Ograniczanie wyników

Preferencje help
Widoczny [Schowaj] Abstrakt
Liczba wyników

Znaleziono wyników: 45

Liczba wyników na stronie
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 3 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników

Wyniki wyszukiwania

Wyszukiwano:
w słowach kluczowych:  soil science
help Sortuj według:

help Ogranicz wyniki do:
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 3 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników
The paper presents a digital valorisation of soil trophism based on easily accessible properties. This method results from a soil skeleton, silt and clay part percentage share, reaction, base exchangeable cations sum and the organic matter decomposition rate. The above-mentioned properties have been assigned numbers from 1 to 10 but soil skeleton from 0 to 5 in proposed ranges. Totals of the above numbers decreased of soil skeleton index and calculated weighed means in profile constitute Forest Soil Trophism Index (ITGL). This method serves soils trophism valorisation as well as soil and forest sites classification.
For several years now the Polish Normalisation Committee (PKN) has been angaged in the process of introduction (and implementation) of international standards complying with the Internationsl Standard Organsation (ISO) into the set of of Polish Standards.At present, in the PKN Commission of Soil Physics, a number of such standards are being prepared (translated) -including a very comprehensive standard dealing with partiele size distribution determination in soil material-ISO 11277 [6], Some principles and requirements included in this standard differ significantly from those commonly accepted and widely in use now in numerous pedologie laboratories in Poland [7,8]. Below there are some of the most important differences: (1 ) the requirement to remove organic matter from test samples (using 30% v/v solution of H2O2), (2) the requirement to remove water soluble salts and gypsum (to electrical conductivity 0,4 dS/m), (3) sample dispersion process must be longer than 18 hours. Many other requirements, of relatively lesser importance, in many cases also do not correlate with those commonly accepted in our laboratories.
The author points to the necessity of propagating knowledge on the soil and suggests ways to do it. Firstly, he emphasises shortage of didactic aids for comprehensive teaching of soil science. He discusses this problem in comparison to other natural sciences far better known. As there are no useful teaching aids, the author draws our attention to the importance of the soil monolith, soil displays, posters and atlases. Moreover, he emphasises the role of Internet in education. Finally, he proposes to found a soil profile museum for educational purposes.
Commonly used gravimetric; method of determining soil density was compared under laboratory conditions with the indicator method developed at the Department of Soil Cultivation and Fertilization Techniques, IUNG Jelcz-Laskowice. The tests were carried out on artificial soil profiles with four degrees of compaction. Differences in the soil density determined with respective methods were in most eases contained within the limits of the measurement error. Discrepancies of the results obtained with the methods compared were decreasing along an increasing degree of soil density and thickness of the layer measured. The results obtained encourage to acknowledge the indicator method tested as an applicable measuring device lbr the density dynamics of soil profile.
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 3 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.