Online Version ISSN: 1314-412XVolume 5, Number 1

March 2013

2013

Scope and policy of the journalAgricultural Science and Technology /AST/ – an International Scientific Journal of Agricultural and Technology Sciences is published in English in one volume of 4 issues per year, as a printed journal and in electronic form. The policy of the journal is to publish original papers, reviews and short communications covering the aspects of agriculture related with life sciences and modern technologies. It will offer opportunities to address the global needs relating to food and environment, health, exploit the technology to provide innovative products and sustainable development. Papers will be considered in aspects of both fundamental and applied science in the areas of Genetics and Breeding, Nutrition and Physiology, Production Systems, Agriculture and Environment and Product Quality and Safety. Other categories closely related to the above topics could be considered by the editors. The detailed information of the journal is available at the website. Proceedings of scientific meetings and conference reports will be considered for special issues.

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Editor-in-Chief

Tsanko YablanskiFaculty of AgricultureTrakia University, Stara ZagoraBulgaria

Co-Editor-in-Chief

Radoslav SlavovFaculty of AgricultureTrakia University, Stara ZagoraBulgaria

Editors and Sections

Genetics and Breading

Atanas Atanasov (Bulgaria)Ihsan Soysal (Turkey)Max Rothschild (USA)Stoicho Metodiev (Bulgaria)

Nutrition and Physiology

Nikolai Todorov (Bulgaria)Peter Surai (UK)Zervas Georgios (Greece)Ivan Varlyakov (Bulgaria)

Production Systems

Dimitar Pavlov (Bulgaria)Dimitar Panaiotov (Bulgaria)Banko Banev (Bulgaria)Georgy Zhelyazkov (Bulgaria)

Agriculture and Environment

Georgi Petkov (Bulgaria)Ramesh Kanwar (USA)

Product Quality and Safety

Marin Kabakchiev (Bulgaria)Stefan Denev (Bulgaria)Vasil Atanasov (Bulgaria)

English Editor

Yanka Ivanova (Bulgaria)

Online Version ISSN: 1314-412X

2013

Volume 5, Number 1March 2013

Environmental studies of the macrozoobenthos in the nearby coastal zone along the Bulgarian Black Sea coast

E. Petrova*, S. Stoykov

Institute of Fishing Resources, 4 Primorski, 9000 Varna, Bulgaria

Abstract. The interest in studies of the nearby coastal zone of the Black Sea is great because it is the most productive section of the basin. The variety of habitats, water aeration, good temperature and density of nutrients coming from the nearest land and littoral contribute to the development of intensive life in it. In this area there are representatives of almost all groups of benthic organisms with the exception of some deep species. At the same time proximity to the coast makes it the most polluted part of the sea. Following the EU requirements pollutants are greatly reduced, which affects favourably biodiversity in the Black Sea ecosystem. 77 taxa of macrozoobenthos species were established, divided into four main groups: Polychaeta, Mollusca, Crustacea and "Diversa". The ecological status is calculated on the Index of species diversity (H'), marine biotic index (AMBI) and multivariate Marine Biotic Index (M-AMBI). The results of the studies of macrozoobenthos from north to south in the nearby coastal area tend to improve the ecological situation in comparison with previous periods.

Keywords: marine environment, Black Sea, nearby coastal zone, macrozoobenthos, biodiversity, ecological status

AGRICULTURAL SCIENCE AND TECHNOLOGY, VOL. 5, No 1, pp 111 - 114, 2013

Statistical analyses to assess the ecological status:Introduction�Shannon community diversity index (H') (Shannon and

Weaver, 1963) for determining the ecological status of water bodies The nearby coastal zone is the most polluted part of the sea. with muddy sediments and water bodies with sandy and mixed The main reason is the proximity of land from which rain water sediments.entering through rivers and pollutants from the industrial character of

�Marine Biotic Index (AMBI) to assess the ecological status of agriculture and everyday activities of people. Due to the coastal the benthos using the border definitions developed by Borja et al. current directed from north to south at distance 1 mile from the sea (2000, 2003) and Muxica et al. (2005).shore these pollutants are distributed along the Bulgarian coast. The

