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The main goal of this study was to investigate the effect of biochar on hygroscopic water content (maximum hygroscopicity) of grey-brown podzolic soil (Haplic Luvisol). The biochar was applied to the soil of sub-plots under fallow and grassland in the amount of 0 (control), 10, 20 and 30 Mg·haˉ¹. Soil samples were taken three times per year during the period of 2013-2015. Sorption isotherms of water vapour were determined for all studied samples and the maximum hygroscopicity (MH) was calculated from the relative water vapour pressure at p·p0ˉ¹ = 0.965. Value of the MH varied from 1.5 to 3%. The effect of biochar addition to soil on hygroscopic water content was ambiguous. Addition of biochar caused a slight decrease in MH value in the case of the grassland. For the fallow, a positive effect of biochar addition was observed.
Remote sensing methods, including aerial photography and satellite images, could be successfully used for detecting and acreage assessing of landscape components like fallow fields. The objective of the present study was to characterize the reflectance of fallow fields situated in various soil conditions and of different age and compare them with spectral characteristics of main arable crops: winter rye, spring oat, winter oilseed rape, corn, potatoes and meadow. Field spectral reflectance measurements were made with the CIMEL CE313 luminancemeter and five vegetation indices (NDVI, STVI, MSI, MNDVI and GRVI) were developed by combining the reflectance factors in the five wavebands (450, 550, 650, 850 and 1650 nm). In the second part of May, when seasonal biomass peak of winter crops and meadows occurs and spring crops partly covers the soil, significant differences were observed in the spectral properties of fallow and cultivated fields. Results showed that among the analyzed vegetation indices MSI index (R₁₆₅₀/ R₈₅₀) was found to be the best for discriminating among the fallow fields and GRVI (R₅₅₀/R₆₅₀) and NDVI ((R₈₅₀–R₆₅₀)/(R₈₅₀+R₆₅₀)), were the best discriminators between the fallow fields and arable crops.
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The object of investigations were mountain soils derived from various parent rocks which were fallowed during five and ten years, in comparison to arable soils. The aim of the research was to characterise physical properties of the fallows and adjoining arable fields. The obtained results point to higher values of porosity, bulk density as well as content of total carbon of fallows in comparison to arable soils. On the analysed fallows far higher growth of weed with high contribution of many-year species was found,
In spring 1996, four types of fallows were established on good wheat complex soil (classified as IIIa in the Polish soil classification system): sown with oriental goat’s rue (Galega orientalis, Lam.), traditional fallow, seeded with a mixture of oriental goat’s rue (Galega orientalis Lam) and smooth brome (Bromus inermis) and under smooth brome (Bromus inermis). This paper documents the results obtained in 2000-2004. Plant samples (4 x 1 m2) were taken from the fallows once every year at the same plant growth and development stage. The content of macroelements in the plant material was determined using conventional methods. The statistical elaboration of the results was based on the analysis of regression and correlation. The results proved that fallow under perennial plants is superior in activating and cycling nutrients to traditional fallow, overgrown with wild plants. On the other hand, when fallow soil is covered exclusively with a papilonaceous plant (e.g. oriental goat’s rue), it is more likely to experience transfer of nitrates (V) to ground waters. A good solution to this problem could be sowing fields which are set aside as fallows sown with a mixture of oriental goat’s rue and smooth brome. Soil protected by these two plants remains fertile and does not create an ecological risk caused by migrating N-NO3.
Studies on the soil seed banks of fallow lands of different ages were carried out on poor soil abandoned fields and in a fresh coniferous forest in north-eastern Poland. The size and diversity of seed banks was studied with the seedling emergence method. Species abundance (i), density (ii), number of species from different biological groups (iii) and distribution and mean LI value (iv) were analysed as the function of fallow land age. It was found that: (i) species diversity, number of species and ln of density are linear declining function of the fallow land age; (ii) for approx. 25 years the share of diaspores of identified species groups has been relatively similar. Seed banks of 40-50-year-old fallow lands are dominated by Calluna vulgaris, while the seed bank of the old fresh coniferous forest is dominated by dicotyledonous perennials and grasses; (iii) within the first 50 years of succession the persistence of seed banks measured by the Longevity Index increases gradually.
The aim of this work was to ascertain the levels of some selected chemical and physico-chemical properties in the fallow soils and in the neighbouring fields under cultivation. The studied fields were located on heavy brown fen soil, uncultivated for 4 and 8 years and rusty soil that lay fallow for 8 years. Fallow soils, in comparison to arable soils, were characterized by a lower content of organic carbon and available potassium forms as well as phosphorus and magnesium. .Changes in the properties of arable soils under cultivation and the soils allowed to lie fallow were much clearer in the clay soils (heavy fen soil) than in sandy rusty soils. Humus horizon in the 8-year fallow clay soil was characterized by an increased hydrolytic acidity and decreased exchangeable calcium level in the sorption complex.
