Richness = number of species present Evenness = relative abundance Composition = particular species present Interactions = non-additive affects
Here’s another way to look at earth – a bit more conceptual, but I’ll walk through it. Understanding how to make human endeavor more sustainable ecologically – most important question. Human activities Global change s - affecting biodiversity – richness, or # of species, abundances (not just are they there or not, but how many individuals?), composition – which types of species (e.g., grasses, or trees? Alligators or snakes?), and interactions (how do they influence each other – who is eating whom? Who is helping whom?). All this is changing and trying to deal with the causes of these changes is the realm of conservation. Looking at species as responding to changes in the environment, wrought by man. But the biota isn’t just a passive pile of flesh and cellulose getting batted about by the winds of change. In reality, the biota drive ecosystems. All that plant growth is what generates the energy other organisms use to grow, all those bacteria and fungi decomposing detritus – they are the ones responsible for breaking down old organic compounds and freeing up the nutrients so plants can keep growing, they are the ones responsible for building up rich soils, all those animals eating plants and other animals, they are the ones that grow big enough that we find it worth our time to kill and eat them to sustain ourselves. In that sense, biodiversity affects ecosystem processes – and ecosystem goods and services, things that benefit mankind. Some obvious – food, fuel, building materials, medicinals = goods. Relatively easy to assign a dollar value to them. Some water purification, natural flood control, pollination of crops, regulation of climate – we’re just beginning to understand. Processes that haven’t typically been accounted for in cost-benefit analyses during conversion of land from natural ecosystems. MVP vs. MFP: Conservation biologists, and even federal legislation like the endangered species act, typically talk in terms of minimum viable populations of a species – that is, what’s the smallest population size that is likely to persist for some set amount of time, say 100 years. To understand this other part of the equation, however, we need a very different perspective. We need to think in terms of minimum FUNCTIONAL populations of species: How many individuals are necessary to support a population large enough to fulfill an important ecosystem service? If a species was once very abundant and provided important ecosystem services, it doesn’t have to be globally extinct to cause major disruption to human activities. Just ask the people who used to fish for cod on the east coast. The big question is if and how the changes in biodiversity resulting from human actions will come back and bite us in the butt. Can we keep our species and eat them (and their habitats) too? To my mind, this question of sustainability is probably the most critical one of our time. Part of the reason I got into science was the feeling that people’s activities were just a small part of what is going on in the world – that to understand how the world is REALLY working, we need to understand processes that set the context for the human endeavor – the chemical, biological, and physical forces that shape the way the earth works. The type of global change most influencing a given region or ecosystem type will determine , these scenarios could be equally important as the linked traits in determining ecosystem properties. Understanding how communities will change in response to stressors and how altered communities will influence ecosystem goods and services depends on looking at biodiversity as a dynamic variable.
BiodiversityWhat does “Diversity” mean? Diversity = Variety
Why protect biodiversity ?MORAL right to exist, stewardship (heritage), unnecessary waste immoralECONOMIC valuable resources now and in the futureECOLOGICAL maintain local to global ecosystem healthLEGAL 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 systemwhere… 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 LifeSeeds + Soil + Nutrition + Water + Sun = FoodNatural 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 isessentially irreversibleEach 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 EcosystemAssessment : five main causes ofbiodiversity 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 ofmodern 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
Modern humans (Homo sapiens) appear about 2 seconds before midnight Recorded human history begins Age of 1/4 second mammals Age of reptiles before midnight midnight Insects and amphibians invade the land Origin of life (3.6–3.8 billion years ago)Plants invadethe land First fossil record of animals Plants begin invading land noon Evolution and expansion of life
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 tremendousbiological diversityThis “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 constituteThis 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
What is biodiversity? The spectrum of life on earth, in terms of variation in genes, populations, species, ecosystems, interactions among them.
Biological DiversityGenetic diversity – the genetic variationamong individuals in a speciesSpecies diversity – the number of differentspecies in a given areaEcosystem (Habitat) diversity – the varietyof interactions among organisms in acommunity (or the variety of ecosystems onEarth)
Biodiversity, the variety of life more interactions COMMUNITY POPULATION INDIVIDUAL GENOME CHROMOSOME GENE ENZYME more biological units
Levels of genetic organization Gene Text sequence Chromosome Chapter Genome Gene pool
Genetic diversity Variation within genes alleles & haplotypes Variation within individuals individual heterozygosity Variation within populations allele frequencies, average heterozygosity, average number of polymorphic alleles and loci. Variation among populations differentiation and genetic distance (pairwise and average)
Species diversityIt represents the different types of plants,animals and other life forms within a region.It is a dynamic property and changes overspace and time.The number of species and their relativeabundances depend on the size andgeographic area of the ecosystem.Species diversity is an indicator of thebiological richness/stress of an ecosystem.
