Subchapter 3 in the first chapter of Hydrology and Fluvial Geomorphology, suitable for AS students, consisting in the following: river processes, velocity, flows and Hjulstrom Curve.
CAMBRIDGE GEOGRAPHY AS - HYDROLOGY AND FLUVIAL GEOMORPHOLOGY; 1.1. DRAINAGE B...George Dumitrache
Introductory presentation of the drainage basin systems in the first chapter of Hydrology and Fluvial Geomorphology, suitable for AS students, consisting in the following: the global hydrological cycle, store, flows, the drainage systems, precipitation, evapotranspiration, interception, infiltration, percolation, drainage patterns, the water balance.
Geography notes Hydrology, Atmosphere, Weathering, Population and Migration
Casestudies aren't included - sorry. Hope these are helpful. Good luck everyone with your exams.
CAMBRIDGE GEOGRAPHY A2 REVISION - PRODUCTION, LOCATION AND CHANGE: 11.1 AGRICULTURAL SYSTEMS AND FOOD PRODUCTION. It contains: ley terms and definitions, topic summary, additional work and suggested websites.
CAMBRIDGE AS GEOGRAPHY REVISION: HYDROLOGY AND FLUVIAL GEOMORPHOLOGY - 1.2 RA...George Dumitrache
A presentation of the second subchapter (Rainfall Discharge Relationships) from the first chapter (Fluvial Geomorphology) of Revision for Geography AS Cambridge exams.
Hydrology and Fluvial Geo morphology for CAMBRIDGE AS level Yonas Gemeda
This power point lesson describes about the hydrology and rivers work in detail with different tools, which is more important for students and candidates of Cambridge Examination at AS level.
CAMBRIDGE GEOGRAPHY AS - HYDROLOGY AND FLUVIAL GEOMORPHOLOGY; 1.1. DRAINAGE B...George Dumitrache
Introductory presentation of the drainage basin systems in the first chapter of Hydrology and Fluvial Geomorphology, suitable for AS students, consisting in the following: the global hydrological cycle, store, flows, the drainage systems, precipitation, evapotranspiration, interception, infiltration, percolation, drainage patterns, the water balance.
Geography notes Hydrology, Atmosphere, Weathering, Population and Migration
Casestudies aren't included - sorry. Hope these are helpful. Good luck everyone with your exams.
CAMBRIDGE GEOGRAPHY A2 REVISION - PRODUCTION, LOCATION AND CHANGE: 11.1 AGRICULTURAL SYSTEMS AND FOOD PRODUCTION. It contains: ley terms and definitions, topic summary, additional work and suggested websites.
CAMBRIDGE AS GEOGRAPHY REVISION: HYDROLOGY AND FLUVIAL GEOMORPHOLOGY - 1.2 RA...George Dumitrache
A presentation of the second subchapter (Rainfall Discharge Relationships) from the first chapter (Fluvial Geomorphology) of Revision for Geography AS Cambridge exams.
Hydrology and Fluvial Geo morphology for CAMBRIDGE AS level Yonas Gemeda
This power point lesson describes about the hydrology and rivers work in detail with different tools, which is more important for students and candidates of Cambridge Examination at AS level.
CAMBRIDGE AS GEOGRAPHY REVISION: HYDROLOGY AND FLUVIAL GEOMORPHOLOGY - 1.1 DR...George Dumitrache
A presentation of the first subchapter (Drainage Basin Systems) from the first chapter (Hydrology and Fluvial Geomorphology) of Revision for Geography AS Cambridge exam.
A2 Geography Revision for Coastal Environments, subchapter 8.2 Coastal Landforms of Cliffed and Constructive Coasts. It is suitable for Year 13 Geography, Cambridge Examination in November 2016. It contains: key terms and definitions, a topic summary, sketches and descriptions, additional work (6 questions for testing your knowledge) and some suggested websites.
CAMBRIDGE GEOGRAPHY A2 REVISION - ENVIRONMENTAL MANAGEMENT: ENVIRONMENTAL DEGRADATION. Presentation suitable for Cambridge A2 students. It contains: key words and definitions, topic summary, additional work and suggested websites.
CAMBRIDGE AS GEOGRAPHY REVISION: ATMOSPHERE AND WEATHER - 2.3 WEATHER PROCESS...George Dumitrache
A comprehensive presentation of subchapter 2.3 Weather Processes and Phenomena, from the second chapter of Physical Geography, AS Cambridge, Atmosphere and Weather.
