1. SULFUR CYCLE Group 5Rey D. AbelitaWilliam ArcillaJesher Arsenio Emma Fernandez Issa Maslog

2. AN INTRODUCTION WHAT SULFUR IS Sulfur (Sulphur in UK) is a member of Group VIA->same as oxygen. Its name was derived from soufre, anOld French word which means to burn. Antoine Lavoisier-> Helped convinced the ScientificComm. That Sulfur = an element not a compound. Oxygen unlike Sulfur, is in the secondperiod, hence, no d orbitals. The d orbitals allows additional electrons to beaccommodated = six bonds instead of Oxygens twobonds. 3. AN INTRODUCTION SULFUR AND ITS IMPORTANCE In humanity, it is produced most specially in industries where it is used as solvent, catalyst and reactant to produce different organic compounds. (H2SO4) In ecosystems as a whole, no matter what form (SO 2, H2SO4, H2S), Sulfur in its soluble form ===>plants ==>series of metabolic processes. ( starts photosynthesis) ---> Sulfur-bearing amino acids. Sulfur -> Helps retain cellular structure; provides chemical links that creates collagen and keratin; Activator of minerals and vit.; Sulfur (in protein assembly and structure) bonds-> known as disulfide bonds- > plays an important role. Sulfur is also an important component of diff. enzymes such as coenzyme A, and of standard amino acids such as Cysteine. Producers -------> Consumers [Sulfur in Amino Acids] 4. Cysteine Coenzyme A 5. THE SULFUR CYCLE The sulfur cycle gaseous and sedimentary phases. As an introductory note -> The long term sedimentary phase, Sulfur is tied upin organic and inorganic deposits, released by weathering anddecomposition. The gaseous phase permits the circulation on a global scale. [to be expoundlater] Their main difference is in their exchange sites/ sites of occurrence.Sedimentary phase is mainly on the Earths surface (i.erocks, sediments, etc.) while the gaseous form is on the atmosphere. Reservoir: Oceans (aerosol/SO 4) ===> (CH3)2S, Atmosphere (SulfurDioxide, Hydrogen Sulfide and Sulfates) , Organic and Inorganic Deposits(Sedimentary Rocks, Igneous Rocks such as pyrite or FeS 2.) Exchange Pools: Hot Springs, Geysers, Surfaces of the Ocean,, Fossil FuelCombustion, Volcanoes, Decomposing Matter 6. SEDIMENTARY AND GASEOUS 7. Sedimentary cycle Weathering of rock and leaching of itsminerals, transport, deposition and burial. Gaseous Cycle A biogeochemical cycle with the mainreservoir or pool of nutrients in theatmosphere and ocean 8. SULFUR ENTERS THE BIOSPHERE THROUGH Natural ActivityCarried through Weathering of rocksterrestrial environments and decomposition in salt solution.Consumers Plants 9. SULFUR ENTERS THE ATMOSPHERE THROUGH Natural Activity Human Activity Volcanic Burning of fossil eruptions, gasesfuels, acidic drainage released by from minesdecompositionEnters atmosphere as H2S and reacts with oxygen to form SO2 10. SO2 is soluble inAcid rain (H2SO4)H2Oconsumersplants 11. Death of Sulfur to theconsumers atmospherePonds, lakes, seas and oceans soil 12. Different kinds of bacteria process this sulfurNon-photosyntheticphotosyntheticColorless sulfurPurple bacteria bacteria Green bacteria 13. Sulfur IronFerrous sulfide(FeS2) 14. Sulfur from theoceansReleased in the atmosphereas Dimethyl sulfide((CH3)2S )Go back to the atmosphereby bacteria fixation, or seasprays 15. GLOBAL SULFURCYCLE 16. Gaseous phase of sulfur cyclecirculates on a global scale. 300 x 1012 grams/year 17. Each flux is shown in units of 1012 grams S/year 18. Atmosphere Sulfur dioxide (SO2) Hydrogen sulfide (H2S) Sulfate Particles 19. Sulfate particles become part of drydeposition. (DRYFALL) Gaseous forms combines withmoisture and are transported inprecipitation.