Wet-lab (Diversity Determinations)

Wet-lab (Diversity Determinations)

Work Group:

Date: Tow depth:

Net:

Mesh:

Tow time:

Number of Individuals

Taxa

Mangrove lagoon Amphipoda

Reef habitat

Mangrove channel

Chaetognatha Cephalopoda Cladocera Cladocera Cumacea Decapoda Foraminifera Gastropoda Hydrozoa Isopoda Ostracoda Polychaeta Pteropoda Sergestidae Siphonophora

Wet-Lab, Continued Data Analysis

Mangrove channel Mangrove lagoon No. of groups No. of individuals Diversity Index

Reef habitat

Note: Do diversity calculations on a separate sheet with the following formula.

H=log N - [1/N ∑ (n i log n i )]

Where:

H = Shannon-Wiener's Diversity Index N = Total number of individuals th n

i =Number of individuals in the i group

Interpretations

1. Which community is the most diverse?

2. Which taxonomic group appeared to be the most

3. Is there a notable trend in the diversity values as we move from one community to another?

Field Activity: Environmental Extremes and Adaptive Strategies in Mangroves

Objective: Participants will examine environmental characteristics along a transect across

a mangrove forest. They will also become familiar with mangrove structural/ anatomical characteristics that confer resistance to the abiotic stress factors present in the mangrove habitat.

Summary: Participants will conduct measurements of salinity, temperature, light intensity, and flooding intensity at three sample sites representing different environmental extremes. They will also record differences in structural and/or anatomical characteristics observed among the three mangrove species and across sites.

Materials: Field

Thermometers (temperature) Quantum irradiance meter (light intensity) Collecting bags Clipboard, data sheets, pencil Pocket knife Centimeter rule Calipers Meter tape Protractor Sample bottles

Lab

Refractometer (salinity) pH meter Leaf area meter Microscopes Hach kits (nitrates and phosphates)

Station 1. Fringe forest Station 2. Interior forest Station 3. Dwarf forest

At each station, you will measure temperature, light levels, water depth, tree height and dbh (diameter at breast height) and collect water samples for measurement of salinity, nutrients, pH, and sulfide. You will also collect leaves, twigs, and roots for examination of morphology and anatomy in the laboratory.

1. Measure:

a) Temperature of air, water, and soil (5 cm depth)

b) Light levels: direct and reflected light (expressed as a percentage of a reference)

c) Water depth at high and low tide

d) Height and dbh of 5 representative trees (of the species dominating the canopy)

2. Collect pore-water with the sipper device provided. Collect a reference seawater sample from the end of the pier. Place collected water in the sample bottles provided and label. Return to lab and measure salinity with the refractometer ,pH with the pH meter, and nitrate and phosphate with the Hach kits. Sulfide will be assessed by a ranking procedure: open the bottle briefly and smell. Rank the odor of the sample as follows: 0 = no detectable odor of sulfide, 1 = weak odor, 2 = strong odor.

3. Select a representative terminal twig on the five trees measured above. Locate the penapical leaf pair and measure their orientation relative to the twig with the protractor. Collect these twigs and place in the plastic bags. Return samples to the lab and measure leaf area, width, and length of all leaves on a twig with the leaf area meter. Compare the color of the leaves collected at this site with that from the other two stations. Note any chlorotic mottling. Cut a thin cross-section of a leaf and mount on a slide. Sketch the cross-section and identify the following layers or structures: cuticle, upper epidermis, hypodermis (if present), palisade and spongy mesophyll, lower epidermis, salt glands (if present), hairs (if present), stomata.

Examine the twigs and observe the leaf scar arrangement Measure the internodal distance