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INDIGENOUS AND CULTIVATED PLANTS AS BIOINDICATORS
Leonard H. Weinstein John A. Laurence
Boyce Thompson Institute
Ithaca, NY 14853
ABSTRACT
In most geographical regions, indigenous or cultivated species
of plants are present for use as indicators of pollution from
ozone, sulfur dioxide, hydrogen fluoride, hydrochloric acid,
chlorine, and other phytotoxicants. Where they do not occur,
portable "gardens" or lichen "boards" can be distributed in
appropriate areas, or gardens can be planted in situ Careful
selection of indicator species can not only identify the pollutant
or pollutant mixture, but can provide approximate estimates of
geographic distribution, source strength, pollutant dose, and can
aid in locating particular sources. A useful adjunct is
measurement of pollutant accumulation by chemical analyses,
especially for metals and fluoride. Evaluations are made by: (a)
Studies of species depletion, such as lichen deserts. (b) specific
types of foliar lesions and field distribution of sensitive species.
Plant bioindicators are low in cost and maintenance, and are
applicable to urban and rural areas, to wide geographical areas,
and to remote areas where electrical power is unavailable.
INTRODUCTION
Plant bioindicators or biomonitors are living entities that respond, usually at the
organismal level, in characteristic and reliable ways to physical or chemical factors in
their environment. The occurrence, distribution, vigor, and appearance of indigenous or
cultivated plants, or their capacity to accumulate toxicants, have been used for more
than 75 years to detect the presence and amount of airborne pollutants (44~.
Plants range in sensitivity to airborne pollutants from highly sensitive to highly
tolerant. Often there is significant range in sensitivity between cultivars of the same
species. In ecosystems, plants are often the most susceptible receptors of toxicants, and
their response, whether in the production of foliar lesions, change in form, or altered
metabolism, may be more easily measured than chemical or physical detection of
pollutants.
Generally, by the response of one or more bioindicators/biomonitors can help to
identify ecological problems, to document changes and trends in the general quality of
forest ecosystems, and to predict effects on wildlife habitats. Specifically, they have
been used to (i) establish the presence of a pollutant, (ii) aid in its identification, (iii)
relate dose of the pollutant to response of the receptor, (iv) delineate the spatial and
temporal distribution of the pollutant, and (v) measure pollutant accumulation (gases,
particles, heavy metals, etc.~. Since the general methods of using plant receptors were
first introduced, many different approaches have been used for each type or species and
195
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many of these will be reviewed briefly. The minor differences in the methods used to
biomonitor forest, agricultural, or urban ecosystems, will not be discussed.
Plant bioindicators can be compared to the use of litmus paper to indicate that a
substance is acidic. However, little quantitative information, except perhaps the identity
of the toxicant through the production of specific symptoms, is provided. Plant
biomonitors, on the other hand, may provide a quantitative estimate of the amount of a
toxicant accumulated by a selected species, as a pH electrode quantitates acidity. Under
appropriate conditions, biomonitors can substitute for instruments, and they have the
advantage that, unlike instruments, they integrate the effects of the toxicants over a
range of environments (20, 2S, 39, 52~. Thus, in this context, they are biointegrators,
expressing the biological effect of a dose of pollutant and integrating climatic, cultural,
and other biological factors into their response. In some cases, bioindicators and
biomonitors may substitute for mechanical collectors or analytical instruments, especially
where access to utilities is limited. In addition, biomonitoring programs may be less
costly than physical or chemical systems. In other cases, however, the use of receptor
organisms may be preferred, since they are "tuned" to the ecosystem and will respond to
climatic changes taking place. The State of Maryland has chosen to include plant
biomonitoring, by assessing foliar fluoride concentration, in its standard to evaluate
effects of fluorides on plants.
GENERAL CONSIDERATIONS
To an ecologist, a bioindicator is a species of plant or animal that responds
characteristically to the conditions that occur in a particular region or habitat (31~. In
air pollution studies, it is used to define a plant which exhibits a specific symptomology
when exposed to a phytotoxicant (14, 15~.
The useful bioindicator is a plant that is (a) genetically uniform to minimize natural
variability (14, 15~; (b) sensitive to a specific pollutant by producing a characteristic and
easily recognizable symptom; (c) abundant and with a large geographical distribution (13~;
(~) capable of growth throughout the field season (19~; and (e) capable of absorbing a
pollutant in a predictable manner if it is to be used as a measure of accumulation (14,
15, 17~.
