Nowa wersja platformy, zawierająca wyłącznie zasoby pełnotekstowe, jest już dostępna.
Przejdź na https://bibliotekanauki.pl
Ograniczanie wyników
Czasopisma help
Lata help
Autorzy help
Preferencje help
Widoczny [Schowaj] Abstrakt
Liczba wyników

Znaleziono wyników: 25

Liczba wyników na stronie
first rewind previous Strona / 2 next fast forward last
Wyniki wyszukiwania
Wyszukiwano:
w słowach kluczowych:  nutrient balance
help Sortuj według:

help Ogranicz wyniki do:
first rewind previous Strona / 2 next fast forward last
EN
The influence of mineral fertilizers on productivity and nutrient balance of sod–podzolic soil when growing cereal meadow agrophytocenosis under conditions of Precarpathians of Ukraine was researched. It was found that the dependence of cereal agrocenosis productivity on the doses and ratios of N, P, K in mineral fertilizers is described by equation (polynomial) of the 2nd degree. Among the mineral elements, nitrogen is has the greatest influence on grass productivity. When applying the total dose of N75 with even distribution of nitrogen under each of three mowings on different backgrounds of phosphorus-potassium fertilizers, the productivity of cereal grass increases by 2.82–3.06 t ha-1 of dry mass, and when applying N150 by 3.33–4.93 t ha-1 of dry mass. Recoupment of nitrogen fertilizers per 1 kg by yield increase when applying N75 is 38–41 kg of dry mass, which is 4–5 kg more compared to the application of N150. The indices of phosphorus and especially potassium removal, as well as deficiency of these elements in the balance increased along with nitrogen dose. Independently of the phosphorus and potassium doses, the lowest indices are fixed on a nitrogen–free background, and the highest – on the background of N150.
PL
Problem zanieczyszczeń obszarowych jest aktualny od kilkudziesięciu lat. Szczególnym zagrożeniem dla środowiska jest rozpraszanie niewykorzystanych w produkcji rolnej składników pokarmowych. Emisja makroskładników do ekosystemów naturalnych może wywoływać niekorzystne zmiany fizyczne, chemiczne oraz biologiczne. Dlatego tak ważne są kontrola i monitoring gospodarstw rolnych w kontekście rozpraszania zanieczyszczeń do środowiska. Jedynym narzędziem kontroli produkcji rolniczej jest bilans składników biogennych. W krajach Unii Europejskiej oraz krajach należących do OECD jest on obowiązkowy. Niestety, brak standaryzacji metody, z uwzględnieniem strefy klimatycznej bądź uwarunkowań regionalnych, oraz opracowania poprawnej formuły bilansowej powoduje, że uzyskane wyniki są mało miarodajne i często nieporównywalne. Takie podejście może powodować niewłaściwą weryfikację wyników, spadek opłacalności produkcji oraz niewłaściwą ocenę stanu środowiska.
EN
The aim of the study was to characterize national and foreign nutrient balancing methods used for controlling and monitoring of agricultural production in the context of their dispersion into the environment. The problem of non-pointed pollution is present from several decades. Particular threat to the environment is emission of unused nutrients from agricultural production. Overenrichment of natural ecosystems by macronutrients may cause adverse effects to physical, chemical and biological properties. Therefore, it is important to control and monitor farms in the context of emissions to the environment. The only tool of controlling of farms is the nutrient balance. In the European Union and OECD countries it is obligatory. Unfortunately, the lack of standardization in methods and development of the correct formula for the balance sheet causes that the results are not very reliable and often incomparable. This approach can lead to improper verification of the results, the decline in profitability and inadequate assessment of the state of the environment. In Europe there are used about 45 different types of balances. They are used in the monitoring of surface and groundwater, air, forecasting changes in the environment, the impact of agriculture on natural ecosystems, to assess the economic aspects and for agri-environmental actions. Basically due to the nature of the farms, but also posed goals, balance sheets are divided into: partial - about selected areas of production, field scale - most commonly used in the protection of water quality, farms scale - dealing with farm as a specific ecosystem, system - used for detailed scientific considerations. Mostly, however, the literature meets mixed balance sheets or some modifications which are far deviating from the classical balance sheets. The balances are made also on different levels. Depending on the purpose of their preparation and needs the balance can be performed at the level of arable plots, fields area in farm, animal housing, reservoir (fish breeding ponds), farm, catchment rivers or lakes, administrative unit or country.
