Biodiversity, Biodiversity, Human Human Impact, Impact,

and and ConservationConservation

Lecture 1: BiodiversityLecture 1: Biodiversity BiodiversityBiodiversity is the variation of lifeforms is the variation of lifeforms

within a given ecosystem.within a given ecosystem. Genetic Diversity: individual genetic variation Genetic Diversity: individual genetic variation

within a population and the genetic variation within a population and the genetic variation between populationsbetween populations

Species Diversity: the variety of species in an Species Diversity: the variety of species in an ecosystemecosystem

Ecosystem Diversity: the variety of the Ecosystem Diversity: the variety of the biosphere’s ecosystemsbiosphere’s ecosystems

An An EcosystemEcosystem is the sum of all the is the sum of all the organisms in a given area as well as the organisms in a given area as well as the abiotic factors with which they interact.abiotic factors with which they interact.

A A Biodiversity HotspotBiodiversity Hotspot is a relatively small is a relatively small area with an exceptional concentration of area with an exceptional concentration of endemic species and a large number of endemic species and a large number of endangered or threatened species. endangered or threatened species.

Endemic SpeciesEndemic Species: A species only found in : A species only found in one region or part of the world one region or part of the world

EcologyEcology is the study of the interactions is the study of the interactions between organisms and the environment.between organisms and the environment.

Understanding EcologyUnderstanding Ecology• Studying ecology will reveal the richness of the

biosphere.• Ecological interactions can determine both the

distribution of organisms and their abundance.• With this understanding, one will be able to help

conserve and sustain biodiversity.

Determining Species Determining Species Distribution and Distribution and

AbundanceAbundance 1) Environmental 1) Environmental

FactorsFactors TemperatureTemperature SeasonalitySeasonality

2)Amount and 2)Amount and Variability of Variability of PrecipitationPrecipitation

Dispersal contributes Dispersal contributes to this global to this global distribution of distribution of species.species.

Above: Biogeographic Above: Biogeographic realms indicating realms indicating distribution patterns distribution patterns due to continental due to continental drift and topographic drift and topographic land barriersland barriers

Flowchart of Factors Flowchart of Factors Limiting Geographic Limiting Geographic

DistributionDistributionUnderstanding the Flow

Chart:

Behavior Limits: refer to habitat Behavior Limits: refer to habitat selectionselection

Biotic Factors: mainly refer to Biotic Factors: mainly refer to predation and the presence or predation and the presence or absence of food resources but may absence of food resources but may also include parasitism, disease, or also include parasitism, disease, or competitioncompetition

Abiotic Factors: include temperature, Abiotic Factors: include temperature, water, sunlight, wind, and climate water, sunlight, wind, and climate conditionsconditions

Climate mainly determines Climate mainly determines the Distribution and the Distribution and

Structure of EcosystemsStructure of Ecosystems

Temperature and Temperature and precipitation in precipitation in addition with addition with physical geographic physical geographic features determine features determine the structure of the structure of terrestrial Biomesterrestrial Biomes

Introduction to The Introduction to The TropicsTropics

Tropics are the location of many Tropics are the location of many biodiversity hotspots because of their biodiversity hotspots because of their

unique structure and history that unique structure and history that resulted in species diversity. resulted in species diversity.

50% of the worlds species are found in 50% of the worlds species are found in the tropical rainforests.the tropical rainforests.

Tropical Rainforests as Tropical Rainforests as HotspotsHotspots

There are 3 main There are 3 main regions of tropical regions of tropical rainforestsrainforests• 1)The Americas1)The Americas• 2)Africa2)Africa• 3)Australasia3)Australasia

The Conservation The Conservation International has International has established global established global hotspots.hotspots.• An interactive map can An interactive map can

be found here: be found here: http://http://www.biodiversityhotspots.owww.biodiversityhotspots.org/Pages/default.aspxrg/Pages/default.aspx

Biodiversity is not Biodiversity is not limited to animal limited to animal species but plant species but plant species as well.species as well.

Tropical Rainforests Tropical Rainforests are comprised of 100-are comprised of 100-300+ species of trees 300+ species of trees pre hectare. And few pre hectare. And few trees are common, trees are common, while many are rarewhile many are rare

The Tropical The Tropical Rainforests have Rainforests have increased faunal increased faunal diversity and densitydiversity and density

Effects of Faunal GroupsEffects of Faunal Groups Direct contribution to species Direct contribution to species

richnessrichness Indirect effects on plant and animal Indirect effects on plant and animal

diversitydiversity Contribute substantially to total Contribute substantially to total

biodiversity of Rainforestsbiodiversity of Rainforests Contribute irreplaceable services such Contribute irreplaceable services such

as seed dispersal, seed predation, and as seed dispersal, seed predation, and seed pollinationseed pollination

In summary, the faunal composition In summary, the faunal composition effects how ecosystems functioneffects how ecosystems function

Like faunal groups effect Like faunal groups effect Tropical Rainforests, Tropical Rainforests,

marine ecosystems are marine ecosystems are affected by Coral Reefsaffected by Coral Reefs

Coral Reefs are among the most Diverse

Ecosystem• Coral Reefs are the richest in species

of any marine environment• Coral Reefs are the keystone species

of the marine environment– Note a keystone species is a species

whose presence has a disproportionate effect on the ecosystem and contributes to the diversity of the ecosystem. Without this species, there is a direct correlation to extinction in other species

Coral Reefs, The HotspotCoral Reefs, The Hotspot Coral Reefs only comprise Coral Reefs only comprise

0.2% of the Earth’s Ocean 0.2% of the Earth’s Ocean Surface and they almost Surface and they almost exclusively occur within the exclusively occur within the TropicsTropics

Abundance and Abundance and Distribution is strongly Distribution is strongly affected by temperatureaffected by temperature

The Current Distribution of The Current Distribution of Coral Reefs is shown to the Coral Reefs is shown to the right.right.-Caribbean-Caribbean

-Coast of Central America-Coast of Central America

-Indo-Pacific Waters-Indo-Pacific Waters

-East Coast of Australia-East Coast of Australia

Biodiversity is Biodiversity is Effected by Effected by

Several Biotic Several Biotic and Abiotic and Abiotic

Factors, but the Factors, but the Greatest Threat Greatest Threat to Biodiversity is to Biodiversity is Human ImpactHuman Impact