Transcript Ecology

Chapter 50
Ecology & The Biosphere
The Structure of
Ecosystems
#1 - Biomes
Biomes
 Biomes: a large region characterized by
a specific type of climate and certain
types of plant and animal communities
Biotic Factors
 Biotic Factors: the biological influences
on organisms within an ecosystem
 Birds, Trees, Mushrooms, Bacteria
Abiotic Factors
 Abiotic Factors: physical, or nonliving,
factors that shape ecosystems
 Climate (temperature, precipitation,
humidity, etc.)
 Wind, Nutrient Availability, Soil Type,
Sunlight, etc.
Together, biotic and abiotic factors
determine the survival and growth of an
organism and the productivity of the
ecosystem in which the habitat lives.
Terrestrial Biomes
The Freshwater Province…
Pronounced Lake Zones
Littoral zone: the area around the edge of
the lake that is shallow enough for rooted
water plants to grow.
Limnetic Zone: the deeper central portion
of the lake.
Profundal Zone: the zone beneath the
limnetic zone that is below the limit of light
penetration. The dark profundal zone can
only support heterotrophs.
Pronounced Lake Zones…
Benthic Zone: the zone
underlying the entire lake,
which comprises the basal
layer of sediment. This zone
is generally a mucky ooze
that is essentially anaerobic.
It mainly supports bacteria.
The Marine Province
About three-quarters of the earth’s
surface is covered with water, mostly
salty.
Neritic province: the part of the ocean
in the relatively shallow areas along
continents.
Oceanic province: the deepwater
open sea.
The Marine Province …
Littoral zone: along the coastline,
from the high-tide “spray zone” out to
a depth of 200 meters.
Euphotic zone: the zone through
which light penetrates.
Aphotic zone: the zone that is in
perpetual darkness.
The Oceanic Province
Contains the pelagic organisms, those that
drift in the open sea. They are mostly
restricted to the euphotic zone.
The abyssal region is the deeper water region
where depths can vary from 300 to nearly
11,000 meters.
Abyssal regions support benthic organisms,
bottom-dwelling scavengers.
Deep Sea Creatures
Tropical rainforest
distribution: equatorial
precipitation: very wet
temperature: always warm
characteristics: many plants & animals, thin soil
2005-2006
Desert
distribution: 30°N & S latitude band
precipitation: almost
temperature: variable daily & seasonally, hot & cold
characteristics: sparse vegetation & animals, cacti,
succulents, drought tolerant,
reptiles, insects, rodents, birds
2005-2006
Temperate Grassland
distribution: mid-latitudes, mid-continents
precipitation: seasonal, dry season/wet season
temperature: cold winters/hot summers
characteristics: prairie grasses, fire-adapted, drought tolerant
plants; many herbivores; 2005-2006
deep, fertile soil
Chaparral
Between desert & Grassland or ocean and forest
(think S California: mild winter, hot, dry summer)
Temperate Deciduous Forest
distribution: mid-latitude, northern hemisphere
precipitation: adequate, summer rains, winter snow
temperature: moderate warm summer/cool winter
characteristics: many mammals, insects, birds, etc.;
deciduous trees; fertile soils
2005-2006
Coniferous Forest (Taiga)
distribution: high-latitude, northern hemisphere
precipitation: adequate to dry (temperate rain forest on coast)
temperature: cool year round
characteristics: conifers; diverse
mammals, birds, insects, etc.
2005-2006
Arctic Tundra
distribution: arctic, high-latitude, northern hemisphere
precipitation: dry
temperature: cold year round
characteristics: permafrost, lichens & mosses, migrating animals
& resident herbivores
2005-2006