PL
Celem badań było określenie bilansu azotu, fosforu i potasu w płodozmianie ekologicznym na glebie lekkiej. Zmianowanie obejmowało następujące gatunki roślin rolniczych: ziemniak, owies, łubin żółty, żyto, facelia. Oprócz gatunków głównych uprawiano 3 gatunki roślin jako międzyplony: peluszka, gorczyca biała, seradela. Dodatkowo przed uprawą ziemniaka stosowano obornik w dawce 25 tźha-1. Obliczenia oparto o rzeczywiste dane uzyskanych plonów i zawartości składników w plonach. Bilans NPK sporządzono metodą ,,na powierzchni pola". W płodozmianie uzyskano dodatnie saldo bilansu azotu (+20,4 kg Nźha-1 rok-1)oraz nieznacznie ujemne salda fosforu (-3,1 kg Pźha-1 rok-1) i potasu (-4,5 kg Kźha-1 rok-1).
EN
The aim of this investigation was to determine balance of nitrogen, phosphorus and potassium in organic crop rotation system on light soil. The crop rotation comprised following agricultural plant species: potato, oat, yellow lupine, rye, phacelia. Apart from these main species 3 plants were cultivated as intercrop: field pea, white mustard, serradella. Before potato cultivation the manure in dose of 25 tźha-1 was applied. The calculations were based on real data of obtained yields and nutrients content in the yields. The ,,on surface of field" method was used in this investigation. In the crop rotation positive balance of nitrogen (+20,4 kg Nźha-1 per year-1) and slightly negative one for phosphorus (-3,1 kg Pźha-1 per year-1) and potassium (-4,5 kg Kźha-1 per year-1) were noted.
PL
Celem prowadzonych badań była ocena stopnia zrównoważenia gospodarki nawozowej w 20 wybranych gospodarstw ekologicznych, zlokalizowanych w województwie kujawsko-pomorskim. W ocenie zrównoważenia uwzględniono bilans NPK, udział zielonych pól oraz bilans glebowej substancji organicznej. Do sporządzenia bilansu składników mineralnych metodą "na powierzchni pola", wykorzystano program komputerowy Macrobil. Analizowane gospodarstwa ekologiczne charakteryzowały się dodatnim, bezpiecznym dla środowiska saldem bilansu azotu wynoszącym 2,8 kg N ha-1 rok-1. Natomiast saldo bilansu fosforu i potasu było ujemne i wynosiło odpowiednio:-2 i -21,6 kg ha-1 rok-1. Zrównoważony bilans potasu uzyskiwały gospodarstwa ukierunkowane na produkcję zwierzęcą, natomiast wyraźnie ujemny gospodarstwa specjalizujące się w produkcji roślinnej. Bilans glebowej substancji organicznej w badanych gospodarstwach ekologicznych był dodatni i wynosił średnio 0,53 t s.m./ha. Najwyższe wartości tego wskaźnika odnotowano w gospodarstwach wyspecjalizowanych w produkcji zwierzęcej. Udział pól zielonych w badanej grupie gospodarstw ekologicznych wynosił nieco ponad 50%, co wskazuje na duży ich potencjał w ograniczaniu niekorzystnych skutków towarzyszących produkcji rolniczej.
