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Early cabbage was grown in a field experiment in two treatments, with and without weed control, to test the following fertilizers: ammonium nitrate and Entec 26-a, a new formula nitrogen fertilizer containing a DMPP nitrification inhibitor, applied in single preplant or split doses, and calcium cyanamide (Perlka), supplied only prior to the planting of cabbage. All the sources of N were used in amounts supplying 150 kg N ha-1. The fertilizer Perlka was applied 2 weeks before planting cabbage transplants, while Entec 26 and ammonium nitrate were introduced to soil 3 days before that. All the fertilizers were incorporated into the soil by harrowing. In the treatments with split N application, top dressing was conducted just after the cabbage plants were uncovered, which took place 3-4 weeks after transplanting. The experiment was established in a one factorial design with four replications. The results proved high efficiency of nitrogen fertilization, which – when applied at a dose of 150 kg N ha-1 - enhanced the yield of early cabbage by about 50% compared to the treatment without N fertilization and weed control. Ammonium nitrate and Entec 26 appeared to be equally valuable sources of this nutrient, both in single and split doses, in each year of the investigation. Calcium cyanamide produced the highest marketable yield of heads with a significantly lower mean content of nitrates in edible parts. Another big advantage of this N source is its high efficiency in reducing weed infestation during the whole vegetation period.
Strong and long-lasting human activity in most European lowland river valleys results in narrowing the area of inudated ecosystems from wide floodplains to the space between embankments. This concerns especially regulation and drainage works, as well as hydrotechnical infrastructure construciton. The Warta Mouth National Park is a suitable region for inudated habitats research – over 5000 hectars of flood reservoir gathers here excess of water every year. It is one of the biggest flooded area in this part of Europe. The aim of this study was the analysis of flora changes over the dozen of years. The two inudated surfaces, different in respect of land use, were compared. Results indicate significant influence of land use on flora composition.
Contamination of soils around mines by heavy metals has not yet received the serious attention that it deserves in South Africa. The current study evaluated the concentrations and levels of pollution by trace metals in soils around a Ferro-chromium mine in South Africa. Soil samples were collected from 20 locations in four different directions, namely southwest, southeast, northwest, and northeast of the mine. The soils were analyzed for trace metals concentrations using ICP-MS. The result revealed that soil pH was in the acidic medium with a very low level of soil organic matter. The concentrations of elements from the soil followed the order Al > Fe > Ca > Mg > Cr > Na > Mn > Ni > Zn > V > Cu > Pb > As > Cd. Higher concentrations for all the elements were recorded from the topsoil and also from the southwestern direction, and the differences in the concentrations were significant (p> 0.05). A highly significant positive correlation of Fe and Cr with Ni and with each other (0.42 ≤ r ≥ 0.82) were recorded. The Pi (pollution index) and I-geo (geoaccumulation index) indicated that the soils around the mine were severely contaminated with Cr and Ni. The concentrations of Fe, Cr, and Ni from the soil samples were high enough to cause serious health problems for people living in the area.
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Uliczny ogródek kawiarniany jest to miejsce tymczasowo wyodrębnione w przestrzeni pasa drogowego lub chodnika. Jego wyposażenie stanowią: stoliki, krzesła, parasole, stojaki z menu, kwietniki i inne elementy dekoracyjne. Ulice miast są miejscem, gdzie roślinność powinna być szczególnie doceniana. Należy poszukiwać nowych gatunków roślin, które dobrze rosną nawet w bardzo trudnych warunkach. Oprócz sprawdzonych powinno się stosować także nowe rozwiązania techniczne. Wystrój ogródka należy zaplanować w odpowiednim stylu zaakceptowanym przez konkretne miasto i pasującym do charakteru dzielnicy lub otoczenia budynku. W wielu badaniach potwierdzono, że miejsca udekorowane żywą roślinnością są częściej i chętniej odwiedzane przez klientów. Te małe przestrzenie mają nie tylko wartość przyrodniczą, ale także społeczną i kulturową. Urządzenie atrakcyjnej wizualnie i jednocześnie funkcjonalnej przestrzeni kawiarnianego ogródka to wyzwanie, z którym mierzy się coraz więcej architektów, a projekty tego typu zlecają kawiarnie, restauracje, hotele, biurowce czy ośrodki wypoczynkowe.
In the field experiment with cabbage cv. ‘Menza F1’ fertilized with 150 and 250 kg N·ha⁻¹, the first weeding started 3, 6, 9, 12 weeks after transplanting, including unweeded control. Higher dose of nitrogen especially in treatments with delayed weed control affected in significant increase of marketable yield, as well as the mean weight of cabbage heads in comparison to the dose of 150 N·ha⁻¹. The highest yielding was recorded in treatment where the first weeding was conducted 3 weeks after transplanting. The delay of this operation to 6, 9, and 12 weeks after transplanting caused the decrease in marketable yield by 16.0%, 33.1% and 48.4%, respectively. The dose of 250 N·ha⁻¹ contributed to the slight decrease of dry matter, total and reducing sugar contents, and higher accumulation of nitrates in edible parts of cabbage heads. Late start of weed removal was disadvantageous for dry matter and sugars content and caused higher nitrates accumulation in cabbage.
Macrophytes are important component of the aquatic ecosystem and broad changes in the abundance of individual species and community composition provide valuable information on how and why an ecosystem might be changing. Santhapettai lake is one of the biggest fresh water lake in Villupuram district, Tamil Nadu. The physico-chemical parameters were analysed for one year (October 2012-September 2013). Quadrates were laid randomly and extending from shoreline towards the lake center. The macrophytes falling in each quadrate were sorted species wise, identified and data were recorded. The plants have been identified from fresh materials with the help of different floras. In this present investigation, a total of 33 species belonging to 23 families and 28 genera were identified under algae, pteridophytes, dicotyledons and monocotyledons. Further, the plants were classified in morphological group as floating (7), submerged (1), submerged anchored (13), floating leaved (1) and emergent anchored (11). The coverage/spread of macrophytes along the shorelines was higher compared to the centre of the lakes where the species composition was found reduced. Assessment of biota, continuous monitoring and conservation lake are the important components to safeguard the biological wealth of lentic and lotic freshwater ecosystem.
For testing, soil samples were drawn from a crop rotation experiment set up on leached brown soil, developed from loess of The Nałęczów Plateau. The samples were taken from humus horizon (0+20 cm), from crop rotation with diversified share of cereals. In rotation with 50% cereal share, there were grown the following plants: sugar beat, spring barley, mixture of leguminous plants and winter wheat. In rotation with 75% share of cereals, sugar beat, spring barley, oats, mixture of leguminous plants and winter wheat were grown. And as aftercrops - oil radish, charlook and phacelia. In soil samples, beside basic chemical properties, there were determined total contents of phosphorus, potassium, magnesium and its assimilable forms. The same chemical elements were determined in plants. The total contents of phosphorus, potassium and magnesium were close to the same value in soils, from under all crop rotations. But the contents of assimilable forms of these elements were different depending on crop rotation. In plants of stubble field aftercrops, the crop rotation had no influence on contents of analysed chemical elements.
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