1Sediments accumulating in the bottom of valleys of various orders document the processes taking place in drainage basins (Bork, 1989; Lang and Höhnscheid, 1999; Schmitt et al., 2006; Dotterweich, 2008). The sediment accumulation rate indirectly reflects the intensity of geomorphological processes. The key task is to determine the age of the particular layers. The radiocarbon method can be used for the direct dating of sediments older than 200-350 years (Stuiver and Polach, 1977). The age of younger sediments is frequently determined indirectly, based on the vertical variation in the concentration of the selected chemical elements in profiles. The “indirect dating” method relies on the correlation of content changes with specific, known facts related to various stages of human impact on the environment (Matschullat et al., 1997; Lecce and Pavlovsky, 2001; Klimek, 2002; Ciszewski and Malik, 2004). In order to be used in the datings, chemical elements or their isotopes must meet specific requirements, the most important of which are: (i) fast and durable binding in the sediment (low mobility); (ii) anthropogenic input exceeding the natural levels several times; (iii) a good understanding of the conditions of behaviour in the environment; (iv) relatively easy detectability (Ritchie and McHenry, 1990; Stach, 1991). Most frequently, heavy metals and artificial radioisotopes (137Cs) or, much more seldom, phosphorus, serve as such anthropogenic stratigraphic markers. They all meet the criteria mentioned above.
2The sedimentation rate is most often estimated using the artificial radioisotope 137Cs, which was first released into the environment in the mid-1950s; the maximum of its global input occurred in the early 1960s. The methodology of studying erosion and sedimentation processes with the use of this isotope is discussed in several works (e.g., Ritchie and McHenry, 1990; Walling and He, 1997; Zapata, 2003).
3The history of heavy metal inputs, recorded in fluvial and lacustrine sediments, is commonly used in the dating of correlative sediments (e.g., Hudson-Edwards and Macklin, 1999; Ciszewski, 2003; Audry et al., 2004; Graney and Eriksen, 2004). Knowing the time of the input of specific elements, isotopes (markers) into the environment, combined with data concerning their vertical variation in sediment profiles, enables the dating of specific layers. Due to lower heavy metal content in colluvia, chemostratigraphy is used more rarely in the study of slope processes, and only a few studies have been published so far (Zgłobicki and Rodzik, 2007; Zádorová et al., 2013). For instance, G. Clemens and K. Stahr (1994) estimated the rates of erosion and accumulation for several drainage basins in SW Germany based on a distinctive increase in phosphorus, lead, and cadmium concentration in the upper part of colluvial profiles. The increase was related to the considerable emission of these elements to the environment starting from the 1950s. K. Gillijns et al. (2005) assumed that the intensive use of phosphorus fertilisers in Belgium began after World War II, and established the present-day accumulation rates for material in the bottom of a closed depression used for agricultural purposes. Recently, T. Zádorová et al. (2013) used DDT and heavy metal content to estimate the sedimentation rate of colluvial sediments in the Czech Republic.
4In the case of periodic emissions or inputs to the environment related to a specifically local source, the age of the particular layers can be estimated with accuracy of several years (Ritchie and McHenry, 1990; Froehlich and Walling, 1992; Walling and He, 1997; Łokas et al., 2006). However, usually the time scope of precise analyses ranges between 50 and 100 years, which approximately corresponds to the duration of intensive human-induced geochemical impact on the environment. In areas where the development of mining or metallurgical plants occurred earlier, “geochemical dating” may be carried out within a time frame of 1000 years (Matschullat et al., 1997).
5In the study, the vertical distribution of heavy metals and phosphorus concentration as well as 137Cs activity were analysed in the profiles of slope and fluvial sediments. Profiles were located in the western part of the Lublin Upland, eastern Poland (fig. 1). In addition, results of 36 radiocarbon datings were used to estimate the sedimentation rate in a longer time frame (thousands of years). On this basis, an attempt was made to estimate the sediment deposition rate in various time frames, which made it possible to determine the trends in the changes in the sediment accumulation rate during the last several thousand years. The key objective of the study was to present general patterns; the determinants and values of the sedimentation rate for the individual profiles were not investigated in detail. It should be stressed that such data collation has not been performed for the loess areas of E Poland so far.
