Green infrastructure is a network of nature, semi-natural areas, and green space delivering essential ecosystem services which underpin human well-being and quality of life (European Commission 2013).
Green Infrastructure is a tool providing ecological, social and economic benefits through natural solutions. It also helps to understand the advantages nature offers to human society and to mobilize investments that sustain and enhance these benefits. The functions of green infrastructures can be environmental (e.g. conserving biodiversity or adapting to climate change), social (e.g. providing green space, improving life quality) and economic (e.g. supporting local economy, providing alternative income sources, boosting tourism and trade).
The role of terraces as green infrastructures
Drystone terraces carved on the hills and mountains have been a major landscape element of the islands of the Aegean and the Mediterranean drystone. These structures allowed for millennia the cultivation of steep and marginal areas with poor and dry soils that diachronically supported local production activities (crop cultivation, livestock farming, beekeeping), thus sustainable land management and human sustenance (Petanidou 2011, 2015).
Focusing on the current situation of the Mediterranean, with the impacts of climate change becoming distinctively notable in the area, the historical existence and utilization of terraces for agriculture may constitute a green infrastructure that is crucial for the island ecosystem well-being and resilience, with multiple benefits towards ecosystem adaptation to climatic change. In essence, cultivation and maintenance of terraced land may have diverse benefits to the environment and nature such as (Petanidou 2015):
1. Re-cultivation with local varieties adapted to local soil and climatic peculiarities to produce high-added value products
2. Reduction of flood risk, following heavy rainfalls and due to landslides
3. Enrichment of ground water potential due to the increased permeability of the soil
4. Avoidance of soil erosion due to the presence of terraces and cultivated crops along the terraces contribute to the containment of soil- resources (mechanically through retention walls, through the planted root systems)
5. Creation of soil, especially in eroded and steep areas, mainly artificially through crushing rock and transferring soil from elsewhere
6. Increase of green surfaces also contributing to the aesthetic, morphological and recreational improvement of rural areas
7. Provision of “oases” of cultivated areas in steep and usually marginal lands which increases ecosystem heterogeneity to the benefit of biodiversity of diverse groups (plants, invertebrates, reptiles, mammals, birds). Cultivated terraces and drystone walls offer a microclimate continuum and constitute refuge for wild animal species, especially during the harsh summer conditions. The base of the drystone walls, characterized by higher humidity vs. the more exposed terrace parts, creates a suitable micro-environment for invertebrates, such as arthropods and molluscs (Pafilis et al 2014, Petanidou 2015). Conditioning temperature is also very important: indeed, since drystone walls maintain moderate thermal relief that is beneficiary for wildlife, particularly during summer months.
In the framework of the LIFE TERRACESCAPE project, re-cultivated large scale expands of terraces are expected to function as green infrastructure, a process to be well-documented, e.g. through environmental & biological indicators. The effort is going to revitalize and modernize primary sector, rending it multifunctional as well as economically and environmentally sustainable by engaging local varieties and climate-friendly cultivation practices, combined with tourism and culture, to sustain a more human local development.
Literature
European Commission (2013). Building a Green Infrastructure for Europe. Luxembourg, 24 pp.
Pafilis P. (2014). Aegean drystone walls: Holding biodiversity (Final report). Programme “scientific projects”. John S. Latsis Public Benefit Foundation. National and Kapodistrian University of Athens, pp.100
Petanidou T. (2011). Terraces – an inseparable element of the island landscape. In: Contemporanean lanscapes of Greece – A geographical approach from above (C. Hadjimihalis, Ed.). Melissa Publications, Athens [In Greek].
Petanidou T. (2015). Terraces of the Aegean – the example of Dodecanese. Parisianou Scientific Publications, Athens, pp. 280. [in Greek].
The project is implemented with the financial support of the European Commission.