(WETFALL) 20. Oceans Large sources of aerosols that contain sulfate(SO4) Most are redeposited in oceans as precipitation and dryfall. Dimethylsulfide((CH3)2S) major gas emitted from oceans Estimated 16 x1012 grams S/year is emitted 21. Freshwater wetlands and anoxic soils Hydrogen sulfide (H2S) Forest fires 3 x 1012 grams/year Marine Plants 130 x 1012 grams/year Volcanic activity 10 x 1012 grams S/year 22. Eruption of Mt. Pinatubo(1991)release on theorder of 5 to 10 x 1012 gramsSulfur 23. Adding all anaerobicoxidation of organicmatter 200 x 1012 grams/year 24. Since the Industrial Revolution, humanactivities have contributed to the amount ofsulfur that enters the atmosphere, primarily through the burning of fossil fuels and theprocessing of metals. 25. What exactly are we doing? Burn sulfur-containing coal and oil toproduce electric power. Refine sulfur-containing petroleum tomake gasoline, heating oil, and otheruseful products. Convert sulfur-containing metallicmineral ores into free metals such ascopper, lead, and zinc. Mining erosion (exposure of mineralsulfides) 26. Emissions from these, along with nitrogen emissions, react with chemicals in the atmosphere SULFATE SALTS ACID RAIN Damage the natural environment(affects both plants and animals) aswell as man-made environmentsweathering/corrosion of buildings 27. Dry Deposition Gaseous sulfur dioxide component ofthe sulfur cycle and the nitrogen oxidesof the nitrogen cycle mix in theatmosphere. Some of this mixturereturns to the Earth as particulate matterand airborne gases, known as drydeposition 28. Effects For humans, it irritates therespiratory tract, from the nosethen moves into the lungs and attackssensitive tissues. High concentrations have caused anumber of air-pollution disasterscharacterized by higher than expecteddeath rates and increased incidencesof bronchial asthma. 29. Wet deposition Major portion of D.D. is transported away from thesource in a direction influenced by the atmosphericcirculation. During their transport, sulfur dioxide andnitrogen dioxide and their oxidative productsparticipate in complex reactions involvinghydrogen chloride and other compounds, oxygen andwater vapor. These reactions dilute solutions of strong acids (nitricand sulfuric acids). Eventually they come to earth inacidic rain, snow and fog. Sulfur dioxide combines with atmospheric moisture toform sulfuric acid which falls on land and water andforms significant part of acid rain 30. Effects Causes major damage to vegetation in areassurrounding the source of emission Injures or kills exposed plants Acidic aerosols present during periods offog, light rain and high relative humidity togetherwith moderate temperatures do the injury.External surfaces of theleaves absorb the aerosols.When dry, leaves and needles take up sulfurdioxide through the stomata. In the leaf, thesulfur dioxide rapidly reacts with moistureforming sulfuric acid. 31. Symptoms to sulfur damage are a bleached look to deciduousleaves and red-brown needs onconifers, partial defoliation andreduced growth. 32. Nutrient deficient soils Acid rain low pH level of soil nutrient leaching reduce solubility and availability (macronutrients) and high availability of micronutrients (Al, Fe, Manganese toxicity) inhibits fungal and bacterial activity reduce humus production, mineralization and fixation of nutrients 33. Low pH levelNutrientAcid Rain of soil leaching Affects activity ofLow: MacroHigh toxicitymicroorganisHigh: Micro ms Reduced humus Nutrientproduction, mineralization andnutrient fixation deficient soils 34. In water Sulfateand nitrogen ions replacebicarbonate ions, pH declines, andthe concentration of metallicions, especially aluminum, increases. Although adult fish and some aquaticorganisms can tolerate high acidity, acombination of high acidity and highlevel of aluminum can kill them. 35. Eggs and larvae of frogs andsalamanders are sensitive to acidicwater. Cause decline inamphibians/increased rate ofmortality. Acidic waters toxic to invertebrateseither killing them directly orinterfering with calcium metabolism(causing crustaceans to lose theability to recalcify their shells aftermolting) 36. Corrosive