Spatial and temporal characterization of soil properties in agro-ecosystems is crucial for monitoring the evolution of soil functions and for understanding the main influential processes. Moreover, ...the objective mapping of soil properties in agro-ecosystems is urgently needed for regional planning purposes and the proper choice of land management practices. In this work, the geostatistical analysis of a dataset of soil properties, derived from 2411 soil samples collected in Vukovar-Srijem County (Croatia), highlighted the multiple benefits of a spatial-statistical approach. The main aim of this paper is to jointly examine short-range (i.e., within-field) and regional spatial variability of several soil chemical properties: soil pH, organic matter (OM), plant available phosphorus (AP) and potassium (AK). The available sampling network, characterized by a set of 2411 (0–30cm depth) irregularly and field-clustered soil samples, allowed to derivate of two typologies of soil nutrient maps by means of ordinary block kriging: within-field high-resolution maps (block size 250m) and regional low-resolution maps (block size 2000m). Soil pH and OM had lower variability compared to AP and AK. The OM content and pH ranged from 1.24% to 5.25% and from 3.69 to 7.84, respectively. Almost 94% of all samples had an OM content below 3%, indicating the need for future adoption of environmentally friendly soil management in this county. The mean values of AP and AK were 173mgkg−1 and 238mgkg−1, respectively, indicating a moderate supply of these nutrients. Geostatistical analysis revealed that the best-fit models were spherical for pH and AP, with moderate spatial dependency, and exponential for OM and AK, with strong spatial dependency. The within-field high-resolution soil property maps can be used as guidance for site-specific fertilization and liming. In addition, the regional maps derived for larger interpolation support provide quantitative information for regional planning and environmental monitoring and protection purposes. Consequently, the multi-resolution mapping of soil properties and the analysis of their spatial variability highlighted possible connections with influential factors and processes, including the relationships with different soil types. Finally, quantification of the spatial variability of soil properties by means of variogram models constitutes a basis for optimizing soil sample spacing for mapping purposes in the studied region.
•Short-range and regional spatial variability of soil chemical properties was investigated.•The investigated soil properties (pH, OM, AP and AK) are characterized by different spatial patterns.•The spatial patterns of soil properties suggest the likely influence of antrophic processes.•Occurrence of highly acidic areas are mayor restricting factor for crop production.•Low OM content indicates the need for environmental sustainable management strategies.
The stationary field experiment with increasing rates of NPK 8:26:26 fertilization was conducted on acid soil. Three steps of NPK-fertilization were applied (kg ha-1) as follows: F-1 = 103 N + 52 ...P2O5 + 52 K2O, F-2 = 133 N + 182 P2O5+ 182 K2O and F-3 = 183 N + 312 P2O5+ 312 K2O. Six hybrids of maize (the growing seasons 2008-2010) and winter wheat (2010/2011) cultivar Renata were grown in crop rotation. In our study, considerable subsequent effects of applied fertilization on wheat yields were found as follows: 7.44 t ha-1 (F-1), 8.74 t ha-1 (F-2) and 8.43 t ha-1 (F-3). However, maize responded by yield decreases up to 7% (3-year means: 10.76, 10,50 and 10.02 t ha-1, for F-1, F-2 and F-3, respectively).
The purpose of this article was to compare soil P extraction by sodium bicarbonate solution (Olsen P) and by ammonium lactate (AL P) in calcareous soils in Croatia and to create a model for ...predicting AL P values using the correlation of these soil tests and common soil analysis data in Croatia. Soil samples were collected, near Opuzen city, in the valley of the River Neretva, in 2005. The results of these studies confirmed significant correlation between soil P extracted by Olsen (NaHCO3) and by ammonium lactate (AL P) solution in calcareous soils from the Neretva river valley. The developed model is useful for providing fertilizer recommendations based on AL P soil-test results from Croatian soils using existing ammonium lactateextractable P calibration expecially for the calcareous soils in Croatia in the valley of the Neretva River.
