Tropical Monsoon Forests

Tropical Monsoon Forests

• They are found in the tropics
• The place has high temperature [about 26° C] and rainfall[1500 mm per year]
• These place also have distinct wet and dry season/
• Example, South Asia, Southeast Asia, Southern China and Northern Australia.
• Mainly between 10°  and 25°  N and S of the equator
• Wet and dry season are caused by the monsoon winds.

Structure of Forest

• This forest has only 3 layers.
• Canopy,Understory ad Undergrowth.

CANOPY
- Trees here grow to 25 to 30m
- They are more spread out compared to Tropical Rainforest
- Epiphytes,creepers,vines and parastitic plants are found within this layer

UNDERSTORY
- Tress grow up to about 15m

UNDERGROWTH
- Thick bushes and bamboos cover the forest floor.

Diversity And Density

• There are few types of tress compared to Tropical Rainforest
• It is less dense compare to tropical rainforest
• Crown of trees do not interlock
• and thus the undergrowth is able to grow,

Leaves

• Are Deciduous.
• Meaning their leaves are shed during dry season
• this to minimise water lost.
• Leaves also have waxy surface to prevent growth of bateria during wet seasons.
• Other plants such as bamboo plant minimise water lose by having narrow leaves.

Flower and fruits

• Most of the tress bare fruits in the dry seasons

Barks and Branches

• Thick and coarse
• This protect the tree from the heat of dry season
• As dry seasons are really dry, forest fire happen and the barks can protect it from the fire.
• Branches are located at the middle as it do not need to fight for sunlight.

Roots

• Tress here have long and deep roots
• this is to tap water source from deep underground as water supply is not constant.

Types of natural vegetation

Tropical rainforest
- Found in places that experience a tropical equatorial climate.
- 10° N and S of equator
- Experience High temperature [27°C]
- High Rainfall [1500 millimeters.]

Found in?

- Amazon Basin of South America
- Congo Basin of Africa
- South-east Asia




Emergent layer- 30m to 50m
-Crown appears above canopy layer
-Have thick, straight, tall trunks

Canopy Layer- 15m to 30m
- Wide, shallow and umbrella shaped crowns
- Continuous leaf cover
- Prevent sunlight form penetrating into the lower layers of the forest

Understory Layer - [6m to 15m]
- Oval-shaped crowns.
- Grow in gaps which allow sunlight to got through
- Trees usually grow into the canopy layer or emergent layer after many years

Shrub Layer [5m to 6m]
- Tree saplings and woody are found here.
- May grow up to 6m

Undergrowth Layer [0m to 5m]
- Made up of grass, mosses, fungi.
- Not much growth due to lack of sunlight

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Special Plants found:

Epiphytes:
e.g bird's nest fern , orchids.
Grow on other plants for support.

Lianas:
Thick woody vines that wind around trees to get sunlight

Parasitic Plant:
kill hosting tree to get nutrients and sunlight
e.g. strangling fig

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Characteristic Of the forest

Diversity of plant species:
- Largest diversity of plants
- more than 750 species of tree
- More than 1500 species of plants
- eg Keruing, kapur,chengal and meranti
Density
- extremely dense
- Plants grow very closely with one another
- Due to high rainfall and temperature

Leaves



- Are evergreen
- Are large and board
∟Maximize the surface area for photosynthesis
-Have waxy surface and drip tips.
∟allow water to drip off.
∟prevent harmful bacteria from growing on the leaf

Flowers And fruit

ignore my ugly drawing and spelling error...

- Are colorful and sweet smelling
- has to attract insects to do pollination

Barks and branches.
- Thin and smooth barks.
∟ No need for protection against harsh weathers
∟ Smooth so that water run of easily
∟bacteria would not grow on it
- Have branches on the top 1/3 portion of the trunk
∟To get as much sunlight as possible

Roots
-Shallow
∟do not need to reach deep
∟minerals are found on the ground
-Tall trees have buttress roots
∟ to support weight of the trees.

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Jiayou!!! :D

Coastal Protection Measures

Hard engineering


Seawalls

to protect the coast from being eroded, people have built seawalls in front of the cliff or along the coast

It is usually made out of concrete which absorb the energy of the waves and protect the coast against strong waves, especially during the storm

however, the wave energy is directed downwards, to the base of the seawall

causing it weaken and collapse

hence, seawalls have to be carefully maintain

And it is not cheap !