AS Level Human Geography - Urbanization and SettlementArm Punyathorn
In this chapter, we will discuss how our cities/ villages are shaped. We will look at how residential factors can affect incomes and poverty, migration and population.
A2 Geography Revision for Coastal Environments, subchapter 8.1 Waves Marine and Subaerial Processes. It is suitable for Year 13 Geography, Cambridge Examination in November 2016. It contains: key terms and definitions, a topic summary, sketches and descriptions, additional work (6 questions for testing your knowledge) and some suggested websites.
CAMBRIDGE GEOGRAPHY A2 REVISION - SUSTAINABLE MANAGEMENT OF HAZARDOUS ENVIRONMENTS. Presentation suitable for Cambridge A2 students. It contains: key terms and definitions, topic summary, additional work and suggested websites.
AS Level Physical Geography - Hydrology and Fluvial GeomorphologyArm Punyathorn
Water is an agent of change in the atmosphere, geosphere and biosphere. In this chapter we will try to understand the passage of water as it changes states.We will also look at how the forces of river can shape land forms as well as civilization
CAMBRIDGE GEOGRAPHY A2 REVISION - ENVIRONMENTAL MANAGEMENT: SUSTAINABLE ENERGY SUPPLIES. Presentation suitable for Cambridge A2 level students. It contains: key terms and definitions, topic summary, additional works and suggested websites.
CAMBRIDGE AS GEOGRAPHY REVISION: HYDROLOGY AND FLUVIAL GEOMORPHOLOGY - 1.3 RI...George Dumitrache
A presentation of the third subchapter (River Channel Processes) from the first chapter (Hydrology and Fluvial Geomorphology) of Revision for Geography AS Cambridge exam.
CAMBRIDGE AS GEOGRAPHY REVISION: HYDROLOGY AND FLUVIAL GEOMORPHOLOGY - 1.4 HU...George Dumitrache
A presentation of the fourth subchapter (The Human Impact) from the first chapter (Hydrology and Fluvial Geomorphology) of Revision for Geography AS Cambridge exam.
CAMBRIDGE AS GEOGRAPHY REVISION: HYDROLOGY AND FLUVIAL GEOMORPHOLOGY - 1.1 DR...George Dumitrache
A presentation of the first subchapter (Drainage Basin Systems) from the first chapter (Hydrology and Fluvial Geomorphology) of Revision for Geography AS Cambridge exam.
A2 Geography Revision for Coastal Environments, subchapter 8.2 Coastal Landforms of Cliffed and Constructive Coasts. It is suitable for Year 13 Geography, Cambridge Examination in November 2016. It contains: key terms and definitions, a topic summary, sketches and descriptions, additional work (6 questions for testing your knowledge) and some suggested websites.
CAMBRIDGE GEOGRAPHY A2 REVISION - ENVIRONMENTAL MANAGEMENT: ENVIRONMENTAL DEGRADATION. Presentation suitable for Cambridge A2 students. It contains: key words and definitions, topic summary, additional work and suggested websites.
CAMBRIDGE AS GEOGRAPHY REVISION: ATMOSPHERE AND WEATHER - 2.3 WEATHER PROCESS...George Dumitrache
A comprehensive presentation of subchapter 2.3 Weather Processes and Phenomena, from the second chapter of Physical Geography, AS Cambridge, Atmosphere and Weather.
AS Level Human Geography - Urbanization and SettlementArm Punyathorn
In this chapter, we will discuss how our cities/ villages are shaped. We will look at how residential factors can affect incomes and poverty, migration and population.
A2 Geography Revision for Coastal Environments, subchapter 8.1 Waves Marine and Subaerial Processes. It is suitable for Year 13 Geography, Cambridge Examination in November 2016. It contains: key terms and definitions, a topic summary, sketches and descriptions, additional work (6 questions for testing your knowledge) and some suggested websites.
CAMBRIDGE GEOGRAPHY A2 REVISION - SUSTAINABLE MANAGEMENT OF HAZARDOUS ENVIRONMENTS. Presentation suitable for Cambridge A2 students. It contains: key terms and definitions, topic summary, additional work and suggested websites.
