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1

Abundance of hydrogenic soils of the Vistula River delta in elements soluble in 0.5 m HCL

100%
Smolczynski S.
Natural Sciences
|
1999
|
tom 02
2
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
Content available

Evaluation of the carbon sequestration capacity of arid mangroves along nutrient availability and salinity gradients along the Red Sea coastline of Saudi Arabia

84%
Shaltout K. H., Ahmed M. T., Alrumman S. A., Ahmed D. A., Eid E. M.
Oceanologia
|
2020
|
tom 62
|
nr 1
3

Biodiversity Versus stability: the biological effect of plant functional traits on ecosystem functioning in grasslands dominated by Leymus chinensis

84%
Zhao N., Shao X., Wang K.
Polish Journal of Ecology
|
2016
|
tom 64
|
nr 3
Although diversity-ecosystem theory predicts that ecosystem functioning is strongly determined by species number, species traits play an important role in regulating ecosystem-level dynamics. We analyze responses of species attributes to diversity level and resource availability, and explore their consequences for ecosystem functioning and ultimately assess the contributions of five traits (vegetative plant height, clonal growth, root depth, cespitose habit and seed mass) to ecosystem functioning defined by spatial stability of community biomass. We found that functional traits disproportionately affected spatial stability. Relationships between species functional traits and spatial stability of community biomass indicated that diversity of vegetative plant height facilitated stability of a nitrogen fertilized undisturbed natural community (NAT), and that of a phosphorus fertilized forb, legume and bunchgrass community (FLB). The clonal growth form was also identified as a stabilizing trigger for a unfertilized undisturbed natural community (NAT), whereas diversity in root depth, cespitose habit and seed mass were related to destabilization of a nitrogen fertilized rhizomatous grass community (RRR). Studies quantifying interactions among plant traits, community structure and ecological functioning will contribute much more to understanding of the effects of the ecological behavior of specific traits on the ecosystem functioning.
4

Recent advances in understanding plant response to sulfur-deficiency stress

84%
Lewandowska M., Sirko A.
Acta Biochimica Polonica
|
2008
|
tom 55
|
nr 3
457-471
Sulfur is an essential macronutrient for all living organisms. Plants are able to assimilate inorganic sulfur and incorporate it into organic compounds, while animals rely entirely on organic sources of sulfur. In the last decades sulfate availability in soils has become the major limiting factor for plant production in many countries due to significant reduction of anthropogenic sulfur emission forced by introducing stringent environmental legislation. The sulfur flux after transferring plants from optimal conditions to sulfur deficiency is regulated on multiple levels including transcription, translation and activity of enzymes needed for sulfate assimilation and synthesis of sulfur-containing metabolites. Most of these regulatory steps are not yet fully characterized. Plant responses to sulfur limitation are complex and can be divided into phases depending on the degree of sulfur shortage. The initial responses are limited to adaptations within sulfur metabolic pathway, while multiple metabolic pathways and developmental process are affected when sulfur shortage becomes more severe. The major aim of this work is a comprehensive review of recent progress in understanding the regulation of plant adaptations to sulfur deficit.
5

Cell surface hydrophobicity of Bacillus spp. as a function of nutrient supply and lipopeptides biosynthesis and its role in adhesion

84%
Czaczyk K., Bialas W., Myszka K.
Polish Journal of Microbiology
|
2008
|
tom 57
|
nr 4
Cell surface hydrophobicity (CSH) is recognised as a important factor in microbial adhesion to solid surfaces. Growth conditions have been found to determine the synthesis of extracellular molecules by microorganisms. It has major consequences in modification of bacterial surface properties and consequently, in bacterial adhesion to solid surfaces. In this paper, CSH properties of Bacillus spp. depending on the nutrient supply and lipopeptide biosynthesis and its role in bacterial adhesion to solid surfaces were investigated. The obtained results indicate that the examined factors (nitrogen and carbon availability) influence the CSH of Bacillus spp. cells. In most variants of the experiments the role of nutrient supply in adhesion process was characteristic for species. The strongest effect was observed for peptone concentration (P<0.001). A decrease of CSH was noticed in optimal nitrogen availability (10 g/l) and it was connected with maximum yield of surfactin biosynthesis. The highest values of CSH of examined Bacillus spp. strains were observed under nitrogen starvation and in excess of carbon source. In these conditions the adhesion to stainless steel surface was more extensive.
6
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Effect of fly ash application on some soil physical properties and microbial activities

67%
Kohli S. J., Goyal D.
Acta Agrophysica
|
2010
|
tom 16
|
nr 2[182]
Electrostatic precipitator (ESP) fly ash obtained from a thermal power plant was mixed with a slightly alkaline soil on w/w basis for use as a potting mixture for poplar nursery and investigated for its influence on microbial activity and physical properties. Application of fly ash as an amendment @ 10% was found to be optimum for bacterial population, soil dehydrogenase activity and microbial biomass. Water holding capacity of fly ash amended soil increased and bulk density decreased as result of fly ash addition as compared to unamended soil. The suitability of fly ash to be used as a soil ameliorant in nursery plantations attains significance from the point of view of eco-friendly disposal of fly ash.
7

