and fowling boat motors and nets

Nutrient Pollution Causes • Wastewater – Sewer/septic systems • Urban – Stormwater, Yard Fertilizers/Waste, Pet waste, and Phosphate Containing Detergents • Agriculture – Soil, fertilizer, and manure runoff and infiltration Photo: NOAA

Agricultural Importance • Nutrient Management – Proper application and timing of fertilizer – Control livestock and irrigation waste – Conservation tillage • Soil Management – Install buffers – Plant cover crops Photo: Martin Pettitt

Agricultural Wastewater • The California Agricultural Water Stewardship Initiative defines agricultural wastewater as the excess water that runs off a field at the low end of furrows, border strips, basins, and flooded areas during surface irrigation • Water running of fields often has high concentrations of pesticides, herbicides, nutrients and other chemicals that could pollute surface or ground water • Capture and reuse of agricultural wastewater is a good example of a best management practice or BMP

Major Nutrient Pollution Elements NITROGEN PHOSPHORUS Primary Water Impacts Groundwater & Nearshore Ocean Freshwater systems only Primary Agricultural Sources Fertilizer Manure Can Exist as a Gas YES NO Cycling Characteristics Air, Water, and Soil Water and Soil Important Compounds Nitrite, Nitrate, Ammonia, and Ammonium Phosphate

CZ Function and Dynamics • Impacts of hydrology on a given area – Infiltration – Runoff • Environmental impacts and physical characteristics impacting weathering of minerals and soils – Soil creation – Nutrient transformation