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Abstract

Efficient increase in the content of available forms of elements in soil depends not only on their total content introduced to soil material, but also on the technology of its application. Technology consists of techniques and date of application as well as agronomic practices aimed at maintaining proper conditions for element transformations. The method of application of waste elemental sulfur and ground phosphate rock was assessed. Doses of 20 and 40 mg S as well as 40 and 80 mg P·kg−1d.m. were added to medium soil; 30 and 60 mg S as well as 60 and 120 mg P·kg−1d.m. were added to heavy soil. The soil samples were collected on the day of application of materials and after 15, 30, 60 and 90 days. The soil pH value decreased during the incubation. An increase in available sulfur content was observed in both soils after elemental sulfur application; the sulfur content in the medium soil depended on the dose of waste. The soils with the addition of a double dose of ground phosphate rock had the highest content of available phosphorus.

Abstract

The study was conducted in the 2010 - 2012 cropping seasons in a typical ultisols of the tropics. The aim was to assess variability in soil properties as influenced by three land use types namely: oil palm plantation, maize and yam cultivated lands. The study consisted of both field and laboratory studies. The field study was made up of a land use that was carefully surveyed, mapped into 20 × 30 m2 and plotted into 5 homogenous units of 0.25 ha. Soil samples were randomly augered by grid survey at 5 m equidistant points and surface 0-15 cm samples collected using screw auger for laboratory analysis of the particle size distribution and some chemical characteristics of the soils in the different land use types. Variation in properties within land use types was measured by estimating the coefficient of variance. The results of the study showed that particle size distribution varied from sand in the oil palm land use type to sandy loam in the maize and yam land use types. The variant ratio tests were 84.4%, for sand, 0.51% for silt and 27.4% for clay, and were less variable. The soil pH ranged from strongly acid (5.25) to moderate acid (5.65) and less variable (CV% = <15%). The variant ratio test was statistically not significant (10.7%). The organic carbon (35.7%), total nitrogen (34.5%) and available phosphorus (27.2%) variant ratio tests were non-significant and less variable. The exchangeable bases, exchange acidity and ECEC were also non significant and less variable. The results indicated clearly that variability could occur within soil units and therefore called for caution in assessing uniformity of soil properties within soil areas under cultivation

and Productivity of Sites used for Urban Agriculture in Abakaliki, Nigeria. Bioresources Technology , 83: 241–250. [15] Elias, P. and Gbadegesin, A. (2011). Spatial Relationships of Urban Land Use, Soils and Heavy Metal Concentrations in Lagos Mainland Area. Journal of Applied Science and Environmental Manage ment, 15 (2): 391–399. [16] Olsen, S.R., Cole, C.V., Watanable, F.S. and Dean, L.A. (1954). Estimation of Available Phosphorus in Soil by Extraction with Sodium Bicarbonate. USDA Circular , 939: 1–19. [17] Berhanu D (1980). The Physical Criteria and Their

Abstract

This paper presents the results of research examining the soil content of total and available phosphorus (PE-R), taking into consideration the activity of alkaline and acid phosphatases. For this study, three soil profiles were sampled in Arenosols at a distance of 0.8, 2.0 and 2.5 km from a nitrogen fertiliser manufacturer, Anwil S.A. A control profile was taken from the Tuchola Forest. The soils’ reaction ranged from acidic to very acidic. The humus content in the surface horizons of the sampled profiles was average (1.26–2.61%). The lowest PE-R content was found in the profile taken closest (0.8 km – profile I) to the factory. The distribution index (DI) calculated for available phosphorus pointed towards moderate accumulation, whilst at the same time, the availability index (IM) confirmed low availability, especially in profile I. The activity of alkaline and acid phosphatases, which are the enzymes responsible for phosphorus transformation in the soil, varied depending on the distance from the nitrogen works. The inhibition of alkaline phosphomonoesterases and the stimulation of acid esterases, which were both connected to the examined soil reaction, were observed. The activity of phosphatases, as well as total and available phosphorus content, decreased steeply along the soil profiles. Furthermore, a significant correlation between organic carbon and the activity of alkaline and acid phosphatases (r = 0.94, p < 0.05 and r = 0.67, p < 0.05, respectively), as well as between the content of PE-R and the activity of alkaline phosphatase (r = 0.67, p < 0.05) were recorded. The results suggest the need for further research and monitoring of the Arenosols in the forest affected by the nitrogen works.

