Xtra Note Environment

• Estimated 1.4 billion people hv no access to treated drinking water. • 2.9 billion people live in area having poor (or no) sanitation regarding water & sewage. • > 250 million new cases of waterborne disease/year. 10 million of them resulting in death, half of those death are among children under 5.

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The Ganges River is simultaneously used for drinking,washing,& disposal of sewage – a ‘norm’ in most underdeveloped countries.

Organic Waste • Human/animal wastes contain organic matter. • Other organic wastes sources=garden waste like leaves,grass & trash. • Organic waste-biodegradable • Decomposition=process by bacteria/detritus feeders consumes O2. • In cold water DO ~ 10 ppm , less in hot water • In air, O2 ~ 200,000 ppm (20%). • Even a moderate amount of org.matter decomposition will deplete water DO level.

BOD • Common water quality test – BOD (biochemical oxygen demand). • BOD=measurement of amount of organic matter, in terms of how much O2 will be required to break down organic matter (biologically/chemically or both). • Fish/shell fish die when DO drops below 2/3 ppm. • Typical raw sewage BOD ~ 250 ppm

Chemical Pollutants • Water= excellent solvent • Water-soluble Inorganic Chemicals (heavy metal:lead,mercury,cadmium,nickel etc.), acids from mine drainage (sulfuric acid), acid precipitation (sulfuric and nitric acid), road salts (sodium & calcium chlorides), anti-freezer (run-way at airport) • Organic chemical (petroleum product->major oilspill,pesticides,various industrial chemical like polychlorinated biphenyls (PCBs),cleaning solvents & detergents. • Generally, COD values are higher than BOD values. The reason is that BOD measures only the quantity of organic material capable of being oxidized, while the COD represents a more complete oxidation. • Typical COD values for domestic waste range from 200 500 mg/L.

Exxon Valdaz – Prince William Sound

Chemical Pollutants • Many of the chemical pollutants are toxic (even at low concentration) • Biomagnification – Through bioaccumulation.Fish (Predatory fish – King Mackeral, Shark, Sword fish, Tile fish /shellfish(oyster, blood cockle). • At high concentration, chemical pollutants can change the property of water bodies – e.g. Pollutants from acid mine drainage.

Biomagnification – the DDT example

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http://www.eelsinc.org/id62.html

Mining Leachates

Sediments • Sediments = Sand, silt & clay. • Erosion from farmlands, deforested slopes, overgrazed rangelands, construction sites, mining sites, stream banks & roads. • Different particle saiz flow at different rate.Clay & humus carried in suspension (block photosynthesis,clog gills & feeding structure). • Bedloads (sand & silts) gradually washed along the bottom. Constantly shifting, scouring effects, bury & smoother bentos, fill in hiding place. • Clay (negative surface charges) carries nutrient – eutrophication.

Pulau Sibu-Chalet project by Dato’ Sheikh Khadir Slope erosionCoconut Bay resort, Pulau Sibu, Johor

Abandoned resort on steep slope,

Nutrients • Nutrient=Essential inorganic chemical required by plant growth (N,P,K=macro-nutrient). • 2 most important aquatic nutrient = N,P (usually a limiting factor). • Most obvious point source = Sewage outfall. • Need special treatment to remove nutrient (especially P). • Most notorious NON-point source = agriculture (chemical fertilizers,manure,irrigation water,sludge & crop residue). • Other NON-point sources = GOLF COURSES, lawns & garden & storm drains.

The cry from Redang Reef Kawasan Hutan Paya Bakau Yang Ditukarkan Kepada Kegunaan Lain bagi Pulau Redang, 1989-1999

Laut China Selatan

Teluk Dalam

Scaring of slope – golf-course then airport

Berjaya Beach & Spa Resort, mouth of Sg.Redang

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Kuarters Kakitangan Berjaya Redang Beach Resotr

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Landasan Kapal Terbang

Kuala Redang

Padang Golf terbiar

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Kawasan hutan paya bakau 1999 W

Abandoned golfcourse use as construction storage

Kawasan hutan hilang 1989-1999

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Abandoned golf course reclaimed from mangrove forest

Eutrophication • Eutrophic = well-nourished = natural-process. • Human induced pollutants increased the scope & speed of eutrophication. • 2 types of aquatic plants –(1) Benthic plants, (2) Phytoplankton • Benthic plant-aquatic plants grow attached/rooted in the bottom.- 2 types = submerged aquatic vegetation (SAV) & emergent vegetation. • Phytoplankton = algae & chlorophyll-containing bacteria (cyanobacteria). • When nutrient ↑, phytoplankton ↑, sunlight ↓& SAV ↓.

