Accessibility / Report Error

Land-use effects on river habitat quality and sediment granulometry along a 4th-order tropical river

Efeitos do uso do solo sobre a qualidade de habitat e a granulometria do sedimento ao longo de um rio tropical de 4ª ordem

Abstracts

Land-use change, i.e., the transformation of natural land into agricultural and urban area is among the most important human impacts on habitat quality and species diversity. In this study, we investigated the effects of land use on river habitat quality and sediment granulometry in a larger tropical river, affected by urbanization and agricultural land use. We selected 15 representative sampling reaches in the Rio das Mortes basin, 12 of them along the main river from its headwater to its mouth, and 3 in major tributaries. A habitat survey was conducted in these reaches in the dry season 2010 and sediment samples were taken for granulometry analyses. Sub-basin land cover of reaches was dominated by natural vegetation (41.6 to 60.2% of total land cover), followed by agricultural land cover (38.4% to 56.9%) and urban land cover (1.4% to 5.6%). Sediments were dominated by poorly to moderately sorted silts to sands, little conducive to diverse biological communities. According to the river habitat survey, all investigated river reaches exhibited moderately to totally disturbed habitat integrity, due to diverse and often co-occurring human impacts, such as riparian deforestation, water abstraction, sand and gravel extraction, and margin erosion. Only one of the investigated sampling reaches exhibited the minimum riparian forest corridor width demanded by the Brazilian Forest Code. Our results indicated that river habitat and sediment quality mainly depended on conditions in the direct vicinity of river reaches. Accordingly, initial cost-effective restoration of aquatic habitats could be achieved by relatively simple channel restoration measures and the protection of the riparian corridor in the investigated tropical river.

Neotropical rivers; urbanization; agriculture; structural integrity


Mudanças no uso e ocupação do solo representam um importante impacto antrópico sobre a qualidade de habitats e a diversidade biológica. Os efeitos do uso do solo sobre a qualidade de habitats e a granulometria do sedimento em um rio tropical impactado por urbanização e agricultura fora m investigados. Foram selecionados 15 trechos de amostragem representativos da bacia do Rio das Mortes, sendo 12 localizados no leito principal, desde a cabeceira até a foz, e os restantes em três dos principais tributários. Um levantamento de habitat foi realizado nestes trechos durante a estação seca de 2010 e amostras de sedimento foram coletadas para análise granulométrica. A cobertura da bacia nos trechos estudados foi dominada por vegetação natural (41.6 a 60.2%), seguida por agricultura (38.4 a 56.9%) e urbanização (1.4 a 5.6%). Os sedimentos foram dominados por silte e areia, pouco favoráveis à diversidade biológica. De acordo com o levantamento de habitat, todos os trechos apresentaram integridade moderada ou totalmente perturbada, devido a diversos impactos frequentes, tais como remoção de mata ciliar, captação de água, extração de areia e cascalho e erosão. Apenas um dos trechos estudados apresentou largura de corredor ripário em concordância com o exigido pelo Código Florestal Brasileiro. Os resultados indicam que a integridade de habitat e a qualidade do sedimento riverinos dependem principalmente das condições presentes na vizinhança imediata dos trechos estudados. Assim, a restauração custo-efetiva dos habitats aquáticos poderia ser alcançada por medidas simples de restauração do canal e a proteção da vegetação ripária neste rio tropical.