The field experiment was conducted (April 2004) on planosol (a = ordinary fertilization, b = a + P1, c = a + P2, d = a + P3, e = a + P1, f = a + P2, g = a + P3, h = a + P2K2). The amounts of added ...either/or phosphorus (P2O5) and potassium (K2O) were (kg ha-1) 500, 1000 and 1500, for the step 1, 2 and 3, respectively. Nitrogen amount was equilized for all treatments by adequate quatities of CAN (calcium ammonium nitrate: 27% N). In general, influences of P and K fertilization on mobile fraction (NH4-Acetate + EDTA; pH 4.65; determination using inductively coupled plasma) of 23 elements in soil (sampling in November 2005) were low. For example, non-significant differences among the treatments were found for 13 elements (Mg, S, Fe, Mn, Zn, Mo, Cr, Ni, Al, B, Ba, Co and Pb). Further, for three elements (Se, As and Hg) the concentrations were very low and under detectable ranges of the applied methods. P fertilization significantly influenced on soil P (+145%), Ca (+58%), Sr (+53%) and Cd (+12%), At the same time, K fertilization resulted by significant increases of soil K (+77%) and decreases of soil Cu (-17%), and Na (-54%). However, the amounts of tested elements in soil were mainly low (the control treatment in mg kg-1: 84 for P, 188 for K, 362 for Ca, 3.12 for Cu, 1.15 for Sr, 23.7 for Na and 0.084 for Cd). It is evidently that in our study low levels of harmful elements were found.
This research examined influence of different amounts of bovine manure supplemented with technological wastewater on dominant physiological groups of microorganisms in arable soil layer (0-30 cm) of ...semigley loess type of soil during silage corn vegetation. Exact fertilizing vegetation experiment was conducted in 2006, in 7 variants and 4 repetitions. Amount of manure supplemented with disinfectants applied in arable soil layer was vital for soil biogenity, what had direct influence on silage corn yield. It was determined that smaller amounts of manure (10-30 m3ha-1) caused slight and relatively short-term decrease in amount of aminoheterotrophs, aminoautotrophs and non-symbiotic fixators of elementary nitrogen (Azotobacter chroococcum), which resulted in silage corn yield of 52.32-54.46 t ha-1of fresh plant mass. While larger amounts of manure (65 m3ha-1) had stronger and long-lasting toxic effects on the same physiological groups of microorganisms, what caused lower silage corn yield (50.08 t ha-1).
Nine maize (Zea maysL.) hybrids were grown under field conditions on two soils (eutric cambisol and eugley) for two growing seasons (2004 and 2005). Seven domestic maize hybrids (OsSK444, OsSK554, ...OsSK644 and OsSK713, Bc66-61 and Bc778) and two foreign (ZPSK633 and ZPSK778 - from Serbia) were used. The field trial was conducted in five replicates (gross of basic plot 56 m2). Grain yield in 2005 was 13% lower than in 2004 (8.28 and 9.53 t ha-1, respectively). Yields on eutric cambisol were lower than on eugley (6.96 and 10.84 t ha-1, respectively). Also, differences of yields among the hybrids were very significant. The hybrid Bc778 yielded 10.37 t ha-1or 32% more compared to the hybrids Bc592 and ZpSK704. Leaf-N was in 2005 11% higher than in 2004 (means 2.53% N and 2.81% N, respectively), while leaf-P (mean 0.28% P) and –K (mean 1.68% K) differences between two years were non-significant. Leaf-K under eugley conditions was 25% lower than on cambisol (means 1.44% K and 1.92% K, respectively). Differences in leaf composition among the maize hybrids (influences of genotype) were in the ranges from 2.59% N to 2.76% N, from 0.25% P to 0.30% P and from 1.62% K to 1.76% K. In general, low connection was between leaf nutritional status and yields probably because relative favorable soil fertility of both soil types, although the first-ranged hybrid regarding yield (Bc778) was in the group of the hybrids with the highest leaf-N, -P and –K. Also, two low-yielding hybrids (Bc592 and ZpSK704) characterized considerably lower leaf K.
The investigation was conducted in Magadenovac glasshouses, eastern Croatia during seventeen years (1985. - 2002.). In that period, the glasshouse production of vegetables and flowers was intensive ...during the whole year. The trial was set up on 500 m2. Because of often crop rotation during the same year, soil tillage must be done fast and soil must be homogenized till depth of about 40 cm. Often in practice it is not possible to plough because of numerous reasons and then main mechanization is roto-digging machine. The aim of this investigation was to determine the consequences of long-term application of the special roto-digging machine and dynamics of organic matter and humus content during 17 years. For this purpose, multiple chemical and physical analyses were done. It was determined that, by intensive production during 17 years, organic matter content in soil surface layer significantly decreased (1995 year - 8.60% and 2002 year - 5.00%). In subsurface layer (35-50 cm) organic matter content decreased by about 50%. At the same time, by decreasing organic matter content soil became more acid, because pH value measured in 1M KCl after 17 years was by 1.4 units lower in the surface layer, and by about 0.5 units lower in subsurface layer. Finally, soil became acid (pHKCl = 4.8). Decreasing in organic matter and humus content led to soil compaction, decreased soil porosity and degradation of other physical and chemical properties. It can be concluded, that it is necessary to import complete agricultural operations relative to soil tillage for soil preserving.
