Foliar ozone uptake rates of different-sized black cherry (Prunus serotina Ehrh.) trees were compared within a deciduous forest and adjacent openings in north-central Pennsylvania during one growing season. Study trees included open-grown seedlings and saplings, forest understory seedlings and saplings, and sunlit and shaded portions of mature canopy tree crowns. Instantaneous ozone uptake rate...

Wireless technology continues to experience rapid growth and development. With the ever increasing demand for wireless services and applications, more advanced tools are necessary to ensure the performance of these wireless systems. One of the most important tools for system development and radio planning are the radio propagation channel models. These models allow system designers and radio pl...

IntraspeciWc diversity can inXuence the structure of associated communities, though whether litter-based and foliage-based arthropod communities respond to intraspeciWc diversity in similar ways remains unclear. In this study, we compared the eVects of host-plant genotype and genotypic diversity of the perennial plant, Solidago altissima, on the arthropod community associated with living plant ...

Few studies have examined the combined effects of nutrition and water exclusion on the canopy physiology of mature loblolly pine (Pinus taeda L.). Understanding the impacts of forest management on plantation productivity requires extensive research on the relationship between silvicultural treatments and environmental constraints to growth. We studied the physiological responses of 18-year-old ...

Outdoor scenes require vegetation to make them look realistic. Current hardware cannot afford real-time rendering of these scenes because of the large number of polygons. Multiresolution modelling has been successfully presented as a solution to the problem of efficient manipulation of highly detailed polygonal surfaces. This article describes a new continuous multiresolution hardware-oriented ...

High compression of plant geometry is an important aspect in fast realistic visualization of plants. Hierarchical structuring plant morphology is a key factor for real time plant rendering, especially when pedestrian views, including both close-ups and far views, are requested. We present here a new geometric simplification method, called Viewdependent Hierarchical Foliage Simplification (VHFS)...

Plants are important objects in virtual environments. High complexity of shape structure is found in plant communities. Level of detail (LOD) of plant geometric models becomes important for interactive forest rendering. We emphasize three major problems in current research: the time consumption in LOD model construction and extraction, the balance between visual effect and data compression, and...

One of the most important challenges in real-time rendering of outdoor scenes is the representation of vegetation. This is due to the vast amount of polygons that are used to model vegetable species. The present automatic simplification algorithms produce acceptable results in the trunks and the branches, but not in the foliage of a tree. After simplification with the existing methods, the tree...

Colorado potato beetle, Leptinotarsa decemlineata (Say), feeding, development, and survival to adulthood were examined after continuously exposing large larvae to Bacillus thuringiensis subsp. tenebrionis-treated potato foliage from the field. In laboratory assays, the overall consumption and the length of period to become prepupae were determined for larvae, which began as 3rd and 4th instars,...

Host plant phenology (as influenced by seasonality) and light-mediated changes in the phenotypic and phytochemical properties of leaves have been hypothesised to equivocally influence insect herbivore performance. Here, we examined the effects of seasonality, through host plant phenology (late growth-season = autumn vs flowering-season = winter) and light environment (shade vs full-sun habitat)...