Post on 11-Apr-2017
transcript
Dr. B. Victor
Bio =
BioBiodiversitydiversity
What does “Bio” mean?
BioBiodiversitydiversity
Diversity = Variety
What does “Diversity” mean?
Why protect biodiversity ?
MORAL right to exist, stewardship (heritage), unnecessary waste immoral ECONOMIC valuable resources now and in the futureECOLOGICAL maintain local to global ecosystem health LEGAL have to by law
Human impact on Global Biodiversity
Human activities have altered the world’s terrestrial, freshwater and marine ecosystems throughout history.
In the last 50 years, there was “a substantial and largely irreversible loss in the diversity of life on Earth” (Millennium Ecosystem Assessment, 2005).
The number of species at risk of extinction – 16,306 species of plants and animals listed as threatened globally – clearly reflects this loss of diversity.
Biodiversity – plants, animals, microorganisms and the ecological processes that interconnect them – forms the planet’s natural productivity.
The world is a living system where…
Everything is connected and…. Everything is interdependent and…. Sustained in a dynamic balance. Matter and energy may change form, but
they do not disappear.
A Basic Equation for Life
Seeds + Soil + Nutrition + Water + Sun = Food
Natural cycles in the world’s ecosystems help deliver nutrition and water to the soil, and microbes in the soil help capture and process those materials so they are available to be taken up by plants. Plants become a part of the food chain and are eaten by other living things.
Massive biodiversity loss is essentially irreversible Each species is the product of a unique, non-
reproducible history Paleontology shows that it takes about ten
million years to recover previous levels of species diversity after a period of mass extinction, and the new biodiversity strongly differs from that lost
The Millennium Ecosystem Assessment : five main causes of biodiversity loss habitat change, climate change, invasive alien species, overexploitation and pollution. The Assessment argued that the loss of the
species and the progressive homogenization of many ecosystems is one of the main threats to the survival of the natural systems.
Introduction
The term BIODIVERSITY was first coined by the entomologist E.O. Wilson in 1986.
Biodiversity is the heritage of million of years of evolution.
Diversity is a basic property of life. The striking feature of Earth is the existence
of Life and the striking feature of Life is its Diversity.
Biodiversity allowed the advent of modern civilizations, but… Plant and animal domestication often
involves a reduction in biodiversity through artificial selection
• Industrialization and modern technology provide humankind with increasing control over, and independence from, nature
Plants begininvadingland
Evolution and expansion of life
First fossilrecord ofanimals
Plants invade the land
Age of reptiles
Age of mammals
Insects and amphibians invade the land
Modern humans(Homo sapiens)appear about2 secondsbefore midnight
Recorded humanhistory begins1/4 secondbefore midnight
Origin of life(3.6–3.8 billionyears ago)
noon
midnight
Biodiversity is the measure of the number, variety and variability of living organisms.
Variety - the number of different types.Quantity - the number or total biomass of any one type.Distribution - the extent and nature of geographic spread of different types.
What is biodiversity?
Biodiversity includes diversity within species, between species and among
ecosystems.
Significance of biodiversity
Biodiversity is the sum of life on earth and includes genetic, species and functional diversity.
The status and trends in biodiversity reflect the health of the ecosystems that support and enrich human life.
The Earth is home to a tremendous biological diversity
This “biodiversity”, which includes: The millions of different species The diversity of their genes, physiologies, and
behaviors The multitude of their ecological interactions The variety of the ecosystems they constitute
This biodiversity, which is the result of more than 3billion years of evolution, is under serious threat today
Biodiversity
• Variety of living things, number of kinds• Ecological diversity
– different habitats, niches, species interactions• Species diversity
– different kinds of organisms, relationships among species
• Genetic diversity– different genes & combinations of genes
A B
Which do you like better?
A B
Which do you like better?
A B
Which do you like better?
What is biodiversity?
The spectrum of life on earth, in terms of variation in genes, populations, species, ecosystems, interactions among them.