�Multivariate AMBI (M-AMBI) was applied with the default two major ports and vessel traffic increased pollution of coastal EQR boundaries according to Borja et al. (2006).waters with oil. This zone creates conditions for phytoplankton

For classifying the ecological status of the stations in the nearby blooms leading to reduction of oxygen content in water, which coastal zone the principle "one out - all out" is used, i.e. the worst negatively impact benthic organisms, especially attached forms.value of each station is considered final.Following the EU requirements pollutants into the waters of the

Danube and other rivers flowing into the Black Sea are greatly reduced. There is a reduction of pollution from local sources. Many factories have stopped their activities, due to their low economic Results and discussion indicators. This led to the improvement of the status of biodiversity in the Black Sea ecosystem (Tokarev and Shulman, 2007).

Species compositionDuring the survey 77 species were identified distributed in four

main groups: Polychaeta, Mollusca, Crustacea and mixed “Diversa” Material and methods (Table 1). Graphical representation of the percentage of different

groups is presented in Figure 1. The type of sediment at the different Studies of macrozoobenthos in the nearby coastal zone were stations confirms that one part of the samples are collected at the

carried out with R/V "Prof. Al. Valkanov" on 21 stations from north to border between littoral and sublittoral zone and the second part south at a distance 1 mile from the sea shore. The sampling was within sublittoral. From the established 77 species – 13 have

2made by “Van-Veen” grab with opening mouth 1/10 m . The coefficient of occurrence higher than 50%, 13 species between 50 materials were sieved on the shipboard through a couple of sieves and 25%, while the remaining 51 species are with less than 25%. and preserved in 4 % formaldehyde. A total of 63 macrozoobenthos samples were taken (21 samples x 3 replicates). In laboratory taxonomic identification of the species composition was performed (Morduhay-Boltovskoy 1968, 1969, 1972; Marinov, 1977), determining the quantitative characteristics (abundance and biomass), quantitative parameters are treated as an area of 1 square metre.

111

* e-mail: elitssa@yahoo.com

Table 1. Macrozoobenthos groups and number of species

Macrozoobentos groups

Polychaeta

Mollusca

Crustacea

“Divеrsa”

28

19

21

9

Number/species

The highest percent of occurrence from polychaets is for species from genus Nepthys and Capitella minima. These species lives in sandy and sandy-mud type of sediment. From group of Mollusca with highest percent are Chamelea gallina and Spisula subtruncata.

2In the species composition were established some invasive value was observed at Station Varna Bay-South – 216 ind/m . In the molluscs for Black Sea like Mya arenaria, Anadara inaequivalvis and region of cape Maslen is registered good food base, which allows Rapana venosa. The rapana is single in the Bulgaria export list like successful cultivation of black mussels (Mytilus galloprovincialis) in marine non-fish resources. this area (Nikolov et al., 2010).

Abundance. Biomass. The overall average density of macrozoobenthos equals 741

2 The total average biomass of macrozoobenthos in the research ind/m , which is distributed in groups as follows: Polychaeta – 405 2

2 2 2 area amounts to 259, 43 g/m . It is made up of four groups discussed ind/m , Mollusca – 204 ind/m , Crustacea – 71 ind/m and “Diversa” – 2 2

2 above: Polychaeta – 7,76 g/m , Mollusca – 225, 034 g/m , Crustacea 61 ind/m (Figure 2). The figure shows that dominant in the number 2– 21,752 g/m (Figure 4). From the figure it is clear that the biomass are the groups of Polychaeta and Mollusca. High density show

of macrozoobenthos in the nearby coastal area is built mainly of Melinna palmatа, Nephtys cirrosa, Nepthys hombergii, Chamelea 2molluscs. High biomass show Chamelea gallina – 29,65 g/m and gallina and Anadara inaequivalvis. The density of macrozoobenthos

