Hydrological Cycle—change/recycling of water between atmosphere and hydrosphere Lecture Notes 2010

Lecture 4 Tuesday May 25, 2010 Hydrological Cycle—change/recycling of water between atmosphere and hydrosphere (water bodies) and water supply sources -helps to purify water -helps to evaporate fresh water into the atmosphere (helps purify atmosphere) -helps nutrients recycle -nitrogen oxide becomes part of rainfall or carbonic acid which falls to ground and water cycle helps to purify the atmosphere -subturanian water supply sources -use of fossil water resources -vegetation plays role in water cycle (i.e. leaf surfaces) -helps to moderate climate -oceans= carbon sink because absorbs concentration of gases Global Perspectives on water Sources of water supply -groundwater and streams -streams (affluent streams, influent streams- based on rainfall or precipitation, intermittent or irregular) -aquifers- source of water supply to many states in USA, rely on for food production -need certain conditions to exist (overlying layer of sandstone or permeable rock formation, underlying layer of rock formation-granite or clay layer – water is sandwiched between overlying permeable layer and underlying impermeable layer) -ability of them to supply water depends on the recharge capacity -can identify aquifier discharge and recharge -surplus- inflow of water exceeds outflow or deficit -precipitation- rain, snow, hail, icesheets etc. when the ground is oversaturated with water- excess run-off (can be part of streams) -wetlands (services and functions) – lacustrines, palustrines, estuarines Water Demand and Supply -agriculture- best way to manage water – provide drift irrigation system- construct canals or make channels to divert water costs – create a new terrain and water table (in places where already have water table , nothing seeps underground, will flow on surface)- so need for lining to cover entire canal to prevent evaporation into the atmosphere – only way for watter to be managed efficiently in agriculture sector -ratio between throw outs and consumption will give you wastage of water -domestic use- inefficiency in water use- more water evaporated into atmosphere in afternoon (heat and sun), toilets, dishwashers -closed systems keep water and recyle -open systems release water into environment after use -industrial and manufacturing use -dams, canals, and channelization- must prevent w ater seepage 1. Loss of water 2. salinization 3. Silting- can lead to growth of vegetation i.e. in river – can affect quality of water supply 4. erosion- seasonal flooding, places where most predominant regions where diverting rivers i.e. widening rivers water tends to erode 5. degradation of stream quality- ecosystems of rivers affected - 6. flooding Physical Contamination Sediment: sediment load into lakes rivers, particles of sand pebbles or rock fragment –result is that more particles are eroded and carried in suspension Heat: -comes mainly from industrial acivities i.e. nuclear power plants -hotter than temp in rivers and streams so cant go back into rivers or streams because will harm ecosystem biological contaminations- Water-borne diseases -fecal coliform bacteria- shouldn’t exceed 200 cells per 100 mL of water -outbreak of walkerton (e-coli) -outbreak of cryptosporidium- Milawaukee -cultural eurtophication in Lake Winnipeg should everyone stop using tap water and use bottled water? Bc contaminated water and people dying in the past? - both have bacteria that can be harmful -heat mixed with plastic water bottles= chemicals that can lead to breast cancer -cultural Eutrophication Accidents and Careless Cotamination Chemical Contaminations -trace metals, chemicals, i.e. PCPs, DDT (dichloro diphenyl trichloro ethane polychlorinated buphenyls)- don’t break down easily so remain in environment for long time- not biodegradabale can end up in great lakes spatial displacement contaminants from 1 region ends up in other region i.e. PCP’s end up in antarctic and temporal displacement pollution remaining in environment for a long time and build up accumulate over considerable amount of years -oil spills (1989- Exxon valdez oil spill in Prince William Sound) -acid mine drainage Exxon Valdez oil spill at prince William sound (Alaska) Point sources- come from identifiable locations i.e. pipe, municipal sewage system or drainage system -discharge of contaminants from specific locations -i.e. if you know what companies are responsible non-point soures -discharge of contaminants from numerous and dispersed locations -various or diversified sources (ubiquitous) from anywhere and EVERYWHERE -i.e. coming from different agriculture sources treatment of contaminated water -elimination of the source i.e. buried gas tank- identify – computer models to identify source or equipment identifying the pollution -monitoring-identify type of contaminants, where they are coming from and which direction they are likely to flow (direction contaminants will flow **important) – requires a lot of technical expertise -remediation a) bioremediation –divert contaminated water and treat it biologically before releasing it into streams and rivers – helps to break down organic material and pollutants b) chemical remediation – i.e. chlorine to municipal water treatment – carried out by designated government agency disposal of nuclear waste-constant threat to life and safety, transporting wastes are an issue from powerplant to dump site “NIMBY” because of risk it poses – inconclusive (no technical method available now) -not enough financial resources for research into management of nuclear waste septic tank disposal system-not associated with municipal sewage (separated from municipal sewage systems) - need to prevent spill or leakage into ground water -separates solids from liquids -aerobic breakdown of aerobic materials -expose it to atmosphere -anaerobic breakdown- some bacterias produced and introduce bacteria to water source will has the ability to remove waste from sludges wastewater treatment plants advanced method- uses various chemicals to treat water -breakdown residues chlorine treatment- potential to remove most pathogens (disease causing) Managing Water Resources Input Approach -this entails an increase in water supply via new water sources Output Approach -increasing efficiency of water usage -controlling