Doiran Lake (Macedonian: Доjранско Езеро, Dojransko Ezero; Greek: Λίμνη Δοϊράνη, Límni Dhoïráni), also spelled Dojran Lake is a lake with an area of 43.1 km2 (16.6 sq mi) shared between the Republic of N. Macedonia (27.3 km2, 10.5 sq mi) and Greece (15.8 km2, 6.1 sq mi).
To the west is the city of Nov Dojran (Нов Дојран), to the east the village of Mouries, to the north the mountain Belasica and to the south the Greek town of Doirani. The lake has a rounded shape, a maximum depth of 10 m (33 ft) and a north-to-south length of 8.9 km (5.5 mi) and 7.1 km (4.4 mi) at its widest, making it the third largest lake partially in the Republic of N. Macedonia after Lake Ohrid and Lake Prespa. The lake was on the southern line of the N. Macedonian front during World War I, and its southern shore became the site of the various battles between allied troops and Bulgarian troops in 1916, 1917 and 1918. A monument to one of the battles and two cemeteries for Greek and British troops stand on a hill a few hundred metres south of the lake. Due to the overuse of the lake’s water for agricultural purposes in recent years, Doiran’s water nearly drained out, but the disaster was avoided after the countries took measures to replenish and sustain the lake’s water levels. Frequent and heavy rainfalls, in last years, also helped restoring the lake’s water levels.
The lake is shallow and the bottom lies at an elevation of 138 m a.s.l., while the highest recent absolute altitude above see level of the water surface was 148 m. Before the dramatic water level decrease, the depth of the lake was 10 m, but as low as 4 m lake depth was registered at the beginning of this century (Sotiria and Petkovski, 2004). The lake is of elliptical shape with a maximum length 8.9 km and a maximum width 7.1 km. Forest and semi-natural areas, including agricultural land, cover most of the catchment. The lake is recharged from direct runoff, small rivers and groundwater and it does not have surface outflow2. The lake water surface evaporation is hence the only natural water loss. Main inlets are on the Greek side: Odza Suji (Breska river) with a waterbasin of 94.3 km2, carrying all the waters from the South slopes of the mountain Belasica, and the river Kavakalaris, with the waterbasin of 21 km2. On the Macedonian side, there are 26 smaller rivers, creeks and springs; the most important ones are: Crn Potok, Pazarli Dere, Suva Reka, and Derven Rama.
Dojran basinl is arranged in a dry zone and the lake is a huge water asset for the settlements and horticultural encompassing regions (Griffits et al., 2002). The lake is described as eutrophic (Stankovic, 1931; Smith&Petkovksi, 2001; Popovska et al., 2014), while complete water revive by groundwater and surface inflows and net vanishing in addition to water use bring about shortfall in the mean yearly water balance.
First misuse of the lake water was in 1808 with development of a 1300 m long water system waterway. The main recorded water level in Dojran was 150 m a.s.l. enrolled in 1810 (Stojanov, 2002). Water level motions in the principal half of XX century spurred Macedonian (Yugoslavia) and Greek experts in 1956 to direct water level that should have been kept up somewhere in the range of 144.8 and 147.34 m a.s.l. In the period 1952–1988, the water level was at a normal elevation of 146.45 m a.s.l. (Fig.2). During the period 1983-1987 the water level varied fundamentally over the concurred least level. Because of delayed dry season that began in 1988, just as anthropogenic effects, the water level had been ceaselessly dropping arriving at the base degree of 141.76 m a.s.l.
The anthropogenic exercises were principally associated with water use for agrarian division. In particular, from 1988, as indicated by an understanding between the two nations, Greece began utilizing water from the lake for agrarian water system, through Djol-Ajak channel on the Greek side. For the period 1988-2002 the normal water level diminishing was 34 cm every year. In 2002 the volume of water dropped to about 60×106 m3, showing the water loss of right around 80 % contrasted with the 1956 greatest volume of 280×106 m3. In this period region of the lake diminished from about 41.8 to 29.5 km2 (Bonacci et al., 2015), bringing about the subsidence of the lake’s shore up to 100 m from the fundamental settlements, the vanishing of a great part of the western littoral zone and huge biodiversity misfortune (Ristevski, 1991; Georgievska and Matevska, 1996; Griffiths et al., 2002). This unexpected drop in water level quickened the lake towards a more prominent eutrophic state (Sotiria and Petkovski, 2004). The Hydrological recreation model – precipitation spillover and water equalization model – demonstrated that the principle purpose behind the lessening in water level was utilization of water for water system (EAR/MoEPP, 2007).