AS Level Physical Geography - Hydrology and Fluvial GeomorphologyArm Punyathorn
Water is an agent of change in the atmosphere, geosphere and biosphere. In this chapter we will try to understand the passage of water as it changes states.We will also look at how the forces of river can shape land forms as well as civilization
CAMBRIDGE GEOGRAPHY A2 REVISION - ENVIRONMENTAL MANAGEMENT: SUSTAINABLE ENERGY SUPPLIES. Presentation suitable for Cambridge A2 level students. It contains: key terms and definitions, topic summary, additional works and suggested websites.
CAMBRIDGE AS GEOGRAPHY REVISION: HYDROLOGY AND FLUVIAL GEOMORPHOLOGY - 1.3 RI...George Dumitrache
A presentation of the third subchapter (River Channel Processes) from the first chapter (Hydrology and Fluvial Geomorphology) of Revision for Geography AS Cambridge exam.
CAMBRIDGE AS GEOGRAPHY REVISION: HYDROLOGY AND FLUVIAL GEOMORPHOLOGY - 1.4 HU...George Dumitrache
A presentation of the fourth subchapter (The Human Impact) from the first chapter (Hydrology and Fluvial Geomorphology) of Revision for Geography AS Cambridge exam.
This is an introduction to our Hydrology unit at International School Manila. It looks at how much water there is on our planet and tries to explain the astronomical figures in terms that the students (and teachers for that matter) understand.
AS Level Physical Geography - Rocks and WeatheringArm Punyathorn
The earth's surface is an ever-changing entity. With the forces of weather and climate and tectonic variability, the rocks and minerals that make up the earth are always changing in size, shape and forms - a fascinating, ancient, never-ending process.
This presentation will help students to know about the basic concept and understanding about the rivers that What is river? What is the flow of river? What are the types of river or its drainage pattern? Rivers Erosional and Depositional Landforms.
River is a most Important agent in geological field and most important roll of the physical, Chemical and biological erosion. It is common factors of river.
07. DEPTH STUDY GERMANY: NAZI REGIME - REICHSTAG FIRE SOURCESGeorge Dumitrache
07. DEPTH STUDY GERMANY: NAZI REGIME - REICHSTAG FIRE
On February 27, 1933, the German parliament (Reichstag) building burned down. The Nazi leadership and its coalition partners used the fire to claim that Communists were planning a violent uprising. They claimed that emergency legislation was needed to prevent this. The resulting act, commonly known as the Reichstag Fire Decree, abolished a number of constitutional protections and paved the way for Nazi dictatorship.
05. DEPTH STUDY GERMANY: NAZI REGIME - HITLER CONSOLIDATING POWER 1933-34.PPTXGeorge Dumitrache
05. DEPTH STUDY GERMANY: NAZI REGIME - HITLER CONSOLIDATING POWER 1933-34.PPTX
Following Hitler’s appointment as chancellor the Nazis were finally in a position of power.
However, this power was limited, as the Nazis were just one party in a three party coalition government, under President Hindenburg.
This topic will explore how the Nazis managed to eliminate their opposition and consolidate ultimate power over Germany, whilst maintaining an illusion of democracy.
It will first explore this topic in chronological order, from the Reichstag Fire through to the death of President Hindenburg, and then explore it thematically in the last section. On the 31 January 1933, Hitler, conscious of his lack of a majority in the Reichstag, immediately called for new elections to try and strengthen his position. The Nazis aimed to increase their share of the vote so that they would have a majority in the Reichstag. This would allow them to rule unopposed and unhindered by coalition governments.
Over the next two months, they launched themselves into an intense election campaign.
On 27 February 1933, as the campaign moved into its final, frantic days, the Reichstag, the German Parliament building, was set on fire and burnt down. An atmosphere of panic and terror followed the event.
This continued when a young Dutch communist, Van der Lubbe was arrested for the crime.
The Nazi Party used the atmosphere of panic to their advantage, encouraging anti-communism. Göring declared that the communists had planned a national uprising to overthrow the Weimar Republic. This hysteria helped to turn the public against the communists, one of the Nazis main opponents, and 4000 people were imprisoned.
The day after the fire, Hindenburg signed the Emergency Decree for the Protection of the German People. On the 28 February 1933, President Hindenburg signed the Emergency Decree for the Protection of the German People. This decree suspended the democratic aspects of the Weimar Republic and declared a state of emergency.
