Yucatan Aguas

Environ Monit Assess (2011) 172:493–505 DOI 10.1007/s10661-010-1349-z

Nitrogen and phosphorus budgets for the Yucatán littoral: An approach for groundwater management
Nancy ArandaCirerol · Francisco Comín · Jorge Herrera-Silveira

Received: 18 February 2009 / Accepted: 18 January 2010 / Published online: 17 February 2010 © Springer Science+Business Media B.V. 2010

Abstract Humanactivities have altered the balance of ecosystems to the detriment of natural environments. Eutrophication is a serious risk in Yucatán, a state in the eastern peninsula of México where groundwater supplies the only freshwater to a karst shelf environment. While economic development in Yucatán is increasing, environmental awareness is lagging, and efficient waste treatment systems are lacking. To assesspotential nitrogen and phosphorus inputs into the coastal zone of Yucatán, we analyzed government

reports and the chemical composition of groundwater and aquaculture wastewater. Swine, poultry, and tourism are revealed as the main continental nutrient sources, while groundwater with high nitrate concentrations is the principal coastal nutrient source, a pattern similar to other river dischargesaround the world. This study demonstrates that environmental risk management practices must be implemented in the Yucatán region to protect groundwater quality. Keywords Groundwater · Eutrophication · Nitrogen · Yucatán aquifer · Water management

N. ArandaCirerol Departament de Ecologia, Facultat de Biologia, Universitat de Barcelona, Av. Diagonal 645, 08028, Barcelona, Spain F. Comín InstitutoPirenaico Ecología-CSIC, Av. Montañana 1005, 50192, Zaragoza, Spain N. ArandaCirerol · J. Herrera-Silveira Departamento de Recursos del Mar, CINVESTAV-IPN Mérida, A.P. 73 Cordemex, 97310, Mérida, Yucatán, México Present Address: N. ArandaCirerol (B) Facultad de Química, UNAM Campus Sisal, Universidad Nacional Autónoma de México, Puerto de abrigo S/N, 97356, Sisal, Yucatán, México e-mail:arandacirerol@gmail.com

Introduction Human activities are the main nutrient inputs into coastal ecosystems (Valiela et al. 1992; Vitousek et al. 1997). Nutrient point sources on the coast are easily monitored, but diffuse and atmospheric sources are more difficult to control since they originate in diverse areas subject to climate variability (Carpenter et al. 1998; de Jonge et al. 2002; Spokes andJickells 2005). Soil use for benefits and services (e.g., food and waste disposal) generate the largest human impact on terrestrial ecosystems (Costanza et al. 1997; Vitousek et al. 1997). Nitrogen is important for agriculture (Johnston 1994), but fertilizers may reduce a capacity of ecosystem to provide

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Environ Monit Assess (2011) 172:493–505

benefits to people. Livestock waste canalso increase the nutrient content of surface water and groundwater, leading to cultural eutrophication (Valiela et al. 1992; Tilman et al. 2001, 2002). In temperate regions such as the North Sea, contaminated waters from agricultural fields generate eutrophication and instigate detrimental changes to ecosystems (Jenssen et al. 1994). The Black Sea, which includes the coastal ecosystem as well asriver drainage basins, has similarly experienced changes caused by human impact. For example, the Danube River receives effluents from eight European countries and represents the most significant source of river-borne pollution flowing into the Black Sea (Lancelot et al. 2002). Groundwater contaminated by nitrates from agriculture is a source of nutrients that negatively impacts highly sensitiveenvironmental zones, such as the Great Coral Barrier in Australia (Bell 1991; Thorburn et al. 2003). In the Yucatán peninsula, the only freshwater sources are groundwater springs or seeps on the coast, and aquifers in highly permeable carbonate karst subsoil (Logan et al. 1969; Hanshaw and Back 1980; Back and Lesser 1981; Pope et al. 1991). Since inefficient waste treatment systems were conventional...