From 2003, the water level in the lake has started to increase, mainly due to construction of the Djavoto canal system, but also because of more favourable pluvial regime – significant increase of the annual precipitation sum has been observed in the last decade (Popovska, 2013). The lake depth reached 6.7 m in 2010 and continued to rise in the past five years (see Annex for the satellite photos of the lake in the period 2003-2015).
The hydro system Djavoto includes: two-stage pumping system from the wells in Gjavato near the Vardar River, the outlet basin in Bogdanci village (W = 300m3), a gravity pipeline (L =
19.3 km), another outlet basin near Toplec (W = 300 m3) and an open canal with an outlet to the Lake (L = 0.6 km). The maximum capacity of the system is 1000 l/s. The system has been in use from 2003.
Dojran Lake valley is perhaps the hottest area in this piece of the Balkans (Popovska, 2013). The atmosphere is Sub-Mediterranean and contrasting with the encompassing semi-mainland atmosphere has higher normal least and greatest month to month air temperatures and lower precipitation aggregates. The atmosphere of Dojran locale is likewise affected by the lake water surface and encompassing mountains. The southern piece of the catchment is available to the Thessaloniki Plain and the Aegean Sea, permitting direct impact from the Mediterranean atmosphere. Dissipation from the shallow Dojran Lake is a significant regular determinant of its water balance. Bonnaci and partners (2010, 2015) found a connection between the temperature increment – that had an expanding pattern for the period 1951-2010 (Fig.4) – and the lake’s hydrologic system: when air temperature builds, the water level reductions because of the water misfortune by evapotranspiration and vanishing from the lake water surface. Despite the fact that the period 1989-2002 when the lake water level altogether diminished was additionally described by the exceptional delayed dry season (Myronidis et al., 2012), Bonacci et al. (2015) demonstrated that, in contrast to temperature, yearly precipitation did not assume huge job in the lake water level conduct. Other than being influenced by regular marvels and environmental change, specifically temperature increment, the lake water decline in the late XX century was likewise firmly influenced by exceptional water extraction for water system. The distinction in processed – utilizing water balance hydrological displaying – and recorded water levels show water volume loss of around 200 million m3 which can be connected to water deliberation (Gjesovska, 2013).
The rich biodiversity of Dojran Lake contains Mediterranean, Northern and Eastern botanical and faunal components, yet in addition endemic verdure. Endemic species start from the relict greenery or have determined through the procedure of specialization and adjustment to the particular nearby conditions (Sotiria and Petkovski, 2004).
According to the European Community Habitats Directive 92/43/EEC, Lake Dojran has the following habitats:
1. Oligothropic to mesotrophic standing waters with vegetation of the Littorelletea uniflorae and/or Isoeto-Nanojuncetea type.
2. Natural eutrophic lakes with Magnopotamion (pondweed) or Hydrocharition (free- floating surface communities) type of vegetation. This habitat type is abundant in Dojran with extensive reedbeds with species such as: Phragmites australis (common reed), Scripus lacustris (club-rush), Typha angusifolia (narrow-leaf cattail), Sparagnium erectum (bur-reed). Parts where the lake water withdrew transformed into pastures with commonly found Paspalum distichum (knotgrass).
3. Mediterranean tall humid herb grasslands of the Molinio-Holoschoenion type.
4. Riparian mixed forests of Quercus robur (pedunculate oak), Ulmus Laevis (elm) and Ulmus minor (field elm), Fraxinus excelisior (ash) or Fraxinus anguistifolia (narrow leafed-ash) along the rivers.
