Geography - Option A: Freshwater

systems theory (open and closed systems)

systems theory (open and closed systems)

systems: any set of interrelated components connected together

closed: system shut off from surrounding environment, self-contained (e.g. Earth, hydrological cycle)

open: system not self-contained, inputs of energy and matter flow into the system and outputs of energy and matter flow out of the system (e.g. city, river, car)

hydrologic cycle

the movement and interchange of water btwn sea, air, land

Water is constantly moving

transpiration

evap from plants where water vapour escapes

runoff

water flowing over land surface

infiltration

water soaking into the ground

infiltration capacity

max rate at which rain is absorbed by soil in given condition

percolation

liquid slowly passing through a filter

drainage basin/water shed

the geographic area which supplies water to the network of streams, lake, ocean

tributary streams carry water downhill and join to create a larger river

drainage divide

elevated ridge btwn 2 drainage basins

precip and evap

precip: conversion and transfer of moisture in atmosphere → land (rain/snow)

evap: conversion of liquid and solid precip to water vapour in atmosphere (energy provided by solar radiation)

overland flow

surface run-off water that flows over land’s surface when infiltration capacity reached

throughflow

water that flows through soil in natural piipes and percolines

baseflow

river discharge from groundwater that seeps into river bed

aquifers

permeable rocks that absorb water slowly (limestone, sandstone

cyrosphere

snow and ice environment

discharge (q)

volume of water passing through a cross section of a river during a given period of time (cubic m/s or cumecs)

thalwag

fastest point in a river

erosion

the breaking down and transport of sediment

hydraulic radius

ratio of cross-sectional area divided by perimeter of flow channel

Measures stream efficiency where high ratio = high efficiency and low frictional loss

abrasion, attrition, corrosion

abrasion: wearing away of bed and bank by load carried by river

attrition: wearing away of load carried by a river → smaller, rounder particles

corrosion: removal of chemical ions, rocks dissolve in acidic water

Flood plain

Area formed by deposition when river floods

Meandering

Normal behaviour of fluids and gases in motion

Levees

Raised banks at river edge formed by repeated flooding of river w/ deposition of material

(Flood/storm) hydrograph

Shows variations in a rivers discharge over a period of time

Drought and absolute drought

Drought: extended period of dry weather → extreme dryness

Absolute drought: 15 consecutive days w/o 0.2mm of rainfall

Phreatic and aeration zone

Phreatic zone: permanently saturated zone within solid rock and sediment where all pores are filled w/ water

Aeration zone: area that is seasonally wetted and seasonally dries out

Aquilude/aquifuge and aquitard

Aquifuge/aquilude: rocks that will not hold water like clay

Aquitard: layer of rock which prevents movement of water

Algal blooms

Rapid growth of algae from additional resources

Irrigation

Artificially adding water to farmland to boost plant growth

IDBM

Process of coordinating conservation, management, development of water+land

Maximize economic and social benefits from water wile preserving and restoring freshwater/resources

Wetlands and broads

Wetlands: area of land covered by shallow water or saturated by water most of the year

Broads: large, shallow sheet of freshwater - form of wetland

The drainage basin as an open system w/ inputs, outputs, flows, and stores

Flows

• infiltration and percolation

  • Influenced by rain duration, soil moisture and porosity, slope, vegetation

  • Infiltrated water is chemically rich (picks up organic and minerals)

  • Plant roots are channels for percolation

• Overland flow

  • When precip is greater than infiltration rate / soil is saturated

  • Increases when precip increases and infiltration capacity decreases (semi-arid, cultivated fields)

• Through fall

• Base flow

Storage

• freshwater storehouses: glaciers and icesheets (cyrosphere), rivers and lakes, atmosphere, vegetation, surface, soil moisture, groundwater channel, aquifers

• Saltwater storehouses: ocean

The distribution of water on earth

When ice melts/breaks off and enters sea, it changes the balance of fresh and saltwater → rising sea levels, water insecurity, less freshwater

Saltwater can not be used

The importance of rivers

Provide water and nutrients for agriculture

Provide habitat to divers flora and fauna

Provide commerce routes

Provide recreation

Provide electricity

Relationship between river discharge and stream flow

Increased flow = increased discharge

Water flow influenced by gravity (causes downstream flow) and friction (w/ bed and bank, opposes downstream flow)

Stream flow is turbulent, not steady, bc of complex channel shapes (meandering), high velocity, and cavitation

