The Effect of Pure and Mixed Plantations of Robinia ... · PDF fileThe Effect of Pure and Mixed Plantations of Robinia Pseudoacasia and Pinus ... Chitgar forest park of ... making

INTERNATIONAL JOURNAL OF ENVIRONMENTAL SCIENCES Volume 1, No 2 ,2010

© Copyright 2010 All rights reserved Integrated Publishing services

Research article ISSN 0976 – 4402

213

The Effect of Pure and Mixed Plantations of Robinia Pseudoacasia and Pinus Eldarica on Traffic Noise Decrease

Maleki K 1 , Hosseini S. M 1 , Nasiri P

2

1 Department of Forestry, Faculty of Natural Resources, Tarbiat Modares University, Nour, Mazandaran, P.O. Box 46414356, IRAN

2 School of Public Health,Institute of Public Health Researches, Tehran University of Medical Sciences, Tehran, Iran [email protected]

ABSTRACT

This research was conducted to determine the effect of three different plantation types including pure and mixed plantations of Robinia pseudoacasia and Pinus eldarica on noise pollution reduction in Chitgar forest park of Tehran. A point source of noise was positioned in front of each plantation type and the noise level at different distances was measured with a noise meter. Noise values were taken at four measurement points; open area as control treatment (without trees), the urban forests of pure stands of Pinus eldarica and Robinia pseudoacasia and mixed stand and at 7 various distances (10, 20, 30, 40, 50, 75,100m from the noise source, behind tree stands) and 5 repetitions. Among the measured points, mixed stands had the best effect on noise pollution reduction which was about 16.91 dB (A) (decibel) in the distance of 100 meters and up to the permitted level. Noise level reduction was 15.77 dB (A) 50 meter away from noise source within the same stand. Regarding to the negligible difference between the noise reduction effectiveness of these two distances and some limitations to develop urban forests, the tree belts with 50 meters width is recommended to reduce the noise pollution to its standard size.

Keywords: Noise Pollution, Forest Park, Robinia pseudoacasia, Pinus eldarica, Mixed Plantation.1.

1. Introduction

Environmental noise is a worldwide problem. However, the way the problem is dealt with differs immensely from country to country and is very much dependent on culture, economy and politics. But the problem persists even in areas where extensive resources have been used for regulating, assessing and damping noise sources or for creation of noise barriers. For example, huge efforts have been made to reduce traffic noise at source. In fact, today’s cars are much quieter than those manufactured ten years ago, but the traffic volume has increased so much that the effect of this effort has been wiped out and the annoyance level has increased. Compared with other environmental problems noise pollution is still growing high and it has provoked public's complaints (European Report, 1996). After air and water pollution noise in metropolises is considered as the third most serious kind of pollution by the World Health Organization (Khilman, 2004). Ordinarily noise pollution in urban areas is being generated through different sources such as road traffics, construction and commercial activities, industries, airports and residential regions (Macdonald 1977).

Noise affects the human health unfavorably both physically and psychologically (Butcha and Vos 1998, Kura et al 1999, Ali and Tamura 2003, Stansfeld and Matheson 2003). The results of Babisch’s studies indicated that each person has just the capacity to endure a certain dose of traffic noise during his/her lifetime (Babisch et al 2005). Robert Koch in 19th century claimed that the most problem




214

which mankind would face it in future is not infectious diseases but it is noise pollution (Cowans, 1994).

Hence there are many studies which have been done to discover different ways for noise pollution abetment all over the world and then chousing the best of them (Arana and Garcia 1998; Onuu 2000; Zannin et al 2002; Li et al. 2002; Morillas et al. 2002; Sutton, 2003) noise reduction with plants in the urban ecosystems is of great importance (Eyring 1946; Lorenz 1975; Burns 1979; Huddart 1990; Çepel 1994; Rao et al. 2004; Fang and Ling 2005). There are so many reasons to believe that the stresses of noise pollution and unwanted voices (Canneli 1974; Elshorbagy 1984; Garcia and Faus 1991; Bogo et al 2001; Barrigon Morillas et al 2002; Calixto et al., 2003) could be reduced through peace places establishment such as forest parks in urban areas (Grahn et al 2005). This urban forestry and green urban areas play a notable role in the environmental conditions and public life improvement especially on noise pollution reduction (Skarback 2007). The aim of this study is to investigate the effect of three different plantation types on noise pollution reduction in Chitgar forest park of Tehran. These plantations are pure stands of Pinus eldarica and Robinia pseudoacasia and mixed stand of two mentioned species with other species (mainly hardwoods) which are the most common species used for urban forest plantations in Tehran.

