what is tropical dry forest?

Dry Tropical Forests [Rain Green vegetation]
·India
·Indochina
·W. Africa & W. Madagascar
·Southern Africa
·S. Amer. N & S of Amazon, C. Amer. & W. Indies
·N. Australia



- climate

· wet-dry tropical climate due to seasonal alternation between dominance by moist air of intertropical convergence zone during summer solstice &

dry air masses of subtropical-high belt during winter solstice

· note: ITC migrates to most northly position at summer solstice

· a large soil-water shortage occurs, especially severe during the hottest time prior to onset of rains



Monsoon climate

W. India
Burma
Bangladesh
C. & W. Africa (e.g., Sierra Leone)
S. Brazil

Þ hi and low pressure systems on continental interior
Þ extreme peak of rainfall during high-sun period (June/July - N)
Þ well developed dry seasons at low-sun (Dec-Mar - N)

This forest type typically experiences an annual hard dry season.
The average rainfall is sufficient enough to promote growth of trees,
but these tree and plant species must be able to withstand periods of
low precipitation and moisture.

Many of the tree species in dry forest are also deciduous. During the driest
months these species will drop their leaves much in the same manner that
northern deciduous forest species loose their leaves in the fall and winter.

This dry season leaf-drop reduces the water needs of the plant, as there is
no evapotranspiration through the leaves. Much of the dry forests of
Mexico and Central America have been converted into cattle ranches and
planted in exotic grasses.

These introduced plant species provide forage for livestock, but in
turn, change the habitat, and displace native forest species. These native plant
species are what comprise the forest habitat needed for both the plants and
animals that form the dry forest ecosystem.

The tropical and subtropical dry broadleaf forest biome, also known as tropical dry forest, is located at tropical and subtropical latitudes. Though these forests occur in climates that are warm year-round, and may receive several hundred centimeters of rain per year, they deal with long dry seasons which last several months and vary with geographic location. These seasonal droughts have great impact on all living things in the forest. Deciduous trees predominate in most of these forests, and during the drought a leafless period occurs, which varies with species type. Because trees lose moisture though their leaves, the shedding of leaves allows trees such as teak and mountain ebony to conserve water during dry periods. The newly bare trees open up the canopy layer, enabling sunlight to reach ground level and facilitate the growth of thick underbrush. Trees on moister sites and those with access to ground water tend to be evergreen. Infertile sites also tend to support evergreen trees. Three tropical dry broadleaf forest ecoregions, the East Deccan dry evergreen forests, the Sri Lanka dry-zone dry evergreen forests, and the Southeastern Indochina dry evergreen forests, are characterized by evergreen trees.

Though less biologically diverse than rainforests, tropical dry forests are home to a wide variety of wildlife including monkeys, deer, large cats, parrots, various rodents, and ground dwelling birds. Mammalian biomass tends to be higher in dry forests than in rain forests, especially in Asian and African dry forests. Many of these species display extraordinary adaptations to the difficult climate.

This biome is alternately known as the tropical and subtropical dry forest biome or the tropical and subtropical deciduous forest biome. Locally some of these forests are also called monsoon forests, and they tend to merge into savannas.