**1. Introduction**

40 Soil Erosion Studies

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Forests perform multiple and interrelated social, economic and environmental functions and can be comprised among the ecosystems with the greatest biodiversity. The contribution of forests is multiple and renewable and, therefore, they constitute a most valuable natural resource.

The benefits / values of forests can be divided into those of direct and indirect use. The first category includes the value of timber, which is used, on one hand, in shipbuilding and, on the other hand, in supporting a great chain of industries such as construction, furniture manufacture, printing and packaging. The forestry sector provides about 8% of the total manufacture added value. Forest feedstock, goods and services can also provide important background for the economic reinforcement and green development in the countryside. The primary wood industry offers sawn wood, fibreboard, particleboard, pulpwood, fuelwood as well as wood chips and bark for bioenergy, in fact it employs more than 2 million people and it often involves small or medium enterprises in rural areas (Confederation of European Forest Owners).

Apart from wood, which constitutes the main forest product, forest ecosystems provide a range of products of economic value such as bark, resin, honey, small berries, aromatic leaves (laurel), mushrooms, medicinal herbs, game, forage material etc. The value of forest biodiversity can not be ignored. Forests serve not only as shelter of flora and fauna, but also as a valuable natural gene pool. The value of information deriving from forest biodiversity for pharmaceutical use is subject to ongoing scientific research.

Recreational, aesthetic and health effects of forests can also be placed among their economic and socio-cultural values of immediate use. Forests, with their great surface, are the only part of every country that is free from pollution sources, while forest light, with its low intensity and high content in green radiation, has a soothing effect on the nervous system. For these reasons, forest-tourism, a specific form of tourism, is being developed which can be combined with walking tourism and ecotourism, and is a constantly developing category of mild and environmentally friendly tourism. Forests that are being managed for recreational purposes raise the value of neighbouring properties (Pearce 2001) and encourage tourism. Moreover, employment, particularly for populations who live near the forests and the exploitation of forest energy sources to produce soft forms of energy (biomass) can be added to the long list of benefits from forests.

Deforestation / Reforestation in Mediterranean Europe: The Case of Greece 43

Overall, 13 million Ha of forest land per year were being attributed to other uses or destroyed by natural causes during the decade 2000-2010, while during the decade 1990- 2000, the corresponding forest land was 16 million Ha / year. On the other hand, the creation of new forests, protection programs of the landscape and natural expansion of forests reduce this loss. For instance, the net modification in forest land for the years 2000-05

In the Caribbean, Europe, North America and Oceania, most countries do not present significant changes in their forest lands, whereas, in Africa and South America, the majority

During the decade 2000-2010, the six countries that presented the highest rates of forest land loss were Nigeria, Zimbabwe, Myanmar, Indonesia, Brazil and Venezuela. Correspondingly, the six countries that produced the largest growth rates of their forest land were Viet-nam, China, Turkey, Italy, Norway, Spain and India. The increase of forest land in these countries can be attributed mainly to the afforestation programs (China has proceeded to a large-scale afforestation) and to the natural expansion of forests. Agriculture is considered to be the main cause of afforestation. In the logic of "slush and burn" agriculture, farmers cut down and burn trees in order to produce farm lands or stockbreeding lands (FAO, 2005). Forest insects and diseases are a major threat to the forests of the world, particularly in temperate and northern forests (e.g. beetle Dendroctonus *ponderoseae*, wiped out more than 11 million hectares in Canada and the western United States of America since late 1990), however, they affect less than 2% of forests at a global level (FAO, 2010). Finally, fires affect not only forest cover and the subsequent reduction of carbon accumulation, the protection from soil erosion and, generally, the reduction of all functions and services of the forest, but they also release into the atmosphere large quantities of greenhouse gases. Naturally, certain types of forest ecosystems are adapted to natural fire (eg in Mediterranean ecosystems), but, very often, a fire can get out of control, or torrential rains may follow immediately after the fire leading to soil erosion and simultaneous loss of seeds (eg of the Mediterranean Pinus *halepensis*). Globally, forests affected by fire contribute for 1% of the total annually, taking into consideration that several countries,

Therefore, overall, global carbon capture is decreasing as a result to a forest land loss

The first systematic effort to record Greek forests was made by the Forest Service via the "First National Forest Inventory" that started in 1963 and ended in 1992. The inventory data cover important quantitative aspects of forests, allocated geographically by county, catchment basin and forestry. However, qualitative data, on one hand concerning the trees

Therefore, according to this first national inventory of Greek forests, land uses in Greece,

**Land uses % of the total expanse of the country**

and on the other hand the entire forest ecosystem, are not adequately covered.

