Journal of Ecological Engineering Received: 2019.08.29 Revised: 2019.09.26 Volume 20, Issue 10, November 2019, pages 110–117 Accepted: 2019.10.10 Available online: 2019.10.30 https://doi.org/10.12911/22998993/113075

Multidimensional Assessment of Variation of Physio-Chemical Parameters of the Liwiec River Basin Waters

Katarzyna Rymuza1

1 Faculty of Natural Sciences, University of Natural Sciences and Humanities, ul. Prusa 14, 08-110 Siedlce, e-mail: [email protected]

ABSTRACT The objective of the work was to utilise multidimensional statistical methods to assess the physio-chemical status of waters of the River Liwiec catchment. The water quality assessment and comparison in terms of fifteen param- eters were based on the monitoring data collected at eight measurement points in 2017. The principal component analysis demonstrated that the water quality in the River Liwiec catchment was principally conditioned by water temperature, pH, soluble oxygen content, nitrite nitrogen content and organic carbon content. The cluster analysis conducted based on principal components yielded three clusters of measurement points. The first cluster included the following measurement points: Liwiec-Kamieńczyk, Liwiec Wólka Proszewska, Liwiec Borzychy and Liwiec Krześlin. The waters at these points contained the least organic carbon and ammonium nitrogen. The second clus- ter consisted of the Muchawka Żytnia and Muchawka Rakowiec tributaries characterised by the highest amount of phosphorus, Kiejdhal nitrogen, ammonium nitrogen, nitrite nitrogen and organic carbon. The third cluster was made up of the Kostrzyń Proszew and Kostrzyń Łączka tributaries, both having the lowest values of nearly all the examined parameters.

Keywords: pollution of surface waters, cluster analysis, quality ranking, the River Liwiec

INTRODUCTION AND WORK OBJECTIVE Ostrowskia 2007, Grabińska 2011, Kanownik et al. 2013]. The natural factors include geological The River Liwiec is a left-bank tributary of makeup, soil type, climatic and hydrological con- the River Bug. With a length of about 126 km, its ditions as well as the processes occurring in the source is found in the vicinity of Sobicze, Zbuc- soil environment. In turn, the Anthropogenic fac- zyn Commune (), Siedlce County (Powi- tors encompass the type of terrain use and man- at). The river runs through the Siedlecka Upland, agement [Bogdał et al. 2012, Kowalik et al. 2014, Węgrów Basin and Wołomińska Lowland and ter- 2015]. In the basins, the total area of which in- minates in the vicinity of Kamieńczyk, the Lower cludes a marked share of ploughed land, the qual- Bug Valley [Starczewski et al. 2014]. There are ity of surface waters is predominantly affected no embankments along the river channel and the by crop- and fertiliser-related pollutants [Kiryluk Liwiec is barely regulated, apart from the upper and Rauba 2009, Kornaś and Grześkowiak 2011, reach and several parts of the lower reach [Kot Szymczyk and Rafałowska 2011]. The waters 1995]. As the river runs close to a large urban ag- leaving the basins located in agricultural areas glomeration, it has become a very attractive place tend to contain the highest concentration of ni- of weekend recreation. Thus, the quality of its trogen and phosphorus compounds [Ławniczak water has become of particular importance, be- et al. 2008]. An accumulation of pollutants in the cause it conditions the river’s social, economic water environment may be also boosted by the and recreational use. wastewater from industrial facilities and urban The quality of surface waters is modified by agglomerations [Mosiej et al. 2007, Lampart- natural and anthropogenic factors [Bogdał and Kałużniacka et al. 2012, Policht-Latawiec et al.