Tillage in Relation to Distribution of Nutrients and Organic Carbon in the Soil

Changes of total nitrogen, available phosphorus, available potassium and soil organic carbon were observed on gleyic Fluvisols (locality Milhostov) at the following crops: grain maize (2005), spring barley (2006), winter wheat (2007), soya (2008), grain maize (2009). The experiment was realized at three soil tillage technologies: conventional tillage, reduced tillage and no-tillage. Soil samples were collected from three depths (0-0.15 m; 0.15-0.30 m; 0.30-0.45 m). The ratio of soil organic carbon to total nitrogen was also calculated.

Soil tillage affects significantly the content of total nitrogen in soil. The difference between the convetional tillage and soil protective tillages was significant. The balance showed that the content of total nitrogen decreased at reduced tillage by 5.2 rel.%, at no-tillage by 5.1 rel.% and at conventional tillage by 0.7 rel.%.

Similarly, the content of organic matter in the soil was significantly affected by soil tillage. The content of soil organic carbon found at the end of the research period was lower by 4.1 rel.% at reduced tillage, by 4.8 rel.% at no-tillage and by 4.9 rel.% at conventional tillage compared with initial stage. The difference between the convetional tillage and soil protective tillages was significant.

Less significant relationship was found between the soil tillage and the content of available phosphorus. The balance showed that the content of available phosphorus was increased at reduced tillage (by 4.1 rel.%) and was decreased at no-tillage (by 9.5 rel.%) and at conventional tillage (by 3.3 rel.%).

Tillage did not significantly affect the content of available potassium in the soil.

Abstract

The changes of selected chemical parameters were observed in Gleyic Fluvisols. The field experiment was established as a twofactor experiment with four energy crops (Arundo donax L., Miscanthus × giganteus, Elymus elongatus Gaertner, Sida hermafrodita) and two variants of fertilization (nitrogen fertilization in rate 60 kg ha-1, without nitrogen fertilization). Soil samples were taken from the depth of 0 to 0.3 m at the beginning of the experiment in the autumn 2012 and at the end of reference period in the autumn 2015. Land management conversion from market crops to perennial energy crops cultivation has influenced changes of selected soil chemical parameters. The contents of soil organic carbon were affected by cultivated energy crops differently. It was found out that Arundo increased the organic carbon content and Miscanthus, Elymus and Sida decreased its content. At the same time, the same impact of the crops on content of available phosphorus and potassium and soil reaction was found. It was recorded that each cultivated crop decreased the soil reaction and available phosphorus content and increased the content of available potassium.

Abstract

The aim of this study is to differentiate old-field plant communities along the abandonment time and/or environmental gradient in the landscape surrounded villages with established Czech settlers in Romanian Banat area conserving traditional agriculture, and to identify site factors which cause plant diversity of particular vegetation types. Study area: Wider territory centered by the village Sfânta Elena, southern Romania ((44°40’ N; 21°43’ E). Methods: We collected 97 phytosociological relevés covered the same number of old-fields in the area and the following habitat parameters were measured: soil pH, available phosphorus, total carbon and nitrogen, Heat Load Index. Software TURBOVEG / JUICE was used to collect and elaborate the data set of relevés. Old-field vegetation was classified into five basic plant communities using TWINSPAN (all the botanical material includes 291 plant species). For each community, we detected diagnostic species according to their fidelity index. The presence of mowing, grazing or burning was registered for recorded stands. Ecological preferences of each community were examined using one-way analysis of variance (ANOVA). Vegetation-environment relationships were analysed using ordination method – Cannonical correspondence analysis (CCA) in CANOCO for Windows (version 4.5) to find the main variability gradients within the dataset. Scatter plot relationships between variables were constructed. Main results and conclusions: Dependence of number of species (alpha diversity) on the abandoned field’s age exhibits an unimodal shape of this relationship with the maximum peak of species diversity in plant stands aged approximately 13 years. The most importnat ecological factors and/or type of management in the relationship to the old-field plant composition show the following significance order: available phosphorus content in the soil (P), total nitrogen content in the soil (N), presence of burning, length of abandonment (old-field age), carbon/nitrogen ratio in the soil (C/N). Other parameters (grazing, mowing, zero management) do not demonstrate effective impact according to our dataset and seem to be equal to the absence of burning.