Forests 19.0 Forestlands – Pastures 43.3 Agricultural crops 30.0 Settlements, arid areas, rocks 5.6 Lakes, rivers, marshes 2.1 Table 1. Land uses according to the first inventory of Greek forests

was -7.3 billion Ha / year. (FAO, 2005)

of countries are presenting significant losses in forest land.

particularly in Africa, do not record forest lands hit by fires.

**3. Current state of forests in Greece** 

were as shown in Table 1.

tendency.

The hydrologic function of forests, including protection against soil erosion, prevention of flooding while protecting settlements and infrastructure, a significant reduction in flood peaks, enrichment of underground aquifers and a contribution to the quality of water from an chemical and microbiological point of view, can be placed among the benefits and indirect use values of environmental character of forests.

The forest also has many environmental functions: it provides wind protection, protection from noise, and has an impact on climatic factors (light intensity and quality, mitigation of extreme summer and winter temperatures, air humidity).

Special attention should be paid to the key contribution of forests to the oxygen cycle, to absorption carbon dioxide and to air de-pollution (with physio-mechanical and biochemical means), also taking into account the context of climate change. According to the Global Organisation of Food and Agriculture, the world's forests store more than 650 billion tons of carbon (44% in their biomass, 11% in dead wood and litter and 45% in forest soil). Whereas, according to data from Eurostat (2009), at least 9.580 million tons of carbon have been stored in biomass in the forests of the EU of 27, without taking into account the amount absorbed by the dead biomass or forest soils.

Forests along with the oceans comprise the main mechanisms that regulate the balance the equilibrium of the CO2 cycle. A hectare of forest of average productivity processes, each year, 10-12 million cubic meters of air to retain at least four tons of CO2. Thus, it contributes significantly to maintaining / improving atmosphere quality both as a CO2 consumer, as much as an O2 producer. Concern for increased CO2 and its implications on climate change is plausible, however, a truly significant problem, arises from the fact that the largest feedback mechanisms for regulating CO2, such as forests and oceans, are losing their regulatory capacity due to deforestation (2/3 of forests worldwide have already been destroyed) and marine pollution.

The above mentioned complex values of forests demonstrate the imperative need to protect and preserve them.

#### **2. Condition of forests globally and in Europe**

At a global level, forests cover 30.3% of the total surface of the earth, meaning that 0.62 Ha of forest correspond to each inhabitant of the earth. More than half of the forested areas belong to the Federal Government of Russia (Russian Federation), Brazil, USA, Canada and China (FAO, 2005).

Regarding the European Union, forests cover an area of 177 million hectares or 42% of its total area. The countries with the largest forest coverage are Finland (77%) and Sweden (75%), followed by Spain (57%), Italy (37%), Germany (32%) and France (31%). The countries with the smallest forest coverage are Malta (1%), Ireland (10%), Holland (11%) and the United Kingdom (12%). In the territory of the united Europe about 4% of the world's forests are located, but, average forest land corresponding to each European resident is small (0.36 Ha), due to increased population density. However, forest land per capita varies from 4.4 Ha (Finland) to 0.07 Ha (Belgium) (Eurostat, 2010).

Between the years 2000 and 2005, forest coverage in the EU increased by 1.6%, a fact that can be attributed not to a cease of pressure on forests, but mainly to the abandonment and consequential afforestation of agricultural land and to the abandonment of mountain summer pastures.

While, at global level, deforestation has decreased, however, the conversion of tropical forests to agricultural land, in some countries, continues and at an alarming pace too.

The hydrologic function of forests, including protection against soil erosion, prevention of flooding while protecting settlements and infrastructure, a significant reduction in flood peaks, enrichment of underground aquifers and a contribution to the quality of water from an chemical and microbiological point of view, can be placed among the benefits and

The forest also has many environmental functions: it provides wind protection, protection from noise, and has an impact on climatic factors (light intensity and quality, mitigation of

Special attention should be paid to the key contribution of forests to the oxygen cycle, to absorption carbon dioxide and to air de-pollution (with physio-mechanical and biochemical means), also taking into account the context of climate change. According to the Global Organisation of Food and Agriculture, the world's forests store more than 650 billion tons of carbon (44% in their biomass, 11% in dead wood and litter and 45% in forest soil). Whereas, according to data from Eurostat (2009), at least 9.580 million tons of carbon have been stored in biomass in the forests of the EU of 27, without taking into account the amount absorbed

