The influence of primary soil tillage on soil weed seed bank and weed incidence in a cereal-grass crop rotation

Abstract A field experiment was carried out at Vėžaičiai Branch of Lithuanian Research Centre for Agriculture and Forestry during the period 2008-2011. The study was aimed to determine the effects of various soil tillage methods: deep ploughing (20-25 cm), shallow ploughing (10-12 cm), shallow ploughless tillage (8-10 cm) and soil fertility improvement measures (plant residues, plant residues + straw, green manure 1 st cut + straw, green manure 2 nd cut + straw, farmyard manure 40 t ha -1 + straw) on the soil weed seed bank and weed incidence in a cereal-grass crop rotation. The soil of the experimental site is Dystric-Epihypogleyic Albeluvisol (ABg-p-w-dy) with a texture of sandy loam. In all experimental years, primary soil tillage had a significant influence on weed incidence in the crops of the rotation and on soil weed seed bank. The greatest amount of weeds, both in numbers and dry mass, in the crops of winter triticale and spring rape was determined in the shallow ploughless tillage treatment, in the crops of spring barley in the shallow ploughing treatment, and in the sward of red clover in deep and shallow ploughing treatments. All soil fertility improvement measures and their interaction with soil tillage methods did not have any substantial influence on the weed incidence in the rotation crops. The soil weed seed bank was 1.5 and 2.2 times greater in the shallow ploughing and shallow ploughless tillage treatments, compared with the conventional tillage treatment (deep ploughing). The influence of soil tillage methods manifested itself not only directly, but also through its interaction with soil fertility improvement measures. Regardless of the chosen soil fertility improvement measure, in all the treatments of shallow ploughless tillage, the soil weed seed bank was significantly greater, compared with the conventional soil tillage treatments. In the shallow ploughing and shallow ploughless tillage treatments there were found 25.5% and 41.5% more weed seed species in the soil, compared with the conventional tillage treatment. The seeds of Chenopodium album L., Persicaria lapathifolia L., Fallopia convolvulus L. and Viola arvensis Murray were found in all tillage treatments. The distribution of F. convolvulus L., P. lapathifolia L. seeds was significantly influenced by soil tillage only, that of V. arvensis Murray by soil tillage and its interaction with soil fertility improvement measures, and that of Ch. album L. by soil fertility improvement measures only

The impact of chemical additives on the process of biodegradation of oil products /