Effects of nutrient availability and competition between two grass species Leymus chinensis [Trin.] Tzvel. and Phragmites communis Trin. on the plant performance

67%
Ba L., Xiao N., Xu W., Wang D.
Polish Journal of Ecology
|
2008
|
tom 56
|
nr 3
453-462
Leymus chinensis (Trin.) Tzvel., a perennial grass, is a dominant species from arid to semi-arid steppes in northern China and eastern Mongolia. Phragmites communis Trin. is also a perennial grass, and is distributed widely in the world. In the natural grasslands of northeastern China, both species always co-exist as co-dominating species due to their common characteristics such as propagation both by seeds and vegetative reproduction. Replacement series experiments were used to test the effects of nutrient availability and competitive interaction on the growth performance of two clonal plant species. The experimental treatments included five nutrient levels (3.6, 7.2, 10.8, 14.4 and 18.0 kg organic matter per pot, 20 cm diameter and 15 cm deep) and five species proportions (20:0, 16:4, 10:10, 4:16 and 0:20 for L. chinensis and P. communis, respectively) with twenty tillers in total per pot. Each treatment had 10 replications. Growth characteristics including tiller height, tiller number, plant biomass, rhizome length and bud number of plants in monoculture and mixture culture were recorded and compared to examine the effects of nutrient and competitive interaction on the plant performance. The growth of L. chinensis and P. communis in mixture was influenced by the nutrient availability and competition, which depended on the combination between nutrient level and species proportion. The results implied that the intensity of competition should be lower in nutrient-poor habitats when the co-existing species demanded on the same limiting resource. P. communis benefited from coexisting with L. chinensis, especially under nutrient-rich conditions. The aboveground relative yield (RYabove) expressed in units of tiller height, dry biomass and daughter tiller number was recommended as an effective and simple index to predict the relative competitive ability for clonal plants. It was based on the regression for RY above and RYbelow (the belowground relative yield) against RY (relative yield), measured as yield in mixture divided by that in monoculture.
8

Czy warto wykorzystac liscie burakow cukrowych jako nawoz?

67%
Szczepaniak W., Musolf R.
Agrochemia
|
2003
|
nr 08
26-27
9

Bioaccumulation of PBDE congener 2,2′,4,4′-tetrabromodiphenyl ether by Heterosigma akashiwo in response to different nutrient concentrations

67%
Ge W., Yin X., Chai C., Zhang J.
Oceanological and Hydrobiological Studies
|
2013
|
tom 42
|
nr 2
10
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Content available

Nutrients availability and hydrological conditions of selected wetland ecosystems in the Biebrza river valley

67%
Stelmaszczyk M., Okruszko T., Meire P.
Annals of Warsaw University of Life Sciences - SGGW. Land Reclamation
|
2015
|
tom 47
|
nr 1
Nutrients availability and hydrological conditions of selected wetland ecosystems in the Biebrza river valley. Paper presents results of investigation of hydrological conditions and nutrients limitation and availability for wetland vegetation in selected sites within Biebrza river valley. Analysed sites were overgrown by tall sedge Magnocaricion vegetation (Caricetum gracilis and Caricetum elatae), wet meadow Molinio-Arrhenatheretea vegetation (Molinietum caeruleae), and sedge-moss Scheuchzerio-Caricetea nigrae vegetation (Caricetum lasiocarpae). There were noted a close relationship between vegetation types, hydrological regimes and kind of nutrient limitation. Low productive Molinio-Arrhenatheretea and Scheuchzerio-Caricetea nigrae vegetations fed mainly by groundwater were limited by phosphorus, while highly productive Magnocaricion vegetation, fed by river water, was subjected to nitrogen limitation. We have found big diversifi cation of groundwater and surface water levels within habitats of different vegetation types along the Biebrza river valley. Magnocaricion vegetation present on fl ooded areas is characterized by signifi cant water level fl uctuations and long-lasting inundations. On areas covered by Molinio- -Arrhenatheretea vegetation we noted majority of water levels not exceeding the level of the ground surface. Whereas Scheuchzerio-Caricetea nigrae vegetation, fed by groundwater, is characterized by low variation of groundwater levels.
11

Ground vegetation carbon and its relation to climate and species richness

67%
Solon J., Roo-Zielinska E.
Polish Journal of Ecology
|
2003
|
tom 51
|
nr 4
Ten pine forest sites located along the transect between 50°28′ and 70°09′ N were studied. The purposes of the present paper are: 1) to determine the volume of the organic carbon pool in selected layers of the analysed forest ecosystems (shrubs, herb layer, mosses and lichens, litter, and the humus horizon of the soil); and 2) to elaborate the correlation-based prediction models relating the organic carbon pools in these layers with the selected variables characterising the climate and the species richness of the pine forests. The results indicate a clear horizontal heterogeneity of the ground layer in the pine forests considered. This is reflected, in particular, through the differentiation of the carbon pool in particular places within the ecosystem. There is a distinct geographical variability in the carbon pool among the sites in particular layers, with the average annual and January temperatures having the largest influence on this variability. However, in different cases there are different combinations of the factors describing these relations in the best way. The relations between the carbon pool and the species richness of the sites along the transect show that either the minimal carbon pool occurs at sites of an average species richness, or there is no relation between these variables. The analysis implies that there are two points of the transect at which various characteristics of the system undergo an abrupt shift. The first of them is equivalent to the passage of the annual +1°C isotherm, while the second at approximately 5-6°C. There is the possibility that these regularities occur within the entire range of the pine forests.
12
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
Content available

