Fractionation of soil phosphorus in a long-term phosphate fertilization

The changes in inorganic and organic phosphorus (P) fractions of soil resulting from long-term fertilization (40 years) were investigated. In order to improve understanding of the sink and sources of phosphorus, P-fractions were extracted from soil samples of 0-30 and 30-60 cm depth with different amounts of monoammonium-phosphate (MAP) and then determined. Stagnosol was the type of the studied soil. Phosphate fertilizer was applied in 26, 39 and 52 kgP/ha amounts during the period of 40 years. Samples were subjected to sequential extraction according to the modified Chang and Jackson method and BCR (Community Bureau of Reference) sequential extraction procedure in order to extract different forms of phosphorus. The Certified Reference material CRM 684 (River Sediment Extractable Phosphorus) was used to provide accuracy of the instrument and both used methods. Furthermore, the association of phosphorus with substrates was provided by comparison of the results of sequential methods of phosphorus species with the sequential extraction of metals (Fe, Al, Mn and Ca). Results of continuous fertilization during 40 years indicated the increase of all the phosphorus forms in the soil except of phosphorus bound to calcium and organic phosphorus. Application of higher amounts of P-fertilizer resulted in dominance of Al-P fraction in studied soil which indicated that this fraction was the most responsible for the migration of phosphorus along the soil profile

Mineral Composition of Red Clover under Rhizobium Inoculation and Lime Application in Acid Soil

In the present study the effects of Rhizobium inoculation and lime application on the mineral composition (N, P, K, Ca, Mg, Fe, Mn, Cu, Zn, B) of red clover (Trifolium pratense L.), in very acid soil were evaluated. Inoculation with Rhizobium leguminosarum bv. trifolii significantly increased shoot dry weight (SDW) of red clover plants (three times greater), as well as N, Mg, Fe, Mn and Cu contents in plants compared to the control. Application of lime and Rhizobium together, depending on the lime rate (3, 6 or 9 t ha-1 of lime) and the cut, increased SDW significantly, but decreased the contents of N, P, K, Mg, Mn, Zn and B in plants. Regardless of the changes, in all treatments in both cuts, contents of N, K, Ca, Mg, Mn and Zn in plants were among sufficiency levels (Mg content was elevated in the second cut), while Fe content was mainly high, as well as Cu (in the second cut). Contents of P and B in plants were somewhat lower than sufficiency levels, but above critical level. Therefore, red clover can be grown with satisfactory yield and mineral composition in acid soil with Rhizobium inoculation only, but the application of P and B fertilization is desirable

Primena GIS u proceni topografskih i hemijskih parametara pogodnosti za uzgoj vinove loze

In this paper, unique vineyard plots are selected, according to suitability of topographic and chemical parameters in municipality of Krupanj. Separation of vineyard plots was performed using GIS, which enables processing, analysis and presentation of spatial data. Benefits of GIS tools in the preparation of this work were highlighted during the presentation of topographic factors from DEM and through the use of geostatistics in processing spatial data. By analyzing only the topographic parameters, it was concluded that 0.97 km2 of municipality area has ideal conditions for growing vines, but only 0.0039 km2 according to both topographic and chemical parameters. The applied methodology allows fast and reliable determination of sites that are ideal for growing grapes. This gives a basis to municipal authorities for realistic assessment of significance and conditions, as well as further developments planning.U ovom radu izdvojene su jedinstvene vinogradarske parcele na osnovu povoljnih topografskih i hemijskih parametara plodnosti na području opštine Krupanj. Izdvajanje vinogradarskih parcela izvedeno je primenom GIS (Geografski Informacioni Sistem) tehnologija koje nam pružaju mogućnosti obrade, analize i prezentacije prostornih podataka. Prednosti GIS alata u izradi ovog rada bile su naglašene prilikom izvođenja topografskog faktora iz DEM-a (Digitalni Elevacioni Model) i kroz upotrebu geostatistike u obradi prostornih podataka U radu je utvrđeno da, analizirajući samo topografske parametre, 0.97km2 opštine ima idealne uslove za uzgajanje vinove loze, dok svega 0.0039 km2 opštine poseduje jedinstvene vinogradarske parcela izdvojene po oba kriterijuma: topografski i hemijski parametri. Primenjena metodologija pruža mogućnost brzog i pouzdanog utvrđivanja lokaliteta koji su idealni za uzgajanje vinove loze. Time se opštinskim službama daje osnova za realnu procenu stvarnog značaja, povoljnosti uslova i planiranje daljeg razvoja ove vrste proizvodnje

Macronutrient contents in the leaves and fruits of red raspberry as affected by liming in an extremely acid soil

The study evaluates the effect of liming materials application in combination with NPK fertilizer and borax on macronutrient contents (nitrogen (N), phosphorus (P), potassium (K), calcium (Ca) and magnesium (Mg)), in an extremely acid soil and raspberry leaves and fruits during a two-year period. Liming increased soil pH, N mineral content, P, Ca and Mg soil content, while K content either increased (dolomite and borax application), or decreased (lime application). The N and P contents in raspberry leaves after liming increased significantly, but P content remained below the optimal values. Some treatments with lime caused a decrease in K content in leaves, while dolomite and borax application increased K content. Initially optimal Ca content in leaves increased significantly in the treatments with lime, but decreased after dolomite application. The Mg content in leaves increased after dolomite and borax application, but mainly remained below optimal values. Liming either did not alter or only slightly altered macronutrient contents in raspberry fruits

