Tropical forestry

1. Tropical Forestry
SFB 358
Credit hour (2+0)
B.Sc Forestry (Fifth Semester)
Prabin Pandit
Lecturer
Purbanchal University
College of Environment and Forestry (PUCEF)
foresterpandit@gmail.com

2. What is Tropics/Tropical region?

3. The Earth
23.5 degree
Axis

4. Concept of Tropics/Tropical Region
0° Equator
Northern hemisphere
Southern hemisphere
Tropic of Cancer
Arctic Circle
23.5° S
23.5° N
66.5° N
66.5° S

5. Concept of Tropics/Tropical Region
0° Equator
Northern hemisphere
Southern hemisphere
Tropic of Cancer
Arctic Circle
23.5° S
23.5° N
66.5° N
66.5° S
Tropics/tropical
region

6. Tropics/Tropical Region

7. Distribution of Tropical Forest
Almost all of the world’s closed tropical forests
are found in 65 tropical countries (source: ITTO,2011)

8. Tropical Forest

9. Status of the World Forest
Source: FAO Global Forest Resources Assessment remote sensing analysis (2014)
Regio
n
Climatic
domain
Forest area (million
hectares) % of world
total forest
2010
World Boreal 1190 31
World Subtropical 330 8
World Temperate 630 16
World Tropical 1730 44
Total 3890 100
2010
1190
330
630
1730
31%
8%
16%
44%
0 500 1000 1500 2000 2500
Boreal
Subtropical
Temperate
Tropical
Status of World Forest
% of world total forest Forest area (million hectares)

10. Status of Tropical Forest
0
200
400
600
800
1000
1200
1400
1600
1800
2000
Africa Asia North and
Central
America
Oceania South
America
World
Status of Tropical Forest
Forest area (million hectares) 1990 Forest area (million hectares) 2000
Forest area (million hectares) 2010
Region
Climatic
domain
Forest area (million
hectares)
1990 2000 2010
Africa Tropical 590 580 560
Asia Tropical 310 290 280
North and Central
America Tropical 70 70 70
Oceania Tropical 70 70 70
South America Tropical 820 790 760
World Tropical 1860 1790 1730
Source: FAO Global Forest Resources Assessment remote sensing analysis (2014)

11. Status of Forest in the Tropics
Source: Hasan / WRI ;State of tropical forests (2020)
54%
17%
7%
5%
4%
13%
Amazon Congo Australiasia
Sundaland Indo-Burma Rest of the tropics
Sundaland; Penisular Malaysia, Sumatra, Java, Bomeo, and nearby island; Australiasia: New Guinea, Northern Austrilia and nearby islands
Share of primary forest

12. Source: Hasan / WRI ;State of tropical forests (2020)

13. Important Questions
 At what angle axis of the earth is tilted ?
 What are the latitude lines of the world?
 At what degree different latitudinal lines found ?
 What do you mean by Tropics / tropical region?
 What is tropical forest?
 How much area do tropical forest cover?
 Which is the world biggest rainforest?
 What is the share of amazon forest area among the tropical forest of the world?

14. Types of Tropical Forest

15. i. Tropical Moist Evergreen Forest
 Also called tropical rainforest.
 Located about 10 degrees north and
south of the equator. Where there is
very little seasonal variation and the
solar day is a constant length all year
round.
 The greatest expanses of equatorial
rainforest are found in lowland
Amazonia, the Congo Basin, the
Southeast Asian islands of Indonesia,
and Papua New Guinea.
 A rain forest is simply an area of tall, mostly evergreen
trees and a high amount of rainfall (more than 2,000
mm annual rainfall).

