Organinės anglies sekvestracijos galimybės sunkaus priemolio dirvožemyje taikant supaprastintą žemės dirbimą

 &nbsp

Soil carbon, nitrogen and phosphorus distribution in grassland systems, important for landscape and environment

The accumulation of organic carbon (SOC), nitrogen (N) and phosphorus (P) in the soils of protected areas and agrarian lands in Central Lithuania was assessed. Wood pasture is recognised as an important but now scarce element of the historic environment still evident in the current landscape. Soil pH was lower in the surviving wood pasture compared to the pasture under restoration, and pH of the old semi-natural pasture and organically grown legume sward soils was close to neutral. The highest SOC content was accumulated in the meadows of pre-mainland section of floodplain of the Nevėžis. It was more than 5 times as high as that in agrarian land grown with swards, and higher than that accumulated in semi-natural pasture and wood pasture. Soils of the protected areas of pre-mainland section were characterized by the largest amount of N. Soils of semi-natural pasture, affected by agricultural management, and meadows of pre-mainland section were found to be the highest in the total P content. Due to the differences in agricultural management, diverse plant communities are developing in the central section of floodplain of the middle reaches of the Nevėžis

Soil Organic Matter under Different Soil Management

Our investigation was aimed to assess impact of different intensity tillage systems, straw and green manure combinations on soil organic matter quantity and quality. The data based on long-term field experiment established since 1999 in the Experimental Station of the Aleksandras Stulginskis University, Kaunas district at 54°52'50 N latitude and 23°49'41 E longitude. The soil of the experiment site is Endohypogleyi-Eutnc Planosol. The obtained results after 14 years from the beginning of field experiment indicated a positive effect on soil organic carbon (SOC) in plots where straw were incorporation or minimized tillage. Significantly highest amount of SOC (2.39 %) was obtained in topsoil layer (0-10 cm depth) after straw chopped and spread at harvesting. In comparison, the lowest content of SOC (2.13 %) was found in soil where straw was removed. The mobile humus susbstances depends on tillage practise, straw and green manure management and were different among treatment. Analysing the straw effect on the content of mobile humus susbstances in toplayer (0-20 cm) the higher amount (7.52 C g kg" i mobile humus substances was found on treatment with straw. Tillage systems had no significant effect on mobile humic acids but tended to increase SOM quality. Mobile humic acids in treatments with conventional ploughing, shallow ploughing, shallow loosening without straw amounted 35.5-37.7 % or with straw - 42.3- 43.6 % from total amount of labile humus substances. The different tillage systems had positive impact on soil organic carbon poc.; in 0-10 cm soil layer. The shallow loosening (32.7 Mg ha"1), green manure incorporation (35.9 Mg ha"1) and no-tillage (35.9 Mg ha"1) significantly increased poo J to compare with conventional deep ploughing (25.5 Mg ha"1). Shallow ploughing and shallow loosening have no effectLietuvos agrarinių ir miškų mokslų centro filialas Žemdirbystės institutasVytauto Didžiojo universitetasŽemės ūkio akademij

The assessment of Virginia mallow (Sida hermaphrodita Rusby) and cup plant (Silphium perfoliatum L.) productivity, physico-mechanical properties and energy expenses

Field and laboratory trials of the energy crop species Virginia mallow (Sida hermaphrodita L. Rusby) and cup plant (Silphium perfoliatum L.) were conducted to evaluate the effects of liming and nitrogen application on biomass and energy productivity and the suitability of the biomass for biofuel production. Independent of the growing year, the average DM (dry mass) yields of cup plant and Virginia mallow ranged from 6746 kg ha−1 to 13,485 kg ha−1 and from 4675 kg ha−1 to 7451 kg ha−1, respectively. The Virginia mallow and cup plant pellet humidity ranged from 9.6% to 11.6%, and the Virginia mallow pellet density reached 969.3 kg m−3 DM. The ash contents of the Virginia mallow and cup plant pellet were high, reaching 10% and 6.1%, respectively. The net calorific values of the Virginia mallow and cup plant dry masses were 17.49–18.44 kJ ha−1 and 17.19 to 17.48 kJ kg−1, respectively, and were correlated with the biomass crude fibre content with energy outputs of 79–105 GJ ha−1 (for Virginia mallow) and 200–236 GJ ha−1 (for cup plant). The energy expenses of the Virginia mallow and cup plant growing methods (including planting and harvesting year) reached 8630–29,264 MJ ha−1Lietuvos agrarinių ir miškų mokslų centro Vėžaičių filialasLietuvos agrarinių ir miškų mokslų centro filialas Žemdirbystės institutasVytauto Didžiojo universitetasŽemės ūkio akademij

Daugiamečių miglinių žolių ir pavėsinių kiečių biomasė termocheminei konversijai

Lietuvos agrarinių ir miškų mokslų centro filialas Žemdirbystės institutasLietuvos agrarinių ir miškų mokslų centro filialas žemdirbystės institutasVytauto Didžiojo universitetasŽemės ūkio akademij