Many modern technologies for treatment of soil polluted with oil products are developed through creation of new and efficient bio-agents that help to degrade oil products. Another trend in development of new technologies aims to speed up the growth of soil microorganisms, this way accelerating biodegradation of oil products without the help of introduced microorganisms. The biodegradation of diesel fuel and heavy fuel oil was tested in the soil using chemical additives (oxidizing agents). The tests aimed to ascertain the impact of H2O2, KMnO4 and MnSO4 on residual concentrations of heavy fuel oil and diesel fuel, and the total number of microorganism colonies, as well as the number of oil-oxidizing microorganism colonies in the soil. After the statistical analysis of the data obtained during the experiment, a statistically significant (p <0.05) difference between control samples and samples with introduced chemical additives was obtained both in the soil contaminated with heavy fuel oil and diesel fuel. It was determined that use of KMnO4 as an oxidizing agent in the soil contaminated with heavy fuel oil, resulted in 3 times less statistically significant residual value of the heavy fuel oil concentration than in the control samples; however, no statistically significant difference was found between oxidizing agents (potassium permanganate and hydrogen peroxide). In cases where soil is contaminated with diesel fuel, there is a significant difference between KMnO4 and H2O2, which shows that potassium permanganate has a bigger impact on the degradation of diesel fuel than hydrogen peroxide. The residual concentration of diesel fuel in the samples with KMnO4 was 3 times less statistically significant than in the samples with H2O2, and 5 times less than in the control samples. The use of both – KMnO4 and MnSO4 – created more favourable conditions for biodegradation of diesel fuel and heavy fuel oil in the soil. A positive growth of microorganisms using Mn of different valence was observed during the entire course of experiment. Various chemical additives could be used in the technological process of biotreatment, when soil is contaminated with oil products. Santrauka Daugelis šiuolaikinių užteršto naftos produktais dirvožemio valymo technologijų vystosi kurdamos naujus ir efektyvius, naftos produktus skaidančius bioagentus. Kita naujų technologijų vystymosi kryptis – neįnešant mikroorganizmų, pagreitinti dirvožemyje jau esančių mikroorganizmų vystymąsi, paspartinant naftos produktų biodegradaciją. Dyzelino ir mazuto biodegracija buvo tirta dirvožemyje, naudojant cheminius priedus (oksidatorius). Buvo tirta H2O2, KMnO4 ir MnSO4 įtaka mazuto ir dyzelino liekamosioms koncentracijoms, bendram ir naftą oksiduojančių mikroorganizmų skaičiui dirvožemyje. Atlikus statistinę eksperimento metu gautų duomenų analizę, tiek grunte su mazutu, tiek su dyzelinu buvo nustatytas statistiškai reikšmingas (p<0,05) skirtumas tarp liekamujų naftos produktų koncentracijų tiek kontroliniuose bandiniuose, tiek bandiniuose, kuriuose buvo įterpti cheminiai priedai. Mazutu užterštame grunte nustatyta, kad kaip oksidatorių panaudojus KMnO4 likutinė mazuto koncentracijos reikšmė buvo tris kartus statistiškai reikšmingai mažesnė nei kontroliniuose bandiniuose, tačiau nėra statistiškai reikšmingo skirtumo, kurį oksidatorių (ar kalio permanganatą ar vandenilio peroksidą) naudoti. Kai gruntas užterštas dyzelinu, tarp KMnO4 ir H2O2 naudojimo yra statistiškai reikšmingas skirtumas. Tai rodo, kad kalio permanganatas turi didesnę įtaką dyzelino degradacijai negu vandenilio peroksidas. Bandiniuose su KMnO4 liekamoji dyzelino koncentracija buvo tris kartus statistiškai reikšmingai mažesnė negu bandiniuose su H2O2 ir penkis kartus mažesnė nei kontroliniuose bandiniuose. Tiek bendrą, tiek naftą oksiduojančių mikroorganizmų skaičių teigiamai paveikė cheminiai priedai. Tiek grunte su mazutu, tiek su dyzelinu buvo nustatytas statistiškai reikšmingas (p<0,05) skirtumas tarp mikroorganizmų kiekio kontroliniuose bandiniuose ir bandiniuose, į kuriuos buvo įterpti oksidatoriai. Tiek KMnO4, tiek MnSO4 naudojimas sudarė geresnes sąlygas biodegraduoti dyzelinui ir mazutui dirvožemyje. Viso eksperimento metu stebėtas teigiamas mikroorganizmų augimas, naudojant skirtingo valentingumo Mn (druskas). įvairūs cheminiai priedai galėtų būti naudojami biovalymo technologiniame procese, kai dirvožemis yra užterštas skirtingais naftos produktais. Резюме Большинство современных технологий по очистке грунта от нефтепродуктов развиваются в направлении создания новых, более эффективных биоaгентов, способствующих деструкции нефтепродуктов в грунте. Альтернативное направление развития данных технологий заключается в ускорении размножения микроорганизмов,присутствующих в грунте, и тем самым ускорении биодеградации нефтепродуктов. Исследование биодеградациидизельного топлива и мазута в грунте проводилось при использовании химических добавок (оксидаторов). Проводилось исследование влияния H2O2,KMnO4 и MnSO4 на изменение конечной концентрации дизельного топливаи мазута, а также на изменение общего количества нефтеусваивающих микроорганизмов. Статистический анализэкспериментальных данных показал, что в грунте с мазутом, так же, как и в грунте с дизельным топливом, существует статистически значимая разница (p < 0,05) между концентрациями нефтепродуктов в контрольных пробахи в пробах грунта с содержанием химических добавок. Установлено, что в грунте, загрязненном мазутом, во время использования оксидатора KMnO4значение конечной концентрации нефтепродукта было в 3 раза статистически менее значимое, чем в контрольных пробах, однако нет статистически значимой разницы, какой оксидаториспользовать – H2O2 или KMnO4. В случае загрязнения грунта дизельным топливом было установлено, что между KMnO4 и H2O2 существует статистически значимая разница, что позволяет утверждать, что KMnO4имеет большее влияние на процесс деградации нефтепродукта, чем H2O2. В пробах с KMnO4статистически значимая разница конечной концентрации дизельного топлива в грунте была в 3 раза меньше, чем с H2O2, и в 5 раз меньше, чем в контрольных пробах. Химические добавки положительно воздействовали и на общее количество микроорганизмов, ина количество нефтеусваивающих микроорганизмов. Использование KMnO4 и MnSO4 способствовало улучшениюусловий биодеградации дизельного топлива и мазута в грунте. Во время всего эксперимента, используя соли Mnразной валентности, наблюдался постоянный рост количества микроорганизмов. На основании результатов данного исследования можно рекомендовать различные анализированные добавки к использованию в технологическом процессе биологической очистки грунта от различных нефтепродуктов. Reikšminiai žodžiai: dirvožemio valymo technologijos, biodegradacija, mazutas, dyzelinas, cheminiai priedai, mikrobiologinis aktyvumas Ключевые слова: технологии по очистке грунта, биодеградация, дизельное топливо, мазут, химические добавки, размножение микроорганизмо