5. Salix alba (white willow) and Populus alba (poplar) galleries
On the Greek side a significant natural surroundings is the Mouries Woods on alluvial store.
Forest communities present in the more extensive watershed zone include: Coccifero-Carpinetum orientalis (sub-Mediterranean pseudomaquis made out of bush like evergreen oak – Quercus coccifera and oriental hornbeam – Carpinus orientalis), Quercetum conferatae-cerris (oak and Turkey oak backwoods), Orno-Quercetum petraeae (Sessile oak-hornbeam timberlands), Fagetum (sub)montanum (mountain beech), endemic network Juglando-Platanetum orientalis (pecan plane woods), Carpinetum orientalis-Philyrietosum mediae, Carpinetum orientalis-Quercetum sessiliflorae (timberlands of oriental hornbeam and some oak species, for example, Italian oak – Quercus frainetto).
Commercially most important species in Dojran are fish, including the following species: roach
– Rutilus rutilus, carp – Cyprinus carpio, Vardar chub – Leucaspius delineatus, rudd – Scardinius erythrophtalmus, tench – Tinca tinca, bleak – Alburnus alburnus makedonicus, bitterling – Rhodeus sericeus amarus, Macedonian roach – Pachychilon makedonicus, Gudgeon – Gobio gobio balanicus, Balkan barbel – Barbus peloponnesius, Prussian carp – Carassius gibelio; Vardar spined loach – Cobitis vardarensis, catfish – Silurus glanis, eel – Anguilla Anguilla, perch – Perca fluviatilis, river blenny – Salaria fluviatilis, and the endemic Dojran loach – Sabanejewia aurata doiranica. Three of the above fish species are included in Annex II of Dir. 92/43/EEC (under the species names Barbus plebejus, Sabanjewia aurata and Cobitis taenia), Pachychilon macedonicus and Gobio gobio balcanicus are in the Hellenic Red Data Book and Salaria fluviatilis is included in Annex III of the Bern Convention. Within the ecosystem of the lake Doiran, amphibians consist of ten species (Sidorovska et al. 2001; Dzukic et al. 2001; Sidorovska et al. 2003). Frog species Rana balcanica and newt Triturus karelinii, as well as the subspecies Pelobates syriacus balcanicus, Bombina variegata scabra and Triturus vulgaris graecus, are Balkan endemics. Newt Triturus vulgaris graecus manifests as a neotenic population only in the Dojran Basin, while the Greek marsh frog – Rana balcanica, has its most abundant population within the Lake. The Balkan spadefoot toad – Pelobates syriacus balcanicus, was described from a specimen collected from the shore of Dojran Lake. It should be noted that Tristurus karelinii and Pelobates syriacus (both at the species level) are included in Annex II of Dir. 92/43/EEC and Annex II of the Bern Convention, accordingly.
Other vertebrates include 23 reptile species. The subspecies of European pond turtle – Emys orbicularis hellenica, the subspecies of Kotschy’s gecko – Cyrtodactylus kotschyi skopjensis, the subspecies of European copper skink – Ablepharus kitaibelii stepaneki, and the subspecies of Erhard’s wall lizard – Podarcis erhardii riveti are Balkan endemics. The sand boa – Eryx jaculus turcicus, was first recorded on the Balkan Peninsula at a location within the Dojran Basin. This species is the only European representative of the large family of boas. There is also Emys orbicularis, included in Annex II of Dir. 92/43/EEC, lizards Lacerta viridis and Podarcis taurica included in Annex II of the Bern Convention.
