Wyniki wyszukiwania - AGRO

1

Influence of disturbed calcium-phosphate metabolism on the cardiovascular system in patients with chronic renal failure

100%

Rzeszotarski J., Walasek L., Marszalek A.

Journal of Elementology

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2005

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tom 10

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nr 4 Suppl.1

91-92

2

Effect of cadminum chloride on the ovulation and structure of ovary in the inbred KP and CBA mice strains

86%

Godowicz B., Pawlus M.

Folia Histochemica et Cytobiologica

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1985

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tom 23

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nr 4

3

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Seedling recruitment in peat bogs in contrasting hydrologic conditions

86%

Ejankowski W.

Dendrobiology

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2010

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tom 64

The study examined the effect of variation in hydrology on seedling recruitment of shrubs, trees and herbs in peat bogs. The establishment of plants and hydrologic conditions were followed in two peatlands in the Polesie Zachodnie region, Eastern Poland. Meteorological conditions in the study sites ranged from very dry (2006) to very wet (2007) and strongly affected ground water level in the bogs. The emergence of woody species typical for advanced vegetation succession was higher in forest-bog, while the recruitment of typical peat bog plants was higher in open bog. Disturbance in the vegetation positively influencedemergence of typical peat bog species and Betula pubescens, but the effect was only foundin the dry year. Only in Pinus sylvestris did recruitment increase in wet seasons. The results suggested that an increase in the number of woody species in peat bogs may be enhanced during relatively wet seasons and that disturbance in the vegetation cover are not required for seedling recruitment of these plants.

4

Changes in mixed coniferous forest (Querco roboris - Pinetum) as a result of forest economy in the Silesian Upland

86%

Sierka E., Chmura D.

Zeszyty Naukowe Uniwersytetu Zielonogórskiego. Inżynieria Środowiska

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2004

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nr 12[131]

5

Nutrient stoichiometric relations and biogeochemical niche in coexisting plants species: effect of simulated climate change

86%

Penuelas J., Sardans J., Ogaya R., Estiarte M.

Polish Journal of Ecology

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2008

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tom 56

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nr 4

613-622

Here we define a “biogeochemical niche” characterized by the species position in the multivariate space generated by its content not only of macronutrients like N, P or K, but also of micronutrients such as Mo, Mg and Ca, and trace toxic elements such as Pb and As. We then hypothesize that the flexibility of the species “biogeochemical niche” will influence the quality of plant tissue, which may have implications for herbivores, and will affect the species capacity to respond to disturbances and climate change and to adapt to the new climate conditions. We show with a simple multivariate procedure, a principal component analysis (PCA), first, that there is a strong differentiation in the total and relative (stoichiometry) content of the different elements in coexisting plant species, and, second, that there is species-specific plasticity in the response of this elemental composition to experimental climate change. The concentrations of foliar macro and micronutrients, as well as trace elements were measured in several tree species (Quercus ilex L., Phillyrea latifolia L. and Arbutus unedo L. in a Mediterranean broad leaf forest (Prades Mts) and in shrub species (Erica multiflora L., Globularia alypum L. and Dorycnium pentaphyllum Scop.) in a Mediterranean shrubland (Garraf Mts) in control plants and in plants grown in experimental drought and warming plots. The climate conditions were monitored during the period 1999–2005. During this period, in the Prades experiment the drought plots had on average a soil moisture content 9% lower than the control plots, whereas in the Garraf experiment the drought treatment led to a mean reduction in soil moisture of 21% and the warming treatment to 0.9ºC rise. The species with greater changes in biogeochemical niche under increased warming or drought, Arbutus unedo, Erica multiflora and Globularia alypum, were those that were also more affected in growth, photosynthetic capacity and other eco-physiological traits. The species differentiations indicate a strong biogeochemical niche, and that the changes in biogeochemical niche are probably an underlying factor in community structure shifts.

