SOIL PRODUCTIVITY AND SOIL QUALITY ANALYSIS

A soil productivity and soil quality analysis was designed to objectively monitor a number of different soil characteristics that lead to improved soil productivity and sustainability including detrimental compaction, soil cover, soil disturbance, and large woody debris (LWD). This analysis will attempt to: quantify data collected in the project areas (Jose Basin, Cedar Valley, and Sugar Pine) of the Sierra National Forest in relation to regional soil quality standards and guidelines (S&G's); help decision makers decide on specific treatments and recommendations; insure project areas are in compliance with regional S&G's; attempt to better understand the relationship between soil moisture content and compaction. A Forest Service procedure was used to evaluate soil quality characteristics. A 20 point soil transecting procedure was used to evaluate total soil quality in Jose Basin and Cedar Valley project areas. A line intersect method was used for the Sugar Pine project area. A modified Proctor test was implemented to analyze compaction with varying moisture contents for the encountered soils in the project areas. This soil quality analysis has suggested that more quantitative methods of evaluating soil quality should be used in future studies to produce a higher confidence level and a more precise data set. This analysis will help management understand that more precise data is needed to fully evaluate soil quality at the tree stand level. Some stands in the project areas were approaching guideline thresholds of above 15 percent total detrimental compaction. Stand areas also acquired excess and insufficient LWD quantities. Decision makers may want to alter recommendations and treatments in localized areas to insure that regional soil quality S&G's are met. These soil S&G's are important because they have been deemed as indicators of good soil quality, which leads to increased soil productivity. If soil quality indicators remain within threshold levels then it is expected that the Sierra National Forest can maintain soil productivity and meet land management objectives.