Oligotrophic→Mesotrophic→Eutrophic • Oligotrophic = bottom visible beyond immediate shoreline. Good forested watershed holds N & P tightly. Lake has low nutrient level → limits phytoplankton grow → allow light penetration →support SAV which draw nutrient from bottom →support diverse aquatic ecosystem. • Eutrophic=Phytoplankton has high growth rate, duplicate in 24 hours. • Phytoplankton = clog water filters,foul taste,toxins.

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Algal bloom on eutrophic Lake Mendota (Southern Wisconsin). Photo from http://savanna.lternet.edu/gallery/ntl/ NTL_010004?full=1

Eutrophic lake in southwest England, impacted by nutrients in runoff from agricultural cropland and nutrient discharge from a small municipal sewage treatment plant (http://www.earthscienceworld.org/ima ges/search/results.html?Keyword=Agr icultural)

Eutrophication of Shallow Lake & Ponds • Shallow= less than 2 meter • Eutrophication increase SAV growth (up to 1 meter high), covering the whole water surface (obstruction) & ↑ BOD when plant die. • Natural vs. cultural eutrophication. • Combating eutrophication (1) solving the symptoms or (2) getting the root cause.

SAV, Tasik Bera. Photo from http://www.worldisround.com/articles/289246/photo7.ht ml

• Combating eutrophication (1) solving the symptoms or (2) getting the root cause.

(1) Solving the symptoms

• Chemical treatment (herbicides)-Copper sulfate & diquat for phytoplankton; Fluridone,glyphosate & 2,4-D for SAV. Herbicides toxic to fish, fish die →Depletion of O2. Cosmetic treatment – vegetation grows back as soon as herbicides wear off. • Aeration – speed up the breakdown of accumulated detritus,improving water quality,return of more desirable plant. Costly. • Harvesting-commercial mechanical harvester. Harvested weed makes good organic fertilizer. Costly, weed grows back because roots are left in the nutrientrich bottoms. Not taking out phytoplankton. • Drawing water down – dammed water body. Dry the lake to kill weed.

Getting The Root Cause • Long term strategy – reducing nutrient input. • (1) Identify sources of nutrients & sediments. Watershed study. 20/80 concept • (2) Concept of limiting factors – P most commonly limiting in freshwater system; N in marine system.

Controlling Strategies for Point-Sources • Discharges from sewage-treatment plants.P level higher if laundry detergents containing P are used. • Key step is to ban the sale or regulate the maximum allowable level. Usually dishwashing detergents contains higher P. • Upgrade sewage treatment plant to remove N & P.

Controlling Strategies for NON-point sources • Best Management Practices (BMP)-Soil conservation with vegetated covered ground,strip cropping,legumes for natural N addition, organic fertilizers. • Reestablishment of riparian (river) woodlands (river buffer zone)-filtering & absorbing nutrients. • Recycle animal wastes – Integrated manure & organic waste management system

(http://unapcaem.org/Activities%20Files/A01/Integrated%20Manure%20and %20Organic%20Waste%20Management%20Solution%20%E2%80%93%2 0The%20Ruegen%20Demonstration%20Biogas%20Project,%20Germany.p df)

Riparian Buffer Zone

Kuala Lumpur river junction

Bear Creek, Iowa (http://www.iowadnr.gov/forestry/bufferphotos .html

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(http://www.mit.jyu.fi/tt/photo/ seasia1997/pictures/kl05.ht ml)

Controlling Strategies for NON-point sources • Urban/sub-urban area-3 to 5 time more fertilizer and pesticides used by homeowner. • Pet manure • Golf course-fertilizer, soil compaction thus promoting runoff. • Retention pond at construction sites.