2. Materials and methods

2.1 Study area The study area is located in west of Tehran in the Chitgar forest park with an area about 900 hectares between 51° 15´ and 51° 10´ eastern longitude and 35° 42´ and 35° 45´ northern latitude. The figure (1) presents the location of study area. This park has been established in 1968 with some special aims such as air pollution reduction, making a green belt around Tehran, softening the air, making entertainment center and preventing the unsuitable development of city. The trees of park can be divided into three major types including pure hardwood stands, pure softwood stands and mixed stands. Their density is about 800 trees per hectare. 23% of total area of park is covered with Robinia pseudoacasia and 45% of total area is occupied by Pinus eldarica. The trees plantation lines are 1.82m away from each other and the distances between trees in every line is 1.61.8m. These plantations are also even age and about 45 years. The study area is considered as arid Mediterranean climatic region with 1300m elevation above sea level of and mean of annual precipitation is 232mm ( anonymous, 2002).

Figure 1: Image showing the study area

http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6V9W-4H21NF9-1&_user=1399990&_coverDate=10/31/2005&_alid=853991049&_rdoc=13&_fmt=full&_orig=search&_cdi=5909&_sort=d&_docanchor=&view=c&_ct=66&_acct=C000052576&_version=1&_urlVersion=0&_userid=1399990&md5=2814b08c36eec8f4701c61c33d25f98c

http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6V9W-4H21NF9-1&_user=1399990&_coverDate=10/31/2005&_alid=853991049&_rdoc=13&_fmt=full&_orig=search&_cdi=5909&_sort=d&_docanchor=&view=c&_ct=66&_acct=C000052576&_version=1&_urlVersion=0&_userid=1399990&md5=2814b08c36eec8f4701c61c33d25f98c




215

2. Methodology

To investigate the effect of trees on noise pollution reduction, noise values were taken at four measurement points; open area without trees with same topography of other stands as control treatment ( Ozer et al, 2007) , the urban forests of pure stands of Pinus eldarica (fig2) and Robinia pseudoacasia (fig3) and mixed stand (fig4), at seven various distances (10, 20, 30, 40, 50, 75,100m) from the source, behind tree stands and five repetitions in transects within stands and with ten meters distance from each other .

The noise level was measured in mentioned distances with noise meter equipment model 9019 DELTAOHM HD. The heights of noise meter and noise source were the same (Chihfang 2005) and about 1.5 meter over ground. (Jamrah et al 2005; V.Pathak et al 2007). There was no elevation difference between the point source and measurement points at different distances behind tree stands due to flat landform of the study area (Ozer 2007). An amplifier was used as noise source to produce a noise value of 101.5 dB (A) for this study. Whereas the noise source was artificial and under control, at every measurement point five minutes was sufficient to record the noise level. The first measurement was performed in the open area and it was taken as the baseline data for each area (Ozer 2007).

At any point the noise level was first measured beside the noise source and then in seven different distances from noise source at each transect. Noise values were measured in summer, when poplar trees had leaves and at per measurement point the field noise level was noted; generally there were no noise sources at or around the points that might affect the measurements but if disturbing with any wind or other accidental noises, the measurement was repeated in favorable condition. To determine the noise level of the region, the noise of traffics, building constructions, industries, people and etc… were measured beside the road; within 30 minutes (Tyagi et al 2006) and five replications. At every stand the DBH, height and canopy volume of trees were measured in three 10*10 m plots, using selective systematic statistical method.

The SPSS software was used to analyze the data. The normality of taken noise levels were examined with KolmogrovSmirnow test and the homogeny of variances were investigated by Levene test. Attending to the normal distribution and homogeny variances of data Tukey HSD test was used to investigate and compare the noise pollution reduction of these three stands and open area and GLM (General Linear Model) test was applied to examine the interactive effects of various distances and stands. The noise levels which were taken at roadside were compared with Iranian national standard of noise level using one sampleTTest. To draw the diagrams the Excel software was used.