Biological Diversity
Genetic diversity – the genetic variation among individuals in a speciesSpecies diversity – the number of different species in a given areaEcosystem (Habitat) diversity – the variety of interactions among organisms in a community (or the variety of ecosystems on Earth)
Biodiversity, the variety of life more interactions COMMUNITY POPULATION INDIVIDUAL GENOME CHROMOSOME GENE ENZYME more biological units
Biological Diversity
Biological diversity organization
Levels of genetic organization
Gene Text sequence
Chromosome
Chapter
Genome
Gene pool
Variation within genes alleles & haplotypes
Variation within individualsindividual heterozygosity
Variation within populationsallele frequencies, average heterozygosity, average number of polymorphic alleles and loci.
Variation among populationsdifferentiation and genetic distance (pairwise and average)
Genetic diversity
Species diversity
It represents the different types of plants, animals and other life forms within a region.It is a dynamic property and changes over space and time.The number of species and their relative abundances depend on the size and geographic area of the ecosystem.Species diversity is an indicator of the biological richness/stress of an ecosystem.
Ecosystem diversity
It is the variety of different habitats/ecosystems in a particular area ( e.g.. wetland, woodland, grassland).The ecosystems of the world are maintained by their biodiversity.Every ecosystem can be characterized by its own species composition.The ecosystems differ in features such as physical structure, temperature, water availability and food types.
Ecosystem Characteristics
Biological structure, composition.Physical structure, composition.Major vegetation types.Successional stages.Rare or specialized communities (or otherwise at risk.)Soil and air resources.Water quality.Stream flows, streambanks, shorelines, lakes, wetlands, riparian areas, floodplains.Principal ecological processes, invasives.
Ecosystem Characteristics
Major vegetation types and developmental stages.Rare and unique habitats.Species richness, diversity, distribution.Narrow endemic, geographically restricted, or rare species.Spatial structure of populations.Invasives.Keystone species or ecological engineers.Landforms adjacent to stream channels.Wetlands.
Structure Characteristics
Proportion and distribution of vegetation types and successional stages.Density of large trees per acre.Landscape patch dynamics.Stream habitat complexity.Riparian structure.Tributaries, lake morphometry.Soil productivity, soil compaction layers.Percent particulate matter in air.Stream diversions and impoundments.
Processes Characteristics
Fire, landslides, flood types, frequencies, severities, patch size, landscape pattern.Successional pathways.Stream and lake temperature regimes.Riverine flow regimes, sediment transport.Nutrient cycling.Rate and extent of invasion by exotics.
Diversity of organisms
How many different species are there? The number of species identified and named is
more than 1.7 million, including: 950,00 species of insects 270,000 species of plants 19,000 species of fish 10,500 species of reptiles and amphibians 9,000 species of birds 4,000 species of mammals
The rest includes mollusks, worms, spiders, fungi, algae, and microorganisms.
Biodiversity: # of species estimates
Most estimates of the total number of species on Earth lie between 5 million and 30 million.
Of this total, roughly 2 million species have been formally described; the remainder are unknown or unnamed.
Biodiversity Attributes
1.Scales of diversity
Alpha – number of species in a given plot or area
a
c
d
ab
c c
aa
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a b
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2.Scales of diversity
Beta – species turnover across an environmental gradient
16.14
3.Scales of diversity
Gamma diversity: the total biodiversity within a landscape.
Gamma diversity is a function of local or ‘within habitat diversity’ (alpha diversity) and differences in species composition or ‘turnover’ of species, between habitats or localities (beta diversity ).
Scales of diversity
Types of biodiversity measures
What is being measured? - measures of numbers of things (e.g., number of
species - measures of processes (e.g., primary productivity) - measures of system properties (e.g., resilience) What scale? - genetic - species - community - ecosystem - landscape
Species Richness (S)
The total number of different organisms present. It does not take into account the proportion and distribution of each subspecies within a zone.
Simpson Index (D)
A measurement that accounts for the richness and the percent of each subspecies from a biodiversity sample within a zone. The index assumes that the proportion of individuals in an area indicate their importance to diversity.