This decree gave the Nazis a legal basis for the persecution and oppression of any opponents, who were be framed as traitors to the republic. People could be imprisoned for any or no reason.
The decree also removed basic personal freedoms, such as the freedom of speech, the right to own property, and the right to trial before imprisonment.
Through these aspects the Nazis suppressed any opposition to their power, and were able to start the road from democracy to a dictatorship. The atmosphere of uncertainty following the Reichstag Fire secured many voters for the Nazi party.
The SA also ran a violent campaign of terror against any and all opponents of the Nazi regime. Many were terrified of voting of at all, and many turned to voting for the Nazi Party out of fear for their own safety. The elections were neither free or fair.
On the 5 March 1933, the elections took place, with an extremely high turnout of 89%.
The Nazis secured 43.9% of the vote.
DEPTH STUDY GERMANY: NAZI REGIME - 04. HITLER BECOMING CHANCELLOR 1933George Dumitrache
Hitler was not immediately appointed chancellor after the success of the July 1932 elections, despite being leader of the largest party in the Reichstag. It took the economic and political instability (with two more chancellors failing to stabilise the situation) to worsen, and the support of the conservative elite, to convince Hindenburg to appoint Hitler.
Hitler was sworn in as the chancellor of Germany on the 30 January 1933. The Nazis were now in power.
DEPTH STUDY GERMANY: WEIMAR REPUBLIC - 08. NAZIS IN THE WILDERNESSGeorge Dumitrache
The “Lean Years” (also called the "wilderness" years) of Hitler and the Nazi Party in Germany refer to the period between 1924 and 1928 when the Nazi party did not have high levels of support and still suffered from humiliation over the Munich Putsch. Why where these years “lean”?
DEPTH STUDY GERMANY: WEIMAR REPUBLIC - 07. STRESEMMAN ERA 1924-1929George Dumitrache
The period 1924-1929 was a time when the Weimar economy recovered and cultural life in Germany flourished. This dramatic turnabout happened in large part because of the role played by Gustav Stresemann who became Chancellor in August 1923 during the hyperinflation crisis.
DEPTH STUDY GERMANY: WEIMAR REPUBLIC - 06. THE BEER HALL PUTSCH 1923George Dumitrache
The Beer Hall Putsch, also known as the Munich Putsch, was a failed coup d'état by Nazi Party (Nationalsozialistische Deutsche Arbeiterpartei or NSDAP) leader Adolf Hitler, Generalquartiermeister Erich Ludendorff and other Kampfbund leaders in Munich, Bavaria, on 8–9 November 1923, during the Weimar Republic. Approximately two thousand Nazis marched on the Feldherrnhalle, in the city centre, but were confronted by a police cordon, which resulted in the deaths of 16 Nazi Party members and four police officers. Hitler escaped immediate arrest and was spirited off to safety in the countryside. After two days, he was arrested and charged with treason. The putsch brought Hitler to the attention of the German nation for the first time and generated front-page headlines in newspapers around the world. His arrest was followed by a 24-day trial, which was widely publicised and gave him a platform to express his nationalist sentiments to the nation. Hitler was found guilty of treason and sentenced to five years in Landsberg Prison, where he dictated Mein Kampf to fellow prisoners Emil Maurice and Rudolf Hess. On 20 December 1924, having served only nine months, Hitler was released. Once released, Hitler redirected his focus towards obtaining power through legal means rather than by revolution or force, and accordingly changed his tactics, further developing Nazi propaganda.
DEPTH STUDY GERMANY: WEIMAR REPUBLIC - 05. HYPERINFLATIONGeorge Dumitrache
Hyperinflation affected the German Papiermark, the currency of the Weimar Republic, between 1921 and 1923, primarily in 1923. It caused considerable internal political instability in the country, the occupation of the Ruhr by France and Belgium, and misery for the general populace.
DEPTH STUDY GERMANY: WEIMAR REPUBLIC - 03. THE TREATY OF VERSAILLES IMPACT ON...George Dumitrache
Thanks to the Treaty of Versailles, Germany's ability to produce revenue-generating coal and iron ore decreased. As war debts and reparations drained its coffers, the German government was unable to pay its debts. Some of the former World War I Allies didn't buy Germany's claim that it couldn't afford to pay.
