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Folded, young mountains of medium elevation, stretching in an arc about 1,500 km long (with a chord of almost 500 km) from the city of Bratislava in the northwest to the
Iron Gate on the Danube River in the southeast and covering an area of about 200,000 sq km, the Carpathians are part of the Alpine mountain system and border on the old Czech,
Polish, and Ukrainian massifs and Dobrudja, being separated from them by a band of young depressions - along the Morava River and Vistula River, the Sian Lowland and
Dniester Lowland, the Subcarpathian Depression, and the Wallachian Depression. The
Pannonian Basin, which cuts north into the mountains along the Tysa River and Bodrog
River and their tributaries, occupies the central part of the arc.
The Carpathian Mountains consist of three geologically distinct bands: the outer flysch, the central crystalline, and the inner volcanic. Only the flysch band is continuous, connecting the Carpathians into one whole. The crystalline band is interrupted in the middle for a distance of over 200 km. Thus, the Carpathians are divided into three parts: the Western Carpathians and the Southern Carpathians, both of which consist of three bands, and the Eastern Carpathians, which are only 100-120 km in width and consist only of the flysch and volcanic bands. http://www.mantleplumes.org/Carpathians.html
Figure 1: The Carpathian Mountains
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The diagram below explains part of the genesys of the Romanian Carpathians.
Figure 2: a. Tectonic blocks (ALCAPA and Tisza-Dacia) whose convergence and continental collision with the European Plate resulted in the formation of the Carpathian arc during Tertiary times (after Csontos, 1995); b. Location of the study area in the southern Eastern
Carpathians (simplified after Girbacea & Frisch, 1998)
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Romania’s landscape is dominated by the Carpathian Mountains, a mountain system that cuts through the country in a circular arc and covers about one-third of
Romania’s total area. Neamt district is located in the north-eastern part of the country, enclosing some of what can be considered to be the southern end of the Eastern
Carpathians, the Ceahlau and Bistritei Mountains. Three rivers cross Neamt: Bistrita,
Siret and Moldova. There are three major attractions in the Neamt district:
1) The lake of accumulation Izvorul Muntelui was created in 1960. It skirts the valley of Bistrita.
2) Gorge of Bicaz , making the connection between Transilvania, to the west, and Moldova, to the east, it is one of the most impressive natural
3) monument of Romania.
The Lacu Rosu (lake red) is a natural dam, unique for Romania, formed in
1837 by the flow of a great part of the north-eastern slope of the Ucigas mount. The area which surrounds the lake was declared natural reservation faunistic and floristic.
Figure 3: Map of Neamt
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Figure 4: Lake Lacu Rosu
Lacul Rosu (Ghilcos) is natural storage lake at 980 m altitude, near Bicaz Gorges.
The lake has "L" form, is 10 m deep (maximum depth is 10.5 m), an area of 12.7 ha, and a 2830 m circumference. The lake is formed recently, in the summer of 1837. Then, after some abundant rains, a great quantity of rocks and debris slided from the Northen side of the Killer Rock (Stanca Ucigasului), blocking the Bicajel river.
The water have accumulated and formed a natural storage lake. The unusual magic is amplified by a lot of empty truncks of the old fir trees, which come out from the water passing through the image of Little Suhard reflected in the lake mirror.
The name Lacu Rosu - Red Lake comes from the reddish alluvia deposited in the lake by its main tributary. The lake is unfortunately in danger because of the great quantity of alluvia transported by the tributary rivers (Rosu, Licas, Oii, Huhard and
Ghilcos (Killer)).
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Figure 5: Bicaz Gorges
Bicaz Gorges, gorges in the Eastern
Carpathians, on the river Bicaz, making the connection between Transylvania and
Moldavia, is 8 m long (from Lacu Rosu resort till Bicazul Ardelean village). The gorges attract by its beauty many tourists every year. They are crossed by a winding road.
At only 3 km from the Lacu Rosu resort, offers beautiful views. The limestone walls of the gorges are like a medieval fortress walls. One can admire the "Altar Stone" - rocky mountain 1120 high, impressive by its verticality, important for the alpine climbing; "Piatra Pintestilor" (847 m) and
"Piatra Arsitei" (835 m) peaks.
Figure 6: Bicaz, the dam and the storage lake
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The storage lake Izvorul Muntelui, also known as Lake Bicaz is the greatest artificial lake (antropic) that has been accumulated on an internal river in Romania.