Relationship between discharge and stream characteristics

Velocity

• Downstream = high pressure + velocity (bc many smaller rivers join)

• Steeper = high velocity (bc gravity)

• Friction = uneven distribution of velocity (slowest near bed, fastest near centre)

Channel shape

• hydraulic radius

• Shape determined by material

  • Silt/clay = steep, deep, narrow valleys

  • Sand/gravel = wide, shallow

Channel roughness

• smooth = carry more water

• Friction from irregularities in river bed, trees, vegetation = low velocity

Channel size

• wide and deep = higher discharge

Stages of rivers

Upper, middle, lower course

Discharge, width, depth, velocity, load increase downstream

Channel roughness, load particle size, slope angle decrease downstream

Stages of river development

Youth stage

• V-shaped valley

• Fast moving water

• Erosion and turbulence

• Little deposition

• Rapids, waterfalls, boulders

Mature stage

• vertical erosion continues but lateral erosion evident (wider)

• Meanders and flood plains

• Water velocity slows

• Deposition

Old stage

• flood plain widens

• Natural levees

• Extensive meanders

• Oxbow lakes

• Developed river delta

River processes of erosion and the spatial and temporal factors influencing their operation (channel characteristics and seasonality)

Erosional action of rivers

1. Hydraulic action

   • water loosens and moves material

   • High velocity = high erosion

2. Abrasion

   • debris is abrasive → smooth beds and banks

   • High velocity = high abrasion

3. Attrition

   • rocks strike one another into smaller pieces

4. Corrosion

   • influenced by [solute] of water, discharge, velocity

Factors affecting erosion

• load: heavier and sharper = more erosion

• Velocity: higher = more erosion

• Gradient: higher = more erosion

• Geology: soft unconsolidated rocks (sand, gravel) easily eroded

• PH: more acidic = more erosion

• Human impact: deforestation, dams, bridges = more erosion

River processes of transport and the spatial and temporal factors influencing their operation (channel characteristics and seasonality)

Ways rivers transport sediment

• solution (dissolved)

• Suspension (dirty water, smallest particles)

• Saltation (larger particles bounced downstream)

• Traction (pebbles, roll downstream)

• Floatation (leaves, carried on surface)

Relationship btwn river velocity and particle size )Hjustrom curve

River processes of deposition and the spatial and temporal factors influencing their operation (channel characteristics and seasonality)

Deposition caused by shallowing gradient → decreased velocity, energy, volume + increased friction btwn water and channel, human activity like dam

How does seasonality affect river processes

Precip affects velocity and amount of water

River processes are based on amount of water/velocity

E.g. more water in spring bc melt

the formation of meanders

Meanders occur when channel slope, discharge, and load make a situation where it is the only way a stream can spread its energy over channel length

Meander becomes more pronounced as streamline shifts btwn river banks

May form oxbow lake

The formation of flood plains and levees

When river floods speed decreases bc vegetation on flood plain

River deposits load - heavy first and closest, then lighter last and further

The formation of sand bars

The formation of deltas

When stream flows into standing body of water, may form delta

Meeting btwn ocean and river

Sea erodes deltas, river deposits load bc decrease in velocity

Types:

1. Arcuate (e.g. Nile River)

   • many distributaries that carry water and sediment

   • Inverted cone shape

2. Birds Foot (e.g. Mississippi River)

   • Many distributary channels branch out from main river channel

3. Estuarine (e.g. Vancouver delta)

   • least common

   • Forms when river sediment deposited in submerged river mouth

The formation of waterfalls

Formed when layers of sediment erode at diff rates (e.g. limestone vs. Sandstone)

Soft rock undercut by hydraulic action/abrasion

Weight of water and lack of support → waterfall collapses and retreats

May retreat to form gorges/ recessions

Formation of river terraces

Formation of braided stream/river channel

Hydrograph characteristics and natural influences on hydrographs

Peak discharge: time of max discharge (higher in large basin)

Lag time: period of time btwn peak rainfall and peak discharge (influenced by basin shape, steepness)

Falling limb: period when river discharge is falling

Normal flow: river’s base flow, slow movement + long-term supplier of Q

Rising limb: period of rising discharge following period of rainfall, indicates amount of Q and speed it is increasing (steep in flash flood, small drainage basins, urban areas)

Peak rainfall: the hour of greatest rainfall during storm

Hydrograph size: area under graph (high rainfall and basin size = high Q)

