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Cornelia Lupu, Cătălina Druţu, Lorena-Diana Popa and Margareta Naie

, Borlan Zenovia, 1980 - Ghid pentru alcătuirea planurilor de fertilizare (Guide for making fertilizer plans). Edit. Ceres, Bucureşti. Lupu Cornelia, 2007 - Influenţa îngrăşămintelor cu azot şi fosfor asupra producţiei de grâu la S.C.D.A. Secuieni, Neamţ - 45 de ani de activitate ştiinţifică (The influence of nitrogen and phosphorus fertilizers on wheat crop production at A.R.D.S. Secuieni, Neamţ county - 45 years of scientific activity). Edit. Ion Ionescu de la Brad, Iaşi. Mihăilă V., Burlacu Gh., Hera Cristian, 1996 - Rezultate obţinute

Open access

Jolanta Treinyte, Violeta Grazuleviciene and Jolita Ostrauskaite

Abstract

Composites consisting of polyvinyl alcohol, nitrogen- and phosphorus-containing waste materials were prepared and studied as materials for encapsulation of mineral fertilizers By-products of biodiesel production (rapeseed cake, crude glycerol), horn meal (waste product of haberdashery) and phosphogypsum (by-product of the production of phosphorus fertilizers) were used as the fillers of the composites. The films of the composites with the different amounts of nitrogen and phosphorus were prepared using different fillers or their mixtures. Mechanical, properties of the films, hygroscopicity, solubility in water were studied. The composites developed were used for the encapsulation of mineral fertilizers. It was established that encapsulation resulted in the increase of the time of release of the fertilizers. The developed slow-release fertilizers represent a combination of inorganic and organic compounds. The organic part consists of nitrogen- and phosphorus containing horn meal and rapeseed cake. Since assimilation of organic substances is considerably longer, nitrogen and phosphorus of these components will be available for plants much later than inorganic nitrogen and phosphorus. Thus the composite film will not only decrease the rate of desorption of the components from the granules of the fertilizers but will also prolong the impact of the fertilizers on the plants.

Open access

C. Ailincăi, G. Jităreanu, D. Bucur and Despina Ailincăi

ABSTRACT

- The investigations conducted during 2005-2010 at the Podu- Iloaiei Agricultural Research Station, Iaşi county, have studied the influence of different mineral fertilizers rates on wheat and sunflower yield and soil agrochemical characteristics. In bean-wheat-maizesunflower- wheat crop rotation, applying mineral fertilizers resulted in getting mean yield increases, which varied according to rates, between 94 and 180% (1631- 3129 kg/ha) in wheat and between 38 and 101% (773-2063 kg/ha) in sunflower. The mean yield increases, obtained for each kg of a.i. of applied fertilizer, were comprised between 11.2 and 13.6 kg grains (N80P40 - N160P80) in wheat and between 9.2 and 9.7 kg grains (N40P40 - N120P80) in sunflower. In the soils from the Moldavian Plateau, which are poor in organic matter and nutrients, the proper use of different rotations and fertilizer doses may replace a part of high technological consumption, determined the improvement in the content of organic matter from soil and ensured better conditions for the capitalization of nitrogen fertilizers. On the Cambic Chernozem from the Moldavian Plateau, a good supply with mobile phosphorus in wheat and sunflower crops (37-72 mg/kg) was done in case of the annual application of a rate of N120P80, while a very good supply (72-91 mg/kg) was achieved at the rate of N140P100. After 44 years of experiences, in five year crop rotation, fertilization of sunflower, wheat and maize crops with high rates of mineral fertilizers (N160P80), resulted increased soil organic carbon content by 22, 7% (3.5 g C / kg soil), compared to the unfertilized control.

Open access

Despina Ailincăi and C. Ailincăi

Abstract

The paper presented the results of investigations concerning the influence of long-term fertilization (43 years) on some chemical characteristics of soil from the Moldavian Plateau, of wheat-maize rotation. The studies were performed on a typical cambic chernozem soil, prevailing in the Moldavian Plateau, and followed the dosing of fertilizers which ensures an efficient production increases and determines maintain or increase soil organic carbon content. Soil that has been placed experiences-clay loam, neutral to slightly acid reaction and a medium nutrient supply. On lands from the Moldavian Plateau, maintaining a good supply in mobile phosphorus for field crops (37-72 mg/kg) was done in case of the annual application of a rate of N100P100, and a very good supply in mobile phosphorus (69-78) and mobile potassium (over 200 mg/kg) was found at a rate of N100P100+60 t/ha manure. In wheat-maize rotation, applying a rate of N100P100 , for 43 years, has determined the pH decrease until the limit of moderately acid interval (5.1-5.8) and was maintained within the weakly acid interval (5.9-6.8) in case of the annual application of a rate of N50P50 + 60 t/ha manure. Soil organic carbon content, in wheat - maize rotation, decreased after 43 years of experiences from 19.8 to 16.3 g/kg in unfertilized variant and until 18.1 g/kg in case of the annual application of a rate of N100P100. In wheat - maize rotation, the significant increase in organic carbon content from soil has been registered at higher than N50P50 + 40 t/ha manure and at N100P100 + 60 t/ha manure. The determinations of mean annual amounts of nitrogen exported from soil by wheat (grains + straw) have shown that in wheat crop, its values varied according to fertilizers system, between 71.5 and 128.4 kg/ha. In maize crop, of the mean annual amounts of nitrogen exported from soil varied according to applied fertilizers, between 64.6 and 178.9 kg/ha.

