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1

Determination of kinetic energy of phosphorus in the open trough waters of Lake Starzyc

100%

Konieczny R.

Teka Komisji Motoryzacji i Energetyki Rolnictwa

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2008

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tom 08a

2

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Phosphorus runoff from small agricultural catchments under different land use intensity

100%

Skwierawski A., Sobczynska-Wojcik K., Rafalowska M.

Journal of Elementology

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2008

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tom 13

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nr 4

637-646

The study was carried out in the hydrologic year 2006 and comprised two small agricultural catchments in the Masurian Lakeland. Both catchments possessed very large water retention potential (presence of buffer zones and surface waters in the catchments) but they differed in the intensity of agricultural production. The study has demonstrated that the concentration of phosphorus in the surface waters flowing from the catchments ranged from 0.12 to 0.43 mg⋅dm-3. The catchments were characterised by low indices of water overland flow (0.32-1.67 dm3⋅s-1⋅km-2), which was a decisive factor shaping the runoff of phosphorus (from 0.013 to 0.060 kg⋅ha-1⋅year-1. A subcatchment dewatered by a pipe drain system, which was used for comparison, had a water flow of 3.54 dm3⋅s-1⋅km-2 and exported much more phosphorus with its surface waters (0.39 kg⋅ha-1⋅year-1). The results obtained during our study emphasise an important role played by small landscape water retention elements in both catchments and the efficiency of buffer zones at a contact of water bodies and fields in reducing the runoff of biogenic substances, especially when agricultural production carried out on a given catchment is intensive.

3

Transport of biogenic substances in watercourses of Coastal Landscape Park

100%

Krajewska Z., Fac-Beneda J.

Journal of Elementology

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2016

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tom 21

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nr 2

Eutrophication of the Baltic Sea is a serious problem, and as such it is frequently raised in relevant literature, where potamic supply of nutrients is implicated as one of the causes. Coastal waters like the Puck Lagoon, an area protected within the Natura 2000 network, as well as watercourses in adjacent Coastal Landscape Park, are particularly vulnerable to such degradation. Hence, the aim of our study, which was to determine the volume and fluctuations of transported total nitrogen and phosphorus. Another objective was to try and relate these changes to the transport of nutrients and runoff in streams flowing through Coastal Landscape Park into the Puck Lagoon (the Płutnica, Potok Błądzikowski, Gizdepka, Reda, Zagórska Struga) and into the Baltic Sea (the Piaśnica, Karwianka, Czarna Wda). This research drew on field investigations and laboratory assays performed in the hydrological year of 2009, and had been designed accordingly, including measurements of the flow rate in the selected watercourses and water sampling for further chemical analyses, including determinations of total nitrogen and total phosphorus. In brief, the highest average annual flow rate and load of total nitrogen and total phosphorus were found in the Reda and Piaśnica. The largest load variation, of both nitrogen and phosphorus, occurred in the Zagórska Struga. In most of the watercourses, the load of biogenic substances was strongly correlated with the flow, but the actual power of correlation depended on a stream and biogenes. The strongest statistical relationships for both tested substances (r > 0.8) occurred in the Potok Błądzikowski, Reda, Zagórska Struga and Czarna Wda. The Płutnica was an exception in that there were no statistically significant relationships between the water flow and the load of nutrients. However, the low value of the relationship determined suggests that we should view that series with some caution.

4

First report of Pythium aphanidermatum infecting tomato in Egypt and its control using biogenic silver nanoparticles

100%

Elshahawy I., Abouelnasr H. M., Lashin S. M., Darwesh O. M.