Selection of Plant Materials
Lists of plant species exhibiting varying degrees of sensitivity to air pollution have
been catalogued (3, 4, 5, 7, 14, 15, 24, 25, 26, 29, 34, 49, 50, 51, 54, 55~. In general,
those sensitive species with the widest distribution in an area of concern are the
preferred bioindicators (12~. If the purpose of a survey is to determine a simple "yes" or
"no" answer that one or more pollutants are causing a problem, all sensitive vegetation
should be inspected regardless of species. If the purpose of the survey is to provide
information for mapping, for example, based upon the degree of injury observed, a single,
widely distributed species should be used. Often, lower forms of plant life are employed,
including mosses and lichens. These lower forms may not only be widely distributed but
they may also have other attributes, such as extreme sensitivity to the pollutantts), e.g.,
lichens and sulfur dioxide ant! fluoride. One major drawback to the use of lichens is
that they are very slow-growing and severe damage or destruction can eliminate them
from an ecosystem. But the absence of lichens in a particular area is also valuable
information, and the lichen "deserts" in cities and around certain industrial sources are
well known (27, 2S, 41~. If there are no sensitive indigenous species present, surrogate
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species may be introduced at selected sites. Where a single pollutant is known or
suspected to be responsible for an ecological problem, only a single species may be
needed. Where the problem might be caused by more than one pollutant, an array of
species is selected and distributed in key sites.
Indicator Species
Indicator plant species may be used to detect and evaluate all important
ecotoxicants by exhibiting extreme sensitivity, e.g., the production of characteristic
symptoms in the form of necrotic or chlorotic lesions, distortion of plant growth or
other changes in form, alterations in pigment development, or the capacity for
accumulation. It is rare that the indigenous or cultivated species in an area do not
include some suitable bioindicators in agricultural or forest ecosystems. It is often
possible to use a dominant crop or tree species as the principal bioindicator. For
example, white pine shows great sensitivity to ozone and sulfur dioxide, and the
symptoms are different (23~. In Ontario, silver maple is used as a biomonitor through
accumulation of airborne fluoride, where measured values above a given concentration in
the foliage indicate a polluted condition. If one or more native species are not available,
introduced species may be used. Outstanding examples are the use of gladiolus plants as
an indicator of fluoride pollution (54, 55), or of Bel-W3 tobacco (21, 22) and Japanese
morning glory as indicators of photochemical oxidant pollution (32, 38~. Many species of
mosses and lichens are used to evaluate air purity (16, IS, 33, 35, 36, 37, 42, 43, 48) or
accumulation of heavy metals (11, 41~. White ash, wild cherry, yellow poplar, and many
other deciduous trees are sensitive to ozone; birch, beech, catalpa, and many maples are
examples of trees sensitive to sulfur dioxide; most pines, boxelder, apricot, peach, and
many other deciduous and coniferous tree species are sensitive to fluoride. Goldenrods, a
widely distributed indigenous weed, are excellent accumulators of PCBs (10~.
Kinds of Symptoms
The most common characteristic of an indicator species is the production of foliar
lesions in response to a given pollutant. Measurements of injury can be very simple,
e.g., injured vs. non-injured, or more complex, e.g., assignment of subjective or objective
numerical values to denote severity. Additional variables used to assess the effects of
pollutants have included percentage of leaves injured, percentage of leaf area injured,
growth in length, fresh mass, dry mass, photosynthesis, respiration, transpiration, or
chlorophyll content (19, 40~.
Plants are also used as accumulators of specific toxicants and many of these
systems are in use throughout the world to measure fluorine, sulfur, heavy metals, PCBs,
etc. (17, 19, 30, 40, 41~. The presence or absence of certain characteristic traits or
diseases can also be used. For example, the relative abundance of tarspot of maple (6)
or blackspot of rose (45), both diseases caused by fungi, have been used to judge air
quality.
Field Monitoring Systems
Several field biomonitoring systems have been developed and deployed. Several are
described below.
Indicator Gardens - Perhaps the simplest system is the indicator garden, consisting of
species of plants that respond differentially to pollutants (3, 14, 15, 40, 53~. Such a
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bioindicator garden is in use in Minnesota to monitor sulfur dioxide and ozone
concentrations ( 1 ) (Fig. 1~. Indicator gardens are grown in indigenous soil or in a soil
mixture of known composition and they utilize species of known and defined sensitivity.
For instance, genetic isolines of tobacco, which differ in their sensitivity to ozone, have
been used. By comparing the slopes of injury (size of foliar lesions) vs. time curves for
line Bel-W3 (sensitive) to line Bel-B (tolerant), air quality can be categorized as poor,
moderate, fair, or good (15~.
Ouaking Aspen .
