Agricultural terraces and terrace walls are a conspicuous feature of the Mediterranean Forest and agricultural landscapes, which are vital in relation to biodiversity. Aim of the study is to identify the contribution of agricultural terraces and terrace walls in the biodiversity conservation of the forest and agricultural landscapes on Kythira island. Literature review survey indicate that agricultural terraces and terrace walls provide various goods and services, which are vital, and they are potential and interesting resources for the development of this area. It is noteworthy that agricultural terraces and terrace walls are an important habitat for biodiversity. Also, stone terraces and walls create a suitable micro-environment for biodiversity conservation and enhancement. Consequently, these landscape elements should be preserved and exploited as they favor the components of biodiversity which are the source of our food and medicines, fibers, fuels and industrial products. The direct use of the components of biodiversity contribute substantially to the economy and tourism development.
The island of Kythira, also known as Cerigo, is located south of the southeastern tip
of the Peloponnese. The area of Kythira is 277.28 km2 and the length of the coastline
is 114.24 km, while taking into account the 22 islands around it, the total area is 278.65
km2. Its general geomorphologic picture is semi-mountainous, dominated by a low
plateau of 200-300 meters, which is often interrupted by gorges and some valley-like
configurations. This plateau leads to steep cliffs to the west and south, and to the east
and north, to smoother and lower formations, with many beaches. There are several
islands and islets around, with the most important being Dragonares in the east and
Avgo or Hitra in the south
The aim of the present study is to identify the contribution of agricultural terraces and terrace walls in the biodiversity conservation of the forest and agricultural landscapes on Kythira island. 2
The island of Kythira is characterized by the Mediterranean climate with hot and
dry summers and cold winters. Specifically, according to the Climatic Zone
Classification of UNEP (1992), the area belongs to the sub-humid (SH) climate zone
with Aridity Index (AI) values presented to decrease from 0.71 (for the period
19001930) to 0.59 (for the period 1960-1997), indicating that more arid conditions persist
the recent years compared to the beginning of the century
The annual average temperature is 18.0οC, ranging seasonally between 11.6οC in winter and 25.4οC in summer, with intermediate values during the transitional seasons of spring and autumn (15.5οC and 19.6οC, respectively). July and August are the warmest months of the year with average temperatures 26.4°C and 26.2°C respectively, while coldest months are January and February with average temperatures around 11.0°C. The monthly changes of the temperature attributes are presented in Fig. 4, indicating that in the region, generally warm conditions persist during all seasons.
Average Absolute maximum
Maximum Absolute minimum
Minimum 1 2 3 4 5 8 9 10 11
12 6 7
Month
The region’s climate has become significantly hotter the last decades compared to
the past as clearly depicted in Fig. 5. The temperature attributes’ trend analysis was
performed by employing the widely used Mann-Kendall test
Data for the current study were taken from a previously published work and, to safeguard the credibility, only indexed and peer-reviewed articles were used. The following databases were included: Scopus, Google Scholar, PubMed, Science Direct, and MEDLINE.
The island of Kythira is the crossroad of Mediterranean cultures. The fire occurred in 2017 exposed the stone terraces and walls (Fig. 6), works that span hundreds of years, whose maintenance and extension continued until the 1960s, as they are elements of the Greek landscape and its features. According to Koulouri (2004) terraces are, historically, one of the most important and characteristic human interventions in shaping the Mediterranean landscape. They are a very important element of the historical and cultural heritage of the Mediterranean peoples and at the same time of great aesthetic and environmental value.
The idea of the stone terraces and stone walls (Fig. 6) is very likely to have been conceived by the island's inhabitants in ancient times so that they can cultivate the land, mainly due to the steep slope of the soil, and to some extent ensure their survival. Traditionally, the art of tiering has been passed down from generation to generation, among members of each family. Such terrestrial farming has largely been abandoned due to the mechanization of agriculture, intensive farming and the reduction in the share of human labor in agricultural production (Crhysanthaki, 2005).
We should also consider the fact that the systems of stone terraces and walls (Fig. 6) provide a multitude of benefits for both the environment and human societies. They provide Ecosystem Services that are vital, especially on island regions. More specifically, the most important benefits of maintaining stone terraces and walls are: • • • • •
Prevention of soil erosion, both by the action of water and air,
Protection during extreme weather, preventing floods and contributing to the
creation of a local microclimate,
Production, under specific conditions, of high-quality products,
The creation of suitable micro-habitats for the conservation, protection and
enhancement of biodiversity,
Maintenance of the high aesthetic and cultural value of the Mediterranean
landscape
Stone terraces and walls are an integral part of the Mediterranean landscape (Fig.
7). In many cases, they create ecological seals/habitats/nests offering a permanent or
temporary refuge to various biodiversity components, e.g. invertebrates, reptiles, birds,
etc. Indeed, the orientation of the terraces to the south creates a fire hazard, but on the
other hand "retaining walls during the day store solar energy, which is released at night,
thereby creating local microclimate" suitable for many organisms, which in turn leads
to an increase in biodiversity
The micro-environment at the base of stone terraces and walls are characterized by
high humidity and increased primary productivity (dense vegetation), factors which
are important for invertebrate populations (e.g. spiders, phalanx, Carabidae,
Staphylinida, etc.)
As regards the reptiles, their exothermic condition plays a decisive role in the
selection of "good" calorie sites where there is rich food and protection from predators
Stone terraces and walls are also an important habitat for flora diversity and habitat
for dry or shady plants as they find a safe retreat site there, a haven of life. The flora
that grows in these areas hosts species that are scattered by the natural flora of
neighboring areas. Plant species vary greatly from place to place depending on the
micro geographical conditions (microclimate, altitude, etc.)
Stone terraces and walls are part of the island's cultural tradition and heritage and the can contribute to the financial development of the local communities. Under the environmental view, they create suitable micro-environments for biodiversity conservation. It is essential to be preserved as a measure for the protection of the local flora and fauna, for strengthening ecosystems adaptation mechanisms in order to cope with climate change.
Acknowledgment. We thank the Institute of Mediterranean and Forest Ecosystems, Hellenic Agricultural Organization “Demeter” for their bibliographic database.
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