Factors affecting flood hydrographs

climate: rainfall total, rainfall intensity, évapotranspiration

Vegetation cover: intercepts rainfall so flood less likely

Soil: clay soils → overland flow → more flood, sharp hydrograph

Infiltration capacity: sand, soil, big rocks, clay, etc have diff ability to hold rainfall

Rock type: permeable rocks allow more water to infiltrate

Slope angle: steeper slope = greater runoff and less infiltration, flat = more infiltration, more through flow, lower hydrograph peaks)

Drainage density: more stream channels = more water into rivers

Basin size: shape and relief/slope - small, steep basins = less lag time

Human activity:

• more impermeable surfaces and additional drainage channels increases flood risks

• Dams disrupt flow

How do floods happen

Floods happen when river can no longer contain water it is transporting in its channel

Water flows out of channel to flood plain

Small floods contained on flood plain close to river

Large floods are less frequent but cover more flood plain

Factors affecting flood risk

How urbanization, deforestation, and channel modifications affect flood risk within a drainage basin including its distribution, frequency, and magnitude

Urbanization (Urban vs. Rural hydrology)

• urban areas have shorter lag time, steeper rising limb, higher peak discharge, steeper recessional limb

• Causes

• - more impermeable surfaces (roads, buildings, pavements, roofs) → lower absorption rates and more overland flow

• More drainage channels (gutters, drains, sewers) → increased drainage density

• Natural rivers constricted by bridge supporters/riverside facilities → less carrying capacity

Deforestation (from land-use changes like agriculture, development)

• vegetation increases interception, decreases overland flood, increases évapotranspiration - deforestation has the opposite effect

• Hydrograph has shorter lag times, higher peak flows

• Vegetation loss → higher flood risk

• Tree removal → erosion and deposition in channel → artificial dam that decreases channel capacity and increases flood run-off

Channel modification

• straightening

  • Water moves faster and is removed from an area quickly

  • Only mitigates - flooding at end

• Channelization

  • Create new flood-relief channels

  • only mitigates - flooding downstream

• Levees/dikes

  • Enlargers channels and increases river bank height → increased carrying capacity

  • Divert and restrict water to low-value land on flood plain

• Widening and deepening

  • Increases carrying capacity

• Dredging

  • Remove sediment from bed

  • Increases carrying capacity

Attempts at flood prediction

Flood forecasting and warning has become more accurate (satellite, radar)

Making warnings available to ppl is easier bc television, phones, computers

Forecasting can be used to reduce problems caused by flooding

BUT there are problems

• not much flood warning time

• LICs have much less effective forecasting

• Poor have least access to new tech and info

• GCC = uncertainty in climate modelling bc erratic rainfall, frequent floods

Flood mitigation through structural measures

Dams

• control river flow by holding back water during flood and releasing when risk is gone

Afforestation

• increased interception, less erosion, less overland flow → reduced risk

• Initially may increase bare ground from overland run-off, decreased ground vegetation, young trees, tractor routes

Channel modification

• raising banks, straightening, channelization, artificial levees, dredging

Flood mitigation through planning

Personal insurance + Loss sharing

• Disaster aid (money, equipment, staf)

• Insurance in HICs (but not all have it and often underinsured)

Flood preparation

• Use sandbags to protect home

• Seal doors and windows

• Move valuables upstairs

• Move electrical generators to building tops

• Design homes so electrical features higher than expected flood levels

CASE STUDY: Flood mitigation in Thames River, England

Thames is longest river in England, drains entire Greater London area

2014 major floods Bc increased precip and storms

• groundwater build up

• Rivers reaching full capacity

• Artificial channel diverted water further downstream but severe flooding downstream

• Power less, deaths, evacuation

Flood mitigation

• planned new additional channels (didn’t happen)

• Improved existing channels

• Installed property-level products

• Better flood response plans

CASE STUDY: Dam in Nile River, Egypt

Nile river important for agriculture

Aswan High Dam build → irrigation, power source, farming land

Undesirable side effects

• flooding of temples and statues (tried to bury w/ sand, build wall, move temples)

• Decreased flood → less fertile land + reliance on imported fertilizer

• Increase SA → water lost to evap

• Erosion

The 3 components of water scarcity

Water shortage: when water quality declines over time bc dynamic factors like climate change, pollution, increasing demand for water