6

Influence of disturbance of honey bee colonies on venom production

86%

Tofilski A.

Pszczelnicze Zeszyty Naukowe

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2000

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tom 44

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nr 2

7

The influence of shoot harvesting on the size and fecundity of Convallaria majalis L.

86%

Kosinski I.

Acta Societatis Botanicorum Poloniae

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2001

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tom 70

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nr 4

8

Abyssal epibenthic megafauna of Clarion-Clipperton area [NE Pacific]: changes in time and space versus anthropogenic environmental disturbance

86%

Radziejewska T., Stoyanova V.

Oceanological Studies

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2000

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tom 29

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nr 2

9

Parasitic infection and disturbances of fertility in humans

86%

Blaszkowska J.

Wiadomości Parazytologiczne

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1998

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tom 44

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nr 4

According to literature of the problem, the disturbances of reproductiveness of human in various parasitic infections are discussed. The mechanisms disturbing the proper functioning of the hosts's reproductive system are not sufficiently understood. They may remain in association not only with a direct or indirect effect of the parasite on the host's endocrinal glands and sexual organs, but also with the host's overall reaction to stress or toxic influences. Parasite's activity may lead to abortion or a significant decrease in fetal body weight. Embryo or fetus may be also damaged in an intrauterine infection.

10

Successional traits of ectomycorrhizal fungi in forest reclamation after surface mining and agricultural disturbances: A review

72%

Kalucka I. L., Jagodzinski A. M.

Dendrobiology

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2016

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tom 76

Ectomycorrhizal (ECM) fungi and their symbiotic associations with forest trees are among major drivers of key ecosystem functions such as carbon and nitrogen cycling, plant nutrient and water uptake from soil, plant-plant facilitation/competition and diversity regulation via common mycorrhizal networks. Through their functional traits and interactions with both abiotic and biotic environment, they also significantly affect the process of open land colonization by trees as well as vegetation succession coupled with soil and ecosystem development. Here we review the role of ECM fungi in the early primary and secondary succession following major anthropogenic disturbances. Based on the examples of mine spoils and post-agricultural lands, we demonstrate key ecosystem services provided by ECM fungi in the processes of forest restoration. We point out ecological mechanisms and adaptations which underpin ECM fungal community successional interactions, particularly life histories, dispersal, spatial structure, host preferences, and sensitivity to environmental filters. We emphasize the need of better understanding the role of ECM fungi in the forest restoration practice as it seems crucial for afforestation success and biodiversity rehabilitation. Thus, ectomycorrhizal traits should be a prime consideration in afforestation and carbon sequestration polices, sustainable forest management and biodiversity conservation practices.

11

Function of heart muscle in people chronically exposed to lead

72%

Kasperczyk S., Przywara-Chowaniec B., Kasperczyk A., Rykaczewska-Czerwinska M., Wodniecki J., Birkner E., Dziwisz M., Krauze-Wielicka M.

Annals of Agricultural and Environmental Medicine

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2005

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tom 12

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nr 2

207-210

Rhythm and conductivity disturbances in heart muscle, change in autonomic system function and raised arterial blood pressure have been described in workers exposed to lead. They may be accompanied by changes in echocardiography test and accordingly we undertook this investigation. The study population included employees of zinc and lead steelworks in the south of Poland that were divided into 2 groups: exposed to lead compounds (n=88) and the reference group - administration workers (n=55) with normal levels of lead concentration in blood (PbB) and zinc protoporphyrin in blood. Left ventricular enddiastolic dimension (LVDd), interventricular septal and posterior wall thickness, right ventricular diastolic, left atrium diameter, aortic diameter and left ventricular ejection fraction (EF) in echocardiograms were performed. Left ventricular mass LVM (g) and left ventricular mass index LVMI (g/m2) was calculated. In the group exposed to lead, EF decreased by 3%, increased LVDd by 6%, and raised LVM by 11% and LVMI by 10%. There was a positive relation between PbB and LVDd (R=0.18) and between PbB and LVM (R=0.14). Decreased EF, enlargement of the left ventricle and raised left ventricle mass in research undertaken, may be a result of raised arterial blood tension.

