• Authors:
    • Lajeunesse, J.
    • Pageau, D.
    • Fregeau-Reid, J.
    • Collin, J.
    • Vanasse, A.
    • Lanoie, N.
    • Durand, J.
  • Source: Canadian Journal of Plant Science
  • Volume: 90
  • Issue: 3
  • Year: 2010
  • Summary: Naked oat ( Avena sativa L.) harvested in the province of Quebec, Canada, develops on average 10% covered grains and sometimes more. The objective of this study was to determine the effect of soil type, herbicides and their application stages on the proportion of covered grains in naked oat genotypes. Three genotypes were evaluated over 2 yr at two experimental sites. At each site, trials were seeded on two different soil types and each entry was treated with one of three types of herbicides: bromoxynil/MCPA, dicamba/MCPA and thifensulfuron methyl/tribenuron methyl, and compared with a weed-free check. The herbicides were applied at Zadoks 12-13 and 22-23. Results showed that dicamba/MCPA herbicide, applied at Zadoks 12-13, increased covered grains compared with the weed-free check and more covered grains were produced with the application made at Zadoks 22-23. However, differences in genotype reactions were observed. Few differences were found among the other weed control treatments. The application of dicamba/MCPA at Zadoks 22-23 decreased yield and test weight, but increased kernel weight. The other weed control treatments had no effect on agronomic characteristics.
  • Authors:
    • WCI
  • Volume: 2010
  • Year: 2010
  • Summary: Welcome to the Western Climate Initiative (WCI). The WCI is a collaboration of independent jurisdictions working together to identify, evaluate, and implement emissions trading policies to tackle climate change at a regional level. This is a comprehensive effort to reduce greenhouse gas pollution, spur investment in clean-energy technologies that create green jobs and reduce dependence on imported oil.
  • Authors:
    • Ristolainen, A.
    • Sarikka, I.
    • Hurme, T.
    • Alakukku, L.
  • Source: Agricultural and Food Science
  • Volume: 19
  • Issue: 4
  • Year: 2010
  • Summary: Surface water ponding and crop hampering due to soil wetness was monitored in order to evaluate the effects of conservation tillage practices and perennial grass cover on soil infiltrability for five years in situ in gently sloping clayey fields. Thirteen experimental areas, each having three experimental fields, were established in southern Finland. The fields belonged to: autumn mouldboard ploughing (AP), conservation tillage (CT) and perennial grass in the crop rotation (PG). In the third year, direct drilled (DD) fields were established in five areas. Excluding PG, mainly spring cereals were grown in the fields. Location and surface area of ponded water (in the spring and autumn) as well as hampered crop growth (during June-July) were determined in each field by using GPS devices and GIS programs. Surface water ponding or crop hampering occurred when the amount of rainfall was clearly greater than the long-term average. The mean of the relative area of the ponded surface water, indicating the risk of surface runoff, and hampered crop growth was larger in the CT fields than in the AP fields. The differences between means were, however, not statistically significant. Complementary soil physical measurements are required to investigate the reasons for the repeated surface water ponding.
  • Authors:
    • Liski, J.
    • Kitunen, V.
    • Spetz, P.
    • Tuomi, M.
    • Sonninen, E.
    • Oinonen, M.
    • Jungner, H.
    • Vanhala, P.
    • Hämäläinen, K.
    • Fritze, H.
    • Karhu, K.
  • Source: Ecology
  • Volume: 91
  • Issue: 2
  • Year: 2010
  • Summary: Feedback to climate warming from the carbon balance of terrestrial ecosystems depends critically on the temperature sensitivity of soil organic carbon (SOC) decomposition. Still, the temperature sensitivity is not known for the majority of the SOC, which is tens or hundreds of years old. This old fraction is paradoxically concluded to be more, less, or equally sensitive compared to the younger fraction. Here, we present results that explain these inconsistencies. We show that the temperature sensitivity of decomposition increases remarkably from the youngest annually cycling fraction (Q10 , 2) to a decadally cycling one (Q10 ¼ 4.2–6.9) but decreases again to a centennially cycling fraction (Q10 ¼ 2.4–2.8) in boreal forest soil. Compared to the method used for current global estimates (temperature sensitivity of all SOC equal to that of the total heterotrophic soil respiration), the soils studied will lose 30–45% more carbon in response to climate warming during the next few decades, if there is no change in carbon input. Carbon input, derivative of plant productivity, would have to increase by 100–120%, as compared to the earlier estimated 70–80%, in order to compensate for the accelerated decomposition.
  • Authors:
    • Dilling, L.
    • Failey, E. L.