16. ii. Tropical Moist Semi-Evergreen Forest
 They are transitional forests between tropical wet evergreen forests (rain forest) and tropical
deciduous forests.
 They are comparatively drier areas compared to tropical wet evergreen forests (rain forest) .
 As the name implies, some trees in these forests exhibit a seasonal leafless period, with the
deciduous component comprising up to one-third of the upper canopy.
 The increased sunlight reaching the forest floor allows the growth of vigorous understory
vegetation not found in lowland equatorial forest.
 Such moist forest is found in parts of South America, the Caribbean, West Africa, and
Southeast Asia, especially Thailand, Burma, Vietnam, and Sri Lanka.

17. iii. Tropical Moist Deciduous Forest
 Tropical Moist Deciduous Forest also known as Seasonal tropical forest or tropical mixed
forest.
 Most canopy trees lose their leaves during the dry season.
 But the dry periods are of short duration.
 In this type of forest there is a distinct cooler dry season and a distinct wet season.
 These forests tend to be less diverse and more dwarfed in terms of tree size in comparison to
typical equatorial rainforests.
 Tropical deciduous forests are found in the large part of India, northern Australia and in
central America

18. iv. Littoral and Swamp Forest
 Littoral forests and Swamp forests are also called the wetland forests.
 Littoral forests are forests along the coast featuring salt - tolerant vegetation.
 Littoral forests occur in patches and narrow strips along the mainland coast.

19. iv. Littoral and Swamp Forest
 Mangroves forest are one of the swampy forest where
group of trees and shrubs found in the coastal intertidal
zone.
 Mangrove forest is found in silt-rich, saline (salty water)
habitats worldwide, generally along large river deltas,
estuaries, and coastal areas.
 Mangroves are evergreen trees and shrubs that are well
adapted to their salty and swampy habitat by having
breathing roots (pneumatophores) that emerge from the
oxygen-deficient mud to absorb oxygen.

20. v. Tropical Dry Evergreen Forest
 These forest are found in the areas where dry season is comparatively longer.
 The trees are dense, evergreen and short about 10 to 15 meters high.
 A complete canopy comprising small leaved evergreen trees of short boles and
spreading crowns with some deciduous emergent, without marked differentiation
of canopy layers.
 The East Deccan dry evergreen forests , Sri Lanka dry-zone dry evergreen forests and the
Southeastern Indochina dry evergreen forests (occurs in a broad band across northern and
central Thailand into Laos, Cambodia, and Vietnam.) are the three dry evergreen forests in the
world.
 This forest happens to be one of the driest because it is in the rain shadow.

21. v. Tropical Dry Deciduous Forest
 tropical dry deciduous forests also called monsoon forests.
 In tropical dry deciduous forests most canopy trees lose their leaves during the dry season.
 The period of drought when trees are leafless is 2–6 months.
 High light levels penetrate the under-storey of these forests for much of the year, and grass
species are common.
 In many regions tropical dry deciduous forests grade into savannah ecosystems.
 Most of the tropical forest found in Nepal is belongs to this category.

22. v. Tropical Thorn Forest
 The Thorn Forests are found in the semi-arid areas, where the rainfall is less than 70cm.
 The trees are low (6 to 10 meters maximum) and widely scattered.
 The vegetation in these forests is thorny trees and bushes.
 Acacias and Cactus are very prominent.
 Some grasses also grow in the rainy season.
 The leaves of the trees and shrubs found have thick and small leaves which helps in
minimizing evaporation.
 The plants are leafless for the majority part of the year and are scattered.
 The general length of the trees ranges between 6 to 10 meters, which is low as compared to
other forms of vegetation or forests.

24. Montane Forests
 "Montane Forest is ecosystem found in mountains”.
 In this region vegetation differs with altitude.
 Montane forests occur between the submontane zone and the subalpine zone.
 Montane forests in temperate climate are typically one of temperate coniferous forest or
temperate broadleaf and mixed forest.
 Montane forests in Mediterranean climate (dry summer climate) are typically mixed conifer
and broadleaf forests, with only a few conifer species.
 In Nepal, Monte forest are found in:
 Churia region to sub alpine zone.

25. Thank You