• Authors:
    • Satkus, A.
    • Velykis, A.
  • Source: Zemdirbyste-Agriculture
  • Volume: 97
  • Issue: 2
  • Year: 2010
  • Summary: Experiments were carried out during 2007-2009 at the Joniskelis Experimental Station of the Lithuanian Institute of Agriculture on a clay loam Endocalcari-Endohypogleyic Cambisol (CMg-n-w-can). The study was designed to assess the effects of shallow ploughing and ploughless tillage as well as its combinations with other agronomic practices incorporation of lime sludge, cover crops (mixture of white mustard and oilseed radish) for green manure and mulch, improving soil condition and environment protection on the spread of weeds in a field pea crop and field pea productivity. It was found that when the post-sowing period was dry, reduced tillage of clay loam soil resulted in a higher weed incidence as well as a reduction in field pea yield, especially when leaving a cover crop for mulch during winter without tillage in autumn, as compared to deep ploughing. Under such conditions and due to reduced tillage, the spread of Galium aparine L. and Chenopodium album L. was wider, and in the cases of low field pea crop density as well as poor competition abilities, the mass of weeds increased. When the moisture was sufficient for field pea to emerge during post-sowing period, the spread of annual weeds was lower due to reduced tillage. Incorporation of lime sludge together with ploughless tillage helped to prevent the spread of weeds and reduction of field pea yield and was more favourable compared to ploughing.
  • Authors:
    • Țărau, D.
    • Borza, I.
    • Dicu, D.
  • Source: Research Journal of Agricultural Science
  • Volume: 42
  • Issue: 3
  • Year: 2010
  • Summary: Studies were conducted on a cambic cernosiom, with a medium content of clay, dominant in the Prodagro West Arad agro-centre and representative for a large surface in the Banat-Crisana Plain, on the Arad cadasiral territory, Romania. The experimental factors considered include: soil work system; foliar phyto-sanitary treatment; classical system; and no-till system. From the geomorphological point of view, the perimeter on which the experiments are located belongs to the large physical-geographic unity called the Vinga High Plain. Relief present itself as a succession of high plain, almost even, with altitudes between 95-200 m, separated by wide valleys, rather deep, collected quite in exclusivity by Berecsau river (and less by Mires river). The zone between the rivers are well individuated in 5 steps layed in fan shape: Seceani (180 m), Alios (160 m), Vinga (150 m), Calacea (130 m), Satchinez (100 m) realized by Mires river at different geological moments an partly tectonically influenced. Hydrographically, the perimeter where the experiment is placed belongs to the hydrographic basin of Mires river which flows at approximately 2-3 km north from this. The pedophreatic levels are at 5.1-10 m depth (they do not interfere in the pedogenesis processes) in flat areas and between 1.5-3.0 m depth in the valleys. For wheat, the production was between 3613-4817 kg/ha, the highest production of 4817 kg/ha, being registered in the no-till system, treated and the lowest of 3613 kg/ha in the no-till system . For maize the obtained production had values of 3658-5680 kg/ha, the highest production of 5680 kg/ha, being registered in classic system treated and the lowest of 3658 kg/ha in no-till system untreated.
  • Authors:
    • Vuscan, A.
    • Brejea, R.
    • Bara, L.
    • Bara, C.
    • Samuel, A.
    • Borza, I.
    • Sandor, M.
    • Domuta, C.
    • Domuta, C.