DEPTH STUDY GERMANY: WEIMAR REPUBLIC - 02. THE NOVEMBER REVOLUTION 1918George Dumitrache
The German Revolution or November Revolution was a civil conflict in the German Empire at the end of the First World War that resulted in the replacement of the German federal constitutional monarchy with a democratic parliamentary republic that later became known as the Weimar Republic. The revolutionary period lasted from November 1918 until the adoption of the Weimar Constitution in August 1919. Among the factors leading to the revolution were the extreme burdens suffered by the German population during the four years of war, the economic and psychological impacts of the German Empire's defeat by the Allies, and growing social tensions between the general population and the aristocratic and bourgeois elite.
DEPTH STUDY GERMANY: WEIMAR REPUBLIC - 01. THE EFFECT OF WW1 ON GERMANYGeorge Dumitrache
DEPTH STUDY GERMANY: WEIMAR REPUBLIC - 01. THE EFFECT OF WW1 ON GERMANY. This presentation covers the social, economic and political impact of war along with a brief analysis of the physical cost of war.
QUESTIONS AND ANSWERS - LEAGUE OF NATIONS. The League of Nations was an international organization, headquartered in Geneva, Switzerland, created after the First World War to provide a forum for resolving international disputes.
ABYSSINIAN CRISIS. The Abyssinian Crisis was over in 1936. Italy and Mussolini continually ignored the League of Nations and fully annexed Abyssinia on May 9th 1936. The League of Nations was shown to be ineffective. The League had not stood up against one of the strongest members and fulfilled the promise of collective security.
Manchurian Crisis. On September 18, 1931, an explosion destroyed a section of railway track near the city of Mukden. The Japanese, who owned the railway, blamed Chinese nationalists for the incident and used the opportunity to retaliate and invade Manchuria.
05. LEAGUE OF NATIONS - Great Depression and LON.pptxGeorge Dumitrache
GREAT DEPRESSION AND THE LEAGUE OF NATIONS. The Great Depression of 1930-33 meant people turned to extremist dictators such as Hitler and Mussolini, who were keen to invade other countries. This made it hard for the League to maintain peace. The League had some very ambitious plans and ideals – to stop war and make the world a better place.
Palestine last event orientationfvgnh .pptxRaedMohamed3
An EFL lesson about the current events in Palestine. It is intended to be for intermediate students who wish to increase their listening skills through a short lesson in power point.
2024.06.01 Introducing a competency framework for languag learning materials ...Sandy Millin
http://sandymillin.wordpress.com/iateflwebinar2024
Published classroom materials form the basis of syllabuses, drive teacher professional development, and have a potentially huge influence on learners, teachers and education systems. All teachers also create their own materials, whether a few sentences on a blackboard, a highly-structured fully-realised online course, or anything in between. Despite this, the knowledge and skills needed to create effective language learning materials are rarely part of teacher training, and are mostly learnt by trial and error.
Knowledge and skills frameworks, generally called competency frameworks, for ELT teachers, trainers and managers have existed for a few years now. However, until I created one for my MA dissertation, there wasn’t one drawing together what we need to know and do to be able to effectively produce language learning materials.
This webinar will introduce you to my framework, highlighting the key competencies I identified from my research. It will also show how anybody involved in language teaching (any language, not just English!), teacher training, managing schools or developing language learning materials can benefit from using the framework.
Instructions for Submissions thorugh G- Classroom.pptxJheel Barad
This presentation provides a briefing on how to upload submissions and documents in Google Classroom. It was prepared as part of an orientation for new Sainik School in-service teacher trainees. As a training officer, my goal is to ensure that you are comfortable and proficient with this essential tool for managing assignments and fostering student engagement.
We all have good and bad thoughts from time to time and situation to situation. We are bombarded daily with spiraling thoughts(both negative and positive) creating all-consuming feel , making us difficult to manage with associated suffering. Good thoughts are like our Mob Signal (Positive thought) amidst noise(negative thought) in the atmosphere. Negative thoughts like noise outweigh positive thoughts. These thoughts often create unwanted confusion, trouble, stress and frustration in our mind as well as chaos in our physical world. Negative thoughts are also known as “distorted thinking”.
Welcome to TechSoup New Member Orientation and Q&A (May 2024).pdfTechSoup
In this webinar you will learn how your organization can access TechSoup's wide variety of product discount and donation programs. From hardware to software, we'll give you a tour of the tools available to help your nonprofit with productivity, collaboration, financial management, donor tracking, security, and more.