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2013, 2015]. The pollution poses a threat to the − conductivity at 20°C (uS/cm), X6 – dissolved proper functioning of water ecosystems [Jaskuła substances (mg/l), X7 – overall hardness (mg et al. 2015, Pytka et al. 2013]. CaCO3/l), X8 − water pH, X9 – ammonium nitro-

The water quality assessment is performed gen (mg N-NH4/l), X10 –Kjeldahl nitrogen (mg by Voivodeship Inspectorates for Environmental N/l), X11 – nitrate nitrogen (mg N-NO3/l), X12 –

Protection (WIOŚ). The monitoring results con- nitrite nitrogen (mg N-NO2/l), X13 – total nitrogen sist of a large amount of data which is difficult to (mg N/l), X14 – phosphate phosphorus content (mg analyse and interpret unequivocally. As a result, PO4/l), X15 – total phosphorus content (mg P/l). such analyses employ multidimensional statisti- The initial data analysis consisted in calculat- cal methods such as principal component analy- ing the basic statistical measures: mean, variation sis, cluster analysis, factorial analysis or multidi- coefficient, and maximum and minimum values. mensional comparative analysis [Akin et al. 2011, The principal component analysis was used Boyacioglu et al. 2010, Brahman et al. 2013]. in order to analyse the multidimensional variation The objective of the work was to (i) use mul- of physio-chemical parameters at measurement tidimensional statistical methods for assessing the points. As the examined indicators had different physio-chemical condition of waters of individu- units, the variables were standardised. Selection al stretches of the River Liwiec and its tributaries, of the number of components included in further and (ii) rank the quality of these waters based on analysis was based on the Kaisler criterion ac- the following multidimensional statistical meth- cording to which analysis of the components with ods of data analysis: principal component, cluster eigenvalue greater than 1 is performed. Next, analysis and multidimensional comparative anal- the cluster analysis was applied to group the ysis using the zero unitarisation method. measurement points located in the River Liwiec basin according to water quality. The grouping was based on the Ward’s method, and employed MATERIALS AND METHODS the Euclidean distance. The Mojena rule was used to determine the dendrogram cut-off point The analysis of monitoring data collected [Mojena 1977]. in the year 2017 was performed, including the The measurement points were ranked ac- following eight measurement points: Liwiec- cording to the physio-chemical quality of waters Kamieńczyk, Liwiec-Krześlin, Liwiec-Wólka taking into account all the parameters and based Proszewska, Liwiec Borzychy, Muchawka-Ra- on multidimensional comparative analysis which kowiec, Muchawka-Żytnia, Kostrzyń-Łączka and relies on obtaining, through normalisation, unit- Kostrzyń- Proszew. less values of characteristics. As a result, a single The following chemical parameters were (instead of many) synthetic variable is formed, analysed: X1 – water temperature (°C), X2 − dis- which represents a complex phenomenon. solved oxygen (mg O2/l), X3 – BOD5 (mg O2/l), Normalisation of variables was based on the

X4 – total organic carbon content (mg C/l), X5 method of zero unitarisation. The character of the

Fig. 1 The River Liwiec basin

111 Journal of Ecological Engineering Vol. 20(10), 2019 variables was determined prior to normalisation. The following stimulants were assumed: wa- s (3) ter temperature, water pH and dissolved oxygen 1 content. The remaining variables were classified qi = ∑ zij, as destimulants. The normalisation of stimulants where s denotes thes numberi=1 of variables enter- was preformed according to the following formu- ing analysis. la [Kukuła 2000]: The values of the synthetic measure qq were put in order to rank river stretches and its tributar-

(1) ies according to water quality. 1 ij ij i All the calculations were performed in STA- In turn, normalisationz = i ofi (destimulantsx − a ) was carried b − a TISTICA 12.0 and EXCEL. out using the following formula:

(2) ANALYSIS OF RESULTS ij 1 i ij z = i i (b − x ) where: zij − normalisedb − a value of the i-th charac- Means, minimum and maximum values of teristic and j-th river section, i = 1, ...,19, water quality parameters for the River Liwiec Ba- j =1, ...,12, sin are shown in Table 1. The lowest variation was xij − value of the i-th characteristic and found for pH (3.792%) and water temperature j-th river section, i = 1, ...,19, j =1, ...,12, (V = 7.85%), it being the highest for ammonium a i − minimum value of the i-th nitrogen (90.25%) and nitrate nitrogen (36.36%). characteristic, Principal component analysis demonstrated b i − maximum value of the j-th that the water quality in the River Liwiec ba- characteristic. sin was affected by the characteristic associated The obtained values of normalised variables with the first three principal components: PC1, were used to calculate, for each measurement PC2 and PC3 (as indicated by their eigenvalues point, the synthetic measure (aggregate evalua- which exceed 1). The components accounted for tion) following the formula: about 90% of the total (combined) variance of the

