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KETAHANAN EKO- SISTEM Biodiversitas

KETAHANAN EKO- SISTEM Biodiversitas. smno.psdl-ppsub.2013. ECOSYSTEM BIODIVERSITY. BIODIVERSITAS. Biodiversity = the amount of biological or living diversity per unit area. It includes the concepts of species diversity, genetic diversity and habitat diversity

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KETAHANAN EKO- SISTEM Biodiversitas

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  1. KETAHANAN EKO- SISTEM Biodiversitas smno.psdl-ppsub.2013

  2. ECOSYSTEM BIODIVERSITY

  3. BIODIVERSITAS • Biodiversity = the amount of biological or living diversity per unit area. It includes the concepts of species diversity, genetic diversity and habitat diversity • Genetic diversity = the range of genetic material present in a gene pool or population of a species • Species diversity = variety among species per unit area. Includes both the number of species present and their abundance. • Habitat diversity = The range of different habitats or number of ecological niches per unit area in an ecosystem, community or biome. Conservation of habitat diversity usually leads to conservation of species and genetic diversity Diunduhdari: plattscience.wikispaces.com/file/.../18.+Biodiversity+in+Ecosystems.p...... 19/12/2012

  4. BIODIVERSITAS: SPESIES & PROSES • Is key to the overall function of earth • In general Diversity = Stability • Biodiversity is • Nature’s insurance policy against change • The source of all natural capital for human use • The way chemical materials are cycled and purified • The end result of millions of years of evolution and irreplaceable Diunduhdari: plattscience.wikispaces.com/file/.../18.+Biodiversity+in+Ecosystems.p...... 19/12/2012

  5. BIODIVERSITAS • Richness: The number of species per sample is a measure of richness.  The more species present in a sample, the “richer” the sample. • Evenness: A measure of the relative abundance of the different species making up the richness of an area. Diunduhdari: plattscience.wikispaces.com/file/.../18.+Biodiversity+in+Ecosystems.p...... 19/12/2012

  6. Quantifiying this Diversity – Simpson’s Index D = N (N – 1) ∑ n (n – 1) • Where D = diversity index N = total # of organisms of all species n = # of individuals of particular species Diunduhdari: plattscience.wikispaces.com/file/.../18.+Biodiversity+in+Ecosystems.p...... 19/12/2012

  7. Quantifiying this Diversity – Simpson’s Index • High values of “D” suggests a stable and ancient site • A low value of “D” could suggest pollution, recent colonization, or agricultural management • Index normally used in studies of vegetation but can be applied to comparisons of diversity of any species Diunduhdari: plattscience.wikispaces.com/file/.../18.+Biodiversity+in+Ecosystems.p...... 19/12/2012

  8. How does diversity exist? • Natural Selection = survival of the fittest • Fitness = a measure of reproductive success • If all individuals are variable • And populations produce large numbers of offspring without increase in population size • And resources are limited • And traits are heritable • Then those individuals who are best adapted to the environment will survive and pass on their genes • Gradually the gene frequency in the population will represent more of these “fit” individuals Diunduhdari: plattscience.wikispaces.com/file/.../18.+Biodiversity+in+Ecosystems.p...... 19/12/2012

  9. SELEKSI ALAMIAH • Environmental Pressures select for some genotypes over others • Alleles resulting in a beneficial trait will become more common • Heritable traits that increase survival chances are called adaptations • There are many niches or habitats and roles available in the environment • As populations adapt they fill new niches and over time may develop into new species Diunduhdari: plattscience.wikispaces.com/file/.../18.+Biodiversity+in+Ecosystems.p...... 19/12/2012

  10. Diunduhdari: plattscience.wikispaces.com/file/.../18.+Biodiversity+in+Ecosystems.p...... 19/12/2012

  11. Speciation • Certain circumstances lead to the production of new species through natural selection • Most common mechanism has 2 phases  geographic followed by reproductive isolation 1. Geographic isolation  groups of a population of the same species are isolated for long periods • A group may migrate in search of food to an area with different environmental conditions • Populations may be separated by a physical barrier (mountain range, river, road) • Catastrophic change by volcano eruption or earthquake • A few individuals carried away by wind or water to new area Diunduhdari: plattscience.wikispaces.com/file/.../18.+Biodiversity+in+Ecosystems.p...... 19/12/2012

  12. Speciation 2 • Reproductive Isolation  mutation and natural selection operate independently on the 2 populations to change allele frequencies = divergence • If divergence continues long enough genetic differences may prohibit (1) interbreeding between populations and/or (2) production of viable, fertile offspring • One species has become 2 through divergent evolution • For most species this would take millions of years • Difficult to document & prove this process Diunduhdari: plattscience.wikispaces.com/file/.../18.+Biodiversity+in+Ecosystems.p...... 19/12/2012

