Photochemical processes on ground and airborne surfaces have been suspected to lead to production of HONO in the sunlit lower troposphere, e.g. upon light activation of humic acids followed by reaction with adsorbed NO(2). Here, we used tannic and gentisic acids as proxies for atmospheric polyphenolic compounds to obtain further insights into the photoenhanced NO(2) conversion to HONO, which is...

The effects of natural sunlight and microbial decomposition on DOC, DON, and DOP were investigated along the salinity gradient of a temperate coastal plain estuary. The impact of sunlight-irradiated DOM on bacterial properties (bacterial abundance, production, bacterial growth efficiency [BGE]) was also followed. Surface-water light levels resulted in no detectable abiotic production of NH4 or ...

Massive coral species play a key role in coral reef ecosystems, adding significantly to physical integrity, long term stability and reef biodiversity. This study coupled the assessment of the distribution and abundance of 4 dominant massive coral species, Diploastrea heliopora, Favia speciosa, F. matthaii and Porites lutea, with investigations into species-specific photoacclimatory responses wi...

KO E H N, A.C. (Alabama A&M University, Normal, AL 35762) AND R.L. DOUDRICK (Southern Institute of Forest Genetics, Saucier, MS 39574). Diurnal patterns of chlorophyll fluorescence and CO, fixation in orchard grown Torreya ta.n’jdiu (Am.). Bull. Torrey Bot. Sot. 126:93398. 1999.-Chlorophyll fluorescence and CO, fixation measurements were taken on sunny days in October, 1996, on three Torreyu ta...

Laser biostimulation has been found effective in treatment of wound healing and inflammatory conditions. The nature and characteristics of laser light is different from natural light and of conventional light sources. Specifics of the laser include spectral coherence, temporal coherence and spatial coherence [1,2]. In addition, some lasers emit polarized photons and parallel beam. Laser with th...

Some epiphytic Hymenophyllaceae are restricted to lower parts of the host (< 60 cm; 10-100 μmol photons m(-2) s(-1)) in a secondary forest of Southern Chile; other species occupy the whole host height (≥ 10 m; max PPFD > 1000 μmol photons m(-2) s(-1)). Our aim was to study the photosynthetic light responses of two Hymenophyllaceae species in relation to their contrasting distribution. We determ...