12

Recovery of macrobenthic assemblages following experimental sand burial

72%

Yanez B., Carballo J. L., Olabarria C., Barron J. J.

Oceanologia

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2008

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tom 50

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nr 3

391-420

Periodic inundation by sand is a very common feature of rocky coasts throughout the world. Even so, there have been few direct observations or experiments to investigate the role of sediments on intertidal rocky shores. We designed a field experiment in Mazatl´an Bay, Mexico, to test the initial impact and subsequent recovery of intertidal macrobenthic assemblages exposed to sand burial at two sites of varying wave exposure. Both sites supported different natural assemblages. Treatment plots for the addition of sediment and control plots (50×50 cm), separated by at least 1.5 m, were randomly placed across the mid-water tidal level. The initial response of the resident macrobenthos and the subsequent recolonization was monitored over a period of 95 days. The main effect of sediment deposition at both sites was mortality and removal of biota due to smothering. The recovery process was rapid and may in part have been the result of the mechanism by which the small, disturbed patches were recolonized. Most of the invertebrates colonized the patches as adults; several seaweeds exhibited vegetative growth as the major mechanism of colonization (e.g., Ulva lactuca Linnaeus, 1753, Amphiroa valonioides Yendo, 1902 and Chaetomorpha antennina (Borgensen) Kutzing, 1849). The rate of recovery varied between the sites, however. Recovery of species numbers proceeded quickly at the sheltered site (day 7), but took 95 days at the exposed site. In contrast, biomass reached control levels by day 45 at the sheltered site, but already by day 15 at the exposed site. By day 95, the assemblages recovered to 83.5% and 81% similarity with the controls at the sheltered and exposed sites respectively. Although differences in wave exposure could be very important in determining the different patterns of recovery at both sites, other biological processes may also play an important part.

13

Endosperm development in seeds of Echium vulgare L. [Boraginaceae] from polluted sites

72%

Biskup A., Izmailow R.

Acta Biologica Cracoviensia. Series Botanica

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2004

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tom 46

39-44

Analysis of endosperm development in plants from contaminated sites (vicinity of the Żelazny Most copper post-flotation reservoir in the Legnica-Głogów Copper District, and the zinc spoil in Katowice-Wełnowiec) showed general similarities in the pattern of endosperm formation in Echium vulgare, but also deviation from typical haustorium structure (~23% frequency), premature degeneration of the haustorium, or degeneration both of the haustorium and endosperm proper (~40%). The most significant irregularities of endosperm development included lower or higher number of nuclei in two cells of the lateral part of the endosperm, lower ploidy level of haustorium nuclei, and cellularization (instead of coenocytic structure) in the lateral cells of the endosperm. Irregularities and degenerative processes presumably resulted from the stress of environment conditions. Because of the nutritive function of those structures, degeneration or atypical structure of the endosperm and its haustorium in some maturing seeds may reduce the fertility of plants colonizing contaminated sites.

14

Effects of hydrological disturbance of different magnitude on riverine habitats and benthic invertebrates

72%

Szczerkowska-Majchrzak E., Grzybkowska M.