Journal of Plant Protection Research

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2018

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tom 58

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nr 2

In August 2016, tomato plants grown during a hot, wet summer with heavy soil flooding, displaying symptoms of wilting, dead plant, root rot with crown and stem rot, at Beni Suef and Fayoum governorates were examined. A number of 16 fungal isolates were isolated from tomato plants displaying the above symptoms. These isolates were classified as belonging to six species, namely: Alternaria solani, Chaetomium globosum, Fusarium solani, Fusarium oxysporum, Pythium spp. and Rhizoctonia solani. Isolates of Pythium spp. were prevalent and were found to be more pathogenic than the other fungal isolates. This species causes damping-off, root rot, sudden death, stem rot and fruit rot. The pathogen was identified as Pythium aphanidermatum based on morphological, cultural, and molecular characteristics. Biogenic silver nanoparticles (AgNPs) were produced using the F. oxysporum strain and characterized by transmission electron microscopy (TEM). The size of these spherical particles ranged from 10 to 30 nm. In vitro, biogenic AgNPs showed antifungal activity against P. aphanidermatum. In greenhouse and field experiments, AgNPs treatment significantly reduced the incidence of dead tomato plants due to root rot caused by P. aphanidermatum compared to the control. All of the investigated treatments were effective and the treatment of root dipping plus soil drenching was the most effective. To the best of our knowledge, this study describes P. aphanidermatum on tomato in Egypt for the first time. Also, biogenic AgNPs could be used for controlling root rot disease caused by this pathogen.

5

Seasonal variability of mineral nitrogen in groundwater of hydrogenic soils

100%

Szymczak S., Pawluczuk J., Stepien A.

Journal of Elementology

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2010

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tom 15

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nr 4

713-723

Agricultural use of land on hydrogenic soils is associated with lowering the groundwater level, which intensifies the processes of organic matter mineralisation and, in effect, releases large amounts of mineral nitrogen. The aim of the study was to determine the seasonal variability of the concentrations of nitrogen mineral compounds (N-NO2, N-NO3 and N-NH4) in groundwater under extensively managed peat-muck soils, situated in Wrocikowo in the Olsztyn Lakeland and in the Dymerskie Meadows in the Mrągowo Lakeland. Peat-muck soil, found at the study sites, had varied physical properties. The highest content of mineral particles (69.3%) in the muck layer was found in soil marked as MtI 120gy under turf-covered wasteland, and in the peat layer (51.5%) – in soil marked as MtII 60gy under extensively managed meadow. Groundwater taken from piezometers installed in hydrogenic soils was used as the study material. Water for chemical determinations was taken during four seasons: spring – in May, summer – in August, autumn – in November and winter – in January. The concentration of mineral forms of nitrogen in groundwater of peat-muck soil was found to depend on its type, the depth where the groundwater was found and the type of soil use. The highest concentration of mineral nitrogen was found in summer (1.62 mg dm–3 on average), and the lowest (1.11 mg dm–3 on average) was found in winter. The concentration of mineral nitrogen in groundwater of extensively managed peat-muck soil ranged from 0.81 to 2.27 mg dm–3 and was found to be dependent on the type of soil rather than its use. Lowering the level of groundwater in peat-muck soil increases the concentration of mineral forms of nitrogen, especially N-NH4. Ammonium nitrogen was the dominant form of nitrogen in the groundwater of peat-muck soil (MtII 60gy and MtI 120gy) of non-managed and extensively managed meadows, whereas nitrate nitrogen was the dominant form of the element in the MtIc 35gy soil under the meadow and the MtII bb under the pasture.

6

The effects of abiotic conditions on release of biogenic substances from bottom sediments

80%

Sobczynski T.

Oceanological and Hydrobiological Studies

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2009

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tom 38

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nr 1

45-53

7

The role of lakes in inflow of water and biogenic substances in the Polish part of the Southern Baltic Sea

80%

Janczak J., Niemirycz E.

Oceanological and Hydrobiological Studies

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2011

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tom 40

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nr 4

8

The chemistry of water and bottom sediments in relation to zooplankton biocenosis in small agricultural ponds

80%

Joniak T., Kuczynska-Kippen N.

Oceanological and Hydrobiological Studies

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2010

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tom 39

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nr 2

9

Ecological status of shallow Lake Gorbacz (NE Poland) in its final stage before drying up

80%

Zielinski P., Ejsmont-Karabin J., Grabowska M., Karpowicz M.

