Laserfiche WebLink
• computer generated random compass deections. In no event were transects allowed to <br />extend within ten feet of the new reference azea boundary to minimize impacts from "edge <br />effect." <br />For statistical purposes, each cover transect (comprising 50 data points) served as a <br />sample unit. Data points recorded the fast vertical "hit" on vegetation (above or below <br />the instrument), cryptogams, bare ground, rock, or litter. Subsequent "hits' on vegetation <br />were also recorded. Cover data were recorded and reported by individual plant species. <br />The first interception was used to calculate total cover values. Additional interceptions <br />were used to calculate relative cover of individual plant species and Gfeforms. The <br />quantitative cover data also provided the basis for analysis of species composition. <br />Herbaceous Production <br />Herbaceous production was estimated by the harvest method. One herbaceous production <br />plot was located and randomly oriented at the beginning of each cover transect. <br />Herbaceous production plots were 0.50 square meters in area. All current year above <br />ground Eve herbaceous plant biomass was clipped within the 0.50 square meter quadrat. <br />Perennial grasses, annual grasses, annual, biennial, and perennial forbs as well as any <br />suffivtescent species were clipped and bagged to represent total herbaceous production. <br />Succulents and woody plants were not sampled. Production material was air dried until <br />weights varied by no more than O.lg. Results are reported as grams per square meter. <br />Woody Plant Density <br />In order to evaluate woody plant density in the reference area, belt transects 2x25 meters <br />in size (50 rrt2) were sampled along the randomly oriented vegetation cover transects. <br />Species Composition <br />Species composition information was derived from quantitative vegetation cover data. <br />Relative cover information provided a basis for evaluation of the importance of each <br />encountered plant species and lifefotm. <br />Sample Numbers/Sample Adequacy <br />For the purposes of this study, total vegetation cover, total herbaceous production, and <br />woody plant density sampling was undertaken to sample adequacy or a maximum of fifty <br />samples in the reference area. A nilnimum of fifteen samples per parameter were taken. <br />Parameters were tested at the 90% confidence level. Calculated minimum sample numbers <br />and standard deviations are reported as an indication of variability of the sampled <br />pazameters. Comparisons between sample mean parameter values assume that the sample <br />mean value accurately represents the population mean in all cases. The following formula <br />• was used for sample adequacy calculations: <br />-3- <br />