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Abstract

Study of bacterial transport and retention in soil is important for various environmental applications such as groundwater contamination and bioremediation of soil and water. The main objective of this research was to quantitatively assess bacterial transport and deposition under saturated conditions in calcareous soil. A series of leaching experiments was conducted on two undisturbed soil columns. Breakthrough curves of Pseudomonas fluorescens and Cl were measured. After the leaching experiment, spatial distribution of bacteria retention in the soil columns was determined. The HYDRUS-1D one- and two-site kinetic models were used to predict the transport and deposition of bacteria in soil. The results indicated that the two-site model fits the observed data better than one-site kinetic model. Bacteria interaction with the soil of kinetic site 1 revealed relatively fast attachment and slow detachment, whereas attachment to and detachment of bacteria from kinetic site 2 was fast. Fast attachment and slow detachment of site 1 can be attributed to soil calcium carbonate that has favorable attachment sites for bacteria. The detachment rate was less than 0.02 of the attachment rate, indicating irreversible attachment of bacteria. High reduction rate of bacteria was also attributed to soil calcium carbonate.

Abstract

The aim of this study was to investigate rendzinas diversity on the area of the Ojców National Park (ONP), southern Poland. Moreover, the paper aims to identify the relation between relief and soil cover slope position and its influence on classification as well as the occurrence of lithological discontinuity. The studied soils were classified as brown and chernozemic rendzinas. Rendzinas in the area of the ONP are located mainly in the middle slope position where Upper Jurassic limestones regolith is mixed with loess sediments. This situation leads to vertical heterogeneity of soil texture (and formation of rendzinas with lithological discontinuity) within the soil profile. Surface horizons were mainly characterized by silty texture while in deeper horizons there was a more clay-like texture, which was the result of weathering Jurassic limestones located in deeper parts of soil profile. In turn, uniform shallow rendzinas occurred only on exposed rocks composed of limestones, where loess cover was absent. The character of ONP’s soils is also the result of parent material heterogeneity conditioned by long-term changes e.g. denudation processes and/or weathering. In order to assess soil heterogeneity, ‘lithological discontinuity indices’ as well as ‘uniformity values’ have been applied.

Damp beech forests on calcareous tufas in the Parsęta River basin (Western Pomerania)

Damp beech forests in the Parsęta River basin (Western Pomerania) constitute a rare and unique type of beechwood community in post-glacial landscape of the Pomerania region. They grow on calcareous soil of pararendzina type formed from calcareous tufas and are characterized by the presence of two orchids Cephalanthera rubra and Neottia nidus-avis accompanied by many rare and endangered plant species occurring in habitats rich in calcium.

Abstract

The architecture of the tejocote (pronounciation: tehocote) - a Mexican fruit trees is described. There is a great morphological diversity among the tejocote clones growing in Germplasm Bank of the Autonomic University of Chapingo, Mexico. The common character of all hawthorns in this bank is that the inflorescence axis dies after shedding the reproductive parts (flowers or fruits) but remains on the tree, and the growth continues from the bud situated below the dead part. The growth and ramification habit were described as long shoots showing marked apical dominance and as the complex of shoots showing week apical dominance. The non-pruned trees of tejocote clones used as fruit trees form strong natural crown. The architecture of it is similar to the “Troll’s model” of Hallé and Oldeman (1970). Metamorphosis and reiteration are relatively frequent. The inflorescence structure was described, as well as the types of thorns in clones, which have thorns. Tejocote hawthorn may probably be an interesting fruit tree for countries with warm climate and a long dry period. It is also well adapted to shallow calcareous soils.

Abstract

GF677 is an interspecific hybrid which has important value in terms of economic and horticultural characteristics. The use of this rootstock for some stone fruit trees including almond and peach has been increased dramatically in recent years. It has some useful characteristics i.e. high tolerance to calcareous soil, a strong root system and suitability for poor soils, but its propagation is difficult. This study aimed to evaluate the effect of putrescine (PUT) on the rooting of GF677 cuttings under mist conditions. Treatments used include PUT concentrations (2 and 4 mM for 5 minutes), indole-3-butyric acid (IBA) using the quickdip method (1500 and 3000 mg l-1 for five seconds), and a commercial rooting powder and control (without any rooting substances). Treatments were applied at the end of the dormant season. Growth data were obtained 120 days after the treatments. The results showed that application of 1500 mg l-1 of IBA and commercial rooting powder improved GF677 rooting, but 3000 mg l-1 of IBA resulted in toxic effects on rooting and foliage of the cuttings. Cuttings treated with PUT solutions showed the best roots and shoots in terms of the number and quality. In conclusion, IBA may be replaced by PUT in the rooting process of GF677 cuttings.

