How can pollution affect plants

Submission closed. Overview Articles Authors Impact. About this Research Topic Environmental contamination as a consequence of anthropogenic activities has become a global concern. Keywords : Plant physiology, Environmental Contamination, Emerging Contaminants, Climate changes, Phytoremediation Important Note : All contributions to this Research Topic must be within the scope of the section and journal to which they are submitted, as defined in their mission statements.

Topic Editors. Views Demographics No records found total views article views article downloads topic views. Top countries. Top referring sites. Injury ranges from visible markings on the foliage, to reduced growth and yield, to premature death of the plant. The development and severity of the injury depends not only on the concentration of the particular pollutant, but also on a number of other factors.

These include the length of exposure to the pollutant, the plant species and its stage of development as well as the environmental factors conducive to a build-up of the pollutant and to the preconditioning of the plant, which make it either susceptible or resistant to injury. In Ontario, air pollutants injurious to vegetation can generally be classed as either local or widespread. Local pollutants are those emitted from a specific stationary source and result in a well-defined zone of vegetation injury or contamination.

Most common among the local pollutants are sulfur dioxide, fluorides, ammonia and particulate matter. Widespread pollutants consist primarily of "oxidants". Ozone, the major component of oxidants, is produced in the atmosphere during a complex reaction involving nitrogen oxides and reactive hydrocarbons, components of automobile exhausts and fossil fuel combustion.

As this process proceeds only in sunlight, it is called a photo-chemical reaction. The vegetation injury, which can result from oxidant build-up in the air, can occur over large rural areas covering hundreds of square kilometres. Air pollution injury to plants can be evident in several ways. Injury to foliage may be visible in a short time and appear as necrotic lesions dead tissue , or it can develop slowly as a yellowing or chlorosis of the leaf. There may be a reduction in growth of various portions of a plant.

Plants may be killed outright, but they usually do not succumb until they have suffered recurrent injury. Ozone is the main pollutant in the oxidant smog complex. Its effect on plants was first observed in the Los Angeles area in Since then, ozone injury to vegetation has been reported and documented in many areas throughout North America, including the southwestern and central regions of Ontario. Throughout the growing season, particularly July and August, ozone levels vary significantly.

Periods of high ozone are associated with regional southerly air flows that are carried across the lower Great Lakes after passing over many urban and industrialised areas of the United States. Localized, domestic ozone levels also contribute to the already high background levels. Injury levels vary annually and white bean, which are particularly sensitive, are often used as an indicator of damage. Other sensitive species include cucumber, grape, green bean, lettuce, onion, potato, radish, rutabagas, spinach, sweet corn, tobacco and tomato.

Resistant species include endive, pear and apricot. Ozone symptoms Figure 1 characteristically occur on the upper surface of affected leaves and appear as a flecking, bronzing or bleaching of the leaf tissues. Although yield reductions are usually with visible foliar injury, crop loss can also occur without any sign of pollutant stress.

Conversely, some crops can sustain visible foliar injury without any adverse effect on yield. Susceptibility to ozone injury is influenced by many environmental and plant growth factors. High relative humidity, optimum soil-nitrogen levels and water availability increase susceptibility. Injury development on broad leaves also is influenced by the stage of maturity. The youngest leaves are resistant. Cotton crops show significantly less yield when exposed to levels of ozone in the atmosphere.

Common symptoms of ozone pollution are yellowing, flecking and blotching in leaves, premature senescence and early maturity. It interferes with pollen formation, pollination, pollen germination and growth of pollen tubes. Increase in the level of RNA, starch, polysaccharides and number of polysomes is observed in ozone pollution. Ozone stimulates respiration, inhibits oxidative phosphorylation and changes membrane permeability. In some species, it inhibits the synthesis of glucon and cellulose and reduces the level of reducing sugars, ascorbic acid and ATP while in other species the effect is opposite to it.

