PACs (polycylic aromatic compounds) are air pollutants formed in incomplete combustion, e.g., vehicle engines. Vegetation can potentially remove substantial amounts and act as bioindicators of these pollutants. Increased knowledge the pollutant removal efficiencies different tree species is essential for understanding potential benefits trees provide urban residents. We investigated leaf/needle...

Information regarding the relationship between photosynthesis and the complex of internal factors encompassed by the term, age, may be of interest either from the point of view of basic science or of practical application. The literature on this subject appears to be rather meager. SINGH and LAL (2) working with different aged leaves of flax, sugar cane, and wheat found that the rates of photos...

Browsing by herbivores profoundly affects the nature and extent of woody plant communities through a variety of mechanisms, including alterations to disturbance regimes (such as fire frequency), indirect effects on nutrient cycling and soil fertility, and changes to net primary production (Hobbs 1996). Plants have evolved myriad ways to avoid being eaten, ranging from the development of spiny, ...

—We addressed the following question: Do conifers within aspen stands (conifer invasion) increase bird species diversity in western landscapes? We tested the hypotheses that bird species diversity, measured as species richness or with the Shannon-Weiner diversity index, responds to aspen-conifer ratios (from 0% to 100% conifer) in a quadratic manner with a maximum occurring at an intermediate r...

A 55-YR-OLD man with endstage renal disease presented for emergent removal of an infected arteriovenous dialysis graft. This patient had multisystemic disease, including hepatitis C, human immunodeficiency virus, cardiomyopathy, and atrial fibrillation. He also had a history of left internal jugular thrombosis and right common carotid septic pseudoaneurysm, corrected via partial sternotomy. A c...

The conifer leaf model LIBERTY (Leaf Incorporating erties of individual leaves (Aber, 1994). Leaves are an Biochemistry Exhibiting Ref lectance and Transmittance important component of forest canopies, and it is the Yields) is an adaptation of radiative transfer theory for deconcentration of their biochemical constituents, namely, termining the optical properties of powders. LIBERTY pigments, w...