• Authors:
    • Silvan, N.
    • Minkkinen, K.
    • Saarinen, M.
    • Pearson, M.
    • Laine, J.
  • Source: Forest Ecology and Management
  • Volume: 283
  • Year: 2012
  • Summary: Soil preparation to expedite stand establishment after clearcutting is an extensively applied measure in peatland forest regeneration sites particularly in Fennoscandinavia. Thus far, the impact of preparing peat soil on greenhouse gas fluxes is a chapter unwritten in GHG research on forestry-drained peatlands. Not only is such information vital in order to accurately estimate the GHG balance nationally, it may dictate the very methods used to regenerate forests on peat soils in the future. Over a 22-month period, we studied the impacts of mounding and scalping relative to the control on soil CO2 (heterotrophic peat soil respiration, SRp), CH4, and N2O fluxes along a moisture gradient in a nutrient-poor, clearcut forestry-drained peatland. First, we measured instantaneous gas fluxes (g m(-2) h(-1)) of the microsite types (unprepared, mound, pit, scalp) within a given treatment plot (control, mounding, scalping) in order to estimate their annual rates (g m(-2) a(-1)). Then, we estimated annual flux rates for each treatment comprehensively by considering the surface area-based distribution of microsite types in the corresponding treatment plot, and finally, the overall climatic impact of GHG emissions expressed in terms of CO2 equivalents (100-year GWP) 2-3 years after clearcutting and soil preparation. Compared to the control microsites, instantaneous CO2 emissions from scalps and pits were lower while those from mounds equivalent. However, increased CO2 emissions from the unprepared microsites within prepared plots were observed in respect to those of the control. Comprehensively, the annual CO2 emission rates differed little between treatments, ranging between 929 and 1078 g m(-2) a(-1). Hence, neither mounding nor scalping accelerated annual SRp relative to the control treatment. Annual fluxes of CH4 were dependent on the position of the water table. In our wet block, the mounding treatment led to the greatest annual CH4 emissions (3.62 g m(-2) a(-1)), followed by the control (2.14 g m(-2) a(-1)) and scalping (1.05 g m(-2) a(-1)); in the dry block, however, only the scalping treatment was a net, though minimal, source of CH4 (0.80 g m(-2) a(-1)) while the other two treatments effectively consumed CH4 (mounding -0.16 g m(-2) a(-1); control -0.05 g m(-2) a(-1)). Though annual N2O emission levels were low (0.05-0.08 g m(-2) a(-1)), both soil preparation treatments increased the flux of N2O from peat soil compared to the control. When considering the fluxes of all three greenhouse gases, the cumulative impact of soil preparation (mounding or scalping) on the global warming potential of the nutrient-poor, clearcut peatland forest was negligible in respect to the control.
  • Authors:
    • Leblanc, H. A.
    • Harmand, J.-M.
    • Fernandez, M. P.
    • Nygren, P.
  • Source: Nutrient Cycling in Agroecosystems
  • Volume: 94
  • Issue: 2-3
  • Year: 2012
  • Summary: We compiled quantitative estimates on symbiotic N-2 fixation by trees in agroforestry systems (AFS) in order to evaluate the critical environmental and management factors that affect the benefit from N-2 fixation to system N economy. The so-called "N-2-fixing tree" is a tripartite symbiotic system composed of the plant, N-2-fixing bacteria, and mycorrhizae-forming fungi. Almost 100 recognised rhizobial species associated with legumes do not form an evolutionary homologous clade and are functionally diverse. The global bacterial diversity is still unknown. Actinorrhizal symbioses in AFS remain almost unstudied. Dinitrogen fixation in AFS should be quantified using N isotopic methods or long-term system N balances. The general average +/- A standard deviation of tree dependency on N-2 fixation (%Ndfa) in 38 cases using N isotopic analyses was 59 +/- A 16.6 %. Under humid and sub-humid conditions, the percentage was higher in young (69 +/- A 10.7 %) and periodically pruned trees (63 +/- A 11.8 %) than in free-growing trees (54 +/- A 11.7 %). High variability was observed in drylands (range 10-84 %) indicating need for careful species and provenance selection in these areas. Annual N-2 fixation was the highest in improved fallow and protein bank systems, 300-650 kg [N] ha(-1). General average for 16 very variable AFS was 246 kg [N] ha(-1), which is enough for fulfilling crop N needs for sustained or increasing yield in low-input agriculture and reducing N-fertiliser use in large-scale agribusiness. Leaf litter and green mulch applications release N slowly to the soil and mostly benefit the crop through long-term soil improvement. Root and nodule turnover and N rhizodeposition from N-2-fixing trees are sources of easily available N for the crop yet they have been largely ignored in agroforestry research. There is also increasing evidence on direct N transfer from N-2-fixing trees to crops, e.g. via common mycelial networks of mycorrhizal fungi or absorption of tree root exudates by the crop. Research on the below-ground tree-crop-microbia interactions is needed for fully understanding and managing N-2 fixation in AFS.