Terms and methods of goat's rue seed inoculation with bacteria (Rhizobium galegae) preparations

Major parameters of nitragine production and goat’s rue inoculation were estimated in the laboratory and field experiments during the period 1997-2002. The soil of the experimental site is classed as Dystri-Endohypogleyic Albeluvisol (JI4-n), with a pHKCl value of 5.4-5.8, humus content 1.81-1.87 %, available P2O5 and K2O 135-148 and 122-140 mg kg-1 soil, respectively. Our experimental evidence suggests that the quality of nitragine and seed inoculation is affected by the storage conditions and period of the preparation and bacteria-treated seed as well as by the combination of seed inoculation with protective materials. Regardless of the storage conditions (+4oC or +26oC), high efficacy of nitragine preparation can be maintained for no longer than two weeks. Longer storage of the preparation or Rhizobium biomass, intended for nitragine production, is risky. When storing bacteria-treated seed, the proper bacterial titre persists for a week, and while inoculating with 10 % sugar solution –for two weeks. The highest efficacy of nitragine was identified in the first and second year of use of goat’s rue when the seed was inoculated on the sowing day and up to 7 days before sowing. Treatment of inoculated seed with 10 % sugar solution did not contribute to the enhancement of the symbiosis efficiency. A medium strong correlation was identified between Rhizobium efficacy and number of plant nodules, and formation of complex nodules (r = 0.65 and h = 0.71**). All inoculation combinations were economically useful. During the two years of swards use net profit totalled up to 391.7 Lt ha-1

INTENSITY OF THE MINERALIZATION OF ORGANIC MATTER IN THE DYSTRI ALBELUVISOL

Anthropogenic activities have a negative impact on the whole ecosystem stability and long-term soil productivity. Tillage is the oldestform of human impact on the environment, which is a significant increase in the twentieth century and has gained a new undesirabletraits. One of the side effects caused by intensive farming technologies - this is the decline in soil organic matter . In one keyindicator of the quality of the soil can be considered a common microbial biomass accumulation in the plowed layer. That microorganismsare the main decomposers of organic material, but the physical polluted soil reduces the number of microorganisms, slowbiochemical processes and incurred crop production losses. The aim - based on the isolated microorganisms in the population and toassess the intensity of mineralization, which tillage technology have the least negative impact on the soil of West Lithuanian.KEY WORDS: tillage, mineralization, soil microorganisms, Albeluvisol