Breakwaters

breakwater are built off coast but parallel to it.

It is usually made of granite

it creates a zone between shallow water and the coast itself

so that water will break against it before reaching the coast

Disadvantage: it leaves other parts of the beach unprotected.

Groynes

Built right angle to the beach

it enable sediments to build up one one side.

however, the other side will be eroded.

and the long shore drift will not be able to reach it

Thus further down the beach might me eroded away

To solve it , more groynes can be build

but IT SUPER UGLY !

Gabions

Are also used to protect river banks

also used to protect other coastal protection

e.g. seawall.

however,gabions are easily destroyed by powerful waves

The wires also rust easily due to the salt in the sea water

It is also very ugly

it has a short life span of less then 15 years

However, it is the cheapest method.

Soft engineering



Stabilizing coastal dunes

Coastal dunes are great for protecting human property that is near the coast.

examples houses and roads.

natural vegetation are found in dune to make them stable

however due to human activity, dunes have became unstable

Sands Unstable dunes can blow inland and effect people's life.

to stabilize the dunes, more vegetation can be grown.

activity also needs to be minimized

Planting Mangroves along the shore

protect the coast from erosion by strong waves and harsh wind

mangrove trees have prop or kneed roots that can hold loose soils together.

studies have shown that countries that planted mangrove suffered less during the 2004 Indian Ocean Tsunami

And thus many countries are planting mangrove

however, young mangrove are very vulnerable

thus the help of the local people is needed to help take care for these your plants

Beach Nourishment

This involves adding large amounts of sand to a beach that is being eroded

When the longshore drift bring sediments down the beach,

people bring in sands from other areas to replace the sand lost

this is a very expensive method as beach quality sand is super expensive

and regular maintenance is needed

this method can only last for about 10 years

Encourage growth of coral reef

coral reefs are masses of rock-like substance growing in shallow seas

They reduces speed of the waves approaching the coast and thus protect the beach.

however due to human activities, these reef are destroy

Water pollution made it worse for them to grow as they need clear water

Some country came up with ways to encourage growth for coral reef

e.g Malaysia ban fishing the protected area

however for these methods to work, the people have to cooperate.

Coast

So sorry like SO long never post already. Have been busy with study. However, I back ! :D
For Geography, I guess you can buy guide books then helps you summaries the whole book. Here I'm using Fairfield Book Publishers' Q&A G.C.E 'o' level Elective Geography topic by topic.



It's really great ! :D I'm also using Mrs Lily Lim Notes [used to be Deyi teacher]{also known as Ben's notes} and my personal notes so if there is any mistake, I'm sorry ! :D

Coast
Definition: A coast is the part of the land which meets the sea and interacts with it. It is always changing sue to coastal processes which shapes it constantly.

Coastal erosion

Factors affecting size of wind

Wind Energy

Greater Pressure → Greater Wind speed → Greater wind energy → Larger Waves

Duration Of wind

longer time → bigger waves

Fetch [Distance]

definition:The distance over which winds blow across open water to form waves.
Longer distance→bigger waves

tides & currents as agents of erosion

Tides are daily changes in sea level due to the movement of the moon and the sun.

A coast experience high tide and low tide every 12 hours

Currents are flows of water that move either horizontally or vertically

Types of waves

Constructive waves

→ Swash is stronger then backwash
→ More materials are deposited
→ builds up the coast
→ occurs on gentle sloping coast
→ break gently with little energy

Destructive Waves

→ backwash is strong then swash
→ More materials are removed instead of deposited
→ steeply sloping coast
→ break violently with high energy

how to remember?
Backwash:backward movement of waves [move backwards take away]

Swash: Forward movement of wave [move forward deposit]

Transportation

[ignore the spelling mistake]

Wave approaches the coast at an oblique angle

The swash brings the sediments up onto the coast at an oblique angle

the backwash then carries the sediments back to the sea at a right angle

This is due to the influence of gravity

This produces a zig-zag movement along the shoreline which transport sediments from west to east producing a long shore drift

Landforms

Questions normally starts with: With a well labeled diagram, explain how (insert land form here) is formed

Please do not explain with out diagram

Diagrams are really important and they cost 6 marks or more !

there are 5 land forms. the textbook only wrote 4.