Table1. Basic statistics of physio-chemical parameters of the River Liwiec Basin min max Parameter mean V value River value River Muchawka Water temperature 16.744 7.853 14.950 19.233 Liwiec Kamieńczyk Rakowiec Dissolved oxygen 7.848 14.709 6.583 Muchawka Żytnia 9.833 Liwiec Kamieńczyk BOD5 3.123 10.824 2.683 Muchawka Żytnia 3.767 Liwiec Kamieńczyk Muchawka Total organic carbon 13.159 10.317 10.958 Liwiec Kamieńczyk 15.700 Rakowiec Conductivity at 20°C 461.563 12.459 360.333 Kostrzyń Łączka 566.500 Liwiec Wólka Liwiec Wólka Dissolved substances 306.458 12.602 234.333 Kostrzyń Łączka 376.333 Proszewska Overall hardness 239.958 12.463 190.333 Kostrzyń Łączka 291.333 Liwiec Krześlin pH 7.440 3.792 6.983 Kostrzyń-Łączka 7.967 Liwiec Kamieńczyk Muchawka Ammonium nitrogen 0.137 90.250 0.029 Liwiec Kamieńczyk 0.443 Rakowiec Muchawka Kjeldahl nitrogen 1.969 15.181 1.610 Kostrzyń Proszew 2.582 Rakowiec Liwiec Wólka Nitrate nitrogen 1.636 41.258 0.620 Kostrzyń-Łączka 2.603 Proszewska Muchawka Nitrite nitrogen 0.026 36.360 0.013 Liwiec Kamieńczyk 0.041 Rakowiec Total nitrogen 3.645 21.122 2.427 Kostrzyń Łączka 4.454 Liwiec Kamieńczyk Phosphate phosphorus (V) 0.069 16.990 0.052 Liwiec Krześlin 0.086 Muchawka Żytnia Muchawka Total phosphorus 0.164 17.012 0.129 Kostrzyń Proszew 0.226 Rakowiec

112 Journal of Ecological Engineering Vol. 20(10), 2019 multidimensional variation in the water quality development of algae and reduce the dissolved parameters (Table 2). oxygen levels. The concentration of the nitrogen The first principal component was strongly and phosphorus compounds in river water is low positively associated with the water temperature in the basins with predominantly sandy soils, and (0.961), water pH (0.954), dissolved oxygen con- a rich forest cover as well as high in the basins tent (0.899) and nitrite nitrogen content (0.807), where soils are predominantly compacted and and negatively correlated with organic carbon used for intensive agricultural production pur- content (-0.835). The parameters had the greatest poses [Melcer and Olejnik 2006]. Some authors share in the multivariate variation in water qual- stress the fact that a rich forest cover contributes ity. The values of correlation coefficients indicate to the reduced infiltration of pollutants from sur- that the in river stretches where water contained face sources to the water. In such basins, a decline relatively high amounts of organic carbon, lesser in the concentration of these compounds in the dissolved oxygen, lower temperature and lower river waters along the river course is observed pH values were observed. The total and phosphate because of the process called self-purification of phosphorus contents, nitrite and Kjeldahl nitro- waters [Górecki and Olejnik 2005]. gen contents as well as dissolved substances were The location of characteristics in the system the most strongly associated with the second prin- of the first two principal components indicates cipal component, which accounted for about 33% that there was a strong positive association of variation. An increase in the amount of both forms the organic carbon content with the ammonium of phosphorus was followed by a rise in the nitrite nitrogen content, as well as the total nitrogen con- and Kjeldahl nitrogen content and dissolved sub- tent and dissolved substances with conductivity. stances. The third component, predominantly as- Moreover, at the measurement points where the sociated with BOD5 (0.910), accounted for over organic nitrogen content was higher, a lower dis- 12% of multivariate water quality in the Liwiec solved oxygen content was found (Fig. 1). River basin (Table 1). Nachlik [2004] claims that The cluster analysis yielded three clusters depending on their concentration, the nitrogen of measurement points in the River Liwiec compounds in surface waters may stimulate the basin which had different physio-chemical

