habitats in the BNP were developed as a result of an interplay of correlations
between river flooding, depth of groundwater table, climate pressure and vegetation
development within the three topographically distinct basins, i.e. northern (upper),
central and southern (lower) along the 60 km stretch of the Biebrza River (Os ´wit
1991). The Park area is located in three climatic zones which conform more or less
to the three basins of the river (Liszewska 2011). The three zones vary significantly
in climatic conditions, and especially, in temperature and precipitation distribution.
The northern basin is cooler and moister than the southern one, while the central
basin has transitional climatic conditions. For these three climatic zones changes in
basic climatic parameters (precipitation, temperatures) were determined for the
period of the last 50 years (1951–2000) and climate forecast until the year 2100
was made. Soil properties and plant communities were also studied within the
above zones along the established transects. The results obtained along with the
literature data concerning sensitivity of soil and vegetation parameters to climate
change were used as a basis for selecting characteristics which are most sensitive to
climate change driven pressures and for determining variability scales for every
property within the area examined. In this way, indicators most sensitive to climate
change, could be established and validated with respect to their suitability for
management support.
In the BNP there dominate peat soils mineralised to various degrees. The peat
mineralisation degree may be determined using the soil carbon content as a metric.
It was found that soil carbon content fluctuates from 50 to 40 % in natural peats in
the northern park zone, to less than 20 % in degraded peat soils which occur mainly
in the southern climatic zone. In the transitional zone there occur peat soils of
various degree of mineralisation where carbon content constitutes 40–30 % in
decaying marshy peats and about 30–30 % in marsh soils. Taking into account
the results of study in the BNP as well as the literature data on SOM sensitivity to
climate change and the threat of CO 2 release to the atmosphere we adopted that it is
the carbon accumulation in organic soils that provides for a most sensitive characteristics of the effects of climate change and a good indicator of climate changeinduced changes in wetland habitats. To assess the indicatory strength of the soil
carbon content, the correlational and functional relationships were statistically
determined between this content and the remaining soil attributes such as Soil
Organic Carbon (SOC), Soil Organic Nitrogen (SON), SOM, Dissolved Organic
Nitrogen (DON), Cation Exchange Capacity (CEC), Bulk Density (BD), Soil Water
Content (SWC), Maximal Water Holding Capacity (MWHC) and Field Water
Capacity (FWC) (Tables 6.3 and 6.4).
Close relationships were found between all these properties what is evidenced by
the high values of correlation coefficients, though the most significant correlation
was determined between the soil carbon content and the remaining soil properties.
The significance of correlation was corroborated by calculating Pearson’s correlation coefficients between each of the soil properties analysed (Table 6.5).
A more detailed description of the relationships between the soil properties was
provided on the basis of regression equations. The values of determination coefficients (R
2 ) > 0.7 were characteristic of the relationships between the contents of
86
J. Sienkiewicz et al.
between river flooding, depth of groundwater table, climate pressure and vegetation
development within the three topographically distinct basins, i.e. northern (upper),
central and southern (lower) along the 60 km stretch of the Biebrza River (Os ´wit
1991). The Park area is located in three climatic zones which conform more or less
to the three basins of the river (Liszewska 2011). The three zones vary significantly
in climatic conditions, and especially, in temperature and precipitation distribution.
The northern basin is cooler and moister than the southern one, while the central
basin has transitional climatic conditions. For these three climatic zones changes in
basic climatic parameters (precipitation, temperatures) were determined for the
period of the last 50 years (1951–2000) and climate forecast until the year 2100
was made. Soil properties and plant communities were also studied within the
above zones along the established transects. The results obtained along with the
literature data concerning sensitivity of soil and vegetation parameters to climate
change were used as a basis for selecting characteristics which are most sensitive to
climate change driven pressures and for determining variability scales for every
property within the area examined. In this way, indicators most sensitive to climate
change, could be established and validated with respect to their suitability for
management support.
In the BNP there dominate peat soils mineralised to various degrees. The peat
mineralisation degree may be determined using the soil carbon content as a metric.
It was found that soil carbon content fluctuates from 50 to 40 % in natural peats in
the northern park zone, to less than 20 % in degraded peat soils which occur mainly
in the southern climatic zone. In the transitional zone there occur peat soils of
various degree of mineralisation where carbon content constitutes 40–30 % in
decaying marshy peats and about 30–30 % in marsh soils. Taking into account
the results of study in the BNP as well as the literature data on SOM sensitivity to
climate change and the threat of CO 2 release to the atmosphere we adopted that it is
the carbon accumulation in organic soils that provides for a most sensitive characteristics of the effects of climate change and a good indicator of climate changeinduced changes in wetland habitats. To assess the indicatory strength of the soil
carbon content, the correlational and functional relationships were statistically
determined between this content and the remaining soil attributes such as Soil
Organic Carbon (SOC), Soil Organic Nitrogen (SON), SOM, Dissolved Organic
Nitrogen (DON), Cation Exchange Capacity (CEC), Bulk Density (BD), Soil Water
Content (SWC), Maximal Water Holding Capacity (MWHC) and Field Water
Capacity (FWC) (Tables 6.3 and 6.4).
Close relationships were found between all these properties what is evidenced by
the high values of correlation coefficients, though the most significant correlation
was determined between the soil carbon content and the remaining soil properties.
The significance of correlation was corroborated by calculating Pearson’s correlation coefficients between each of the soil properties analysed (Table 6.5).
A more detailed description of the relationships between the soil properties was
provided on the basis of regression equations. The values of determination coefficients (R
2 ) > 0.7 were characteristic of the relationships between the contents of
86
J. Sienkiewicz et al.