1 / 23

José Salomão Silva Universidade de Brasília Daniel Markewitz University of Gerogia

Universidade de Brasília Departamento de Ecologia. Effects of different land cover on chemical characteristics of streams and flow components in the Cerrado region. José Salomão Silva Universidade de Brasília Daniel Markewitz University of Gerogia

brielle-parsons
Télécharger la présentation

José Salomão Silva Universidade de Brasília Daniel Markewitz University of Gerogia

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Universidade de Brasília Departamento de Ecologia Effects of different land cover on chemical characteristics of streams and flow components in the Cerrado region José Salomão Silva Universidade de Brasília Daniel Markewitz University of Gerogia Mercedes Bustamante Universidade de Brasília Richard Zepp US - EPAAlex Krusche Universidade de São Paulo/CENA Roger Burke US - EPA Laerte Guimarães Universidade Federal de Goiás/LAPIG

  2. BrazilianSavanna “Cerrado” • 2ndmostextensiveplantformationoftheLatin America • 2.000.000 km2; • 24% oftheBrazilianterritory; • Where are formed the main basin: • Paraná /Paraguai – 71% • Araguaia /Tocantins – 71% • São Francisco – 94%

  3. Braziliansavanna “Cerrado” • Climate • Precipitation ranges from 750 - 2000mm • Soils • Mostly dystrophic; • About 46% are Oxisols (low pH, high Al, clayey); • 15% are sandy soils.

  4. Open scrubland Open grassland “Campo sujo” “Cerrado ralo” “Cerrado típico” <1% <5% 5-20% Canopy cover index 20-50%

  5. Gallery Forest “Mata de Galeria” • Beside to occupy 5% of the biome, has 45% biodiversity; • Relevant role as buffer zone between terrestrial and aquatic systems; • Although protected by law – very threatened by agricultural and urban development

  6. Land cover in the Brazilian Savanna (2002) Natural area Water mass Agricultural area Cultived grassland Urban area Reforestation Land uses in the Cerrado (hectare) Sano et al. 2008

  7. How these land cover changes affect: STUDY AREA • Stream water quality • Flow components: • Bulk deposition; • Runoff; • Soil solution; • Ground water.

  8. STUDY AREAS

  9. Urban cover: 3 streams Natural cover: 3 streams Rural cover: 3 streams • Watersamplingandanalyses: • Samplingevery 15 daysduringwetseasonand 30 daysduringdryseason, alongtwoyears; • Parameters: • pH, electricalconductivity, alkalinity, turbidityanddissolvedoxygen; • Dissolved Organic Carbon (Carbon analyzer); • Ca+2, Mg+2, K+, Na+, PO4-, Cl- and SO4- (Chromatography); • NO3-, NO2- and NH4+(Chromatography) • Total Dissolved Nitrogen (Persulphate digestion). • Filtered samples

  10. RESULTS

  11. Stream water – pH, alkalinity, conductivity and turbidity pH Alcalinity E.C. Turbidity URBAN > RURAL>NATURAL

  12. Stream water - [O2] and [DOC] DO URBAN > NATURAL> RURAL DOCURBAN>RURAL = NATURAL;

  13. Stream water – [TDN], [NH4+], [NO2-] and [NO3-] TDNURBAN>RURAL =NATURAL NH4+ URBAN= RURAL >NATURAL NO2- and NO3- URBAN > RURAL > NATURAL

  14. Stream water - [Ca+2], [Mg+2], [K+] and [Na+] Ca+2 Mg+2 K+ Na+2 URBAN>RURAL >NATURAL

  15. Stream water – [SO4-] and [Cl-] SO4- Cl- URBAN >RURAL >NATURAL

  16. Conclusion A higher nutrient load in streams near to urban and agricultural areas in relation to natural areas

  17. Flow components • Bulk deposition; • Runoff; • Soil solution; • Ground water. • Natural cover • Rural cover • Watersamplingandanalyses: • Samplingevery 15 daysduringwetseason • and 30 daysduringdryseason, alongtwoyears; • Parameters: • pH, electricalconductivity, alkalinity; • DissolvedOrganicCarbon (Carbonanaliser); • Ca+2, Mg+2, K+, Na+, PO4-, Cl-and SO4-, NO3-, NO2-and NH4+(Chromatography) • Total DissolvedNitrogen (Persulphatedigestion).

  18. Experimental design Forest edge Bulk deposition colector Close to the stream (4 to 20 m) Far from the stream (30 to 140 m). Runoff colector Well Lysimeter Stream

  19. [NH4+ ] Flow components Streams

  20. [NO2- ] Streams Flow components

  21. [NO3- ] Flow components Streams

  22. End-Member Mixing Analysis Flow components: Runoff close to stream Soil solution close to stream Groundwater far from stream Groundwater contributed more than 90%

  23. Conclusions • A higher nutrient load in streams near to urban and agricultural areas in relation to natural areas; • Most of the elements did not show changes in flow components • However, land cover change increased N forms concentrations in flow components, specially in the groundwater

More Related