Effects of grass cover and tillage on temperature of soil in sloping vineyard

67%
Ferrero A., Sudiro L., Nosalewicz A., Lipiec J.
International Agrophysics
|
2004
|
tom 18
|
nr 2
13

The effect of auxins and salicylic acid on chlorophyll and carotenoid contents in Wolffia arrhiza [L.} Wimm. [Lemnaceae] growing on media of various trophicities

67%
Czerpak R., Dobrzyn P., Krotke A., Kicinska E.
Polish Journal of Environmental Studies
|
2002
|
tom 11
|
nr 3
In Wolffia arrhiza {Lemnaceae) growing on municipal tap water (rich in mineral but poor in organic components) and thus being exclusively photoautotrophic, IAA (3-indolilacetic acid) and SA (salicylic acid) strongly stimulated action on the content of chlorophylls a and b and carotenoids (especially β-carotene and lutein + zeaxanthin). On the other hand, the chemical analogues of IAA, i.e. PAA (phenylacetic acid) and NAA (α-naphtylacetic acid), had a generally inhibitory effect on chlorophyll and carotenoid contents. In Wolffia arrhiza growing on raw waste water and a suspension of activated sludge from a sewage treatmentplant (rich in organic substances) characterized by mixotrophism (that is photo- and heterotrophism) PAA had the highest stimulative action on the chlorophyll a and b content, SA negligible, whereas NAA had an inhibitory effect. IAA had a slight stimulative effect on raw sewage but inhibitory on activated sludge. Also, the greatest stimulative effect on carotenoids content was exerted by PAA; SA had a slight stimulative effect while IAA and, to a greater extent NAA had a clearly inhibitory influence.
14

Vertical microzonation of testate amoebae and ciliates in peatbog waters in relation to physical and chemical parameters

59%
Mieczan T.
Polish Journal of Ecology
|
2010
|
tom 58
|
nr 4
Peatbogs have both horizontal and vertical differences in moisture, pH, light and nutrient availability. Micro-distribution of testate amoebae taxa has been observed along the Sphagnum stem but there is no data concerning the vertical micro-distribution of protozoa in water column under the peatbog surface and in the interstitial waters. The research was made in a small (ca 16 ha) peatbog complex in the eastern Poland. Vertical microzonationof testate amoebae and ciliates in relation to physical, chemical and biological parameters (peat porosity, temperature, dissolved oxygen, chlorophyll a, TN, TP, DOC and TOC) in Sphagnum hollows, mud bottom hollows and interstitial waters in peatbog were studied. Samples were taken once a month from April to November 2009 from three layers: free water mass up to 10 cm (FW), bottom water (BW) and interstitial, pore water – IW (water between particles of peat on depth 20–25 cm). During each sampling occasion 3 samples were collected from each site. At each type of micro-habitat and each sampling date water was sampled using a plexiglass core. The water column sampled from the top surface to the bottom was 25 cm high. Interstitial waters were collected from mini-piezometers located into the peat. Temperature, dissolved oxygen, conductivity, chlorophyll a and nutrients contents were always lower in interstitial water than in free and bottom waters. The highest numbers of testate amoebae and ciliates taxa occurred in the bottom water (31 and 13 taxa, respectively) and became much lower in interstitial water (17 and 5 taxa, respectively). The density and biomass of protozoa differed significantly between the studied layers, with the lowest numbers in the interstitial water and the highest in the bottom water. Ordination analysis indicated that chlorophyll a, TOC and TP can strongly regulate the abundance and species composition of protozoa. The RDA ordination showed that the testate amoebae species can be divided into three groups associated with: 1) free water mass, 2) bottom water and 3) interstitial water, while the ciliate species into two groups associated with: 1) interstitial water and 2) free water mass and bottom waters. The free water mass and bottom water were dominated by mixotrophic taxa, whereas the deepest layer showed the increase of the contribution of small, bacterivorous species. In all the examined micro-habitats the highest abundance and biomass of these microorganisms occurred in early spring and late autumn, while the lowest values were recorded in late summer.
15
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Przeplyw cieczy i gazow w osrodku porowatym. Podejscie statystyczne

51%
Usowicz B.
Acta Agrophysica
|
2002
|
tom 63
99-107
16
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
Content available

Wplyw typu gleby i nawadniania na plonowanie i sklad chemiczny brokula

51%
Babik I.
Acta Agrophysica
|
2006
|
tom 07
|
nr 4[135]
793-808
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