Outline. Overview of Vegetation Methods. Basic Field Skills. Basic Field Skills. Basic Field Equipment. Basic Field Skills

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1 Overview of Vegetation Methods Outline Basic field skills Basic field equipment Vegetation sampling methods Ecological Monitoring and Analysis (REM 357) Spring Mtns., NV Basic Field Skills What am I doing? Keep objectives in mind Get feedback from others on plan Constantly re-evaluate your plan Basic Field Skills How am I doing it? Document everything (field notebook) Don t change protocol mid-stream Be consistent and strive for accuracy and precision Basic Field Skills What do I keep in mind? Be prepared for adverse weather conditions Be prepared for emergencies Adhere to safety Basic Field Equipment Herrick et al. 2009; Vol. II p. 34 1

2 Basic Field Equipment Vegetation Sampling Methods 1. Site Description 2. Photos 3. Line-point Intercept 4. Gap Intercept 5. Belt Transect 6. Quadrat/Daubenmire 7. Robel Pole Traditional Key Attributes Herrick et al. 2009; Vol.II p Site Description Vegetation based Frequency presence/absence of species Cover - % ground covered by vegetation (or rock, soil, crust, litter) Density - # individuals per unit area -biomass Structure arrangement in 3-dimensional space Composition proportion of various plant species Sampling Vegetation Attributes 1999 Photo Points Photo Points Herrick et al. 2009; Vol. I p. 6 2

3 Photo Plots Elzinga 1998 Line-point Intercept Quantifies soil, vegetation, litter, rock and crust cover Predetermined number of points along transect Drop pin flag and record all categories that touch pin flag at canopy level and at base Herrick et al. 2009; Vol. I p. 9 Line-point Intercept Line-point Intercept Herrick et al. 2009; Vol. I p. 11 Herrick et al. 2009; Vol. I p. 15 Measures gaps between plants Gaps in canopy indicate potential wind erosion and Gap Intercept weed invasion Gaps in bases indicate runoff and water erosion Determine minimum gap size (often 20cm); plant canopy Herrick et al. 2009; Vol. I p. 16 > 3cm) Include annuals? Herrick et al. 2009; Vol. I p. 18 Gap Intercept 3

4 Gap Intercept Gap Intercept Herrick et al. 2009; Vol. I p. 18 Belt Transects Belt Transect transect Use to measure invasive plants or woody species Record in predetermined size classes Determine belt width Record all plants encountered in belt Herrick et al. 2009; Vol. I p. 30 Used to measure: Cover Frequency Density Composition transect quadrat Boundary Decisions 1. Two adjacent sides 2. Alternate plants 3. >50% of plant in Apply decisions consistently!!! quadrat quadrat 4

5 1. What happens if you count all plants that touch the boundary? 2. What happens if you count only plants entirely within boundary? Cover classes Direct Method 1.Clip, dry and weigh Dry C for hours % dry matter = dry wt./fresh wt. * 100 Indirect Methods 1. Comparative Yield Select five plots that cover range of biomass Rank all plots relative to five reference plots Harvest reference plots 2. Dry Weight Rank Determine three most abundant species in a plot Rank them 1, 2, or 3 according to dry weight biomass Multiply by: 1 x 0.70, 2 x 0.20, 3 x 0.10 Add up weighted values for each species Gives relative biomass values for each species but Indirect Methods 1. Weight Estimate Define unit of vegetation Estimate wet weight and count the # of units Correct to dry weight after drying 2. Double Sampling Weight Estimate corrected for observer bias Clip a few plots and adjust estimates 3. Plant Dimensions Measure canopy widths and plant height Harvest representative size classes and establish a regression to estimate biomass Robel Pole Provides information on: visual obstruction habitat structure biomass 5

6 Robel Pole Steps: 1. Randomly select five positions along transect 2. Place pole at each position 3. Stand 5 feet from pole (Maintain observer height) 4. Count # of bands covered by vegetation ( 25% band cover) 6