Vegetation Transects

San Pedro Creek Study

Two Methods

• Line-point Intercept– What plant species are found along the

transect and how many? How will the plant species change now that the fence is built?

• Canopy Gap– How much soil is exposed to potential

erosion?

Transects

• Each transect is 30 meters long.

• 3 transects @ the Spring Site

• 4 transects @ the Confluence Site

• Transects are 10 meters apart

• Parallel to each other; Perpendicular to the stream

Line Point Intercept

• Examine each Meter mark along each transect, starting at the 1 meter mark.

• Drop a thin metal rod along the meter tape, imagine the rod extended straight up to the sky, would it touch any vegetation?

• Record each plant that touched the rod starting from the top down.

• Collect a sample of each plant for later identification by Botanist Will Barnes. Label each plant sample with the code used on the data sheet. Place samples in plastic bag.

• Also record the presence of rocks, soil and water.

Canopy Gap

• Starting at the zero mark on the meter tape, look for exposed soil with nothing covering it.

• Any living plant, litter (dead plant material), rocks or animal waste is considered cover.

• Record the distance from zero in centimeters of the start of the gap in the “from” column.

• Record the distance from zero in centimeters when the gap stops in the “to” column. Stop when you get to any object wider than 2cm covers the soil.

• Only record gaps 20 cm or longer.• Any plant, litter or rock smaller than 2 cm does not count

as cover. Any object larger than 2 cm will “stop” the gap.

Riparian Vegetation• Vegetation growing along the banks of a river

or stream, such as willow and cotton woods. • Holds soils, prevents erosion, can help filter

run off, helps reduce turbidity• Shades the stream keeping it cooler. Colder

streams can hold more Dissolved Oxygen. Some species of fish need cold water and high levels of dissolved oxygen to live and breathe.

• Can provide habitat to many animals year-round and for migratory animals like birds and butterflies.

• Builds up the soils along the bank that can act as a sponge and provide water for stream flow during dry periods.