scholarly journals Seagrass of Vasiliko Bay, Eastern Mediterranean: Lost Cause or Priority Conservation Habitat?

2020 ◽  
Vol 8 (9) ◽  
pp. 717
Author(s):  
Demetris Kletou ◽  
Periklis Kleitou ◽  
Ioannis Savva ◽  
Martin J. Attrill ◽  
Stephanos Charalambous ◽  
...  

Mediterranean coasts are affected by multiple mounting pressures. In Cyprus, marine fish farming has grown rapidly in the past decade and is concentrated in the west side of Vasiliko Bay. The east coast of this bay has ports, a power station, a desalination unit, a cement factory, a major new oil terminal, and gas storage facilities. The bay is earmarked to create the largest hydrocarbon processing, storing, and transport facility in the region. Here, we assess the status of Posidonia oceanica habitat in an understudied region at the upper thermal, and eastern limit, of this Mediterranean endemic seagrass. An extensive ancient seagrass meadow was revealed, covering about 200 ha across 10 km of coastline, over soft substrata at ca 10–30 m depth, and over hard substrata at ca 0–6 m depth. Seagrass shoot density and leaf surface area decreased, both with increasing depth and with proximity to industrial developments; part of the meadow had been destroyed by dredging to build a jetty. Close to fish farms the seagrass had higher epiphytic biomass as well as lower leaf number, mass, and surface area, all of which indicate adverse effects of eutrophication and increased turbidity. Despite these multiple stressors, most of the meadow was in good ecological status, with some of the highest shoot densities ever reported. Furthermore, iconic species like sea turtles, monk seals, and dolphins were seen during sampling. Posidonia oceanica meadows off Cyprus are among the most valuable in the Mediterranean due to their tolerance of high seawater temperatures. Managers of future coastal developments in the region will need to adhere to European legislation and international conventions designed to secure the socioeconomic benefits of seagrass beds.

Author(s):  
Giancarlo Bellissimo ◽  
Benedetto Sirchia ◽  
Vincenzo Ruvolo

The present paper aims to assess for the first time the ecological status of the Sicilian water bodies using the PREI (Posidonia oceanica Rapid Easy Index) method according to the Water Framework Directive (WFD, 2000/60/EC) requirements. The PREI is based on five metrics: shoot density, shoot leaf surface area, E/L ratio, depth of lower limit, and type of this lower limit. Monitoring of the 29 P. oceanica meadows allowed to classify the 20 WBs of Sicilian coasts in the first two levels of status: 10 as “high” and 10 as “good” with the PREI values ranged between 0,551 and 1.


2008 ◽  
Vol 65 (8) ◽  
pp. 1492-1497 ◽  
Author(s):  
Yolanda Fernández-Torquemada ◽  
Marta Díaz-Valdés ◽  
Francisco Colilla ◽  
Beatriz Luna ◽  
José Luis Sánchez-Lizaso ◽  
...  

Abstract Fernández-Torquemada, Y., Díaz-Valdés, M., Colilla, F., Luna, B., Sánchez-Lizaso, J. L., and Ramos-Esplá, A. A. 2008. Descriptors from Posidonia oceanica (L.) Delile meadows in coastal waters of Valencia, Spain, in the context of the EU Water Framework Directive. – ICES Journal of Marine Science, 65: 1492–1497. Evaluations are provided of 21 descriptors of Posidonia oceanica meadows along the coast of Valencia, Spain, with a view to using these in implementing the European Water Framework Directive (WFD). The descriptors selected are known to respond to a variety of anthropogenic disturbances. Data were collected at 17 locations during three consecutive years. A principal components analysis was used to classify the ecological status of each locality according to five classes as prescribed by the WFD. To identify the descriptors that contributed most to similarity among localities within each class and to dissimilarity between adjacent classes, a similarity percentage analysis was performed. We also correlated the descriptors with an independent set of indicators for various types of anthropogenic pressures on the water bodies associated with the different localities. The descriptors providing the most consistent information on status as well as demonstrating a significant relationship with estimated pressures were: shoot density, shoot foliar surface, dead-matte cover, meadow cover, herbivore pressure, rhizome baring/burial, foliar necrosis, percentage of plagiotropic rhizomes, and leaf-epiphyte biomass.


Aquaculture ◽  
1997 ◽  
Vol 158 (1-2) ◽  
pp. 85-94 ◽  
Author(s):  
Arne Ervik ◽  
Pia Kupka Hansen ◽  
Jan Aure ◽  
Anders Stigebrandt ◽  
Per Johannessen ◽  
...  