Fig. 1 – Location of the profiles studied.
Fig. 1 – Localisation des coupes étudiées.
1: loess; 2: profiles.
1 : lœss ; 2 : coupes.
6The profiles analysed are located in the western part of the Lublin Upland, mostly within the loess-covered Nałęczów Plateau (fig. 1). The bedrock here features lithologically diverse rock strata: carbonate and carbonate-siliceous rocks of the Upper Cretaceous and Palaeocene, overlain by Tertiary and Quaternary deposits. Quaternary sediments developed as sands, glacial tills, silts, loams and river gravels. The thickness of the loess cover ranges from a few to 30 m. Alluvial sediments and peats occur in the valley bottoms and closed depressions. The thickness of Holocene sediments here ranges from a few to a dozen or so metres, including as much as 3.5 to 5 m of the youngest sediments related to the anthropogenic erosion of loess areas (Nakonieczny, 1967).
7In the western part of the Lublin Upland, there are several plateaus intersected by sparse river valleys and a dense network of dry valleys. The Bystrzyca, Bystra, and the Wyżnica belong to the biggest rivers of this mesoregion (fig. 1). Loess areas are characterised by relative heights of 40 m to 90 m within one square kilometre, a large share of steep slopes and a dense gully network. In the western part of the Nałęczów Plateau, gully density locally exceeds 10 km/km2.
8The annual rainfall is 550 to 600 mm. The average summer rainfalls (220-240 mm) within the area are two or three times bigger than the average spring or autumn rainfalls. Flash floods are caused by summer rainfalls of 50-100 mm within 1-2 hours. Such events recur every 20-30 years. Floods related to thaw occur much more frequently (Rodzik et al., 2009).
9The soil cover of the study area has a marked mosaic-like character (Klimowicz and Uziak, 2001). Cambisols and Luvisols predominate, while alluvial soils occur in river valleys. The western part of the Lublin Upland is a typical agricultural region whose land use structure is dominated by arable lands (60%), with a considerably smaller share of forests (15% to 20%) and grasslands. The distinct patchwork of land use is a characteristic feature of loess areas (fig. 2). On average, 30 land use patches occur within one square kilometre (Baran-Zgłobicka and Zgłobicki, 2012). The average concentrations of heavy metal in sediments are low (tab. 1). Higher concentrations occur in the youngest, top horizons, which enables the use of chemostratigraphic methods.
10The area is also characterised by quite intense erosion processes facilitated by the environmental conditions, i.e. numerous loess covers, diverse land relief, a dense gully network, 1-2 km2 in average, up to 10 km2 (fig. 3), and agricultural land use (Schmitt et al., 2006; Zgłobicki and Rodzik, 2007). In the past, gullies played a very important role in the production of sediment (Dotterweich et al., 2012). In modern times, the role of gullies is definitely more limited because of the forest cover (Rodzik et al., 2009). The present-day erosion rate within cultivated slopes ranges from 2 mm/a to 8 mm/a (Zgłobicki, 2002).
Fig. 2 – Present-day land use in the western part of Lublin Upland.
Fig. 2 – Utilisation actuelle du sol dans l’ouest du Plateau de Lublin.
1: arable lands; 2: orchards; 3: meadows; 4; forests; 5: buildings; 6: rivers and lakes.
1 : terres cultivables ; 2 : vergers ; 3 : prairies pâturées ; 4 : forêts ; 5 : bâti ; 6 : lacs et rivières.
Prepared by L. Gawrysiak on the base of CORINE Land Cover Map 2006.
Préparé par L. Gawrysiak à partir des données cartographiques CORINE Land Cover, 2006.
Fig. 3 – Gully systems in the central part of Nałęczów Plateau.
Fig. 3 – Réseau de ravines au centre du Plateau de Nałęczów.
Tab. 1 – Share of samples exceeding the geochemical background.
Tab. 1 – Part des échantillons dépassant le niveau géochimique de référence.