Interactions between members of microfungal communities of three arable and two fallow land soils and three P strains of Heterobasidion annosum were investigated in vitro. The effect of soil fungi on the pathogen was evaluated with two methods. In the first, the mycelial growth of H. annosum strains was measured and the experimental data were analysed using statistics. In the second, the biotic series method was used. The differences between the effects of soil fungi dominating in arable and fallow land soils were statistically significant. The microfungal communities of fallow land soils inhibited the growth of the pathogen more than those inhabiting arable soils. Evaluation of suppressive effect of the soil fungi on the pathogen with biotic series method showed also far more negative influence of microfungal communities of fallow land soils on the growth of H. annosum strains. Considering the positive effect of chemical and biological properties of the fallow land soils on the growth of Scots pine and highly suppressive effect of microfungal communities of these soils on the growth of H. annosum observed in the presented study, it may be concluded that arable soils left barren for many years are more beneficial for establishing of Scots pine plantations than cultivated soils.
The investigations were carried out in the years 2000- -2004 on permanent grassland in Czarny Potok (Beskidy Mts.- 650 a. s. 1.). Botanical census was conducted by using Klapp’s method on 26 plots (18 random selected plots and 8 controls). The whole floristic material was subjected to numerical classification. As a result, three main types of plots with the dominating species of: Juncus effusus (1), Cirsium arvense (2) and Deschampsia caespitosa (3), were distinguished. Poa trivialis was the dominating species of the control plots. Results of the floristic and habitat analysis confirmed that the main factors determining the formation of meadow and pasture communities are as follows: the method of use, water relations and soil nutrient availability. It was found that idle glades are characterised by degraded sward of the average (the sward patches with the domination of Deschampsia caespitosa) or low use value (the swards patches with the domination of Cirsium arvense and Juncus effusus). The deterioration of the feeding value of the fallow plots is an effect of their high weed infestation, which in turn results, in this case, from habitat changes as a consequence of the cessation of use and earlier errors made in cultivation measures. Both high and low soil moisture, with improper meadow management, accelerated the weed infestation of the sward, what in turn lowers its use value. Cutting and fertilisation positively affect the use value of plant habitats, what was confirmed by the botanical and habitat analysis of the control plots with the domination of Poa trivialis, which is known to be of good use value.
Since 1990 in Poland, a lot of soils have been changed to fallow.At first, degraded soils from eroded areas were changed. Some of them are fallow till today.Research work was carried out on the erroded soils that were under intense agricultural use in the 80-ties.Investigations on the superficial layer of these soils were carried out in 1995, after a four-year periodof fallow conditions. The investigations concentrated on the changes in chemical properties of the humus horizon (0 - 20cm) and changes of biological activity (0-40 cm) formed during the fallow period.The range of changes in the chemical properties was not big.However, biological activity of these soils changed more substantially. A decrease of C organic content was also characteristics. The present authors determined also a decrease of hydrolytic acidity in some soils, according to their location in the relief. In some soils, the content of Mg and K available forms was higher. Some of the soil functions related to habitation were changed too, e.g. visible forms of water erosion stopped.
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Studies on flora of fallow lands of the Podlaski Przełom Bugu mesoregion were carried out between 2001 and 2003 in the area of 77 localities, situated in 20 communes. A systematic list of fallow land flora was made and its variation with respect to occurrence frequency, biological spectrum, persistence and belonging to geographic-historical and sociological-ecological groups was analyzed. Flora of fallow lands of the Podlaski Przełom Bugu mesoregion includes 442 species included in 60 families and 241 botanical genera. The most numerous group comprises very rare, rare and quite frequent species. In the floristic composition of the analysed flora, apophytes (72.2%) predominate over anthropophytes (2.8%) as well as perennials (61%) over ephemerals (39%). Considering the biological spectrum of flora, hemicryptophytes (49%) and terophytes (32%) predominate over other life forms. Forest and shrub species (18.5%) as well as meadow (17%) and xerothermic sward plants (17.4%) have the largest share in the flora. The abundant occurrence of segetal (15.8%) and long-lived ruderal communities (8.1%) was also noted. Moreover, the occurrence of 25 species endangered with extinction in fallow land communities of the Południowopodlaska Lowland was noted. They are as follows: Nigella arvensis, Potentilla recta, Platanthera chlorantha, Agrostemma githago, Prunella grandiflora, Populus alba, Silene tatarica, Papaver argemone, Papaver rhoeas, Veronica polita, Hieracium floribundum, Bromus secalinus, Polygonum bistorta, Geum alleppicu, Astragalus arenarius, Centaurium erythraea, Veronica agrestis, Veronica verna, Cirsium rivulare. Allium oleraceum, Hierochloë odorata, Chenopodium polyspermum, Vinca minor, Dipsacus silvestris and Campanula latifolia.