2Anadara inaequvalvis – 15,58 g/m . Even with a less dense species groups by stations is shown in Figure 3. The highest density was 2 Mytilus galloprovincialis occurs at few stations with very high registered on Station Albena – 2223 ind/m due to the high number of

2 2biomass – 1006,3 gr/m (Krapec ІІ replicate), 1748, 96 gr/m (Krapec polychaetes species Melinna palmata, followed by Station Maslen 2 22 2 ІІІ replicate), 1463,47 gr/m (Varvara ІІІ replicate) and 1544,8 gr/m nos – 1367 ind/m and Station Shabla – 1163 ind/m and the lowest

112

Figure 1. Percentage of the macrozoobenthos groupsconstituting the species composition, September, 2011

PolyvhaetaMolluscaCrustacea“Diversa”

12%

36%

25%

27%

Figure 2. Average density of macrozoobenthos by groups ina nearby coastal area, September 2011

abundance

“Diversa”

450

400

350

300

250

200

150

100

50

0Polychaeta Mollusca Crustacea

2Figure 3. Density (ind/m ) of macrozoobenthos in stations and groups, in September 2011

PolyvhaetaMolluscaCrustacea“Diversa”2500

2000

1500

1000

500

0

Krape

ts

Krape

ts*

Shabla

Rusalk

a

Kaliak

ra

Balchik

Albena

Vbnor

th

Vbsou

th

Galata

Kamch

ia

Dvoini

ca

Neseb

ur

Koketr

ais

Burga

s 2

Sarafo

vo

Rosen

ets

Soozo

pol

c. Mas

len

Varva

ra

Veleka

Figure 5. Biomass (ind/ ) of macrozoobenthos in stations and groups, in September 20112m

PolyvhaetaMolluscaCrustacea“Diversa”1200

1000

800

600

400

200

0

Krape

ts

Krape

ts*

Shabla

Rusalk

a

Kaliak

ra

Balchik

Albena

Vbnor

th

Vbsou

th

Galata

Kamch

ia

Dvoini

ca

Neseb

ur

Koketr

ais

Burga

s 2

Sarafo

vo

Rosen

ets

Soozo

pol

c. Mas

len

Varva

ra

Veleka

Figure 6. H'and AMBI in the nearby coastal area, September 2011

Krape

ts

Krape

ts*

Shabla

Rusalk

a

Kaliak

ra

Balchik

Albena

Vbnor

th

Vbsou

th

Galata

Kamch

ia

Dvoini

ca

Neseb

ur

Koketr

ais

Burga

s 2

Sarafo

vo

Rosen

ets

Soozo

pol

c. Mas

len

Varva

ra

Veleka

4.5

4

3.5

3

2.5

2

1.5

1

0.5

0

H'

AMBI

113

(Veleka ІІ replicate). Viewed by stations the biomass is shown in Figure 5. The figure shows that at all stations the biomass is built mainly by Mollusca species. The indices of Shannon-Weaver, AMBI and M-AMBI were calculated. Index values and ecological status of stations in the nearby coastal zone are shown in Figure 6 and Figure 7. M-AMBI index is an accurate tool for assessing the ecological status, as it integrates environmental sensitivity and diversity.

Results for the ecological status in the 1 mile zone along the Bulgarian Black Sea coast, shows that 11 of the stations come in good ecological status. Status of moderately polluted possess Albena, Varna Bay–North, Varna Bay–South, Kamchya, Dvoynitsa, Nessebar, Rosenets, Sarafovo. The most likely reason is the influx of pollutants from rivers or polluted water from Varna lake system. The exception is station Burgas Bay, which is classified as having poor status.