Students, digital devices and success - Andreas Schleicher - 27 May 2024..pptxEduSkills OECD
Andreas Schleicher presents at the OECD webinar ‘Digital devices in schools: detrimental distraction or secret to success?’ on 27 May 2024. The presentation was based on findings from PISA 2022 results and the webinar helped launch the PISA in Focus ‘Managing screen time: How to protect and equip students against distraction’ https://www.oecd-ilibrary.org/education/managing-screen-time_7c225af4-en and the OECD Education Policy Perspective ‘Students, digital devices and success’ can be found here - https://oe.cd/il/5yV
How to Split Bills in the Odoo 17 POS ModuleCeline George
Bills have a main role in point of sale procedure. It will help to track sales, handling payments and giving receipts to customers. Bill splitting also has an important role in POS. For example, If some friends come together for dinner and if they want to divide the bill then it is possible by POS bill splitting. This slide will show how to split bills in odoo 17 POS.
Model Attribute Check Company Auto PropertyCeline George
In Odoo, the multi-company feature allows you to manage multiple companies within a single Odoo database instance. Each company can have its own configurations while still sharing common resources such as products, customers, and suppliers.
How to Make a Field invisible in Odoo 17Celine George
It is possible to hide or invisible some fields in odoo. Commonly using “invisible” attribute in the field definition to invisible the fields. This slide will show how to make a field invisible in odoo 17.
The French Revolution, which began in 1789, was a period of radical social and political upheaval in France. It marked the decline of absolute monarchies, the rise of secular and democratic republics, and the eventual rise of Napoleon Bonaparte. This revolutionary period is crucial in understanding the transition from feudalism to modernity in Europe.
For more information, visit-www.vavaclasses.com
5. Occurs when
rivers erode
or wear
away the
land surface
over which
they are
flowing
The rock
particles
which are
worn away
from the land
surface are
called
sediments
7. DEPOSITION
Happens when the sediment
may settle either on the river
bed.
Where the water flows more
slowly as in the flood plain, or
eventually on the sea bed.
8. HYDRAULIC ACTION
A process by which the force of the
flowing water may remove particles
from the banks or bed
9. CAVITATION
A form of hydraulic action caused
by bubbles of air collapsing.
The resultant shock waves hit and
slowly weaken the banks.
This is the slowest and least
effective erosion in process.
10.
11.
12.
13.
14.
15. ATTRITION
A process by which as rocks are carried along by a
river, they knock against each other so pieces break
off and the rock fragments are reduced in size and
become rounded.
16. CORRASION
A process by which the rock particles which are then
carried by the river may be used as tools to help
break more rock fragments from the river bed and
banks.
Example: Circular holes called pot holes may be cut in
a rocky river bed.
19. A process by which rivers can dissolve some
rocks such as limestone.
Example
At Mulu in Sarawak, rivers have dissolved the
limestone and created huge caverns (large
caves) through which they flow underground.
20. Rivers flow in channels and the sides of the channel are called
banks, with the floor of the channel known as the river bed.
Rivers can erode river channels in four main ways such as:
HYDRAULIC ACTION
A process by which the force
of the flowing water may
remove particles from the
banks or bed
CORRASION
A process by which the rock
particles which are then
carried by the river may be
used as tools to help break
more rock fragments from
the river bed and banksATTRITION
A process by which as rocks
are carried along by a river,
they knock against each
other so pieces break off
and the rock fragments are
reduced in size and become
rounded
SOLUTION
A process by which rivers can
dissolve some rocks such as
limestone
C
A
S
H
21. TRANSPORTATION
Is a process where the sediment
produced by erosion is carried
away downstream by the river
• 3 main processes:
• Bedload
• Suspended Load
• Dissolved/Solution Load
22. BEDLOAD
Larger particles which cannot be
picked up by current may be
moved along the bed of the river
in two ways:
- Traction
- Saltation
23. TRACTIO
N
When the large particles roll or slide
along the river bed. Large rocks are
only moved after heavy rain when the
river has a large volume of water and
is fast flowing.
24. SALTATION
When particles are temporarily lifted
up by the current and bounced along
the bed in a hopping motion.
