Impact of simulated acid rain on soil microbial community function in Masson pine seedlings

Background Accompanying its rapid economic development and population growth, China is the world's third largest acid rain region, following Europe and North America. The effects of acid rain on forest ecosystem were widely researched, including the growth, the nutrient of the leaf and soil, and so on. However, there are few reports about the effects of acid rain on the soil microbial diversity. This study investigated the effects of acid rain on soil microbial community function under potted Masson pine seedlings (Pinus massoniana Lamb). Results After 7 months of treatment with simulated acid rain, the low acid load treatment (pH 5.5) stimulated soil microbial activity, and increased soil microbial diversity and richness, while the higher levels of acid application (pH 4.5, pH 3.5) resulted in lower soil microbial activity and had no significant effects on soil microbial diversity and richness. Principal component analysis showed that there was clear discrimination in the metabolic capability of the soil microbial community among the simulated acid rain and control treatments. Conclusion The results obtained indicated that the higher acid load decreased the soil microbial activity and no effects on soil microbial diversity assessed by Biolog of potted Masson pine seedlings. Simulated acid rain also changed the metabolic capability of the soil microbial community.

Concentración de contaminantes SO2, NO2 y correlación con H+, SO4-2 y NO3- durante la temporada de lluvias en la Zona Metropolitana de Guadalajara, Jalisco, México / Concentration of pollutants SO2, NO2 and correlation with H+, SO4-2 and NO3- during wet season in the Metropolitan Zone of Guadalajara, Jalisco, Mexico

In the last 30 years, the Metropolitan Zone of Guadalajara (ZMG) has experienced a quick urban and industrial growth, situation which results in high rates of pollution and poor air quality harmful to the health of the population. The main purpose of this work was to analyze the SO2 and NO2 in the air, as well as ions H+, SO 4-2 and NO3- during the wet season of 2005. Results of the network of monitoring stations showed significant acidity in north-northwest and southeast of the study area. The maximum concentrations of SO 4-2 occurred in southeast and south, while the maximum NO3- was found in the south. Maximum levels of SO2 and NO2 occurred in the dry season, but it decreased in wet season. The higher frequency about acidity produced by NO2 is caused by mobile sources as the primary indicator.

En los últimos 30 años, la Zona Metropolitana de Guadalajara (ZMG) ha experimentado un acelerado crecimiento urbano-industrial, realidad traducida en contaminantes nocivos para la salud de la población. El objetivo de este trabajo fue analizar la concentración de dióxido de azufre (SO 2) y de nitrógeno (NO2) en el aire, así como, los iones hidrógeno (H+), sulfatos (SO 4-2) y nitratos (NO3-) durante la temporada de lluvias del año 2005. Mediante una red de estaciones de monitoreo, se obtuvieron resultados que revelaron acidez significativa al norte-noroeste y sureste. Las concentraciones máximas de SO4-2 ocurrieron al sureste y sur, mientras que, las de NO3- se localizaron al sur. Los niveles máximos de SO2 y NO2 sucedieron en el período seco, disminuyendo en el húmedo. Se observó mayor frecuencia de acidez por NO2 siendo el indicador principal las fuentes móviles.

Acid rain and its ecological consequences.

Acidification of rain-water is identified as one of the most serious environmental problems of transboundary nature. Acid rain is mainly a mixture of sulphuric and nitric acids depending upon the relative quantities of oxides of sulphur and nitrogen emissions. Due to the interaction of these acids with other constituents of the atmosphere, protons are released causing increase in the soil acidity Lowering of soil pH mobilizes and leaches away nutrient cations and increases availability of toxic heavy metals. Such changes in the soil chemical characteristics reduce the soil fertility which ultimately causes the negative impact on growth and productivity of forest trees and crop plants. Acidification of water bodies causes large scale negative impact on aquatic organisms including fishes. Acidification has some indirect effects on human health also. Acid rain affects each and every components of ecosystem. Acid rain also damages man-made materials and structures. By reducing the emission of the precursors of acid rain and to some extent by liming, the problem of acidification of terrestrial and aquatic ecosystem has been reduced during last two decades.

Study of precipitation chemistry over an industrial city

The growing trend of industrialization has marked impact on the atmospheric chemistry around the globe. Such impacts are also predicted for developing countries like India. Acid precipitation due to secondary pollutants is one of them. The present investigation was conducted with an aim of studying the precipitation chemistry over Asansol city, India during the monsoon season. The rain water samples, collected on event basis during the period of June to September 2006, were analyzed for HCO3[-], C1[-], S04[2-], NO3[-], NH4[+], K[+], Na[+], Mg[2+], Ca[2+] and pH using standard procedures. The study revealed that the precipitation was alkaline in nature with mean pH value of 6.08. Dominant anion in rain water samples was HCO3[-] [36%], whereas Ca[2+] was highest among the cations [53%]. The observed acidic events, based on pH value, were only 17%, indicating the alkaline components effectively neutralize rain water over the area. This was also supported by the total alkaline to acid ion ration of 1.05. The ratio of [NO3[-]+C1[-]] and SO4[2-] was >1, indicating that acidic properties were influenced by HNO3 and HC1. In the ratio between [Ca[2+]+NH4[+]] and [NO3[-]+SO4[2-]], values >1 were obtained, indicating significant alkaline influence, which effectively prevented acid depositions in the area

Lo que debemos saber para salvar la planeta de la contaminación / What should know in order to save the planet of the contamination

El documento trata sobre: la contaminación ambiental, capa de ozono, lluvia acida, contaminacion atmosférica etc.(au)

Proposal for a study of the health hazards of gas emission from Poas volcano, Costa Rica

In Central America, volcanoes and earthquakes pose major environmental threats to populations. In particular, degassing volcanoes may adversely affect the health of local inhabitants. For example the recent gas emission crisis at Masaya, Nicaragua, which began in 1979, exposed thousands of people to hazardous levels of SO2 and sulphate aerosols downwind. During different phases of their activity other volcanoes may emit toxic plumes into populated areas, e.g. San Cristóbal, Nicaragua. Poás, a composite basaltic-andesite cone situated on the Cordillera Central, of Costa Rica, rises 1300mn above its base at 1400m. Historically it has been in a state of nearly continuous mild activity. The active crater is roughly circular with a diameter of about 1100m and a crater lake has existed since 1965. Until recently the heat input from the presumed shallow magma body was balanced by the heat output from the fumaroles and crater lake, with degassing occurring through the central vent beneath the lake. Since 1987, gas emissions from Poás volcano have increased and have been reported to affect vegetation and cause health problems in the populated areas downwind. During this period the hot crater lake has undergone an annual cycle in which its level rises and falls with the wet and dry seasons; in the dry season it becomes strongly acid because of enhanced evaporation and concentration of anions. Therefore, in addition to gas from the crater fumaroles the plume can contain copious amounts of concentrated acid aerosol from the lake which may greatly increase the health hazard from inhaling contaminated air. The changes at Poas probably reflect a dramatic increase in power input consistent with the injection of shallow magma beneath the crater lake and wich may have coincided with an increase in the flux of gases and aerosols since 1986