216

Figure 2: The pure stand of Pinus eldarica in study area

Figure 3: The pure stand of Robinia pseudoacasia in study area

Figure 4: The mixed stand in study area

3. Results

In present study the effect of different distances and species were investigated. The main targets of this study were to determine the best species as biological noise barrier and finding a distance which is more effective to reduce the noise level.




217

The taken noise values in different species and their influence on noise abatement were examined. As it is shown in fig (5) in comparison with open area all three stands have acted as noise barriers and the noise level has been reduced behind them. At the 0.05 level (P<0.05) there is a significant mean difference between mixed stands with other stands, but no significant mean difference between pure stands of Robinia pseudoacasia and Pinus eldarica.

Figure 5: The comparison between different stand effect on noise pollution reduction: different letters here show the significant difference between plantations types at the 0.05 level (P<0.05)

The various distances and their effectiveness on noise pollution in mentioned stands are presented in fig (6). Obviously by increasing the distance the noise level decreases. In this study a measurement point with no tree and vegetation with same topography was selected as control in order to define the effect of distance on noise reduction. Comparing with the gained values of other measurement points the most reduction in noise has occurred in mixed stand.

0

30

60

90

120

0 20 40 60 80 100 120

Distance(m)

Noise value(dB(A))

Open

m ixed Stand

Pinus.eldarica

Robinia.pseudoacasia

Figure 6: The effect of distances on noise pollution reduction in different stands.

Figure (7) provides the amount of noise pollution reduction more apparently. The results of this table demonstrate that although distance increment caused the noise abetment but the rate of noise level reduction was not the same and by going 50 meters away from noise source the most increasing rate happened and after this distance as it is clear in Figure (7) the rate of noise level reduction mitigated.




218

The noise reductions of mixed, Pinus eldarica and Robinia pseudoacasia stands at distance of 50meters from noise source were computed 15.77, 13.45 and 12.91 dB (A) respectively. The noise level reduction for mixed stands between 50 and 100 meter is 1.14 dB (A) and it is even less than one dB (A) for Pinus eldarica and Robinia pseudoacasia stands as a result the effect of noise reduction after 50 meter distance could be ignored. Regarding to what were mentioned above, the most noise reduction occurred in mixed stands. About pure stands of Robinia pseudoacasia and Pinus eldarica stands showed more influence on noise level reduction but it is not significant statistically.

6

8

10

12

14

16

18

0 50 100 Distance(m)

Noise re

duction values [d

B(A)]

Mixed Pinus eldarica Robinia pseudoacasia

Figure 7: Noise reduction values (dB(A)) of three stands and the distances(m)

The measured tree parameters (canopy volume, DBH and height) of three considered stands are presented in Figures 8, 9 and 10. As it is seen among them the most canopy volume is related to mixed stands about 2378(m 3 ) per hectare and the least one was calculated for pure Robinia pseudoacasia about 1655(m 3 ) per hectare; Pure Pinus eldarica stand has the biggest DBH of 20.99(cm) and mixed stand has the smallest DBH of 15.87(cm) and about the Height they can be arranged from the most to least according to this order: Pinus eldarica, mixed and Robinia pseudoacasia with the height values of 11.48, 8.05 and 7.9 respectively.




219

Canopy Volume (m3)/Hectare

0

500

1000

1500

2000

2500

Pinus eldarica Robinia pseudoacasia

Mixed

Figure 8: Canopy Volume (m 3 )/Hectare of three different stands

DBH(cm)

0

5

10

15

20

25


Mixed

Figure 9: Diameter at breast height of three different stands

Height (m)

0 2 4 6 8 10 12 14


Mixed

Figure 10: Height of three different stands

The measured field background noise in this study when there was no noise pollution produced by amplifire, at all stands and control area was about 5960 dB and since its diffrence with the selected noise




220

level for this study(101.5 dB (A)) was more than 9dB, the intesity level of field noise was ignored (Stein et al 1986). The study area is located where is being considered as Residentalindustrial region. The noise level of that was determined about 101 dB(A) which is much higher than national noise standards of Iran according to the table(1).