The impact of ozone on plants increases with humidity and decreases with drought, darkness, low temperature, high soil salinity, deficiency of soil phosphorus and excess of soil sulphur.

Throughout the growing season, particularly July and August, ozone levels vary significantly. Periods of high ozone are associated with regional southerly air flows that are carried across the lower. Localized, domestic ozone levels also contribute to the already high background levels.

Injury levels vary annually and white bean, which are particularly sensitive, are often used as an indicator of damage. Other sensitive species include cucumber, grape, green bean, lettuce, onion, potato, radish, rutabagas, spinach, sweet corn, tobacco and tomato.

Resistant species include endive, pear and apricot. Ozone injuries to soybean foliage [ 26 ]. Ozone symptoms fig. Although yield reductions are usually with visible foliar injury, crop loss can also occur without any sign of pollutant stress.

Conversely, some crops can sustain visible foliar injury without any adverse effect on yield. Susceptibility to ozone injury is influenced by many environmental and plant growth factors. High relative humidity, optimum soil-nitrogen levels and water availability increase susceptibility. Injury development on broad leaves also is influenced by the stage of maturity.

The youngest leaves are resistant. With expansion, they become successively susceptible at middle and basal portions. The leaves become resistant again at complete maturation. Ground-level ozone causes more damage to plants than all other air pollutants combined. This web page describes the ozone pollution situation, shows classical symptoms of ozone injury and shows how ozone affects yield of several major crops. Ozone enters leaves through stomata during normal gas exchange.

As a strong oxidant, ozone or secondary products resulting from oxidation by ozone such as reactive oxygen species causes several types of symptoms including chlorosis and necrosis. It is almost impossible to tell whether foliar chlorosis or necrosis in the field is caused by ozone or normal senescence. Several additional symptom types are commonly associated with ozone exposure, however.

These include flecks tiny light-tan irregular spots less than 1 mm diameter , stipples small darkly pigmented areas approximately mm diameter , bronzing, and reddening. Ozone symptoms usually occur between the veins on the upper leaf surface of older and middle-aged leaves, but may also involve both leaf surfaces bifacial for some species.

The type and severity of injury is dependent on several factors including duration and concentration of ozone exposure, weather conditions and plant genetics. One or all of these symptoms can occur on some species under some conditions, and specific symptoms on one species can differ from symptoms on another.

With continuing daily ozone exposure, classical symptoms stippling, flecking, bronzing, and reddening are gradually obscured by chlorosis and necrosis. Studies in open-top field chambers have repeatedly verified that flecking, stippling, bronzing and reddening on plant leaves are classical responses to ambient levels of ozone. Plants grown in chambers receiving air filtered with activated charcoal CF to reduce ozone concentrations do not develop symptoms that occur on plants grown in non-filtered air NF at ambient ozone concentrations.

Foliar symptoms shown on this web site mainly occurred on plants exposed to ambient concentrations of ozone either in NF chambers or in ambient air. Yield Loss Caused by Ozone. Field research to measure effects of seasonal exposure to ozone on crop yield has been in progress for more than 40 years.

Most of this research utilized open-top field chambers in which growth conditions are similar to outside conditions. At each location, numerous chambers were used to expose plants to ozone treatments spanning the range of concentrations that occur in different areas of the world. The strongest evidence for significant effects of ozone on crop yield comes from NCLAN studies [ 18 ] fig. The results show that dicotyledonous species soybean, cotton and peanut are more sensitive to yield loss caused by ozone than monocot species sorghum, field corn and winter wheat.

Particulate Matter. Particulate matter such as cement dust, magnesium-lime dust and carbon soot deposited on vegetation can inhibit the normal respiration and photosynthesis mechanisms within the leaf. Cement dust may cause chlorosis and death of leaf tissue by the combination of a thick crust and alkaline toxicity produced in wet weather. The dust coating fig. In addition, accumulation of alkaline dusts in the soil can increase soil pH to levels adverse to crop growth.