2017 ◽  
Vol 18 (1) ◽  
pp. 161 ◽  
Author(s):  
V. GERAKARIS ◽  
P. PANAYOTIDIS ◽  
S. VIZZINI ◽  
A. NICOLAIDOU ◽  
A. ECONOMOU-AMILLI

Biotic indices are considered key assessment tools in most national and European policies aimed at improving the quality of coastal waters. At present, several Water Framework Directive (WFD)-compliant biotic indices based on the marine angiosperm Posidonia oceanica have been developed and applied in the Mediterranean Sea. In this study, we investigated the effectiveness of four different P. oceanica indices (POMI, PREI, Valencian CS, and BiPo) in evaluating the ecological status of coastal waters in a case study area of Greece. The evaluation, comparison, and validation of the Ecological Status Class (ESC) assessments obtained by each index were based on a set of eight common sites that encompasses the maximum range of environmental quality in the study area. Four sampling sites separated by tens of km were chosen in each of the two water bodies (WBs) studied. The spatial variations of the features of P. oceanica meadows were examined according to a hierarchical sampling design across four spatial scales, ranging from metres to tens of km, using independent nested analysis of variance. Except for the BiPo index, the reference values for each metric/index were defined by the dataset available for the study area. All biotic indices classified the WBs of the study area in Good ESC category. Only three of the four indices (PREI, Valencian CS, and BiPo) showed high comparability in the assessment of ESC at study site level. It is assumed that the differences found in the remaining index (POMI) are due to the different type of metrics taken into consideration and the different weighting given to them. Our findings suggest that all indices can provide an overall view of the cumulative impact of multiple environmental stressors existing in the study area, and can thus help raise awareness of ecosystem degradation.


2017 ◽  
Vol 23 (2) ◽  
Author(s):  
NAVALSINGH J. TODAWAT

Sooty mould diseases of Tress from Aurangabad district were surveyed. During the survey of tress, 5 species were found infected by fungal pathogens causing sooty mould diseases. Disease is easily identifiable by the presence of a black, velvety growth covering the leaf surface area. The fungus produces mycelium which is superficial and dark grows on the flowers, leaf, stem and sometime on fruits also. The severity of disease depends on the honeydew secretions by insects. The diseases were found to be caused by 5 species of fungi viz. Capnodium anonae, C. ramosum, Capnodium sp., Meliola bangalorensis and Meliola ranganthii.


Author(s):  
M. G. Markova ◽  
E. N. Somova

Work on going through the adaptation stage of rooted micro-stalks comes down to searching for new growth regulators and studying the influence of external conditions, which include, among other things, light effects. The data of 2018-2019 on the effect of growth regulators Siliplant, EcoFus and experimental LED phytoradiators on the adaptation of rooted micro-stalks of garden strawberries (Fragaria x ananassa duch) in vivo are presented. The object of research is rooted micro-stalks of garden strawberries of the Korona variety. It was revealed that, at the adaptation stage of rooted micro-stalks of strawberries, the most effective was the treatment of plants by spraying with Siliplant at a concentration of 1.0 ml/l and the combined treatment with Siliplant and EcoFus at concentrations of 0.5 ml/l: regardless of lighting, the survival rate averaged 99.4 - 99.7%, the leaf surface area increased significantly from 291.85 mm2 to 334.4 mm2. The number of normally developed leaves of strawberry microplants increased significantly after treatment with all preparations from 3.5 to 6.0, 5.8 and 6.5 pcs/plant, and a significant increase in the height of strawberry rosettes was facilitated by treatment with Siliplant and Siliplant together with EcoFus. Regardless of growth regulators, the most effective was the experimental LED phyto-irradiator with a changing spectrum, which contributed to an increase in leaf surface area, height of rosettes and the number of normally developed leaves in strawberry microplants. When illuminated with a flashing phytoradiator, these indicators are lower than in the control version, but not significantly. By the end of the rooting stage, all microplants of garden strawberries corresponded to GOST R 54051-2010.


1995 ◽  
Vol 31 (10) ◽  
pp. 73-84 ◽  
Author(s):  
T. M. Iversen

The main environmental problems associated with fish farming in Denmark are attributable to the dam, the “dead reach” and nutrient and organic matter discharge. The environmental regulation of fish farming in Denmark started with the Environmental Protection Act of 1974, the Statutory Order of 1985 forbidding wet feed, and the Action Plan on the Aquatic Environment of 1987. In the case of freshwater fish farms, the latter was implemented through the measures stipulated in the 1989 Statutory Order on Fish Farms. The impact of Danish legislative measures to reduce and regulate the environmental effects of freshwater fish farms can be summarized as follows: - the number of fish farms has been reduced from about 800 in 1974 to about 500 at present; - production has tripled since 1974 and has been stable since 1989; - a change from wet to dry feed has reduced the environmental impact of the farms; - the national goals of the Action Plan on the Aquatic Environment of 1987 for reducing fish farm discharges of organic matter, nitrogen and phosphorus have been fulfilled. The main remaining problems are that: - the local impact of fish farms on downstream stream quality is still much too high in about 15% of cases; - the problem of the passage of migrating invertebrates and fish is still unsolved at some farms; - the problems posed by “dead reaches” are still unsolved. It is concluded that sustainable fish farming is possible in Denmark, but with the present technology production will have to be significantly reduced.