Open access

Barbara Sapek

Abstract

Sorption capacity and the energy of phosphorus adsorption on muck and peat deposits were studied in peat- -muck soil profile from a lowland peatland in the Kuwasy object. Soils of the area are characterised by a laminar structure which results in variable sorption properties of peat deposits of different origin, degree of humification (decomposition - R) and transformation of organic matter of upper muck layers (degree of mucking - Z). There was a relationship between the maximum phosphorus adsorption calculated from the Langmuir isotherm (b) and adsorption energy (k) and the type and degree of humification of peat and transformation of muck mass. Muck deposits of the maximum sorption capacity similar to that of peat deposits bind phosphorus less intensively than peats. One may expect that different sorption capacity and the strength of phosphorus binding will effect in different migration of inorganic and organic P compounds in soil profile and their transfer to ground waters.

Open access

Jerzy Barszczewski and Edmund Kaca

Abstract

Ponds play various functions both productive and non-productive. It was demonstrated in the paper that ponds retain water and during heavy rainfalls they act as a flood control measure. Self-purification of water takes place along the pond. Statistically significant reduction of nitrate-N, phosphate-P and calcium concentrations was found in pond water. From 102±24 to as much as 360±53 kg nitrate-N per ha of fishpond is retained during fish growth. Phosphorus may not be retained in fishpond; if it is then the amounts of stored P are small (from 1 to 7 kg·ha-1 on average). Slightly more potassium may remain in the pond. After the period of fish growth and draining the pond, only part of stored load of nutrients reaches the recipient water body. From 200 to 400 kg N-NO3 and up to 2300 kg Ca per ha does not flow out of the pond. The outflow of ammonium-N, phosphorus and potassium may, however, increase or decrease

Open access

Angela Potasznik, Sławomir Szymczyk, Marcin Sidoruk and Ilona J. Świtajska

manured grassland of different soil P status at two rainfall intensities. Agriculture, Ecosystems and Environment. Vol. 153 p. 65-74. KIM M., KWON S., JUNG G., KIM M., LEE S. 2011. Phosphorus losses from agricultural soils to surface water in a small agricultural watershed. Biosystems Engineering. Vol. 109 p. 10-14. KOC J., SKWIERAWSKI A. 2003. Fosfor w wodach obszarów wiejskich, skutki i zapobieganie [Phosphorus in waters in rural areas, consequences and prevention]. Journal of Elementology. Vol. 8(3). Suppl. p. 129

Open access

Józef Koc, Szymon Kobus and Katarzyna Glińska-Lewczuk

migracje azotanów (V) w ekosystemach wodnych doliny rzecznej na przykładzie Środkowej łyny. Ecol. Chemistry Engrg. S2, 13: 295-304. Koc J., Skwierawski A., 2004. Fosfor w wodach obszarów rolniczych. Zesz. Nauk. AE Wroc., Chemia, 1017: 165-182. Leopold L. B., Wolman M. G., 1960. River meanders. Geol. Soc. Am. Bull., 71: 769-794. Mikulski J. S., 1982. Bilogia wód śródlαdowych. Warszawa, PWN: 465. Miranda L.E, Hargreaves J. A., Raborn S. W., 2001. Predicting and managing

Open access

Victor Cucarella, Gunno Renman, Tomasz Zaleski and Ryszard Mazurek

Recycling of Calcium-Silicate Material After Wastewater Filtration to Agriculture - Soil Condition Impact

Reactive filter materials aimed at phosphorus (P) recovery is a novel method for on-site wastewater treatment. Once the bed filter is no longer effective, the sorbent must be replaced and can then be recycled as a soil amendment to agriculture. This study investigated the short-term effects of such amendments in a field with a wheat crop in order to evaluate the risks and/or potential benefits of this disposal option. The developed product Polonite (manufactured from Opoka) was used as a model filter sorbent in the field trial. Rates corresponding to approximately 6 and 8 tons per hectare were applied. In the short-term, this amending did not affect soil physical and sorption properties. The rate of Polonite used here, as P source for wheat was irrelevant in this kind of soil. The usefulness of this disposal option of exhausted filter material is discussed.

Open access

ZYGMUNT BROGOWSKI and WOJCIECH KWASOWSKI

Abstract

Phosphorus content and balance in granulometric fractions of old alluvial soil developed from alluvial deposits od Vistula River in middle Poland was studied. The distribution of phosphorus in particular granulometric fractions of the studied soil showed high quantitative variability vertically in the profile. This resulted from the layered structure of the Vistulian old alluvial formation developed throughout the Holocene. The contribution of grain fractions in phosphorus accumulation increased with a decrease in their diameter, and in certain fractions with a decrease in their quantitative state. Eluviation of phosphorus down the soil profile concerned in particular grain fraction <0.02 mm. Fractions with a larger diameters were not subject to the process. Phosphorus resources calculated from the grain fraction balance in the analysed soil amounted to an average of 1.7 kg·m2 to a depth of 200 cm.