• Authors:
    • Zegada-Lizarazu, W.
    • Walter, K.
    • Valentine, J.
    • Djomo, S. Njakou
    • Monti, A.
    • Mander, U.
    • Lanigan, G. J.
    • Jones, M. B.
    • Hyvonen, N.
    • Freibauer, A.
    • Flessa, H.
    • Drewer, J.
    • Carter, M. S.
    • Skiba, U.
    • Hastings, A.
    • Osborne, B.
    • Don, A.
    • Zenone, T.
  • Source: GCB Bioenergy
  • Volume: 4
  • Issue: 4
  • Year: 2012
  • Summary: Bioenergy from crops is expected to make a considerable contribution to climate change mitigation. However, bioenergy is not necessarily carbon neutral because emissions of CO2, N2O and CH4 during crop production may reduce or completely counterbalance CO2 savings of the substituted fossil fuels. These greenhouse gases (GHGs) need to be included into the carbon footprint calculation of different bioenergy crops under a range of soil conditions and management practices. This review compiles existing knowledge on agronomic and environmental constraints and GHG balances of the major European bioenergy crops, although it focuses on dedicated perennial crops such as Miscanthus and short rotation coppice species. Such second-generation crops account for only 3% of the current European bioenergy production, but field data suggest they emit 40% to >99% less N2O than conventional annual crops. This is a result of lower fertilizer requirements as well as a higher N-use efficiency, due to effective N-recycling. Perennial energy crops have the potential to sequester additional carbon in soil biomass if established on former cropland (0.44 Mg soil C ha(-1) yr(-1) for poplar and willow and 0.66 Mg soil C ha(-1) yr(-1) for Miscanthus). However, there was no positive or even negative effects on the C balance if energy crops are established on former grassland. Increased bioenergy production may also result in direct and indirect land-use changes with potential high C losses when native vegetation is converted to annual crops. Although dedicated perennial energy crops have a high potential to improve the GHG balance of bioenergy production, several agronomic and economic constraints still have to be overcome.
  • Authors:
    • Yang, C.
    • Wang, H.
    • Lemke, R. L.
    • Zentner, R. P.
    • Campbell, C. A.
    • Liang, C.
    • Gan, Y.
  • Source: European Journal of Agronomy
  • Volume: 43
  • Issue: November
  • Year: 2012
  • Summary: Growing interest in environmental quality has provided a strong incentive to examine how farming practices affect agricultural products' carbon footprints (CF), an environmental quality indicator. This study determined (i) the CF of spring wheat (Triticurn aestivum L.) grown in different cropping systems over 25 years, and (ii) the effect of soil organic carbon (SOC) changes over years on wheat CF. Wheat was grown in four cropping systems: (a) fallow-wheat (FW), (b) fallow-wheat-wheat (FWW), (c) fallow-wheat-wheat-wheat-wheat-wheat (FWWWWW), and (d) continuous wheat (ContW), in replicated field plots in Saskatchewan, Canada. Wheat CF was calculated at a system level with measured variables coupled with modeling approaches. Over the 25-year period, the soil under the ContW system gained organic C of 1340 kg CO2 eq ha(-1) annually, or 38%. 55%, and 127% more than those gained in the FWWWWW, FWW, and FW systems, respectively. The SOC gain more than offset the greenhouse gas (GHG) emissions occurred during wheat production, leading to negative emission values at -742 kg CO2 eq ha(-1) annually for ContW, and -459, -404, and -191 kg CO2 eq ha(-1) for FWWWWW, FWW, and FW systems, respectively. Wheat in the ContW system produced the highest grain yield and gained highest SOC over the years, leading to the smallest (more negative) CF value at -0.441 kg CO2 eq kg(-1) of grain, significantly lower than the CF values from the three other systems (-0.102 to -0.116 kg CO2 eq kg(-1) of grain). Without considering the SOC gain in the calculation, wheat CF averaged 0.343 kg CO2 eq kg(-1) of grain and which did not differ among cropping systems. Wheat is the largest agricultural commodity in Saskatchewan, and the way the crop is produced has significant impacts on environmental quality, reflected by its carbon footprint. Cropping systems with decreased fallow frequency was shown to significantly enhance soil carbon gains over the years, increase annualized crop yields, and effectively lower the carbon footprint of this important commodity. Crown Copyright (c) 2012 Published by Elsevier B.V. All rights reserved.
  • Authors:
    • Brandt, S. A.
    • Malhi, S. S.
    • Huang, G.
    • Liang, C.