Effect of ozone on yield of crops [ 18 ]. Cement-dust coating on apple leaves and fruit. The dust had no injurious effect on the foliage, but inhibited the action of a pre-harvest crop spray [ 26 ]. Because the crop plants are mostly annual plants they can not show the long-term effects produced by air pollutants.

Therefore to monitor the effects of air pollution are recommended the trees, the changes in forest structure highlight the harmful effects of different air pollutants. The evident decline of the health state of the forest in Europe since the beginning of the due to the negative impact of air pollution were illustrated by numerous publication from this period see litt. In the efforts to obtain objective and comparable data concerning the health of the European forests were developed a common methodology for the assessment of the forest state under the influence of air pollution.

The poor health status of the forests in Central Europe concerns all the Europe. The pictures of the forests on large area were dominated by tree with defoliated crowns and an increasing rate of the death trees fig Under the umbrella of ICP Forest Programme, were developed and implemented an European network of plots for the assessment of the parameters of the trees crowns condition known as Level I plots.

In comparison with the national grids used by each country the obtained data were relevant for the evaluation of the forest health state at European level. After were put in function the Level II monitoring plots used for the intensive monitoring and collection of comparable data related to the changes in forest ecosystems which are directly connected to specific environment at factors such as atmosphere pollution and acid deposition. Such data can help in a better understanding at the relation causes and effects in the forests decline.

General aspects of silver fir crowns affected by decline in the border of the northern Carpathians Forest District Solca. Fifteen years of monitoring forest condition and two decades of forest damage research have shown, however, that the discussion of recent forest damage must not be confined to the effects of air pollution alone.

The comprehensive monitoring programme corresponds to the complex interrelations between natural and anthropogenic factors in forest ecosystems.

Infrastructure and data of the programme are thought to be relevant for other processes of international forest policies, e. The monitoring results obtained each year are summarized in annual Executive Reports.

Methodology for the crown health condition assessment of forests. The state of health of forest trees can be determined by assessing the foliage loss. With a little practice, this can be accurately estimated by the foresters or other trained personnel.

The development of forest damage can be traced through repeated assessments of the same trees. Loss of needles or leaves should be assessed after sprouting in spring or early summer and before broadleaves and larch display autumn coloration, at best in July and August.

Evergreen conifers fig. Assessments should be made under good light conditions in good weather: rain and fog render assessments inaccurate. Leaf or needle loss is estimated for the entire crown. The crown is considered to reach from the peak of the tree to, the lowest strong green branch forming part of the crown as such; epicormic shoots on the stem are not considered, while those in the crown are.

A forest tree can spread its crown to a greater or lesser extent depending on the room available within the stand. Consequently, spatial conditions must be considered in crown assessment; that is, the maximum foliage that each tree could possibly produce must be taken as a basis.

The photo series fig. It is therefore applicable to trees of the middle and lower strata only to a limited extent. Foliage loss may be determined by comparing the tree under consideration with the corresponding photo series. The appearance of the crown is matched with one of the photos and the foliage loss estimated to a degree of 5 percent accuracy. Assessments should be made with field-glasses from a distance of at least one tree-length.

Field-glasses permit precise identification of bare branches and twigs and discoloration. In subsequent surveys it is important that the tree always be observed from the same side; this should either be marked on the tree itself or noted in terms of compass direction.

Leaf or needle loss due to known causes, e. The draft long-term strategy of WGE specifies the following long-term aims to which all ICP are expected to contribute:.

The present status, long-term trends and dynamics, and the degree and geographical extent of the impact of air pollution, particularly, but not exclusively, its long range trans-boundary impact. Derivation of exposure-response functions for chemical and biological effects of air pollutants including investigation of nutrient nitrogen, acidifying compounds and ozone effects on ecosystem functions and on biodiversity, including combinations with other stresses e.