Type of sediments
|
Cd
|
Cu
|
Pb
|
Zn
|
Mean
|
Colluvia
|
28
|
66
|
66
|
48
|
50
|
Alluvial sediments (agricultural areas)
|
27
|
89
|
89
|
10
|
53
|
Alluvial sediments (urban areas)
|
83
|
83
|
98
|
75
|
84
|
Mean
|
35
|
62
|
66
|
39
|
|
Geochemical background after Zgłobicki et al., 2011.
Données géochimiques d’après Zgłobicki et al., 2011.
11A vertical distribution of geochemical markers in 53 colluvial and alluvial profiles were analysed (tab. 2). The profiles differed in terms of grain-size distribution, chemical properties and morphological location. The location of the profiles was selected so as to provide a basis for estimations of regional character (primarily for loess areas). Some of the profiles were described in the published papers (Zgłobicki et al., 2011), but the sedimentation rates were not calculated. The profiles, 1 m to 5 m thick, consisted mostly of loams, more rarely sandy silts or silty sands (tab. 3). In a few cases, the lower parts of profiles located in bottoms of river valleys consisted of peat. Colluvial profiles were taken from the lower slope locations, closed depressions and bottoms of small dry valleys. Alluvia of small and medium rivers typical for the loess areas were analysed (mean discharge: 1 m3/s to 5 m3/s). Sediments of big, transition rivers – Vistula, Bug, were not studied.
12The content of heavy metals (Cd, Cu, Pb, and Zn) was determined by means of atomic absorption spectroscopy (MCSU Analytical Laboratory), while total phosphorus was determined spectrophotometrically using the ascorbic acid method (MCSU Department of Soil Science). 137Cs activity was measured at the MCSU Department of Radiochemistry and Colloid Chemistry (Silena gamma spectrometer). Most of the 14C datings used in the study were carried out at the Gliwice Radiocarbon Laboratory, the Kiev Radiocarbon Laboratory and Kiel Laboratory. The dating was performed for charcoal, wood, peat and, in a few cases, organic matter originating from the humus horizons. The OxCal 3.9 program (developed by Oxford Radiocarbon Accelerator Unit) was used for date calibration (the cal. 2σ dates were applied).
13The present-day sedimentation rate was estimated based on the depth of layers characterised by a clearly higher concentration of the specific markers (fig. 4) correlated with the time-specific stages of anthropogenic pressure (emission of elements and isotopes to the environment). The average sedimentation rate was calculated according to the formula (1):
SR=D/T (1)
with SR: average sedimentation rate; D: depth of the correlative sediment layer; T: time elapsed from the deposition of the layer.
14The sedimentation rate for the long time frame was determined in a similar way, using 14C dating. All published radiocarbon datings from the western part of Lublin Upland were analysed. The vertical variation in caesium, phosphorus and heavy metal content in the profiles was used to estimate the present-day sedimentation rate. Based on the marked increase in the concentration of 137Cs found in the deepest layer, it was assumed that the layer dated back to the 1960s. The subsequent concentration maximum dated back to the mid-1980s, i.e. the Chernobyl accident (Stach, 1991; Zgłobicki, 2002). In the case of phosphorus, it was assumed that a highest concentration of this element in the soil occurred in the 1970s and was related to the most intensive use of phosphorus fertilisers. Phosphorus fertiliser consumption in Poland was rising from ca. 3 kg/ha (before World War II) to ca. 50 kg/ha in the late 1970s. At the turn of the 1990s, the consumption fell along with the deregulation of prices (Dach and Starmans, 2005), and currently stands at ca. 20 kg (P2O5)/ha. In view of the above, sediments dating back to the 1970s show the highest phosphorus content.
15In profiles located in the area of Neolithic settlements, it was possible to estimate the sedimentation rate in the bottom of dry valleys and closed depressions based on the depth at which high phosphorus content occurred (Lambert, 1998). The 1970s were recognised as the period of the highest heavy metal input into the environment. In that period, the most intensive lead emissions into the atmosphere occurred as a result of petrol combustion (Clemens and Stahr, 1994; Renberg et al., 2002). Detailed analyses of the atmospheric deposition of lead, obtained from the analyses of Alpine ice cores, show a 25-fold increase of lead content in the 1970s compared with the 17th century, followed by its decrease in the years 1970 to 1994 (Schwikowski et al., 2004). Heavy metal emissions in Poland have also been falling since the 1980s (Zgłobicki, 2008). Sediments occurring in valley bottoms are enriched with elements contained in the eroded material. It was assumed that the layers with the highest heavy metal and phosphorus content in the profiles dated back to the 1970s whereas the layer with the highest 137Cs content dated back to the mid-1980s (fig. 4). The average present-day sedimentation rates (for the last 35 years), based on the mentioned assumption, were calculated for the specific profiles.