Table 2. Eigenvalues and correlation coefficients between water quality parameters and three principal components

Parameter PC1 PC2 PC3 Water temperature 0.961 0.096 0.089 Dissolved oxygen 0.899 0.170 0.351 BOD5 0.337 -0.147 0.910 Total organic carbon -0.835 -0.447 -0.056 Conductivity at 20°C 0.648 -0.652 -0.391 Dissolved substances 0.603 -0.722 -0.271 Overall hardness 0.663 -0.640 -0.386 pH 0.954 -0.007 0.152 Ammonium nitrogen -0.683 -0.576 0.360 Kjeldahl nitrogen -0.266 -0.711 0.485 Nitrate nitrogen 0.807 -0.519 -0.003 Nitrite nitrogen -0.442 -0.788 -0.209 Total nitrogen 0.618 -0.747 0.167 Phosphate phosphorus (V) -0.440 -0.839 -0.155 Total phosphorus -0.353 -0.850 0.323 Eigenvalue 7.86 5.60 1.97 Cumulated variance 46.26 79.25 90.82

1 – water temperature (°C), 2 − dissolved oxygen (mg O2/l), 3 – BOD5 (mg O2/l), 4 – total organic carbon (mg C/l),

5 – conductivity at 20°C (uS/cm), 6 – dissolved substances (mg/l), 7 – overall hardness (mg CaCO3/l), 8 − water pH,

9 – ammonium nitrogen (mg N-NH4/l), 10 – Kjeldahl nitrogen (mg N/l), 11 – nitrate nitrogen (mg N-NO3/l),

12 – nitrite nitrogen (mg N-NO2/l), 13 – total nitrogen (mg N/l), 14 – phosphate phosphorus (mg PO4/l), 15 – total phosphorus (mg P/l).

113 Journal of Ecological Engineering Vol. 20(10), 2019 parameters of water (Fig. 3). The first cluster and total phosphorus. The worst parameters included four measurement points: Liwiec- were found for the waters of the Muchawka- Kamieńczyk, Liwiec Wólka Proszewska, Li- Żytnia and Muchawka-Rakowiec rivers, as wiec Borzychy and Liwiec Krześlin. The sec- they had the highest amounts of e.g.: organic ond cluster consisted of the Muchawka Żytnia carbon, phosphorus and all the nitrogen forms. and Muchawka Rakowiec tributaries, and the The research by Grabińska [2011] as well as third one was made up of Kostrzyń Proszew Szymczyk and Rafałowska [2011] demonstrat- and Kostrzyń Łączka (Fig. 2). ed that the main sources of surface water pollu- The waters of the measurement points form- tion with nitrogen and phosphorus compounds ing group 1 had the highest mean values of most include the run-off of the pollutants from cul- physio-chemical parameters, that is: water tem- tivated land and wastewater. High fertilisation perature, dissolved oxygen content, BOD5, con- levels may also contribute to the leaching and ductivity, dissolved substances, overall hardness transfer of these compounds into surface waters and nitrate nitrogen content. Group 1 had the low- [Kiryluk and Rauba 2011]. est values of organic carbon content and ammoni- um nitrogen content. The waters in group 3 (tribu- tary of the River Kostrzyń) had the lowest values CONCLUSIONS of almost all the parameters excluding dissolved oxygen content, ammonium and nitrite nitrogen 1. Principal component analysis demonstrated contents, and phosphate phosphorus content. The that the waters of the River Liwiec at the ana- tributary of the River Liwiec − Muchawka − con- lysed points were the most affected by char- tained the highest amount of phosphorus, Kjel- acteristics associated with the first principal dahl nitrogen, ammonium and nitrite nitrogen, component PC1 (water temperature, water pH, and organic carbon (Table 2). dissolved oxygen content, nitrite nitrogen con- Table 4 presents the measurement points tent and organic carbon content). ranked according to water quality. The values of the synthetic variable indicate that water at 2. The values of correlation coefficients indicate the Kostrzyń Proszew and Kostrzyń Łączka that in the river stretches where water con- measurement points was of the best quality, as tained relatively high amounts of organic car- it had the lowest values of dissolved substanc- bon, lesser dissolved oxygen, lower tempera- es, overall hardness, most of the nitrogen forms ture and lower pH values were observed.