    • Gan, Y.
    • Katepa-Mupondwa, F.
  • Source: The International Journal of Life Cycle Assessment
  • Volume: 17
  • Issue: 1
  • Year: 2012
  • Summary: Best agricultural practices can be adopted to increase crop productivity and lower carbon footprint of grain products. The aims of this study were to provide a quantitative estimate of the carbon footprint of selected oilseed crops grown on the semiarid northern Great Plains and to determine the effects of N fertilization and environments on the carbon footprint. Five oilseed crops, Brassica napus canola, Brassica rapa canola, Brassica juncea canola, B. juncea mustard, and Sinapis alba mustard, were grown under the N rates of 0, 25, 50, 100, 150, 200, and 250 kg N ha(-1) at eight environsites (location x year combinations) in Saskatchewan, Canada. Straw and root decomposition and various production inputs were used to calculate greenhouse gas emissions and carbon footprints. Emissions from the production, transportation, storage, and delivery of N fertilizer to farm gates accounted for 42% of the total greenhouse gas emissions, and the direct and indirect emission from the application of N fertilizer in oilseed production added another 31% to the total emission. Emissions from N fertilization were nine times the emission from the use of pesticides and 11 times that of farming operations. Straw and root decomposition emitted 120 kg CO(2)eq ha(-1), contributing 10% to the total emission. Carbon footprint increased slightly as N rates increased from 0 to 50 kg N ha(-1), but as N rates increased from 50 to 250 kg N ha(-1), carbon footprint increased substantially for all five oilseed crops evaluated. Oilseeds grown at the humid Melfort site emitted 1,355 kg CO(2)eq ha(-1), 30% greater than emissions at the drier sites of Scott and Swift Current. Oilseeds grown at Melfort had their carbon footprint of 0.52 kg CO(2)eq kg(-1) of oilseed, 45% greater than that at Scott (0.45 kg CO(2)eq kg(-1) of oilseed), and 25% greater than that at Swift Current (0.45 kg CO(2)eq kg(-1) of oilseed). Carbon footprint of oilseeds was a function of the rate of N fertilizer, and the intensity of the functionality varied between environments. Key to lower carbon footprint in oilseeds is to improve N management practices.
  • Authors:
    • Shabalina, E. V.
    • Korobitsyn, S. L.
    • Platunov, A. A.
  • Source: Kormoproizvodstvo
  • Issue: 1
  • Year: 2011
  • Summary: Productivity and fodder value of perennial legume and legume-grass mixtures under cover of vetch-oat mixture were studied in 2009-2010 in Kirov Region, Russia. Cover mixture consisted of spring vetch cv. Orlovskaya 4 and oat cv. Ulov with sowing rate of 0.12 and 0.06 t/ha, respectively. Red clover cv. Kirovskii 159, birds-foot trefoil cv. Solnyshko and cooksfoot cv. Khlynovskaya were used as undercrop mixture in following combinations: (1) red clover, (2) red clover + birds-foot trefoil, (3) birds-foot trefoil, (4) red clover + cooksfoot, (5) red clover + birds-foot trefoil + cooksfoot. Data on dry mass yield and number of fodder units per kg of dry mass for cover mixture and unvercover crops, as well as crude protein and cellulose content for unvercover crops are summarized in 2 tables. Productivity of cover mixture and unvercover crops varied from 3.81 to 4.18 t/ha, and from 3.86 and to 4.80 t/ha respectively with no significant difference between variants. The highest crude protein content of 17.2% was achieved in variant (3), but again with no significant difference between variants. Authors concluded that further work will be needed to achieve the high and balanced yield of cover and unvercover crops.
  • Authors:
    • Askegaard, M.
    • Olesen, J. E.
    • Kristensen, K.
    • Rasmussen, I. A.
  • Source: Agriculture, Ecosystems & Environment
  • Volume: 142
  • Issue: 3-4
  • Year: 2011
  • Summary: Two main challenges facing organic arable farming are the supply of nitrogen (N) to the crop and the control of perennial weeds. Nitrate leaching from different organic arable crop rotations was investigated over three consecutive four-year crop rotations in a field experiment at three locations in Denmark (12 years in total). The experimental treatments were: (i) crop rotation, (ii) catch crop and (iii) animal manure. Nitrate leaching was estimated from measured soil nitrate concentration in ceramic suction cells and modelled drainage. There were significant effects on annual N leaching of location (coarse sand > loamy sand > sandy loam) and catch crops (without > with). Including a grass-clover green manure on 25% of the area did not increase N leaching compared with crop rotations without green manure. Also the application of animal manure did not influence N leaching, probably because even in the manured treatments the application rate was lower than crop demand. The results identify management of crop and soil during autumn as the main determinant of N leaching. Nitrate leaching was lowest for a catch crop soil cover during autumn and winter (avg. 20 kg N ha -1), a soil cover of weeds/volunteers had on avg. 30 kg N ha -1, and the largest N leaching losses were found after stubble cultivation (avg. 55 kg N ha -1). The N leaching losses increased with increasing number of autumn soil cultivations.
