Difference between revisions of "Dynamics, threats and management of dunes"

From Coastal Wiki
Jump to: navigation, search
Line 3: Line 3:
 
==Processes and mechanisms driving natural dynamics & ecosystem development==
 
==Processes and mechanisms driving natural dynamics & ecosystem development==
  
−
During the last thirty years, almost 75% of Mediterranean coastal dunes have been damaged or destroyed, principally by tourism consequences (Géhu, 1985; Salman & Strating, 1992; in Van Der Meulen & Salman, 1993<ref>VAN DER MEULEN F. And SALMAN A.H.P.M., 1993. Gestion des dunes côtières de Méditerranée. ''The first International Conference on the Mediterranean Coastal Environment''. 167‐183.</ref>). There are different kinds of destruction causes. First, the natural vents which are erosion by storms or/and sea level rise, overwash, and sea flooding events. The vulnerability of coastal dunes to flooding depends on the characteristics of the dune system itself: height, width, conservation status etc. It also depends on the intensity and impact of the event (e.g. sea level rise, storm intensity). The taller dunes are more resistant to flooding but possibly more susceptible to erosion while the shorter dunes might be more vulnerable to flooding. In the next century, climate change will lead to a rise of mean sea‐level, a likely increase of storms intensity and frequency and a more contrasted distribution of wetness between winter and summer (GIECC 2001, 2007, in Vinchon et al., 2008<ref>VINCHON C., BALOUIN Y., IDIER D., GARCIN M., MALLET C., 2008. La réponse du trait de côte au changement climatique: Evolution des risqué côtiers en Aquitaine et en Languedoc‐Roussillon dans le siècle à venir. The littoral : challenge, dialogue, action. Lille-France. 11pp.</ref>). These changes will modify the coastal erosion and sea‐flooding hazards. Dune dynamics are driven by naturally occurring disturbances, which can be both common and recurrent. However when these disturbances increase in intensity or frequency or are removed there can be substantial alterations in community dynamics (Martinez and Psuty, 2004<ref>MARTINEZ M.L. and PSUTY N.P., 2004. Coastal Dunes.  Ecology and Conservation. ''Ecological Studies''. '''171''', 386pp. Available from: [http://www.vliz.be/imis/imis.php?module=ref&refid=70677]</ref>). Dunes are thought to be fragile because only a slight disruption (either natural or human induced) may lead to change and long‐term progressive alteration (Carter, 1988<ref>CARTER R.W.G., 1988. Coastal environments. An introduction to the physical, ecological and cultural systems of the coastlines. Academic Press, New York.617pp. </ref>) and their natural diversity might be compromised easily.</br>
+
During the last thirty years, almost 75% of Mediterranean coastal dunes have been damaged or destroyed, principally by tourism consequences (Géhu, 1985; Salman & Strating, 1992; in Van Der Meulen & Salman, 1993<ref>VAN DER MEULEN F. And SALMAN A.H.P.M., 1993. Gestion des dunes côtières de Méditerranée. ''The first International Conference on the Mediterranean Coastal Environment''. 167‐183.</ref>). There are different kinds of destruction causes. First, the natural vents which are erosion by storms or/and sea level rise, overwash, and sea flooding events. The vulnerability of coastal dunes to flooding depends on the characteristics of the dune system itself: height, width, conservation status etc. It also depends on the intensity and impact of the event (e.g. sea level rise, storm intensity). The taller dunes are more resistant to flooding but possibly more susceptible to erosion while the shorter dunes might be more vulnerable to flooding. In the next century, climate change will lead to a rise of mean sea‐level, a likely increase of storms intensity and frequency and a more contrasted distribution of wetness between winter and summer (GIECC 2001, 2007, in Vinchon et al., 2008<ref>VINCHON C., BALOUIN Y., IDIER D., GARCIN M., MALLET C., 2008. La réponse du trait de côte au changement climatique: Evolution des risqué côtiers en Aquitaine et en Languedoc‐Roussillon dans le siècle à venir. The littoral : challenge, dialogue, action. Lille-France. 11pp.</ref>). These changes will modify the coastal erosion and sea‐flooding hazards. Dune dynamics are driven by naturally occurring disturbances, which can be both common and recurrent. However when these disturbances increase in intensity or frequency or are removed there can be substantial alterations in community dynamics (Martinez and Psuty, 2004<ref>MARTINEZ M.L. and PSUTY N.P., 2004. Coastal Dunes.  Ecology and Conservation. ''Ecological Studies''. '''171''', 386pp. Available from: [http://www.vliz.be/imis/imis.php?module=ref&refid=70677]</ref>). Dunes are thought to be fragile because only a slight disruption (either natural or human induced) may lead to change and long‐term progressive alteration (Carter, 1988<ref>CARTER R.W.G., 1988. Coastal environments. An introduction to the physical, ecological and cultural systems of the coastlines. Academic Press, New York.617pp. Available from:[http://www.vliz.be/imis/imis.php?module=ref&refid=11046]</ref>) and their natural diversity might be compromised easily.</br>
  
