Treesearch

There is an urgent need for next-generation smoke research and forecasting (SRF) systems to meet the challenges of the growing air quality, health and safety concerns associated with wildland fire emissions. This review paper presents simulations and experiments of hypothetical prescribed burns with a suite of selected fire behaviour and smoke models and identifies major issues for model improvement and the most critical observational needs. The results are used to understand the new and improved capability required for the next-generation SRF systems and to support the design of the Fire...

Major atmospheric circulation patterns for wildfires have been identified in regions with boreal, Mediterranean, and semiarid climates. This study investigates such patterns in the monsoon regions of China, where the climate is controlled by multiple atmospheric systems and wildfires have large spatial variability. We identified three patterns. The first pattern was characterized by a high‐pressure ridge in northeast China and contributed to wildfires by creating warmer and drier conditions. The second, meridional pattern contributed to wildfires in north, central, and south China by...

A new species of scorpionfly, similar to Panorpa helena and Panorpa insolens, but lacking 2–4 long, stout, black setae on the male basistyles apices and possessing long barbs on the apices of the male ventral parameres, is described from the Bluegrass Region of Kentucky.

In road construction projects across the United States, erosion control methods (e.g., erosion control blankets [ECBs]), are mandated to stimulate seedbed regeneration and prevent soil loss. Previous reports have suggested that snakes are vulnerable to entanglement in ECBs. We conducted a literature review, field surveys, and an entanglement experiment to examine what factors increase a snake’s risk of ECB entanglement. Our literature review produced reports of 175 reptiles entangled in mesh products, 89.1% of which were snakes, with 43.6% of snake entanglements occurring in erosion...

A 20-year experiment was reported on the effects of climate variability and management in California's ponderosa pine plantations. Pine trees were grown in three different climatic and edaphic zones treated with herbicide to reduce competition from understory plants and/or fertilizer to stimulate growth. We found that management increased tree growth and, in most but not all cases, the combination of understory suppression and fertilization stimulated productivity beyond the expected growth potential of each site. In addition, wet sites have the most productive forests overall, but they...

Potential risk for disruption to supply of raw materials for bio-based industrial sites from natural disasters has received little attention in site evaluations even though these risks may be significant. Biomass supply in the form of roundwood, forest and agricultural residues, or dedicated short rotation plantations are especially subject to disruptions from meteorological disturbances such as floods, wind and ice storms. The objective of this study was to account for risk from natural disasters in assessing the economic supply of biomass for the Eastern United States in a geospatial...

Over the past two decades, the United States government conducted detailed analyses of the potential of a biobased national energy strategy that produced four unified studies, namely the 2005–2016 US Billion-Ton Study and updates. With each effort, better perspective was gained on the biophysical potential of biomass and the economic availability of these resources on a national scale. It was also apparent that many questions remained, including crop yields, logistical operations, and systems integration across production and harvest. These reports accentuated the need for improving...

Estimates of growth or change in a forest population parameter for a specific length of time, such as cubic meters of wood per hectare per year, are often made from sample observation intervals of di erent lengths of time. For instance, a basic building block of growth estimators in forest inventory systems is often the annual mean of the first di erences of all observations for a particular year, regardless of observation interval length. The aggregate di erences between successive observations on re-measured forest sample plots can be viewed as a linear combination, while forest growth...

Larger and more frequent disturbances are motivating efforts to accelerate recovery of foundational perennial species by focusing efforts into establishing island patches to sustain keystone species and facilitate recovery of the surrounding plant community. Evaluating the variability in abiotic and biotic factors that contribute to differences in survival and establishment can provide useful insight into the relative importance of these factors. In the western United States, severe degradation of the sagebrush steppe has motivated substantial efforts to restore native perennial cover, but...

The focus of investigation in this study was to consider the potential of arthropods in the dissemination of the bacterium involved in drippy blight disease, Lonsdalea quercina. Arthropod specimens were collected and tested for the presence of the bacterium with molecular markers. The bacteriumL. quercina was confirmed on 12 different insect samples fromthree orders (Coleoptera, Hemiptera, and Hymenoptera) and eight families (Buprestidae, Coccinellidae, Dermestidae, Coreidae, Pentatomidae and/or Miridae, Apidae, Formicidae, and Vespidae). Approximately half of the insects found to carry...