• Authors:
    • Maraseni, T. N.
    • Cockfield, G.
    • Maroulis, J.
  • Source: Journal of Environmental Science and Health, Part B: Pesticides, Food Contaminants, and Agricultural Wastes
  • Volume: 45
  • Issue: 6
  • Year: 2010
  • Authors:
    • Brown, S.
    • Pearson, T.
  • Year: 2010
  • Summary: From exec. summary: ...The purpose of the study was to develop a methodology that could be used to calculate emission reduction offsets from activities associated with nitrogen-based fertilizers in US agriculture. To have credibility in the developing carbon market the methodology would have to accurately represent the impact on the atmosphere and would involve the input of significant site-specific data. Thus the Intergovernmental Panel on Climate Change (IPCC)'s Tier 1 approach is far from sufficient as it simply multiplies the quantity applied by defaults to calculate emissions. Yet a methodology must not be excessively expensive to implement as it would preclude the possibility of any project being implemented thus direct measurement of nitrous oxide from fields using measurement chambers could not be considered. A methodology was chosen for testing that included site specific information on type of fertilizer, soil carbon concentration, drainage, pH, soil texture and crop type. The highly parameterized, tested and peer-reviewed model DNDC (Denitrification-Decomposition) was used to estimate the "real" atmospheric impact at the test sites. Test sites were chosen in Arkansas (cotton), Iowa (corn) and California (lettuce) for the 2009 growing season.... Neither the IPCC Tier 1 method nor the new method proposed here based on Bouwman et al (2002) are sufficient for an offset project methodology that would be able to evaluate atmospheric impact of a broad range on fertilizer management practices. Therefore alternative approaches must be considered.... This comparison highlighted a further weakness of the simplified models; the simplified models can only evaluate the impacts of changes in quantify of fertilizer applied not in the methods of application....The recommendation arising from this report is to develop an offset methodology based on the application of DNDC for projects. A DNDC methodology will require expertise but atmospheric integrity is better guaranteed, monitoring would likely be inexpensive and costs would be low considering that offset projects are likely to consist of aggregations of large numbers of farms.
  • Authors:
    • van Groenigen, K. J.
    • van Kessel, C.
    • Oenema, O.
    • Velthof, G. L.
    • van Groenigen, J. W.
  • Source: European Journal of Soil Science
  • Volume: 61
  • Issue: 6
  • Year: 2010
  • Summary: Agricultural soils are the main anthropogenic source of nitrous oxide (N2O), largely because of nitrogen (N) fertilizer use. Commonly, N2O emissions are expressed as a function of N application rate. This suggests that smaller fertilizer applications always lead to smaller N2O emissions. Here we argue that, because of global demand for agricultural products, agronomic conditions should be included when assessing N2O emissions. Expressing N2O emissions in relation to crop productivity (expressed as above-ground N uptake: "yield-scaled N2O emissions") can express the N2O efficiency of a cropping system. We show how conventional relationships between N application rate, N uptake and N2O emissions can result in minimal yield-scaled N2O emissions at intermediate fertilizer-N rates. Key findings of a meta-analysis on yield-scaled N2O emissions by non-leguminous annual crops (19 independent studies and 147 data points) revealed that yield-scaled N2O emissions were smallest (8.4 g N2O-N kg-1N uptake) at application rates of approximately 180-190 kg Nha-1 and increased sharply after that (26.8 g N2O-N kg-1 N uptake at 301 kg N ha-1). If the above-ground N surplus was equal to or smaller than zero, yield-scaled N2O emissions remained stable and relatively small. At an N surplus of 90 kg N ha-1 yield-scaled emissions increased threefold. Furthermore, a negative relation between N use efficiency and yield-scaled N2O emissions was found. Therefore, we argue that agricultural management practices to reduce N2O emissions should focus on optimizing fertilizer-N use efficiency under median rates of N input, rather than on minimizing N application rates.
  • Authors:
    • ERS
  • Volume: 2010
  • Year: 2010
  • Authors:
    • Ju, X. T.
    • Qiu, S. J.
  • Source: Better Crops with Plant Food
  • Volume: 94
  • Issue: 4
  • Year: 2010
  • Summary: In the north China plain, the amount of N fertilizer and irrigation application in greenhouse vegetable systems is about three to five times that in conventional cereal systems. Over a decade of shifting from the conventional cereal systems to greenhouse vegetables, the capacity for nutrient cycling within these greenhouse systems has fallen. Additionally, the content of inorganic C in the soil profile under greenhouse systems has shown a dramatic decline.
  • Authors:
    • Christie, P.
    • Streck, T.
    • Li, L.
    • Qin, Z. C.
    • Ingwersen, J.
    • Ju, X. T.
    • Qiu, S. J.
    • Zhang, F. S.
  • Source: Soil & Tillage Research
  • Volume: 107
  • Issue: 2
  • Year: 2010
  • Summary: In recent years large areas of conventional cereal production in China have been transferred to greenhouse production with huge excessive nitrogen (N) fertilizer application and massive irrigation. However, the effects of this change in land use on soil carbon and nitrogen pools remain to be explored. Here we report a comparative study in which paired soil samples were taken from four greenhouses and from adjacent conventional cereal fields. Soil organic carbon (SOC), carbonate carbon (IC), total nitrogen (TN) and mineral nitrogen (N min) to 100 cm depth and the soil active organic pools, including particulate organic matter (POM), soil microbial biomass (SMB) and dissolved organic matter (DOM), to 0-40 cm depth were determined. The natural isotopic signatures of SOC, TN and POM were also analyzed. In both production systems all of the carbon and nitrogen pools in the surface soil (0-10 cm) were greater than deeper in the soil profile except for dissolved organic nitrogen (DON) and NH 4-N. SOC and TN and dissolved organic carbon (DOC) concentrations were higher in the greenhouse system than in conventional cereal soils ( P>0.05). A similar trend was found for POM ( P0.05) and IC in the greenhouse system showed a dramatic decline. The SOC/TN ratios of different pools in the greenhouse soils were lower than in the conventional cereal system ( P>0.05). The SOC/TN ratio ranged from 8.4 to 10.0 in greenhouse soils and 8.5 to 11.7 in the cereal soils. At each depth POM content in the greenhouses (1.5-7.1 g kg -1) was significantly greater than that in the field soils (0.8-2.9 g kg -1) ( P
  • Authors:
    • Animesh, S.
