Download Forest Ecosystem and Function

Forest Ecosystem and Function
Temperate Forests of Naran, Pakistan
Types of forests
•Tropical rain forests - Hot and humid
region.
- Annual rain fall- 2000 to 4500mm.
-Found in south and central America,
westren and central Africa, South east
Asia, and some Islands of Indian and
Pacific Oceans
-Tropical forests are considered
important because it helps in recycling
water
Temperate Forests
• Cold in winter and warm and humid in
summer
• Annual rain fall is 750 – 2000 mm.
• Sol is rich.
• Found in Western and Central
Europe, eastern Asia and eastern
North America.
Temperate Forests of Nathiagali, Pakistan
Temperate Forests of Kaghan Valley
Coniferous forests
• Many coniferous trees are found in
this region like
spruce, fir, pine etc.
• Found in northern parts of northern
America,
Europe & Asia.
• The soil in these forests is acidic and
humus rich
Sub-Tropical Scrub Forests, Margalla Hills
Sub-Tropical Pine Forests,
Margalla Hil
Grass lands
Grasslands
• Grasslands are regions where average
precipitation is high (250 – 1500 mm) for grass
and for trees to grow.
• Rain fall are erratic and uncertain in these region
• Regions found in central & south America,
subequitorial Africa & South Australia, south
India
• Soil rich and deep ideal for grasse.
Alpine pastures of deosai, skardu, Pakistan
Thar Desert
Thar is the Largest Desert Of
Pakistan. It is situated in the
province of Sindh. This desert
also enters the boundry of India
therefore it is one of the largest
deserts of Asia. Thar desert in
Pakistan spreads over an
extensive area in Ghotki, Sukkar,
Sanghar, Mirpur Khas and
Tharparkar districts. The desert
consist of barren tracts of sand
dunes covered with thorny
bushes, mostly acacia. The
desert is separated from
irrigated area by the bed of the
Eastern Nara. The Cholistan
Desert adjoins the Thar desert
spreading into Pakistani Punjab
province. Thar desert of Pakistan
and India is the 9th largest
desert of the world. The total
length of Thar desert in Sindh
(Pakistan) and Rajhistan (India) is
200,00
DESERT
A desert is a land scape form or
region that receives very little
precipitation.>250mm per annum.
Coastal Forests, near Karachi, Pakistan
Mangrove Forests, Karachi, Pakistan
MOUNTAIN
Mountain is land form that extends
above the surrounding terrain in
unlimited area.
CHARACTRISTICS
• Mountain cover the 20% of land area.
• Going up the mountain is similar to
moving from equator to north pole.
• Mountain are the reseviors of water.
• A big bank of Biodiversity.
The following forest types of
Pakistan are found in Pakistan.
•Littoral and swamp forests
•Tropical dry deciduous forests
•Tropical thorn forests
•Sub-tropical broad -leaved evergreen forests.
•Sub- tropical pine forests
• Himalayan moist temperate forests
•Himalayan dry temperate forests
•Sub alpine forests
•Alpine scrub
Natural forsets and
manmade
tree
plantations
cover
4.224 million ha, or
4.8% of of the land
area
in
the
country.Anonymous
1992, Amjad et al
1996. Agriculture ,
both irregated and
non- irrigated, is
practiced on 20.58
million ha, or 23.4 %
of the land area, and
live stock grazing on
28.509 million ha, oe
32.4 %, consists of
snow, glaciers, rock,
deserts tidal flats,
water bodies river
beds, lakes, dames,
towns cities and so
forth. The nonproductive use of
most of the land
area is due to he arid
climate.
Distribution of Pakistan`s forests
Forest ecology effects,
All sources categories
•Forest health
• T & E species,
•Timber and wood products
•Cultural resources
•Soils
• Esthetics & reaction
•Water
•Aggroforestry & spl. Forest Prod
• Fish & wild life
Forest floor
Ecosystem consists of …
Communities of animals(living) things:
Plants, animals, microbes, et al.
Inanimate stuff (rocks, soils, grasses,
chemicals).
Exchange matter and energy:
within the system
Between systems
Systems Interact and are independent
Ecosystem structure
(size and arrangement of planta and animals,
dead stuff ft al)
OPERATIONAL Env.
Ecosystem function
(The operational environment exchange
of matter and energy)
Operational Environment
the physical environment around a living
oragnism;governs how ecosystem interact
Light
Mechanical
Plant
Heat
Chemical
Oprerational environment effects
every thing.
•Growth
•Disease
•Insect
•Reforestation
•Distribution of plants
Oprerational environment effects
every thing.
•Big drivers
Not so big drivers
-Climate
– timber harvest
-Elevation slope aspect -Silviculture
-Geology and soils
- Land conversion
-Land conversion
-Microclimate
-Fire policy
- Land slides
-Floods
- Floods
-Biota
– Plants and animals
Which leads to…
Why are plant species found where they
are found?