  • Source: Research Journal of Agricultural Science
  • Volume: 42
  • Issue: 1
  • Year: 2010
  • Summary: This paper based on the research carried out during 2006-2008 in Agricultural Research and Development Station Oradea on a preluvosoil. All the soil profile are low acid (6.11-6.8), humus content (1.44-1.75%) is small and total nitrogen is low median (0.127-0.157). After 30 years of good soil management, good practices the soil phosphorus content became very good (from 22.0 ppm to 150.8 ppm) on ploughing depth, potassium content (124.5 ppm) is median. The source of irrigation water was a drill of 15 m depth. Irrigation water quality was very good: pH=7.2; Na +=12.9; mineral residue=0.5 g/l; CSR=-1.7; SAR=0.52. Ten to ten days determination of the soil moisture on 0-75 cm depth emphasized the presence of the pedological drought every year: 39 days in 2006; 104 days in 2007 and 81 days in 2008; soil moisture decreased below wilting point every year too: 5 days in 2006 and 2008 and 6 days in 2007. Irrigation use - 1100 m 3/ha in 2006, 2900 m 3/ha in 2007, 3350 m 3/ha in 2008 - for maintaining the soil water reserve between easily available water content and field capacity determined the improve of the soybean microclimate. The values of de Mrtonne aridity index (IdM) for optimum irrigated soybean characterized the microclimate like "wet" in 2006 (IdM=45.2) and 2007 (IdM=44.2) and like "wet I" in 2008 (IdM=53.4). Irrigation suspending in the different months of the soybean irrigation season determined a smaller values of IdM and a worse microclimate, too. The biggest soybean yield were obtained in the irrigated variant without irrigation suspending in the soybean irrigation season: 3510 kg/ha in 2006, 3170 kg/ha in 2007 and 4050 kg/ha in 2008. In comparison with this variant the yield losses from unirrigated variant were of 25.4% in 2006; of 81.7% in 2007 and of 66.6.% in 2008; the yield losses are very significant statistically. Very significant statistically are the yield losses from the variants with irrigation suspending in the months of soybean irrigation season, too. The inverse link between pedological drought and yield and the direct link between de Martonne and yield sustain, too the need of the irrigation for pedological drought control and for microclimate improve in soybean from Crisurilor Plain.
  • Authors:
    • Sabău, N. C.
    • Samuel, A.
    • Brejea, R.
    • Domuța, C.
    • Borza, I.
    • Bara, C.
    • Bara, L.
    • Vușcan, A.
    • Ciobanu, G.
    • Gîtea, M.
    • Moza, A.
    • Jurca, A.
    • Șandor, M.
    • Domuța, C.
  • Source: Research Journal of Agricultural Science
  • Volume: 42
  • Issue: 1
  • Year: 2010
  • Summary: The paper is based on the research carried out during 2007-2009 in the long term trial placed in 1990 on the preluvosoil from Agricultural Research and Development Station Oradea. The preluvosoil from the research field is characterized by the presence of the horizons Bt 1 (34-54 cm depth) and Bt 2 (54-78 cm depth); the colloid clay eluviation determined to appear the El horizon with 31.6% colloid clay. On 0-20 cm depth, the soil has a big percentage of macroaggregates (Phi >0.25 mm), 47.5% bulk density is of 1.41 g/cm 3 and total porosity is median one, hydraulic conductivity is of 21.0 mm/h. The values of the pH indicates a low acid soil, humus, total nitrogen, phosphorus and potassium content are low. The source of irrigation water was a drill of 15 m depth. The chemical parameters of the irrigation water were the following: fixed mineral residue 0.5 g/l; SAR index 0.52; CSR index=-1.7%; N. Florea class=II; there are not some problems regarding the use of irrigation use. There are two factors of the experiment: crop rotation (wheat-monocrop, maize-wheat; maize-soybean-wheat) and water regime (unirrigated; irrigated). Optimum water provisionment was assured in the irrigated variant maintaining the soil water reserve between easily available water content on 0-50 cm depth. The biggest protein and gluten content were determined in the wheat grains from maize-soybean-wheat crop rotation both in unirrigated and irrigated variant and the smallest values were registered in the wheat monocrop. In the irrigated variant the smaller values protein, wet and dry gluten were registered but the differences are unsignificant. The research results emphasized the importance of the crop rotation to obtain an wheat yield with good panification index. The research results are part in the project: PN-II-ID-PCE-2008 2; 690/2009 "The study of influences of some technological elements upon the wheat yield quality in the conditions of the North-Western part of Romania".
  • Authors:
    • Hu, C. S.
    • Ren, T. S.
    • Du, Z. L.
