Outline of Last LectureOutline of Current LectureEcology StabilitySuccessionSpecies DiversityDiversity ImportanceReviewBio Sci 150 1st editionLecture 21 Outline of Last Lecture 1. Community Ecologya. Species Interationi. Commensalism1. Nichesii. Consumption iii. Parasitismiv. MutualismOutline of Current Lecture 1. Ecology Stabilitya. Successionb. Species Diversityi. Diversity ImportanceCurrent LectureKey TermsSuccession – the recovery and development of communities after a disturbance occurs.Primary succession - starts from bare rockSecondary succession - starts from soilProductivity – grams of biomass produced per unit of timeResistance – how much is a community affected by disturbance?Resilience – how quickly does a community recover after disturbance?Ecology StabilityHow predictable are communities?- Gleason: not predictable or stable- Clements: predictable series of stages culminating in climax communities- Identical Communities Do Not Develop in Identical HabitatsSuccessionWhat happens after disturbance?Succession is the recovery and development of communities after a disturbance occurs.These notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.- Primary succession - starts from bare rock- Secondary succession - starts from soil- A sequence of communities develops as succession proceedso Succession is influenced by: 1) particular species involved 2) how species interact 3) local environmental conditions Species DiversityWhy are some communities more diverse than others?Species diversity declines as latitude increases.1. Higher productivity in tropics promotes higher diversitya. Productivity: grams of biomass produced per unit of time2. Higher physical habitat complexity in tropics a. does not explain greater tree diversity in tropics 3. Less disturbance in the tropics a. ..but canopy gaps occur as often in tropics as temperate forestsb. or an intermediate level of disturbance?Diversity ImportanceProductivity: total biomass per unit time Resistance: how much is a community affected by disturbance?Resilience: how quickly does a community recover after disturbance?Diversity promotes Productivity- Species-Rich Communities Resist DisturbanceReview- Productivity: total biomass per unit time - Communities are often not stable and predictable - Hypotheses for greater diversity in the tropics- Resistance &
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