  13. Northern population Adapted to cold through heavier fur, short ears, short legs, short nose. White fur matches snow for camouflage. Arctic Fox Spreads northward and southward and separates Different environmental conditions lead to different selective pressures and evolution into two different species. Early fox population Southern population Adapted to heat through lightweight fur and long ears, legs, and nose, which give off more heat. Gray Fox Diunduhdari: plattscience.wikispaces.com/file/.../18.+Biodiversity+in+Ecosystems.p...... 19/12/2012

  14. Consequences of Plate Activity • Speciation processes rely on physical separation of organisms • Plate techtonics • can lead to separation of gene pools – mountain ranges form, faults separating land masses • Can link species and land areas e.g. land bridges Diunduhdari: plattscience.wikispaces.com/file/.../18.+Biodiversity+in+Ecosystems.p...... 19/12/2012

  15. Consequences of Plate Activity II • Plate techtonics generates new habitats • Island chains over hotspots – Hawaii • Mountain habitats – Himalayan mountains – also associated effects on surrounding areas • Hydrothermal vent communities • Changes climate on land masses – continents drift into new climate zones  e.g. antarctica was once covered by tropical rainforest now barren polar ice fields Diunduhdari: plattscience.wikispaces.com/file/.../18.+Biodiversity+in+Ecosystems.p...... 19/12/2012

  16. 1. Succession effects Diversity • Succession – gradual establishment or reestablishment of ecosystems over time • Pioneer species  Climax species • Low diversity at first, few species can tolerate harsh conditions (r selected species) • Most diverse in middle of succession, slower growing species start to fill in • Low diversity at the end, climax species often strongest competitors (K selected species) • Diversity is a function of disturbance  intermediate disturbance hypothesis Diunduhdari: plattscience.wikispaces.com/file/.../18.+Biodiversity+in+Ecosystems.p...... 19/12/2012

  17. Lichens and mosses Balsam fir, paper birch, and white spruce climax community Exposed rocks Heath mat Jack pine, black spruce, and aspen Small herbs and shrubs Time Diunduhdari: plattscience.wikispaces.com/file/.../18.+Biodiversity+in+Ecosystems.p...... 19/12/2012

  18. Species diversity 0 100 Percentage disturbance Diunduhdari: plattscience.wikispaces.com/file/.../18.+Biodiversity+in+Ecosystems.p...... 19/12/2012

  19. 2. Habitat diversity influences species & genetic diversity • More complex areas (more diverse habitats) often have higher species & genetic diversity • Ex. Tropical rainforest & Coral reef • In both cases, high degree of structural / spatial complexity • Promotes coexistence by niche partitioning & diversification Diunduhdari: plattscience.wikispaces.com/file/.../18.+Biodiversity+in+Ecosystems.p...... 19/12/2012

  20. Slaty-tailed trogon Slaty-tailed trogon Harpy eagle Ocelot Blue and gold macaw Producer to primary consumer Primary to secondary consumer Squirrel monkeys Climbing monstera palm Secondary to higher-level consumer Katydid Green tree snake Tree frog All producers and consumers to decomposers Ants Bromeliad Fungi Diunduhdari: plattscience.wikispaces.com/file/.../18.+Biodiversity+in+Ecosystems.p...... 19/12/2012 Bacteria

  21. Understory Understory Ground layer Ground layer 45 Emergent layer Harpy eagle 40 35 Toco toucan Canopy 30 25 20 Height (meters) Wooly opossum 15 10 Shrub layer Brazilian tapir 5 Black-crowned antpitta 0 Diunduhdari: plattscience.wikispaces.com/file/.../18.+Biodiversity+in+Ecosystems.p...... 19/12/2012

  22. Complex ecosystems with a variety of nutrient & energy pathways provides stability • Energy is key to the function of all ecosystems • Biogeochemical cycles recycle necessary materials through system • More pathways for energy & matter = more stable • Insurance against natural or human changes Diunduhdari: plattscience.wikispaces.com/file/.../18.+Biodiversity+in+Ecosystems.p...... 19/12/2012

  23. AktivitasManusia • Modify succession by adding disturbance • Logging, Grazing, Burning – all prevent natural successional processes • Fragmenting habitats by development • Isolate populations  more likely to get diseases, succumb to local disturbances • We simplify ecosystems  tall grass prairie converted to wheat farms  more vulnerable Diunduhdari: plattscience.wikispaces.com/file/.../18.+Biodiversity+in+Ecosystems.p...... 19/12/2012

  24. Cleared plots for grazing Highway Cleared plots for agriculture Diunduhdari: plattscience.wikispaces.com/file/.../18.+Biodiversity+in+Ecosystems.p...... 19/12/2012

  25. Any ecosystem’s capacity to survive change may depend on its diversity, resilience, and inertia Diunduhdari: plattscience.wikispaces.com/file/.../18.+Biodiversity+in+Ecosystems.p...... 19/12/2012

  26. Biodiversitas Agroekosistem

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