Answer: Its evolved adaptation to its
surrounding operational
environment
And….
Ecological communities
• Plants and animals are occurring together in
a coherent group because of their aptations
to each other and the surroundings
Environment
• (Communities become ecosystems when we
include processes behind interaction and
interdependency)
•Temperature and water availability
are two big drivers in determinig forest type:
Fire is important …
Geology, e.g. serpentine soils, may be locally
important
Natural forces (disturbances) modifying
the operational environment….
•wind throw
•Earth quake
•Root disease
• Land slides
• Global climate change
• floods
• and ..
Fire natural and human caused , is a mjor
force drive plant succession in forests..
Some trees and shrubs are adapted for
fire, while others are not.
FIg
Forest succession
Community changes, because plants
change the operational environment
Forest succession
Primary succession
Secondary succession
Following big distribution
After initial plant
Early seral plant species
Late seral species
Best in full sun light conditions
Best tolerant shade and other
understory conditions
Forest succession
• The changed
operational
environment
may help
perpetuate the
existing plant
community, OR
Set the stage
for the next
community.
Succession in an even aged Fir
forests
Succession may have many end points
• 45
year
old Fir
stand
• Root
disease
s and
bark
beetles
affecte
d out
come
What about human induced
ecosystem change?
?
Harvesting affects operational environment here…greatly
increased light, heat, water, chemical turn over; Sol
compaction?, Mycorrhizal effects?
Thinning effects: Less increase in light, heat, water, nutrient turn over;
Mechanical damage to leaves tree? Soil
compaction?
Productivity…what makes the
whole work done
?
Oceanic
production by
the process of
Photosynthes
Terrestrial
production
Trophic levels - plural-Noun
Each of several hierarchical levels in
an ecosystem, consisting of
organisms sharing the same function
in the food chain and the same...
The trophic level of an organism is the position it occupies in a food
chain. The word trophic derives from the Greek τροφή (trophē)
referring to food or feeding. A food chain represents a succession of
organisms that eat other…
First
trophic
level. The plants
in this image,
and the algae
and
phytoplankton in
the lake, are
primary
producers. They
take
nutrients
from the soil or
the water, and
manufacture
their own food
by
photosynthesis,
using
energy
from the sun.
Trophic levels
• T1 producers
•
T2 Herbivores
•
T3 Primary carnivores
•
T4 Secondary carnivores
•
T5 Decomposers
Energy flows are like log processing:
there`s an attempt to maintain
maximum value at every step,
orecologically, nature tends to fill all
niches with communities.
Overview
The three
basic ways
organisms
get food are
as producers,
consumers
and
decomposers
.
The T1 level
The environmental drivers determining productivity
species location also determine productivity. Soils
management is very important.
Fig.
Nice little T2
herbivores at work…
Spruce bud worm may be a
serious pest on over stocked
with firs.
Second trophic level
Rabbits eat plants at the first
trophic level, so they are primary
consumers.
Fig
Fourth trophic level
Golden eagles eat foxes at the
third trophic level, so they are
tertiary consumers.
Decomposers T5 are essentials within a forest
ecosystem for nutrient cycling…
Decomposers includes larger insects, and a fanastic variety of
microscopicinsects, bacteria, fungi and actinomycetes.
The fungi on this tree feed on
dead matter, converting it
back to nutrients that primary
producers can use.
Mycorrhizae
•Mutual benefits
-Greatly expanded root net-work
(increased).
- Esential hormones
- Pathogens protection- Attracts microscopics insects for bu
poop near roots
-- fungal get food from tree
- White is mycorrhiza
What happen within and around a primary root…?
Fig
Ecosystem resilience & suatainability
Our forest
ecosystems
are adapted
to various
types of
natural
disturbance
s.s
Undersatnding Resiliencey: Diturbance
does not exceed system ability to
recover:
•Self healing
•Redundancy
•Genetic diversity within and between
species
•Refugia.
Redundancy is a form of dismissal
Redundancy is a form of dismissal. A genuine
redundancy only arises in three very narrowly
defined circumstances:
the closure of the business,:
the closure of a particular workplace – for
example an academic unit, department,
course, unit or office/building:
a reduction in the need for employees – the
test being not whether an employer needs
fewer employees, but whether it needs fewer
employees to do work of a particular kind. This
could be due to restructuring.
Sustainability
•Sustainability is meeting present
needs without compromising the
future.
•Not pushing an ecosystem beyon its
ability to recover
Practices that drastically alter the operational environment,
such as terracing for site preparation,can be successful,
though not politically acceptable.
fig
Legacies (The local spare parts bin)
As long as enough undisturbed ecosystem
pieces remain, the system will recover
Sustainability is like good equipment
operation & maintenance…. Even better, with
good harvesting, forst ecosystems can quickly repair themselves.
The right machinery and a knowledgeable operator are very
important……. As is leaving enough of the right pieces intact.
Within stands and across landscapes,
sustainability takes human in genuity working
with Mother nature.