Further development of models and mapping procedures, particularly for effects of nitrogen and ozone on the environment and for the description of dynamic processes of damage and recovery acidification, eutrophication, heavy metal accumulation by including to a larger extent biological effects;. Objective 1: A periodic overview on the spatial and temporal variation of forest condition in relation to anthropogenic and natural stress factors in particular air pollution by means of European-wide and national large-scale representative monitoring on a systematic network.

Objective 2: A better understanding of the cause-effect relationships between the condition of forest ecosystems and anthropogenic as well as natural stress factors in particular air pollution by means of intensive monitoring on a number of selected permanent observation plots spread over Europe and to study the development of important forest ecosystems in Europe.

These objectives imply in accordance with the long-term priorities of WGE contributions to calculations of critical loads and levels and the assessment of their exceedances.

They imply also dynamic modeling of the response of forest ecosystems to deposition scenarios expected for the future. Additional insight is gained by compiling available studies from the National Focal Centers NFCs and from related programmes inside and outside of Convention on Long-range Trans-boundary Air Pollution.

Monitoring activities. In order to meet its data generation and reporting obligations, ICP Forests employs data collection at two levels. Large-scale monitoring Level I provides a periodic overview of the spatial and temporal variation in a range of attributes related to forest condition.

Level I plots, national forest inventory NFI plots, and other related inventory plots may be combined when appropriate, feasible and necessary, according to defined and agreed procedures. Intensive monitoring Level II is carried out on plots installed in important forest ecosystems. These plots are dedicated to in-depth investigation of the interactive effects of anthropogenic and natural stress factors on the condition of forest ecosystems.

Quality assurance and control. All monitoring activities are harmonized by ICP Forests among the participating countries and are laid down in this Manual. This ensures a standard approach for data collection and evaluation and can form the nucleus for a future common European forest monitoring programme. A consistent quality assurance approach is applied within the programme covering the set up of methods, data collection, submission and investigation as well as reporting.

Quality assurance and control is supervised by the Programme Coordinating Group through its Quality Assurance Committee. A set of Expert Panels cares for data quality assurance within the specific surveys and for the further development of monitoring methods and standards. This includes field checks, inter-calibration courses, laboratory ring tests, and data validation. Data evaluation and reporting.

A range of monitoring variables is required to meet the information requirements of Convention on Long-range Trans-boundary Air Pollution and other international institutions. The Programme Coordinating Group and the Expert Panels are responsible for a data evaluation and reporting approach which takes the medium term work-plan of Working Group on Effects of Atmospheric Pollution into account.

International and national data from other programmes and institutions should be included in combined analysis.

The main topics for data analysis are:. Trends in deposition and their interactive effects on the adaptation and vulnerability of forest ecosystems are evaluated. This includes spatial and temporal changes and cause-effect relationships with special emphasis on critical loads and their exceedances.

Dynamic models and transfer functions derived from suitably selected intensive monitoring plots are used to investigate the effects of climatic factors and greenhouse gases on forest ecosystems and applied to the large scale monitoring plots. These models are validated against measured data collected at the plots. Furthermore, data gathered at the plots are used in an integrated manner to investigate the carbon sequestration potential of forests, ozone fluxes to forests and contribute to assess status and trends of forest biodiversity at the pan-European level.

This facilitates an understanding of the effects of deposition on the role and functioning of forest ecosystems in protecting soils and water. Furthermore the programme surveys can contribute to the understanding and forecast of climate change effects on forests and can be used to supply information on the sequestration of carbon and are going to provide information on forest biodiversity as an integral part of forest ecosystems.

ICP Forests aims to provide periodic overviews on the spatial and temporal variation of forest condition in relation to man-made and natural stress factors particularly air pollution ; to contribute to a better understanding of the cause-effect relationships between the condition of forest ecosystems and man-made and natural stress factors particularly air pollution ; and to study the development of important forest ecosystems in Europe.