1.4 m-
.3 m-
1~1
_1 1
I I
1 1 ~ 1
1 1 1~
=~
.112131Bl2ll all I I
AItelte-Vernal
/ ~
1 —Ragweed
2 Batchelore Buttons
3—Milkweed
E
cat
u)
~ Transportable
Trays
Replaced 8011
Figure 1. Bioindicator plot design used in Minnesota to monitor ozone and sulfur
dioxide.
Portable Exposure Benches-
· , ,
Often locations where bioindicators are used are isolated,
maintenance Watering, weeding, fertilizing, etc.) becomes a concern. This problem is
partly solved by the use of special growth benches (2, 3~. These benches not only
support potted indicator plants above the ground for protection from animals, but also
provide an automatic watering system (Fig. 2~. Exposure benches are used extensively
in Europe for supporting indicator trees or other sensitive species.
Lichen Transplants- Disks of corticolous lichen thalli with their bark substrate have
been transplanted from areas of clean air to trees growing in polluted air (S. 9~. A more
successful system, where lichen disks are placed in holes in boards and mounted on posts,
is in use in Germany. Lichens may also be transplanted to small blocks of wood that are
attached to the vanes of an anemometer, thus insuring continuous exposure of the lichen
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199
transplant to the prevailing winds (3, 41, 47~. One disadvantage of using lichens is that
they respond slowly to changes in air quality and seldom recover once damaged severely.
_1 -
!
14q~
~5
ne'"
,,,
it,
At,
an,;
.~
, \,, - .
I,
/1~/'
,=7~,,
l
I ~
,,,
~ To,
do
,'
At'
Few ~ ~
Ad,
~1
Figure 2. Exposure bench for multiple bioindicator plants, supported by a galvanized steel frame
and with automatic watering. The water reservoir, Styrofoam support, and potted plant are shown.
Source: Resprinted with permission of Staub-Reinh from Luft 1985. Copyright 1985 by Staub-
Reinh.
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200
Grass Cultures- Standard methods have been devised for determinating the accumulation
of several air pollutants over short- and long-term periods using ryegrass cultures (3, 46)
(Fig. 3~. The methods are primarily used in Germany for monitoring fluoride, sulfur,
chloride, lead, cadmium, zinc, copper, nickel, vanadium, and other elements. In general,
the cultures consist of seedlings of ryegrass growing in a defined medium, provided with
a water supply, and mounted above the ground. By removing samples at specific
intervals for elemental analysis, the rate of uptake, geographical distribution, and total
accumulation of toxicant can be determined.
5
Figure 3. Self-watering grass culture containers for biomonitoring of heavy metals,
fluoride, etc. Left: (1) standard soil mix, (2) ceramic cylinder, (3) filter plate, (4) wick,
(5) water reservoir, (6) overflow hole, (7) double-walled container, (~) connector flange.
Right: ( 1 ~ standard soil mix, (2) glass fiber wick, (3) water reservoir, )4) overflow hole,
(5) outer container, (6) connector flange.
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201
Conclusions - Biomonitor systems can be attractive alternatives to the usual physical-chemical
methods for detecting and measuring air pollutants. The success of biomonitor programs is
dependent on the geographic area where they are used, and the amount of research devoted to
developing and calibrating the system. Biomonitors have some advantages over more traditional
monitoring systems. They are biointegrators, expressing the biological effects of the dose of
pollutant. They are generally low cost and low maintenance systems, applicable to urban and rural
areas, to wide geographical areas, and to remote forest ecosystems. They are, perhaps, the best early
warning systems available.
REFERENCES
2.
3.
5.
Anonymous. 1984. Development of a Biological Air Quality Indexing System. A Report
to the Minnesota Air Quality Board. 380 pp. St. Paul, MN 55101.
Arndt, U., Erhardt, W., Keitel, A., Michenfelder, K., Nobel, W., and C. Schluter. 1985.
Standardisierte Exposition van pflanzlichen Reaktionsindikatoren. Staub-Reinh. Luft
45:481 -483.
Arndt, U., Nobel, W., and B. Schweizer. 1987. Bioindikatoren. Moglichtkeiten, Grenzen
und neue Erkenntnisse. 388 pp. Eugen Ulmer GmbH & Co., Stuttgart, FRG.
Benedict, H.M., and W.H. Breen. 1955. The use of weeds as a means of evaluating
vegetation damage caused by air pollution. Proc. Natl. Air Pollution Symp., 3rd, pp. 177-
190.
Berge, H. 1973. Plants as indicators of air pollution. Toxicology 1:79-89.
6. Bevan, R.J., and G.N. Greenhalgh. 1976. Rhytissma acerinum as a biological indicator of
air pollution. Environ. Pollut. 10:271 -285.