Abstract

A field experiment was conducted univariate in 2008-2010 in the Variety Assessment Station in Szczecin - Dąbie. The soil on which the experience was based is made of light loamy sand (pgl). In terms of granulometric composition it includes it into the category of light soils, agricultural suitability complex IV b, good (5). The experiment included, inter alia, waste compost produced with municipal sewage sludge produced by *GWDA and ash from brown coal (waste grate). No normal ranges for heavy metals being specified in the ministerial regulations were used for environmental purposes, which are maximum 20, 500, 750, 300, 1000 and 16 mg per 1 kg dry matter for cadmium, chromium, lead, nickel, copper and mercury, respectively16 were exceeded in the sewage sludge being used to produce the compost. The field experiment design consisted of 6 fertilisation objects. A test plant was Virginia fanpetals (Sida hermaphodrita Rusby). The content of available phosphorus, potassium and magnesium in the soil, being fertilised with municipal SSC with and without an addition of high-calcium BCA, changed after three years. There was an increase in the content of available phosphorus, potassium and magnesium forms, on average by 8.5%, 16.0% and 9.0%, respectively. When analysing the chemical properties of soil before and after this study, it may be stated that respective systems of municipal sewage sludge compost and high-calcium brown coal ash application differently affected most soil richness indices. The best fertilisation effects were obtained in the system with municipal sewage sludge compost being applied at a dose corresponding to 250 kg N ∙ ha-1 as well as with high-calcium brown coal ash at a dose corresponding to 1.5 Mg CaO ∙ ha-1 being introduced into soil in the first year of study and at a dose corresponding to 0.75 Mg CaO ∙ ha-1 in successive years. Fertilisation with municipal sewage sludge compost without and with addition of high-calcium brown coal ash favourably affected the preservation of soil environment stability and improvement of soil chemical composition

Abstract

Soil quality (SQ) dynamics assessment vis-à-vis land use/land cover (LULC) and elevation variations in Ethiopia is desirable as elevation impact on land use is highly pronounced. This study examined SQ indicators dynamics across LULC and elevation variations. For this, surface soil samples (0−20 cm) were collected from the recognized LULC categories of different elevations in Wanka watershed, northwestern Ethiopian highlands. Both disturbed and undisturbed soil samples that were taken from three adjacent LULC (natural forest, grazing and cultivated lands) and elevation (2238–2300, 2400–2600, and 2700–2800) classes analysed for the selected physico-chemical SQ indicators. Two-way ANOVA, Tukey’s multiple comparison test and SQ deterioration index were computed. The impact of LULC and elevation was found significant on key SQ indicators. In cultivated and grazing lands, soil organic matter (SOM) and soil nutrients like total nitrogen declined significantly (p < 0.01). Conversely, bulk density increased significantly (p < 0.01). The divalent basic cations (Ca2+ and Mg2+), cation exchange capacity and pH significantly (p < 0.01) decreased in upper elevation. Synergetic effect of LULC and elevation variations was found significant (p < 0.01) on SOM, total nitrogen, available phosphorus, water content at field capacity and soil particle distribution (silt and clay). Thus, elevation specific land management strategies that improve these SQ indicators need to be emphasized.

Abstract

Researches on the use of waste vegetable (tomatoes, peppers) and fruits (apples, plums) in order to improve the nutritional quality of the soil have been performed. The content in nitrogen, phosphorus, potassium, humus, organic matter have been analyzed in fruits and vegetable waste and also in soil before and after mixing with each waste at a ratio of 1:2.5. Analyses were done by using current analytical methods (chemical and absorption molecular spectrometry) after previous mineralization of samples with appropriate reagents. To investigate the effect of vegetable wastes on the plants growth, wheat has been planted in the witness soil sample and in the mixed soil with wastes. The nutrients concentration in vegetable waste was higher than in fruit waste (33-75%). Available phosphorus concentration increased about two times in soil with fruit waste while in the soil with vegetable the increase was of about 3 times. Potassium concentration increased about three times in soil mixed with both types of waste. Although potassium and organic matter have higher values in the soil amended with fruit waste than in the witness soil, the height of the wheat was similar with those in the control soil due to the limiting role of phosphorus.