Fig. 4 – Vertical distribution of markers in profile H-3 profile.
Fig. 4 – Variation verticale de la concentration des marqueurs sur la coupe H-3.
Tab. 2 – Profiles by genetic type of sediments.
Tab. 2 – Tableau récapitulatif des coupes étudiées selon la nature des sédiments.
Type of sediments
|
Number of profiles
|
Number of samples
|
Colluvia
|
30
|
316
|
Alluvial sediments (agricultural areas)
|
10
|
142
|
Alluvial sediments (urban areas)
|
13
|
221
|
Total
|
53
|
680
|
Tab. 3 – Basic, averaged physical properties of the sediments studied.
Tab. 3 – Caractéristiques physiques élémentaires (moyenne) des sédiments étudiés.
Type of sediments
|
Organic matter content
[%]
|
pH
|
Content of grains: 0.05-1 mm
[%]
|
Content of grains: 0.05-0.002 mm [%]
|
Content of grains: <0.002 mm [%]
|
Colluvia
|
1.3
|
5.8
|
29
|
62
|
10
|
Alluvial sediments (agricultural areas)
|
3.3
|
7.1
|
26
|
65
|
9
|
Alluvial sediments (urban areas)
|
7.8
|
7.0
|
43
|
49
|
4
|
16In most cases, the sediment accumulation rate calculated based on the vertical distribution of heavy metals, phosphorus and caesium did not exceed 3 mm/a. It was between 3 and 10 times higher than the average colluvial and alluvial sedimentation rates calculated based on radiocarbon dating results (tab. 4 and tab. 5). For profiles sampled from the riverbanks of the rivers Bystrzyca and Wyżnica , ‘geochemical dating’ indicated an even greater accumulation rate of up to 30 cm per 30 years. It has to be noted, however, that since 10 cm layers were analysed, the sedimentation rate for some profiles may have been overestimated, and less than 10 cm of sediments accumulated in some valleys during the last 30 years.
17The sedimentation rates during the last few thousand years, estimated according to 14C dating results, reaches the order of a about 0.5 mm/a, for the last 1000 years it was about 1 mm/a (tab. 4 and tab. 5). The lowest accumulation rate was found for the bottom of the Bystrzyca valley, upstream of and within the city of Lublin: 1.2-3.8 cm per 100 years. In the case of gullies intersecting loess areas with diverse relief, the alluvial sedimentation rate may reach the order of 25 mm/a (tab. 4).
18The sedimentation rate in the long time frame was estimated based on the vertical variation of phosphorus content in sediments deposited in closed depressions near the archaeological sites. It was established that the intensity of this process was 0.2 mm/a to 0.3 mm/a during the last 5 to 10 thousand years.
19The collation of all data obtained during the study made it possible to determine the trends in the changes in valley-bottom sedimentation rate in the study area in the short, medium and long time frame (tab. 4, fig. 5, and fig. 6). It should be remembered that present-day data reflect the actual processes whereas the sedimentation rate for long time frames, in the order of thousands of years, is the product of erosion and sedimentation processes (of various intensity). Therefore, these data cannot be compared directly with one another. The long-term sedimentation rate is a reference point for present-day data.
20A positive balance of material was found in all profiles: sediments were accumulating in the bottoms of dry valleys and river valleys. Investigations conducted so far explicitly indicate that the amount of material delivered from the catchment to the valley bottom is higher than the amount of material discharged. This is confirmed by the soil profiles building up in the valley bottoms (Klimowicz and Uziak, 2001; Zgłobicki and Rodzik, 2007; Zgłobicki, 2008). The transport of material from valley bottoms occurs exclusively during exceptionally intense rainfalls and thaws (Rodzik et al., 2009).