Simpson's index: D = sum(Pi2) The first step is to calculate Pi, which is the
abundance of a given subspecies in a zone divided by the total number of subspecies observed in that zone.
Shannon-Wiener index (H)/ the Shannon index / the Shannon-Weaver index This measurement takes into account subspecies
richness and proportion of each subspecies within a zone.
The first step is to calculate Pi for each category subspecies. Then multiply this number by the log of the number. While you may use any base, the natural log is commonly used. The index is computed from the negative sum of these numbers.
H = -sum (Pi log [Pi]) Using species richness (S) and the Shannon-
Wiener index (H), you can also compute a measure of evenness:
E = H/ log (S)
Biodiversity
Biodiversity maintains the health of the earth and its people.It provides us with food and medicine and contributes to our economy.It tells us a lot about the health of the biosphere.The greater the variety of species, the healthier the biosphere.
Biodiversity – Hierarchy
Biodiversity Is determined By:
Species richnessSpecies evennessSpecies compositionSpecies interactionTemporal and spatial variation
Species richness is the number of species in a given area.
High-, medium- and low Diversity
Why is biodiversity important?
Regulation of climate and biogeochemical cycles, Hydrological functions, Soil protection,Crop pollination,Pest control,Recreation and ecotourism Ecological resilienceWildlife habitat and diversity Traditionally free benefits to society or “public goods”Scale is variable from local to global benefits
What do we get from biodiversity?
OxygenFood
Clean WaterMedicine
AestheticsIdeas
Biodiversity is dynamic
Biodiversity is not static, but constantly changing.Biodiversity is increased by genetic change and evolutionary processes and reduced by processes such as habitat degradation, population decline, and extinction.
Earth's five mass extinctions Earth is experiencing a sixth mass extinction today.
Anthropogenic Impacts
• By the end of the 21st century, we may have lost two-thirds of the species on Earth
• To date, about 50 percent of the planet's natural habitats have been cleared for human use, and another 0.5 to 1.5 percent of nature is lost each year
Principal causes of extinction
73% - Destruction of habitat 68% - Displacement by introduced species 38% - Alteration of habitat by chemical `
pollution 38% - Hybridization of species (plants) 15% - Over-harvesting
The main threats to biodiversity
Endangered and Extinct Species
Extinction, the elimination of a species from Earth, occurs when the last individual of a particular species dies.
Extinction is a natural process – 99.95% of all the species that have ever lived on Earth are extinct today.
However, human activities can speed the process - extinctions today are occurring at 100 to 1000 times faster than the natural rate.
Endangered and Extinct Species
Endangered species are in imminent danger of extinction throughout all or part of their range.
Threatened species have low population sizes and are likely to become endangered in the near future.
Characteristics of Endangered SpeciesEndangered species have one or more of these characteristics that make them vulnerable to extinction: limited natural range low reproductive success specialized feeding requirements large territory requirement
Extinctions can be caused by: ·natural processes (e.g. fires, hurricanes,
droughts); excessive harvesting of particular species of
economic value; impacts of alien invasive species including
diseases; the impacts of various environmental pollutants; changes in climate; knock-on effects from extinction of essential
companion species (e.g. pollinators, fruit or seed dispersers, obligate parasites or symbionts);
Human activities threatening biological diversity: Habitat destruction, fragmentation, and degradation Invasive species Pollution Overexploitation
Habitat Fragmentation Habitat fragmented into smaller “patches The patches grow further apart, more isolated,
organisms can’t move among them. Fragments reside in a “matrix” of anthropogenic,
disturbed habitat (farmland, subdivisions, etc)—often inhospitable to native species.
those Species obligated to the remaining habitat patches decline, those able to move among patches and utilize the human-dominated matrix hold on.
Generalist species able to use patch, edge, and matrix increase (deer, raccoons, many weeds).
Fragmentation most easily observed in forest habitat is caused by human activities. Anywhere that humans transformations cut up continuous habitat.