EN
Assessment of the sustainability of nutrient balances in selected group of 20 organic farms located in the Kujawsko-Pomorskie was aim of the research. Balance of NPK, the share of green fields and the balance of soil organic matter were taken into account in the assessment. MACROBIL program was used to calculate the field balance. Organic farms were characterized by a positive, safe balance of nitrogen of 2.8 N ha-1 year-1. While the balance of phosphorus and potassium was negative and amounted, respectively, -2 and -21.6 N ha-1 year-1. Sustainable balance of potassium was noted in the animal farms, while strongly negative in farms specialized in plant production. Balance of soil organic matter in the organic farms was positive and amounted on an average of 0.53 t DM/ha. The highest values of this index were recorded in farms specialized in animal production. The share of green fields in the studied group of organic farms amounted slightly more than 50%, which indicates their great potential in reducing the negative effects associated with agricultural production.
EN
Agricultural research on plant nutrition cannot be supported without results of long-term field experiments. The Central Institute for Supervising and Testing in Agriculture established four long-term field experiments in four experimental places of the sugar beet production region of the Czech Republic, in the years 1972–1979. Each experiment comprised 12 combinations of fertilization and had an eight years crop rotation. The following five combinations were used for evaluation of yields of sugar beet (roots and leaves) and quality of the products: the control treatment without fertilization, the treatment with farmyard manure (FYM) and three treatments with FYM applied together with comparative mineral fertilization at three different levels. In the control treatment, average yield of the main product (roots) was 52.0 tons×ha-1 with sugar content 18.5%. In the other treatments increase of fertilization caused gradual rising of the roots and leaves yield (for roots: from 57.5 to 68.3 tons×ha-1) and, on the other hand, the decrease of sugar content (from 18.6 to 16.8%). The nitrogen and potassium balances were negative, except for the highest level of mineral fertilization. The phosphorus balance was highly positive at all levels of mineral fertilization.
PL
Badania rolnicze nad odżywianiem roślin nie mogą rozwijać się bez wyników długoterminowych doświadczeń polowych. W latach 1972–1979, w Centralnym Instytucie Nadzoru i Badań w Rolni­ctwie założono cztery takie długoterminowe eksperymenty w czterech stacjach doświadczal­nych rejonu uprawy buraka cukrowego w Republice Czeskiej. Każde z doświadczeń obejmowało 12 kombinacji nawożenia i miało ośmioletni płodozmian. Następujące pięć kombinacji wykorzystano do oceny plonów buraka cukrowego (korzeni i liści) oraz jakości produktów: kontrolną — bez nawo­żenia, kombinację z obornikiem oraz trzy kombinacje (tzw. porównawcze) z obornikiem, uzupełnione trzema różnymi poziomami nawożenia mineralnego. W wariancie kontrolnym średni plon korzeni wyniósł 52,0 t×ha-1, przy zawartości cukru 18,5%. W pozostałych wariantach zwiększe­nie nawożenia spowodowało stopniowy wzrost plonów korzeni i liści (dla korzeni: od 57,5 t/ha do 68,3 t×ha-1), a z drugiej strony zmniejszenie zawartości cukru (z 18,6% do 16,8%). Bilans składników był negatywny dla azotu i potasu, z wyjątkiem kombinacji z najwyższą dawką nawożenia mineralnego. Bilans fosforu był wysoce pozytywny dla wszystkich poziomów nawożenia mineralnego.
