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Fertilizing cultivable plants is an effective way of improving yield quantity and quality. The studies conducted in the years 2008–2009 were aimed at determining the relationship between the kind of nitrogen fertilizer, manner of its application, as well as the dose of calcium carbonate and the plant unit weight, as well as chemical composition of spinach beet, grown in glasshouse in the spring period. Nitrogen was applied in the form of ammonium sulphate and urea in a localized form (N-deposit) and in the form of solution. Calcium was administered in the form of calcium carbonate in the doses of 5 and 15 g · dm-3 of substratum. The length of leaves, plant unit weight and selected parameters of beet leaf utility value were assessed. The substratum was also analyzed after plant harvest. The highest unit weight of plants was obtained with the application of ammonium sulfate in the form of a solution with a lower calcium carbonate dose, compared to the remaining combinations. The examined spinach beet plants were distinguished by high contents of dry matter, protein, total nitrogen, potassium, calcium and magnesium The chemical composition of leaves was significantly differentiated, depending on the examined factors. The contents of nitrates in the leaf dry matter ranged from 0.26 to 0.45%, depending on the kind of nitrogen fertilizer and manner of its application. The applied nitrogen fertilization to a small extent influenced the concentration of nitrates in beet leaves. More nitrates were contained in plants fed by a higher dose of calcium carbonate, compared to the plants which were given a lower dose of CaCO3. The highest content of vitamin C and the lowest share of nitrates in leaf dry matter were obtained with the application of urea in the form of deposit with a lower dose of calcium carbonate.
The photosynthetic activity of phytoplankton (in pelagial) and macrophytes (in littoral) is considered to be one of the main factors affecting the carbon cycle in lakes. This concerns in particular hardwater ecosystems, where most of the carbon is available in the form of Ca- or Mg-bicarbonates. In such ecosystems charophytes (macroscopic green algae, forming dense meadows) are regarded as the most effective carbonate producer due to the HCO3— utilization and the formation of thick CaCO3 encrustations.Calcium carbonate and biomass production of charophytes were studied in a small and shallow charophyte-dominated Lake Jasne (Western Poland). Fresh and dry weight of plants, percentage contribution of calcium carbonate and production of CaCO3 per 1 m2 were studied at three depths (1, 3 and 5 m) in three sample sites (each sampled area −0.04 m2). Additionally, physical-chemical parameters of water samples were studied. It was found that the dry weight of charophytes and the values of calcium carbonate were similar for all sites but varied for depth of sampling. The dry weight exceeded 2000 g m-2 (average 1165 g m-2) at the most shallow sample sites. CaCO3 encrustations constituted from 39.5% at the depth of 5m, to over 82% of the charophyte dry weight at the depth of 1m. The maximum and average values of carbonates precipitated by charophytes were 1696 g m-2 and 891 g m -2, respectively, and exceeded results reported so far. The results of physical-chemical analyses revealed no statistically significant differences between all the sample sites. Nevertheless, distinct correlations were found between dry weight of charophytes, carbonates precipitated by charophytes and some physical-chemical properties of water from the sample sites. The results highlight the habitat engineering role of charophytes, evidenced in particular by great amounts of biomass influencing sedimentary processes and biogeochemical cycle within littoral zone.
Primary producers are able to strongly affect calcium budget in hardwater lakes. The relative contribution of phytoplankton and charophytes to water decalcification (by precipitation of calcium carbonate) is, however, unclear. In this study we checked the effect of natural phytoplankton community and a charophyte (Nitellopsis obtusa) on the decline of calcium concentration in experimental outdoor conditions. The experiment was carried out in original lake water and two variants of enrichment with inorganic nitrogen and phosphorus to test the changing efficiency in decalcification by both primary producers. At low nutrient concentrations, N. obtusa was responsible for calcium decline in original lake water by 12 mg Ca+2 dm–3 during 20 days of experiment. In these conditions the effect of phytoplankton was negligible. In lake water enriched with nutrients, the exponential growth of phytoplankton led to the decrease of calcium concentration from initial 35 mg Ca+2 dm–3 to 9 mg Ca+2 dm–3 in the same time period. The maximum effect of N. obtusa was the same as in original lake water but manifested itself earlier to decline in the end of experiment. Supersaturation of water with calcium carbonate was always more than threefold and saturation index reached 27 in mixed cultures of phytoplankton and N. obtusa in lake water enriched with nutrients. In this context we hypothesise on a possible role of charophytes as nucleation sites necessary for calcite precipitation. Based on our own and literature data we also discuss expected immobilisation of phosphate incorporated in calcite precipitated by the growth of phytoplankton and N. obtusa.
Seedlings and young plants of lenten rose (Helleborus orientalis Lam.) were grown for two years (2006–2007) in containers on peat substrate which was deacidified with calcium carbonate at doses (g∙dm⁻³) of 2.5, 5.0, 7.5 and 10.0. Within each dose of CaCO3 plants were divided into two groups, of which one was fertilized with a lower (0.1%) and the other with a higher (0.3%) concentration of Peters Professional PL Special (15:11:29). The CaCO3 dose applied to deacidify high moor peat had a significant effect on plant height irrespective of their age. In the first and second year of pot cultivation the tallest plants were produced on a substrate to which calcium carbonate was added at 2.5 g·dm⁻³ CaCO3, while the lowest at 10 g·dm⁻³ CaCO3. The number of leaves and flowering of lenten rose did not depend on the amount of calcium carbonate introduced to the substrate. Fertilization of lenten rose cv. ‘New Hybrids F1’ with Peters Professional PL Special (15:11:29) at a higher concentration (0.3%) made it possible to produce taller plants, with a larger number of leaves, and earlier and more abundant flowering.
