Laserfiche WebLink
Field Sampling <br />Vegetation Cover and Species Composition <br />Vegetation cover was estimated by the use of the point-intercept method. A laser (ten) <br />point frame was used to minimize instrument error and maximize precision and observer <br />accuracy. Cover transects were 25 meters in length, with ten sample data points collected <br />at 5.0 meter intervals along the transect on both sides of the transect centerline, for a total <br />of 100 points per transect. Transect orientation was randomly determined by random <br />numbers generated (between ]and 360). In no event were transects allowed to extend <br />within ten feet of revegetated azea boundaries, to minimize impacts from "edge effect." <br />For statistical purposes, each cover transect served as a sample unit. Data points recorded <br />the first vertical "hit" on vegetation (as determined by the laser point frame), soil (bare <br />ground), rock, or litter. The data were summarized by computing mean cover, relative <br />cover (percent of total vegetation cover attributed to each species), and species <br />composition. Species composition information was computed from vegetation cover data <br />using a ratio of individual species cover to total vegetation. <br />Production <br />Biomass production data were obtained using a harvest method. All of the current years <br />growth included within cone-half squaze meter quadrat was clipped at both ends of each <br />transect. Full shrubs, succulents, noxious weeds, and cushion plants were not clipped. <br />Clipped biomass was placed in paper bags, and dried in Colorado State University's <br />Rangeland Ecosystem Science Laboratory forced air ovens for 24 hours at 105°C. <br />Samples were weighed on an appropriate scale to the nearest tenth of a gram and reported <br />in g/mz and lbs/acre. Clipped samples weighing less than 0.10 grams were reported as <br />trace samples. Average paper bag weight was subtracted from weighted samples. <br />Sbrub Density <br />Shrub density data were collected using a belt transect approach. All shrubs occurring <br />within one meter on either side of the 25 meter transect line (used for collecting cover <br />data) were counted on the basis of species. Stem count will be recorded by species and <br />reported as stems per acre. <br />Sample Numbers/Sample Adequacy <br />Sample adequacy calculations were made for vegetative cover of the sampled reclaimed <br />area. The following formula, accepted by the CDMG, was used for these calculations: <br />z z <br />Amin - t S <br />(d Xbar)z <br />3 <br />