  • Authors:
    • Stoddard, F. L.
    • Santanen, A.
    • Turakainena, M.
    • Tuulos, A.
    • Mäkelä, P. S. A.
  • Source: Acta Agriculturae Scandinavica, Section B - Soil & Plant Science
  • Volume: 61
  • Issue: 3
  • Year: 2011
  • Summary: Winter turnip rape (Brassica rapa spp. oleifera) is an underutilized crop that deserves to be revitalized for use in high-latitude agriculture. Many crop rotations around the world are dependent on the small-grain cereals, and turnip rape as a break crop, with its range of secondary chemicals, helps to suppress weeds, nematodes and pathogenic fungi. It may be used as an energy crop, it can restrict erosion and nutrient leaching while also improving soil structure and fertility, and it requires relatively low inputs. Although winter turnip rape was once the major oil crop in Finland, in the 1970s it was replaced by spring turnip rape, the lower erucic acid and glucosinolate contents of which made it suitable for food and feed uses. Winter hardiness of the crop could be improved, and industrial end uses, such as lubricants for which high erucic acid content is preferred, targeted in the first instance. Breeding progress would be accelerated by a change from the predominantly self-incompatible breeding system to self-compatibility, now available in modern germplasm, and this would allow use of other rapid breeding methods, such as doubled haploidy. Thus, the many advantages of the winter turnip rape crop would repay its return to agriculture. In this review we will introduce the many utilization possibilities of the crop as well as give background on why more attention and research efforts should be paid towards this crop. We will also indicate some of the array of factors that have a marked role in an attempt to ecologically intensify crop production.
  • Authors:
    • Jauhiainen, L.
    • Peltonen-Sainio, P.
    • Hakala, K.
  • Source: The Journal of Agricultural Science
  • Volume: 149
  • Year: 2011
  • Summary: Global warming has accelerated in recent decades and the years 1995-2006 were the warmest ever recorded. Also, in Finland, the last decade has been exceptionally warm. Hence, this study examines how current field crop cultivars, adapted to northern long-day conditions and short growing seasons, have responded to the elevated temperatures, especially with regard to determination of yield potential and quality. These comparisons were carried out with spring and winter wheat (Triticum aestivum L.), oats (Avena sativa L.), barley (Hordeum vulgare L.), winter rye (Secale cereale L.), pea (Pisum sativum L.) and rapeseed (turnip rape, Brassica rapa L. and oilseed rape, B. napus L.). Long-term data sets of MTT Official Variety Trials and the Finnish Meteorological Institute were used to study crop responses to precipitation and elevated temperatures at different growth phases. The MTT data sets were also grouped into experiments that could be considered typical of the temperature conditions in the period 1971-2000 seasons (termed '1985' conditions) or typical of the period 2010-39 (termed '2025'). At elevated temperatures, yields generally declined in these relatively cool growing conditions of northern Europe, except for pea. Elevated temperatures tended to have negative effects both in the pre- and post-anthesis phases, but the response depended on species. The response was probably associated with reduced water availability, which limited yield determination, especially in early growth phases. For example, in spring cereals a decrease in early summer precipitation by 10 mm decreased yields by 45-75 kg/ha. As warmer conditions also typically hastened development and growth in such generally cool growing conditions of Finland, it is essential that breeding programmes produce cultivars that are less sensitive to elevated temperatures, which are likely to become more frequent in future.
  • Authors:
    • Jauhiainen, L.
    • Peltonen-Sainio, P.
    • Sadras, V. O.