This paper presents the experimental data on the amount of available phosphorus in a sandy soil assessed by the Egner-Riehm (DL) method and water extraction method. Simultaneously, the effects of the addition to the soil of calcium oxide, calcium carbonate, powder super- phoshate, and soil incubation on the P content was assessed. It was found that available phosphorus content in the soil extracted by water was lower than that assessed by the Egner-Riehm method. The effect of lime application was different in the extracts obtained by the compared methods. As effect of liming, the available phosphorus content assessed by the water extraction method was smaller. The addition to the soil of powder superphosphate caused an increase of the available phosphorus recovery by both methods. The water extraction allowed 20% of the added phosphorus to be recovered.
Within the Ocimum genus there occur about 200 species in different varieties and forms. They differ in the essential oil content and quality, as well as in many morphological features. The studies conducted in the years 2008–2009 were aimed at defining the effect of basil cultivar (‘Kasia’ and ‘Wala’), as well as of the differentiated doses of CaCO3 (6 or 12 g·dm-3 of substratum) upon the biological value and chemical composition of the oil in the examined plants, grown in pots filled with transitory peat. A significant interaction was reported between the examined cultivar and CaCO3 dose upon the yield of fresh basil plant weight. The highest yield (172.3 g·plant-1) was obtained from plants of ‛Kasia’ cultivar, when a higher dose of CaCO3 was applied (12 g·dm-3 substratum). Lack of significant effect of calcium carbonate dose was reported upon the yield of fresh basil plant weight. In the examined objects similar fresh weight yield values were obtained. At a higher dose of calcium carbonate the unit plant weight equaled 165.9 g·plant-1, and at a lower dose of CaCO3 it was 160.2 g·plant-1. The percentage of dry matter significantly depended on the cultivar. Basil of ‘Wala’ cultivar had higher dry matter content, (32.0%) compared to ‘Kasia’ (25.6%). Both the cultivar and calcium carbonate dose significantly affected the vitamin C contents in fresh basil herb. Increasing the CaCO3 dose from 6 g·dm-3 to 12 g·dm-3 caused the increase of vitamin C concentration by 12.6%. Higher essential oil contents was characteristic of the herb of ‘Kasia’ plants – 1.33% compared to ‘Wala’ cultivar, in whose herb 1.03% of oil was determined. The qualitative composition of isolated oil depended on the examined factors. The predominating compounds were: linalool, 1.8-cineole, geranyl, D germacrene, γ-cadinene, Epi-α -cadinole. A certain differentiation was found in the contents of particular compounds in the essential oils of ‘Kasia’ and ‘Wala’ plants, as the effect of calcium nutrition.
Thyme belongs to herbal plants, the yield and quality of which depend on biological factors, agrotechnical procedures and the way of processing and storage. Basic factor differentiating the biological value of plants is fertilization, including manure, as well as plant growth and development, which is significantly influenced by the pH of the substrate, in which the plants are grown. The aim of the study was to determine the effect of manure dose (12.5 and 25 g·dm–3) and calcium carbonate (5 and 15 g·dm–3) on the yield and biological value of thyme. The fresh thyme mass yield was changed under the influence of the factors used. The highest yield of raw material was recorded after using a high dose of manure and calcium carbonate. Significantly higher concentration of essential oil in thyme was found after feeding the plants with higher dose of manure. The inverse relationship was demonstrated for the amount of L-ascorbic acid that decreased with the increase in manure dose. Calcium fertilizers not only serve to regulate the acidity, but are also a source of calcium for plants. After applying a higher dose of CaCO3, significant increase in the yield of fresh thyme mass was observed and higher dry matter content was recorded
Basil, cultivated as a medicinal and seasoning plant, has strict requirements as to climate, as well as soil fecundity and humidity. The herb harvested during flowering period, contains, besides valuable essential oil, plant dye, vitamins and mineral components. The undertaken studies were aimed at analyzing the contents of macro and microelements in the herbs of two basil cultivars (‘Kasia’ and ‘Wala’), depending on the doses of calcium carbonate – 6 and 12 g·dm-3 substratum. The total nitrogen contents was on quite an even level – from 5.23 to 5.43% d.m. A significant effect of the examined cultivar was reported upon the N-total contents, whereas the calcium carbonate dose did not differentiate the content of this component in a plant. Significant effects of calcium fertilizer dose and cultivar were reported upon potassium and calcium contents in basil herb. The double dose of CaCO3 caused the decrease of potassium and calcium amounts in the plant. Higher concentrations of K and Ca were found in the herb of ‘Kasia’ than ‘Wala’ cultivar. Higher zinc, manganese and copper contents were found in plants of ‘Wala’ cultivar, as compared to plants of ‘Kasia’ cultivar. Doubling the dose of calcium carbonate caused the decrease of manganese, copper and iron concentrations in basil herb, as compared to a single dose. Only as to zinc no such response was reported. The concentrations of nutrients in the examined substratum was differentiated depending on the analyzed factors.
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