HUMAN IMPACT. Part 1. EUTROPHICATION & ACIDIFICATION

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1 HUMAN IMPACT Part 1. EUTROPHICATION & ACIDIFICATION

2 SUBSTANCES INORGANIC & ORGANIC

3 SUBSTANCES INORGANIC & ORGANIC Eutrophication Acidification

4 HUMAN IMPACT EUTROPHICATION

5 EUTROPHICATION water pollution caused by excessive plant nutrients

6 EUTROPHICATION Nutrients fall into three categories macronutrients, micronutrients, and trace nutrients

7 EUTROPHICATION Macronutrients: C, N, K, Ca, Mg, P, and S Micronutrients: Cl, Fe, B, Mn, Zn, Cu, Mo, and Ni The prefix "micro" is well-understood from its use in terms such as "microscope". The term "macro" is somewhat less common, but indicates objects of a somewhat large size. Intermediate sizes are sometimes indicated by "meso".

8 Nitrogen, phosphorus, and carbon species can exist in both organic and inorganic forms.

9 NITROGEN The most common inorganic forms of nitrogen are ammonia, nitrite, and nitrate. nitrate Total organic nitrogen can exist as particulate or nonparticulate organic nitrogen. Most of the nitrogen compounds in surface-water bodies exist in an oxidized form as nitrate and nitrite.

10 NITROGEN The U.S. Environmental Protection Agency (1986) has established water-quality standards or guidelines for nitrate, nitrite, nitrite plus nitrate nitrogen, and ammonia. Nitrate, nitrite, and ammonia in concentrations above established standards or guidelines can be detrimental to the health of humans, and ammonia is toxic to aquatic organisms.

11 PHOSPHORUS Phosphorus exists inorganically as soluble reactive phosphorus and in the particulate inorganic and nonparticulate inorganic states. Soluble reactive phosphorus is commonly referred to as orthophosphate. orthophosphate Particulate inorganic phosphorus consists mostly of phosphate minerals, such as apatite. Nonparticulate inorganic phosphorus includes condensed phosphates, such as those found in detergents. Phosphorus exists organically as particulate organic and nonparticulate organic phosphorus. Particulate organic phosphorus exists in plants, animals, and organic detritus. Nonparticulate organic phosphorus comprises mainly dissolved or colloidal organic compounds

12 TYPICAT CONCENTRATIONS SUFFICIENT TO PLANT GROWTH Element of atoms Nitrogen Potassium Calcium Magnesium Phosphorus Sulfur Chlorine Iron Boron Manganese Zinc Copper Molybdenum Nickel Symbol mg/kg percent N K Ca Mg P S Cl Fe B Mn Zn Cu Mo Ni 15,000 10,000 5,000 2,000 2,000 1,

13 EUTROPHICATION Nutrients exist in water bodies as a result of both natural and anthropogenic (manmade) sources, although contributions from natural sources are minimal. minimal Anthropogenic contributions might be significant, however, and can result from agricultural activities, domestic and animal waste, municipal wastewater, and byproducts of manufacturing processes.

14 EUTROPHICATION Phosphorus generally is lower in concentration than other nutrients because it does not naturally occur in the atmosphere nor is it abundant in the earth s crust. Phosphorus also tends to strongly adsorb to sediments and finegrained particles, causing its removal from the water column.

15 EUTROPHICATION Nitrogen differs from phosphorus in that it naturally occurs in the atmosphere and does not adsorb as strongly to particulate matter. matter Additionally, denitrification acts as a removal mechanism for nitrogen under anaerobic conditions.

16 Stoichiometry: Algae Growth Production of organic matter (say algae): 106CO NH4 + HPO H2O C106H263O110N16P O2 + 14H+ Mass ratios of C:N:P => 1272:224:31 and including 1% P in protoplasm, we obtain: 40:7.2:1 algae

17 In management it is often important to identify which nutrient used for plant nutrition controls the level of plants in water bodies: N and P: The Limiting Nutrient Comparison of nutrients in water to stoichiometry can show which nutrient is the limiting nutrient If the N:P ratio < 7.2, then N is limiting If the N:P ratio >7.2, then P is limiting

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20 EUTROPHICATION: physical changes chemical changes biological changes

21 physical changes

22 physical changes transparency, colour, smell (odour)

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24 chemical changes content in N and P compounds content in CH4, SO4, H2S, O2

25 biological changes

26 biological changes

27 HUMAN IMPACT ACIDIFICATION

28 KIEDY DESZCZ JEST KWAŚNYM DESZCZEM? Opad atmosferyczny jest zazwyczaj nieco kwaśny, gdyż dwutlenek węgla (CO2), występujący w sposób naturalny w powietrzu, rozpuszcza się w opadzie, tworząc roztwór kwasu węglowego (H2CO3), co obniża ph do 5,6. Dzieje się tak ponieważ kwas węglowy jest nietrwały i dysocjuje w wodzie tworząc jony hydroniowe i wodorowęglanowe: Kiedy ph opadów atmosferycznych spada poniżej 5,6 to mamy do czynienia z kwaśnym deszczem. Oprócz kwaśnego deszczu może też wystąpić: kwaśny śnieg czy kwaśna mgła, więc ogólnie możemy mówić o kwaśnych opadach.

29 ACIDIFICATION Acidification is the process whereby air pollution mainly ammonia, sulphur dioxide and nitrogen oxides is converted into acid substances. Burning of fossil fuels!

30 ACIDIFICATION This acid rain is best known for the damage it causes to forests and lakes. Less well known are the many ways it damages freshwater and coastal ecosystems, soils and even ancient historical monuments, or the heavy metals these acids help release into groundwater.

31 NEGATIVE EFFECTS Ca and Mg removal Aluminium is least soluble above ph 5 and is released from complexation with organic matter at ph 4.2. Acid rain may have a ph from around 4.5 down to 2.4 or less. High levels of [Al-] certainly can cause root damage.

32 NEGATIVE EFFECTS Acidification of water reservoirs when? 1. Low buffering capacities (lakes) 2. Small reservoirs

33 NEGATIVE EFFECTS Corrosion of pipes, equipment

34 NEGATIVE EFFECTS Solubulity of heavy metals in water increases as ph drops!

35 NEGATIVE EFFECTS Heavy metals are released form sediments and soil surrounding water reseroirs!

36 NEGATIVE EFFECTS SOIL DEPLETION: heavy metals are moving accumulation Ca and Mg are removed eutrophication

37 NEGATIVE EFFECTS HEALTH PROBLEMS

38 NEGATIVE EFFECTS BIODIVERSITY The Earth s ecological systems are of a dynamic character and reflect climatic conditions and geological, biochemical and biological processes over time.

39 NEGATIVE EFFECTS Each one unit increase in ph value represents a ten-fold increase in alkalinity BIODIVERSITY IN WATER AND SOIL COMPARTMENT

40 NEGATIVE EFFECTS koi prefer a range between 7 and 8.5, while some tropical fish prefer water that is slightly acidic There are several ways that ph can affect fish health High acidity or alkalinity can cause direct physical damage to skin, gills and eyes. Prolonged exposure to sub-lethal ph levels can cause stress, increase mucus production and encourage epithelial hyperplasia. Fish also have to maintain their own constant internal ph. Even small fluctuations of blood ph can prove fatal.

41 NEGATIVE EFFECTS CaCO3 + 2H+ ---> Ca2+ +CO2 + H2O CaCO3 + 2HNO3(aq) ---> Ca2+(aq) + 2NO3 - (aq) + H2O + CO2

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