Threats and Impacts to Groundwater-Dependent Wetlands Doñana, Spain

(1)

Spain

Threats and Impacts to Groundwater-Dependent Wetlands Doñana, Spain

Marisol Manzano and Emilio Custodio

¹

Statement

Key Conclusions & Recommendations

• Natural flow is disturbed by intensive and localized groundwater exploitation due to pumping, leading to serious environmental impacts.

• Groundwater is the main contributor to many environmental, economical and social goods and services in Doñana.

Main caracteristics:

• Great diversity of biotopes such as lagoons, marshlands, fixed and mobile dunes, scrub woodland and pine forest.

• Habitat to over 875 plant and 365 bird species and home to several threatened species.

Aquifer / Country Setting & Characteristics

Main patterns of groundwater-dependent wetlands in Doñana

Aquifer vulnerability

Status evolution of the location:

• 1969:Creation of Doñana National Park

• 1981:Biosphere reserve (UNESCO-MAB)

• 1982:RAMSAR Site ( Humid Zone of International Importance)

• 1994:Natural World Heritage Site

Fig/Tbl-USE

Undisturbed situation

• Regional piezometry disturbed by intense pumping (October 1996)

Fig/Tbl Key2

Threats and impacts Lessons Learned Planned Implementing Actions

Main features of natural flow in an undisturbed situation

1. Phreatic level close to soil surface most of year.

2. Groundwater discharges through wetlands.

3. Wetlands are abundant and mostly permanent.

4. Riparian areas: buffer zones attenuate NO3 in discharging polluted groundwater.

Fig/Tbl Key2

Main features of disturbed flow from pumping

1.Depletion of phreatic and piezometric levels, causing:

• riparian / phreatophyte vegetation to disappear

• springs, diffuse dischargeand small ravines may disappear

• enhanced erosion and sediment transport

• wetlands inundation frequency and lasting decrease

2. Wetland surface decrease 3.Pollutants (nutrients) more persistent,

spreading deeper and wider

Groundwater pumping

• Groundwater discharge to depressions and Creeks during the dry season of the year.

• Seasonal / interannual stream generation

Fig-Schema/Tbl-Management

• Groundwater discharge to depressions and creeks during the dry season of the year.

• Seasonal / interannual groundwater discharge.

Fig-Schema/Tbl-Governance

1Dept. Geotechnical Engineering, Technical University of Catalonia, UPC Campus, Barcelona, Spain

• Groundwater is the main contributor to many environmental, economical and social goods & services in Doñana.

• Intensive groundwater abstraction during 35 years modified many wetland's natural hydrological pattern:

1.Pumping (concentrated in aquifer discharge areas) converted permanent wetlands into temporal or sporadic, and many sporadic ones disappeared.

2.Many small ravines converted from lineal phreatic discharge zones into irrigation excess collectors; they are jeopardised by nutrients and pesticides.

Restoration of wetlands natural performance requires to restore the aquifer hydraulic

balance:

-Decreasingabstracted volumes and re-locationof wells.

Wetland Patterns Groundwater Exploitation Threats and Impacts

•

Doñana aquifer supports hundreds of wetlands with different geomorphic and hydrological pattern.

Most wetlands are directly related to groundwater.

• Uncontrolled deforestation for 40-50 years favoured sand mobilisation and relocation.

• Eucalyptus (introduced 50 years ago) induced a local increase of the evapotranspiration causing impacts of lowering water table.

DISCLAIMER: Poster draft prepared by IWRM.org on behalf of the author(s). Any inconsistencies between author(s) input materials and the poster is unintentional.

Location: Doñana aquifer, SW Spain, between Sevilla, Huelva and Cádiz.

PLIO-QUATERNARY ≈Doñana aquifer Marsh Unit: clay Eolian Unit: sand Guadiamar river terraces

Deltaic Unit: sand and silt Alluvial Unit: sand and gravel

Lagoon Town River

UTM (km)

SEVILLA 4140

4100

710 750

HUELVA

marshes RIVER La Rocina

TINTO RIVER

Erased El Rocío dunes

Active dun es Aquifer extent:

aprox. 3600 km²

Doñana National Park: 54251 ha Peripheral buffer zone: 26540 ha Doñana Natural Park: 55377 ha Total protected surface: 136168 ha CÁDIZ

Lagoon Town River

UTM (km)

SEVILLA 4140

4100

710 750

HUELVA

TINTO RIVER

aprox. 3600 km²

Doñana National Park: 54251 ha Peripheral buffer zone: 26540 ha Doñana Natural Park: 55377 ha Total protected surface: 136168 ha PLIO-QUATERNARY ≈Doñana aquifer

Marsh Unit: clay Eolian Unit: sand Guadiamar river terraces

Lagoon Town River

UTM (km)

SEVILLA 4140

4100

710 750

HUELVA

TINTO RIVER

aprox. 3600 km²

Doñana National Park: 54251 ha Peripheral buffer zone: 26540 ha Doñana Natural Park: 55377 ha Total protected surface: 136168 ha PLIO-QUATERNARY ≈Doñana aquifer

Marsh Unit: clay Eolian Unit: sand Guadiamar river terraces

Lagoon Town River

Deltaic Unit: sand and silt Alluvial Unit: sand and gravel Lagoon

Lagoon TownTown RiverRiver

UTM (km)

SEVILLA 4140

4100

710 750

HUELVA

TINTO RIVER

aprox. 3600 km² UTM (km)

SEVILLA 4140

4100

710 750

HUELVA

TINTO RIVER

aprox. 3600 km²

Doñana National Park: 54251 ha Peripheral buffer zone: 26540 ha Doñana Natural Park: 55377 ha Total protected surface: 136168 ha

Doñana National Park: 54251 ha Peripheral buffer zone: 26540 ha Doñana National Park: 54251 ha Peripheral buffer zone: 26540 ha Doñana Natural Park: 55377 ha Doñana Natural Park: 55377 ha Total protected surface: 136168 ha CÁDIZ

CÁDIZ 2b. Main environmental aspects

AUGUST 1985

2b. Main environmental aspects

AUGUST 1985 AUGUST 1985

La Rocina ravine

Dry spring or ravine

Groundwater pumping Groundwater

pumping

La Rocina ravine

pumping

La Rocina ravine

pumping

La Rocina ravine

pumping