21The 14C datings performed indicate that the thickness of the sediments varies spatially. In the case of small river valleys, between 12 cm and 500 cm of alluvial sediments have accumulated during the last 1000 years (tab. 5). Colluvia are represented by mineral sediments, analogously to the upper parts of alluvial profiles. Organic deposits in river valleys occur at the depth of more than 100 cm. The process of organic matter (peat) accumulation ended in the western part of the Lublin Upland around the 10th century. The 14th century saw the development of settlements under Magdeburg Law as well as the emergence of strip-fields with long strips of land stretching from valley floors to hilltops. It was then that the permanent deforestation of loess-covered areas began. Human pressure on the environment, as manifested in changes of the land cover, was becoming ever more intense. Approximately from the 16th century onwards, the anthropogenic components of landscape (agricultural land, settlements) began to dominate over the natural components. The last stage of intense changes to landscape, i.e. the expansion of agricultural land at the expense of forest areas, occurred in the 19th and 20th century as a result of the industrial revolution. The introduction of root vegetable crops (19th century) and the mechanisation of agriculture (20th century) were important factors influencing the dynamics of landscape transformations (Maruszczak, 1988).
22Afterwards, mineral sediments accumulated in valley bottoms, which can be related to the beginning of intensive transformations of the environment that lead to intensified erosion in drainage basins and discharge of material into fluvial systems (Maruszczak, 1988; Buraczyński, 1989/1990; Schmitt et al., 2006).
23Comparison of the present-day sedimentation rates to the long-term data suggests that during the past few thousand years, the sedimentation rates increased by an order of magnitude (tab. 4 and tab. 5), which results primarily from changes in land use and intensification of erosion processes (Maruszczak, 1988; Starkel, 1988; Schmitt et al., 2006; Dotterweich, 2008). H. Maruszczak (1988) estimates that ca. AD 1000 agricultural land occupied as little as 10% of the territory of the present-day Lublin region, while in modern times it covers more than 80% (fig. 7). B. Baran-Zgłobicka and W. Zgłobicki (2012) report that the forest cover in loess areas of SE Poland has fallen from 30% to 20-10% during the last 150 years.
24The average present-day colluvial sediment deposition rate is double the rate for alluvial sediments (fig. 5 and fig. 6), which confirms that large amounts of eroded material accumulated in the lower parts of slopes and bottoms of dry valleys (Święchowicz, 2002; Boardman and Poesen, 2006). This has mainly resulted from tillage erosion (Zgłobicki, 2002).
25When analysing the sedimentation rate data, presented in the paper, one has to consider the following determinants influencing the reliability of the results obtained: (i) Different amounts of data were available for different periods; the largest amount was available for modern times. (ii) Sedimentation occurs periodically, not continually. In the case of present rates (data for the last 35 years), there is a risk of overestimation of the sedimentation rate (due to extreme events). The sedimentation rate becomes averaged out in longer time frames. (iii) Radiocarbon dating yielded time frames, not single dates. The likelihood of the multiple re-deposition of the organic matter for which dating is performed (particularly in the case of gully colluvia) presents another difficulty. (iv) The sediments studied, especially colluvia, were sometimes characterised by low heavy metal concentrations, which, in some cases, reduced their usefulness as stratigraphic markers.
26Some authors point to the fact that the process of vertical migration of heavy metals accumulated in the mid-19th century may reach the order of a few to more than 100 cm in the case of rivers where sandy alluvial sediments predominate and where channel incision occurs (Hudson-Edwards et al., 1998). It should be stressed, however, that in the case of the sediments analysed, the mobility of geochemical markers should not be very high, considering: (i) the lack of a clear trend towards the downward erosion of channels; (ii) a large share of fine fractions conducive to the permanent binding of markers; (iii) a short period elapsed from their deposition (30 to 50 years).
27Analysing the vertical distribution of markers in profiles is not always sufficient for their straightforward interpretation. For example the maximum contents of the specific heavy metals occurred at various depths (tab. 6). In 65% of cases, it was possible to obtain correspondence between the specific markers. In the remaining 35%, the specific markers provided inconsistent data on the age of the particular layers. This may result from the varied significance of anthropogenic input for the particular elements or from limited vertical migration.
