Acid Deposition Monitoring Network in East Asia

Acid deposition monitoring covers four environmental media - wet deposition, dry deposition, soil and vegetation, and inland aquatic environment.Monitoring for wet and dry deposition are implemented in order to measure concentrations and fluxes of acidic substances deposited to the ground, while monitoring for soil and vegetation, and inland aquatic environment are being implemented to assess adverse impacts on terrestrial and aquatic ecosystems.Monitoring

1. Wet Deposition:
Monitoring Interval - every 24 hours or every precipitation event for an urban, rural or remotesite
Major Parameters - Precipitation anaysis: pH, electrical conductivity (EC), concentrations of
sulfate (SO42-), nitrate (NO3-) and other ions

2. Dry Deposition:

Monitoring Interval - every day to two weeks, or every hour when measured by automatic instruments
Major Measurements - Gases: concentrations of sulfur dioxide (SO2), nitrogen dioxide (NO2), ozone(O3) and others Particulate components.

3. Soil and Vegetation:
Monitoring Interval - once three to five year
Major Parameters - Soil:pH, concentrations of exchangeable ions and effective cation exchange capacity (ECEC) Vegetation (forest): survey of tree decline, and general description of forest.

4. Inland Aquatic Environment:

Monitoring Interval - More than four times a year
Major Parameters - Inland water :pH, electrical conductivity (EC), alkalinity and ions

New Yorks Acid Deposition Monitoring Network

New York monitors and tests for acid deposition through the New York State Atmospheric Deposition Monitoring Network, which was designed in 1985 to carry out requirements of the State Acid Deposition Control Act (SADCA). Measurements of acid deposition and related quantities are used to assess the effectiveness of sulfur control policy and other strategies aimed at reducing the effects of acid rain.

The network's objectives are:

• Provide a consistent, quality-assured, long-term acid deposition database.
• Measure acid deposition in sensitive receptor areas.
• Measure acid deposition in urban and upwind areas.
• Use these data to perform spatial and temporal analyses of acid deposition, its precursors, and its effects.
• Track the effectiveness of programs to reduce acid deposition precursor emissions.

Site Classifications
The network is composed of three classes of monitoring sites which differ by the amount and kind of instrumentation used. They are designated "Type 3," "Type 2," and "Type 1."


Type 3: Sites have two types of instrumentation. The first is a tipping bucket rain/snow gauge to measure the amount of precipitation. The output signal is connected to either a recorder or a telemetry unit. The second device is a Viking Hyetometer which is a bucket type collector designed to collect samples under wet or dry conditions. Wet deposition samples are gathered in the lined buckets when precipitation is occurring. Because no adequate methodology has been established for analysis of dry side samples, only the wet side samples are analyzed.

Type 2 :Sites have all the devices operated at a Type 3 site and they also incorporate continuous monitoring instrumentation to measure the ambient concentration of selected components. These instruments are connected via telemetry to a central computer. Beginning in 1991, several low-level SO2 and ozone analyzers have been installed and are in operation. Type 2 Sites are also designed to measure relative humidity, temperature, and atmospheric pressure. Additional analyzers may be added, given adequate resources.

Type 1 :Sites, in addition to having the instrumentation used at Type 2 Sites, also measure wind speed and direction, and calculate horizontal sigma (wind direction variability).

REAL-TIME MEASUREMENT OF ACID RAIN

A microprocessor-based acid rain monitor was used to make real-time measurements of conductivity and pH of rainwater within individual storms. The automated measurements were compared with laboratory analyses of a subset of the samples taken. The laboratory measurements tended to overestimate the pH because of temperature induced changes in dissociation and Henry's Law constants affecting ionic compounds in the rainwater.

 The measurement fact due to these effects may result in average hydrogen ion concentrations being underestimated by approximately 10 to 15% at UK sites. The greatest systematic discrepancies would be anticipated at highly polluted sites and during low temperature acidic episodes. The concept of a rainwater acid fraction was investigated and found to be useful for quality control and interpretative purposes. 

The field measurement of conductivity of low ionic strength samples was slightly lower than the corresponding laboratory measurement, possibly caused by limited resolution of the conductivity probe or dissolution of fine particulate material.

ECOSYSTEM RECOVERY FROM ACID DEPOSITION

Ecosystem recovery is a phased process that involves the reversal of degraded chemical and biological conditions.Recovery from acid deposition involves decreases in emissions resulting  from regulatory controls, which in turn lead to reductions in acid deposition and allow chemical recovery. Chemical recovery is characterized by decreased concentrations of sulfate, nitrate, and aluminum in soils and surface waters. If sufficient, these reductions will eventually lead to increased pH and ANC, as well as higher concentrations of base cations. As chemical conditions improve, the potential for the second phase of ecosystem recovery, biological recovery, is greatly enhanced.