1995 ◽  
Vol 31 (10) ◽  
pp. 61-71 ◽  
Author(s):  
M. Enell

During the last 20 years there has been an interesting development of the Nordic fish farming, with regard to the feeding and farming technology and to the increase in production quantities. During the period 1974-1994 the production increased from 15,800 to about 250,000 tonnes/year. In 1974 the major part of the production was in Denmark, and in 1994 the major part was in Norway. The nutrient impact of fish farming on surrounding sea areas is mainly a function of the feed coefficient, the feed composition and metabolic processes in the fish. The comprehensive development of the feed composition and the feeding technology has resulted in reduced load of unmetabolized nutrients from fish farms, calculated per tonne fish produced. In 1974 the mean Nordic feed coefficient was 2.08 and in 1994 the coefficient was 1.25. Feed coefficients of 1.0-1.1 are now reported for Danish and Norwegian freshwater and marine fish farms. The nitrogen (N) and phosphorus (P) content of the feed has decreased, in addition the quality of the nutrient substances in the feed has changed, especially for N. The N content has decreased from 7.8 to 6.8% during the period 1974-1994 and the content of P has decreased from 1.7 to 0.7% during the same period. This development of the feed coefficient and the feed composition has resulted in a present load from a typical Nordic fish farm of 55 kg N and 4.8 kg P/t fish produced. The figures for 1974 were 132 kg N and 31 kg P/t fish produced. The Nordic fish farming production in 1994 resulted in a load of about 13,750 t N and about 1,200 t P on the actual recipients. The load from the Swedish, Finnish and Danish fish farming operations, with the Baltic Sea and the Skagerrak as the recipients, is negligible in comparison with other pollution sources. The quantities of N and P from the fish farming are equal to 0.5% of the atmospheric deposition on the sea surface and 3% of the atmospheric P load. Norwegian, Icelandic and the Faroe Islands fish farming operations are using the North Sea and the Norwegian Sea as the recipients. However, the nutrient load from single fish farms in certain coastal and inland water bodies can be significant and must be considered in the impact assessment together with other sources.


Author(s):  
F. A. Altayeva

The article presents the results of growing tilapia to marketable weight in experimental sites (Chilikskoye pond pond farms LLP, KATU named after S. Seifullin JSC and Kapshagai spawning farm — 1973 LLP). In the process of carrying out research works, the methods generally accepted in fish farming, hydrochemistry, hydrobiology, hydrology, ichthyology, as well as foreign normative and technical guidelines and methodological instructions on the technology of growing commercial tilapia in industrial conditions were used. Monitoring of hydrochemical analyses of water in ponds, swimming pools, and closed water supply installations is given. Fish-breeding and biological indicators of tilapia grown in various experimental conditions are presented. The results of the studies have shown the real possibility of growing tilapia in various conditions of fish farms in Kazakhstan. Based on the results of the work, the following conclusions were made: — satisfactory fish-breeding indicators were obtained with various cultivation technologies (as when growing tilapia in polyculture and monoculture in ponds, in pools, as well as cultivation in the recirculation system); — the cultivation of tilapia in the experimental ponds of the fish farm of the Almaty region of the Republic of Kazakhstan has shown the possibility of obtaining high fish-breeding biological indicators of tilapia and the ability to grow to marketable mass in a short time; — as a result of experimental cultivation in various conditions, it was found that the survival rate was not lower than 97%; — as a result of the analysis of the profitability indices of the developed technologies, it was found that the most profitable was the technology of growing marketable tilapia products in monoculture ponds on water with a natural thermal regime in Chilik Pond Economy LLP.


Author(s):  
A. M. Naumova ◽  
◽  
L. A. Rozumnaya ◽  
A. Yu. Naumova ◽  
L. S. Loginov ◽  
...  

The influence of ecological, epizootological and technological factors on fish health was studied. It is shown that disregard of environmental, technological and veterinary-sanitary requirements in the reproduction and cultivation of fish leads to the emergence of contagious and non-contagious diseases and causes significant damage to fish farming. The analysis of previously approved veterinary and sanitary rules, instructions, recommendations for breeding and commercial fish farms, as well as patent documentation and scientific publications in the field of ecological and veterinary research in fish farming is carried out. The possibility of using modern ecological and veterinary-sanitary achievements for the protection of fish health is shown. The complex system of preventive measures (organizational, environmental-technological and veterinary-sanitary), supplemented by modern ecological and veterinary achievements, in its implementation will allow to reduce losses of fish products and increase efficiency of production.


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