Placed on the upper course of Bistrita, the lake has formed as a result of the construction of the Bicaz Dam. Its purpouse was intended to be the alimentation of the hydroelectric power plant Bicaz-Stejaru, which has 6 generators. At its maximum filling level it has a length of 31 km.
Throughout the hydrographic bazin of the lake (4035 km
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) the average height of the landscape is 1100m. The maximum height difference encountered is about 1800m
(between Inau Peak 2280m and the bottom of the lake 425m). This determines a climatic leveling effect with important repercursions on the hydrologic regim of the lake.
Air temperature ranges between 16.5 – 17.5 o
C during summer and -4 – -5 o
C during winter time, the annual average beeing 6.5 – 7 o
C. Differences in air temperature are closely related to the lake’s climatic rithm. The maximum in amount of heat stored within the m
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of water is reached during the month of October, inertial heat placing the maximum air temperature in the month of August and not July as expected.
Regarding water transparency, the lake can be placed in a tranzit category between an eutrophic and oligotrophic lake, with values ranging from 2m to 10m. Luminosity within the lake decreases as depth increases. Experiments conducted revealed important differences between the surface and the lake’s depths, aspect that explains creation of different ecosystems. At depths over 35-40m there exists an aphotic zone with specific life developing there.
Analyzing the ecologic succesion Bistrita river – Lake Izovorul Muntelui – Bicaz the physico-chemical factors were found to be crucial in influencing habitat changes and ecosystems.
The maximum amount of oxygen found within the lake occurs during the month of
March and has the value of 11mg/L for depths of 0-30m. At depths of 40m and below, the maximum is reached two months later. The minimum values range between 6-8 mg/L.
The dynamics of the pH of the lake consists of specific fluctuations depending on the seazon and on depth. Thus ample fluctuations are observed at the surface of the lake, throughout the surface, were values range between 7.4 and 8.3. These values indicate a weak alkaline reaction for the lake.
The seazonal variation of the average concentration of nitrates underlines the existance of two caracteristic periods. In the cold seazon, the nitrates concentration is higher, decreasing with approximately 1mg NO
3
/L in the warm seazon. The maximum values for nitrates concentration range from 2-3 mg/L and the minimum from 0.5-2.0 mg/L.
The total phosphorus concetration was determined to decrease in time, from values of about 0,040 mg/L to 0.050mg/L between years 1999-2000. There are no observations regarding different distributions on the horizontal and vertical direction.
Overall, the physico-chemical analysis of the lake’s regim concludes in the following observations. The existance of a stabilized thermical regim resulting in a specific stratification, high levels of oxygenation, low levels of organic materials dissolved and also the weakly alkaline reaction of the lake includes it in the oligotrophic lakes, with a slow transition to a mezotrophic lake.
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The concetrations of organic material are better summarized in the table below:
Interval
Section
Organic
Substance
Organic
Carbon
Organic
Nytrogen
(cm) (g %) (g %) (mg % g)
0 - 5
5 - 10
10 - 15
15 - 20
B a r r a j j
3,58
3,39
5,71
5,09
2,08
1,97
3,31
2,95
259,71
399,53
403,10
304,37
Average
0 - 5
5 - 10
10 - 15
15 - 20
S e c u
4,44
3,75
3,58
3,29
3,97
2,58
2,18
2,08
1,98
2,30
341,67
349,82
137,01
287,93
404,72
Average 3,65 2,12 294,87
0 - 5
5 - 10
10 - 15
15 - 20
Average
0 - 5
H a n g u
C a l l u g a r r e n i i
4,20
3,75
3,36
4,90
4,05
4,98
2,44
2,18
1,95
2,84
2,35
2,89
267,27
273,08
241,63
544,72
331,67
338,60
5 - 10
10 - 15
7,93
3,64
4,60
2,11
315,15
298,17
15 - 20 3,58 2,08 280,08
Average 5,03 2,92 308
The fitoplancton developed in the lake has a very important contribution to the ecosystem formed, because of the large biomass that can be formed be algae cells and the ecofiziological interactions with the medium. Fitoplancton is the most important producer of organic substance in the lake’s biotop. In the first 15 years in the lake’s existance of collecting samples, the following species were identified: Cyanophyta, Euglenophyta,
Pyrrophyta, Cryptophyta, Chrysophyta, Bacillariophyta, Chlorophyta, Conjugatophyta.