Fig. 2. Location of physio-chemical parameters of the River Liwiec waters in the space of the first and second principal component

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Table 3. Mean values of characteristics obtained by means of cluster analysis Parameter Group 1 Group 2 Group 3 Water temperature 17.65 15.84 15.83 Dissolved oxygen 8.83 6.67 7.06 BOD5 3.21 3.10 2.97 Total organic carbon 12.19 14.76 13.50 Conductivity at 20°C 499.42 465.50 381.92 Dissolved substances 330.46 313.42 251.50 Overall hardness 262.21 234.92 200.50 pH 7.65 7.25 7.21 Ammonium nitrogen 0.06 0.29 0.13 Kjeldahl nitrogen 1.89 2.40 1.70 Nitrate nitrogen 2.21 1.36 0.77 Nitrite nitrogen 0.02 0.04 0.02 Total nitrogen 4.15 3.80 2.49 Phosphate phosphorus (V) 0.06 0.08 0.06 Total phosphorus 0.16 0.20 0.14

Table 4. River Liwiec basin waters ranked based on multidimensional comparative analysis Measurement point Value of synthetic variable Rank Kostrzyń-Proszew 10.90 1 Kostrzyń-Łączka 9.92 2 Liwiec-Kamieńczyk 9.67 2 Liwiec-Krześlin 8.48 4 Liwiec-Borzychy 8.41 5 Liwiec-Wólka Proszewska 6.54 6 Muchawka Żytnia 6.09 7 Muchawka-Rakowiec 2.69 8

Fig. 3. Dendrogram of the division of the River Liwiec basin

3. On the basis of the cluster analysis, the mea- included four measurement points: Liwiec- surement points in the River Liwiec were di- Kamieńczyk, Liwiec Wólka Proszewska, Li- vided into 3 groups basin which had different wiec Borzychy and Liwiec Krześlin. The sec- physio-chemical parameters. The first cluster ond cluster consisted of the Muchawka Żytnia