Terms and methods of goat's rue seed inoculation with bacteria (Rhizobium galegae) preparations

Major parameters of nitragine production and goat’s rue inoculation were estimated in the laboratory and field experiments during the period 1997-2002. The soil of the experimental site is classed as Dystri-Endohypogleyic Albeluvisol (JI4-n), with a pHKCl value of 5.4-5.8, humus content 1.81-1.87 %, available P2O5 and K2O 135-148 and 122-140 mg kg-1 soil, respectively. Our experimental evidence suggests that the quality of nitragine and seed inoculation is affected by the storage conditions and period of the preparation and bacteria-treated seed as well as by the combination of seed inoculation with protective materials. Regardless of the storage conditions (+4oC or +26oC), high efficacy of nitragine preparation can be maintained for no longer than two weeks. Longer storage of the preparation or Rhizobium biomass, intended for nitragine production, is risky. When storing bacteria-treated seed, the proper bacterial titre persists for a week, and while inoculating with 10 % sugar solution –for two weeks. The highest efficacy of nitragine was identified in the first and second year of use of goat’s rue when the seed was inoculated on the sowing day and up to 7 days before sowing. Treatment of inoculated seed with 10 % sugar solution did not contribute to the enhancement of the symbiosis efficiency. A medium strong correlation was identified between Rhizobium efficacy and number of plant nodules, and formation of complex nodules (r = 0.65 and h = 0.71**). All inoculation combinations were economically useful. During the two years of swards use net profit totalled up to 391.7 Lt ha-1

Changes in the soil properties as affected by conventional and minimal soil tillage systems

A stationary field trial was set up at the Vėžaičiai Branch of the Lithuanian Institute of Agriculture in 2003. The soil of the experimental site is Dystrict Albeluvisol (texture sandy light loam). The objective of the study was to estimate the effects of primary soil tillage methods on the changes in the soil structure; chemical, and biological soil properties. The field trial involved two factors: factor A – deep ploughing; shallow ploughing; shallow tillage in the autumn. Factor B – different organic fertilisers – green manure of perennial grasses, straw and manure incorporation in the crop rotation: winter wheat-spring rape – spring barley, and red clover. The herbage of the first cut and aftermath for green manure and farmyard manure were incorporated in the respective plots. The experimental findings of the first crop rotation during the period 2004–2007 are summarised in this paper. Each year, after crop harvesting the soil was limed by 400 kg ha-1 CaCO3. At the end of a four-year crop rotation in the deep and shallow ploughed soil the pH level increased by 0.2 units, while in the sallow tillage soil the pH value did not change compared with the initial level before the trial establishment. A reduction in organic carbon and nutrient content in the shallow tillage topsoil 10–20 cm layer was established. Deep and shallow ploughed soil was rich in phosphorus, potassium and nitrogen. The highest amount of nutrients was determined in the deep and shallow ploughed topsoil (0–10 cm) layer. After cultivation the structure of moraine loam soil deteriorated. A reduction in the content of water stable aggregates (>0.25 mm) by 4–7 per cent units in the tilled soil was identified compared with the ploughless tillage soil

Pagrindinio žemės dirbimo įtaka dirvožemio sėklų bankui ir piktžolėtumui javų bei žolių sėjomainoje

In the shallow ploughing and shallow ploughless tillage treatments there were found 25.5% and 41.5% more weed seed species in the soil, compared with the conventional tillage treatment. The seeds of Chenopodium album L., Persicaria lapathifolia L., Fallopia convolvulus L. and Viola arvensis Murray were found in all tillage treatments. The distribution of F. convolvulus L., P. lapathifolia L. seeds was significantly influenced by soil tillage only, that of V. arvensis Murray by soil tillage and its interaction with soil fertility improvement measures, and that of Ch. album L. by soil fertility improvement measures only