Figure 4. Average biomass of macrozoobenthos by groupsin a nearby coastal area, September 2011

250

200

150

100

50

0Polychaeta Mollusca Crustacea “Diversa”

biomass

114

marine ecological quality assessment: the usefulness of Conclusionsmacrobenthic communities in an area affected by a submarine outfall. ICES CM 2003/Session J-02, Tallinn, Estonia, 24-28 As a result of studies of macrozoobenthos in the nearby coastal September. area in September 2011 a total of 77 taxa were drawn. The highest Borja A, Franco J and Pérez V, 2000. A marine biotic index to percentage – 36% is for Polychaeta group, followed by Crustacea – establish the ecological quality of soft bottom benthos within 27%, Molluscs – 25% and finally the group Diversa – 12%. From the European estuarine and coastal environments. Marine Pollution established 77 species – 13 have coefficient of occurrence higher Bulletin, 40, 12, 1100-1114. than 50%, 13 species between 50% and 25%, while the remaining Marinov Т, 1977. Fauna of Bulgaria, 6, Polychaeta, Sofia, BАS, 257 51 species are with less than 25%. The overall average density of

2 pp.macrozoobenthos comprises 741 ind/m and the average biomass 2 Morduhay-Boltovskoy MD, (Ed.), 1968. A key to Black Sea and in the research area amounts to 259,43 g/m .

Azov Sea fauna, I, Kiev, Naukova Dumka, 437 pp. Based on the results the ecological status of the nearby coastal Morduhay-Boltovskoy MD, (Ed.), 1969. A key to Black Sea and area indicates that the majority of stations (11 in total) fall into a good Azov Sea fauna, III, Kiev, Naukova Dumka, 340 pp. status. Moderately polluted are eight stations and one classified as Morduhay-Boltovskoy MD, (Ed.), 1972. A key to Black Sea and poor status. The most likely reason is the influx of pollutants from Azov Sea fauna, l. II, Kiev, Naukova Dumka, 536 pp. rivers or polluted water from Varna lake system. Muxika I, Borja Á and Bonne W, 2005. The suitability of the marine The investigations of macrozoobenthos in the nearby coastal biotic index (AMBI) to new impact sources along European coasts. area from north to south show a trend of improving the ecological Ecological Indicators, 5, 19-31. situation in comparison with research in the previous periods.Nikolov G, Atanasov A, Georgiev D and Raichev E, 2010. Analysis of the Plankton in the Area around the Cape Maslen Nos, Bulgaria: Possibilities for Cultivation of Mediterranean Mussels References(Mytilus galloprovincialis), Ecologia Balkanica. International Scientific Research Journal of Ecology, 2, pp.15-18.Borja A, Josefson AB, Miles A, Muxika I, Olsgard F, Phillips G, Shannon CE and Weaver W, 1963. The mathematical theory of Rodríguez JG and Rygg B, 2006. An approach to the communication, University Illinois Press, Urbana, 117 pp.intercalibration of benthic ecological status assessment in the North Tokarev Y and Shulman G, 2007. Biodiversity in the Black Sea: Atlantic ecoregion, according to the European Water Framework effects of climate and anthropogenic factors. Hydrobiologia, 580, 1, Directive. Marine Pollution Bulletin (in press). 23-33.Borja A, Franco J and Muxika I, 2003. Classification tools for

Figure 7. M-AMBI in the nearby coastal area, September 2011

M-AMBI

1

0.9

0.8

0.7

0.6

0.5

0.4

0.3

0.2

0.1

01 2 3 4 5

High

Bad

Good

Moderate

Poor

6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21

Stations

Review

Status of remote hybrids in the Poaceae: problems and prospectsH. Stoyanov*

Genetics and Breeding

Genetic divergence among accesions of coriander (Coriandrum sativum L.)N. Dyulgerov, B. Dyulgerova

Yield stability of contemporary Bulgarian winter wheat cultivars (Triticum aestivum L.) in DobrudzhaP. Chamurliyski, N. Tsenov

Assessment of initial material for stevia (Stevia rebaudiana B.) breedingTz. Kikindonov

Grain yield of winter feed barley varietiesB. Dyulgerova, D. Dimova, D. Valcheva, D. Vulchev, T. Popova, M. Gocheva

A study on the biological and economic qualities of common winter wheat (Triticum aestivum L.)I. Stankov, S. Tsvetanov, P. Stankova, I. Yanchev, T. Raycheva