25. SUSPENDED
LOAD0
Then small particles such as sand and
clay are carried along without touching
the river bed. These small particles are
just floating, and lightest particles are
near to the surface of the water.
27. RIVER TRANSPORT
SUSPENSION
when small particles such as
sand and clay are carried along
without touching the river bed,
small particles are just floating,
and lightest particles are near
to the surface of the water
SOLUTION
when rainwater can slowly
dissolve limestone rock.
SALTATION
when particles are lifted
up by the current and
bounced along the bed
in a hopping motion
TRACTION
when the largest particles
roll or slide along the river
bed, moved after heavy rain
when the river has a large
volume of water and is fast
flowing
29. RIVER DEPOSITION
The speed of flow of a river is reduced the river may no
longer have enough energy to transport its load of
sediment.
The larger particles will sink and settle first while the
finer particles will be carried further before settling, or
they may be carried all the way to the sea. This sinking
and settling of the river’s sediment is called river
deposition.
Deposition may occur on the river bed, or on the inside
curve of a river bend, or on the river banks
The sediment which is deposited in the sea at the river
mouth may build up new land known as delta.
30. RIVER
DEPOSITION
Decrease in velocity less energy and no longer had
competence and capacity to carry all its load. Therefore,
largest/heaviest particles, materials begins to be
deposited.
Occurs when:
Low discharge following a period of low precipitation
Less velocity when river enter sea or lake
Shallower water occurs on inside of a meander
The load suddenly increase (debris from landslide)
River overflow its bank so velocity outside channel is
reduced (resulting in floodplain)
32. VELOCITY
Velocity is the speed of a river (m/s). Can influence
the turbulence:
High Velocity:
The amount of energy still available after friction
will be greater and so turbulence increases.
The faster the flow of river the larger the quantity
and size of particles (load) which can be
transported.
Low Velocity:
Less energy to overcome the friction.
Turbulence decreases and may not be visible to
human eye.
Sediment will remains undisturbed.
Reduction in turbulence may lead to deposition of
sediment.
33.
34.
35. Velocity of a river is influenced by
three factors:
(1) Channel shape in cross-section.
(2) Roughness of the channel’s bed
and banks.
(3) Channel slope.
36. 1. CHANNEL SHAPE IN CROSS
SECTION
Simply describe by the term ‘Hydraulic
Radius’ (cross section area/wetted
perimeter).
Wetted perimeter - shape of the channel
or its cross section affects the extent to
which water is in contact with its channel.
The greater the wetted perimeter, the
greater the friction between the water
and the banks and the bed of the channel,
and the slower the flow of river.
37.
38. River volume: 6 sq m (2m x 3m)
Wetted perimeter: 7 metres (2m + 3m + 2m).
The 7 metres will be represent the friction
slowing the river down.
39. Volume: 24 sq metres
Wetted perimeter: 14
metres.
Shape of the river
a major influence.
A river with the same
volume of water as Ex 2 but
with a different shape will
have a different friction
Volume: 24 sq metres
Wetted perimeter is 26
metres almost double that
of Example 2 which means
that the river will be slower
as a larger part of the river
energy is used to overcome
friction. The gradient of the
river channel is only one
factor to influence the
speed of the river.
40. Example
Stream A: larger hydraulic radius
Small amount of water in contact with the wetted
perimeter.
Creates less friction reduce energy loss
allows greater velocity
Stream B: smaller hydraulic radius
Large amount of water in contact with the wetted
perimeter.
Creates greater friction more energy loss
reduce velocity
41. 2. ROUGHNESS OF THE CHANNEL’S BED AND
BANKS
Material such as rocks
in the channel can
influence the speed.
Whether rocks on the
river bed are smooth
or rough or uneven.
Rocks that protrude
out from the bank can
slow the pace of the
water as friction slows
it down as it passes
the obstacles.
42. In figure A, the channel
is smooth while that in
figure B is rough or
uneven with boulders on
the river bed as well as
rocks that protrude out
from the bank.
A river that flows
through such a river has
to overcome such
obstacles and therefore
there will be more
friction and the velocity
of the river is reduced.