  • Source: APANews
  • Issue: 37
  • Year: 2010
  • Summary: The cultivation of vegetables under Dendrocalamus asper plantation in Jharkhand, India, is briefly described. The five-year old plantation was intercropped with potatoes, tomatoes, ginger and pea. The yield of potatoes, ginger and tomatoes decreased when cultivated in a bamboo plantation as compared to the data from the monoculture plantation. The performances of pea and ginger were found satisfactory.
  • Authors:
    • Gamzatov, I.
    • Muslimov, M.
  • Source: Kormoproizvodstvo
  • Issue: 12
  • Year: 2010
  • Summary: Continuous green fodder conveyor production system allows quality fodder supply during the grazing season. Field trials were conducted in Dagestan, the North Caucasus, Russia, with Red Steppe cattle. Data are tabulated on sowing dates and period of use of fodder crops, i.e. natural pastures, winter rape, winter rye + winter vetch, pea-oat + vetch-oat, regrowth of perennial grasses after hay cutting, Sudan grass, maize and maize + Sudan grass, sorghum, regrowth of Sudan grass and sorghum, maize sown after winter cereals grown for green fodder, maize and sorghum grown for silage for additional feed rations, winter rye after pea + oat, squash, pumpkin, fodder watermelon and fodder beet, and regrowth of natural pastures and meadows. The importance of natural pastures and drought resistant plants, such as sorghum crops, for production of high yield of fodder in dry conditions of Dagestan is considered.
  • Authors:
    • Nevenimo, T.
    • Quartermain, A.
    • Kurika, L.
    • Moxon, J.
  • Source: Science in New Guinea Journal
  • Volume: 30
  • Year: 2010
  • Summary: Papua New Guinea has over 200 crop species that are being utilized, but information in terms of quantity and quality is extremely variable and sparse for most of these crops. The crop species of interest as crops for the future are determined by growing conditions in agro-ecological zones but about 11 indigenous and 25 exotic species of fruits, nuts and vegetables have been identified. Future research needs to include evaluation of these crops for biodiscovery or biofuels, identification of those that are high yielding and of high nutritive value for food, assessment of those meeting domestic or export demand, pest and disease tolerance or resistance and suitability for crop rotations or intercropping. Post-harvest factors are also seen as important in the development of underutilized crops. The priority species include the major staples (aroids and sweet potato), galip nut ( Canarium indicum), noni ( Morinda citrifolia), okari ( Terminalia kaernbacchii), sago ( Metroxylon sagu), aibika ( Abelmoschus manihot), aupa ( Amaranthus spp.), pitpit ( Sacchurum edule), pandanus ( Pandanus spp.) and kava ( Piper methysticum). Galip nut is highlighted as an excellent example of where progress has been made in development for commercialization. Many factors are important for success but public-private partnerships are possibly one of the major factors.
  • Authors:
    • Prakash, H.
    • Dabbas, M.
    • Singh, R.
    • Singh, D.
  • Source: International Journal of Agricultural Sciences
  • Volume: 6
  • Issue: 1
  • Year: 2010
  • Summary: The study was carried out during 1997-98 to 2003-04 under Diversified Agricultural Support Project-a-World Bank Funded Project of Uttar Pradesh. The objective of this study was to increase the income and improve the cash flow system of small-marginal farmers, residing in the vicinity of town and urban. The pilot area was selected at Kaimganj in Farrukhabad district, having sandy loam to loam soils and maximum area cover with plantation crops viz., mango, ber and guava. Five to seven year old mango fields were selected for two tier cropping system. The alleys of mango tree intercropped with important vegetable crops like potato, brinjal, pumpkin, vegetable pea, garlic and onion, because the local market is available for the disposal of these vegetable crops. Generally, farmers planted Dashari mango at the distance of 8*8 m in rows. The associated crop of potato planted at the distance of 50 cm apart on 12 ridges between two rows of mango and adjusted 75% plant stand. Onion planted in 40 rows at 15 cm apart in the interspaces of two rows of mango and 75% plant stand was adjusted. Three rows of pumpkin were planted between two rows of mango at 200*50*75 cm apart and adjusted 75% plant population. Vegetable pea planted in 20 rows at 30 cm apart between two rows of mango and plant stand was adjusted 75%. Brinjal planted at 60 cm apart in 10 rows between two rows of mango and adjusted 72% plant population in interspaces of mango. The 75% plant stand of garlic was adjusted with plantation of 40 rows at 15 cm apart between two rows of mango. Potato, brinjal, green fruits of pumpkin, green pods of vegetable pea, garlic and onion yield 225, 218, 278, 92, 73, and 255 q/ha, respectively. The mango based cropping systems have maintained cash flow system and improved the economic status of farming community. The standards of living of small and marginal farm families scaled up and created eco-friendly environment.