Wetlands, territory and risks:Wetlands, territory and risks: a geographical approach a geographical approach to risk analysis to risk analysis in the Po Delta (Italy)in the Po Delta (Italy)

2006 - SRA Conference, LjubljanaConference topic: Social contexts and responses to risk

Sara ARIANOUniversità degli Studi di Padova, Université Paris Sorbonne - Paris IV sara.ariano@unipd.it

Summary

• A geography of risk

• Wetlands functions; Man and wetlands

• Case study: Po Delta - Veneto (Italy)

– The study

– First results: main risks, societies, perceptions

– Some conclusions: risks and territory

A geography of risk

GEOGRAPHY provides theoretical and technical instruments for the analysis of territorial processes.

e.g.: theories of territorialisation, geography of complexity; spatial analysis, GIS

RISK:

• is linked to specific territorial features

• influences the construction and evolution of territory

• is inscribed in environment, has specific spatial features

• is also a matter of scale

MAN ENVIRONMENT

TERRITORY :environment modified by human action, during several phases of territorialisation

(Raffestin, Turco, …)

What is “wetland”?

"Wetlands are areas of marsh, fen, peatland or water, whether natural or artificial, permanent or temporary, with water that is static or flowing, fresh, brackish or salt, including areas of marine water the depth of which at low tide does not exceed six metres" (Article 1.1). In addition Ramsar sites "may incorporate riparian and coastal zones adjacent to the wetlands, and islands or bodies of marine water deeper than six metres at low tide lying within the wetlands" (Article 2.1).

(Ramsar convention, 1971)

RISK MANAGEMENT

Economical

Ecological

Social Cultural

Technical

WETLANDS:

FUNCTIONS and VALUES

Wetlands functions and risk mitigation

• HYDROLOGICAL FUNCTIONS:

flooding risk mitigation

wetlands act as retention basins

water storage

wetlands can assure water supply and maintain surface water flow in periods of droughts

• BIOCHEMICAL FUNCTIONS :

improving water quality= phytodepuration

retention or transformation of some polluting substances and nutrients (from the use of chemical fertilizer); filtration process is especially due to abundant wetland vegetation

Man and wetlandsFor a long time wetlands have been undervalued and despised as unhealthy and unproductive spaces

Recent “passion”for wetlands:

the opinion on wetlands has changed amongst scientists and society in general.

Wetlands conservation as a primary issue for biodiversity and sustainable development

But sometimes wetlands are still considered as wastelands…

Case Study: Po Delta – Veneto (Italy)

Between two administrative regions: Veneto and Emilia-Romagna

A Regional Park, since 1997

Protected area = 12.592 ha

The study (work in progress…)

PhD work (thesis defense: 2007-8) on Po river Delta

FIRST PROJECT OF WORK:

• Objectives:Evaluating the integration of wetlands in risk management plans

Comparing people’s perceptions of wetlands and risk with management plans

• Methodology:Collecting bibliography, documents, plans and laws

Fieldwork study: interviews, schedules collecting and elaborating data

Comparing management plans and people’s perception

•Hypothesis:

- People’s perception:

Undervaluation of functions of wetlands, especially about risk prevention

Undervaluation of risks

- Risk management plans: towards an integration of wetlands

A suspended river

Po river embankment: normal flood level is higher than ground level

Villages are often next to the embankment;

increasing vulnerability

In Po Delta, ground level is under sea-level (average: –2 / -3 m)

In order to keep reclaimed lands dry, water-scooping machines have to be used continuously

Subsidence, mainly due to extraction of methane until the Sixties

Drainage and subsidence

The evident crisis: droughts

3 severe droughts in the last 4 years: 2003, 2005, 2006

25 july 2006: the lowest hydrometric level for Po river water flow = 180 m3/s;

(measured at Pontelagoscuro station)

Salt water intrusion, up to 20 km from coast line

Evident effects in the Delta: – agriculture: rice cultures destroyed, corn and

horticulture damaged – no potable water for 15.000 inhabitants

Photo: La nuova ecologia, august 11th, 2006

Superposition of land uses

housesagricolture

tourism

Sacche (clams, mussels)

Valli da pesca

aquaculture

energy

Photo: The thermoelectric power plant of Polesine Camerini

New projects for the Delta

New industrial zone at Cà Cappello (Porto Viro)

Termo-electrical power plant of Polesine-Camerini (Porto Tolle): conversion to “white” coal

Gas terminal and regasification plant (Porto Levante)

Natural park

or energy park?

Management Plans (PAI Delta)

Autorita' di Bacino del fiume Po,

Progetto di Piano stralcio per l'Assetto Idrogeologico del Delta (PAI-Delta), 2001.

Tab. 5: Levels of danger

First results• Identification of main risks:

- Flooding risk - Droughts - Pollutions

•Management Plans:Based on simple calculations of flood level Delta separated from the rest of catchment area

• Wetlands’ integration in Risk Management: extremely marginal

Fieldwork study, interviews to main local actors: institutions, economy, population

• No risk at all! (maybe just droughts…)

• Thanks to technology: we trust on new embankments

• Wetlands?

Risks and reactions

Risk level is beyond comprehension and rationality of inhabitants “we cannot manage risk, so let’s ignore it”

Looking for economic development acceptable level of risk is increased

Crisis: looking for the guilty water management in catchment area:“there could be enough water, but upstream regions are favoured”

Wetlands as laboratories of risk

Risk as an element of a territorial system: it results from the relationship between man and the environment, in a specific territorial context.

Wetlands as “laboratory” to analyse the territorial dimension of risk:

• dynamic, quickly changing environment

• concentration of fluxes and relationships of actors

• wetlands role in risk prevention linked to the choices of human societies, according to people’s perception

• wetland properties in risk prevention:

eliminating wetlands increasing vulnerability

Po Delta is a complex territory, resulting from the interaction of human societies (both local and foreign) and a changing environment

“Natural hazard” or “territorial risk” ?

Technical representations of natural hazard, based on calculations of flood level, cannot completely explain a complex risky territorial context:

vulnerability is increased by human behavior, linked to cultural, social and historical factors

Awareness of territorial peculiarities as a pre-condition for the creation of a culture of risk

Bonifica

(reclaimed lands)trust in human ability to control

and “organize” nature

Thanks for your attention

Sara ARIANO

sara.ariano@unipd.it Co-tutored PhD :

Università degli Studi di Padova, Dipartimento di Geografia

“G.Morandini”

Université Paris Sorbonne - Paris IVUMR “Espaces, Nature et Culture”