Abstract

CropSyst model can be used as irrigation water management tool to increase wheat productivity with poor quality water. The objective of this study was to calibrate CropSyst model for wheat irrigated with fresh and agricultural drainage water. To do so, three field experiments were conducted during three successive seasons in Nubaria Agricultural Research Station, Egypt representing the newly reclaimed calcareous soils. In the first season the treatments were 100% crop evapotranspiration (ETc) of fresh water (FW) and 100% ETc of agricultural drainage water (DW), while in the second and the third seasons, the treatments were 100% ETc of FW, 100% ETc of DW, 120% ETc of DW and 130% ETc of DW. From these results one can concluded that deducting 5% of the applied water to all treatments reduced yield by 3, 5 and 7% in the first, second and third growing season, respectively as a result of heat stress existed in the 2nd and 3rd seasons during reproductive phase. Furthermore, deducting 5% of the applied water from all treatments in the vegetative phase only resulted in lower yield losses. Thus, using CropSyst model could guide us to when we could reduce the applied irrigation water to wheat to avoid high yield losses.

Abstract

It is suggested that calcareous soils formed from calcareous gyttja were termed quaternary rendzinas, as indicated by Uggla. Their differentiation is connected with the amount of calcium carbonate and anthropogenic modification of surface horizon. Soils being in the initial phase of organic matter accumulation are suggested to be termed initial quaternary rendzinas, whereas the soils that have humus horizon more than 10 cm thick - proper quaternary rendzinas. Taking into consideration the fact that humus horizon of these soils is developed during siltation with alluvial or deluvial deposits, separation of calcareous post-lacustrine soils in alluvial and deluvial soils should be considered alternatively.

Abstract

The largest natural population of shrubby cinquefoil (Potentilla fruticosa) in the Baltic States was observed in the field to reveal the scale-dependent explanatory value of site characteristics for subsequent spatial distribution modelling of the species. About 700 km was crossed during field observations in 2008–2014. Thinning of the raw field records to ensure a distance of at least 50 metres between each point yielded 1459 presences and 7327 absences. These occurrence data were related to present and historical land cover, soil, elevation, human population density, the proportion of presence sites, and P. fruticosa mean coverage in the neighbourhood. Boosted classification tree models were used to compare the value of 60 individual site features at thematically and spatially different levels of generalization as indicators of the species’ presence or absence. P. fruticosa presence is significantly non-random regarding most of the studied site features but only a few of these are valuable predictors. The proportion of presences in the neighbourhood had the highest indicative value. P. fruticosa occurrence also coincides with moist thin calcareous soils according to the soil map, with larger scrubland patches according to the topographical database, and with tussock areas according to a topographical map from the 1930s. The explanatory value of nominal site characteristics primarily drops when the most indicative category is merged with other classes to form a more general category. Site characteristics calculated at the observation point are not always the most effective predictors for P. fruticosa occurrence – features of the neighbourhood are related to the occurrence as well. The study area was classified into: confirmed absence area, unclear presence/absence area and probable presence area. Subsequent distribution modelling in the unclear area should be targeted on a species presence/absence, while abundance could be the priority within the probable presence area.

Abstract

The object of this study was to compare the results obtained with four methods of determination of cation exchange capacity (CEC) and sum of exchangeable cations (Ca, Mg, K) in soils. One of these methods is Kappen’s method and the others methods are based on different extracting reagents: sodium acetate (pH = 8.2), barium chloride and hexaamminecobalt(III) chloride. Values measured with barium ions and hexaamminecobalt(III) ions as index cations are very comparable and these two methods can be considered as equivalent. Kappen’s method gives overestimated results, especially for acid soils reach in organic matter and very calcareous soils. Sodium acetate, buffering the pH of the extracting solution, causes increase of numbers of negatively charged sites and particularly those bonded to organic matter and for this reason values obtained with this method are overestimated. Nevertheless, it is possible to correct this error for a given soil sample by regression equation considering pH of soil, clay and organic carbon content.

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