4. Discussion

Noise pollution is an environmental problem of developing cities. Using the different barriers between noise source and the receiver of voice can result in noise reduction trough reflection, refraction, scattering and absorption effects on noise waves (Herrington, 1976; Harris, 1979; Yang and Gun, 2001). These barriers due to conditions can be either Physical or biological barriers or a combination of them. The mounds, hedges and walls are of applicable noise obstructions (Jorge P. Arenas 2008). In this study tree stands of urban Chitgar forest park were considerd as noise barriers. Then their effects on noise attenuation were investigated. As the results of this study indicated comparing with open area three selected stands reduced the noise level behind them. The most noise attenuation occurred in mixed stand which was about 16.91 dB(A) in distance of 100 meters from noise source through the tree stand. The canopy volume for this stand was measured about 2378(m3) per hectare which it was the most among three mentioned stands. so it can be deduced that the more canopy volume and consequently more leaves and branches can play an impotant role to reduce the noise. Density, height, length and width diffuse noise (Cook and Haverbeke, 1974) and the leaf size and branching characteristics have resonant absorption (Aylor, 1972). Leaves have an effictive role to diminish the noise as result mixed stands of various species with a bigger number of leaves are the best stands to reduce the noise( Price et al ,1988). In a study to determine the noise reduction effectiveness of Pinus sylvestris and Populus nigra Ozer and (2007) indicated that as Pinus sylvestris is an evergreen speices with more leaves and higher density have more effectivness than Populus nigra to reduce the noise.

Table 1: The Iranian national noise standard

10AM7AM Leq(30') dB(A)

7AM10PM Leq(30') dB(A) The type of regions

30 50 Residential 50 60 ResidentialCommercial 55 65 Commercial 60 70 ResidentialIndustrial 65 75 Industrial

The results of table (1) showded that although distances caused the noise abetment but the rate of noise level reduction was not the same in different dictances. From the results of this study it can be provided that in three slected stands the best tree belt width in order to reduce the noise is about 50 meters and mixed stand reduced the noise about 15.77dB. Many studies have examined different widths of tree belts and their effect on noise. The tree belts which have more than 30m width can reduce the noise about 48 dB(Eyring 1946; Embleton 1963; Huddart1990; Lercher 1995;Williams and MC Creae1995). Also Kragh (1981) in a study indicated that beech trees with 50m width can reduce the noise level about 89dB more than the regions with are only covered by grass. Maybe the diffrences between suggested tree belts of various studies are because of different tree characters such as crown width, height and density plantation, their branching model and leaves flexibility which are effective to decrease the noise (Bernatzky 1978; Finke 1980; Barner 1983). In order to increase the density plantation it is recomanded to plant shrubs and




221

bushes in under story ( Fang and Ling 2003). It was also found from the ressults of this study that all tree stands could pull the noise value of 101.5 dB(A) far down the permitted noise level of 5565dB(A) where the study area is considerd as residentalindustrial regions. For this, it may be suggested that suitable plantation techniques and plant species must be chosen considering noise reduction effects of the plants in addition to their ecological and aesthetical features (Haverbeke 1971; Erlbeck et al. 1974; Reethof 1973; Booth 1990).

5. Conclusion

From the results of this study it was ditermined that the best biological method to reduce the noise level is the urban plantations of mixed species for the develoing cities like Tehran which are suffering from noise pollution. Also in order to design green areas to have better influence on noise level it is recomanded to use appropriate spieces considering all their chareacters which are suitable for the region echological conditions.

6. References

1. Ali, S. A., & Tamura, A., 2003. Road traffic noise levels, Restrictions and annoyance in greater Cairo, Egypt. Applied Acoustics, 64(8), 815–823.

2. Aylor DE. 1972. Noise reduction by vegetation and ground. J Acoust Soc Am, 51(1):197–205.

3. Arana, M., & Garcia, A. (1998). A social survey on the effects on environmental noise pollution in the city of Curitiba, Brazil. Applied Acoustics, 53, 245–253.

4. Babisch, W., Beule, B., Schust, M., Kersten, N., Ising, H., 2005. Traffic noise and risk of myocardial infarction. Epidemiology 16 (1), 33–40.

5. Buchta, E., & Vos, J. A. 1998. Field survey on the annoyance caused by sound from large firearms and road traffic. The Journal of the Acoustical Society of America, 104(5), 2890–2902.