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and Muchawka Rakowiec tributaries, while the 7. Grabińska B. 2011. Changes in the quality of the third one was made up of Kostrzyń Proszew river water on the background of the diversity of and Kostrzyń Łączka natural conditions and usage basin. The resources conservation and water quality in rural landscape. 4. The waters of the measurement points form- Współczesne Problemy Kształtowania i Ochrony ing group 1 had the highest mean values of Środowiska. Olsztyn. UWM, 223–253. most physio-chemical parameters. The waters 8. Jaskuła J., Sojka M., Wicher-Dysarz, J., 2015. Anal- in group 3 (tributary of the River Kostrzyń) iza tendencji zmian stanu fizykochemicznego wód had the lowest values of almost all the param- rzeki głównej. Inżynieria Ekologiczna, 44, 154–161. eters excluding the dissolved oxygen content, 9. Kanownik W., Kowalik T., Bogdał A., Ostrowski ammonium and nitrite nitrogen contents, and K., 2013. Quality categories of stream water includ- phosphate phosphorus content. ed in a Small Retention Program. Pol. J. Environ. Stud., 22(1), 159–165. 5. The values of the synthetic variable indi- 10. Kiryluk A., Rauba M. 2011. Impact of agriculture on cate that the water at the measurement point the concentration of total phosphorus in the surface Kostrzyń Proszew and Kostrzyń Łączka was water catchment area Ślina. Inżynieria Ekologiczna, of the best quality, as it had the lowest values 26, 122–132. of dissolved substances. The worst parameters 11. Kornaś M., Grześkowiak A., 2011. Wpływ were found for the waters of the Muchawka- użytkowania zlewni na kształtowanie jakości Żytnia and Muchawka-Rakowiec rivers, as wody w zbiornikach wodnych zlewni rzeki Drawa they had the highest amounts of e.g.: organic [The impact of land use on water quality in water- carbon, phosphorus and all the nitrogen forms. reservoirs of the Drawa River catchment]. Woda- Środowisko-Obszary Wiejskie, 11, 1(33), 125–137. 12. Kot H. (red.), 1995. Przyroda województwa REFERENCES siedleckiego, Zakład Badań Ekologicznych ‚Ekos’, Siedlce, 141−155. 1. Akin B.S., Atici T., Katircioglu H. Keskin F., 13. Kukuła K., 2000. Metoda unitaryzacji zerowanej, 2011. Investigation of water quality on Gökçekaya PWN Warszawa. dam lake using multivariate statistical analysis, in 14. Lampart-Kałużniacka M., Wojcieszonek A., Pikuła Eskişehir. Environmental Earth Sciences, 63(6), K., 2012. Ocena stanu ekologicznego wód rzeki 1251–1261. Regi na odcinku w obszarze miasta Gryfice. An- 2. Bogdał A., Kowalik T., Kanownik W., Ostrowski nual Set The Environment Protection, 14, 437–446. K., Wiśnios M., 2012. Ocena stanu fizykochemicz­ 15. Ławniczak A. E., Zbierska J., Kupiec J., 2008. nego wód opadowych i odpływających ze zlewni Changes of nutrient concentrations in water sensi- potoku Wolninka. Gaz, Woda i Technika Sanitarna, tive to nitrate pollution from agricultural sources in 8, 362–365. the Samica Stęszewska river catchment. Annals of 3. Bogdał A., Ostrowski K., 2007. Wpływ rolniczego University of Life Sciences Land Reclama- użytkowania zlewni podgórskiej i opadów atmos- tion, 40, 15–25. ferycznych na jakość wód odpływających z jej ob- 16. Mecler B., Olejnik M., 2006. Wpływ wybranych szaru. Woda-Środowisko-Obszary Wiejskie, 7(20), czynników na zanieczyszczenie związkami biogen- 59–69. nymi powierzchniowych wód płynąch w zlewni 4. Boyacioglu H., Boyacioglu H., 2010. Detection of Baryczy. Acta Sci. Pol., Form. Circum., 5(2), 59–71. seasonal variations in surface water quality using 17. Mojena, R., 1977. Hierarchical grouping methods discriminant analysis. Environmental monitoring and stopping rule: an evaluation. The Computer and assessment, 162(1–4), 15–20. Journal., 20, 359−363. 5. Brahman, K. D., Kazi, T. G., Afridi, H. I., Naseem, 18. Mosiej J., Komorowski H., Karczmarczyk A., Suska S., Arain, S. S., Wadhwa, S. K., Shah, F., 2013. Si- A., 2007. Wpływ zanieczyszczeń odprowadzanych multaneously evaluate the toxic levels of fluoride z aglomeracji łódzkiej na jakość wody w rzekach and arsenic species in underground water of Thar- Ner i Warta. Acta Sci. Pol., Formatio Circumiectus, parkar and possible contaminant sources. A mul- tivariate study. Ecotoxicology and Environmental 6(2), 19–30. Safety, 89, 95–107. 19. Nachlik E., 2004. Identyfikacja i ocena antropogenic- 6. Górecki K., Olejnik M., 2005. Changes in levels znych oddziaływań na wody i ich skutków wraz ze ws- of nitrogen compounds in water of Warta river on kazaniem części wód zagrożonych nieosiągnięciem Oborniki-Skwierzyna stretch. Acta Sci. Pol., Form. celów środowiskowych określonych prawem. Meto- Circ. 4(2), 21–30. dyka realizacji. PK, Kraków.

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