An analysis of the scientific literature suggests that the following five thresholds can serve as indicators of chemical recovery. If chemical conditions in an ecosystem are above these thresholds, (or in the case of aluminum, are below the threshold) it is unlikely that the ecosystem has been substantially impaired by acid deposition. Conversely, if chemical conditions are below these thresholds, (or in the case of aluminum, above the threshold) it is likely that the ecosystem has been, or will be, impaired by acid deposition.

As chemical conditions in soils and surface waters improve, biological recovery is enhanced. Biological recovery is likely to occur in stages, since not all organisms can recover at the same rate and may vary in their sensitivity to acid deposition.The current understanding of species’ responses to improvements in chemical conditions is incomplete, but research suggests that stream macro-invertebrates may recover relatively rapidly, while lake zooplankton may need a decade or more to fully re-establish. Fish populations in streams and lakes should recover in 5-10 years following the recovery of the cro-invertebrates and zooplankton which serve as food sources. It is possible that, with improved chemical conditions and the return of other members of the aquatic food web, the stocking of streams and lakes could help to accelerate the recovery of fish

Acid Rain Research

The researchers discovered that acid rain inhibits a swampland bacteria from producing methane, a greenhouse gas. Methane, a gas that contributes to warming our planet, is produced by natural processes and human activities. Increased amounts of methane and other greenhouse gases in our atmosphere are warming the Earth beyond its average temperature.

Carbon, heat and moisture are known to influence methane production by members of the Archaea, single-celled creatures. Under normal conditions, these microbes consume organic carbon in the soil for energy and release methane as a byproduct. Wetlands provide an ideal environment for these microbes. When acid rain drops sulfate onto wetlands, another type of bacteria, ones that reduce sulfate are able to out compete the Archea, limiting the total production of methane.

Wetlands may produce as much as 320 million tons of methane annually but only about half of that, or 160 million tons, is ultimately released to the atmosphere. The other 160 million tons never makes it to the atmosphere because it is destroyed via oxidation as it moves from wet soils below the water table through dry soil to the surface. Despite substantial oxidation, natural wetlands remain the single largest source of methane emission accounting for about one third of the global annual total methane.

"It's a complicated process because multiple factors at microscopic to global scales interact in these processes," said Elaine Matthews, a scientist at NASA's Goddard Institute for Space Studies (GISS), New York. Matthews is co-author of the study on acid rain and methane in wetlands. "The maximum emission of methane from wetlands occurs when conditions are warm and wet, while the biggest reduction in methane emissions is achieved when the location of wetlands, sulfates contained in acid rain, high temperatures and substantial precipitation all come together, to reduce optimal methane emissions from wetlands." These factors vary over time and space.

Sites at High Risk from the Hazards Associated with Acid Rain

Acid rain only causes indirect damage to living human beings, primarily through its reactions with Volatile Organic Compounds (VOCs) to form ground-level Ozone (smog), it causes tremendous damage to soil fertility, aquatic life, and durable inorganic materials such as stone and metals. Some of the greatest measurable effects of acid rain can be observed on human constructions, particularly old buildings with facades built of corrosion-prone metals such as copper and porous stone such as limestone. 

Endangered Heritage Sites due to acid rain:

1. LESHAN GIANT BUDDHA, MOUNT EMEI (China, Buddhist)
The Leshan Buddha has fallen victim to pollution emanating from unbridled development in the region. In this case, the culprit has been determined to be the growing number of coal fired power plants located near the Giant Buddha, specifically, the toxic gases that their smokestacks spew into the air; these eventually return to the earth as acid rain. Over time, the Buddha's nose has turned black and the curls of his hair have begun to fall from his head. The local government has shut down several factories and power plants in close proximity to the Leshan Giant Buddha, which has stopped the blackening of his face from soot; however, acid rain continues to compromise the structural integrity of this masterpiece. The Leshan Giant Buddha, which was designed carefully to survive millennia of floods and earthquakes, is now at high risk of rapid deterioration from the unbridled pace of industrial development in western China.

2. ACROPOLIS OF ATHENS (Greece, Ancient Greek)
In recent decades, as Greece has experienced substantial economic expansion and development, pollutants and heavy vehicle emissions from the booming modern city of Athens have contributed to acid rain in the region. The monumental and sculptural stone of choice for the ancient Greeks, marble, is highly susceptible to heavy surface degradation from even low levels of acid rain. The Parthenon’s magnificent marble relief frieze panels, for instance, have been chemically transformed by acid rain into soft gypsum. As details are lost and the chemical transformation soaks deeper into the marble on these vital monuments, pieces of them have begun to crack and fall off, with structural collapse a possibility in the not-so-distant future. Further complicating the situation is the seismically-active nature of the region, as earthquakes would have a far greater effect on marble constructions that have slowly transformed into gypsum than with unaltered marble.

