Detailed Assessment

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7.2. Detailed Assessment

Assessment of the influence of the Hot Spots on biodiversity and its natural habitat was carried out using 14 indices, which were grouped into 5 divisions:

- general

- fish

- water birds

- near-bottom organisms

- plants.

For each Hot Spot, an individual table was prepared for each index. Additionally, summary tables for each Hot Spot representing all of the indices characterized are also provided.

7.2.1. General information

7.2.1.1. Proximity of Hot Spots to Wildlife Sanctuaries

There is only one wildlife sanctuary in the basin of the Dnipro River, that is, the Berezinsky Biosphere Reserve. However its distance from the nearest Hot Spots considerably exceeds that specified by the criteria of the methodology (Annex D, Table D1); it is probable that none of the selected Hot Spots have a significant adverse effect on the biodiversity of Berezinsky biosphere reserve.  Thereupon the value of index assigned in Annex D, Table D1 is qualified as 0 for all the Hot Sots.

7.2.1.2. Proximity of Hot Spots to the National Parks

The situation with the national parks is similar to situation with wildlife sanctuaries (Annex D, Table D2).  There is only one National park in the Dnipro River basin – Pripiatsky, established on the basis of former Pripiatsky landscape-hydrological reserve. Its remoteness from the nearest Hot Spots exceeds 15 km and therefore it is not expected that the Hot Spots have and an adverse impact on this national park.

7.2.1.3. Proximity of Hot Spots to the Territories Frequented by Rare and Endangered Species

In the Dnipro River basin most of the Hot Spots have a significant influence upon the habitat of rare and endangered species (Annex D, Table D3).  Habitats of numerous rare and endangered aquatic and periaquatic species are located in the zone of influence of industrial and communal enterprises of the largest population centres.

In the assessment of the impact of Hot Spots upon biodiversity it is necessary to take into consideration that nearby significant population centres usually have several point sources of pollution which affect biodiversity simultaneously.  It is practically impossible to reveal the impact of only one Hot Spot both due to the migration of fish and birds from one source of pollution to another and the insufficiency of observational data.

Habitats of rare and endangered species that are affected by the large towns with developed industrial sectors include:

- Retchitsa: sterlet, fish-hawk, small sea gull and ordinary halcyon.

- Gomel:  sterlet, big bittern, black stork, ordinary halcyon, fidgety cane, herring gull, hooping swan and Dnipro groundsel.

- Mogilev: sterlet, sandpiper–magpie and water chestnut.

- Bereza: fidgety cane and big bittern.

- Bobruisk: sterlet, barbel, black stork, ordinary halcyon, hooping swan and white water lily.

- Borisov: brook trout, sterlet and ordinary halcyon.

- Orsha: barbel, small gull and silvery gull.

- Mozyr: sterlet, big merganser, bluebill, black loom, lake tortoise, grey crane and black stork.

- Zhlobin: small gull, black stork, silvery gull, ordinary halcyon and water chestnut.

- Pinsk: dabchick, black loom, big merganser, big bittern, big egret, squacco, grey crane and black stork.

- Svetlogorsk: water chestnut.

With respect to Minsk, there are no known rare and endangered species recorded in the Red Book of the Republic of Belarus within a 15 km distance from the Hot Spot (Minsk vodokanal).  However, this does not mean that an adverse impact on biodiversity has not been occurring.  Quite the contrary, the impact of Minsk City on biodiversity is so great that their habitat has been destroyed and they are no longer present in the vicinity of the city and its wastewater treatment plant.  Therefore, in Annex D, Table D-3 the expert qualified the impact of Minsk City and Minsk vodokanal as 5 points.

7.2.1.4. Proximity of Relatively Unprotected Areas of Ecological Significance to the Hot Spots

Most of the Hot Spots in question are located in the vicinity of ecologically significant, but unprotected areas.  This category includes territories with a great deal of species biodiversity.  Annex D, Table D-4 presents the information regarding the proximity of Hot Spots to such areas.  In some cases Hot Spots are located in the immediate proximity to reserves, e.g. Svetlogorsk heat station.

Nearly all industrial towns discharge industrial effluent in the immediate proximity to such ecologically significant areas.  At the same time there are Hot Spots, which discharge effluent to territories which separated from ecologically significant areas by arable land (e.g. Slutsk vodokanal).

