Treesearch

Previous stochastic models in harvest scheduling seldom address explicit spatial management concerns under the influence of natural disturbances. We employ multistage stochastic programming models to explore the challenges and advantages of building spatial optimization models that account for the influences of random stand-replacing fires. Our exploratory test models simultaneously consider timber harvest and mature forest core area objectives. Random fire samples are built into the model, creating a sample average approximation (SAA) formulation of our stochastic programming problem....

The Interagency Native Plant Materials Development Program outlined in the 2002 United States Department of Agriculture (USDA) and United States Department of Interior (USDI) Report to Congress encouraged use of native plant materials for rangeland rehabilitation and restoration where feasible. The Great Basin Native Plant Project is a cooperative project lead by the Bureau of Land Management (BLM) Plant Conservation Program and the United States Forest Service (USFS), Rocky Mountain Research Station that was initiated to provide information that will be useful to managers when making...

Forests store large amounts of carbon in forest biomass, and this carbon can be released to the atmosphere following forest disturbance or management. In the western US, forest fuel reduction treatments designed to reduce the risk of high severity wildfire can change forest carbon balance by removing carbon in the form of biomass, and by altering future potential wildfire behavior in the treated stand. Forest treatment carbon balance is further affected by the fate of this biomass removed from the forest, and the occurrence and intensity of a future wildfire in this stand. In this study we...

This paper tests the hypothesis that thinning and nitrogen fertiliser can increase the mass of wood produced per volume of water used (evapotranspiration) by plantations of Eucalyptus globulus. We have called this plantation water productivity (PWPWOOD) and argue that, for a given genotype, this term integrates the effects of management, site and climate on both production and evapotranspiration. This is done using annual estimates of wood production and evapotranspiration from age three years to harvest age (~age 10 years) in three E. globulus stocking density by nitrogen experiments. The...

Reaumuria is an arid adapted genus with a distribution center in Central Asia; its evolution and dispersal is investigated in this paper. Eighteen species of Reaumuria and nine species of two other genera in the Tamaricaceae, Tamarix and Myricaria, were sampled, and four markers ITS, rps16, psbB-psbH, and trnL-trnF were sequenced. The reconstructed phylogenetic tree is fundamentally consistent with previous morphological classification, except that R. soongorica, sometimes considered to be a separate genus or subgenus, is completely nested within Reaumuria. The ancestral area of the genus...

The Tamaricaceae contains about eighty species [1] and four genera: Tamarix, Myricaria, Reumuria, and Hololachna [2]. This family, and Frankeniaceae, are defined as the salt-gland anatomical lineage [3]. Myricaria consists of about twelve - thirteen species [4-7] and occurs in Northern Temperate zone of Eurasia, mainly along the Asian mountains. There are eight species in Himalayas, many are endemic, thus forming a center of diversity for Myricaria.

The Anthropocene will have fundamental effects on the species composition, function, and structure of the ecosystems of the world. Land management agencies such as the USDA Forest Service will need to adapt their policies and conservation activities to avoid engaging in continuous conflict with natural processes and unfamiliar biotic assemblages. Conservation paradigms need to evolve to face the Anthropocene without abandoning the wisdom and relevance of paradigms from previous eras of conservation activity. A new paradigm for conservation in the Anthropocene could be summarized as...

Protected areas are a cornerstone for biodiversity conservation, but they also provide amenities that attract housing development on inholdings and adjacent private lands. We explored how this development affects biodiversity within and near protected areas among six ecological regions throughout the United States. We quantified the effect of housing density within, at the boundary, and outside protected areas, and natural land cover within protected areas, on the proportional abundance and proportional richness of three avian guilds within protected areas. We developed three guilds from...

The sources of political attitudes are among the most studied phenomena of modern politics. Moving away from the traditional focus on party systems, the demographic characteristics of voters, or political socialization, I consider instead how memory and narrative shape political consciousness. Specifically, I focus on how culturally sanctioned memories of warfare influence the political attitudes of 24 Vietnam veterans. I compare two groups of Vietnam veterans who went to Vietnam in support of the war and political status quo, but who returned with opposing attitudes toward war. How can we...

Natural ecosystems in the semiarid West face many stressors. Among the most challenging are those associated with invasive plant species. One invader that has had great impact over the last 100 years is the annual grass known as cheatgrass (Bromus tectorum). A few years ago, I made two observations that both confirmed and broadened my perception of this plant. In the first, I saw it growing on sodden roofs in an historic community near the Mississippi River. I was reminded that the scientific name roughly means "brome grass that grows on roofs" and I gained insight into its long coexistence...