Dojran has 87 bird species (Dangel 1973; Dimovski and Matvejev 1955; Matvejev and Vasic 1973; Micevski 1991). There are about 36 bird species abundant in the area all included in Annex II and III of the Bern Convention. Fifteen of these species are also included in the Birds Directive 79/409/EEC. Dalmatian Pelican Pelecanus crispus and white-headed duck Oxyura leucocephala are threatened species and their presence renders the site as an Important Bird Area for both countries. Other bird species include: great white pelican Pelecanus onocrotalus, purple heron Ardea purpurea, Pygmy cormorant Phalacrocorax pygmeus, wader Recurvirostra avosetta, harrier Circus aeruginosus, shrike Lanius nubicus, among others. There are 53 mammal species in the Dojran basin (Petrov 1992; Krystufek et al. 1992; Krystufek and Petkovski 1999; and Petkovski et al., 2001). Of these, only a few species are directly related to the water biotope of the lake. The most common mammal is the weasel Mustela nivalis, included in Annex III of the Bern Convention. Other terrestrial animals include moths and butterflies (Lepidoptera). Thurner (1964) recorded 103 species from the Family Noctuidae (noctuid moths) within the basin, including the national endemic – Cosmia rhodopsis, and two subtropical species: Scotia spinifera and Mythimna vitellina. Daniel (1964), in his study of the Families Bombycidae (silk moths) and Sphingidae (hawk moths), recognised 56 species in the basin, including the four Dojran endemic subspecies: Zygaena purpuralis doiranica, Zygaena carniolica paeonica, Zygaena ramburi europensis and Cosmotriche potatoria. The Family Geometridae (geometer moths) is represented with 89 species in the Dojran basin (Pinker, 1968). The group Microlepidoptera (small moths) is most numerous in the Dojran basin, comprising 192 species (Klimesch, 1968), including the Dojran endemic species – Cnephasia klimeschi. Finally, Thurner (1964) and Schaider and Jaksic (1989), investigating the butterflies of the Families Hesperiidae, Papilionidae, Pieridae, Lycaenidae and Nymphalidae, recognised 86 species, which is 43% of the diurnal butterfly fauna of N. Macedonia. The total number of recorded species (526) from the Order Lepidoptera shows an enormous diversity within a relatively restricted area. The diurnal butterfly species Lycaena dispar is included in Annexes II and IV of the Habitats Directive 92/43/EEC.
Dojran dragonfly diversity presents 80% the total dragonfly fauna of N. Macedonia. Karaman (1981) recorded 39 species and Peters & Hackethal (1986) added three new species. The dragonfly species Coenagrion ornatum is included in Annexes II of the Habitats Directive. The lake water is also rich in biodiversity and the aquatic fauna includes numerous species. Within molluscs, the aquatic gastropods consist of 21 species, including the Dojran endemic snail – Graecanatolica macedonica (Roding 1966; Sapkarev 1975; Stankovic 1985, 1991), which is considered extinct from 2000. However, some shells of this species were collected in 2009 and 2015 (Fischer et al., 2009; REC, 2015). These are either subfossil shells washed out from sediment, or it is possible that the species may have survived in a small groundwater source and that species is extant (iucnredlist.org, 2013). The molluscs from the class Bivalvia are represented by five species, including Dreissena polymorpha, whose dead shells are present in large masses along the current shoreline zone of the lake. Within segmented worms (Annelid), Branchiobdelidae were occurring as ectobionts of the Balkan river crayfish Astacus astacus balcanicus, with 15 species (Georgevitch, 1955). Four branchiobdelid species have been accepted as Dojran endemics (Petkovski et al., 2003): Branchiobdella capito, Cambarincola dojranensis, Pterodrilus prion, and Xironodrilus crassus. However, the drastic reduction in the populations of river crayfishe within the lake has had a negative effect on the survival of the four Dojran endemic branchiobdelids. Other classes of Annelid include Oligochaeta, represented by 22 species, including the Dojran endemic species – Isochaeta dojranensis, and leeches (Hirudinea), represented by 10 species (Sotiria and Petkovski, 2004).
Arthropods (the phylum Arthropoda), including insects, arachnids, myriapods and crustaceans, is the most numerous taxonomic group within the Animal Kingdom.