  • Source: Environmental Research Letters
  • Volume: 5
  • Issue: 2
  • Year: 2010
  • Summary: Land use and its role in reducing greenhouse gases is a key element of policy negotiations to address climate change. Calculations of the potential for enhanced terrestrial sequestration have largely focused on the technical characteristics of carbon stocks, such as vegetation type and management regime, and to some degree, on economic incentives. However, the actual potential for carbon sequestration critically depends on who owns the land and additional land management decision drivers. US land ownership patterns are complex, and consequently land use decision making is driven by a variety of economic, social and policy incentives. These patterns and incentives make up the 'carbon stewardship landscape'-that is, the decision making context for carbon sequestration. We examine the carbon stewardship landscape in the US state of Colorado across several public and private ownership categories. Achieving the full potential for land use management to help mitigate carbon emissions requires not only technical feasibility and financial incentives, but also effective implementing mechanisms within a suite of often conflicting and hard to quantify factors such as multiple-use mandates, historical precedents, and non-monetary decision drivers.
  • Authors:
    • Marinov-Serafimov, P.
  • Source: Selskostopanska Nauka (Agricultural Science)
  • Volume: 43
  • Issue: 2
  • Year: 2010
  • Summary: The study was conducted during 2005-2007 at the experimental field of Experimental stations in soybeans - Pavlikeni without irrigated conditions in secondary leaching on black earth in order to establish the possibility of an alternative control against weeds in soybean ( Glycine max [L.] Merr.) using allelopathic-mulching crop-oats. Relations between the two plant species, soybean-barley were followed in two factors: Factor A - the quantity of oats in the rate of propagation rate: a 1 - (Control manual removal of weeds, soybean monoculture) a 2 - (Control without manual removal of weeds, soybean monoculture) a 3 - 12%; a 4 - 25% and a 5 - 50%. Factor B - duration of the development of soybeans to emergence (VE): b 1 - flowering (R 2), b 2 - pod formation (R 4) and b 3 - technical ripeness (R 8). It was found that the use of oats as allelopathic-mulching culture in soy reduces the rate of sowing weed infestans from 33.0 to 66.0% and the cumulative amount of fresh and dry biomass (from 12.0 to 68.0%) of the group of late spring weeds, a disproportionate amount of the increased propagation norm; Weed suppression resolution allelopathic-mulching culture agrophytocenosa study is the result of limiting the density of some dicotyledonous annual weeds Amaranthus ssp., Abutilon theophrasti Medik. and Chenopodium album (L.), despite being down compensation processes in population density of Convolvulus arvensis L. uniformity in distribution of (J) - from -4.2 to -10.2; species composition (S) of weed communities is from 4 to 8 species, but in terms of their diversity (H) - from -5.9 to -21.2; complex effect of weed infestants and extent of the propagation rules of oats have a negative impact on yield of soybeans - kg/ha from 25.3 to 63.0 percent, the height of soybean flour (RCI varies from 0.11 to 0.35) and formed on fresh and dry biomass (RCI is in the range of 0.44 to 0.83) on the soybean, which can be offset by the reduced level of weed infestans in soybean agrophytotsenosis.
  • Authors:
    • Krogstad, T.
    • Bechmann, M.
    • Aronsson, H.
    • Ulen, B.
    • Øygarden, L.
    • Stenberg, M.
  • Source: Soil Use and Management
  • Volume: 26
  • Issue: 2
  • Year: 2010
  • Summary: In Scandinavia high losses of soil and particulate-bound phosphorus (PP) have been shown to occur from tine-cultivated and mouldboard-ploughed soils in clay soil areas, especially in relatively warm, wet winters. The omission in the autumn of primary tillage (not ploughing) and the maintenance of a continuous crop cover are generally used to control soil erosion. In Norway, ploughing and shallow cultivation of sloping fields in spring instead of ploughing in autumn have been shown to reduce particle transport by up to 89% on highly erodible soils. Particle erosion from clay soils can be reduced by 79% by direct drilling in spring compared with autumn ploughing. Field experiments in Scandinavia with ploughless tillage of clay loams and clay soils compared to conventional autumn ploughing usually show reductions in total P losses of 10-80% by both surface and subsurface runoff (lateral movements to drains). However, the effects of not ploughing during the autumn on losses of dissolved reactive P (DRP) are frequently negative, since the DRP losses without ploughing compared to conventional ploughing have increased up to fourfold in field experiments. In addition, a comprehensive Norwegian field experiment at a site with high erosion risk has shown that the proportion of DRP compared to total P was twice as high in runoff water after direct drilling compared to ploughing. Therefore, erosion control measures should be further evaluated for fields with an erosion risk since reduction in PP losses may be low and DRP losses still high. Ploughless tillage systems have potential side-effects, including an increased need for pesticides to control weeds [e.g. Elytrigia repens (L.) Desv. ex Nevski] and plant diseases (e.g. Fusarium spp.) harboured by crop residues on the soil surface. Overall, soil tillage systems should be appraised for their positive and negative environmental effects before they are widely used for all types of soil, management practice, climate and landscape.
