The Content of Sulphur in the Soil and Plant from Park Areas Exposed to Traffic Pollution

Sulphur occurs in many environmental compounds. Source of this element may be natural as also anthropogenic origin, for example related with the development of road traffic. The aim of this study was to evaluate the impact of traffic on the content of total and sulphate sulphur in forest soils and plant material. The selected physicochemical properties of soils were determined: soil texture by laser diffraction method, soil pH by potentiometric method, total organic carbon (TOC) by Tiurin method. The content of total and sulphate sulphur in research material was determined by Bardsley-Lancaster method modified by COMN-IUNG. All analyses were performed in three replicates and the verification of the results was based on the certified material Till-3. Statistical analysis of the results were performed in Statistica 12.0 for Windows Pl software. Examined research material was characterized by medium, high and anthropogenic origin content of total and sulphate sulphur. Undertaken studies showed that the traffic could have an adverse influence on the content of sulphur in soils and plant material.

Landscape parks are unique places in terms of species richness, diversity of landscape and variety of geomorphic forms (Helmuth & Dudek, 2002).Through insight into many advantages, these areas are under legal protection (Regulation No. 92,item. 880).Myślęcinek Forest Park for Culture and Leisure, constituting an area of research, is the biggest city park in Poland.These site is located near to urban areas and the surface takes 830 ha (Dynarz & Wiśniewski, 1997).
Sulphur occurs in many environmental components e.g.air, water, soil.It is an element widely occurring in ecosystems.Sources of sulphur in environment may be natural as also anthropogenic origin.The biggest threat with regard to the amount of sulphur emissions to the environment comes from human activities i.e. exploitation of natural resources, the development of road traffic, storage of waste and many others (Sherer, 2001).Road traffic is the source of substances in environmental components (Pallvani & Harrison, 2013).The content of selected compounds are directly proportional to vehicle speed.Higher velocity causes the increased emissions (Duong & Byeong-Kyu, 2011).Pollution from traffic contributes to gradual degradation process of soil and vegetation cover in the areas located about 500 m from road (Sławiński, Gołąbek, & Senderak, 2014).Dust fall and gas concentrations have major impact on the calculated percentage of deterioration environmental quality of the forest taking into account the distance of forest surface from the emission source.This is because it undoubtedly determines the amount of precipitation and the concentration of gases in base: the farther the distance, the smaller fall of the dust and gas concentrations (K.Sporek & M. Sporek, 2007).Furthermore, fuel combustion processes are the main source of sulphur in environment (Bąbelewska, 2013).Sulphur compounds may be affected directly on change the soil pH (Jaggi & Freedman, 1992).Lower soil pH can cause launching other compounds for example heavy metals like aluminium, nickel, mercury (Karczewska & Kabała, 2010).Therefore, pollutant emissions such as sulphur must be monitored to provide proper quality of environmental components and prevent of their degradation (Franco et al., 2013)   ) 2) ) 2) ) 2) ) 2) ) 2) ) 2) ) 2) ) 2) ) 2) Journal of A

Analysis of the Sulphur Content
Total content of analysed elements have taken the following values in soil samples: total sulphur from 22.4 mg•100 g -1 to 53.1 mg•100 g -1 in surface samples and from 19.3 to 27.2 in subsurface samples, sulphate sulphur from 1.3 to 3.8 mg•100 g -1 in surface samples and from 1.5 to 3.7 mg•100 g -1 in subsurface samples (Table 2).
Total content of analysed elements have taken the following values in pine bark samples: total sulphur from 39.2 mg•100 g -1 to 84.4 mg•100 g -1 and sulphate sulphur from 10.5 to 157.8 mg•100 g -1 (Table 3).
Total content of analysed elements have taken the following values in pine needles samples: 1-years increments of needles total sulphur from 78.3 mg•100 g -1 to 341.9 mg•100 g -1 and sulphate sulphur from 1.2 to 4.9 mg•100 g -1 , 2-years increments of needles total sulphur from 87.1 to 415.0 mg•100 g -1 and sulphate sulphur from 1.5 to 5.3 mg•100 g -1 , 3-years increments of needles total sulphur from 159.2 to 461.5 mg•100 g -1 and sulphate sulphur from 0.8 to 5.7 mg•100 g -1 (Table 4).

Morphological Analysis of Pine Needles
Morphological analysis of three-years increments of needles of Pinus sylvestris L. allows to determine length, width and surface at each increment.
The 1-year increments of pine needles have taken the following values: length from 4.38 to 5.93 cm, width from 0.06 to 0.09 cm and surface from 0.25 to 0.52 cm.The 2-year increments of pine needles have taken the following values: length from 5.45 to 7.21 cm, width from 0.07 to 0.09 cm and surface from 0.40 to 0.63 cm.The 3-year increments of pine needles have taken the following values: length from 6.75 to 7.95 cm, width from 0.08 to 0.12 cm and surface from 0.56 to 0.97 cm (Table 4).

Statistical Analysis
Calculated correlation coefficients confirmed the significant relations: in soil samples between the content of total sulphur and the content of sulphate sulphur (r = -0.532at p < 0.05) (Figure 2); in pine bark between the content of total sulphur and two properties of soil samples: [H+] in pH H2O (r = -0.441at p < 0.05) (Figure 3a) and the content of clay (r = 0.534 at p < 0.05) (Figure 3b); in pine needles between the content of total sulphur and the surface of needles (r = 0.434 at p < 0.05) (Figure 4).