More specifically, to support harmonized forest monitoring by linking existing and new monitoring mechanisms at the national, regional and EU level tab.

Surveys and number of plots for Level II monitoring. Conclusions after 25 years of forest monitoring at European level. The system combines an inventory approach with intensive monitoring.

It provides reliable and representative data on forest ecosystem health and vitality and helps to detect responses of forest ecosystems to the changing environment. The data collected so far provide a major input for several international programmes and initiatives, such as the Convention on Long-range Trans-boundary Air Pollution and the Ministerial Conference for the Protection of Forests in Europe.

Forest surveys and defoliation classes for all tree species in European countries Results of national surveys as submitted by National Focal Centres after www. In the early s, a dramatic deterioration in forest condition was observed in Europe and this initiated the implementation of forest condition monitoring under Convention on Long-range Trans-boundary Air Pollution.

Today, the monitoring results indicate that, at the large scale, forest condition has deteriorated far less severely than was feared at that time. Stress factors like insects, fungi and weather effects have been shown to affect tree health. The drought in the Mediterranean region in the mids and the extremely warm and dry summer across large parts of Europe in led to increased levels of defoliation as a natural reaction of trees to this type of stress.

The programme has also reported on acidifying deposition which is regionally correlated with defoliation and on atmospheric inputs that are accentuating other stress factors. In the past three years there has been little change in the mean levels of defoliation for the main European tree species. However, long-term trends show more deterioration than improvement tab.

The health status of forest trees in Europe is monitored over large areas by surveys of tree crown condition. Trees that are fully foliated are regarded as healthy. The Ministerial Conference on the Protection of Forests in Europe uses defoliation as one of four indicators for forest health and vitality. In , crown condition data were submitted for plots in 30 countries.

In total, trees were assessed. In , This represents no change relative to Of the main tree species, European and sessile oak had the highest levels of damaged and dead trees, at There were no significant changes in crown condition over the past ten years on two-thirds of the plots, but deterioration prevailed on the remaining third. Trends vary between species, with European and sessile oak the most frequently damaged species.

However, both have shown some recovery over the past five years. The health of Norway spruce and Scots pine has improved over the past 18 years. Defoliation in common beech, Holm oak and maritime pine has increased. There has been no significant change in tree health on most plots monitored over the past ten years. Defoliation increased on Over the past 18 years there has been a clear improvement in crown condition for Scots pine and a slight improvement for Norway spruce. European and sessile oak have shown the highest mean defoliation over the past decade.

Defoliation peaked after the extremely dry and warm summer in and has been slowly recovering since Defoliation of common beech peaked in , while Holm oak showed a sharp deterioration in crown condition in the mids and again in Unfavorable weather conditions are thought to be responsible for these trends. There was a reasonably consistent increase in defoliation of maritime pine up to , followed by a short period of recovery after which crown condition again deteriorated in [ 28 ], [ 29 ], [ 30 ].

Extent of defoliation for the main European tree species. Total Europe and EU, Defoliation is an indicator of tree health and vitality that can be easily monitored over large areas and which reacts to many different factors, including climatic conditions and weather extremes as well as insect and fungal infestations.

Defoliation represents a valuable early warning system for the response of the forest ecosystems to change — this is particularly relevant as climatic extremes are predicted to occur more frequently in the relatively near future. Deposition of pollutants from the air can affect soil and site conditions and thus the condition of forest trees. The status and trends in forest condition vary regionally and for different species.

Local conditions may differ from the European average. Conclusions concerning the dynamic of atmospheric deposition. Measurements are carried out within the forest stands through fall deposition and in nearby open fields bulk deposition. In the forest canopy, some elements can be leached from the foliage and increase the measured deposition load, whereas others are taken up by leaves and needles and are so not detected in through fall.

Bulk deposition is mostly lower than through fall deposition because of the additional deposition loads filtered from the air by the forest canopy. Thus, neither through fall deposition nor bulk deposition is equal to the total deposition received by the forest stands. However, through fall deposition is presented here as this reflects the inputs reaching the forest floor and so these measurements are of greater ecological relevance to forest ecosystems than open field measurements.