7.2.1.5. Proximity of Hot Spots to Ecologically Sensitive Areas

Ecologically sensitive areas include flood plains along with former riverbeds, lakes, bushes and meadows as well as adjacent lakes, callows and forests.  The proximity of Hot Spots to ecologically sensitive areas is presented in Annex D, Table D-5.  As shown in the table practically all the Hot Spots and most of the industrially developed cities are located nearby such zones and have the potential to have an adverse effect on these areas.

Proximity of Hot Spots to ecologically sensitive areas is not the only indicator of importance.  Studies, monitoring and concrete data of negative impacts of the Hot Spots on these zones are of primary importance.  Unfortunately studies identifying direct negative impacts of Hot Spots on ecologically sensitive areas are rare.  Potential useful data includes the following: 

- Reduction of quantity and size of young fish;

- Mass fish kills;

- Presence of heavy metals in plants and animals as well as in sediments and the soil of floodplains;

- Change in habitats (i.e., excessive vegetative growth: reeds in ponds and lakes; woody vegetation (bushes and saplings) in meadows).

Such direct data was not available for most Hot Spots, however, considering the number of contaminants and the associated chemical composition emitted from the Hot Spots, it is possible to assume with a high probability that they have had adverse impacts on ecologically sensitive areas (by analogy with those Hot Spots where such data are available).

In many cases the focus should not on the negative impact of Hot Spots on habitat, but on the Hot Spot contributing to changes to habitat.  It should be noted that numerous species are not suppressed or suffering negative impacts due to the altered conditions, and some species may prosper.  Some examples include many aquatic plants which often grow more intensively downstream of a Hot Spot compared with upstream.  Effluent from Hot Spots may be beneficial, not harmful, providing nutritive materials that foster plant growth.  For example, effluent discharges from wastewater treatment facilities of the cities of Mogilev and Zhlobin have not had a negative effect on the water chestnut (Red Book of the Republic of Belarus) as this plant grows and propagates downstream these cities without being inhibited. 

Taking into account the aforementioned information, Annex D, Table D-6 presents the expert evaluation of the impact of Hot Spots (and towns) on ecologically sensitive areas.  The greatest impact for industrially developed cities and individual Hot Spots are as follows:

- Minsk – Minsk vodokanal;

- Gomel – Gomel vodokanal;

- Mogilev – Mogilev “Khimvolokno”;

- Retchitsa – Retchitsa experimental-industrial hydrolytic plant;

- Mozyr – Mozyrsky petroleum refinery, etc.

All the 15 Hot Spots in question are the sources of negative impact on the nearby environmental features and this impact has adverse consequences.

7.2.1.6. Proven Negative Impact of Hot Spots

Our specialists carried out field observations at three Hot Spots, including the Gomel vodokanal, the Mozyrsky petroleum refinery and the Retchitsa experimental-industrial hydrolytic plant.  The observations identified evidence that these Hot Spots are the sources of negative impacts on biodiversity.  Detailed descriptions of the effects of effluent discharges from these enterprises are provided in Section 7.3. “Assessment of Results”.

7.2.2. Aquatic Fauna. Fish

7.2.2.1. Negative Impact of Hot Spots upon Fish Habitat

There are 46 species of fish known to occur in the basin of the Dnipro River.  The main types of desirable fish (sources of food) are as follows: bream, pike, pike perch, sazan, ide, cat-fish, perch, crucian and roach.  Desirable fish species formerly found in the basin but now rare or not present include: Russian sturgeon, sterlet, ordinary barbel, brook trout and vimba.  The four species of fish reported to be present (Red Book of the Republic of Belarus) in the Dnipro River and its tributaries are as follows:

- Sterlet (Acipencer ruthenus)

- Brook trout (Salmo trutta morpha fario)

- Ordinary barbel (Barbus barbus)

- Vimba vimba.

- Populations of these species of fish are qualified as rare or endangered.

The inventorying of fish resources is carried out through registration when the fishing crews deliver fish to storage or fish shops, normally these crews consist of 3 or 4 persons.  Fish caught by poachers and non-professional fishers are not counted.  According to the rayon (district) and oblast (state) fish inspectors, this quantity makes up approximately as much as the quantity of fish caught by fishing crews.

Statistics for commercial fish catches during the last 10 years give unambiguous evidence that here has been a general decrease in fish catches by approximately 30%.  This indicates that the state and the number of desirable fish in the Dnipro River and its tributaries are unsatisfactory.