contamination of existing sources -political issues play a major role -i.e. water being exported to USA from Canada -deals with efficiency of water use -important to establish monetary system- measure or record what has been used on a regular basis Managing Water Resources -boundary water treaties -international trade agreements on bulk water export -ontario Permit to take water programme -bi-national great lakes water quality management (agreement between USA and Canada)- trade related problems- should being part of a trade agreement – should that prevent national government of having total control of resources? -few processes /legal positions on use of water examples: -policy “prawl of propriation” –part of legal policy developed in western USA states that if someone was the 1st to have access to water resource they have the seniority claim to that resource policy “Rule of Capture” – relates to use of water related resources –do not have absolute control of resource unless you capture it (well or pumping station that brings water to your location to claim ownership/legal entitlement to ownership) ** multiple choice questions *what is point source pollution and non point * why and how policy treaties between USA and Canada for water * what is water security *water treatment methods *biological, chemical contaminations FISHERIES Video -What are the most productive fishing grounds in the world? most reached? Most come from unregulated fisheries from undeveloped countries -Georges Bank - Canary Islands (African waters) -Sicily -Gulf of Alaska (some of the most productive fishing grounds in the world) Different levels of threats to fisheries? Thank about population growth chemicals etc. Vast nets that sweep the ocean floor Fish cannot reproduce fast enough to keep up with evergrowing human population At a much greater rate and faster scale As larger fish disappear global fleet seeking smaller fish which are the prey of larger fish= further collapses Not all the fish caught are being brought to shore- millions of tones (bycatch) are discarded as waste - investing in larger and more powerful boats leading to overfishing- all the incentives for overfishing are there for it to happen -plankton- some scientists believe reason for decline in fish -Overfishing- sustainable fishing act- could be a lot stronger -bottom trawl- large net pulled along sea floor- steel plates drag along bottom + rock hopper for ground fish –vast areas of sea floor are being trawled- large % of animals that make up sea floor are destroyed -long line fisheries many miles of baited hooks kept under water for a period of time – can remove more fish than the species can bare -half the sword fish caught are juveniles that haven’t had the chance to reproduce long lining catches species that they don’t want- but kill -instrumentation for catching fish have become high tech - marline/billfishes are most depleted (bycatch) -sea turtles- endangered species- victims of long line hooks -catching juvenile fish - reckless fishing- populations of fish is decreasing -tonnara fish trap- forces blue fin tuna to swim towards trap -purse seine net – -increased market demand -shrimp farms consume more resources than they create- create a lot of waste and pollutants (not sustainable practice)- many species that are most highly sought after for farming require fish meal and therefore have to fish for the fish meal to feed the farmed fish What are the policies in place for sustainable fishing? -new England management policy council – open and close fisheries sustainable fishing act- reduce bycatch- directs fishing managers to identify and protect habitat that is essential to healthy fish populations marine reserves- allow fish to grow longer and larger- so produce many more eggs -individual fishing quarter (IFQ)- quarters can be bought and sold like private property - limited entry (individual permits)- not open to anyone who wants to fish commercially -limits the amount of gear that can be used -marine stewardship council- objective standards to certify fisheries that are well managed Demand for seafood increases but can oceans keep up? -oysters, muscles, talapia- can take pressure off of other fish because don’t require fish meal to be raised -scientists, fishermen and regulators, policy makers come together to decide and find solutions FISHERIES Conservation of marine mammals Whales- Japanese vessels in oceans taking almost every whale they find – whales are important (oils, lubricants, perfumes) Dolphins- -precautionary principle off shoot of the united nations agreement- good policy/principle on paper but in terms of practice- many challenges exist what should we do knowing some of the problems identified? To deal with declining fish levels? - marine reserve help to restock ocean (fisheries act) -technologies being used are killing fish -sustainable fishing - fish that don’t require fish meal -lobster protection policy -annual allowable catch -determine which vessles should use and how many fish allowed to catch positive component of tragedy of commons in fisheries- everyone can benefit –additional profit that every fisherman will derive (individual gain) negative component-the tragedy of the commons problem-open access= overgrazing , depletion of ocean, destruction of marine organisms how best can we reconcile the need for marine ecosystem for food and at the same time preserve the ecosystem? Can ban fishing in certain coastal areas- but fish migrate in the ocean and are caught anyways Current challenges of the fishing industry -intense exploitation of fish stocks- cheimicals and industrial pollutants, chemicals used in fishing (i.e. DDT), can detect schools of fish -ocean-atmospheric interactions –global warming has increased temp of ocean -there are uncertainties in marine and fresh water fisheries management- very little education and ignorance- need awareness creation for conservation -most marine and fresh waters have been fished to the brink of extinction – is fish farming/aqua culture an alternative to fishing directly from the ocean and why? Fish farming – east asia, Thailand, Bangladesh – protein and income for communities -selling farms to corporations- provides alternative sources of foods compared to dependence on the ocean (benefit) and way of creating jobs for local people -stimulates education