Assessing the stream water quality dynamics in connection with land use in agricultural catchments of different scales

Abstract

The ecological status of many surface waters in the Czech Republic is poor, mainly due to still relatively high discharges of N substances especially from agriculture. High nitrate values in the streams situated particulary in basins of drinking water reservoirs invoke the neccesity for the precise detection of diffuse pollution areas to enable the setting of the appropriate land management strategies or relevant measures. We introduce a simple method for estimating the changes of nitrate concentrations in surface waters regarding the land use modification. Stream and drainage water nitrate concentrations in prevailingly agricultural catchments of three different scales located in the Crystalline complex of the Czech massif were included in this study. Water quality samples were collected through the years 1992–2006 at monthly and bi-monthly intervals. For the catchment land use analysis, the satellite images LANDSAT 7 (CORINE Land Cover) and digitised cadastre maps of the land register were processed using ESRI ArcMap GIS; both sources corrected by field survey. We demonstrate on three different basin – scale studies a strong relation between the arable land ratio within a catchment and the coherent stream water nitrate concentration. The results acquired from all the evaluated catchments showed that every 10% decrease of ploughed land proportion in a catchment lowers the nitrate concentration C90 value (90% probability of non-exceedance) in average by 6.38 mg/l.

Long-term improvement in surface water quality after land consolidation in a drinking water reservoir catchment

“…Krause et al (2008) described similar results in catchments of Estonia following a reduction in application of fertilizers, an increase in the area of permanent grassland, and implementation of better farm management practices. Several other studies (Worral & Burt 1999;Ferrier et al 2001;Lenhart et al 2003;Matějíček et al 2003;Buck et al Oenema et al 2005;Poor & McDonnell 2007;Fučík et al 2008) found the relationship between nutrient concentration in water and the land cover, especially the proportion of arable land, in the same range as in our research. All water quality parameters monitored in the two closing profiles (S1 and S2) responded positively to the increased grassland area and the reduced fertilizer use, experiencing a decline in concentrations and markedly narrower ranges of the values measured (Tables 3 and 4).…”

“…Namely, the extent of arable land should be reduced in favour of permanent grassland. This pertains in particular to tile-drained lands, because they represent an enhanced risk of nonpoint pollution of surface waters and groundwater with nutrients and pesticides (Doležal & Kvítek 2004;Lexa et al 2006;Tiemeyer et al 2006;Fučík et al 2008).…”

The Location and Extent of Systematic Drainage in Relation to Land Use in the Past and at Present and in Relation to Soil Vulnerability to Accelerater Infiltration in the Protected Landscape Area Železné Hory

“…In the studied area, these soils (at high or very high risk of accelerated infi ltration) are localized in 35% of the territory. They are not suitable for use as arable land and should be transformed into the category of permanent grass covers (Fučík et al, 2008;Fučík et al, 2010;Kvítek et al, 2009). …”

Environmental implications of animal wastes pollution on agricultural soil and water quality

“…This slow release conserves the nutrients and allows them to be available to the crop throughout the growing season. However, since the rate of such releases is uncontrollable, this can be viewed as a disadvantage as well (Fučík et al 2008). Finally, the economic value of manure can be determined by its nutrient content (N, P, and K) and the material can be sold as commercial fertilizer.…”