EN
From the early 60's till the late 80's, in many countries - among them also in Hungary - agricultural production went through a tremendous development. In Hungary there was a 2-3-fold increase in the average yields of winter wheat, and maize - the two main crops - in comparison to those of the 50's. One of the main factors determining these developments was the increasing use of mineral fertilizers. From the turn of the century till the late 50's, nutrient balances in Hungary were strongly negative: 20 - 30 kg/ha/year less N and K₂O, and 10 kg/ha/year less P₂O₅ was given to the fields in the different forms (farmyard manure, mineral fertilizer and by-products, etc.), than was removed by the harvested yields. Nutrient balances of P became positive in the early 60's, while balances of N and K in the early 70's, resp. Then, for 20 years, N balances were positive by 10 - 20 kg/ha/year, while both P₂O₅ and K₂O balances by 30 - 50 kg/ha/year, resp. These long-term positive nutrient balances resulted in the NPK enrichment of our soils, which was also proven by the national soil test series. During the 80's, for example, the amount of yearly applied mineral fertilizer was 230 - 280 kg/ha N + P₂O₅ + K₂O/arable land. In certain regions N leaching could cause environmental damage, while, as a result of the P-Zn antagonism, on the fields poorly supplied with Zn, overfertilization with P resulted in 1 - 2 t/ha/year maize yield losses. From the early 90's, however, when political and ecological changes took place in the country, the free market was introduced, and state subsidies on mineral fertilizer were withdrawn, there was a sharp decrease in mineral fertilizer use: applied N dropped to 1/5th, P and K to 1/20th of the amount used in the 80's. This dramatic decrease resulted in the change of nutrient balances: in 1991 the balance for N was -60, for P₂O₅ -30, and for K₂O -40 kg/ha for the whole country, resp. In 1992 and 1993 the situation was similar, while in 1994 a slight increase in mineral fertilizer use was observed. According to our estimation, mineral fertilization of 150 kg/ha/year N + P₂O₅ + K₂O is sufficient for long-term sustainable plant nutrition in Hungary, if farmyard manure application and the incorporation of byproducts remains on the recent level. During intensive fertilization practice, emphasis was on the quantity, while crop and soil demands for specific or more economic fertilizers were not taken into consideration. For N, lime ammonium nitrate, for P superphosphate, and for K, potash chloride was used on almost the whole area. As a new attempt to find more economic P sources, Algerian rock phosphate was checked in field trials, set up on characteristic acidic soils in different regions of Hungary, as well as other Central European countries. The first two-year results are discussed in the presentation.
EN
The paper presents some current problems related to pig nutrition at the intensive and organic rearing systems. Issues shared by both sectors of the pig management as well as specific organic feeding regimes are discussed. A growing concern in nutrient balance has been emphasized, especially protein digested in the caudal segment of the small intestine. Besides, the problems of animal welfare in both management systems were addressed along with the ban on growth promoter application (hormones and antibiotics) that appear to be redundant or even hazardous for human health.
EN
The general impact of extra nitrogen on ecological stoichiometry was examined in alpine grasslands on the Tibetan Plateau. Extra nitrogen increased the ratio of nitrogen to phosphorus (N:P ratio) in leaves and aboveground parts of plants by 43.4% and 32.7%, respectively. In contrast, extra nitrogen reduced the ratio of carbon to nitrogen (C:N ratio) in leaves by 30.6%. Extra nitrogen decreased soil C:N ratio by 9.1% in alpine meadows, but increased soil C:N ratio by 3.4% in alpine steppes. Extra urea had a stronger positive impact on aboveground vegetation N:P ratio than did extra ammonium nitrate. Extra urea rather than ammonium nitrate decreased aboveground vegetation C:N ratio and soil C:N ratio. The impact of extra nitrogen on aboveground vegetation N:P ratio was positively correlated with latitude, mean annual temperature and precipitation, nitrogen application rate and accumulated amount, but negatively correlated with elevation, duration and aboveground vegetation N:P ratio of the control plots. The impact of extra nitrogen on leaves N:P ratio was positively correlated with nitrogen application rate and accumulated amount. The impact of extra nitrogen on leaves C:N ratio was positively correlated with latitude, but negatively correlated with mean annual temperature and precipitation, nitrogen application rate, accumulated amount, duration and leaves C:N ratio of the control plots. Therefore, nitrogen enrichment caused by human activities will most likely alter element balance and alpine plants from nitrogen limitation to phosphorus limitation. This effect may weaken with time, and increase with climatic warming, increased precipitation and nitrogen input rate.
first rewind previous Strona / 2 next fast forward last
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.