Oceanological and Hydrobiological Studies

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2011

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tom 40

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nr 2

10

Biogenic silver nanoparticles from Trichodesma indicum aqueous leaf extract against Mythimna separata and evaluation of its larvicidal efficacy

80%

Buhroo A. A., Nisa G., Asrafuzzaman S., Prasad R., Rasheed R., Bhattacharyya A.

Journal of Plant Protection Research

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2017

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tom 57

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nr 2

Th e present exploration is focused on the bio-fabrication of silver nanoparticles (Ag NPs) using Trichodesma indicum aqueous leaf extract as a reducing agent. Th e synthesized Ag NPs were productively characterized by UV-vis spectroscopy, XRD, and TEM studies. Th e photosynthesis of Ag NPs was done at room temperature for 24 h and at 60°C. Th e green synthesis of spherical-shaped Ag NPs bio-fabricated from T. indicum with a face centred cubic structure showed average particle sizes of 20–50 nm, which is inconsistent with the particle size calculated by the XRD Scherer equation and TEM analysis. We further explored the larvicidal effi cacy of biosynthesized Ag NPs with leaf extracts of T. indicum against Mythimna separata. Th e results showed that Ag NPs (20–50 nm) of T. indicum possess good larvicidal activity against M. separata with an LC50 of 500 ppm. Th us, we can advocate that Ag NPs of 20–50 nm size extracted from T. indicum may be considered in the pest management programme of M. separata in future.

11

Preliminary characterization of the trophic state of Maly Kopik Lake near Olsztyn and its drainage basin as a supplier of biogenic substances

70%

Grochowska J., Tandyrak R.

Journal of Elementology

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2008

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tom 13

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nr 1

The study was carried out on a small (7.8 ha) and shallow (9.0 m) lake Mały Kopik, situated 9 km on south western from Olsztyn, drainage basin of Giłwa and Pasłęka rivers. The catchment area of the lake is 194.7 ha. Forests cover the most of the drainage basin area (64.2%), agriculture land comprises 28.7% (21% grass land and 7.7% arable land) and urban land - 7.1%. Lake Mały Kopik is not susceptible to degradation (III category), and drainage basin having a great potential for supplying matter to the reservoir, was included in basin category 4. The lake with its drainage basin belong to the 4th type of lake-drainage basin ecosystems. In such a system the natural eutrophication of the lake is expected to proceed at a fast rate. As evidenced in the study, lake Mały Kopik is highly eutrophic reservoir. The lake waters were characterized by a high content of nutrients, up to 0.673 mg P·dm-3 and 10.61 mg N·dm-3. The high fertility of the lake was exhibited also by the values of BOD5 reaching 7.5 mg O2·dm-3, chlorophyll a content - 50 µg·m-3, and low water transparency - 2 m.

Ograniczanie wyników

Determination of kinetic energy of phosphorus in the open trough waters of Lake Starzyc

Phosphorus runoff from small agricultural catchments under different land use intensity

Transport of biogenic substances in watercourses of Coastal Landscape Park

First report of Pythium aphanidermatum infecting tomato in Egypt and its control using biogenic silver nanoparticles

Seasonal variability of mineral nitrogen in groundwater of hydrogenic soils

The effects of abiotic conditions on release of biogenic substances from bottom sediments

The role of lakes in inflow of water and biogenic substances in the Polish part of the Southern Baltic Sea

The chemistry of water and bottom sediments in relation to zooplankton biocenosis in small agricultural ponds

Ecological status of shallow Lake Gorbacz (NE Poland) in its final stage before drying up

Biogenic silver nanoparticles from Trichodesma indicum aqueous leaf extract against Mythimna separata and evaluation of its larvicidal efficacy

Preliminary characterization of the trophic state of Maly Kopik Lake near Olsztyn and its drainage basin as a supplier of biogenic substances