Data regarding fish catches is recorded by the fisheries inspectors who join fishing crews.  The inspectors determine the size, weight and age-groups of various species of fish, as well as the proportion of young fish.  In addition they carry out special fry studies identifying species, numbers, weight and length of young fish.  Conclusions about the characteristics of the fish communities, the condition of their habitats and the prospects for expansion of exploitation are made on the basis of the data obtained.

No comparative data regarding the numbers and characteristics of young fish upstream and downstream of Hot Spots is available, however, comparative data for the sections of the rivers located upstream or downstream of some towns is documented. In these cases, the impact of all sources of river pollution present in the city on young fish is taken into consideration, as shown below.  To enable a comparison of the impacts of different cities using the data, those sections of the rivers upstream of the respective cities have been taken as 100%:

Number of young fish per 1 hectare upstream Orsha City  ¾ 100%

Number of young fish per 1 hectare downstream Orsha City  ¾ 48%

Number of young fish per 1 hectare upstream Mogilev City ¾ 100%

Number of young fish per 1 hectare downstream Mogilev City ¾ 62%

Number of young fish per 1 hectare upstream Mozyr City ¾ 100%

Number of young fish per 1 hectare downstream Mozyr City ¾ 53%

Biomass of young fish per 1 hectare upstream Orsha City  ¾ 100%

Biomass of young fish per 1 hectare downstream Orsha City  ¾ 48%

Biomass of young fish per 1 hectare upstream Mogilev City  ¾ 100%

Biomass of young fish per 1 hectare downstream Mogilev City  ¾ 64%

Biomass of young fish per 1 hectare upstream Mozyr City  ¾ 100%

Biomass of young fish per 1 hectare downstream Mozyr City  ¾  87%

It follows from these data that pollution of the Dnipro River and its tributaries by effluent discharges of industrial and communal enterprises adversely affect the numbers and biomass of young fish.  With regards to the decrease in biomass of young fish, at Orsha, this corresponds to a decrease in the number of fish by 52%, while at the nearby cities of Mogilev and Mozyr, the biomass falls more slowly than total number of young fish.

It should be noted that little data is available concerning fry studies and food fish catches.  In Annex D, Table D7, many Hot Spots have been assigned a score of 3 and 4 only due to the fact that there is no direct evidence of adverse impacts.  At the same time the expert is certain that the values at a level of 5 points would be justified provided that the missing data of fry studies was available and given the heavy metals present in the water of rivers downstream all 15 Hot Spots in question.

7.2.2.2. Fish Kills

In spite of systematic pollution of the sections of the rivers downstream of the Hot Spots no mass fish kills attributed to the Hot Spots have been registered.  Hence all the Hot Spots rated the lowest ranking (0) for this criteria (Annex D, Table D8).

7.2.2.3. Impact on Reproductive Function of Fish

The specialists attribute the decrease in the number and biomass of young fish to the pollution of the sections of the rivers by heavy metals, in particular zinc and copper (2-4 of maximum concentration limit), which adversely affect reproductive function of fish and young fish growing.

Annex D, Table D9, contains an assessment of the impact of Hot Spots on the reproductive function of fish.  It includes both fry and cases of fish leaving traditional spawning areas as a result of impacts from a Hot Spot as has been identified in the city of Retchitsa.  In this case, the meadows of the floodplain were the traditional spawning area for numerous species of fish (bream, sazan, roach, etc).  As a result of effluent discharge from wastewater treatment facilities of Retchitsa experimental-industrial hydrolytic plant to the Dnipro River, all the fish species with the exception of sazan ceased to spawn in this area.

In Annex D, Table D9, 5 points were assigned to those Hot Spots where there is proven direct evidence of their negative impact on the reproductive function of fish.  Availability of indirect evidence (presence of hazardous substances in the water) was qualified as 4 and 3 points.

7.2.3. Natural Species of Aquatic Fauna

7.2.3.1. Impact of Hot Spots on Benthic Species

Communities of benthic species are important indicators of the quality of their habitat.  In contrast to fish, which can leave polluted areas, benthic fauna are relatively immobile and the structure of species changes according to the quality of the surrounding water and sediments. 