“Edge Effect” and edge vs. interior species.
Habitat Destruction
Habitat destruction, fragmentation, and degradation is the leading cause of biodiversity decline.
All in the name of progress?
Invasive Species Biotic pollution is the introduction of a foreign species into an area where it is not native
Other names for these: Invasive Species Exotic Species Foreign Species Non-native Species
Pollution
Acid deposition Global warming Toxic chemicals Plastics
Overexploitation
Over-hunting – unregulated hunting Poaching – illegal hunting Over-fishing – harvesting faster than the stocks can replace themselves Over-collecting – collecting live organisms for zoos, pet stores, research etc.
Homogenization
Homogenization is the process whereby species assemblages become increasingly dominated by a small number of widespread, human-adapted species.
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AnthropogenicHomogenization
Exotic speciesHomogenization
Biodiversity affects human well-being
Human activitiesGlobal
changes
BiodiversityEcosystem processes
Ecosystem services
Links between biodiversity, climate change and Human well-being
Links between biodiversity, climate change and ecosystem services
Aestheticvalue
Ethical value
Social value
Productive value
Consumptive value
Biodiversity Value
Values of biodiversity
Values ofbiodiversity
Ecological values
Economic values
Cultural values
“Value” of Biodiversity
1. Market values 2. Non-market values 3. Ecosystems services Measured in terms of ecosystems
function Focus on biologically mediated flows of
energy and materials
Biodiversity Value : Ecological values
All living creatures are supported by the interactions among organisms and ecosystems. Loss of biodiversity makes ecosystems less stable, more vulnerable to extreme events, and weakens its natural cycles.
Economic values
: A biologically diverse natural environment provides humans with the necessities of life and forms the basis for the economy.
Every thing we buy and sell originates from the natural world.
Cultural values
Most people feel connected to nature, often for reasons hard to explain. Some feel a strong spiritual bond that may be rooted in our common biological ancestory. Others are inspired by its beauty. Human cultures around the world profoundly reflect our visceral attachment to the natural
world. Thus cultural diversity is linked to Earth’s
biodiversity.
Ecosystem Services
New ways of thinking Ecosystem Services: the benefits people obtain from ecosystems
RegulatingBenefits obtained from
regulation of ecosystem processes
• climate regulation• disease regulation
• flood regulation
ProvisioningGoods produced or
provided by ecosystems
• food • fresh water• fuel wood
• genetic resources
CulturalNon-material benefits
from ecosystems• spiritual
• recreational • aesthetic
• inspirational• educational
SupportingServices necessary for production of other ecosystem services
• Soil formation• Nutrient cycling
• Primary production
Many human activities disrupt, impair, or reengineer ecosystems every day including:
runoff of pesticides, fertilizers, and animal wastes pollution of land, water, and air resources introduction of non-native species overharvesting of fisheries destruction of wetlands erosion of soils deforestation urban sprawl
Linkages among Biodiversity, Ecosystem Services, and Human Well-Being
Major Concepts
Most species are moderately abundant; few are very abundant or extremely rare.
A combination of the number of species and their relative abundance defines species diversity.
http://www.oceansatlas.org/http://news.nationalgeographic.com/news/
Molles 2007
Global changes
Climatic change
Land use change - type - intensity
Species invasions
Loss of biodiversity
PollutionOver-harvest
http://www.ourworldfoundation.org.uk/polar.jpg
http://library.thinkquest.org/
ADVERSE EFFECTS ON ECOSYSTEMS decline of forests, due to air pollution and acid deposition; loss of fish production in a stream, due to death of
invertebrates from copper pollution; loss of timber growth, due to nutrient losses caused by
mercury poisoning of microbes and soil insects; decline and shift in age of eagle and hawk (and other top
predator) populations, due to the effects of DDT in their food supply on egg survival;
losses of numbers of species (diversity) in ship channels subjected to repeated oil spills;
loss of commercially valuable salmon and endangered species (bald eagle, osprey) from forest applications of DDT.