28Since the results presented in this study are based on analyses of a considerable number of profiles, the author believes that the reliability of these results is relatively high. The data obtained were primarily used to determine the general trends in sedimentation rate changes in loess areas of E Poland. No attempt was made in this study to correlate the obtained results with the data for the particular catchments (lithology, topography, soils, land use).
29The sedimentation rate calculated here conforms to the figures published in geological and geomorphological literature. However, the possibility of direct comparisons with figures for the loess areas of E Poland is limited due to the scarcity of such data. For example, based on the results of a few 14C datings and sedimentological analyses, W. Zgłobicki and J. Rodzik (2007) estimated the sedimentation rate in the bottoms of river valleys in the Nałęczów Plateau at 1.3 mm/a during the last few hundred years. In the case of the bottoms of periodically drained valleys, the rate ranges from 2.9 mm/a to 7.3 mm/a, while figures obtained during levelling measurements carried out in the years 1985 to 1978 indicate a moderate rate of sedimentation in the bottom of a dry valley to the order of 6.6 mm/a (Mazur and Pałys, 1985).
30The figures obtained in this study were also compared with data for other areas. In the case of fluvial sediments, D. Ciszewski (2003) estimated the present-day sedimentation rate for the middle Odra at 1 mm/a to 20 mm/a. Similar figures were obtained for the valley of the upper Warta: 11 mm/a (at the edge of the channel) and ca. 5 mm/a (10 m to 20 m away from the channel; Łokas et al., 2006). T. Matys Grygar et al. (2012) reported a very small increase of the flood-plain sedimentation rate in the last 1300 years (Morava River): 2-3 mm/a in AD 700 to 3-4 mm/a in AD 2000. However, the flood sedimentation rates in the oxbow lake of the Morava River presented by O. Bábek et al. (2012) are much bigger: 12-61 mm/a.
31T. Rommens et al. (2005) estimated the sedimentation rate within a small agriculturally used drainage basin (a loess area in Belgium) in the Holocene period at 0.13 mm/a. J. Matschullat et al. (1997) indicated an increase in the sedimentation rate of off-channel sediments in the Harz mountain range from 1 mm/a to 4 mm/a during the past 1000 years. Similar patterns were observed by A. Lang and S. Hönscheidt (1999) based on the OSL dating of slope sediments. During the last 2000 years, the sedimentation rate at selected sites in southern Germany increased from 0.2 mm/a to 1.8 mm/a. A higher sedimentation rate in inter-moraine depressions and closed depressions was reported by M. Frielinghaus and W.G. Vahrson (1998). During the last 600 years, the average rate was 1 mm/a to 2 mm/a, reaching 5 mm/a in the 1960s. Studying the accumulation of slope sediments in the Suwałki Lakeland, E. Smolska (2007) found that its rate increased from 0.2 mm/a a few thousand years ago to nearly 3 mm/a between the 12th and 14th century AD. A very high sedimentation rate of 30 mm/a during the last 50 years was reported for the loess areas in Germany (Kadereit et al., 2010) and the Czech Republic (Zádorová et al., 2013).
Fig. 5 – Colluvial sediments deposition rate in various time frames.
Fig. 5 – Taux de sédimentation dans les colluvions à différentes périodes.
Dots indicate average values and do not correspond to number of samples/dates.
Les points indiquent les valeurs et ne correspondent pas au numéro des échantillons/datations.
Fig. 6 – Alluvial sediments deposition rate in various time frames.
Fig. 6 – Taux de sédimentation dans les alluvions à différentes périodes.
Dots indicate average values and do not correspond to number of samples/dates.
Les points indiquent les valeurs et ne correspondent pas au numéro des échantillons/datations.
Fig. 7 – Landscape changes in Lublin region during the last 1000 years.
Fig. 7 – Modifications du paysage dans la région de Lublin au cours du dernier millénaire.
After Maruszczak 1988.
D’après Maruszczak, 1988.
Tab. 4 – Slope and fluvial sediment deposition in the western part of the Lublin Upland.
Tab. 4 – Tableau récapitulatif des taux de sédimentation sur les versants et le long des cours d’eau dans la partie ouest du Plateau de Lublin.
