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Open access

Daria Sikorska, Piotr Sikorski and Piotr Hewelke

Protection of valuable water dependent ecosystems in urban areas

Water dependent ecosystems are habitats most vulnerable to urbanization pressure. There are not many such habitats in Warsaw. Those which remained are mostly dewatered sites existing within green areas such as parks. Habitats with peat and moorsh soils have a unique value, thus there is a rational need for detailed research and evaluation to preserve them. This paper is a case-study of two different water dependent ecosystems, localized within the boundaries of Poland's capital city, both remaining under strong urbanization pressure. Different actions were undertaken to preserve those habitats, with differing results. We examined tendencies of vegetation during recent 20-30 years, basing on floristical data. In the areas, where water regime has been disrupted, like Natural Landscape Complex "Olszyna" a significant decline of plants rare in the scale of Warsaw is being noticed. Habitats not disturbed by human interference like "Zakole Wawerskie" do not suffer significant changes, even an increase of rare plants was marked. Presence of water dependent ecosystems is also correlated with population density. In the areas of highest population density these habitats occur seldom, are of a small size and have simplified border zones. The only areas within Warsaw borders where water dependent ecosystems maintained are the urban parks. In the last decades a progressive decline of wetlands is being noticed, which was also confirmed in this study. The only real chance for further preservation of this areas is to create biodiversity hotspots and good recreation infrastructure.

Open access

Piotr Sikorski, Karolina Jackowiak and Iwona Szumacher

Abstract

The goal of this paper is to present interdisciplinary environmental studies in urban park. Simple measures are proposed here for evaluating the status of vegetation and its habitat. When systematically applied, these measures could be a basis for sustainable management of the park greenery. Studies performed in Skaryszewski Park in Warsaw are as an example. Studies confirmed the assumption that simple and relatively cheap field and laboratory methods could be a good basis for recognising the status of plant habitats in parks.

Open access

Piotr Żarczyński, Andrzej Strugała, Aleksander Sobolewski and Czesław Sikorski

Streszczenie

Spowolnienie gospodarcze w Europie i świecie w szczególny sposób oddziałuje na tradycyjne branże przemysłu. Polskie koksownie od kilku lat systematycznie modernizowały swój potencjał produkcyjny i nadal prowadzą i planują działalność rozwojową. W obecnych warunkach strategia koksowni powinna być ukierunkowana z jednej strony na unikanie zbędnego ryzyka, a więc wdrażanie znanych technologii. Jednocześnie inwestycje w nowe i innowacyjne technologie jako niosące w sobie dużą zmienność powinny być postrzegane jako szansa. W warunkach znacznej niepewności niezbędna jest jednak zmiana podejścia do oceny przedsięwzięć inwestycyjnych. Tradycyjny rachunek dyskontowy ze względu na swój statyczny charakter - nie uwzględniający zmienności i opcji tkwiących w projektach oraz wielości momentów decyzyjnych - może okazać się już niewystarczający. Pomocnym narzędziem dla decydentów jest w takich warunkach rachunek opcji rzeczowych. W artykule przedstawiono dotychczasowe wyniki projektu badawczo-rozwojowego polegającego na wdrożeniu operacji podsuszania wsadu realizowanego przez Koksownię Zdzieszowice i ICHPW w Zabrzu. Omówiono uzyskane wyniki i związane z nimi ryzyka. Przedstawiono dalsze zamierzenia rozwoju tego projektu, zakładające budowę przemysłowej instalacji badawczej do badania wpływu podsuszania na proces koksowania. Scharakteryzowano przesłanki zastosowania rachunku opcji rzeczowych do oceny przedsięwzięć inwestycyjnych charakteryzujących się dużąniepewnościąrezultatów. Przedstawiono genezę i podział opcji rzeczowych oraz warunki ich stosowania w porównaniu do tradycyjnych dyskontowych metod oceny projektów. Omówiono genezę i parametry charakterystyczne opcji rzeczowych. W następnej części dokonano wyceny przedsięwzięcia badawczo-rozwojowego wdrożenia operacji podsuszania wsadu dla zespołu dwóch baterii koksowniczych metodą NPV oraz metodą opcji rzeczowych. Do oceny wartości opcji rzeczowej tego projektu, będącego klasyczną europejską opcją kupna, wykorzystano równanie Blacka-Scholesa. Dokonano porównania uzyskanych wyników i ustalono wartość elastyczności tkwiącą w analizowanym projekcie badawczo-rozwojowym.

Open access

Krystyna Pohorecka, Teresa Szczęsna, Monika Witek, Artur Miszczak and Piotr Sikorski

Abstract

The present studies are the second part of the research project dedicated to finding the causes for increased winter mortality of honey bee colonies. The aim of this task was to investigate incidents of overwintered colonies′ death with regard to the potential interrelation to the exposure to pesticides. The samples of winter stores of bee bread and sugar food (honey or syrup processed by bees), beeswax and bees collected from apiaries with low and high rates of winter colony mortality were searched for acaricides used to control V. destructor and plant protection pesticides. The presence of acaricides used in apiculture has been detected in the 51% beeswax samples. The most abundant acaricide was tau-fluvalinate. The stores of bee bread and sugar food had a similar frequency of plant protection pesticide occurrence, ranging between 50-60%, but the number of active substances and their concentrations were substantially lower in sugar food samples. The most prevalent pesticides in pollen were fungicides (carbendazim and boscalid) and insecticides (acetamiprid and thiacloprid). Only a few pesticides were found in the several dead honey bees. The level of pesticide contamination (frequency, concentration, toxicity) of hive products and bees originating from apiaries with both a high and low winter colony survival rates, was similar, which created a similar extent of risk. Although the multiple varroacides and pesticides were present in the hive environment we not found unequivocal links between their residues and high winter colony mortality.

