IE 116 1st edition Lecture 24 Outline of Last Lecture Coca and CocaineI. Biologya. InfoII. History and Traditiona. South Americab. Past usagec. Trepanationd. QuinoaIII. Componentsa. AlkaloidsIV. Early Proponents of Cocainea. Sigmund Freudb. Marianic. Coca-Colad. 19th CenturyV. Current uses of Cocaa. Traditionb. Western MedicineVI. Policya. Evo MoralesOutline of Current Lecture Invasive species and weedsTerms a. Weedsb. Noxious Weedsc. Exoticd. InvasiveConceptsa. Steps to exotic invasionb. From exotic to invasiveHuman involvementa. Transportationb. EstablishmentWhat makes a species invasive?a. Species traitsb. Enemy Release Hypothesisc. Ecosystem ModificationThese 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.Impacts of invasive speciesa. Competitionb. Alter Ecosystemc. EconomicsManagement Effortsa. Chemicalb. Mechanicalc. Biologicald. CulturalDebate a. Goodb. BadCurrent LectureI. Terms a. Weeds- Any species growing in an area that people don’t want it to grow. (Subjective)o Dandelions in a lawn, tulips in food garden, or Canada thistle in wheat fieldb. Noxious weeds- Government classification (county, state, federal) for undesirable plant speciesc. Exotic- Non-native, non-indigenous, found in an area where they don’t naturally comed. Invasive- Causing negative impacts on the ecosystem because of population size.o Charles Elton :1958 Started sub-discipline of invasion ecology Stressed negative impacts Research and publications on invasive species skyrocketedII. Conceptsa) Steps to exotic invasion1. Transportation: Species is moved from original habitat to new one.2. Establishment: Made it through seasons and reproduces in new habitat3. Naturalization: New population is self-sustaining4. Invasion: New populations spread and begin negatively affecting the ecosystem.b) From exotic to invasive- Many barriers, water, mountains, etc.- Low initial numbers- Not adapted to new location- Tens rule: only 10% of transported species to a location will become established, only 10% will be naturalized, and only 10% of naturalized species become invasive.III. Human Involvementa. Transportation- It’s hard for species to move.- Usually intentionally or unintentionally brought to new areas.b. Establishment- In introduced range, unintentionally and intentionally spread, through seeds in socks or liking of color and spreading.IV. What makes a species invasive?a. Species Traitso Grow quicklyo Produce many seedso Disperse quicklyo Reproduce vegetativelyo Tolerant to diverse conditionso Utilize unoccupied nicheExamples- Rose (Noninvasive)o Slow growingo Few seeds- Dandelions (Invasive)o Grow very fasto Produce many seedso Wind dispersed- Multiflora Rose (Invasive but different traits)b. Enemy release hypothesis- A species loses its natural herbivores and diseases, so it can invest more energy into competition and reproduction.c. Ecosystem modification- Invasion Feedback loopso Cheatgrass – Increases fire frequency- Human-induced changeso Damming rivers, changes flood patterns, helps Tamarisk flourishV. Invasive impactsa. Competition- With crops and grazing (Prickly Lettuce or Leafy Spurge)- Reduces native plant diversityo In turn, reduce abundance native species (plants and animals)b. Alter Ecosystem- Change fire regime (Cheatgrass – the terrible seeds that suck your life through your socks)- Alter water chemistry (Purple Lustrife)- Changes flow of rivers (Tamarisk)c. Economic- Reduction in recreational value of natural landscapesVI. Management effortsa. Chemicals: Use of herbicides to kill plants- Pro: Inexpensive, effective- Con: Dangerous to applicator and environmentb. Mechanical: Physically removing plants- Pro: no harmful chemicals- Con: Expensive and not idealc. Biological: Use other organisms to damage/kill plant- Pro: Specific, minimal follow-up management- Con: Irreversible, risk new invasived. Cultural: use grazing or cover plants to reduce spread- Pro: inexpensive, safe- Con: not often effectiveVII. People Debatea. Good- Mark Davis- Chris Thomas- Mark Sagoffb. Bad- Daniel Simberloff- Petyr Pysek- Tim