2. Inorganic Nutrients
- are chemical compounds produced by a
variety of sources, many of which also
release organic nutrients
- two most common inorganic nutrients are
N & P
- Inorganic nutrients tend to promote
growth of aquatic plants
3. Where do inorganic nutrients come
from?
- runoff from fertilized lawns/croplands
- animal & human wastes (septic tanks)
- laundry detergents (tripoly-phosphate)TPPs
- distribution pipes
- industrial discharges
- weathering process
- atmosphere
4. Harmful effects of inorganic nutrients
in water bodies
- stimulates excess plant growth which
accelerates eutrophication
- can cause hypoxia (low D.O) which can harm
aquatic organisms
5. Nitrates
- a form of nitrogen which is found in several form in
terrestrial & aquatic ecosystems
- forms include ammonia (NH3), nitrates (NO3), and
nitrites (NO2) which occur naturally in plants
- used as oxidizing agent, in explosives & in food
- secreted in saliva & converted to nitrite by microflora
- when nitrite is combined w/ Hb, it forms
methemoglobin ( has reduced oxygen-carrying
capacity)
8. Phosphates
- occur in living & decaying matters
- as free ions bounded to aqueous systems,
sediments and soils
- mineralized compounds
- exist in 3 forms: orthophosphate,
polyphosphate & organic phosphate
- used in detergent formulations as water
softeners
- used extensively in the treatment of boiler water
14. Other methods of analysis used
- Surface-enhance Raman Spectroscopy) SERS
- Titanous chloride
- Hydrazine reduction
- Cadmium Reduction Method
15. Bruckner, M. Z. (2015, June 14). Microbial Life Educational Resources-Ion Chromatography. Retrieved from www.carleton.edu:
http://serc.carleton.edu/microbelife/research_methods/biogeochemical/ic.html
Chiras, D. D. (2001). Environmental Science 6th Edition. Ontario: Jones & Bartlett.
Department of Health. (n.d.). Philippine National Standards for Drinking Water 2007. Retrieved from www.lwua.gov.ph:
http://www.lwua.gov.ph/downloads_14/Philippine%20National%20Standards%20for%20Drinking%20Water%202007.pdf
Filippelli, G. M. (n.d.). The Global Phosphorus Cycle. Retrieved from www.agci.org:
http://www.agci.org/dB/PDFs/09S2_GFilippelli_GlobalPCycle.pdf
Marina Cavaiuolo, A. F. (2014). Nitrates and Glucosinolates as Strong Determinants of the Nutritional Quality in Rocket Leafy
Salads. MDPI, Nutrients.
Oram, B. (2014). Phosphate in Water. Retrieved from Water Research Center: http://www.water-
research.net/index.php/phosphate-in-water
Shashikanth Gajaraj, C. F. (2012). Quantitative detection of nitrate in water and wastewater. Environ Monit Assess, 5673.
United States Environmental Protection Agency. (2012, March 6). Water: Monitoring & Assessment. Retrieved from www.epa.gov:
http://water.epa.gov/type/rsl/monitoring/vms57.cfm
World Health Organization. (n.d.). Water Sanitation Health. Retrieved from www.who.int:
http://www.who.int/water_sanitation_health/dwq/chemicals/nitratenitrite2ndad
Works Cited
Notes de l'éditeur
*nutrients can be organic or inorganic
*whereas organic nutrients can stimulate the proliferation of aquatic bacteria
*distribution pipes have nitrates formed by bacteria during stagnation of nitrate-containing pipes
How to reduce surface runoff in farmlands
>smaller amounts of fertilizers to be used
> terracing
> strip cropping
Inorganic nutrients can be a limiting factor to the ecosystem
Eutrophication- enhanced production of primary producers resulting in reduced stability of the ecosystem
Excessive inputs of nitrate & phosphate
Aerobic conditions- natural cycles may be more or less in balance until an excess of nitrate/phosphate enters
- water plants & algae begin to grow rapidly
- excess die off of plants & algae as sunlight is blocked
- bacteria decompose consuming oxygen & releasing more phosphate
Anaerobic conditions- oxygen is used up through decomposition
- different bacteria continue to carry on decomposition and products are drastically changed such as C is converted to methane gas instead of CO2, S to hydrogen sulfide
*common inorganic pollutants of water
*nitrate can be converted to nitrite (toxic form) in the intestines of human
the Fe2+ present in the haem group is oxidized to its Fe3+ form, and the remaining nitrite binds firmly to this oxidized haem. The Fe3+ form does not allow oxygen transport, owing to the strong binding of oxygen which can lead to cyanosis (blue skin discoloration or blue baby syndrome)
*nitrate is taken up by plants during growth & synthesis of organic nitrogenous compounds (assimilation). Surplus moves to ground water
the uptake of nitrate by plants is responsible for most of the nitrate reduction in surface water
pH of water affects the conversion of nitrogen to ammonia (NH3 for more basic & NH4+ for more acid waters)
nitrification facilitated by autotrophic bacteria
denitrification facilitated by heterotrophic bacteria
BOD (food)+D.O or Nitrate if D.O (anoxic) is unavailable>>>>N2+OH-+energy
Importance of phosphorus
Key elements necessary for growth of plants and animals
Backbone of Kreb’s Cycle & DNA
*not toxic to humans and animals unless present in very high levels (digestive problems)
* Ion chroma- measures concentration of ionic species by separating them based on their interaction w/ a resin. Ion species separate differently depending on species types & size
Vernier Nitrate- measure the concentration of nitrate ions in aqueous samples
Capillary Ion Electrophoresis- separates ions based on their electrophoretic mobility with the use of an applied voltage. It gives faster and high resolution separation.
Phosphorus analyses embody 2 general steps:
Conversion of the phosphorus form of interest to dissolved orthophosphate (digestion method)
Colorimetric determination of dissolved orthophosphate
SERS- used by Gajaraj, et.al, 2012 in their study on quantitative detection of nitrate in water & wastewater, involved in measuring the inelastic scattering of light caused by molecular vibrations
Cadmium Reduction Method- colorimetric method that involves contact of the nitrate in the sample w/ cadmium w/ causes nitrates to be converted to nitrites. Nitrites then react w/ another reagent to form a red color whose intensity is proportional to the original amount of nitrate.