Treesearch

The first step in designing a surface water sampling program is identifying one or more problems or questions that require information on water quality. Common water quality problems include nutrient enrichment (from a variety of causes), effects of atmospheric deposition (acidification, eutrophication, toxicity), and effects of major disturbances such as fire or pest infestations. Once the problems or questions have been clearly defined, a sampling program can be designed that addresses where to sample, what to measure, and when and how to conduct the sampling. The selection of measurement...

Presents recent Missouri forest industry trends; production and receipts of industrial roundwood; and production of saw logs, veneer logs, pulpwood, and other products in 2009. Logging residue generated from timber harvest operations is reported, as well as wood and bark residue generated at primary wood-using mills and disposition of mill residues.

Most mature lodgepole pine (Pinus contorta var. latifolia Engelm. ex Wats.) forests in the central and southern Rocky Mountains originated after stand-replacing wildfires or logging (Brown 1975, Lotan and Perry 1983, Romme 1982). In recent years, mountain pine beetle (Dendroctonus ponderosae Hopkins) outbreaks have created a widespread, synchronous disturbance (i.e., greater than 1.4 million hectares of pine forests in Colorado and southeastern Wyoming since 1996) (USDA 2010) that will shape forest dynamics for the coming century. Compared with the ample knowledge of how lodgepole forests...

Native forests and grasslands worldwide have been converted to developed lands or invaded by exotic species due to human activities. These pressures are predicted to increase with population growth and climatic stress in coming decades, escalating concerns for the viability of native species and communities that are affected. Ecological restoration is frequently offered as a partial solution to these changes because less stressed ecosystems may be more tolerant of novel changes in the environment (Temperton et al. 2004, Clewell and Aronson 2008). In this sense, restoration could provide a...

The residential sector consumes about 23% of the energy derived from wood (wood energy) in the U.S. An estimated error correction model with data from 1967 to 2009 suggests that residential wood energy consumption has declined by an average 3% per year in response to technological progress, urbanization, accessibility of non-wood energy, and other factors associated with a time trend such as increasing income per capita and number of houses. But the rising price of non-wood energy has had a positive effect on the consumption and offset the downward trend effect in the last decade. Residenti...

Non-native invasive plant species (NNIPS) pose a serious socio-ecological challenge due to their potential to replace and damage critical human-sustaining ecosystems (OTA 1993; Mack et al. 2000; Pimentel 2002). The impacts of non-native species are widespread and significant - altering ecosystem structure and function, threatening other species, and imposing human economic and cultural costs (Mack et al. 2000; Pfeiffer and Voeks 2008). In an increasingly globalized and human-dominated world, species from different bioregions are mixing at increasing rates through the opening of new...

Big sagebrush is an essential component of shrub-steppe ecosystems that is rapidly disappearing from the landscape. Recognizing this, it has become a target of restoration; however, current efforts using direct seeding have shown variable success and planting seedlings may provide a better option. Nonetheless, limited information is available on the nursery production of big sagebrush seedlings. This thesis aims to 1) further refine the cold storage component of sagebrush seedling nursery culture, and 2) investigate seed source variation in Wyoming big sagebrush (Artemisia tridentata ssp....

Douglas' dustymaiden, Chaenactis douglasii (Hook.) Hook. & Arn., is a widespread, inconspicuous, short-lived perennial wildflower that blooms in early summer and is found in basin sagesteppe to upper montane areas throughout the U.S. Intermountain West. The species is proving practical to grow for seed and is expected to be used for western rangeland rehabilitation. Through manual pollination experiments, C. douglasii was found to be only weakly self-fertile; 15% of flowers from geitonogamy and autogamy treatments yielded filled achenes. In contrast, 57% of outcrossed flowers produced...

Species distribution models for 147 bird species have been derived using climate, elevation, and distribution of current tree species as potential predictors (Matthews et al. 2011). In this case study, a risk matrix was developed for two bird species (fig. A2-5), with projected change in bird habitat (the x axis) based on models of changing suitable habitat resulting from changing climate and tree species habitat. Risk was evaluated for three time steps (2040, 2070, 2100) and based on two climate models and two emission scenarios (Hadhi vs. PCMlo).

Phyllolobium, a recently established genus from subgenus Pogonophace of Astragalus, contains about 20 species and four sections, mostly endemic to the Qinghai-Tibetan Plateau (QTP). The uplift of the QTP undoubtedly affected organismic evolution in the region, but further molecular dating in a phylogenetic context is required to test whether diversification is linked in particular to the intense uplift 3.6 million years ago (Ma).