Presentation on theme: "ES: Community Ecology, Population Ecology, and Sustainability"— Presentation transcript:
1 ES: Community Ecology, Population Ecology, and Sustainability Chapter 6
2 KEY IDEAS What determines the number of species in a community? How classify according to roles in community?How do species interact?Communities respond to environmental changes?How do reproductive patterns differ in species? Human Impact?How do Niches Change?Sustainability?Natural Capital?
4 NICHE and ADAPTATIONS (4.3) & ( 6.3) A Niche is an organisms role in the ecosystem. It affects it and others survival and reproductive Fitness(reproduction)No two organisms occupy the same nicheHabitat: Where it lives
5 Niche: Fundamental and Realized Realized the actual range available due to competitionFundamentalFull potential range that can theoretically usedChthamalus : fundamentally couldlive in many zones. Balanus moveshim out.
6 NICHE Fundamental niche Realized Niche Describes the potential a species has to be completely successful in using its resources to the fullest extent without competition,predation, or pressure from limiting factors.Describes what a species is actually going to do in terms of using its resources due to pressures from limiting factor s ,predation, or competition
7 Exclusion of an organisms niche Competitive Exclusion or interspecific exclusionIntraspecific ExclusionCompetition between two species forms exclusion of each other . They Competitively exclude one another out of a niche .One of the competitors always overcomes the other.New niche may form or evolutionary shift or extinctionWhen the same species exclude each other it is Intraspecific Exclusion.Niches Overlap
9 When the same species exclude each other it is Intraspecific Exclusion The woodpecker Males characteristically forage on small trees or on small branches of large treesfemales typically forage on the trunks and larger limbs of large trees.The niches overlap, but the slight distinction limits competition between the sexesSo long as there are enough resources species can share them.
10 Can lead to adaptations or radiation of the species
11 Radiation of the Species: adaptations form from competition creating speciation – new species
12 Resource Partitioning reduces or avoids competition Specialized traits evolve that allows them to share resources at differentTimes -temporalWays- Ways they get foodplaces - different areas of same resourceOne tree many resources
13 Speciation:Formation of a species through competition, limiting factors, and adaptations
14 Resource partitioning summary: forms adaptations that cause specialization and new niches
15 Limiting Factors ?DDLF – DDIF? Density Dependent Limiting factors (DDLF)Density Independent Limiting factors(DILF)Limiting factors that are intensified by the density of populationsAre typically bioitc factorsCompetitionBacterial diseaseSymbiosis-species relationshipsLimiting factors that are NOT intensified by population numbersAre typically abiotic factorsClimateNatural disastersViral disease
16 6.1 Community Structure and Species Diversity Physical Appearance – Sizes, stratification and distribution of species (pg 110)Physical Appearance lends to species richness and evenness as physical appearance changes
17 Community Structure is Zoned Community Structure is Zoned. Zones are Wide and Varied due to many factorsAquatic Zones affected by temperature, amount of light, salinity,pressure,
18 Some other Factors cause these variances: Sunnier, warmer, drier, lighter, darker,moister, acidic, salinity,biomass abundant…
19 Zoned Life is Patchy…. (directly from your book!) Community structure also varies around its edges where transitions of communitiestake place.
20 Human Impact: Habitat Fragmentation Increases forest edge or buffers: Makes species more vulnerable to stresses like predators, fire, and creates barriers where species cannot colonize and finding food.
21 Species Diversity and Niche Structure Species Richness (number of species)Species Evenness (number of individuals within species) = Species DiversityAllows community a to differ from b to differ from c………Typically a community is either rich or even but not both!
22 Species Diversity Types Species Richness The number of species in an areas of each species present. This is rrsityHow rich are the species in your area?Species Evenness : how many of each species exists in that areanumber of members How even is the diversity?IF: Species A = 56 membersSpecies B = 55 membersSpecies C = 52Then: species evenness is good but diversity is low!Rainforest, coral reef , deep sea, large tropical lakes have high species diversity but low species evenness(few members in each)
23 DIVERSITY CREATES NICHE STRUCTURE Highest in tropics and declines as move North and south from equator
25 Are Complex Communities more sustainable than Simple ones? Typically: Net Primary productivity indicates ecosystem is more resilient with species diversity of (complex) However, not conclusive, and still a hot environmental topic. Some believe simple communities have just enough diversity to survive.Agree: All communities need producers and decomposers .which producers and which are essential is the question.