Ecosystem diversityIt is the variety of differenthabitats/ecosystems in a particular area( e.g.. wetland, woodland, grassland).The ecosystems of the world are maintainedby their biodiversity.Every ecosystem can be characterized by itsown species composition.The ecosystems differ in features such asphysical structure, temperature, wateravailability 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 CharacteristicsMajor vegetation types and developmental stages.Rare and unique habitats.Species richness, diversity, distribution.Narrow endemic, geographically restricted, or rarespecies.Spatial structure of populations.Invasives.Keystone species or ecological engineers.Landforms adjacent to stream channels.Wetlands.
Structure CharacteristicsProportion and distribution of vegetation types andsuccessional 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 CharacteristicsFire, 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.
How many different species arethere? 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.
1.Scales of diversity a d a ba Alpha – number of species a in a given plot or area b b c a a a c b c
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 ).
Types of biodiversity measuresWhat 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. Simpsons 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)/ theShannon 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 healthof the earth and its people.It provides us with food andmedicine and contributes to oureconomy.It tells us a lot about the health ofthe biosphere.The greater the variety of species,the healthier the biosphere .
Why is biodiversity important? Regulation of climate and biogeochemical cycles, Hydrological functions, Soil protection, Crop pollination, Pest control, Recreation and ecotourism Ecological resilience Wildlife 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? Oxygen Food Clean Water Medicine Aesthetics Ideas
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.
Earths 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 planets 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
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 ExtinctSpecies Endangered species are in imminent danger of extinction throughout all or part of their range.
Characteristics of EndangeredSpeciesEndangered species have one or moreof these characteristics that makethem vulnerable to extinction : limited natural range low reproductive success specialized feeding requirements large territory requirement
Extinctions can be causedby: ·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,
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 iscaused by human activities. Anywhere that humanstransformations cut up continuous habitat.
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 nativeOther 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.
Biodiversity affects human well-being Human Global activities changes Ecosystem services Biodiversity Ecosystem processes
Links between biodiversity, climatechange and Human well-being
Links between biodiversity,climate change and ecosystemservices
Consumptive Consumptive value valueAestheticAesthetic Productive Productive value value value value Biodiversity Biodiversity Value Value Ethical Ethical Social Social value value value value
Values of biodiversity Values of biodiversityEcological Economic Cultural values values 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 valuesAll living creatures are supported by theinteractions among organisms andecosystems.Loss of biodiversity makes ecosystemsless stable, more vulnerable to extremeevents, 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 valuesMost people feel connected to nature, often forreasons hard to explain.Some feel a strong spiritual bond that may berooted in our common biological ancestory.Others are inspired by its beauty.Human cultures around the world profoundlyreflect our visceral attachment to the natural world.Thus cultural diversity is linked to Earth’s biodiversity.
New ways of thinkingEcosystem Services: the benefits peopleobtain from ecosystemsProvisioning Regulating CulturalGoods produced or Non-material benefits Benefits obtained from provided by from ecosystems regulation of ecosystems ecosystem processes • spiritual • food • climate regulation • recreational • fresh water • aesthetic • disease regulation • fuel wood • inspirational• genetic resources • flood regulation • educational Supporting Services necessary for production of other ecosystem services • Soil formation • Nutrient cycling • Primary production
Many human activities disrupt, impair, orreengineer ecosystems every dayincluding: 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, andHuman 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://news.nationalgeographic.com/news/ http://www.oceansatlas.org/ http://library.thinkquest.org / Over-harvesthttp://www.ourworldfoundation.org.uk/polar.jpg Pollution Climatic change Species invasions Loss of biodiversity Molles 2007 Land use change - type - intensity Global changes
ADVERSE EFFECTS ONECOSYSTEMS 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)
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.
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 ConservationIn-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 ConservationIn 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 ginger11 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 LankaWestern 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.
How do we restore ecologicalbalance 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.
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 islike harmony with a friend;you cannot cherish hisright hand and chop off hisleft. The land is oneorganism. Its partcompete with each otherand co-operate with eachother. To keep every cogand wheel is the firstprecaution of intelligentthinking”– Aldo Leopold
We remember wedepend on eachother, live and let live.