Unfortunately, few studies of benthic species in the rivers of Belarus have been carried out with the objective of evaluating adverse impacts caused by specific Hot Spots.  As shown in Annex D, Table D10, the scores for this section were attributed to those Hot Spots where the results of such studies are available and there is proven direct evidence of a negative impact of the Hot Spots on benthic fauna (score of 5 points).  With regards to those Hot Spots where such studies were not undertaken but indirect data indicates that negative impacts may be occurring, a score of 2 points was assigned.  Where the expert believes that an investigation could provide direct evidence of negative impacts caused by the Hot Spot, a score between 2 and 5 points would be assigned.

7.2.3.2. Biotic Index

Annex D, Table D11 presents an assessment of Hot Spots according to the Woodiwiss biotic indices.  The Hydrometeorological Centre of Belarus has been carrying out long-term observations on the Hot Spots according to Woodiwiss biotic indices, but not exactly at the same points being analysed by this study.  These observations are being conducted near towns, as follows:

- Minsk - 10.0 km downstream of the city Woodiwiss Index is 4-6;

- Gomel - 13.7 km downstream of the city Woodiwiss Index is 2-5;

- Mogilev - 25.6 km downstream of the city Woodiwiss Index is 6-9;

- Borisov - 5.0 km downstream of the city Woodiwiss Index is 8;

- Bobruisk - 1.9 km downstream of the city Woodiwiss Index is 2-5;

- Svetlogorsk – 2.7 km downstream of the city Woodiwiss Index is 2-5;

- Mozyr – 45.5 km downstream of the city Woodiwiss Index is 2-5;

- Orsha – 0.5 km downstream of the city Woodiwiss Index is 9;

- Pinsk – 3.5 km downstream of the city Woodiwiss Index is 2.

The observations do not include such important sites as Retchitsa, Zhlobin, Slutsk and Soligorsk. As shown, the values of the Woodiwiss Indices can vary for the same spot subject to the season.

In Annex D, Table D11 the scores for Hot Spots were assigned with due regard to the above mentioned characteristics subject to the values of Woodiwiss Indices (dash (-) means that data are not available).  According to the data, Hot Spots located in of the cities of Mogilev, Orsha and Borisov discharge their effluent to the most pure water of the rivers of Dnipro and Berezina.  The most polluted water are registered in Pinsk.

7.2.4. Waterfowl

7.2.4.1. Negative Impact of Hot Spots on the Habitats of Waterfowl

Habitats of water birds, including rare and endangered species, are present in the vicinity of all of the Hot Spots.  The following species of rare and endangered waterfowl, recorded in the Red Book of the Republic of Belarus, are present in the Belarus portion of the Dnipro River basin:

- Black loom (Gavia arctica)

- Thick-knee (Burhinus oedicnemus)

- Small dabchik (Podiceps ruficollis)

- Big bittern (Botarus stellaris)

- Small bittern (Ixobrychus minutus)

- Pintail (Anas acuta)

- Scaup (Aythya nyroca)

- Big merganser (Mergys merganser)

- Grey crane (Grus grus)

- Big curlew (Numenius arquata)

- Small gull (Larus minutus)

- Small tern (Sterna albifrons)

- Grey dabchick (Podiceps grisena)

- Big egret (Egretta alba)

- Big eaglet (Aquila clanga)

- Black stork (Ciconia nigra)

- Ordinary golden-eye (Bucephala clangyla)

- Long-nosed merganser (Mergus serrator)

- Goldish plover (Pluvialis apricaria)

- Sandpiper-magpie (Haematopus ostralegus)

- Dunlin (Calidris alpina)

- Herring gull (Larus argentatus)

- Blue throat (Luscinia svecica)

- Red-neck dabchick (Podiceps auritus)

- Nycticorax nycticorax

- Orange heron (Ardea purpurea)

- Brand goose (Rufubrenta ruficollis)

- Eurasian wigeon (Anas penelope)

- Small sora (Porzana parva)

- Marsh sandpiper (Tringa stagnatilis)

- Lymnocripters minimus

- Reedwarbler (Acrocephalus paludicola)

- Hooping swan (Cygnus olor)

There is a lack of direct evidence linking the Hot Spots to negative impacts on the habitat of waterfowl.  There is, however, a lot of indirect evidence of possible negative impact.  This evidence is particularly strong with respect to aquatic animals and plants which serve as food for water birds and have been subjected to heavy metals contamination.  Therefore, almost all the Hot Spots in Annex D, Table D12 were assigned a score of 3 points. 

