Transcript www.law.ufl.edu

Nutrients in the
Tempisque River Basin,
Costa Rica
Courtney Reijo, Caitlin Pomerance,
Victor Martinez and Andrew Ironside
University of Florida & Universidad de Costa
Rica
Overview
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Land use in the Tempisque River Basin (TRB)
Status of nutrient loading in the TRB
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Potential effects of nutrients on TRB
•
Costa Rica water quality legal framework
•
Florida's water quality legal framework
Introduction to Land Use
• The TRB is located in Guanacaste in
northwest of Costa Rica
•
Tropical Dry Forest in the life zone and the
soils are Vertisol (shallow and stony)
http://www.stthomas.edu/geography/faculty/kelley/physgeog/soils/taxonomy/soil_taxonomy.htm
Tempisque River
• Was the principal way of transportation and
•
trade for the Peninsula de Nicoya.
The principal activities for several decades
were the cattle and the forest harvesting.
http://www.lanorma-ecolodge.com/AnimalesGranja-Guanacaste-s.html
http://revista-amauta.org/2010/12/lo-quepasa-en-isla-calero-tambien-pasa-enguanacaste/
The TRB development
Two principal factors:
1- Panamerican highway
2- PRAT projects from Arenal Dam (Irrigation
Canals)
http://aparthotelgonzalez.com/?p=145
http://hornillas.com/contactenos.html
Typha spp.
• Became in a problem around the 1980's.
•
The probable causes of its rapid expansion
might be:
o
o
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Cattle (removal)
Nutrients (Introduction)
The current method to mitigate it is the
"Fangueo"
Jimenez et al. 2005
Other Stakeholders
Water Quality:
- MINSA
- MINAET
- SENARA
Water Flow Level:
- ICE
Control:
- OTS
- SENARA
Development:
- IDA
- Municipalities
Nutrient Data & Issues
• Is there a nutrient problem?
• What are probable sources if so?
• What are the current gaps in WQ
information?
Downstream Protection for:
Lower reaches of Tempisque River
Palo Verde National Park
Gulf of Nicoya
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Palo Verde
• Little data in regards to nutrient impacts
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Nutrients should be considered along with
hydrology
o
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Without nutrient limitation, plant growth unlimited
2009 study in PV noted that species
richness increased with decrease in
nutrients in soil and water
Tempisque River Data
• Little data available
....actually 2 papers
•
Synthesis of current info:
o Newbold, 1995 - forest sites
 nutrient concentrations in streams
related to local runoff
 streams are P-limited
Tempisque River Data
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Little data available
•
Synthesis of current info:
add graph
% Agriculture within watershed
Hagamen, 2008
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Gulf of Nicoya: Issues
and Data
Unique
characteristics
Two sources of
nutrients:
o
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3 Rivers
Equatorial
Subsurface
Waters (ESW)
Relative proportion
Kress et al., 2002
Gulf of Nicoya: Unique
Characteristics
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Hydrography makes upper Gulf more
susceptible to algal blooms
Adapted from Wolff, M., Chavarria, J.B., Koch, V., and J.A. Vargas. 1998. A trophic flow model of the Golfo de Nicoya, Costa Rica.
Summary of Gulf Issue
• 1983 - 2006 studies conducted
• Back and forth debate
•
Conclusions:
o
NO3, NO2, and NH4 greater at mouths of rivers
o
Concentrations correlate to runoff/rainy season
o
ESW primary source but more likely in lower Gulf
Potential Sources and Issues
• Is there a problem?
•
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Likely - future issue?
What are probable sources if so?
o NPSP from crops and plantations
o Industry, wastewater?
What are the current gaps in WQ
information?
o Influence of various land uses upstream
and downstream
o NPSP estimates
o
Costa Rica Water Quality Legal
Framework
Hierarchy
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Constitution
International Treaties
National Law
Executive Directives
Reglamentos
Water Quality Law
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• Ley General de Agua Potable
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Ley General de Salud
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Ley Organica del Ambiente
Ministerio de Ambiente, Energia, y
Telecomunicaciones (MINAET)
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Guiding Principles of National Water
Management
Criteria and methodology for evaluation of
superficial water sources
Physiochemical and microbiological
parameters for wastewater
MINAET, cont'd
• Regulates water reuse
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Defines different water uses
System of payments for contaminated
substances
Comision de Implementacion y Desarrollo
en la Cuenca Arenal Tempisque (CIDECAT)
Subcommittee on Water Quality
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Ministerio de Salud Publica (MINSA)
Instituto Costarricense de Acueductos y
Alcantarillados (AyA)
Instituto Costarricense de Electridad (ICE)
CIDECAT, cont'd
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• Area de Conservacion Arenal Tempisque Sistema Nacional de Área de Conservación
(ACAT-SINAC)
Other Members
MINAET, Servicio Nacional de Aguas
Subterraneas, Riego y Avenamientos
(SENARA), OTS
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Why Florida - Land Use
Trends
"The Southern Florida Coastal Plain." USGS.
(Above) "Cuenca de los rios Tempisque y
Bebedero." OET. (Left)
Why Florida - Correlating
Impacts
"The fish disappear when the
red [tide] moves in...People
who swim in red tide may
experience rashes, skin
discomfort..." Tico Times.
(2012).
Florida's TMDL Process
• Classify waterbodies
• Assign standards
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o
narrative & numeric
Extensive monitoring by DEP and WMDs
o
report to EPA every 2 years
If waterbody does not meet standard, then
TMDL is developed
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"the maximum amount of a pollutant that a
waterbody can receive and still meet the water
quality standards as established by the 1972 CWA"
Best Management Practices (BMPs)
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Best Management Action Plan
(BMAP)
o Stakeholders allocate
allowable nutrient loads
Nonpoint source polluters:
o BMPs
UF Institute of Food and
Agricultural Services (IFAS)
o Regionally & Activity
Specific BMPs
o Everglades Agricultural Area
(EAA)
Best Management Practices (BMPs)
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leveling cropfields
collecting aquatic veg
berms & sumps
precision fertilizer and
water application
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Stormwater Treatment Areas (STAs)
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like a Band-aid
taxpayer dollars
Recommendations