Within crustaceans, recent investigations have determined that only nine of the original 25 water fleas (Cladocera) are still present in the lake, restricted to the pelagic complex of the zooplankton (Petkovski et al., 1999, 2001). Copepods, the class Copepoda, used to be represented by all three orders of freshwater copepods: Calanoida, Cyclopoida and Harpacticoida, with a total of 17 species, including the endemic species – Microcyclops varicans dojranensis (Petkovski 1954, 1983, 1991, 1999; Popovska Stankovic 1954, 1990, 2001; Griffiths et al. 2002). However, the more recent analysis indicates that copepods are now represented by only eight species (Petkovski et al., 2001, 2003). Ostracods, the classes Ostracoda, are represented by eight species. Klie (1941) described a new ostracod species from Lake Dojran – Physocypria inversa, which is considered to be Dojran endemic. Petkovski (1958 and 1960) described two new ostracod subspecies from the benthic zone of Lake Dojran – Candona angulata meridionalis and Candona paionica. However, the endemic subspecies Candona paionica was not found in more recent studies (Saprakev et al. 1991; Ryan and Griffiths, 2001). Higher crustaceans used to be abundant in the lake. The Order Amphipoda is represented by three species, and the species Orchestia cavicama and Gammarus roeselii triacanthus used to be abundant in the littoral zone of the lake at the depths of up to 3 m. Still, more recent investigations have shown that they appeared only sporadically (Petkovski et al. 1999, 2001; and Griffiths et al. 2002). The endemic Amphipoda – Niphargus pancici dojranensis – is not directly linked to the lake waters, but found in the spring area of the stream Deribash. Within crayfishes (the Order Decapoda), three species have been recorded in the lake; Atyaephyra desmaresti stankoi was abundant throughout the submersed vegetation of the littoral zone of the lake (reaching an abundance of up to 100 individuals/m2) prior to 1989 and the situation with the other two species is similar. Within insects, stoneflies (the Order Plecoptera) were presented by six species appearing in the streams that flow into Dojran (Ikonomov, 1983, 1986). The species Rhabdiopteryx doiranensis is a Dojran endemic, while Brachyptera macedonica is a national endemic. The subspecies Capnioneura balcanica macedonica, another national endemic, is also described from the same stream near Achikot. Booklice (the Order Psocoptera) is comprised of 16 recognized species (Gunther, 1980). The unique national endemic species of this taxonomic group – Liposcelis macedonicus, is the Lake Dojran endemic, originally described from the vicinity of Achikot. Hadzisce (1953) mentioned the presence of three species of freshwater sponge, including the endemic Dojran sponge Spongilla carteri dojranensis, which has not been recorded in any other freshwater biotope. Living in the shallow littoral zone, which has experienced drastic changes in the late XX and early XXI century, this species has been seriously affected. However, it is estimated that it managed to adapt to the altered circumstances of the lake’s ecosystem
Considering its ecological importance and cultural heritage, Lake Dojran was proclaimed Monument of Nature in 2011 (Official Gazette 51/11). The Monument of Nature covers the lake and its shore, including the riparian zone and reedbeds. According to this law, the territory of the lake on the N. Macedonian side is 27.2 km². The monument of nature Dojran Lake is under the authority of the Dojran municipality. Under this law, the responsible authority is obliged to prepare the management plan and annual programmes containing measures and activities for protection of the site. The Management plan of Dojran Lake, however, should not be limited only to the narrow zone currently under the category Monument of Nature. The management plan should rather refer to the whole Dojran watershed, protecting all the waters that come into the lake (Popovska et al., 2014).