Open access

Krystyna Pohorecka, Piotr Skubida, Piotr Semkiw, Artur Miszczak, Dariusz Teper, Piotr Sikorski, Katarzyna Zagibajło, Marta Skubida, Dagmara Zdańska and Andrzej Bober

Abstract

The effects to honeybee colonies (Apis mellifera L.) during and after exposure to flowering maize (Zea mays L.), grown from seeds coated with clothianidin and imidacloprid was assessed in field-realistic conditions. The experimental maize crops were adjacent to the other flowering agriculture plants. Honey bee colonies were placed in three differently protected maize fields throughout the blooming period, and thereafter they were transferred to a stationary apiary. Samples of pollen loads, bee bread, and adult bees were collected and analyzed for neonicotinoid residues. To ensure high specificity and sensitivity of detection of the analyzed pesticides, a modified QuEChERS extraction method and liquid chromatography coupled with tandem mass spectrometry were used. Clothianidin was detected only in the samples of pollen loads. Their residue levels ranged from 10.0 to 41.0 ng/g (average 27.0 ng/g). Imidacloprid was found in no investigated sample. No negative effects of neonicotinoid seed-treated maize on the development and long-term survival of honey bee colonies were observed. The low proportion of Zea mays pollen in total bee-collected pollen during the maize flowering period was noted. The findings suggest that maize plants are less attractive forage for honey bees than phacelia (Phacelia tanacetifolia Benth.), buckwheat (Fagopyrum Mill.), white clover (Trifolium repens L.), goldenrod (Solidago L.), and vegetation from Brassicaceae family.

The results indicate a possibility of reducing the risk of bees being exposed to the toxic effect of insecticidal dusts dispersed during maize sowing by seeding, in the areas surrounding maize crops, plants that bloom later in the year.

Open access

Krystyna Pohorecka, Piotr Skubida, Artur Miszczak, Piotr Semkiw, Piotr Sikorski, Katarzyna Zagibajło, Dariusz Teper, Zbigniew Kołtowski, Marta Skubida, Dagmara Zdańska and Andrzej Bober

Abstract

The risk exposure of bee colonies to the toxicity of systemic neonicotinoid insecticides was assessed. Various methods of chemical prevention of commercial winter and spring oilseed rape crops in field-realistic conditions were taken into account in the assessment. Pesticides were applied in accordance with the actual agricultural practice. Commercial crop protection products with thiamethoxam, clothianidin or imidacloprid were used as seed treatment. Formulations containing acetamiprid or thiacloprid were used for spraying. Fifteen healthy bee colonies were placed in close proximity to each of the oilseed rape fields throughout the blooming period. During florescence, the samples of nectar (directly from flowers and nectar flow from combs) and pollen loads were collected repeatedly. Samples of honey, bee bread and adult bees were taken one week after the end of plants flowering. To ensure high specificity and sensitivity of analysed pestcicides modified QuEChERS extraction method and liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) was used. The five of neonicotinoid insecticides (imidacloprid, clothianidin, thiametoxam, acetamiprid and thiacloprid) were analyzed in multi-residue method with 0.1 - 10 ng/g limits of detection. Palynological analysis was done to determine the botanical origin of the nectar, honey and pollen. Development of bee colonies (brood area, worker biomass, colony health) was assessed every 3 weeks until the end of the beekeeping season. The amount of pollen collected by bees per hive, bee bread area and rape honey yield was also measured. The long-term effects of insecticides on bees were estimated using the same methods in April of the following year.

All the neonicotinoid insecticides applied to control oilseed rape pests were present in the samples of nectar and pollen. Their residue levels were lower than the acute oral and contact LD50 values. Among five examined neonicotinoids, the most frequently detected were: thiamethoxam, thiacloprid and acetamiprid. These substances were present in 65, 64, and 51% of the nectar samples and in 37, 62, and 45% of the pollen samples, respectively. The highest level of residues were noted after the thiamethoxam seed treatment; on average, 4.2 and 3.8 ng/g in the nectar and pollen samples. In the nectar and pollen samples from winter rape fields, lower levels of neonicotinoid residues were found in comparison to spring rape samples. The contaminations of neonicotinoids applied as seed dressing in nectar samples were significantly higher in comparison to the pollen samples. No negative effects of neonicotinoids on the bee mortality, brood development, strength, and honey yield of healthy bee colonies were found throughout the study period. However, the risk exposure of bee colonies on adverse impact of pesticide residues is high in areas of intensively cultivated oilseed rape.