 
For thousands of years, human activities have been impacting the coastal environment of the Mediterranean Basin through agriculture, husbandry and the deliberate use of fire. In recent decades, tourism has caused important damages on coastal landscapes with the urbanization of the coast, the increase of summer visitors, and the introduction of invasive or exotic species. The most heavily affected habitats are the sandy coastal systems and coastal dunes in particular (Tzatzanis et al., 2003<ref>TZATZANIS M., WRBKA T., SAUBERER N., 2003. Landscape and vegetation responses to human impact in sandy coasts of Western Crete, Greece. J. Nat. Conserv. '''11''', 187‐195.</ref>). The pedestrian and motorized pathways all over dunes lead to vegetation destruction and therefore enhanced weathering and erosion (Moulis and Barbel, 1999<ref>MOULIS D., and BARBEL P., 1999. Restauration des dunes. Réhabilitation et gestion des dunes littorals Méditerranéennes Françaises. Collection: Manuels et Méthodes. BRGM Ed., 75-91.</ref>). Waste deposits and invasive species introduction are also destruction factors. The potential for dune recovery is dependent on the sediment supply in each area and on the intensity of human impact. Dune plants are especially sensitive to disturbance and are heavily affected by humans. Without dune plants, the integrity and preservation of a stable dune complex cannot exist. Anthropogenic impacts combined with the natural regression process of the coastline induce the acceleration of the destruction of the dune vegetation (Araujo et al., 2002<ref>ARAUJO R., HONORADO J., GRANJA H. M., NEVES DE PINTO S., BARRETO CALDA F., 2002. Vegetation complexes of coastal sand dunes as an evaluation instrument of geomorphologic changes in the coastline. Littoral 2002, The changing Coast: 337-339. EUROCOAST/EUCC, Porto-Portugal : 337‐339.</ref>) ultimately leading to to dune destruction.
 
For thousands of years, human activities have been impacting the coastal environment of the Mediterranean Basin through agriculture, husbandry and the deliberate use of fire. In recent decades, tourism has caused important damages on coastal landscapes with the urbanization of the coast, the increase of summer visitors, and the introduction of invasive or exotic species. The most heavily affected habitats are the sandy coastal systems and coastal dunes in particular (Tzatzanis et al., 2003<ref>TZATZANIS M., WRBKA T., SAUBERER N., 2003. Landscape and vegetation responses to human impact in sandy coasts of Western Crete, Greece. J. Nat. Conserv. '''11''', 187‐195.</ref>). The pedestrian and motorized pathways all over dunes lead to vegetation destruction and therefore enhanced weathering and erosion (Moulis and Barbel, 1999<ref>MOULIS D., and BARBEL P., 1999. Restauration des dunes. Réhabilitation et gestion des dunes littorals Méditerranéennes Françaises. Collection: Manuels et Méthodes. BRGM Ed., 75-91.</ref>). Waste deposits and invasive species introduction are also destruction factors. The potential for dune recovery is dependent on the sediment supply in each area and on the intensity of human impact. Dune plants are especially sensitive to disturbance and are heavily affected by humans. Without dune plants, the integrity and preservation of a stable dune complex cannot exist. Anthropogenic impacts combined with the natural regression process of the coastline induce the acceleration of the destruction of the dune vegetation (Araujo et al., 2002<ref>ARAUJO R., HONORADO J., GRANJA H. M., NEVES DE PINTO S., BARRETO CALDA F., 2002. Vegetation complexes of coastal sand dunes as an evaluation instrument of geomorphologic changes in the coastline. Littoral 2002, The changing Coast: 337-339. EUROCOAST/EUCC, Porto-Portugal : 337‐339.</ref>) ultimately leading to to dune destruction.