Another negative impact influenced by the Hot Spots is change of habitat.  This can result in birds being dislodged from their traditional nesting areas.  A typical example is the impact of effluents discharged from Berezovsk vodokanal through the Yaselda River to sedge lakes, which are the habitat of the reedwarbler, a globally endangered species.  Because the effluent is not fully treated, the sedge lake habitats have become degraded (becoming overgrown with reeds) and the reedwarbler seeks other habitat.  Therefore, the Berezovsk vodokanal was assigned a rating of 5 points.

7.2.4.2. Negative Impact on Migrant Birds

The Belarussian portion of the Dnipro River Basin is located at the intersection of two major flyways for migrant birds: Dneprovsky (North – South and South – North) and Polessky (West – East and East – West).  Both flyways are not defined only by the Dnipro and Pripyat Rivers specifically, but cover large territories several tens of kilometers wide around the rivers.  The wide floodplains of the Dnipro and Pripyat Rivers, often flooded in the spring, as well as their tributaries, numerous former riverbeds, lakes, and meadows flooded in the periods of high water, are of great importance for migrant waterfowl. Water birds tire after their long migration and use these areas for rest and feeding (1-2 weeks and even longer).  While the ultimate destination for most migratory waterfowl along this flyway is their nesting habitat in northern Russia, some birds stay in Belarus for nesting. 

All the Hot Spots in Annex D, Table D13 were assigned scores of 4 and 5 points as they are located in the flyways used by migrant birds in the spring and autumn.  The greatest gatherings of birds are observed at submerged areas of floodplains, floodplain lakes and former riverbeds as well as in rivers and creeks.  These areas are nearby every Hot Spot.

7.2.5. Plants

7.2.5.1. Negative Impact of Hot Spots on Plants

The basin of the Dnipro River is the habitat of the following species of plants, recorded in the Red Book of the Republic of Belarus:

- Big horse-tail (Eqisetum telmateia)

- Floating salvinia (Salvinia nanans)

- Water-lily (Nimphea alba)

- Water chestnut (Trapa natans)

- Small caulinia (Caulinia minor)

- Big naiad (Najas major)

- Aldrovanda vesiculous (Aldrovanda vesiculosa)

The first assessment of the presence of contaminants in higher aquatic plants (macrophytes) was carried out in Belarus in 2000.  It was determined that the rate of accumulation of contaminants in the plants was dependent on the contaminant concentration and the рН of the water.

The assessment program identified the selective absorption of various elements by various species of plants.  For example, plantain accumulated up to 40 mg/kg of nickel dry substance which exceeds by a factor of 135 the national average background concentration of nickel in macrophytes.  The highest concentrations of nickel were identified in macrophytes in the vicinity of Minsk, Mogilev and Gomel.

The maximum concentration of copper was observed in Susak umbelliferous (up to 135 mg/kg of dry substance), exceeding by a factor of 28, the average background concentration of copper in macrophytes.  The highest level of contamination of macrophytes by copper was identified in the vicinity of Gomel and Mogilev.

The maximum concentration of lead was identified in macrophytes in the same cities.  Reeds accumulated lead 250 times more than the background concentration. 

The concentrations of chromium in macrophytes (pondweed, Ceratophyllum, etc.) near Mogilev and Gomel were found to be 125 times higher than the national average. 

The greatest accumulation of zinc was revealed in such macrophytes as Canadian “Elodia” and pectinated “shtukenia”, both near Mogilev, at levels exceeding the average background concentration by 70 to 125 times.

A similar situation was observed with the accumulation of manganese, vanadium and titanium. 

The highest capacity for accumulation of elements from Hot Spots was observed in submerged macrophytes – Characeae algae, Elodia, Ceratophyllum, pondweed, etc.  These same species which are found in non-polluted water bodies contain chromium, copper, nickel, lead, titanium and zinc, at the levels equivalent to background concentrations.

With respect to the above, Annex D, Table D14 presents the assessment of the impact of the Hot Spots on the aquatic plants.  Those Hot Spots where experimental data with regard to the content of heavy metals in macrophytes were available were assigned 5 points.  The other Hot Spots were assigned 3 points given the lack of direct evidence, but the likelihood of adverse affects based on indirect evidence.