27 6.2 Species Types Native:Normally live and thrives in area Has competitors andNatural predatorsNon-Native,Invasive, Alien Have Migrated or been deliberately or accidentally transferred into an area Some have no effect: corn, chickens
29 Indicator Species Biological smoke alarms Fish, birds, amphibians, butterfliesIndicate ecosystem health: pH, Habitat fragmentation, dissolved oxygen in water communities, pollution, reduction in stratospheric ozone, climate change, over hunting…
30 Amphibians as an Indicator Species Habitat loss-defragmentationProlonged DraughtPollution – pesticidesUV RadiationParasitesOverhuntingViral/Fungal diseasesNon-native predators/competitors
31 WHY CARE? 1st – environmental health deterioration 2nd – Amphibians eat more pests and feed many others3rd – They are genetic storehouse of pharmaceuticalsPainkillers, antibiotics, burn treatment(biopharming)
32 Keystone SpeciesA wedge shaped stone placed in an archway supporting the entire archIF REMOVED: DRAMATIC !!!!Ecological Services go out all over
33 Keystone SpeciesHave a huge effect on the species richness and evenness of an ecosystem.A keystone species disappears can lead to population crashes and extinction.
34 Keystone Niche Pollination Regulation/control population Remove, Bury, Recycle (dung it anyway!)Biopharming
35 Foundation Species: Create and enhance habitat in ways that benefit others Trimming TreesRolling over rocksTearing trees out by rootsPlanting
36 6.3 Species InteractionsKey Concept: Increase ability to survive through Competition and Symbiotic Relationships
37 Competition Interspecific Competition Abundant Resources personify fundamental nicheNon abundant causes a more realized nicheHumans deprive species of resources causing more realized niches occupationInterspecificCompetition
38 Can we Reduce or Avoid Competition? Competition allows for 1.Adaptations through Natural Selection2.Predator/Prey Relationship Prey on the least fit3.Keeps populations in check not to exceed resources
39 How do predators increase their chances of catching prey? Lie in waitPersueCamoflage
40 Can Prey Defend Themselves? EscapePretective shellsCamoflageMimicryChemicals
41 Parasites Sponge Off Each Other Parasite (sponger)Host (spongee)
42 Other symbiotic relationships Mutualistic:Commensalistic:ParasiticBoth benefit ++One benefits other is neither harmed or benefits +0One benefits the other is harmed +-
43 6.4 Ecological Succession Change of Producers mass Over TimeTerrestrial Succession
45 SuccessionPRIMARYGradual establishment of biotic communities on newly exposed rockNo soil, No bottom sedimentReceding ice bergsNew Lava FlowsSECONDARYOn existing soil, or bottom sedimentReestablishment of any Cleared area due toFires, tornados, tsunamis, human impact
48 From Pioneer Species to Intermediate Species, to a Climax Community Primary: initial, does not need much soil or water Intermediate species: need some soil, water, sun Climax community: needs more soil and other factors
49 Can we Predict Succession? Not Always An ever changing mosaic of vegetation patchesOn going struggle by species for resourcesClimax Community: Mature community for that climate
50 6.5 Population Dynamics and Carrying Capacity Enter: Births, immigration, and decrease in deathsExit: Death, emigration
52 Overshoot of Carrying Capacity Occurs when births are greater than deathsHumans not exemptThen causes a ‘dieback’ or ‘crash’Polynesians on Easter Island
53 Carrying Capacity is ecosystems maximum ability to support populations Carrying Capacity is ecosystems maximum ability to support populations. Directly related to producer biomass and climate
54 Exponential vs. Logistical Growth Curves Lag Phase—First portion of the curve; slow population growth.Exponential Growth Phase—More organisms reproducing causing accelerated growth; continues as long as birth rate exceeds death rate.Stable Equilibrium Phase—Death rate and birth rate equilibrate; population stops growing; achieved in logistical growth curves
56 Reproductive Patterns R and K Strategies Some species have few offspring and take care of them until they care for themselvesK Selected Species( K = competitor)Some have many and care-lessR-selected species(R means Rapid)
57 Reproductive Strategies and Population Fluctuations Not all species reach a stable carrying capacity.Species can be broadly lumped into two categories:K- strategists- competitor species; they do well in competitive situations where population size is close to or at carrying capacity; logistical growthR-strategists- have a high intrinsic rate (r) of increase; exponential “boom & bust” cycles of growth
58 Reproductive Strategies Which one has a greater Range of Tolerance? K-selected:mature slowlyhave few offspring at a timemost endangered species are K-selectedpopulation stabilizes near carrying capacitymaintain numbers in stable ecosystemsDo well in competitive conditionsSpecialist NicheLate Succession dwellersHigh ability to competeLivestockMammalsr-selected:mature rapidlyhave many offspring - tend to overproduce Die before reach maturity population not regulated by density opportunistic -- invade new areasGeneralist NicheEarly Succession dwellerslow ability to competeopportunistsCropsAlgaelBacteriaDepends on the available habitat determines success!
59 6.6 Human Impact on Ecosystems Where Natural Systems would allowre-growth, reuse,recycling, and be renewable…Man doesn’t and is less forgiving ,simplifying biodiversity, Using up non-renewable energy, producing much waste, wastes rather than recyclesand uses, destroys, or degrades Net ProductivityIe: (doesn’t share with others well)
60 Principles of Sustainability Follow Nature - Four WaysNutrient Cycling -Renewable Resources Especially Energy and wasteSolar EnergyUse Biodiversity to maintain itself and adaptControl population size and resource use