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Matthew A. Williamson

Cheatgrass (Bromus tectorum) has increased the extent and frequency of fire and negatively affected native plant and animal species across the Intermountain West (USA). However, the strengths of association between cheatgrass occurrence or abundance and fire, livestock grazing, and precipitation are not well understood. We used 14 years of data from 417 sites across 10,000 km(2) in the central Great Basin to assess the effects of the foregoing predictors on cheatgrass occurrence and prevalence (i.e., given occurrence, the proportion of measurements in which the species was detected). We implemented hierarchical Bayesian models and considered covariates for which > 0.90 or < 0.10 of the posterior predictive mass...
This document details our analysis of contemporary usage of available climate information for federal land management decisions. For this analysis, we focus on those decisions where respondents indicated that climate information was relevant to the decision being considered. We then evaluate which of the existing products are used most frequently (and the attributes of the decisions in which they were used). In addition, we consider the motivations for not using climate information despite its suggested relevance.
Abstract (from http://www.ingentaconnect.com/content/saf/jof/2016/00000114/00000002/art00008): Collaborative natural resource management has emerged as a means to increase the transparency of decisionmaking in public lands management and to promote shared learning among stakeholders. We developed a rapid forest assessment (RFA) approach for monitoring the key characteristics of forests that capitalizes on the growing interest for citizen science monitoring and can be implemented at large extents. The methods were designed for use with minimal training, to maximize field efficiency, and to simplify interpretation of the data. We chose our variables based on the common interests and questions of collaborative groups....
Abstract (from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4794763/): Since 2000, the phenology has advanced in some years and at some locations on the Qinghai-Tibetan Plateau, whereas it has been delayed in others. To understand the variations in spring vegetation growth in response to climate, we conducted both regional and experimental studies on the central Qinghai-Tibetan Plateau. We used the normalized difference vegetation index to identify correlations between climate and phenological greening, and found that greening correlated negatively with winter-spring time precipitation, but not with temperature. We used open top chambers to induce warming in an alpine meadow ecosystem from 2012 to 2014. Our results...
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