3. TAJ MAHAL (India, Mughal Islam)
The Taj Mahal is India’s preeminent tourist destination, attracting between two and four million visitors annually. In an effort to control the deleterious effects of pollution, tourist traffic is not allowed near the site, with most visitors riding in by electric bus from nearby carparks. This has not, however, slowed down the degradation of the Taj Mahal’s marble facades from acid rain generated from local foundries and an oil refinery. The once brilliant-white Taj has been losing its luster, dulling into a sickly pale shade.

4. DAMPIER ROCK ART COMPLEX (Australia, Australian Aboriginal)
The Burrup Peninsula’s rock art sites have been listed as endangered by the National Trust of Australia, but industrial expansion since 1963 across more than 25% of the rock art area has posed severe threats to the site. Much of the heaviest (mining and petrochemical) industry is located immediately adjacent to some of the most sensitive collections of artwork. Acid rain from this has begun to erase many of the carefully, but often shallowly, engraved rock surfaces, and studies by archaeologists and geologists have postulated that most of the rock art will disappear completely by the middle of the 21st century.

5. LONGMEN GROTTOES (China, Buddhist)
The Longmen Grottoes are arguably the most famous ancient sculptural site in China. Located in Henan Province and positioned on two opposing bluffs above the Yi River, most of the artwork is Buddhist in nature and dates to the late Northern Wei and Tang Dynasties (316-907 AD). 2345 niches were carved from the rock, densely worked over the space of approximately a kilometer to the north and south, and they house more than 100,000 statues (also carved from the rock). Accompanying inscriptions bear more than 300,000 Chinese characters and are a treasure trove of historical and linguistic data. The Longmen Grottoes are a masterpiece of Buddhist art and are considered one of the world`s most important sculptural sites.

Effect Of Acid Rain On Humans

Most importantly, acid rain can affect health of a human being. It can harm us through theatmosphere or through the soil from which our food is grown and eaten from. Acid rain causes toxic metals to break loose from their natural chemical compounds. Toxic metals themselves are dangerous, but if they are combined with other elements, they are harmless.They release toxic metals that might be absorbed by the drinking water, crops, or animals that human consume. These foods that are consumed could cause nerve damage to children or severe brain damage or death. Scientists believe that one metal, aluminum, is suspected tolerate to Alzheimer’s disease. One of the serious side effects of acid rain on human is respiratory problems.

 The sulphur dioxide and nitrogen oxide emission gives risk to respiratory problems such as dry coughs, asthma, headaches, eye, nose, and throat irritation.Polluted rainfall is especially harmful to those who suffer from asthma or those who have hard time breathing. But even healthy people can have their lungs damaged by acid air pollutants. Acid rain can aggravate a person’s ability to breathe and may increase disease which could lead to death. In 1991, the United States and Canada signed an air quality agreement. Ever since that time, both countries have taken actions to reduce sulphur dioxide emission. The United States agree to reduce their annual sulphur dioxide emission by about ten million tons by the year 2000. A year before the agreement, the Clean Air Pact Amendment tried to reduce nitrogen oxide by two million tons. This program focused on the source that emits nitrogen oxide, automobiles and coal-fired electric utility boilers. Reducing nitrogen oxide emission in a utility plant starts during the combustion phase. A procedure called over fire air is used to redirect a fraction of the total air in the combustion chamber.

To reduce sulphur dioxide emission utility plants are required to do several steps by the Clean Air Act Amendment.Before combustion, these utilities plants have to go through a process call coal cleaning. This process is performed gravitationally. Meaning, it is successful in removing pyritic sulphur due to its high specific gravity, but it is unsuccessful in removing chemically bound organic sulphur. This cleaning process is only limited by the percent of pyritic sulphur in the coal. Coal with high amount of pyritic sulphur is coal in higher demands. Another way to reduce sulphur dioxide before combustion is by burning coal with low sulphur content. Low sulphur content coals are called bituminous coal. This process in reducing sulphur dioxide is very expensive due to the high demand of bituminous coal.Acid rain is an issue that can not be over looked. This phenomenon destroys anything it touches or interacts with it. When acid rain damages the forest or the environment it affects humans in the long run. Once forests are totally destroyed and lakes are totally polluted animals begin to decrease because of lack of food and shelter. If all the animals, which are our food source, die out, humans too would die out.