Brandt, C.S., and W.W. Heck. 1968. Use of plants for pollutant identification and field
monitoring. Pp. 428-443 in A.C. Stern, (ed.), Air Pollution, Vol. 1, 2nd ed. Academic
Press, New York.
Brodo, I.M. 1961. Transplant experiments with corticolous lichens using a new technique.
Ecology 42:838-841.
9. Brodo, I.M. 1966. Lichen growth and cities: A study on Long Island, New York.
Bryologist 69:427-449.
10. Buckley, E. H. 1987. PCBs in the atmosphere and their accumulation in foliage and crops.
Chapter 7. Pp. 175-201 in Phytochemical Effects of Environmental Compounds, J.A.
Saunders, L. Kosak-Channing, and E. Conn (eds.~. Plenum Publ. Corp.
Clough, W.S. 1975. The deposition of particles on moss and grass surfaces. Atmos.
Environ. 9:1113-1119.
12. Cole, G.A. 1958. Air pollution with relation to agronomic crops. III. Vegetation survey
methods in air pollution studies. Agron. J. 50:553-555.
OCR for page 202
202
13. Darley, E.F. 1960. Use of plants for air pollution monitoring. J. Air Pollut.
Control Assoc. 10: 198- 199.
14. Feder, W.A. 1978. Plants as bioassay systems for monitoring atmospheric
pollutants. Environ. Health Perspect. 27:139- 147.
15. Feder, W.A., and W.J. Manning. 1979. Living plants as indicators and monitors. In
W.W. Heck, S.V. Krupa, and S.N. Linzon, Handbook of Methodology for the
Assessment of Air Pollution Effects on Vegetation. TE-2 Agricultural Committee,
Air Pollution Control Association, Pittsburgh, PA.
16. Gilbert, O.L. 1968. Bryophytes as indicators of air pollution in the Tyne Valley.
New Phytol. 67:15-30.
17. Guderian, R. 1977. Air pollution: Phytotoxicity of acidic gases and its significance
in air pollution control. Chapter 4 in Ecological Studies, Vol. 22, Springer-Verlag,
Berlin.
18. Hawksworth, D.L., and F. Rose. 1971. Lichens as litmus for air pollution: A
historical review. Int. J. Environ. Stud. 1:281-296.
19. Heck, W.W. 1966. The use of plants as indicators of air pollution. Air Water
Pollut. 10:99- 111.
Heck, W.W., Dunning, J.A., and I.J. Hindawi. 1966. Ozone: Nonlinear relation of
dose and injury in plants. Science 151:577-578.
21. Heck, W.W., and A.S. Heagle. 1970. Measurement of photochemical air
pollution with a sensitive monitoring plant. J. Air Pollut. Control Assoc. 20:97-99.
22. Heggestad, H.E., and H.A. Menser. 1962. Leaf spot-sensitive tobacco strain
Bel-W3, a biological indicator of the air pollutant ozone. Phytopathol. 52:735.
23. Hepting, G.H. 1966. Air pollution impacts to some important species of pine. J.
Air Pollut. Control Assoc. 16:63-65.
24. Hindawi, I.J. 1968. Injury by sulfur dioxide, hydrogen fluoride, and
chlorine as observed and reflected in vegetation in the field. I. Air Pollut. Control
Assoc. 1 S:307-312.
25. Jacobson, J.S. 1977. Plants as indicators of photochemical oxidants in the U.S.A.
VDI-Berichte Nr. 270:191-196.
26. Jacobson, J.S., and A.C. Hill. (eds.) 1970. Recognition of Air Pollut;ion Injury to
Vegetation: A Pictorial Atlas. Air Pollution Control Association, Pittsburgh, PA.
102 pp.
27. LeBlanc, F. 1969. Epiphytes and air pollution. Pp. 211-221 in Air Pollution, Proc.
First European Congress on the Influence of Air Pollution on Plants and Animals,
Wageningen, 1968.
OCR for page 203
203
28. LeBlanc, F., and J. DeSloover. 1970. Relation between industrialization and the
distribution and growth of epiphytic lichens and mosses in Montreal. Can. J. Bot.
48: 1485- 1496.
29. Leone, I.A., Brennan, E., and R.H. Daines. 1964.
indicators. Proc. Northeast. Weed Control Conf. 18:451-457.
Plant life as air pollution
30. Lihnell, D. 1969. Sulphate contents of tree leaves as an indicator of SO2 air
pollution in industrial areas. Pp. 341-352 in Air Pollution.
