• Authors:
    • Hoffmann, M.
    • Donaghy, P.
    • Stunzer, A.
    • Bray, S.
    • Gowen, R.
    • Rolfe, J.
    • Stephens, M.
  • Source: Small-Scale Forestry
  • Volume: 9
  • Issue: 4
  • Year: 2010
  • Authors:
    • Radford, B. J.
    • Thornton, C. M.
    • Huth, N. I.
    • Thorburn, P. J.
  • Source: Agriculture, Ecosystems & Environment
  • Volume: 136
  • Issue: 3-4
  • Year: 2010
  • Authors:
    • Maraseni, T. N.
    • Cockfield, G.
    • Maroulis, J.
  • Source: The Journal of Agricultural Science
  • Volume: 148
  • Year: 2010
  • Authors:
    • Renouf, M. A.
    • Wegener, M. K.
    • Pagan, R. J.
  • Source: The International Journal of Life Cycle Assessment
  • Volume: 15
  • Issue: 9
  • Year: 2010
  • Authors:
    • Fernandez, P. L.
    • Álvarez, C. R.
    • Schindler, V.
    • Taboada, M. A.
  • Source: Geoderma
  • Volume: 159
  • Issue: 1-2
  • Year: 2010
  • Summary: The grazing of crop residues during the winter in integrated crop-livestock systems can either increase soil bulk density (BD) by compaction or decrease BD by swelling, as a function of gravimetric soil water content (GW) during grazing. A field experiment was conducted from 2005 to 2008 to evaluate the BD response to grazing in a no-till silty loam soil (Typic Argiudoll) of the Pampas region of Argentina. Soil BD (core method), GW data and the calculated air volume (AV) were obtained from the 0-50 mm and 50-100 mm layers at different sampling times from ungrazed and grazed treatments. Over most of the study period (2006 through 2008) soil BD showed little impact from grazing, with minimal temporal variation (1.32-1.46 Mg m -3). This stable behavior was ascribed to low rainfall and relatively low GW values at the time when soil was trampled by livestock and routinely trafficked by machinery. Soil BD in the upper (0-50 mm) layer was significantly (p330 g kg -1 in the ungrazed treatment and GW was >240 g kg -1 in the grazed treatments. Grazing accentuated the soil kneading process that promoted air entrapment. Our results suggest in this no-tilled silt loam soil that winter grazing of crop residues caused no deterioration of topsoil porosity in the no-tilled silty loam soil.
  • Authors:
    • Ghosh, P. K.
    • Das, A.
    • Saha, R.
    • Kharkrang, E.
    • Tripathi, A. K.
    • Munda, G. C.
    • Ngachan, S. V.
  • Source: Current Science
  • Volume: 99
  • Issue: 7
  • Year: 2010
  • Summary: Productivity of rainfed monocropping farming system in North Eastern Region of India is low and it is a high economic risk activity. Intensive natural resources mining, continuous degradation of natural resources (soil, water, vegetation) and practice of monocropping under conventional agricultural practices will not ensure farm productivity and food security in the coming years. In order to keep the production system in different land situations sustainable, conservation agriculture based on no-till system is an alternative to reconcile agriculture with its environment and overcome the imposed constraints of climate change and continuous inputs cost. Studies on conservation tillage and residue management in different land situations were conducted during 2006-2009 and they are highlighted in this article. In terrace upland, growing mustard completely on residual moisture following upland rice/maize was possible when it is practised under conservation tillage (crop residue of all crops, including weed biomass incorporated). Similarly, in valley upland, growing second crop of pea in rice fallow is possible if two-thirds or half of rice residues are retained on the soil surface under zero tillage. A long-term study (2006-2009) revealed that double no-till practice in rice-based system is cost-effective, restored soil organic carbon (70.75%), favoured biological activity (46.7%), conserved water and produced yield (49%) higher than conventional tillage. Therefore, conservation tillage practised in terrace upland, valley upland and low-land situations ensured double-cropping, improved farm income and livelihood in rainfed NE India.
  • 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:
    • Brown, S.
    • Grimland, S.
    • Pearson, T. R. H.
  • Year: 2010
  • Summary: From exec summary: "....The basis of the direct and indirect emission calculations is a detailed empirical model that is discussed in the companion report to this work (hereafter referred to as the modified Bouwman model-MBM). The MBM incorporates various factors including quantity of fertilizer used, type of fertilizer, soil texture and drainage, pH and soil carbon concentration to predict nitrous oxide emissions. The companion report shows that the approach of the MBM is not sufficient at the project level, however, for a broad national analysis the approach is ideal....Our analysis resulted in an estimate of total annual N2O emission of 61 million tons of carbon dioxide equivalent for the three crops across the 31 states. Seventy percent of these emissions were from corn fields, 25% from wheat fields and 5% from cotton.
  • Authors:
    • RGGI
  • Volume: 2010
  • Year: 2010
  • Summary: The Regional Greenhouse Gas Initiative (RGGI) is the first market-based regulatory program in the United States to reduce greenhouse gas emissions. RGGI is a cooperative effort among the states of Connecticut, Delaware, Maine, Maryland, Massachusetts, New Hampshire, New York, Rhode Island, and Vermont. Together, these states have capped and will reduce CO2 emissions from the power sector 10 percent by 2018.
  • Authors:
    • Waggoner, J. A.
    • Conover, D. M.
    • Kreuter, U. P.
    • Ansley, R. J.
    • Baker, S. A.
    • Dowhower, S. L.
    • Teague, W. R.
  • Source: Agriculture, Ecosystems & Environment
  • Volume: 137
  • Issue: 1
  • Year: 2010
  • Summary: This paper examines if post-fire deferment and periodic rests provided by rotational grazing allowed for more rapid recovery of soil cover, soil chemical and physical parameters, and vegetation composition after summer patch burning than continuous grazing. We evaluated the recovery of native rangeland vegetation and soils subjected to summer patch burns in continuously and rotationally grazed pastures in 2002, 2003 and 2004. Each year, 12% of each treatment replicate was burned as a single patch in a different, non-adjacent area under continuous grazing, and as a single paddock of a rotationally grazed 8-pasture-1-herd system. Recovery of vegetation and soils on burned patches were measured annually until the summer of 2006 and compared to those in immediately adjacent unburned areas in both grazing treatments. Herbaceous cover and biomass took 2 years to recover to control levels on soils with greater mesquite cover and more C-3 grasses, and 3 years on soils with more C-4 grasses. The rotational grazing treatment had less bare ground and lower soil temperatures on both unburned and burned areas than the continuously grazed treatment, which has significant implications for infiltration rates, runoff and erosion in favor of the rotational management. Soil C and C to N ratios were also higher with rotational grazing. Soil physical parameters were not affected by either the burn or grazing treatments but the presence of trees reduced soil temperature, improved soil physical parameters and infiltration rate relative to open grassland.