Water stress: when water demand exceeds amount available/when poor quality of water restricts its usefulness

Water crisis: when supplies of clean, usable water cannot support sufficient food production/other legitimate domestic industrial, environmental needs

Factors causing deterioration of water quantity

Water is a finite resource

Volume of water available does not change but increasing ppl want to use it

Therefore quantity of water/person is decreasing

Factors causing deterioration of water quality

Pollution - sewage, factories, agricultural runoff, garbage

Turbidity - cloudiness from stream erosion

Siltation + sedimentation - erosion of hill slopes

Salinity - over irrigation of agricultural fields

Bacterial disease - animal manure

These can be affected by over-use, excessive extraction of groundwater, political conflict, lack of infrastructure investment

Physical vs economic water scarcity

Causes and impacts of drought

Causes: seasonal/weather events

Impacts:

• decreased crop yield (heat)

• Mortality (elderly)

• Illness (water quality)

• Forest fire (uses water)

Stakeholders in the environmental consequences of agriculture on water

Farmers (apply fert for increased yield)

Chemical companies (make fert)

Oil and gas companies

Government (try to achieve food security)

Customers (rely on food supply and availability)

Water companies (provide water to consumers)

Citizens (responsible for clean up)

Environmental consequences of agriculture on water (irrigation)

• benefits: increase productivity → increase food availability, decrease food prices, increase employment, faster agricultural/economic development → world wide crop production heavily dependent

• Consequences:

  • Less downstream flow bc removed from river

  • Water lost to groundwater store/atmosphere when added to fields

  • Salinization

    • Excess surface water from over irrigation → water passes over soil and dissolves salt + waterlogging (water table rises) frees up salt to rise → encourages evap which leaves salt in soil

    • Soil is not good for cultivation, destroys plumbing appliances, salt water not drinkable

    • Excess irrigation water tuns off into streams and carries salt downstream

Environmental consequences of agriculture on water (eutrophication)

Causes:

• farms use ferts to increase productivity

Consequences:

• fertilizer runs off and increases nitrogen in water

• Algae grows quicker w/ nitrogen → blooms

• Blooms cover reservoir so no light let in

• Algae consumes oxygen → anaerobic conditions → organism death

• Kills water source (still lakes)

• Decreased water quality → scarcity

Solutions

• decrease nitrate ferts

• Educate farmers

• Remove anaerobic mud from lake

Environmental consequences of agriculture on water (clear cutting)

Soil creeping down → landslide → turbidity and siltation

Can’t drink water bc organic materials

Environmental consequences of agriculture on water (pesticides + herbicides)

Consequences:

• Don’t meet target species

• Build up in soil/water

Solutions

• Regulations for biodegradable pesticides

• Biological pest controls

CASE STUDY: poor water management in the Aral Sea, Kazakhstan + Uzbekistan

Sea shrinking and drying up

Causes:

• cotton farming

  • Was major cotton growing region of USSR

  • Irrigation needed to grow cotton in desert

  • Dams and canals diverted water to cotton farms → less water reaching sea

• Deteriorating water quality

  • Sea → saltier bc evaporation

  • Industry pollution from fert, insecticide, herbicides applied to cotton returning to river w/ irrigation water and into sea

Impacts

• affect wildlife (fishing industry)

• Wells dried up bc water table dropped

• Unemployment and migrate away

• health problems (chemical seepage into water supply)

Future implications

• international cooperation needed

• Pops need safe drinking water

• Consider sustainability of cotton growing

• Redesign irrigation system

CASE STUDY: Water scarcity in Colorado River, Mexico + USA

Physical water scarcity bc dry climate

Growing urban pop → increasing water demand

Farmers want to grow crops w/ irrigation (bc warm climate and increasing demand)

• high demand in area of scarcity → international tensions btwn Mexico + USA

• Increased water use → river dries up before reaching sea

• Irrigation runoff (overirrigation) → salinity and poor water quality

Mexico gov complained

US agreed to address water quantity problem, but Mexico pushed new agreements about water quality (salinity)

Colorado RIver Compact signed but did not consider Mexico’s needs

Growing human pressures on lakes and aquifers affecting groundwater management

Distribution of water changing bc GCC

Pop + economic growth → increasing demand

Aridity + heat → physical water scarcity

Groundwater is used by humans through extraction and storage - draw an aquifer

Groundwater is used by humans through extraction and storage - draw an artesian aquifer/basin