On the plots, samples are collected weekly, fortnightly or monthly and are analyzed by national experts. After intensive quality checks, annual mean deposition for the years to was calculated for plots with complete data sets. Slopes of plot wise linear regressions of deposition over time were tested for significance. Plot-specific means were calculated for the period to These findings are based on deposition measurements made under the forest canopy on plots located mostly in central Europe.

Mean nitrogen inputs showed little change or only a very small decrease. The downward trend in sulphur deposition reflects the success of the clean air policies under the UNECE and the EU for sulphur emissions. In contrast, the nitrogen deposition data indicate a clear need for further reductions in nitrogen emissions. Deposition is generally higher on central European plots than on plots in northern and southern Europe. On average, through fall deposition in forests is higher than deposition on open field sites because trees filter dust and other dry deposition from the air which is then washed from the foliage to the forest floor by rain.

About half the plots showed a significant reduction in sulphur inputs over the year study period. The data are mean values from around measurement stations located mainly in central Europe. Mean nitrogen deposition within the forest stands fluctuated for nitrogen measured as nitrate and ammonium and few plots showed significant changes in through fall deposition.

Slight decreases in mean nitrogen deposition at the open field plots were observed fig. The deposition data show the success of the clean air policies in Europe for sulphur emissions, and show the need for further reductions in nitrogen emissions [ 31 ], [ 32 ], [ 33 ].

Development of mean deposition of sulphate from to The forest canopy alters pollutants from the air. Inputs within the forest stands are higher than in the open field. In there was less precipitation and thus less deposition. Development of mean plot deposition of nitrogen compounds plots from to Some reduction are visible in open field measurements. There was little change in deposition for the forest stands over the10 years of observation.

Atmospheric deposition has been the specific focus of the programme since its inception. However, critical limits in the soil water are still substantially exceeded on a quarter of the plots and indicate a potential threat to forest vegetation. Earlier studies conducted under the programme have shown that the risk of storm damage is higher on acidic soils. Nitrogen inputs have hardly changed over the past ten years and the data sets now show shifts in the composition of forest ground vegetation towards more nitrogen tolerant species.

Atmospheric deposition is a driver for these changes in biodiversity. Another effect of nitrogen deposition is increased tree growth which was found on intensive monitoring plots across Europe [ 34 ]. Licensee IntechOpen. Help us write another book on this subject and reach those readers. Login to your personal dashboard for more detailed statistics on your publications. Edited by Mohamed Khallaf.

Edited by Nicolas Mazzeo. We are IntechOpen, the world's leading publisher of Open Access books. Built by scientists, for scientists. Our readership spans scientists, professors, researchers, librarians, and students, as well as business professionals. Downloaded: Introduction The main air pollutants are represented by gases forms, particles in suspension, different ionizing radiation and noise.

Name of pollutants Origin Effects Natural sources sulfur, chlorine, and ash particulates, smoke and carbon monoxide methane volatile organic compounds VOCs Aerosol from deforestation and burning: CO, CO 2 , NO, NO 2 , N 2 O, NH 4 Volcanoes, wildfires, cattle and other animals, pine trees - acid rain, - smog, - respiratory irritant - increased respiratory - diseases - damage cell membranes of plants The effects are high only for volcanoes.

Anthropic sources Carbon monoxide, carbon dioxide, sulphur dioxide, nitrogen oxides, fluorides and substances with fluorine, chlorine Cl 2 , bromine Br 2 and iodine I 2 , small dust particles, VOC, methane, ammonia and radioactive radiation. Industry: the mining industry, oil and natural gas extraction, the energy industry based on fossil fuels - coal, oil, natural gas, the production of brick, tile, enamel frit, ceramics, and glass; the manufacture of aluminium and steel; and the production of hydrofluoric acid, phosphate chemicals and fertilizers.