  • Source: Field Crops Research
  • Volume: 124
  • Issue: 2
  • Year: 2011
  • Summary: In the northernmost European environments of Finland, large variability in the yield and quality of crops is a critical source of uncertainty for growers and end-users of grain. The aims of this study were (i) to quantify and compare the plasticity, i.e., cultivar responsiveness to environment, in yield of spring oat, spring wheat, six-row barley, two-row barley, winter rye, winter wheat, turnip rape and oilseed rape, (ii) to explore the existence of hierarchies or positive correlations in the plasticity of agronomic, yield and quality traits and (iii) to probe for trends in yield plasticity associated with different eras of breeding for yield potential and agronomic traits. Plasticities of yield, agronomic and quality traits were derived as slopes of norms of reaction using MTT Agrifood Research Finland data sets combining long-term (1970-2008 for cereals and 1976-2008 for rapeseed) results from 15 to 26 locations. Plasticity of yield ranged typically between 0.8 and 1.2, was smallest for six-row barley (0.84-1.11) and largest for winter rye (0.72-1.36). We found two types of associations between plasticity of yield and yield under stressful or favourable conditions for cereals but none for rape. In spring wheat, oat and six-row barley, high yield plasticity was associated with crop responsiveness to favourable conditions rather than yield reductions under stressful conditions. Modern spring wheat cultivars had higher maximum grain yields compared to older ones at the same level of plasticity. In winter wheat and rye, high yield plasticity resulted from the combination of high yield in favourable conditions and low yield in stressful environments. Many associations between yield plasticity and other traits were identified in cereals: e.g., high yield plasticity was often associated with higher grain weight, more grains per square meter, later maturity (contrary to turnip rape), shorter plants, less lodging and lower grain protein content and in winter cereals with higher winter damage. (C) 2011 Elsevier B.V. All rights reserved.
  • Authors:
    • Jalli, M.
    • Huusela-Veistola, E.
    • Hannukkala, A. O.
    • Hakala, K.
    • Peltonen-Sainio, P.
  • Source: Agricultural and Food Science
  • Volume: 20
  • Issue: 1
  • Year: 2011
  • Summary: A longer growing season and higher accumulated effective temperature sum (ETS) will improve crop production potential in Finland. The production potential of new or at present underutilised crops (e. g. maize (Zea mays L.), oilseed rape (Brassica napus L.), lucerne (Medicago sativa L.)) will improve and it will be possible to grow more productive varieties of the currently grown crops (spring wheat (Triticum aestivum L.), barley (Hordeum vulgare L.), oats (Avena sativa L.)). Also cultivation of autumn sown crops could increase if winters become milder and shorter, promoting overwintering success. Climatic conditions may on the other hand become restrictive in many ways. For example, early season droughts could intensify because of higher temperatures and consequent higher evaporation rates. Current low winter temperatures and short growing season help restrict the development and spread of pests and pathogens, but this could change in the future. Longer growing seasons, warmer autumns and milder winters may initiate new problems with higher occurrences of weeds, pests and pathogens, including new types of viruses and virus vectors. Anoxia of overwintering crops caused by ice encasement, and physical damage caused by freezing and melting of water over the fields may also increase. In this study we identify the most likely changes in crop species and varieties in Finland and the pest and pathogen species that are most likely to create production problems as a result of climate change during this century.
  • Authors:
    • Li, G.
    • Luo, C.
    • Wang, X.
    • Niu, Y.
    • Gao, C.
    • Nan, Z.
    • Shen, Y.
    • Yang, J.
  • Source: Acta Prataculturae Sinica
  • Volume: 19
  • Issue: 1
  • Year: 2010
  • Summary: The effects of conventional tillage (t), conventional tillage with stubble retention (ts), no-tillage (nt), and no-tillage with stubble retention (nts) treatment on crop yield, soil total nitrogen and carbon, total organic carbon, oxidizible organic carbon, and carbon pool management index (CPMI) were investigated within a maize-wheat-soy rotation system in the western Loess Plateau. Total crop yield for ten harvests during the years 2001 to 2007 under ts and nts treatments increased by 3.63 and 1.62 g/kg compared with conventional tillage, but decreased by 2.48 g/kg on the nt treatment. Total nitrogen contents under nts treatment were 15.4%, 30.2% and 16.2% higher than t, ts and nt treatments. Total carbon under nts treatment was significantly increased by 2.04 g/kg and total organic carbon were 2.50, 1.56 and 1.70 g/kg higher than under t, ts and nt treatment, respectively. Easily oxidized organic carbon under nts was 2.13 g/kg higher than under t treatment. TN/TC decreased by 12.75%, 15.97%, 6.87% and 24.16% under t, ts, nt and nts treatments. The CPMI under ts, nt and nts were 12.6%, 20.1% and 46.6% higher than under t, both stubble retention and no-till were beneficial to increasing the soil organic carbon content and improving the quality of the carbon pool.