6. Barner, J. 1983. Experimentelle landschaftsökologic. Stuttgart: Ferdinant Enke Verlag.

7. Barrigon Morillas, V. Gomez Escobar, J.A. Mendez Sierra, R. Vilchez Gomez and J. Trujillo Carmona, 2002. An environmental noise study in the city of Caceres, Spain, Appl. Acoust. 63, pp. 1061–1070

8. Booth, N. K. (1990). Basic elements of landscape architectural design (p315). İIlinois, USA: Waveland Press, Inc.

9. Burns SH. 1979. The absorption of sound by pine trees. J Acoust Soc Am, 65(3):658–61.

10. Canneli, G B (1974) Traffic noise pollution in Rome. Appl.Acoust. 7, 103–115.

11. Çepel, N. (1994). Landscape Ecology’ I.U. Forest Faculty, Published No. 429, 228, İstanbul.

12. Cowans, J.p., 1994. Handbook of Environmental Acoustic. Van No strand.




222

13. Cook, D. I., & Haverbeke, D. F. V. 1974. Trees and shrubs for noise abatement. University of Nebraska College of agriculture Experiments Bulletin, RB246.

14. Erlbeck, R. et al. (1974). Leitfaden zur karteierung der Schutz und Erholungsfunktionen des Waldes’, J.D. SauerlandersVerlag: Frankfurt am Wain, s. 80.

15. European Report, 1996. No. 2173, 9 November.

16. Embleton, T. F. W., 1963. Sound propagation in homogeneous and deciduous and evergreen woods. Journal of Acoustical Society of America 35, 1119–1125.

17. Eyring CF. Jungle acoustic. J Acoust Soc Am 1946; 18(2):257–76.

18. Elshorbagy, K A (1984) Environmental acoustic quality in Jeddah urban sites. Appl. Acoust. 17(4), 261–274.

19. Fang, C. F., Ling, D. L., 2003. Investigation of the noise reduction provided by tree belt. Landscape Urban Planning 63, 187–195.

20. Fang, C., Ling, D., 2005. Guidance for noise reduction provided by tree belts Landscape and Urban Planning 71, 29–34.

21. Finke, L. (1980). Kent planlaması Açısından Yeşil Alanların Kent iklimi ve Kent Havasını İyileştirme Yetenekleri(Çeviren: I, Aslanboğa). I.U. Orman Fak, Derg, 30(2), 225–255.

22. Garcia, A. (1997). Noise survey in the community of Valencia (Spain). Acustica, 839(3), 516– 521.

23. Grahn, P., Stigsdotter, U., Berggren Ba¨ rring, A.M., 2005. A planning tool for designing sustainable and healthy cities. The importance of experienced characteristics in urban green open spaces for people’s health and wellbeing. In: Quality and Significance of Green Urban Spaces. Conference proceedings, Van Hall Larenstein, Velp, 29–38.

24. H. Bogo, D.R. Gomez, S.L. Reich, R.M. Negri and E. San Roman, 2001. Traffic pollution in a downtown site of Buenos Aires City, Atmospheric Environment 35 pp. 1717–1727

25. Harris, R. A. (1986). Vegetative barriers: An alternative highway noise abatement measure. Noise Control Engineering

26. Journal, 27(l), 34–48, July–August. Haverbeke, D. F. (1971). Trees and shrubs for noise abatement. Research Bulletin Agricultural Experiment Station —University of Nebraska, No: 246.

27. Herrington, L.P., 1976. Effect of vegetation on the propagation of noise in the outofdoors. USDA Forest Service General Technical Report, US Rocky Mountain Forest Range Experimental Station, No. 25, pp. 229–233.

28. Huddart, L., 1990. The use of vegetation for traffic noise screening. Crowthorne, erkshire: U. K. Transport and Road Research Laboratory Research Report, p 238.




223

29. J. Kragh, 1981. Road traffic noise attenuation by belts of trees, Journal of Sound and Vibration 80 (74) 235–241.

30. Jamrah, H., Omari, A. A., & Sharabi, R. 2005. Evaluation of traffic noise pollution in Amman, Jordan. Environmental Monitoring and Assessment, 120, 499–525.