Artemisia dubia augimas, derlius ir biomasės tinkamumas deginti

e-ISSN 2335-8947Daugelyje šiauresnių šalių padidėjo susidomėjimas žemės ūkio augalų biomasės naudojimu energijos tikslais, o tvariam naudojimui reikalingi kuo didesnio derlingumo ir tinkamos kokybės nauji augalai. Tyrimo tikslas – nustatyti Artemisia dubia Wall. biomasės derlių auginant vidutinio klimato sąlygomis ir biomasės savybes deginant. Augalai auginti giliau karbonatingame sekliai glėjiškame rudžemyje (RDg8-k2) netręšiant ir tręšiant mineralinėmis azoto trąšomis 90 ir 170 kg ha-1 N. Augalų augimas, derlius ir deginimui svarbios biomasės savybės vertinta antraisiais ir trečiaisiais augalų auginimo metais. Azoto trąšos šiek tiek didino augalų aukštį ir biomasės kaupimą, tačiau drėgmės kiekis biomasėje mažėjo lėčiau. Tręšiant azotu augalų biomasės antrųjų ar trečiųjų auginimo metų metinio derliaus esminio padidėjimo negauta, tačiau ir be tręšimo azotu gautas 15,8 iki 17,1 t ha-1 sausųjų medžiagų derlius lenkia vidutinius kitų augalų biomasės derlius. Tręšimas azotu esmingai didino azoto ir lignino kiekius biomasėje. Nepriklausomai nuo tręšimo, degimo proceso svarbių cheminių elementų anglies ir sieros vertės biomasėje kito nežymiai. Augalų netręšiant gautas gana nedidelis kiekis pelenų, o šilumingumas siekė 18,5 MJ kg-1. Siekiant išsamiau įvertinti daugiamečių kiečių biomasės derlių bei kokybinės sudėties vertes ir tręšimo įtaką, reikia papildomų tyrimųIn recent years, there has been increasing interest in the use of agricultural biomass for energy purpose in many northern countries. This has created demand for novel, high biomass yielding, specific quality crops for sustainable use. The aim of the current study was to examine Artemisia dubia Wall. for biomass yield and biomass characteristics important for combustion in the temperate climate conditions. The crops were grown on an Endocalcari- Epihypogleyic Cambisol (CMg-p-w-can) without fertilization and with mineral nitrogen fertilization at 90 and 170 kg ha-1 N rates. Nitrogen fertilization slightly increased plant height and accumulation of biomass. Moisture content in the biomass of swards applied with a higher rate of mineral N decreased more slowly compared with the lower rate. Biomass annual yield in the second and third years ranged from 15.8 to 17.1 t ha-1; however, significant effect of nitrogen fertilization was not observed. Nitrogen fertilization had a significant influence on N content and lignin in the biomass. The variation of values of the elements relevant for combustion (carbon and sulphur) in the biomass was negligibly influenced by nitrogen fertilization. The relatively low ash content and heating value, amounting to 8.5 MJ kg-1 achieved even without nitrogen fertilization, makes A. dubia a promising energy crop in the northern part of the temperate climate zone. More studies and analyses on A. dubia are needed to ascertain the fertilization effect on biomass yield, biomass quality and biomass properties for combustion in senescent plantsLietuvos agrarinių ir miškų mokslų centrasVytauto Didžiojo universitetasŽemės ūkio akademij

Paprastojo kiečio (Artemisia vulgaris L.) bei geltonžiedžio legėsto (Silphium perfoliatum L.) produktyvumo ir kietojo kuro ruošimo technologinis vertinimas