The studies of fallow lands were undertaken on the Przemyśl hills in the area of Cisowa locality which, till very recently, have been owned by a State Farm (PGR). The objective was to gain insight into the composition and diversification of plant communities on meadows, pastures and fields laid fallow, in context of habitat conditions prevailing after the use had ceased. The study utilised an old cadastral map showing the type of communities by category of use: meadows, pasture, and cultivated fields. The study material consisted of 180 relevés, obtained in the period 1998-2000 using the Braun-Blanquet method. By employing numerical classification, eight plant communities were distinguished, including only two of the association rank: Epilobio-Juncetum effusi, Arrhenatheretum elatioris. The analysis of Ellenberg’s habitat indices proved that all the communities belonged to the half-light vegetation group, occurring mostly on fresh soils, under intermediate moisture-content conditions, more rarely on moist soils which do not dry out. The soil reaction was most often neutral or slightly acidic, and in most of the soils the nitrogen content was in the intermediate range. The two principal trends in the succession of communities in the area, after its farming management has ceased, are: marked increase in species richness resulting from the expansion of species, and the process of overgrowing by woody vegetation.
Opracowanie przedstawia wyniki badań nad całkowitym bilansem promieniowania Q* i jego składowymi nad dwiema powierzchniami rolniczymi: porośniętą trawą Q*tr i powierzchnią bez roślin Q*ug prowadzonych w Obserwatorium Wrocław-Swojec. Wykorzystano 12-miesięczny materiał pomiarowy z 2008 roku z ciągłej rejestracji gęstości strumienia całkowitego promieniowania słonecznego K↓, gęstości strumienia promieniowania odbitego od powierzchni trawy i ugoru K↑, gęstości strumienia promieniowania zwrotnego atmosfery L↓ i gęstości strumienia promieniowania powierzchni bez roślin i porośniętej trawą L↑. Skoncentrowano się na ukazaniu różnic pomiędzy wartościami radiacyjnymi tych powierzchni. Rozpatrzono przyczyny różnic w średnich wartościach miesięcznych bilansu promieniowania w przebiegu dobowym i rocznym. Zanotowano przewagę bilansu promieniowania powierzchni trawy Q*tr nad ugorem Q*ug w okresie od V-VIII. W pozostałych miesiącach powierzchnia bez roślin (ugór) miała wyższe wartości salda promieniowania, lecz nie równoważyły one ilości energii zmagazynowanej przez powierzchnię trawiastą w okresie letnim. Zadecydowało to o wyższych średnich rocznych wartościach Q*tr nad odpowiednimi wartościami Q*ug. Podstawowym regulatorem zmian różnic bilansu obu powierzchni była zmiana albedo i różnice w wypromieniowaniu strumienia L↑. Rozważono topoklimatyczne skutki zaobserwowanych różnic radiacyjnych.
Frakcja akumulowanej energii fotosyntetycznie czynnej (fAPARcanopy) jest ważnym parametrem ekofizjologicznym, stosowanym między innymi do szacowania produkcji pierwotnej brutto (GPP) ekosystemów. W pracy przedstawiono zależności pomiędzy dobową zmiennością frakcji akumulowanej energii fotosyntetycznie czynnej a dwoma spektralnymi wskaźnikami roślinności – znormalizowanym różnicowym wskaźnikiem wegetacji (ang. Normalized Difference Vegetation Index, NDVI) i wskaźnikiem odbicia fotochemicznego (ang. Photochemical Reflectance Index, PRI). Pomiary wykonano 28 maja 2012 r. na poletkach eksperymentalnych z uprawami jęczmienia jarego, żyta ozimego i pszenicy ozimej oraz na poletku wieloletniego odłogu. Pomiary padającego, przepuszczonego i odbitego promieniowania w zakresie PAR (potrzebne do obliczenia fAPARcanopy) wykonano z wykorzystaniem systemu pomiarowego firmy Delta-T (Delta-T Devices, Cambridge, UK). Potrzebne do obliczenia NDVI i PRI pomiary promieniowania padającego i odbitego o długościach fali 530, 570, 670 i 849 nm wykonano używając dwóch czterokanałowych czujników SKR1850 (SKYE Instruments Ltd., Llandrindod Wells, UK), zamontowanych w pozycji zenit – nadir na przenośnym urządzeniu SpectroSense2+. Z zaprezentowanych danych wynika, że NDVI stanowi znacznie lepszy niż PRI spektralny wskaźnik dobowej zmienności fAPARcanopy roślin uprawnych. Uzyskane wyniki świadczą o tym, że fAPARcanopy nie jest jedynym czynnikiem kształtującym zmienne wartości wskaźników NDVI i PRI w cyklu dobowym.
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