  • Source: Soil Science Society of America Journal
  • Volume: 74
  • Issue: 1
  • Year: 2010
  • Summary: Little information is available about their influences of conservation tillage on the distribution and storage of soil organic C (SOC) and total N in soil profiles in the North China Plain. We investigated the changes in SOC and total N as related to the shift from conventional to conservation tillage using a long-term field experiment with a winter wheat ( Triticum aestivum L.)-corn ( Zea mays L.) double cropping system. The experiment included four tillage treatments for winter wheat: moldboard plow without corn residue return (MP-R), moldboard plow with corn residue return (MP+R), rotary tillage (RT), and no-till (NT). Compared with the MP-R treatment, returning crop residue to the soil (MP+R, RT, and NT) increased SOC and total N in the 0- to 30-cm soil layer, but no distinct changes in SOC and total N concentration were observed among the four treatments at soil depths >30 cm. Compared with the MP+R treatment, the RT and NT treatments increased SOC and total N concentration significantly in the 0- to 10-cm layer but decreased SOC and total N concentration in the 10- to 20-cm layers. As a consequence, soil profile SOC and total N storage did not vary among the MP+R, RT, and NT treatments. Thus under the experimental conditions, conservation tillage (RT and NT) increased SOC and total N contents in the upper soil layers, but did not increase SOC and total N storage over conventional tillage (MP+R) in the soil profile.
  • Authors:
    • Zhang, J. P.
    • Sun, J. S.
    • Liu, Z. G.
    • Qiu, X. Q.
    • Duan, A. W.
    • Gao, Y.
    • Wang, H. Z.
  • Source: Agricultural Water Management
  • Volume: 98
  • Issue: 1
  • Year: 2010
  • Summary: In a field experiment in the Yellow River Basin conducted in 2007 and 2008, it was found that, under full irrigation, the roots of maize not only penetrated deeper than those of soybean but also extended into soybean stands underneath the space between inner rows of soybean. The roots of soybean, however, were confined mainly to the zone near the plants. Horizontal growth of the roots of both the crops was confined mainly to the soil layer 16-22 cm below the surface, a layer that lay above an existing plough pan. Root length density (RLD) was much higher in the top layer (0-30 cm deep) and in the zone closer to the plants. The exponential model proved suitable to describe the RLD vertically and horizontally in both sole cropping and in intercropping.
  • Authors:
    • Melander, B.
    • Munkholm, L. J.
    • Hansen, E. M.
    • Olesen, J. E.
  • Source: Soil & Tillage Research
  • Volume: 109
  • Issue: 1
  • Year: 2010
  • Summary: Finding ways of reducing nitrate leaching in Northern Europe has become an extremely important task, especially under the projected climate changes that are expected to exacerbate the problem. To this end, two field experiments were established under temperate coastal climate conditions to evaluate the effect of tillage, straw retainment and cropping sequences, including cover crops, on nitrate leaching. The experiments were established in autumn 2002 on a loamy sand with 92 g clay kg(-1) and a sandy loam with 147 g clay kg(-1). The tillage treatments were stubble cultivation to 8-10 cm or 3-4 cm, direct drilling, or ploughing to 20 cm. The hypothesis was that (i) decreasing soil tillage intensity would decrease leaching compared to ploughing, (ii) leaving straw in the field would decrease leaching compared to removing straw, and (iii) a spring/winter crop rotation with catch crops would be more efficient in reducing nitrate leaching than a winter crop rotation. Overall, we were not able to confirm the three hypotheses. The effect of soil tillage on leaching might be blurred because the studied crop rotations had a high proportion of winter crops and because catch crops were grown whenever the alternative would have been bare soil in autumn and winter. The spring/winter crop rotation with catch crops was not found to be more efficient in reducing nitrate leaching than the winter crop rotation. In contrast, in a single year the winter crop rotation showed significantly lower leaching than the spring/winter crop rotations, probably due to the spring/winter crop rotation including peas, which may be considered a high-risk crop. Our study highlights that management practices that improve biomass production throughout the year are crucial in order to tighten the nitrogen cycle and thereby reduce nitrate leaching. (C) 2010 Elsevier B.V. All rights reserved.
  • Authors:
    • Tabil, L. G.
    • Adapa, P. K.
    • Schoenau, G. J.