Naftos produktų biodegradacinis aktyvumas dirvožemyje

The current study is aimed to determine how sewage sludge may impact the biodegradation activity of soil contaminated with oil products and what groups of microorganisms are most active in it. Bathihypogleyi-Dystric Albeluvisol (ABd-gld-w) with a texture of sandy loam was selected for laboratory tests. The soil was contaminated with heavy fuel oil 15 and 30 g kg-1, supplemented with sewage sludge to create three backgrounds: 1) without sludge, 2) 5% (50 g kg-1) and 3) 10% (100 g kg-1) of sludge for air-dried soil. The trend was determined that when treating soil contaminated with heavy fuel oil the highest treatment efficiency was achieved by supplementing the soil with 10% of activated sewage sludge. Microorganisms which take part in the process of biodegradation of heavy fuel oil demonstrated different levels of activity during the investigation period. Hydrocarbon-oxidizing bacteria and micromycetes are the most important groups of microorganisms involved in the degradation of heavy fuel oil products in the soil. The initial concentration of heavy fuel oil in the soil had no statistically significant differences for all analyzed groups of microorganisms, although the number of bacteria and micromycetes, capable of oxidizing oil products, was statistically significantly influenced by the degradation time. The increasing concentration of sewage sludge statistically significantly affected the total number of bacteria and actinobacteria

Sėjamoji judra (Camelina sativa L.) – alternatyvus išteklius biodyzelino gamybai

The current study hypothesizes that false flax (Camelina sativa L.), as a high-value biofuel feedstock, could be grown under humid conditions of western Lithuania and that nitrogen fertilisation could influence its seed yield and oil content. The following objectives were pursued: 1) to determine the optimum nitrogen fertiliser rate for winter (N0, N50, N100, N150) and summer (N0, N30, N60, N90, N120) types of false flax, 2) to estimate false flax seed oil content, its composition and feasibility to use it for the production of biodiesel fuel. The experiments were conducted in 2008–2011 at the Vėžaičiai Branch of the Lithuanian Research Centre for Agriculture and Forestry. It was revealed that the highest (1.28 t ha-1, in 2010) and (1.29 t ha-1, in 2011) as well as cost-efficient summer false flax seed yield was produced having fertilised with 90 kg ha-1 of nitrogen. Significantly highest (1.2 t ha-1, in 2011 and 1.6 t ha-1, in 2010) winter false flax seed yield was obtained having fertilised with N100. In our study, the seed oil content of summer false flax amounted to 40.3% and that of winter false flax was lower – 37.0%. Nitrogen fertilisation (N150 and N120) increased protein content in winter false flax seed from 22.98% to 26.97% and in summer false flax seed from 20.53% to 23.23% and did not reduce seed oil content. Methyl esters of false flax oil have a high iodine value and an especially high content of polyunsaturated linolenic acid: it reached 38.2% in winter false flax oil and 34.3% in summer false flax oil. [...

Naftos produktų biodegradacinis aktyvumas dirvožemyje

The current study is aimed to determine how sewage sludge may impact the biodegradation activity of soil contaminated with oil products and what groups of microorganisms are most active in it. Bathihypogleyi-Dystric Albeluvisol (ABd-gld-w) with a texture of sandy loam was selected for laboratory tests. The soil was contaminated with heavy fuel oil 15 and 30 g kg-1, supplemented with sewage sludge to create three backgrounds: 1) without sludge, 2) 5% (50 g kg-1) and 3) 10% (100 g kg-1) of sludge for air-dried soil. The trend was determined that when treating soil contaminated with heavy fuel oil the highest treatment efficiency was achieved by supplementing the soil with 10% of activated sewage sludge. Microorganisms which take part in the process of biodegradation of heavy fuel oil demonstrated different levels of activity during the investigation period. Hydrocarbon-oxidizing bacteria and micromycetes are the most important groups of microorganisms involved in the degradation of heavy fuel oil products in the soil. The initial concentration of heavy fuel oil in the soil had no statistically significant differences for all analyzed groups of microorganisms, although the number of bacteria and micromycetes, capable of oxidizing oil products, was statistically significantly influenced by the degradation time. The increasing concentration of sewage sludge statistically significantly affected the total number of bacteria and actinobacteria