Prioritizing the conservation of coastal dunes in Northern Spain FELPETE, J. I. & FERNÁNDEZ IGLESIAS, E.

Transcription

1 Prioritizing the conservation of coastal dunes in Northern Spain FELPETE, J. I. & FERNÁNDEZ IGLESIAS, E.

2 2 Dunes in the Atlantic Biogeographic Region: some controversial questions ( to discuss) 1. The Atlantic Biogeograhical Process is fine but, what about the differences within this Biogeographical Region? 2. Does it make sense to prioritize the conservation of dunes in northern Spain? (most of you know how they are) 3.Are we conserving something with a few value (in N Spain)? Sites of Conservation Importance (SCI) or Sites with Restoration Needs (SRN)?

3 3 TALK OVERVIEW 1.Life+ARCOS (overview) 2.Caracterization of cantabrian dunes (european context) 3. Understanding the origin of sediments 4. Facing the loss of biodiversity 5.How to prioritisize

4 4 Project Life+ARCOS actions (overview) PARTNERS (6) SITES (10) Duration: (2019) Coordinating: University of Oviedo (INDUROT) Partners typology: Universities, Regional authorities, National authorities responsable for management of the coasts, Private sector

5 5 Project Life+ARCOS actions (overview) Elimination of pine trees Elimination of AIS Improve sand acumulation (sand traps) Physical protection (fencing) Plantation of structural plants Plantation of non structural species 10 sites included in Natura 2000

6 6 Some characteristics of Cantabrian coast and dunes 1.Coastal landscape is dominated by large to small cliffs 2.Dunes are small (on this occassion size matters!) 3.Dunes are not abundant (really scarce) 4. Small river basins for dune nourishment (Cantabrian range is quite close to the sea) 5. Coast is settled on diverse lithologies 6. Dunes include an important number of protected species

7 7 Erosional (rocky) vs Depositional (sedimentary) coasts Littoral of Northern Spain is characterized by an erosional and rocky coast (red line), where cliffs are dominant. Yellow lines represent depositional coasts. See the differences!!

8 8 Zoom in to Spain and the Cantabrian coast In Basque Country, Cantabria and the Asturian Regions only about 292 hectares are still occupied by dune habitats 2110, 2120 and 2130*; meaning about 16% of the dune habitats occurring in the Atlantic Bioregion in Spain. The remaining 84% of the Atlantic Spanish dunes are located in the Galician Region. Even in Northern Spain differences in dune habitats occurrence are significant 84 % 16% AtlanticBiorregion in Spain

9 9 Regional setup: small river basins The rivers in the Northern slope of the Cantabrian range drop by 2600 m in as much 70 km horizontal to its base level in the Bay of Biscay. This fact gives rise to high gradient river channels with an important contribution of coarse bedload transport in their sediment transfer dynamics. Cantabrian Sea Cantabrian range Rainfall average

10 10 85 Fluvial systems 85 small river basins ends in the Cantabrian sea 99% of the Cantabrian dunes are located in these river mouths But nol all river mouths have dunes

11 11 Lithology also matters! Region of Asturias Three main lithologies are present. 1. Siliciclastic 2. Mixed 3. Calcareous Western coast Siliciclastic lithologis Valdés Ribadesella Llanes Central coast Mixed lithologies Easter coast Calcareous lithologies

12 12 Origin of sediments: rivers RIVERS. Rivers are an essential source of sediments towards the coast. Largest coastal sites where sand is acumulated occur in the East acumulaciones arenosas en el litoral cantábrico aparecen al E de las desembocaduras fluviales. Mesotidal (<4 m)

13 13 Case study: Barayo (W cantabrian coast) EVOLUTION Since 1956 to present

14 14 Historical review of dune dynamics (Barayo) 1956 to 2006 Dune s front moves forward about 30 m 2006 to 2014 Dune s front moves backward about 30 m

15 15 Erosion rates: Barayo (W cantabrian coast) Region of Asturias: target site Barayo In 2014 essential embryonic and white dunes were destroyed by destructive storm surges 2006 Pine trees 2014 Embryonic White

16 16 Trend analysis of storm surges

17 17 The loss of dunes is not homogeneous

18 18 Managing pine trees, a common issue BARAYO LIENCRES Galician Asturias Cantabria Basque Country

19 19 Almost any dune species was found! 115 m Loss of dune habitats DOES IT MAKE SENSE TO TALK ABOUT CONSERVATION? MAYBE, IT SHOULD BE BETTER TO TALK ABOUT RESTORATION

20 20 Facing the protection of dune species PROTECTED IN ALL THE ADMINISTRATIVE REGIONS Glaucium flavum Otanthus maritimus Medicago marina Chamaesyce peplis Halting against the loss of biodiversity also means fighting against the loss of genetic diversity PROTECTED IN ONE OR MORE ADMINISTRATIVE REGIONS

21 21 Dune loss could lead to regional extinction SEED COLLECTION EX SITU CONSERVATION PLANT PRODUCTION REINTRODUCTION

22 22 Prioritisation needs information 1. In 2003 a cartographic and thematic database was developed by INDUROT fluvial systems were characterized (estuarines and dunes) 3. Objective: give support to decision makers (prioritize)

23 23 Cartography Base map Aereal image Habitats / Environmental Units

24 24 Database Geological / Geomorphological Images Land use Vegetation / plants occurrence Animals

25 25 Rating the interest for conservation 38% of dunes and 48% of estuaries were destroyed by human impacts: landfill and buidings hectares are still occupied by dunes

26 26 Assesing the importance of human impacts Absence < 0 Compatible 1-3 Moderate 3-5 Severe 5-7 Cirticial 7-10 Serantes Esteiro Barayo Guadamía La Huelga Poo Penarronda Porcía Frexulfe Esva San Pedro Artedo Ñora Merón Niembro Purón Cobijero Tapia Sta Mª Mar Verdicio Bañugues Perán España La Griega Espasa La Vega Cuevas del Mar San Antolín La Franca Navia Nalón Villaviciosa Ribadesella Tina Mayor Viavélez Luarca Avilés Aboño Piles Llanes

27 27 Main conclussions 1. There are important differences in the way we have to manage the dunes in the Cantabrian area. Actions over the small river basins could be included to improve the sediments feeding. 2. The Atlantic dunes have to cope with the same problems but the working scales are so different that the solutions should be different, and also te priorization. 3.Same impacts on the cantabrian dunes could result in the loss the entire dune system with strong consequences on the biodiversity.

28 28 Aknowlegments Life+ARCOS staff T.E. Díaz A. Bueno C. Ley J. Varas J.I. Felpete L. Oreja L. García E. Iglesias J.L. Tejerina J. Marquínez THANKS FOR YOUR ATTENTION!!