Tyrimai atlikti siekiant nustatyti dirvožemio pH (arba kalkinimo) ir tręšimo azoto trąšomis įtaką paprastojo kiečio (Artemisia vulgaris L.) ir geltonžiedio legėsto (Silphium perfoliatum L.) sausosios masės (SM) derliui, šilumingumui ir mechaninėms savybėms. Lauko bandymai įrengti 2008 m. Vakarų Lietuvoje, natūraliai rūgščiame (pH 4,2–4,4) moreniniame priemolyje. Remiantis vidutiniais ketverių metų tyrimų duomenimis, kiečių didžiausias SM derlius buvo nustatytas 2009 m. – 4100 kg ha-1, kuris esmingai sumažėjo vėlesniais tyrimų metais, o legėstų didžiausias SM derlius buvo gautas 2011 m. – vidutiniškai 17980 kg ha-1. Dirvožemio pH padidėjimas nuo 4,2–4,4 iki 5,6–5,7 (pakalkinus 6,0 t ha-1 CaCO3) legėstų SM prieaugį padidino 27,4 %. 120 kg ha-1 N trąšų panaudojimas iš esmės padidino bendrą kiečių ir legėstų SM derlių – atitinkamai 34,5 ir 26,7 % daugiau nei netręšiant. Tirta paprastųjų kiečių ir geltonžiedžių legėstų smulkinimo kokybė bei pjaustinio frakcinė sudėtis pagal Europos Sąjungos šalyse taikomą metodiką, naudojant sietus su skirtingo skersmens skylutėmis. Nustatyta, kad geltonžiedžių legėstų pjaustinys buvo smulkesnis ir tolygesnis, labiau tinkantis naudoti energetinėms reikmėms. Vertinant tirtų augalų malimo kokybę nustatyta, kad geltonžiedžių legėstų miltų dalelės buvo smulkesnės ir tolygesnės, todėl šie augalai labiau tinka presuoti ir naudoti deginimui. Didžiausias vidutinis paprastųjų kiečių biomasės šilumingumas siekė 17,97 MJ kg-1 (2010 m.), o geltonžiedžių legėstų – 17,48 MJ kg-1 (2012 m.). Abiejų augalų šilumingumo reikšmėms didžiausią įtaką turėjo augimo metai ir 120 kg ha-1 azoto trąšų panaudojimasThe research was carried out to determine the effects of soil pH (or liming) and nitrogen (N) fertilization on the common mugwort (Artemisia vulgaris L.) and cup plant (Silphium perfoliatium L.) dry mass (DM) yield, calorific value and mechanical properties. Field experiments were set up in 2008 in Western Lithuania on a naturally acid (pH 4.2–4.4) moraine loam. According to the averaged data of four experimental years, the highest DM yield 4100 kg ha-1 of common mugwort was established in 2009, which significantly decreased in the subsequent years. And, conversely, the highest cup plant DM yield 17980 kg ha-1 was obtained in 2011. An increase in soil pH from 4.2–4.4 up to 5.6–5.7, resulting from 6.0 t ha-1 CaCO3 application, increased cup plant DM yield by 27.4%. Fertilization with 120 kg ha-1 N significantly increased common mugwort and cup plant DM yield by 34.5% and 26.7% respectively, compared with the treatment without N fertilization. We also studied the chopping quality of common mugwort and cup plant and chaff fractional composition using sieves with different mesh sizes. The chaff of cup plant was finer and more even, and thus more suitable for use for energy purposes. Plant milling quality showed cup plant particles to be smaller and more even too, and thus better suited for pressing and combustion. The highest calorific value of common mugwort (17.97 MJ kg-1) was obtained in 2010 and that of cup plant (17.48 MJ kg-1) in 2012. The calorific values of common mugwort and cup plant were influenced most by the year of cultivation and 120 kg ha-1 N applicationVytauto Didžiojo universitetasŽemės ūkio akademij

Artemisia Dubia Wall. – A Novel Energy Crop for Temperate Climate Zone in Europe

In most northern countries the increased interest in the use of agricultural biomass for any energy purpose and novel crops with as high as possible yield of appropriate quality are required for sustainable cultivation. The aim of the study was to evaluate the productivity, chemical composition, drying parameters at Artemisia dubia Wall, in the temperate climate conditions. A. dubia was investigated on an Endocalcari-Epihypogleyic Cambisol. Three treatments (not fertilized, fertilized with mineral nitrogen fertilizers Nto and Ni») were replicated four times. Biomass yield, chemical composition and drying parameters were evaluated. Nitrogen fertilizers slightly increased plant height, but significant effect was not observed. The highest yield of A. dubia biomass was produced in the swards with mineral nitrogen fertilization at: a rate of 170 kg N ha."1 and had a significant influence on N content in A.duhia biomass. The values of important elements for combustion properties such as carbon and sulphur in the biomass varied little with or without N-lerfilizers. The moisture content of the biomass obtained at harvest time could be decreased to a safe moisture content by using ventilation. More studies and analyses on A.duhia are needed to ascertain the fertilization effect on biomass yield, biomass quality and biomass properties for combustionLietuvos agrarinių ir miškų mokslų centrasVytauto Didžiojo universitetasŽemės ūkio akademij

The effects of agrogenic transformation on soil profile morphology, organic carbon and physico-chemical properties in Retisols of Western Lithuania

The aim of this study was to determine changes in the morphological, physical and chemical properties of Retisols caused by their agrogenic transformation. The study carried out on Retisols on relatively natural and agrogenically affected land in 2016. Soil samples taken from the genetic horizons of all profiles to measure soil organic carbon, pH, hydromorphic and physical properties. Due to long-term, deep ploughing, the sequence of soil horizons in the Retisol profile had changed from O– Ah–El–ElBt to Ahp–ElBt. Intensive soil liming changed chemical properties and morphological features of Retisol. The clay and silt particles leached out of from the Ah and El horizons to the deeper layers due to illuviation and podsolization. The content of SOC in the 0–30 cm layer of the Ah horizon of agrogenically affected Retisol was 1.0%, and in the forest Retisol – 1.7%; however, forest Retisol was more acidic. Ploughing and no tillage management caused a reduction in total porosity, water holding capacity and plant available water content compared with the other land-uses. We conclude that the use of ploughless tillage on Retisol is not identical to the conditions of natural soil formation and soil fertility maintenanceLietuvos agrarinių ir miškų mokslų centro filialas Žemdirbystės institutasLietuvos agrarinių ir miškų mokslų centro Žemdirbystės institutasVytauto Didžiojo universitetasŽemės ūkio akademij