  • Source: Applied Engineering in Agriculture
  • Volume: 26
  • Issue: 4
  • Year: 2010
  • Summary: Compaction of low bulk density agricultural biomass is a critical and desirable operation for sustainable and economic availability of feedstock for biofuel industry. A comprehensive study of the compression characteristics (density of pellet and total specific energy required for compression) of ground non-treated and steam-exploded barley, canola, oat, and wheat straw obtained from three hammer mill screen sizes of 6.4, 3.2 and 1.6 mm at 10% moisture content (wb) was conducted. Four preset pressures of 31.6, 63.2, 94.7, and 138.9 MPa were applied using an Instron testing machine to compress samples in a cylindrical die. Ground steam-exploded barley straw at screen sizes of either 3.2 or 1.6 mm produced high density compacts, while ground steam-exploded canola, oat, and wheat straw at screen sizes of 6.4, 3.2 or 1.6 mm produced high density compacts. Steam-exploded barley straw for 3.2 mm at 138.9 MPa produced compacts having 13% higher density and consumed 19% lower total specific energy compared to non-treated straw. Steam-exploded canola straw for 1.6 mm at 138.9 MPa produced compacts having 13% higher density and consumed 22% higher total specific energy compared to non-treated straw. Steam-exploded oat straw for 3.2 mm at 94.7 MPa produced compacts having 19% higher density and consumed 13% higher total specific energy compared to non-treated straw. Steam-exploded wheat straw for 6.4 mm at 138.9 MPa produced compacts having 17% higher density and consumed 17% higher total specific energy compared to non-treated straw. Three compression models, namely: Jones model, Cooper-Eaton model, and Kawakita-Ludde model were considered to determine the pressure-volume and pressure-density relationship of non-treated and steam-exploded straws. Kawakita-Ludde model provided the best fit to the experimental data having R 2 values of 0.99 for non-treated straw and 1.00 for steam-exploded biomass samples. The steam-exploded straw had higher porosity than non-treated straw. In addition, the steam-exploded straw was easier to compress since it had lower yield strength or failure stress values compared to non-treated straw.
  • Authors:
    • Friedl, A.
    • Amon, B.
    • Boesch, P.
    • Leonhartsberger, C.
    • Bauer, A.
    • Amon, T.
  • Source: Clean Technologies and Environmental Policy
  • Volume: 12
  • Issue: 2
  • Year: 2010
  • Summary: Currently an increasing demand for renewable energy can be observed. A part of this demand could be covered by the production of energy from agrarian biomass. Due to the limited availability of arable land, food and feed production are starting to compete for agrarian resources. A way out of this dilemma is to develop concepts that are based on otherwise unused agrarian biomass like straw and include new technologies for the fermentation of lignocellulosic biomass. In this paper, the energy potentials of two different cropping systems are compared. In the energy-based crop rotation system all crops were used either for biogas or ethanol production. In the biorefinery-based approach, the various crops were used in cascades for the production of food as well as feed. Experimental laboratory work and field trials were combined to calculate energy and biomass yields of the crops under investigation. The results demonstrate that steam explosion pretreatment of wheat straw led to a 30% increase in the specific methane yield. The calculated energy output of the biorefinery-based crop rotation system amounted to a total of 126 GJ ha(-1) year(-1). Extrapolating this energy output to the total arable land of the EU-27 member states, 13,608 PJ of energy could be produced. Therefore, biorefinery-based crop rotation systems could provide approximately three times more energy to the European population than energy-based crop rotation systems.
  • Authors:
    • Hansson, M.
    • Adler, A.
    • Bergkvist, G.
    • Weih, M.
  • Source: Weed Research
  • Volume: 50
  • Issue: 5
  • Year: 2010
  • Summary: P>Elytrigia repens (syn. Elymus repens) is a perennial grass weed that is controlled by herbicides or by tillage. Both methods are expensive and may have negative effects on the environment. Therefore, alternative methods of weed control, such as using competition from under-sown perennial forage crops, are of interest. Red fescue can be sown together with winter wheat as a non-flowering understorey crop that has its main growth during late summer and autumn. This study quantified the effect of red fescue and E. repens on wheat biomass and tested the hypothesis that under-sown red fescue reduces the amount of E. repens rhizomes and thus the need for herbicides or tillage. Two field experiments in which winter wheat, red fescue and E. repens were grown in all possible combinations were conducted between 2003 and 2005. Elytrigia repens reduced wheat biomass by 8%, while red fescue had no significant effect on wheat biomass. Red fescue reduced late autumn biomass of E. repens rhizomes by 40%. The results suggest that red fescue sown with winter wheat can reduce propagation of E. repens during summer and autumn, without a significant reduction in wheat biomass.