Percentage of birds, mammals, fishes and plants/ Total number of species disappearing
(after Pimms et al., 1995 in Chapin et al., 2000)
The role of biodiversity in global change
Biodiversity and Sustainability
The biodiversity of an ecosystem contributes to the sustainability of that ecosystem.
Higher/more biodiversity = more sustainable. Lower/less biodiversity = less sustainable.
High biodiversity in an ecosystem means that there is a great variety of genes and species in that ecosystem.
Preserving Earth’s Biological Diversity
Ex-situ Conservation
Ex-situ conservation means “off-site” conservation. The species of plants and animals to be protected
are removed from the natural habitats and are placed in the safer areas under the control of man.
Botanical gardens, zoos and the arboreta are the traditional methods of ex-situ conservation.
Germ plasm banks or Seed banks (also Gene banks) are some other methods of ex-situ conservation.
In-situ Conservation
In-situ conservation means “on-site” conservation i.e. protection of species within the natural habitat of the species of animals and plants.
It includes protection in the wildlife sanctuaries, national parks and biosphere reserves etc. that have been formed to protect threatened and even rare species.
In-situ Conservation
In India we have 608 protected areas. · National Parks: 95 · Biosphere Reserves: 13 · Wildlife Sanctuaries: 500In India, there are four internationally recognized
Biosphere Reserves: Nilgiri, Gulf of Mannar, Sunderbans and Nanda Devi (Man and Biosphere Programme of UNESCO).
In Tamil nadu we have: National parks: 5 Wild life sancturies: 20 Biosphere reserves: 2
Biodiversity Hotspot Zones
British ecologist Norman Myers gave the concept of ‘biodiversity hotspots’ in 1988.
There are 25 hotspots on a global level. Out of the 25 hotspots, 11 have lost at least
90% of their natural vegetation. The TWO Indian hotspots viz. the eastern
Himalayas and the western Ghats are rich in flora, reptiles amphibians butter flies and some mammals.
Indo-Burma hotspot region
This region extends from North-east India to Burma and has a rich treasure of biological resources.
The region has a remarkable diversity of fresh water turtles and bird species (over 1300 species).
A number of dipterocarps, orchids and ginger 11 species are present in this region.
The Himalayan Hotspot
The Himalayan Hotspot has over 10,000 plant species of which 31.6 5 are endemic.
These include pines, firs, spruces, rhododendrons and variety of orchids, mosses and ferns.
A number of birds and mammals including vultures, tigers, elephants, rhinos and wild water buffaloes exist in the Himalayas.
Western Ghats and Sri Lanka
Western Ghats and Sri Lanka is one of the richest biodiversity areas with a high rate (52%) of endemism of plants species.
A number of unique and rare plants and ferns are present in this hotspot.
Biodiversity Act of India (2002)
The Government of India approved biodiversity bill in December 2002 which became an ACT known as Biological Diversity Act of 2002.
Later, Biological Diversity Rules, 2004 were formulated as a step towards conservation of biodiversity.
According to this act, any one who destroys biodiversity in any way or takes it away for commercial utilization or any other purpose without approval of authorities is liable to be imprisoned for up-to five years or to pay a fine of Rs.10 lakhs.
Some closing thoughts
How do we restore ecological balance and meet human needs? Don’t deplete non-renewable resources Use renewable resources efficiently and
sustainably Don’t create persistent toxicity Respect and protect biodiversity Organic farming provides the foundation for
restorative agriculture.
Biological Diversity
Biological Diversity
Biodiversity quotes
Every country has three forms of wealth: material, cultural and biological. The first two we understand well, because they are the substance of our everyday lives. The essence of the biodiversity problem is that biological wealth is taken much less seriously. . . ..” -EDWARD WILSON, The Diversity of Life (1992).
“Harmony with the land is like harmony with a friend; you cannot cherish his right hand and chop off his left. The land is one organism. Its part compete with each other and co-operate with each other. To keep every cog and wheel is the first precaution of intelligent thinking”
– Aldo Leopold
We remember we depend on each other, live and let live.