  • Authors:
    • Il'in, A.
  • Source: Kormoproizvodstvo
  • Issue: 10
  • Year: 2009
  • Summary: Climate of the Republic of Yakutia is very severe and continental with winter temperatures below minus 40degreesC. Horses of the Yakutian breed are well adapted for cold winters and used to winter tebenevka, when they get forage from under snow. Usage of oat as winter forage for the Yakutian horse breed was studied in the Republic of Yakutia, Russia. Oat could be covered by snow during autumn frosts when plants are still green if sown at optimal time in Yakutia. Yield of green mass conserved under snow is 7.5 t/ha and horses can get 35-45% of this during single tebenevka and 70-75% when tebenevka is repeated. Dry matter of winter oat contains 11, 2 and 33% of protein, fat and cellulose, respectively. Detailed data are provided in 5 tables. Winter oat is recommended as forage for horses of Yakutian breed.
  • Authors:
    • Jauhiainen, L.
    • Peltonen-Sainio, P.
    • Kirkkari, A.
  • Source: Journal of Agricultural Science
  • Volume: 147
  • Issue: 1
  • Year: 2009
  • Summary: The oat kernel, caryopsis or groat, is generally covered with fine silky hairs termed trichomes. The trichomes of naked oat are partly lost during threshing and handling of grains when the lemma and palea are removed and the surface of the grain is exposed. Trichomes can cause itchiness and more serious reactions in those handling the grains. Trichomes also accumulate and form fine dust and can block up machinery. Trichomes are clearly problematic and growers of naked oat are eager to have oat cultivars with reduced numbers of trichomes. Experiments compared the differences in trichome numbers of naked-oat cultivars and threshing settings. The cultivars differed considerably in pubescence. Cultivars Lisbeth and NK 00117 had most trichomes and cv. Bullion the fewest. Completely bare or polished grains were not observed. Pubescence was not associated with grain weight or test weight. However, grains from the lowermost spikelets of the panicle had fewer trichomes than those from the uppermost spikelets. For cv. Bullion, some threshing settings, including increased cylinder speed, slightly increased grain polishing such that grains had some areas completely free of trichomes. Reduction of the concave clearance in the combine harvester had a similar effect. However, threshing settings did not affect the trichomes of cv. Lisbeth. Adjusting threshing machinery settings was generally not an efficient means of solving the problems associated with naked-oat trichomes, but cultivar differences existed and further efforts in breeding to reduce trichome numbers are required.
  • Authors:
    • Fortin, J.
    • Tremblay, G.
    • Ziadi, N.
    • Chantigny, M. H.
    • Rochette, P.
    • Angers, D. A.
    • Poirier, V.
  • Source: Soil Science Society of America Journal
  • Volume: 73
  • Issue: 1
  • Year: 2009
  • Summary: Both tillage and fertilizer management influence soil organic C (SOC) storage, but their interactive effects remain to be determined for various soil and climatic conditions. We evaluated the long-term effects of tillage (no-till, NT, and moldboard plowing, MP), and N and P fertilization on SOC stocks and concentrations in profiles of a clay loam soil (clayey, mixed, mesic Typic Humaquept). Corn (Zea mays L.) and soybean [Glycine max (L) Merr.] were grown in a yearly rotation for 14 yr. Our results showed that NT enhanced the SOC content in the soil surface layer, but MP resulted in greater SOC content near the bottom of the plow layer. When the entire soil profile (0-60 cm) was considered, both effects compensated each other, which resulted in statistically equivalent SOC stocks for both tillage practices. Nitrogen and P fertilization with MP increased the estimated crop C inputs to the soil but did not significantly influence SOC stocks in the whole soil profile. At the 0- to 20-cm depth, however, lower C stocks were measured in the plowed soil with the highest N fertilizer level than in any other treatment, which was probably caused by a greater decomposition of crop residues and soil organic matter. Conversely, the highest SOC stocks of the 0- to 20-cm soil layer were observed in the NT treatment with the highest N rates, reflecting a greater residue accumulation at the soil Surface. When accounting for the whole soil profile, the variations in surface SOC due to tillage and fertilizer interactions were masked by tillage-induced differences in the 20- to 30-cm soil layer.