lab 2. overview

Lab 2. Overview Instructor collects lab. 1 write ups and

checks pre-labs. in lab notebook Review of Lab Expectations (Exercises,

Pre-Lab, and Attire) Overview of Populations, Plant Structure,

and Quadrat Sampling. In-class plant structure examination Gather plant density data in field Return to lab room. Plant Tagetes patula (French marigolds) Exercise due in Lab 3 discuss. & questions

Population EcologyPopulation = group of individuals of

the same species in a single area (Population) Density = # of individuals

(of the same species) per unit area

Individual, Population, Species Individual (e.g., you, a tree)

Population = individuals of the same species in a single area (e.g., all people in Denver)

Species = the largest cluster of individuals that is genetically isolated from other groups of individuals and maintains its identity (e.g., all people in the world) ≈ “kind”

Use ThisWord

Carefully

Individual & PopulationPopulation

Individual

Species = all the in the world

Plant Structure

Simple vs. Compound Leaves

trifoliatebipinnate

Kinds of Plants (Ecological)Woody Plants =

Produce woody stems (trees & shrubs)

Herbaceous Plants = Do not produce woody stems

-Grasses-Forbs = not grasses

-Rosette growth form-Vining growth form-Erect growth form

RosetteTaraxacumofficinale

ErectMedicagosativa

viningConvolvulusarvensis

Slope

N S

E

W

west-facing slope

east-facing slope

south-facing slope

north-facing slope

• What conditions of sun exposure, heat, and moisture would each slope experience?

Quadrat - Density Sampling

m2

m2

m2

samples =samples =

42

61

80

m2

44

mean = 5.50mean = 1.75

Reminders Before the Field READ the instructions () in the manual Develop hypotheses (two; 1 per species) now. Count the number of individuals of each of

the two species SEPARATELY in each quadrat.

Decide what it means to be “in” a quadrat. Base of plant?

Sample randomly in each area. “0” is still a value. Obtain your unpaired t-test P-value using

the online site linked to the course website.