31. Jorge P. Arenas, 2 0 0 8. Potential problems with environmental sound barriers when used in mitigating surface transportation noise, science of the total environment 405, 173179.

32. K.A.L. Brown and C. Lam, 1987. Urban noise surveys, Appl. Acoust. 20 (1), pp. 23–39 33. Khilman, T., 2004. Noise pollution in cities, Curitiba and Go¨ teborg as examples. In:

proceedings of the Seminar—Environmental Aspects of Urbanization—Seminar in Honor of Dr. Mostafa Kamal Tolba, Gothenburg, Sweden, in CD.

34. Kura, S., Moritomo, M., & Maekava, Z. I., 1999. Transportation noise annoyance: A simulated environment study for road, railway and aircraft noises, Part 1: Overall annoyance. Journal of Sound and Vibration, 220(2), 251–278.

35. Lercher, P. 1995. Environmental noise and health: an integrated research perspective. Environmental International, 22, 117–129.

36. Li, B., Tao, S., & Dawson, R. W. (2002). Evaluation and analysis of traffic noise from the main urban roads in Beijing. Applied Acoustics, 63(10), 1137–1142, October.

37. Lorenz, E. (1975). Karayolları Ağaçlandırma Rehberi (Çeviren F. Tanrıverdi) Karayolları Genel Müdürlüğü Matbaası. Yayın, 214, 55, Ankara.

38. Macdonald B.C. 1977. "Proposal for noise control legislation", pub: Dep of Environment, Tehran, ,pp.A(5862).

39. Morillas, J. M. B., Escobar, V. G., Sierra, J. A. M., Gómez, R. V., & Carmona, J. T. (2002). An environmental noise Study in the city of Cáceres, Spain. Applied Acoustics, 63 (10), 1061– 1070, October.

40. Onuu,M. U. (2000). Road traffic noise in Nigeria. Measurements, analysis and evaluation of nuisance. Journal of Sound and Vibration, 233(4), 391–405.

41. Ozer, S., Akif Irmak, M., Yilmaz, H., 2007. Determination of roadside noise reduction effectiveness of Pinus sylvestris L. and Populus nigra L.in Erzurum, Turkey. Environmental monitoring and Assessment 1,1118.

42. Pathak, V.,Brahma, D., Tripathi, V., 2007. Dynamics of traffic noise in a tropical city Varanasi and its abatement through vegetation. Environmental monitoring and Assessment 1, 210.

43. Price Margaret, A., 1988. Sound attenuation through trees: Measurement and models. Journal of Acoustical Society of America 84, 1836–1844.




224

44. Rao, P. S., Gavane, A. G., Ankam, S. S., Ansari, M. F., Pandit, I. V., & Nema, P. (2004). Performance evaluation of a green belt in a petroleum refinery: A case study. Ecological Engineering, 23(2), 77–84.

45. Reethof, G. 1973. Effect of planting on radiation of highway noise. Journal of the Air Pollution Control Association, 23 (3), 185–189.

46. Skarback, E., 2007. Urban forests as compensation measures for infrastructure development. Urban Forestry & Urban Greening. 6, 279–285.

47. Stansfeld, S. A., & Matheson, M. P. 2003. Noise pollution: Nonauditory effects on health. British Medical Bulletin, 68, 243–257.

48. Sutton, P., 2003.Process plant noise: Evaluation and control, Applied Acoustics volume9, issue1, 1733.

49. Tyagi, V., Kumar, K., Kumar, V., 2006.A study of the spectral characteristics of traffic noise attenuation by vegetation belts in Delhi, Applied Acoustics 67,926–935.

50. Williams, I. D., & Mc Creae, I. S. 1995. Road traffic nuisance in residential and commercial areas. Science of Total Environment, 169, 75–82.

51. Yang,J. & Gan,W.S.2001. On The Actively Controlled Noise Barrier. Journal of Sound and Vibration.240 (3):592597.

52. Zannin, P. H., Zanin, F. B., & Barbosa, W. A. (2002). Environmental noise pollution in the city of Curitiba, Brazil. Applied Acoustic, 63, 351–358.

Documents

The Effect of Pure and Mixed Plantations of Robinia ... · PDF fileThe Effect of Pure and Mixed Plantations of Robinia Pseudoacasia and Pinus ... Chitgar forest park of ... making