Polish Journal of Ecology

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2015

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tom 63

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nr 1

Spates of different magnitude in a four order section of the lowland Drzewiczka River (central Poland) downstream from a dam reservoir and a wild-water slalom canoeing track (abbr. WCT) located just below the dam were studied. For over 20 years daily fluctuations enabling the training of canoeists induced a patchy mosaic of the riverbed, with five dominant habitats: pool, stagnant with emergent plants, submersed macrophyte, bank and riffle. Artificial floods, in September 2000, March 2001 and February 2002, were other flow events of this reach, thus the main aim of this paper is to assess the resistance of macroinvertebrates, measured as the relative lack of loss in density after floods. The three- (September) and five-fold (March) increased discharge in relation to the median affected the riverine environmental variables and caused the entrance into the water column and/or washing away of Ephemeroptera, Trichoptera and Simuliidae. In turn the highest-flow event (February, 16-fold flow increase) induced the instability of all bed patches. Oligochaeta, one of the dominant, inbenthic groups of passive drifters, were dragged along the bottom and then stopped by macrophytes. Meanwhile, chironomids, the second dominant benthic group, showed two kinds of behaviour patterns. Orthocladiinae, organisms prone to drift, were washed away after each flood; consequently the riffle and submersed macrophytes became partly depleted of them. Other midges, inbenthic Chironomini (Chironominae) with worse propensities to drift, were also washed out, except from deeper sediment layers, between the roots of macrophytes and in the bank habitat. Thus the macroinvertebrate assemblages in the Drzewiczka River have adapted to the moderate pulse disturbances, but their response to high flow events depends on the species' traits.

15

The response of wetland plant communities to disturbance: alleviation through symmetric disturbance and facilitation

72%

Xu F., Li M., Zhou D., Liu X., Wang R., Guo W.

Polish Journal of Ecology

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2016

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tom 64

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nr 3

The study pays attention to disturbances in early successional communities of wetland vegetation. We conducted artificial disturbances in a community of Suaeda salsa and Phragmites australis in the Yellow River Delta (China). Eight types of disturbances combining mowing treatments with species treatments were applied. Removal of the standing litters of P. australis or not was defined as mowing treatments, and removal of two species solo or both was defined as species treatments. We sampled 80 quadrats from the treatments plots at different intervals after the disturbance to investigate plant height, abundance, aboveground biomass, the distance between plants to reflect the effect of disturbance on composition, structure, productivity, and function of the plant communities. The strategies of seedling emergence and height growth differed as the canopy changed. Biomass contribution of different species, combined with disturbance intensity, was the main factors that affected the productivity. Homogeneity of disturbance was better for maintaining the functions of plant community in compared with the competitiveness (C), stress-tolerance (S) and ruderality (C-S-R) signatures with the control. Facilitations were reflected by the stagger arrangements in relative growth rates of the two species and in plant-plant interactions calculated by a modified function of competition. Adapting to symmetric disturbance and developing facilitative interactions are important requirements for early succession terrestrial vegetation to establish and stabilize in the seriously saline environments of wetlands.

16

Response of Sphagnum testate amoebae to drainage, subsequent re-wetting and associated changes in the moss carpet – results from a three year mesocosm experiment

72%

Koenig I., Schwendener F., Mulot M., Mitchell E. A. D.

Acta Protozoologica

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2017

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tom 56

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nr 3

17

The relative influence of environmental and human factors on seed plant richness at the province scale in China

72%

Li G., Guo K., Liu C., Liu Y., Song C., Du S.

Polish Journal of Ecology

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2015

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tom 63

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nr 2

Seed plant diversity is under threat due to human over-exploitation and changes in land use. There is a need to identify regions where seed plant diversity is most at risk and establish nature reserves to protect the most important species. This study collected province scale seed plant richness data and corresponding environmental, social and, economic data in China in order to assess the impact of environmental and socio-economic factors on seed plant diversity and to quantify the relative importance of climate, human disturbance, and habitat heterogeneity on the distribution of seed plant diversity. A downscaling model was established to map the spatial distribution of seed plant diversity at a 1-km resolution. The results showed that temperature and precipitation seasonality, potential evapotranspiration, humidity index, altitude range, and gross domestic product were important determinants of seed plant diversity. The relative contribution of temperature seasonality was the most important factor (explaining 29.9–36.2% of the variation). Climate, human disturbance, and habitat heterogeneity explained much of the seed plant richness and density variation (about 69.4–71.9%). A scale-down model explained 72% of seed plant richness variation and showed that the center of seed plant species diversity was mainly located in the southeast area of China in the Qing-Tibet Plateau, Yun-Gui Plateau, Hengduan Mountain region, middle of the Sichuan Basins, Taiwan island, and Hainan island. This study improves our understanding of biodiversity hotspot regions and is a useful tool for biodiversity conservation policy and nature reserve management in China.

