chlorophyll-a and sulfuric-acid

A study was conducted to characterize marigold stress response to polycyclic aromatic hydrocarbons (PAHs) (oxidative stress inducers) with and without sulfuric acid (S.Acid; pH 3) (acid-stress inducer), and to evaluate reactive oxygen species (ROS) scavenging activity of mannitol (Mann). Marigold (Calendula officinalis) seedlings were grown in a greenhouse and fumigated with fluoranthene (FLU), phenanthrene (PHE), Mann, and S.Acid individually and in various combinations for 40 days. Various physiological and biochemical parameters among others were analyzed using standard methods. The results revealed that fumigation of FLU induced oxidative stress to the plants via ROS generation leading to negative effects on photosynthesis at near saturating irradiance (A

Topics: Calendula; Chlorophyll; Drug Synergism; Fluorenes; Fumigation; Mannitol; Oxidative Stress; Phenanthrenes; Photosynthesis; Polycyclic Aromatic Hydrocarbons; Reactive Oxygen Species; Sulfuric Acids

A continuing rise in acid deposition can cause forest degradation. In China, acid deposition has converted gradually from sulfuric acid deposition (SAD) to nitric acid deposition (NAD). However, the differing responses of photosynthesis and growth to depositions of sulfuric vs. nitric acid have not been well studied. In this study, 1-year-old seedlings of Schima superba, a dominant species in subtropical forests, were treated with two types of acid deposition SO4 (2-)/NO3 (-) ratios (8:1 and 0.7:1) with two applications (foliar spraying and soil drenching) at two pH levels (pH 3.5 and pH 2.5) over a period of 18 months. The results showed that the intensity, acid deposition type, and spraying method had significant effects on the physiological characteristics and growth performance of seedlings. Acid deposition at pH 2.5 via foliar application reduced photosynthesis and growth of S. superba, especially in the first year. Unlike SAD, NAD with high acidity potentially alleviated the negative effects of acidity on physiological properties and growth, probably due to a fertilization effect that improved foliar nitrogen and chlorophyll contents. Our results suggest that trees were damaged mainly by direct acid stress in the short term, whereas in the long term, soil acidification was also likely to be a major risk to forest ecosystems. Our data suggest that the shift in acid deposition type may complicate the ongoing challenge of anthropogenic acid deposition to ecosystem stability.

Topics: China; Chlorophyll; Ecosystem; Forests; Nitric Acid; Nitrogen; Photosynthesis; Seedlings; Soil; Sulfuric Acids; Tracheophyta; Trees

Sunpatiens were exposed separately or combined to ozone gas (130 ppb), fluoranthene (10 microM) and sulphuric acid mists (pH 3) sprayed as simulated pollutants in chamber conditions for 21 d. The treatments negatively affected the gas (CO(2) and moisture) exchange, leaf chlorophyll fluorescence, and the leaf-quality expressed in chlorophyll value (SPAD). Fluoranthene and the acid individual negative effects on the measured eco-physiological variables were nearly the same on Sunpatiens; their effects became aggravated on combining the duo. The foliar symptom assessments of chlorosis, necrosis and stippling revealed severe damages in ozone containing treatments compared with other treatments. The presence of fluoranthene exuberate ozone negative effects on some of the plant eco-physiological status. Where mannitol (1mM) additions were contained in treatments, mitigation effects of the negative impact of pollutants resulted. These findings indicated that Sunpatiens can be used as an active bioindicator of singular and multiple pollutants in field conditions.

Topics: Air Pollutants; Carbon Dioxide; Chlorophyll; Chlorophyll A; Environmental Monitoring; Fluorenes; Fluorescence; Impatiens; Ozone; Photosynthesis; Plant Leaves; Plant Transpiration; Sulfuric Acids

Ramalina maciformis and Ramalina lacera were exposed to different solutions and UV-B to seek for alterations in the PSII photosynthetic quantum yield (F(v)/F(m)), in response to chemicals and radiation. For R. maciformis, significant alterations of the F(v)/F(m) ratio occurred only in response to different bisulphite solutions. The F(v)/F(m) ratio decreased most in R. maciformis and R. lacera following exposure to 5 and 1 mM bisulphite, respectively. Significant differences in F(v)/F(m) ratios were observed for R. lacera in response to different solutions and light at different wavelengths, this being synergistic. The PSII system was unaffected by simulated acid rain in both lichens. R. maciformis, in particular, may survive limited acid rain exposure owing to high Ca oxalate accumulation. The F(v)/F(m) ratio decreased most in R. lacera following short-term exposures to CuSO(4), suggesting that this species is more sensitive to Cu ions under acidic conditions.

Topics: Acid Rain; Air Pollutants; Chlorophyll; Copper; Copper Sulfate; Ecosystem; Fluorescence; Lichens; Light; Nitric Acid; Photosynthesis; Photosystem II Protein Complex; Plant Proteins; Sulfites; Sulfur; Sulfuric Acids; Time Factors; Ultraviolet Rays