Artesian aquifer: confined aquifer containing groundwater under positive pressure, causing water level in a well to rise to a point where hydrostatic equilibrium reached

Artesian basin: large artesian aquifer (e.g. Great Artesian Basin, Australia)

How do aquifers/artesian aquifers recharge

Natural: hydrologic cycle

Artificial: water pumped into aquifer down bore holes or recharge basins (large reservoirs w/ porous bottoms so water seeps into aquifer)

Importance of lakes and ponds and the increasing pressure placed on them

Importance

• Biodiversity (habitats and breeding)

• Water cycle (protect from flood, recharge groundwater)

• Human use (agriculture, industry, domestic, recreation)

Pressure

• pop growth and economic development → pressure on water quality

• Chemical pollutants, sewage, aggro-chemical flows of pesticides and ferts

• Irrigation → lakes drying up

• Climate change → changes in distribution + timing

Impacts of groundwater abstraction

Causes of conflict from internationally shared water resources

There are many trans-boundary river basins + aquifers → potential for conflict

Water quality problems can escalate to disagreements over shared resource

Water scarcity - water access needed to survive and another country restricts

Large-scale water developments → conflict w/ neighbouring countries + internal conflict bc displacement of communities

Climate change → increased temps and evap loss and droughts and floods → scarcity and need to build water developments → tensions

What factors make conflict over internationally shared water resources more likely

Degree of water scarcity

Extent to which a water supply is shared

Relative power of countries sharing it

Access to alternative supplies

CASE STUDY: conflict over internationally shared water resource Nile River

Egypt highly dependent on Nile

Upstream countries need it too - Sudan needs to increase food production but faces water scarcity

Egypt and Ethiopia unwilling to negotiate w/ Sudan

Methods to decrease potential conflict over water resources

Follow international law (e.g. UN treaties)

Equitable utilization - each country entitled to reasonab;e share

Avoid causing harm to other countries

Notify and inform of actions on shared rivers

Share data

Work together to manage resources

Resolve disputes peacefully rather than war (requirement of UN charter)

CASE STUDY: conflict over internationally shared water resource Indus River Basin

Flows through China, India, Afghanistan, Pakistan

Important for agriculture, drinking, industry, hydroelectricity, transport, fishing, tourism

River causes conflict btwn India and Pakistan bc both want ownership

• Indus Water Treaty to negotiate

• World Bank involved to help economic

The problem of water supply is from many interacting factors such as…

Uneven distribution

• rainfall + runoff high in some places low in others

Retention and distribution of water consumes many resources

• cities need to build dams and pipelines

• Semi-arid rural communities need indifidual effort and time to dig wells and transport water

Most of the world’s water is inaccessible/difficult to access

Do water management issues differ in LICs and HICs

Water management issues differ bc of degree of water scarcity/excess, culture, economic health

much of the responsibility to manage water falls on local communities - community actions to manage water in LICs vs HICs

Most efforts to manage water focus on first-time water use. Explain the significance of reusing and recycling water

Industry and modern lifestyle waste lots of water that can be recycled

But costs of water too low to be incentive for recycling, and cost of tech to purify water is too expensive

Water scarcity is increasing so ppl must become better at preventing water pollution and be ready to pay for water treatment

Why are dams built

Flood and drought control

Irrigation (agriculture and oil)

Hydroelectricity power

Improved navigation (control river depth)

Recreation and tourism (boating and fishing)

Domestic and industrial water supply

Benefits of dams

Economic development from increased agriculture and other activities

Hydroelectricity is clean energy

Water supplies secure and reliable

Local employment

Less flood risk

Large bodies of water moderate cliamate

Improved ecological balance

Consequences of dams

Physical effects

• evaporation losses

• Increased groundwater seepage

• Decreased volume of water downstream

• Increased severity of earthquakes

• Growth of weeds + eutrophication

• Decreased flow → death of riverbank and floodplain vegetation

• Deposition within lakes

• Erosion of delta (bc less sediment and higher velocity)

• Decreased fish stocks

• Lack of sediment movement downstream

• Less flood so can’t use as natural fertilizer

• Less nutrients downstream → deterioration of aquatic life

Socioeconomic problems

• flooding of historical sites

• Displacement of population

• Less fertile farmland that relied on floods

• Waterborne disease

CASE STUDY: The Three Gorges Dam, Yangtze River Basin, China

Annual floods in basin from snow melt → loss of lives and grain crops

Built dam to

1. Control annual flooding

2. Generate hydroelectricity

3. Increasing shipping capacity

Benefits:

• safer shipping

• Increased employment → migration

• Provinces near dam → wealthier

• Hydro → less GHG and air pollution

• Reservoir moderates temp

Consequences

• Many people relocated

• Cultural monuments lost

• Provinces away from dam lost funding bc cost of dam

• Vulnerable to military attack bc country dependent on single energy source

• Dam traps sediment and reservoir fills w/ it

• Increased likeliness of earthquake

• Rebuild downs

• Water carries less sediment → erosion

• Wildlife habitats drown

• Increased evap

What are Integrated Drainage Basin Management (IDBN) schemes

Aim to deliver sustainable use of world’s limited freshwater resources

Manage drainage basin as a single integrate unit, as there are many inte-related and inter-dependent factors involved

Elements to successful IDBN

Govs, industries, ppl have long-term vision agreed to by all stakeholders

Integration of policies, decisions, costs across interests

Strategic decision-making

Participation by all stake-holders

Well-informed, transparent planning

Adequate investment

Knowledge of river basins and the natural and socioeconomic forces that influence it

Global Water Partnership (GWP)

International advisory body for IDBN

5 principles

1. Multiple uses (drinking, washing, livelihood)

2. Holistic management (examine supply and demand)

3. Multiple perspectives (economic, social, environmental need)

4. Participatory approach (local communities involved)

5. Women’s involvement (role in collecting, distributing, and managing, esp in LICs)

Costs and benefits of IDBN

Keep in mind costs/benefits difficult to compare bc benefits cannot be quantified like costs

CASE STUDY: IDBM plan for the Broadlands Rivers Catchment

Background

• Broadlands River catchment supplies water to eastern Englands Broads

• Water demand from

  • Tourism (boating, fishing) brings in money and supports many jobs

  • Farming (fertile land) supports many jobs and occupies most of the land

Processes

• Desire to expand agriculture for increasing + remove mosquito breeding ground → broads drained → less peat production (fuel) + sinking

• Broads used as sewage disposal → eutrophication

• New farmland created → vegetation destroyed → eutrophication

• Boating → riverbank erosion + stir up sediment → sediment downstream

• Cattle trampling → bank collapse + siltation

2014 IDBM Plan aiming to address problems of

• Water quality (waste + pesticides)

• Habitat protection

• River flooding

• Land management for farmers

• Involving local communities

Why are wetlands drained

Wetlands referred to as useless space (smell, breeding ground for pest and disease)

Made useful by drainage

• makes agricultural space

• Oil and gas exploration

• Peat is fuel

Importance of wetlands

Filtration (peat purifies impurities)

Biologically diverse ecosystem (habitats and breeding)

Carbon source (peat)

Store floodwater

Control erosion (slows water + grows vegetation that holds sediment)

Economic value as tourist attractions

Support livelihoods (fishing, hunting)

Ramsar Convention

International treaty to halt worldwide wetland loss and conserve through wise use and management

Signed in 1971 after concerns about world-wide wetland threats

Countries meet every 3yrs to make politics and monitor wetlands

Operates under 3 pillars

1. Work for wise use of all wetlands

2. Designate wetlands for List of Wetlands of International Importance

3. Cooperate internationally on transboundary wetlands

CASE STUDY: future possibilities of the Florida Everglades

Background

• internationally significant wetland on Ramsar List

• Fragile ecosystem disturbed by competing demands by humans

Water demand

• Warm climate and fertile soil → cleared for farming

• Annual flooding → drainage canals built to carry water to ocean + Herbert Hoover Dyke dam built

• Population growth → water use

• Holiday visitors → water use

Impacts of human water use

• Groundwater wells → saltwater intrusion

• Roads and buildings → water can’t replenish groundwater + drillers must dig further → more room for saltwater

• Canals → less flow → ground dry out → fires + soil oxidizes → decreased soil levels → expose roots, pipes, power cables

• Farmers upstream release fertilizers + pesticides → mercury

Management

• established as national park

  • Positives: visitors can see w/o damaging as much, more ppl who understand environment

  • Negatives: more visitors cause damages

• Conservation measures (releasing water, removing invasive plants)

• Community responsibility to protect

• Tourism to brin in finances and educate visitors

CASE STUDY: Flood mitigation Indus River