Index
|
Type of sediment
|
Number of profiles
|
Time frame of sedimentation [years]
|
Source
|
Calculated sedimentation rate [mm/a]a
|
14C
|
gully sediments
|
4
|
4 000
|
Schmitt et al. (2004)
|
0.1
|
P
|
colluvia
|
4
|
10 000 – 5 000
|
Zgłobicki (2008)
|
0.2-0.3
|
14C
|
colluvia
|
3
|
7 000 – 3 000
|
Kołodyńska-Gawrysiak (unpublished data)
|
0.3-0.5
|
14C
|
gully sediments
|
4
|
500
|
Schmitt et al. (2006)
|
2.0-9.6
|
14C
|
gully sediments
|
1
|
500
|
Schmitt et al. (2004)
|
3.0
|
heavy metals
|
colluvia
|
13
|
30
|
Zgłobicki (unpublished data)
|
3-6
|
137Cs
|
colluvia
|
2
|
30
|
Zgłobicki (unpublished data)
|
10
|
137Cs
|
colluvia
|
15
|
20
|
Zgłobicki (2002)
|
3-18
|
137Cs
|
gully sediments
|
5
|
30
|
Zgłobicki (unpublished data)
|
5-25
|
14C
|
alluvia
|
11
|
15 000 – 1 500
|
Zgłobicki (2008)
|
0.1-0.9
|
14C
|
alluvia
|
1
|
11 000
|
Maruszczak and Bałaga (1981)
|
0.3
|
14C
|
alluvia
|
1
|
6 000
|
Superson et al. (2003)
|
0.8
|
14C
|
alluvia
|
7
|
1 000
|
Zgłobicki (2008)
|
0.8-6.3
|
14C
|
alluvia
|
2
|
3 500 – 1 000
|
Superson and Zgłobicki (2005)
|
1.4-2.9
|
P
|
colluvia
|
4
|
30
|
Zgłobicki (unpublished data)
|
3-5
|
P
|
alluvia
|
5
|
30
|
Zgłobicki (unpublished data)
|
3-9
|
heavy metals
|
alluvia
|
17
|
30
|
Zgłobicki (unpublished data)
|
3-16
|
137Cs
|
alluvia
|
3
|
30
|
Zgłobicki (unpublished data)
|
5-10
|
a Calculation made according to the equation 1.
a Calculs conformes à l'équation 1.
Tab. 5 – Comparison of sedimentation rates for different time periods in selected profiles (14C data available).
Tab. 5 – Comparaison des taux de sédimentation au cours de différentes périodes dans les coupes sélectionnées (en fonction des données 14C disponibles).
Profile
|
Depth of sampling [cm]
|
Calibrated radiocarbon age1
|
Sedimentation rate in the last 8000 years [mm/a]
|
Sedimentation rate in the last 1000 years [mm/a]
|
Present-day sedimentation rate [mm/a]
|
H-1
|
110
|
AD 50-420
|
0.5-0.7
|
-
|
3.0
|
H-1
|
170
|
810-480 BC
|
0.6-0.7
|
-
|
H-3
|
150
|
AD 1170-1400
|
-
|
1.9-4.0
|
10.0
|
H-3
|
230
|
1500-1190 BC
|
0.6-0.7
|
-
|
Ks-6
|
190
|
3340-2910 BC
|
0.3-0.4
|
-
|
3.0
|
L-1
|
140
|
6251-5998 BC
|
0.2
|
-
|
-
|
L-2
|
115
|
7195-6686 BC
|
0.1
|
-
|
-
|
N-1
|
95
|
AD 810-1160
|
-
|
0.8-1.2
|
3.0
|
N-1
|
200
|
1000-520 BC
|
0.6-0.8
|
-
|
Nd-1
|
50
|
AD 890-1220
|
-
|
0.4-0.6
|
-
|
Nd-1
|
200
|
6480-6210 BC
|
0.2
|
-
|
-
|
O-1
|
90
|
AD 990-1280
|
-
|
0.9-1.2
|
3.0
|
O-1
|
195
|
330-200 BC
|
0.8
|
-
|
P-1
|
55
|
AD 100-700
|
0.3-0.4
|
-
|
3.0
|
P-1
|
200
|
5640-5510 BC
|
0.2
|
-
|
R-2
|
370
|
AD 765-1025
|
-
|
3.0-3.7
|
5.0
|
W-1
|
500
|
AD 1020-1260
|
-
|
5-7
|
-
|
“-“ no data; 1 after Zgłobicki (2008).