Discussion
The content of total sulphur in examined soil sample ranged from 19.3 to 53.1 mg•100 g -1 and sulphate sulphur ranged from 1.3 to 3.7 mg•100 g -1 .Examined soils were characterized by medium and high content of total sulphur and also by medium, high and anthropogenic origin content of sulphate sulphur.According to the guidelines developed by Kabata-Pendias (2010) examined soil may be qualify as a soil with medium and high content of total sulphur and as a soil with medium, high and anthropogenic origin content of sulphate sulphur.Therefore, that sulphate sulphur is one of the forms in soil especially contributing to acidification of soils, monitoring the level of this compound is such an important factor.The content of total sulphur in examined pine barks ranged from 39.2 to 84.4 mg•100 g -1 and sulphate sulphur ranged from 10.5 to 157.8 mg•100 g -1 .Examined pine needles were characterized by a content of total sulphur in ranged from 78.3 to 461.5 and sulphate sulphur from 0.8 to 5.7 mg•100 g -1 .Referring the results obtained from the conducted research to the current state of knowledge can be stated that the total content of sulphur in plant materials was on a medium level and sulphate sulphur on low.This indicates a slight anthropogenic impact on the local flora.Despite this, due to the proximity of routes with high traffic occurs need for constant monitoring of the studied area.
Similar research were conducted by Licznar and Licznar (2005) in city park in Wroclaw (Poland).The mean content of total sulphur in soil from Szczytnicki Park (Wroclaw) was 116.0 mg•100 g -1 .Research conducted by Kalambasa and Godlewska (2010) showed that mean content of total sulphur in loamy sands was 6.5 mg•100 g -1 .
In soil fertilised with macroelements mean content of sulphate sulphur ranged from 82.2 to 125.0 mg•100 g -1 (Siwik-Ziomek, Lemanowicz, & Koper, 2016).Another research reported that mean content of sulphate sulphur in forest soil ranged from 5.5 to 10.5 mg•100 g -1 (Koper, Piotrowska, & Siwik-Ziomek, 2008).Research conducted by Szopka et al. (2011) showed that soils from Karkonosze National Park were characterized by high volatility and the content of sulphate sulphur ranged from 200.0 to 36,000.0 mg•100 g -1 .Kulczycki and Spiak (2004) in the arable layer (0-20 cm) of eighty soils from south-west Poland, reported that the participation of the sulphate sulphur was about 700,000.0 mg•100 g -1 .Other studies indicated that the content of sulphate sulphur in soils of road Siedlce city ranged from 150,000.0 to 1,700,000.0mg•100 g -1 (Kalembasa & Godlewska, 2005).Boratyński et al. (1975) reported that in methodological research of soil samples content of S-SO 4 -2 ranged from 0.3 to 0.5 mg•100 g -1 .According to research conducted by Terelak and Motowicka-Terelak (2000) the content of sulphate sulphur in Polish soils ranged from 0.01 to 50.0 mg•100 g -1 .More than 55% of soils are areas with low content of S-SO 4 -2 .Surface of areas with medium and high content of sulphate sulphur constitutes appropriately: 25.1 and 13.1%, and anthropogenically contaminated by sulphur only 3.7% (Terelak, 2005).
Close to the Kola smelters content of total sulphur in pine bark was a twice as high as the other side of border of the Finland (Poikolainen, 1997).Research conducted by Manninen et al. (1997) showed that the content of sulphate sulphur in pine needles takes values from 0.6 to 1.2 mg•100 g -1 .In pine needles from northernmost Europe the content of sulphate sulphur ranged from 7,410.0 to 20,170.0 mg•100 g -1 (Raitio, Tuovinen, & Anttila, 1995).Received results were very high and probably it was connected with SO 2 emissions into the atmosphere in the surrounding areas.In areas highly industrialized the content of total sulphur in pine needles ranged from 6,000.0 to 10,000.0 mg•100 g -1 , while in areas where there is no pollution of air content of total sulphur ranged from 300.0 to 1,200.0 mg•100 g -1 (Grodzińska, 1977).Research conducted by Staszewski et al. (2008) reported that the content of sulphate sulphur in 1-year increments of pine needles from Pieniny National Park was 700.0 mg•100 g -1 .Other studies on the pine needles from this area showed that the content of total sulphur ranged from 500.0 to 999.0 mg•100 g -1 (Panek & Szczepańska, 2005).Assessment of sulphur content in soils is necessary in terms of impact of this element for mobility of heavy metals and deterioration of chemical properties of soil especially launch of aluminium and losses of magnesium (Motowicka-Terlak & Dudka, 1991).The content of sulphur in Polish soils takes average values from 500 to 5000 mg•100 g -1 (Gorlach & Mazur, 2001).
To sum up, undertaken studies shows that the traffic have slight influence on the content of total and sulphate sulphur in soils and plant material.So far, conducted only few similar studies, relating to the assessment of environmental pollution by sulphur compounds as a result of traffic road.Many other studies were primarily aimed to assess the various industries on the content these elements in environmental components.Therefore undertaken research complementing the state of knowledge.

Figure 2 .Figure 3 .
Figure 2. Correlation between the content of total sulphur and sulphate sulphur in soil samples

Table 2 .
Physicochemical properties and the content of total and sulphate sulphur in soil samples (mean for three years of investigation) Soil sample and depth (cm) pH H2O pH KCl TOC (g•kg -1 ) Clay (%) S total (mg•100 g -1 ) S-SO 4 2-(mg•100 g -1 )

Table 3 .
The content of total and sulphate sulphur in pine bark

Table 4 .
Morphological analysis and the content of total and sulphate sulphur in pine needles