From the composition of the fitoplancton, the dominance of diatomees in number of species and in population density, rezults that the level of trophia of the lake is relatively low, especially in the early stage after its formation. Consequent apparition of
Chrysophyta and Chlorophyta led to the diversification of fitoplancton composition.
Masive development of the Oscillatoria rubescens population indicates for the period
1971-1974 an acceleration of the eutrophization process.
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The zooplancton is also a very important link in the food chain of the biotop developed around and within the storage lake Izvorul Muntelui. The three major categories of zooplancton are:
Protozoarele
: in lake Izvoru Muntelui’s water there was a single tipe determined, Tintinnopsis.
Rotiferele : reprezent approximatively 32% of the total number of zooplanctonic taxons.
Cladocerele : the group reprezented by the biggest number of sistematical units, summing up to 44% of the total number of taxons.
Research is conducted with the aim of quantitatively estimate how much zooplancton is produced and how productive it is. Experiments show that production is significantly affected by local conditions, big differences beeing recorded throughout different sections of the lake.
The important role that the zooplancton plays in the circuit of matter and energy within the ecosystem created can be underlined also by the ample trophical relations that this functional group has with the higher order consumers, fish.
Some zooplancton species are known to have bioindicator properties, their existance providing clues about the quality of water. Also in the storage lake Izvorul
Muntelui the existance of Brachionus calyciflorus, Lecane lunaris, Chydorus sphaericus,
Diaphanosoma brachyurum, Paracyclops fimbriatus are such bioindicator species. Their regional specific spread and high quantitative fluctuations show an interference of specific zones within the lake.
The conditions in the storage lake allow also for growth of a various range of bacterioplancton . The development of bacteria populations is closely related to the concentration of organic substances produced in the lake, to the way the fitoplancton decomposes chemicaly and to the physico-chemical factors.
The contribution of microorganisms to the biogenous circuit of nytrogen is essential, especially in the decomposition and mineralization state of mitrogenous organic substances. The fiziological groups of bacteria responsible for these biochmical transformations show ecological particularities determined by the limnological features of the ecosystem.
The amonification process is not constant throughout the length of the lake, as it is influenced by various factors. Quantitative values range from 10,000 cells/mL to 22,000 cells/mL . The populations of amonificator bacteria are much denser at the surface, above
20m depth. In autum, due to the increase in nutritive substances, the amonification process reaches its peak.
The ihtiofauna (fish species) of the lake Izvorul Muntelui is different of that of the
Bistrita river, due to its special conditions. Fish is more abundant in the lake than in the river, species that dominate beeing: mreana reprezenta 44 %, scobarul 26 %, iar cleanul
20 % (names are given in romanian).
The storage lake Izvorul Muntelui – Bicaz has been, from its formation up to today, a place were evolution of specific mountain lake ecosystems and biotops allowed researchers to obtain important results that led to theoretical breakthroughs in the field.
The economical importance of the lake, together with the turistical attraction it poses make the lake an important asset. To prevent polution problems, the guvernment declare
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the region natural reservation and placed it under protection. The hydrocentral that uses the potential energy stored by the lake is one of the most important power supplys in
Romania. http://www.neamt.ro/Imagini/Izv_Muntelui/Baraj_01.htm
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http://www.neamt.ro/Imagini/Izv_Muntelui/Baraj_02.htm
http://www.ici.ro/romania/en/turism/c_est.html
1. "MSN Encarta - World Atlas." http://encarta.msn.com/map_701516076/Romania.html
(03/12/05
23:12:17)
2. "MSN Encarta - World Atlas." http://encarta.msn.com/map_701516076/Romania.html
(03/12/05
23:15:26)
3. "MSN Encarta - Romania." http://encarta.msn.com/encyclopedia_761559516/Romania.html
(03/12/05 23:38:59)
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4. "MSN Encarta - Romania." http://encarta.msn.com/encyclopedia_761559516/Romania.html
(03/12/05 23:39:31)
5. "MSN Encarta - Romania." http://encarta.msn.com/encyclopedia_761559516/Romania.html
(03/12/05 23:40:07) http://www.neamt.ro/Date_gen/Bicaz/Lac_Izv_Muntelui.html
http://www.mantleplumes.org/Carpathians.html
http://globetrotteuse.canalblog.com/archives/2004/10/20/ http://www.ici.ro/romania/en/turism/c_est.html
http://www.encyclopediaofukraine.com/pages/C/A/CarpathianMountains.htm
http://www.referat.ro/referate/geografie/pagina1.htm
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