  • 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:
    • Hallikainen, A.
    • Kostiainen, E.
    • Turtiainen, T.
  • Source: Journal of Environmental Radioactivity
  • Volume: 102
  • Issue: 5
  • Year: 2011
  • Summary: A survey was carried out on the activity concentrations of 210Pb and 210Po in cereal grains produced in Finland. The cereal species were wheat ( Triticum aestivum), rye ( Secale cereale), oats ( Avena sativa) and barley ( Hordeum vulgare), which account for 90% of the Finnish consumption of cereal products. The survey consisted of 18 flour and 13 unprocessed cereal samples and one hulled grain sample from 22 flour mills. According to the results, the mean 210Pb/ 210Po concentrations in wheat grains, wheat flour, rye flour, oat grains and barley grains were 0.29, 0.12, 0.29, 0.36 and 0.36 Bq kg -1, respectively. Combined with the consumption rates of the products, we assess that the mean effective doses from 210Pb and 210Po in cereal products for the adult male and female population are 22 and 17 Sv per year, respectively.
  • Authors:
    • Hyovela, M.
    • Hurme, T.
    • Niskanen, M.
    • Laine, A.
    • Kontturi, M.
    • Peltonen-Sainio, P.
  • Source: Acta Agriculturae Scandinavica Section B-Soil and Plant Science
  • Volume: 61
  • Issue: 7
  • Year: 2011
  • Summary: Locally produced crop protein is urgently needed in Europe. Pea is a good protein source and is well adapted to northern conditions. Pea can fix nitrogen that the following crop in rotation can benefit from. In cereal-dominated cropping systems pea is a break crop disrupting the life cycle of cereal diseases, leading to less fungicide application and thereby minimizing off farm inputs and benefiting the environment. Grain legumes provide animals with protein and energy, and the seeds of pulse crops are complementary to those of cereals. Field peas can be cultivated in most parts of Scandinavia and interest in peas has increased for inclusion in organic farming. Growing pea as a sole crop is a challenge since its stem is prone to lodging thereby resulting in harvesting difficulties, reduced yield and decreased profits. Intercropping of pea with oat could minimize the above listed problems but to our knowledge proportion of seeds mixture of the two crops and selection of pea cultivars without compromising the pea yield, especially protein production, at high latitudes conditions is limited. Therefore, our objective was to evaluate performance of sole cropped pea (Karita, Perttu, Hulda) and oat (seed proportions 7.5% and 15%) and their intercrop combinations and establish an appropriate seed mixture for a pea-oat intercropping systems that prevents lodging without markedly reducing pea yield. Field experiments were conducted at three locations (Jokioinen, Mietoinen, Ylistaro) of the Agrifood Research Finland in 2002-2004. Intercropping peas with oats prevented peas from lodging and made their harvest easier. Optimal numbers of oats in pea intercrops were difficult to determine, varying according to pea cultivar and local growth conditions. Excess oats in the seed mixture or conditions favouring oat growth prevented peas from lodging but pea yield was decreased.
  • Authors:
    • Mikkola, H.
    • Rajaniemi, M.
    • Ahokas, J.
  • Source: Agronomy Research
  • Volume: 9
  • Issue: Special Issue I
  • Year: 2011
  • Summary: The aim of this study was to analyze greenhouse gas (GHG) emissions from oats, barley, spring wheat and rye production in Finland. The GHG emissions were analyzed in a conventional production chain, direct drilling chain and reduced tillage chain. The greenhouse gases were analyzed per kilogram grain (kg CO 2-eq. kg -1) and hectare (kg CO 2-eq. ha -1). The main part of the GHG emissions of the grain production chain originated from fertilizer manufacturing and soil. Soil emissions were a result of using N-fertilizer which induced N 2O emission and liming which induced CO 2-emission. GHG emissions from soil were about half of all emissions of grain production. Therefore, the N-fertilizer application rate had a strong direct and indirect effect on the GHG emissions. Wheat (2,330 kg CO 2-eq. ha -1) and rye (2,270 kg CO 2-eq. ha -1) had higher GHG emissions per hectare than oats and barley. The main reason for this was the higher application rate of N-fertilizer. The emissions of oats and barley were 1,800 and 1,930 kg CO 2-eq. ha -1. The yield had a strong impact on the emissions per kilogram of grain. Oats (570 g CO 2-eq. kg -1), barley (570 g CO 2-eq. kg -1) and wheat (590 g CO 2-eq. kg -1) had lower greenhouse emissions than rye. A low grain yield together with high N-fertilizer application rate caused higher greenhouse gas emission for rye (870 g CO 2-eq. kg -1). Direct drilling and reduced tillage resulted in some lower GHG emissions than conventional tillage. However, differences between production chains were minor.
  • 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.