The bilateral cooperation between Greece and N. Macedonia, with regard to the conservation of Dojran Lake, started in 1956 with the agreement that set the maximum and minimum water level of Dojran Lake. The main concern in this period was to maintain the maximum water level for flood protection (Sotiria and Petkovski, 2004). This indicates shift in the environmental threats, from floods to droughts, registered in the second half of XX century. The agreement between Greece and N. Macedonia became ineffective after a consistent decrease of water level. After the ecological catastrophe caused by the water level drop, bilateral meetings took place again at technical and government level at the beginning of this century. The two parts agreed on exchange of information, integrated studies and bilateral efforts towards the establishment of a Joint Water Management Commission. Still, these agreements have not resulted in a fully active cooperation in river basin planning or management of Dojran Lake. Insufficient cooperation and exchange of data and information between N. Macedonia and Greece is hence an obstacle for the Dojran Lake sustainable water resources management (Popovska, 2014). The EU Water Framework Directive could act as an effective instrument for international cooperation as it focuses on watershed scale and also promotes and guides the management of transboundary water bodies among European and non European states (Mylopoulos and Kolokytha, 2008). Regarding the international status of the lake, it is part of the Convention for protection and use of the transboundary watercourses and the international lakes since 1999, although this convention has not yet been ratified by N. Macedonia (Codato, 2015). Dojran is also part of the United Nations Espoo Convention, adopted by the both countries, presenting a framework concerning transboundary cooperation upon which other directives and conventions have been developed. Dojran Lake’s international importance is also connected to its important ecosystem characterized with rich biodiversity, including endemic species3. Dojran presents a “wetland and bio-corridor for numerous animal species, primarily birds” (RENA, 2011). These exceptional natural characteristics included Dojran Lake in: the Catalogue of Wetlands (2002), the National Emerald Network of conservation importance in Europe (2004), the Corine biotope site, the List of Important Plant Areas in N. Macedonia (2004), the Important Bird Area in N. Macedonia according to the criteria of Bird Life International (2010), the Balkan Green Belt (IUCN initiative, 2004) and the World Ramsar List (2007) (RENA, 2011). Dojran Lake is also part of the Inventory of Greek Wetlands as Natural Resources and was included in the Natura 2000 network (RENA, 2011). Furthermore, on the Greek side, the Limni Doirani site is protected under the Birds Directive (SPA) with 35 protected bird species, while the Ydrochares Dasos Mourion site is protected under Habitats Directive (SCI confirmed in 2006) (RENA, 2011).
Bentofauna has undergone dramatic shifts in Dojran Lake as well. Such changes include drastic reductions in the abundance of oligochaetes, from 2,000 to 202 individuals/m2, including Dojran endemic Isochaeta dojranensis (Petkovski et al. 1999; Griffiths et al. 2002), and of Chironomidae larvae, from 2,000 to 200 individuals/m2. An abundance of 25,000 individuals/m² of the endemic snail – Graecanatolica macedonica, was recorded in the lake littoral zone in 1987 by Stankovic. More recent research, however, recorded only 11 individuals/m² (Petkovski et al. 1999; 2001), indicating significant reduction in the presence of this species. The populations of nematodes, on the other hand, have maintained a relatively constant level. The only group that has benefited from the changing status of the lake is the Ostracoda, with an average increase from 100 individuals/m2 to 900 individuals/ m2. This is partly due to the fact that a large number of ostracod taxa is detritus feeder. A reduction in communities of macrophytic vegetation was recorded in littoral zone in the research done at the beginning of the century, including decrease in frequency of some and disappearance of other species. The most significant was the absence of the underwater meadows of Vallisneria spiralis and Ceratophyllum demersum, which used to inhabit the littoral zones of the lake (Matecski&Micevski, 2001; Sotiria&Petkovski, 2004).
Tourism, together with fishery, is the main economic activity in Dojran, although the existing infrastructure is of insufficient capacity for the peak season during summer months (LER, 2006). Communities from ecologically-rich, but economically deprived regions are keen on bringing tourists into the area, seeing it as an income opportunity. However, mass tourism could have negative effect on the environment, in particular the lake water quality and the littoral ecosystem, due to increase in water use and waste water production and, at the same time, new construction sites in the vulnerable beach zone, negatively impacting biodiversity and valuable habitats. Conversely, different alternative approaches to tourism could be less intensive and invasive, while providing benefits for the municipality all year round. Interviewees proposed different approaches to tourism, including ecotourism, health tourism, tourism for elderly, conference tourism, educative tourism and transit tourism.
Dojran local food market
Another aspect that can support local production and attract visitors, including transition tourists, is a local market with both fresh and/or traditional local products. Many local stakeholders expressed desire and need for better developed local food market in Dojran. Besides the local agricultural products – preferably with GAP certificate – the market should also offer local traditional products. This includes delicacy such as green fig jam. Furthermore, olive production has a long tradition in Dojran with an increasing intensity and could present a new brand for this region. Fish market should be part of this new local market in Dojran.