Tab. 6 – The depth of layers with the highest content of the elements studied.
Tab. 6 – Profondeur des couches montrant la plus forte teneur en éléments étudiés.
Profile (cm)
|
Cd
|
Cu
|
Pb
|
P
|
137Cs
|
Colluvial
|
Dp-2
|
0-10
|
0-10
|
0-10
|
-
|
-
|
Kc-1
|
195-205
|
5-15
|
5-15
|
-
|
-
|
Kl-1
|
0-10
|
60-70
|
10-20
|
|
|
Kl-2
|
10-20
|
0-10
|
10-20
|
100-110
|
-
|
Kn-1
|
5-10
|
5-10
|
85-90
|
-
|
-
|
Kr-1
|
-
|
90-100
|
30-40
|
140-150
|
-
|
Ks-4
|
80-90
|
20-30
|
0-10
|
0-10
|
-
|
N-2
|
70-80
|
0-10
|
0-10
|
|
|
P-2
|
-
|
100-110
|
100-110
|
0-10
|
10-20
|
W-2
|
75-80
|
175-180
|
175-180
|
-
|
-
|
H-3
|
20-30
|
0-10 (30-40)
|
20-30
|
10-20
|
20-30 (40-50)
|
Ks-3
|
-
|
30-40
|
10-20
|
0-10
|
-
|
Kn-2
|
5-10
|
50-60
|
5-10
|
-
|
-
|
R-1
|
5-10
|
5-10
|
5-10
|
5-10
|
5-10
|
Sn-3
|
0-10
|
40-50
|
20-30
|
0-10 (50-60)
|
-
|
Alluvial
|
P-1
|
-
|
0-10
|
30-40
|
0-10
|
0-10
|
R-2
|
10-20
|
0-10
|
10-20
|
0-10
|
0-10 (40-50)
|
Sn-1
|
20-30
|
40-50
|
0-10 (30-40)
|
-
|
-
|
Sn-2
|
5-10
|
5-10
|
5-10
|
-
|
-
|
N-1
|
0-10
|
0-10
|
0-10
|
-
|
-
|
W-1
|
-
|
10-20
|
0-10
|
-
|
-
|
H-1
|
0-10
|
20-30
|
0-10
|
-
|
-
|
H-2
|
5-10
|
45-50
|
45-50
|
-
|
-
|
Ks-1
|
30-40
|
30-40
|
10-20
|
-
|
-
|
Ks-2
|
0-20
|
20-40
|
60-80
|
-
|
-
|
Ks-5
|
20-30
|
20-30
|
10-20
|
20-30
|
-
|
Ks-6
|
5-10
|
5-10
|
5-10
|
-
|
-
|
O-1
|
5-10
|
5-10
|
15-20
|
-
|
-
|
Pt-1
|
0-10
|
10-20
|
10-20
|
0-10
|
-
|
Pt-1a
|
10-15
|
10-15
|
5-10
|
-
|
-
|
Pt-2
|
0-10
|
10-20
|
30-40
|
-
|
-
|
32(i) The application of several dating methods made it possible to determine the trend in sedimentation rate changes in the loess areas of E Poland.
33(ii) It was found that the sedimentation rate increased considerably from 0.1-0.7 mm/a during the last 8000 years to 3-25 mm/a in present times.
34(iii) The average present-day colluvial sediment deposition rate is double the rate for alluvial sediments, which results from the poor connectivity between slope and fluvial systems.
35(iv) A straightforward interpretation of chemostratigraphic dating results was possible for approximately 65% of the profiles. The results for the remaining 35% were ambiguous.
36(v) There is a clear relation between the sedimentation rates and the changes in land use of loess areas.
Author would like to thank the anonymous reviewers for their valuable comments and suggestions to improve the quality of the paper.