Contamination, risk, and source apportionment of potentially toxic microelements in river sediments and soil after extreme flooding in the Kolubara River catchment in Western Serbia

Climate change is contributing to an increase in extreme weather events. This results in a higher river flooding risk, causing a series of environmental disturbances, including potential contamination of agricultural soil. In Serbia, the catastrophic floods of 2014 affected six river basins, including the Kolubara River Basin, as one of the larger sub-catchments of the large regional Sava River Basin, which is characterized by large areas under agricultural cultures, various geological substrates, and different types of industrial pollution. The main aim of this study was to establish the sources of potentially toxic elements in soil and flood sediments and the effect of the flood on their concentrations. Field sampling was performed immediately after water had receded from the flooded area in May 2014. In total, 36 soil samples and 28 flood sediment samples were collected. After acid digestion (HNO3), concentrations of the most frequent potentially toxic elements (PTE) in agricultural production (As, Cd, Cr, Cu, Ni, Pb, Zn) and Co which are closely related to the geological characteristics of river catchments, were analyzed. The origin, source, and interrelations of microelements, as well as BACKGROUND: values of the PTE of the river catchment, the pollution index (Pi), enrichment factor (Ef), and geological index (Igeo), were determined, using statistical methods such as Pearson correlations, principal component analysis (PCA), and multiple linear regression (MLRA). The content of the hot acid-extractable forms of the elements, PCA, and MLRA revealed a heavy geological influence on microelement content, especially on Ni, Cr, and Co, while an anthropogenic influence was observed for Cu, Zn, and Cd content. This mixed impact was primarily related to mines and their impact on As and Pb content. The pseudo-total concentrations of all the analyzed elements did not prove to be a danger in the catchment area, except for Cu in some samples, indicating point-source pollution, and Ni, whose pseudo-total content could be a limiting factor in agricultural production. For the Ef, the Ni content in 59% soil and 68% flood sediment samples is classified into influence classes. The similar pseudo-total contents of the elements studied in soil samples and flood sediment and their origin indicate that the long-term soil formation process is subject to periodic flooding in the Kolubara River Basin without any significant changes taking place. This implies that floods are not an endangering factor in terms of the contamination of soil by potentially toxic elements in the explored area

Labile fractions of soil organic carbon in mollisols from different climatic regions

Characterization of Labile Fractions of Soil Organic Carbon in Mollisols from different climatic regions. The research studied the potential mineralization and characterization of labile SOM of different types of Mollisols: Hapludolls, Argiudolls, Calciustolls, and Haplustolls. Labile C fractions distributed oppositely than total SOC and were the greatest in Calciustolls and the lowest in Hapludolls. The amount of soil microbial biomass C (MBC) was significantly higher in dry than in wet regions. The highest amount of light fraction C was in dry-thermic followed by dry-frigid, and the least amount was in wet regions. Dry regions were able to retain a higher level of labile C than the moist regions, due to a slower annual decomposition rate

Liming of anthropogenically acidified soil promotes phosphorus acquisition in the rhizosphere of wheat

We studied the effect of liming and P fertilization of extremely acid soil (accidently acidified by sulfidic mining waste) on P availability and the subsequent adaptive responses of wheat roots. The wheat plants were grown in rhizoboxes allowing precise sampling of rhizosphere and bulk soil for sequential extraction of P fractions and determination of exchangeable Al. Root exudates were collected by pieces of paper for electrophoresis and subjected to HPLC analysis. Expression of organic anions and P-i transporter genes was analyzed by a real-time quantitative PCR. The concomitant application of lime with P fertilization increased the concentrations of plant-available P fractions in both rhizosphere and bulk compartments. The applied soil amendments strongly affected plant growth, biomass partitioning and shoot P accumulation. Liming enhanced root exudation of citrate in P unfertilized plants, while the high malate efflux was maintained until both P deficiency and Al toxicity were eliminated by the amendments. We showed the importance of liming for recovering of P acquisition potential of wheat roots, which can be strongly impaired in acid soils. Our results clearly demonstrated that P-deficient roots not subjected to Al stress in the limed soil can maintain high efflux of malate and even increase efflux of citrate along with the enhanced expression of related anion transporters (TaMATE1 and TaALMT1)

Impact of energy saving cultivations on soil parameters in northern Kazakhstan

Recently the cost of soil processing for agricultural production has been rapidly increasing because of expensiveness of agricultural machinery, energy, and agricultural chemicals. Intensive soil cultivation is costly and adversely affects soil fertility due to accelerated mineralization of soil organic matter. By minimizing mechanical disturbance to the soil, costs can be reduced and the environment enhanced. About half of the global CO2 emissions from the soil come from decomposition of the annual plant litter including agricultural crops. We studied methods of soil tillage that would help stabilize the yield of crops while maintaining soil fertility and saving energy and labour at the same time. Three types of crop cultivation experiments were studied: 1) cultivation intensity (simplified ST, common CT, and intensive IT); 2) tillage depth (shallow S, and deep D subsoil till), and 3) minimum MT, and zero till ZT. The results showed that under ST the soil biological parameters were more favourable than under CT and IT. Shallow subsoil till maintained higher levels of soil nutrients, and reduced CO2 emission compared with the deep subsoil till. The minimum and zero tills positively influenced soil physical and biological properties through improvement in soil aggregate stability and soil enzymatic activity