Table 1. Type of pollutants, origin and effect at global level or on plants end animals individuals. Minor gaseous pollutants Hydrogen sulphide H 2 S Plants show wilting on exposure to this gas but the symptoms develop after about 48 hours. Carbon monoxide CO Like ethylene this gas produces epinasty, chlorosis and abscission.

Bromine Br 2 and Iodine I 2 Studies show these gases are highly toxic to plants. Mercury vapors Hg Unlike other pollutants, flowers are more sensitive to Hg than leaves. Particulate pollutants Different types of solid particulate materials are also important air pollutants.

Cement-kiln dust In generals, plants having hairy surface of leaves trap more dust and are, therefore, damaged more than the plants with shiny leaf surface. Lime and gypsum Lime and gypsum deposited on the soil from the air, these change the pH of the soil and thus affect the nutrient availability to plants. Soot Soot deposited on the surface of leaves may be washed away by rains so its damage may be reduced.

Magnesium oxide Deposited on the soil these compounds can soon increase the soil pH to levels injurious to plants. Boron Severe injury to plants is observed even at a distance of meters from the source and mild injury may be observed up to meters in all the directions from the source.

Pesticides, insecticides and herbicides A large variety of such chemicals are sprayed on the crops these days. Secondary pollutants and plants Many of the primary pollutants under specific environmental conditions may interact with each other and produce secondary environmental pollutants or certain complex environmental conditions that are injurious to plants. Effect of atmospheric pollutants on vegetation monitoring system, why forestry monitoring system?

Quality assurance and control All monitoring activities are harmonized by ICP Forests among the participating countries and are laid down in this Manual. Data evaluation and reporting A range of monitoring variables is required to meet the information requirements of Convention on Long-range Trans-boundary Air Pollution and other international institutions. The main topics for data analysis are: Forest condition Effects on forest ecosystems from Acidity and nitrogen Ozone Contributions in the fields of Climate change Biodiversity Trends in deposition and their interactive effects on the adaptation and vulnerability of forest ecosystems are evaluated.

Survey Number of plots Assessment frequency installed Data submitted for Crown condition Annually Foliar chemistry Every two years Soil condition 0 Every ten years Soil solution chemistry Continuously Tree growth 70 Every five years Deposition Continuously Ambient air quality active 84 27 Continuously Ambient air quality passive Continuously Ozone induced injury 43 Annually Meteorology Continuously Phenology 58 Several times per year Ground vegetation 67 Every five years Litterfall Continuously Remote sensing National data Preferably at plot installation.

Table 2. Table 3. More Print chapter. How to cite and reference Link to this chapter Copy to clipboard. Available from:. Over 21, IntechOpen readers like this topic Help us write another book on this subject and reach those readers Suggest a book topic Books open for submissions.

More statistics for editors and authors Login to your personal dashboard for more detailed statistics on your publications.

Access personal reporting. More About Us. Name of pollutants. Natural sources. Volcanoes, wildfires, cattle and other animals, pine trees. Anthropic sources. Carbon monoxide, carbon dioxide, sulphur dioxide, nitrogen oxides, fluorides and substances with fluorine, chlorine Cl 2 , bromine Br 2 and iodine I 2 , small dust particles, VOC, methane, ammonia and radioactive radiation. Agriculture: the vegetation fire, the denitrification process, in soils excessively fertilized and excessive use the pesticides , paddy field, intensive husbandry, deforestation.

The motor vehicle pollution, noises. Number of plots. Assessment frequency. Data submitted for Crown condition. Foliar chemistry. Every two years. Soil condition. Every ten years. Soil solution chemistry. Tree growth.

Every five years. Ambient air quality active. Ambient air quality passive. Ozone induced injury. Several times per year. Ground vegetation. Remote sensing. National data. Preferably at plot installation. Participating countries.