Nutrition and Physiology

Drought–induced changes in photosynthesis of young cowpea plantsK. Uzunova, Z. Zlatev

Effect of organic fertilizers on photosynthesis of young tomato plants (Lycopersicon esculentum Mill.)Z. Zlatev, V. Popov

Production Systems

Productivity of sunflower grown in a periodic water deficit conditionsR. Petrova, A. Matev, H. Kirchev, A. Sevov

Variation of capillary rise of water in the slightly leached chernozem soil of Dobrudzha region under the effect of long-term use of some soil tillage practicesP. Yankov

Influence of the variety and sowing rate on the green mass productivity of Sudan grass and Sorghum x Sudan grass hybridsTz. Kikindonov, S. Enchev, K. Slanev

Effect of the irrigation regime on the productivity of root celery by drip irrigation in the Plovdiv regionB. Harizanova-Petrova, A. Ovcharova

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Study of a zeolite–water experimental refrigeration module intended for animal raisingR. Georgiev, K. Peichev, A. Pavlov, K.Trendafilov, G. Dineva, I. Binev

Method for rapid determination of the percentage rate of grain losses by the combine harvester according to its parametersN. Delchev, K. Trendafilov

Phase–frequency characteristics of three types of milking clusters with a different volume and shape of the pulsation chamberB. Banev, K. Peychev, V. Vlashev, G. Dineva

Nondestructive (NIRS) determination of some technological traits of Bombyx mori L. cocoonsM. Panayotov, S. Atanassova, S. Petrova

Researching the resistance of bees fattened up with additive of extract of Tribulus terrestris L. during winteringI. Hristakov, I. Zhelyazkova, V. Hvarchilkov

Influence of liming with Ca(OH) on nitrogen, phosphorus and potassium content in foliage of vine 2

varietiesK. Trendafilov, V. Valcheva, S. Todorova

Content and composition of the essential oil of Rosa alba L. during flower developmentA. Dobreva, M. Gerdzhikova

Effectiveness of application of the leaf–fertilizers Hortigrow in sweet basil (Ocimum basilicum var. glabratum)V. Ivanov, I. Yanchev, T. Raycheva, K. Stoyanov

Agriculture and Environment

M. Lacheva

Agroclimatic conditions of existence of almond trees in Plovdiv region during the winter periodD. Ivanova, N. Shopova

Phytoplankton growth and chlorophyll – a content in the surface layer of the Bulgarian Black Sea coastal waters in 2011D. Petrova, D. Gerdzhikov

Ecological status of Varna Bay through the state of phytoplankton, macrozoobenthos and macrophytes during the autumn of 2011D. Petrova, E. Petrova, D. Gerdzhikov, V. Vachkova, R. Bekova

Environmental studies of the macrozoobenthos in the nearby coastal zone along the Bulgarian Black Sea coastE. Petrova, S. Stoykov

A study of macromycetes in Maglenishki Rid, Eastern Rhodopes Mts. II. Recent data of study

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Product Quality and Safety

Evaluation of pork meat quality and freshness using colorimetric and spectral methodsS. Atanassova, T. Stoyanchev, S. Ribarski

Reducing the hyperspectral feature spaces of ready-to-cook minced meat productsK. Kolev

Effect of cold storage terms on physico-chemical characteristics of Japanese quail (Coturnix coturnix japonica) meatS. Ribarski, A. Genchev, S. Atanasova

The flavonoid content in the white oil–bearing rose (Rosa alba L.)A Dobreva, M Gerdzhikova

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thmance in dairy cows,IX International Conference on Production Diseases in Farm Animals, Sept.11 – 14, Berlin, Germany, p. 302 (Abstr.).Thesis:Penkov D, 2008. Estimation of metabolic energy and true digestibility of amino acids of some feeds in experiments with muscus duck (Carina moshata, L). Thesis for DSc. Agrarian University, Plovdiv, 314 pp.

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Volume 5, Number 1March 2013