The distribution of diversity along latitudinal and elevation gradients, and the coupling of this phenomenon with climate, is a pattern long recognized in ecology. Hypothesizing that climate change may have altered this pattern over time, we investigated whether the aggregate of reported northward shifts of bird ranges in North America is now detectable in community-level indices such as richness and diversity. Here, we report that bird diversity in North America increased and shifted northward between 1966 and 2010.
View Article and Find Full Text PDFThe purpose of this research is to create a baseline model of soil compaction response to trampling and a methodology to model the effects of trampling on soil. Although trampling studies have been conducted in the past, the analysis of military training in part provides a different perspective and approach. The data showed bulk densities remained relatively constant for a time and then began to increase at an increasing rate for several hundred passes and finally leveled and remained at or below 1.
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