Cliff And shore platform

A cliff is formed when waves repeatedly pound against a rocky coast,

This weakens the rocks, causing line of weakness to form in the rock face

Overtime,the waves erode the coast to cut a notch along the lines of weakness

the notch may be further eroded to form a cave.

The overhanging part of the notch or cave eventually collapses with repeated pounding of the waves .

the part of the coast that is left forms a cliff.

As cliff continue to be eroded by the wave, it retreats inland

over time ,a gently sloping or falt surface called the wave-cut platform is formed

Head land and bay

the coast line consist of parallel bands of hard and soft rock which are perpendicular to the sea

the less resistant rocks gets eroded faster

while the more resistant rocks get eroded more slowly.

As less resistant rocks are constantly being eroded they curve inwards forming bays

The more resistant rocks protrude out forming headlands.

wave refraction[bending of waves] occurs as waves approaches the headland and bay

Wave energy is concentrated on headland causing erosion to occur.

While wave energy weakens and deposit sedments on the bay.

The headlands get eroded back

the bay get more deposition and form beaches

Overtime, the coastline will become a straight line again and the whole process of differential erosion will occur again.

Beaches

A beach is an area on the coast where sediments are accumulated.

These sediments are fine sand,gravel or shingle

The sediments are deposited by waves,tides or current

beaches made up of coarse material tend to be steeper.

this is due to the strong swash that deposit the on the coast

the backwash is unable yo carry them back into the sea

Beaches made up of sand and fine material tend to me gental sloping

Beaches are constantly changing its shape and size.

during stormy days beaches are eroded more quickly due to destructive waves

during clam weathers beaches are build up by constructive waves

spit and tomobolo

Long shore current deposits materials along the coastline where there is shallow and sheltered water.

Material are deposited in the direction of the long shore drift

Overtime, the accumulation of sediments will form a long narrow ridge mainly made of sand

with one end attached to main land and the other extending out to sea.

This is know as a spit

As the spit continue to extend seaward, it may join with an offshore island that is nearby

forming a tombolo

Caves,Arches,Stacks and stumps
# waves attack a crack in a headlands
# This enlarged to form a cave by the pounding of the waves compressing air in the rock face
# and by abrasion where materials carried by water is flung against the cliff
# the cave is made bigger
# if there is one on either side if headlands, an arch will result when they join
# As further erosion takes place, the arc eventually collapse
# the seaward end of the arch will form a stack
# Further erosion takes place and a stump is formed which can only be seen at low tide

Rivers

Rivers in ‘bank full’ stage

It is the flow stage of a river in which the stream completely fills its channel and the elevation of the water surface coincides with the bank margins.

Channelization

Channelization is the process of changing the natural course of a river in order to make it flow in a specific path so as to reduce the possibility of flooding. In order for this to happen, various engineering methods are used to alleviate the problems of flooding.

Types of channelization

Channel managements are carried out to facilitating navigation, regulating the speed of river, protecting the river banks against erosion and controlling floods by managing the volume and speed of flow of water. There are 4 methods used, they are river re-alignment, river resectioning, vegetation planting and bank protection.

River re-alignment

The straightening of the river channels removes meanders and reduces the length of the river channel. It also increases the speed of flow, reducing friction. And because of this increase in the speed of flow, sediments get washed off easily. The river re-alignment involves the deepening, flattening and smoothening the river channels. An example of this is the Kallang and Singapore rivers. The advantages of this method it is that is able to hold more water. Thus reduces incidence of flooding in the upper part of the stream. Another advantage of this is that the speed of the river is able to carry flood water away quickly. However, the disadvantage of this method is that it is too costly and it cannot prevent large floods and it also increases the erosion of the river channels due to the increase in velocity.

Re-sectioning

Re-sectioning involves the widening and deepening of the channel it increases the channel’s ability to hold more water and decreases incidence of floods. Therefore, more surface runoffs enter the rivers. River banks and beds are replaced with cement and granite, this causes less friction between water and river bed and banks allowing the speed of flow to increase. The water flows away from the area faster. This method is usually used in urban areas to alleviate flooding.