Forests along with the oceans comprise the main mechanisms that regulate the balance the equilibrium of the CO2 cycle. A hectare of forest of average productivity processes, each year, 10-12 million cubic meters of air to retain at least four tons of CO2. Thus, it contributes significantly to maintaining / improving atmosphere quality both as a CO2 consumer, as much as an O2 producer. Concern for increased CO2 and its implications on climate change is plausible, however, a truly significant problem, arises from the fact that the largest feedback mechanisms for regulating CO2, such as forests and oceans, are losing their regulatory capacity due to deforestation (2/3 of forests worldwide have already been

The above mentioned complex values of forests demonstrate the imperative need to protect

At a global level, forests cover 30.3% of the total surface of the earth, meaning that 0.62 Ha of forest correspond to each inhabitant of the earth. More than half of the forested areas belong to the Federal Government of Russia (Russian Federation), Brazil, USA, Canada and China

Regarding the European Union, forests cover an area of 177 million hectares or 42% of its total area. The countries with the largest forest coverage are Finland (77%) and Sweden (75%), followed by Spain (57%), Italy (37%), Germany (32%) and France (31%). The countries with the smallest forest coverage are Malta (1%), Ireland (10%), Holland (11%) and the United Kingdom (12%). In the territory of the united Europe about 4% of the world's forests are located, but, average forest land corresponding to each European resident is small (0.36 Ha), due to increased population density. However, forest land per capita varies from 4.4

Between the years 2000 and 2005, forest coverage in the EU increased by 1.6%, a fact that can be attributed not to a cease of pressure on forests, but mainly to the abandonment and consequential afforestation of agricultural land and to the abandonment of mountain

While, at global level, deforestation has decreased, however, the conversion of tropical forests to agricultural land, in some countries, continues and at an alarming pace too.

indirect use values of environmental character of forests.

extreme summer and winter temperatures, air humidity).

by the dead biomass or forest soils.

destroyed) and marine pollution.

**2. Condition of forests globally and in Europe** 

Ha (Finland) to 0.07 Ha (Belgium) (Eurostat, 2010).

and preserve them.

(FAO, 2005).

summer pastures.

Overall, 13 million Ha of forest land per year were being attributed to other uses or destroyed by natural causes during the decade 2000-2010, while during the decade 1990- 2000, the corresponding forest land was 16 million Ha / year. On the other hand, the creation of new forests, protection programs of the landscape and natural expansion of forests reduce this loss. For instance, the net modification in forest land for the years 2000-05 was -7.3 billion Ha / year. (FAO, 2005)

In the Caribbean, Europe, North America and Oceania, most countries do not present significant changes in their forest lands, whereas, in Africa and South America, the majority of countries are presenting significant losses in forest land.

During the decade 2000-2010, the six countries that presented the highest rates of forest land loss were Nigeria, Zimbabwe, Myanmar, Indonesia, Brazil and Venezuela. Correspondingly, the six countries that produced the largest growth rates of their forest land were Viet-nam, China, Turkey, Italy, Norway, Spain and India. The increase of forest land in these countries can be attributed mainly to the afforestation programs (China has proceeded to a large-scale afforestation) and to the natural expansion of forests. Agriculture is considered to be the main cause of afforestation. In the logic of "slush and burn" agriculture, farmers cut down and burn trees in order to produce farm lands or stockbreeding lands (FAO, 2005). Forest insects and diseases are a major threat to the forests of the world, particularly in temperate and northern forests (e.g. beetle Dendroctonus *ponderoseae*, wiped out more than 11 million hectares in Canada and the western United States of America since late 1990), however, they affect less than 2% of forests at a global level (FAO, 2010). Finally, fires affect not only forest cover and the subsequent reduction of carbon accumulation, the protection from soil erosion and, generally, the reduction of all functions and services of the forest, but they also release into the atmosphere large quantities of greenhouse gases. Naturally, certain types of forest ecosystems are adapted to natural fire (eg in Mediterranean ecosystems), but, very often, a fire can get out of control, or torrential rains may follow immediately after the fire leading to soil erosion and simultaneous loss of seeds (eg of the Mediterranean Pinus *halepensis*). Globally, forests affected by fire contribute for 1% of the total annually, taking into consideration that several countries, particularly in Africa, do not record forest lands hit by fires.

Therefore, overall, global carbon capture is decreasing as a result to a forest land loss tendency.