18

Effect of metabolic disorders accompanying gastroenteritis on the pancreatic exocrine function in piglets. B. Disturbances of the pancreatic exocrine function in piglets with gastroenteritis

72%

Rychlik A.

Polish Journal of Veterinary Sciences

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2002

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tom 05

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nr 3

19

The effect of neighbouring plant height, disturbance level and gap size on spontaneous recruitment of large-seeded and small-seeded species in Molinietum caeruleae meadows

72%

Kostrakiewicz-Gieralt K.

Polish Journal of Ecology

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2014

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tom 62

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nr 2

The seed size is considered as a key feature, which effects both: colonizing and competitive abilities of species. The disturbance dependent small-seeded taxa are regarded as superior colonists, whereas the large-seeded taxa are considered as best competitors able to survive the competition from adjacent plants and negative effect of litter. The impact of character of standing vegetation, disturbance level and size of gaps on spontaneous recruitment of seedlings of selected light-seeded species (Gentiana pneumonanthe L., Dianthus superbus L.) and heavy-seeded taxa (Serratula tinctoria L., Gladiolus imbricatus L.) were conducted. The investigations were carried out in two areas (A and B). Both of them were consisted of three adjacent patches of Molinietum caeruleae: dominated by small meadow species (labeled MC), prevailed by large-tussocks grasses (labeled GR), and overgrown by willows (labeled SA). In the year 2007, in all patches, ten permanent experimental plots were randomly arranged. In Area A, plots were divided in four square-shaped, neighboring subplots subjected to: no treatment; the removal of litter and moss layers; the removal of litter, bryophytes, and above-ground parts of plants; the removal of litter, moss and the plants, as well as top soil stripping. In the Area B, plots were divided into four subplots measuring from 0.16 m2 to 0.01 m2. In each of them the litter and above-ground part of plant biomass were clipped and removed. The recruitment of seedlings was monitored from 2007 through 2010. In both studied areas, regardless of seed mass, the greatest abundance of seedlings were found in patches MC, and decreased gradually in sites GR and SA. Irrespective of seed size, in subplots where plant cover and litter stayed intact no new genets was noted, moderate appearance of seedlings was observed in subplots without plant necromass, whereas the greatest number of generative progeny was found in subplots without necromass and aboveground parts of plants. The lower abundance of seedlings in subplots without litter, plants and topsoil might have been caused by depletion of seed bank reserves. Moreover, in all patches the number of seedlings of small- and large-seeded taxa increased significantly with augmentation of gap size. In light of performed studies it might be concluded, that the disturbances might play very important role in active protection of studied taxa. The positive impact of disruption diminishes with increasing of plant canopy height. The removal of plant cover and litter contributes to the greatest seedling recruitment but its beneficial effect diminishes with decreasing of opening size.

20

Monitoring of sandy beach meiofaunal assemblages and sediments after the 2004 tsunami in Thailand

72%

Grzelak K., Kotwicki L., Szczucinski W.

Polish Journal of Environmental Studies

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2009

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tom 18

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nr 1

43-51

Three sandy beaches on Phuket and Kho Khao islands, Thailand, were monitored annually to study the short- and long-term impacts of the 2004 tsunami on their meiofauna assemblages and sediment characteristics. The sediment grain size compositions changed significantly within one year after the tsunami (improved sorting and less negatively skewed distributions), but meiofauna assemblages did not. The fast recolonization of the beaches after the tsunami confirmed that meiofauna is highly resilient to ecosystem disturbances. The tsunami was not observed to have a long-term impact on meiofaunal assemblages.

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