Bank protection

Bank protection is built to prevent floods and reduces soil erosion along the banks. This process involves building artificial levees / dykes / embankments on the sides of river channel to increase the height of the river bank to contain flood waters. Walls of sand, stone, or concrete increase channel capacity to hold water but it is not very effective (built up of sediments on river bed, channel becomes shallower). Building gabions or revetments protects the river banks from being eroded while reducing the amount of sediments washed into rivers.

Planting Vegetation

Roots of trees and other plants hold the soil together firmly this protects the river banks, reduces amount of eroded sediments, Slows down the rate of surface runoff. It also prevents large amounts of water from entering river at one time as the roots of the trees absorbs the water in the river. The disadvantage of this however is that excessive shade prevents sunlight from reaching the river bed, killing aquatic plant and animal life. The destruction of habitats is due to the building of concrete banks. This is ineffective in urban areas and time is needed for these trees to mature.

Genetically Modified Food. [GM food]

Some of the words are linked to their Wikipedia page. Any question, comment in tag broad :)

Definition

GM food is food from plants that have been genetically altered to create desired qualities

These qualities include improved resistance to diseases and tolerance to herbicide or extreme water

Different From High-yielding varieties [HYV] !!!! Do not mix them up !

HYV are cross-breed. While GM food is genetically modified.

To make things clearer. Here are some pictures.

This is a picture of GM food. Genes from other living things [maybe from plants,fruit,animal etc.] are inserted into the plant.



This is an example of HYV. Mixing the pollen of the plants to create a better one.



An out come would be this: A seedless watermelon.

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Benefits
Increase Income for Farmers

Genetically Modified [GM] Crops are pest-resistance and therefore reducing damage of crops.

They do not need to spend money buying pesticide.

Expenses go down, Revenue Increase

GM crops are tolerant to extreme water

Which reduce loss during floods.

They are also created to stay fresh for a longer period of time

This enable farmers to sell their products in other country; increasing revenue.

Increase Food supply

GM crops are able to produce more crops compared to normal crops

e.g Normal crop- 100 ; GM crops- 200.

One Example of such crops is Super Rice.

Which is modified to produce double of what is normally produced

Improve nutritional value of food

GM food might be modified to have higher nutritional values.

e.g Golden rice have been modified with beta-carotene[ inactive form of vitamin A].

to supply the lack of vitamin A in rice diet in LDCs.

Due to the lack of vitamin A in the past,

1 Million children died and 350 000 became blind.

Golden rice can help reduce malnutrition cases.

Scientist are still try to use GM food as medicine. If they succeed we don't have to go through painful injections and eat bitter medicine ! :D

Reduce environmental pollution

Without GM food, Farmers would have to use pesticide to kill pests

This is NOT good ! It adds on to the pollution of this world.

GM food reduces the reliance on chemicals.

One Example is the pest-resistant plant, which remove the needs of pesticide

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Threat
Potential health risk

Allergic reaction.

Example-Lectin. → a protein used in beans

Prevents aphids from attacking potato. but some people are allergic to it.

For those who don't know what is aphids. They look like this:

The people fear of eating food that are not natural

European Union [EU] has banned the import and cultivation of GM food crops.

Even Zambia,a country facing food shortage, rejected GM food

GM food are usually not labeled, therefore the concern.

Loss of Biodiversity

Biodiversity is the range and variety of animals in the ecosystem

GM crops that are pest-resistance may kill other animals or insects that are not harmful and upset the ecosystem

e.g Monarch butterfly's caterpillar feeds on corn

The corn may have added toxin that may kill the butterfly.

Animals that may feed on the butterfly, lost their source of food as too many butterfly die

As a result, they all die... X(

Loss of natural species

Pollen form GM plants was carried by the wind or insects

to another place where natural plants are found.

Offspring of normal plant would now have the GM plants genes, if this continue there will be no more natural plants

and as a result kill animals feeding on them [refer to loss of biodiversity]

GM food crops may be herbicide-resistant.

Genes may be passed on to the weeds around those plant

Producing Super weeds

which are damn hard to get rid of.

Stronger herbicide have to be used to get rid of them

but they might absorb and become even stronger. :(