Revision as of 09:39, 6 July 2012

UNDER CONSTRUCTION

Processes and mechanisms driving natural dynamics & ecosystem development

During the last thirty years, almost 75% of Mediterranean coastal dunes have been damaged or destroyed, principally by tourism consequences (Géhu, 1985; Salman & Strating, 1992; in Van Der Meulen & Salman, 1993[1]). There are different kinds of destruction causes. First, the natural vents which are erosion by storms or/and sea level rise, overwash, and sea flooding events. The vulnerability of coastal dunes to flooding depends on the characteristics of the dune system itself: height, width, conservation status etc. It also depends on the intensity and impact of the event (e.g. sea level rise, storm intensity). The taller dunes are more resistant to flooding but possibly more susceptible to erosion while the shorter dunes might be more vulnerable to flooding. In the next century, climate change will lead to a rise of mean sea‐level, a likely increase of storms intensity and frequency and a more contrasted distribution of wetness between winter and summer (GIECC 2001, 2007, in Vinchon et al., 2008[2]). These changes will modify the coastal erosion and sea‐flooding hazards. Dune dynamics are driven by naturally occurring disturbances, which can be both common and recurrent. However when these disturbances increase in intensity or frequency or are removed there can be substantial alterations in community dynamics (Martinez and Psuty, 2004[3]). Dunes are thought to be fragile because only a slight disruption (either natural or human induced) may lead to change and long‐term progressive alteration (Carter, 1988[4]) and their natural diversity might be compromised easily.

For thousands of years, human activities have been impacting the coastal environment of the Mediterranean Basin through agriculture, husbandry and the deliberate use of fire. In recent decades, tourism has caused important damages on coastal landscapes with the urbanization of the coast, the increase of summer visitors, and the introduction of invasive or exotic species. The most heavily affected habitats are the sandy coastal systems and coastal dunes in particular (Tzatzanis et al., 2003[5]). The pedestrian and motorized pathways all over dunes lead to vegetation destruction and therefore enhanced weathering and erosion (Moulis and Barbel, 1999[6]). Waste deposits and invasive species introduction are also destruction factors. The potential for dune recovery is dependent on the sediment supply in each area and on the intensity of human impact. Dune plants are especially sensitive to disturbance and are heavily affected by humans. Without dune plants, the integrity and preservation of a stable dune complex cannot exist. Anthropogenic impacts combined with the natural regression process of the coastline induce the acceleration of the destruction of the dune vegetation (Araujo et al., 2002[7]) ultimately leading to to dune destruction.

Vulnerability & threats

Key processes to focus on for maintaining ecosystems integrity

Current management practises

References

  1. ↑ VAN DER MEULEN F. And SALMAN A.H.P.M., 1993. Gestion des dunes côtières de Méditerranée. The first International Conference on the Mediterranean Coastal Environment. 167‐183.
  2. ↑ VINCHON C., BALOUIN Y., IDIER D., GARCIN M., MALLET C., 2008. La réponse du trait de côte au changement climatique: Evolution des risqué côtiers en Aquitaine et en Languedoc‐Roussillon dans le siècle à venir. The littoral : challenge, dialogue, action. Lille-France. 11pp.
  3. ↑ MARTINEZ M.L. and PSUTY N.P., 2004. Coastal Dunes. Ecology and Conservation. Ecological Studies. 171, 386pp. Available from: [1]
  4. ↑ CARTER R.W.G., 1988. Coastal environments. An introduction to the physical, ecological and cultural systems of the coastlines. Academic Press, New York.617pp. Available from:[2]
  5. ↑ TZATZANIS M., WRBKA T., SAUBERER N., 2003. Landscape and vegetation responses to human impact in sandy coasts of Western Crete, Greece. J. Nat. Conserv. 11, 187‐195.
  6. ↑ MOULIS D., and BARBEL P., 1999. Restauration des dunes. Réhabilitation et gestion des dunes littorals Méditerranéennes Françaises. Collection: Manuels et Méthodes. BRGM Ed., 75-91.
  7. ↑ ARAUJO R., HONORADO J., GRANJA H. M., NEVES DE PINTO S., BARRETO CALDA F., 2002. Vegetation complexes of coastal sand dunes as an evaluation instrument of geomorphologic changes in the coastline. Littoral 2002, The changing Coast: 337-339. EUROCOAST/EUCC, Porto-Portugal : 337‐339.

Retrieved from "https://www.coastalwiki.org/w/index.php?title=Dynamics,_threats_and_management_of_dunes&oldid=47545"