Rila Monastery Nature Park Management Plan - part - usaid

February 2004
The above-cited findings show that, as a whole, the waters within the territory of Rila
Monastery Nature Park are clean. There are no major sources of pollution with
biological or chemical waste in the two major rivers’ combined drainage area.
Biological pollution from the sewage collectors of populated places is insignificant
owing to the very small amount of sewage waters discharged.
2.3.6 Hydrobiology
There are, thus far, no comprehensive studies that establish the current all-round
hydrological status of the territory of Rila Monastery Nature Park. The data presented
below were collected prior to 1997 and apply mostly to some groups of invertebrates
encountered in Ribni, Smradlivoto and Suhoto Lakes. The following data exist
regarding the groups of invertebrates and their spread in the lakes of the area:
• The testaceous amoebas group, represented in RMNP by 35 to 40 separate
species, or 70% of all species encountered in the lakes of Rila Mountain;
• The plankton rotatoria and crustaceans group – 15 to 20 species, 15-16% of all
encountered in the lakes of Rila Mountain;
• The ephemeroptera and plecoptera group – 14 species, 58% of all encountered in
the lakes of Rila Mountain;
• The leeches group – 2 out of 3 groups encountered in Rila Mountain.
Of the invertebrate fauna inhabiting the rivers and brooks there are scientific data
solely about the simulidae group, represented in the Rilska River by 28 species, 71%
of all species of that family encountered in the lakes and rivers of Rila Mountain.
2.4 Soils and soil formation processes
2.4.1 Soils
Pursuant to the Comprehensive Soil, Climate and Vegetation Zoning Plan of the
Republic of Bulgaria, RMNP falls in the medium and high-altitude zone of Rila subregion
of the Thracian forest vegetation region.
There are some complex soil formation processes taking place in the territory of the
Park, determined by the complex impact of a variety of abiotic and biotic factors,
subordinated to an altitudinal (vertical) zoning pattern. All types of soils encountered
in the Park are of the metamorphous class of Cambisols. Depending on the altitude,
all three types of that soil class are represented in RMNP: brown forest soils,
mountain-forest dark soils and mountain-grassland soils. The medium forest
vegetation zone comprises the lowest reaches of the Park (ca 800m asl) and extends
upwards to some 2,000 m. The dominant soils in that zone are brown forest soils and
mountain-forest dark soils, with the latter spreading still higher, towards the dwarfpine
sub-zone and the sub-alpine pastures. The high-mountain forest-vegetation zone
comprises the highest parts of the mountain, at altitudes over 2,000m asl, and is
dominated by mountain-grassland soils, which cover the alpine pasture zone.
Rila Monastery Nature Park
Management Plan -Draft
2004 - 2013
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