Rios neotropicais; urbanização; agricultura; integridade estrutural


  • ACUÑA, V.; DÍEZ, J. R.; FLORES, L.; MELEASON, M.; ELOSEGI, A. Does it make economic sense to restore rivers for their ecosystem services? Journal of Applied Ecology, v. 50, n. 4, p. 988-997, 2013. http://dx.doi.org/10.1111/1365-2664.12107
  • ALLAN, J. D. Landscapes and riverscapes: the influence of land use on stream ecosystems. Annual Review of Ecology, Evolution and Systematics, v. 35, n. 1, p. 257-284, 2004. http://dx.doi.org/10.1146/annurev.ecolsys.35.120202.110122
  • AWASTHI, A. K. Skewness as an environmental indicator in the Solani river system, Roorkee (India). Sedimentary Geology, v. 4, n. 1, p. 177-183, 1970. http://dx.doi.org/10.1016/0037-0738(70)90010-2
  • BRAUNS, M.; GÜCKER, B.; WAGNER, C.; GRACIA, X.F.; WALZ, N.; PUSH, M. T. Human lakeshore development alters the structure and trophic basis of littoral food webs. Journal of Applied Ecology, v. 48, n. 4, p. 916-925, 2011. http://dx.doi.org/10.1111/j.1365-2664.2011.02007.x
  • BLOTT, S. J.; PYE, K. GRADISTAT: a grain size distribution and statistics package for the analysis of unconsolidated sediments. Earth Surface Processes and Landforms, v. 26, n. 11, p. 1237-1248, 2001. http://dx.doi.org/10.1002/esp.261
  • CARPENTER, S. R.; CARACO, N. F.; CORRELL, D. L.; HOWARTH, R. W.; SHARPLEY, A. N.; SMITH, V. H. Nonpoint pollution of surface waters with phosphorus and nitrogen. Ecological Applications, v. 8, n. 3, p. 559-568, 1998. http://dx.doi.org/10.1890/1051-0761(1998)008[0559:NPOSWW]2.0.CO;2
  • DUDGEON, D. Tropical stream ecology London: Academic Press, 2008. 316 p.
  • FOLEY, J. A.; DEFRIES, R.; ASNER, G. P.; BARFORD, C.; BONAN, G.; CARPENTER, S. R. et al.. Global consequences of land use. Science, v. 309, n. 5734, p. 570-574, 2005. http://dx.doi.org/10.1126/science.1111772
  • GÜCKER, B.; BOËCHAT, I. G.; GIANI, A. Impacts of agricultural land use on ecosystem structure and whole-stream metabolism of tropical Cerrado streams. Freshwater Biology, v. 54, n. 10, p. 2069-2085, 2009. http://dx.doi.org/10.1111/j.1365-2427.2008.02069.x
  • HUDSON, N. W. Soil conservation Ithaca: Cornell University Press, 1971. 391 p.
  • KALNAY, E.; CAI, M. Impact of urbanization and land-use change on climate. Nature, v. 423, n. 6939, p. 528-531, 2003. http://dx.doi.org/10.1038/nature01675
  • KAMP, U.; BINDER, W.; HÖLZL, K. River habitat monitoring and assessment in Germany. Environmental Monitoring and Assessment, v. 127, n. 1-3, p. 209-226, 2007. http://dx.doi.org/10.1007/s10661-006-9274-x
  • KLINK, C. A.; MACHADO, R. B. Conservation of the Brazilian Cerrado. Conservation Biology, v. 19, n. 3, p. 707-713, 2005. http://dx.doi.org/10.1111/j.1523-1739.2005.00702.x
  • MEIR, P.; COX, P.; GRACE, J. The influence of terrestrial ecosystems on climate. Trends in Ecology and Evolution, v. 21, n. 5, p. 254-260, 2006. http://dx.doi.org/10.1016/j.tree.2006.03.005
  • NASCIMENTO, F. L.; BOËCHAT, I. G.; TEIXEIRA, A. O.; GÜCKER, B. High variability in sediment characteristics of a Neotropical stream impacted by surface mining and gully erosion. Water, Air, and Soil Pollution, v. 223, n. 1, p. 389-398, 2012. http://dx.doi.org/10.1007/s11270-011-0866-x
  • NAZARENO, A. G. Brazil: combat the effects of forest code changes. Nature, v. 486, n. 7402, p. 191, 2012. http://dx.doi.org/10.1038/486191d
  • PEREIRA, H. M.; LEADLEY, P. W.; PROENCA, V.; ALKEMADE, R.; SCHARLEMANN, J. P.; FERNANDEZ-MANJARRES, J. F. et al. Scenarios for global biodiversity in the 21st century. Science, v. 330, n. 6010, p. 1496-1501, 2010. http://dx.doi.org/10.1126/science.1196624
  • PIELKE, R. A.; MARLAND, G.; BETTS, R. A.; CHASE, T. N.; EASTMAN, J. L.; NILES, J. O. et al. The influence of land-use change and landscape dynamics on the climate system: relevance to climate-change policy beyond the radiative effect of greenhouse gases. Philosophical Transactions of the Royal Society A, v. 360, n. 1797, p. 1705-1719, 2002. http://dx.doi.org/10.1098/rsta.2002.1027
  • PIMM, S. L.; RUSSELL, G. J.; GITTLEMAN, J. L.; BROOKS, T. M. The future of biodiversity. Science, v. 269, n. 5222, p. 347-350, 1995. http://dx.doi.org/10.1126/science.269.5222.347
  • SILVA-JUNIOR, E. F.; MOULTON, T. P.; BOËCHAT, I. G.; GÜCKER, B. Leaf decomposition and ecosystem metabolism as functional indicators of land use impacts on tropical streams. Ecological Indicators, v. 36, n. 1, p. 195-204, 2014. http://dx.doi.org/10.1016/j.ecolind.2013.07.027
  • TIESSEN, H.; CUEVAS, E.; CHACON, P. The role of soil organic matter in sustaining soil fertility. Nature, v. 371, n. 6500, p. 783-785, 2002. http://dx.doi.org/10.1038/371783a0
  • VITOUSEK, P. M.; MOONEY, H. A.; LUBCHENCO, J.; MELILLO, J. M. Human domination of Earth's ecosystems. Science, v. 277, n. 5325, p. 494-499, 1997. http://dx.doi.org/10.1126/science.277.5325.494
  • WALSH, C. J.; ROY, A. H.; FEMINELLA, J. W.; COTTINGHAM, P. D.; GROFFMAN, P. M.; MORGAN II, R. P. The urban stream syndrome: current knowledge and the search for a cure. Journal of the North American Benthological Society, v. 24, n. 3, p. 706-723, 2005. http://dx.doi.org/10.1899/04-028.1
  • WANTZEN, K. M. Physical pollution: effects of gully erosion on benthic invertebrates in a tropical clear-water stream. Aquatic Conservation: Marine and Freshwater Ecosystems, v. 16, n. 7, p. 733-749, 2006. http://dx.doi.org/10.1002/aqc.813

Publication Dates

  • Publication in this collection
    22 Jan 2014
  • Date of issue
    Dec 2013

History

  • Received
    28 Oct 2013
  • Accepted
    19 Nov 2013
Instituto de Pesquisas Ambientais em Bacias Hidrográficas Instituto de Pesquisas Ambientais em Bacias Hidrográficas (IPABHi), Estrada Mun. Dr. José Luis Cembranelli, 5000, Taubaté, SP, Brasil, CEP 12081-010 - Taubaté - SP - Brazil
E-mail: ambi.agua@gmail.com