31. Mellanby, K. 1978. Biological methods of environmental monitoring. Pp. 1-13 in J.
Lenihan and W.W. Fletcher, eds. Environment and Man, Vol. 7: Measuring and
Monitoring the Environment. Academic Press, New York.
32. Nakamura, H., and S. Matsunaka. 1974.
Indicator plants for air pollutants.
Susceptibility of morning glory to photochemical oxidants: Varietal difference and
effect of environmental factors. Proc. Crop Sci. Soc. Jpn. 43:522.
33. Nash, T.H., III. 1973. Sensitivity of lichens to sulfur dioxide. Bryologist 76:333-
339.
34. Nash, T.H., III. 1976. Lichens as indicators of air pollution. Naturwiss. 63:364-367.
35. Nash, T.H., III, and E.H. Nash. 1974. Sensitivity of mosses to sulfur dioxide.
Oecologia 17:257-263.
36. Nash, T.H., III, and L.L. Sigal. 1980. Sensitivity of lichens to air pollution with an
emphasis on oxidant air pollutants. Pp. 117- 124 in Proc. Symp. on Effects of Air
Pollutants on Mediterranean and Temperate Forest Ecosystems. June 22-27, 1980,
Riverside, CA.
37. Nash, T.H., III, and L. Sigal. 1981. Ecological approaches to the use of lichenized
fungi as indicators of air pollution. Chapter 25. Pp. 481 -497 in The Fungal
Community. D.T. Wicklow and G.C. Carrol, eds. Marcel Decker, Inc., New York.,
38. Nouchi, I., and K. Aoki. 1979. Morning glory as a photochemical oxidant indicator.
Environ. Pollut. 18:289-303.
39. Oshima, R.J. 1974. A viable system of biological indicators for monitoring air
pollutants. J. Air Pollut. Control Assoc. 24:576-578.
40. Posthumus, A.C. 1976. The use of higher plants as indicators for air pollution in
the Netherlands. Proc. Kuopio Meeting on Plant Damages Caused by Air Pollution,
Sci. Pap. Symp.,1976, pp.ll5-120.
41. Puckett, K.J. 1988. Bryophytes and lichens as monitors of metal deposition. In
Assessing Air Quality With Lichens and Bryophytes. T.H. Nash III and V. Wirth,
eds. Bibliographica Lichenographica. Stuttgart, FRG.
Rao, D.N., and F. LeBlanc. 1965. Effect of sulfur dioxide on the lichen alga, with
special reference to chlorophyll. Bryologist 69:69-75.
43. Rao, D.N., and F. LeBlanc. 1967. Influence of an iron-sintering plant on
corticolous epiphytes in Wawa, Ontario. Bryologist 70:141-157.
OCR for page 204
204
44. Ruston, A.G. 1921. The plant as an index of smoke pollution. Ann. Appl. Biol.
7:390-403.
45. Saunders, P.J.W. 1966. The toxicity of sulphur dioxide to Diplocarpon rosae Wolf
causing black spot of roses. Ann. Appl. Biol. 58:103-114.
46. Scholl, G. 1971. Die Immissionsrate van Fluor in Pflanzen als Masstab fur eine
Immissionsbegrenzung. VDI Berichte Nr. 164. pp. 39-45.
47. Schonbeck, H. 1969. A method for determining the biological effects of air
pollution by transplanted lichens. Staub-Reinh. Luft 29:17-21.
48. Showman, R.E. 1975. Lichens as indicators of air quality around a coal-fired power
generating plant. Bryologist 78:1-6.
49. Skye, E. 1979. Lichens as biological indicators of air pollution. Annul Rev.
Phytopathol. 17:325-341.
50. Thomas, M.D. 1951. Gas damage to plants. Annul Rev. Plant Physiology 2:293-322.
51. Thomas, M.D. 1961. Effects of air pollution on plants. Pp. 233-278 in Air
Pollution. World Health Organization Monograph Series #46. Columbia University
Press, New York.
52. Treshow, M. 1965. Evaluation of vegetation injury as an air pollution criterion. J.
Air Pollut. Control Assoc. 15:266-269.
53. van Raay, A. 1969. The use of indicator plants to estimate air pollution by SO2
and HF. Pp. 319-335 in Air Pollution. Proc. First European Congr. on the
Influence of Air Pollution on Plants and Animals, Wageningen, 1968.
54. Weinstein, L.H. 1977. Fluoride and plant life. J. Occup. Med. 19:49-78.
55. Zimmerman, P.W., and A.E. Hitchcock. 1956. Susceptibility of plants to
hydrofluoric acid and sulfur dioxide gases. Contrib. Boyce Thompson Inst. 18:263-
279.
Representative terms from entire chapter:
air pollutants