Figure A
Figure B
43. Velocity of a mountain stream is less than that
of a lowland. Mountain stream is likely to pick up
loose material and carry it downstream
Example:
Mountainous / Upper course of a river
Despite high velocity in waterfalls, the large
number of angular rocks, coarse-grained
banks and protrusions increase frictions and
reduce overall velocity
Lower course of a river:
As there is little resistance from the smooth
bed and banks, there is little friction and river
flows faster
44. 3. CHANNEL SLOPE
A river flowing down a steep slope or gradient
has higher velocity than one which flows
down a gentler gradient.
For example, the speed of flow in a river that
plunges down a steep slope in the form of a
waterfall is much higher than the speed of
flow in a river that winds down a gentler slope.
45. CHANNEL SLOPE
Changes in gradient are related to
changes in discharge.
Discharge is higher in the lower
course.
Since gradient decreases as discharge
increases, river can transport the same
quantity and size of sediment load in
the gentler lower course as it can in
the steeper upper course.
47. PATTERNS OF FLOW
River water has a certain amount of available energy.
Greatest when there is a large amt of water and when
there is steep gradient.
Most of the river’s energy used up in overcoming friction
with the bed and banks.
Friction high in the upper reaches of a river where
large boulders may protrude into large river’s flow.
There are three patterns
of flow:
1. Laminar flow
2. Turbulent flow
3. Helicoidal flow
48. LAMINAR FLOW
Horizontal movement of water. Travel
over the sediment in the river bed
without disturbing it. Rare in reality but
common in the lower reaches.
Condition:
Smooth
Straight channel
Shallow water
Non-uniform velocity
49. TURBULENT FLOW
Series of erratic (inconsistent) eddies. Both
vertical & horizontal in downstream
direction. Depends on the amount of
energy available after friction has been
overcome.
Conditions:
Complex channel shape eg. Winding
channels, riffles and pools
Cavitation as eddies trap air in pores,
cracks crevices which is then release
52. HELICOIDAL FLOW
Usually occur in meanders.
A corkscrew movement in a meander.
It is responsible for moving material
from the outside of one meander bend
and depositing on the inside of the next
bend.
56. HJULSTROM CURVE
A graph used by hydrologists
to determine whether a river
will erode, transport or deposit
sediment.
The graph takes sediment size
and channel velocity into
account.
The curve shows several key
ideas about the relationships
between erosion,
transportation and deposition.
57. HJULSTROM
CURVE
Shows that particles of a size
around 1mm require the least
energy to erode, as they are
sands that do not coagulate.
Particles smaller than these fine
sands are often clays require
a higher velocity to produce the
energy required to split the
small clay particles which have
coagulated.
58. Larger particles
pebbles are eroded at
higher velocities
Very large objects
boulders require the
highest velocities to
erode.
When the velocity drops
below this velocity called the
line of critical velocity,
particles will be deposited or
transported, instead of
being eroded, depending on
the river's energy.
59.
60.
61. THE LANGUAGE OF HJULSTROM
CURVE
Critical erosion velocity: The lowest velocity at which
grains of a certain size can be moved.
Critical deposition velocity: The velocity at which
particles of particular sizes are laid down
Entrainment: Materials being picked up by river
Flocculate: Materials stick together in the river
Clay particles: Tiny particles between 0.001 and
0.01mm in size
Sand particles: Sediments between 0.1 and 2mm in
size
Cobbles: Sediments between 20 and 300mm in size
62. HJULSTROM CURVE
Key:
Silt/sand are picked up (entrained) at the
lowest velocities.
Clays are difficult to pick up as pebbles –
although they are small particles, they are
very cohesive and the claybed is very
smooth.
Large boulders are dropped easily.
Clay particles can be transported in
suspension at very low velocities.
64. HJULSTROM CURVE
1. Name the type of sediment that requires the
lowest velocity to be eroded. [1]
2. Name the type of sediment that is likely to
be transported at all velocities. [1]
3. Describe and explain the relationship
between
water velocity and the erosion of clay
and sand particles. [4]
4. Explain the variation in water velocity that is
required to transport and to deposit
sediments of different particle diameter. [4]
65. ANSWER
1. Sand
2. Clay
3. Clay - requires higher energy to be eroded
- tend to stick together
- are difficult to pick up as pebbles
- although they are small particles, they are very
cohesive
Sand - requires lower energy
- sand particles are unconsolidated (loose)
4. Boulders - require large velocities to be transported
Small particles - Clay & silt – can be held in suspension
area at low velocity.
Energy velocity to transport is always lower than
energy