Browsing by Author "Paustian, Keith"

Now showing 1 - 7 of 7
  • Aggregation and soil organic matter accumulation in cultivated and native grassland soils
    Six, J.; Elliott, E. T.; Paustian, Keith; Doran, J. W. (Soil Science Society of America, 1998)
    This study compares the impacts of no-tillage, conventional tillage, and native grasslands on three particulate organic matter (POM) fractions.
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    Agricultural mitigation of greenhouse gases: Science and policy options
    Paustian, Keith; Babcock, Bruce; Hatfield, Jerry L.; Lal, Rattan; McCarl, Bruce A.; McLaughlin, Sandy; Mosier, A.rvin; Rice, Charles; Roberton, G.Philip; Rosenberg, Norman J.; Rosenzweig, Cynthia; Schlesinger, William H.; Zilberman, David (Washington, D.C.: Conference on Carbon Sequestration, 2001)
    The focus of a forthcoming Council on Agricultural Science and Technology (CAST) report is to summarize and synthesize the most recent research on the potential to mitigate GHG emissions through improvements in agricultural and land management practices. The report is designed to inform policy and decision makers in government and industry, agricultural producers, environmental and other nongovernmental organizations, and the general public. A major objective of the report has been to bring together biophysical and ecological information with economics and policy analysis, to provide a clearer picture of the potential role of agriculture in GHG mitigation strategies. In addition, a major aim has been to address all three major greenhouse gases and to consider the potential tradeoffs and/or synergisms between practices aimed at carbon sequestration and mitigation of N2O and CH4 emissions, in order to understand the net effect of all three gases (CO2, N2O and CH4), which can be expressed as an aggregate global warming potential (GWP) value. It is hoped that this synthesis will inform the debate on GHG mitigation in ongoing national and international efforts to deal with global climate change. This paper presents a brief synopsis of some of the findings of the CAST report.
  • Bacterial and fungal abundance and biomass in conventional and no-tillage agroecosystems along two climatic gradients
    Frey, S. D.; Elliott, E. T.; Paustian, Keith (Elsevier, 1999)
    This study explores the relationships between tillage method, climate, and microbial community composition, and their effects on soil organic matter (SOM) decomposition rates and nutrient turnover and availability in agricultural soils.
  • Carbon Sequestration in microaggregates of no-tillage soils with different clay mineralogy
    Denef, K.; Six, J.; Merckx, R.; Paustian, Keith (Soil Science Society of America, 2004)
    This study compares the soil organic carbon (SOC) sequestration of three different soil types under no-tillage and conventional tillage. In all three soil types, soils under no-tillage had greater total SOC and greater C in microaggregates. More than 90% of the difference in total SOC between no-tillage and conventional tillage was attributable to the difference in microaggregate-associated C, regardless of clay mineralogy differences.
  • Soil aggregation and soil organic carbon stabilization: Effects of management in semiarid Mediterranean agro-ecosystems
    Álvaro-Fuentes, J.; Cantero-Martínez, C.; López, M. V.; Paustian, Keith; Denef, K.; Stewart, C. E.; Arrúe, J. L. (Soil Science Society of America, 2009)
    This study compared the combined and individual effects of three tillage systems and two cropping systems in a semiarid Mediterranean agroecosystem. The tillage systems were no-till (NT), reduced tillage (RT), and conventional tillage (CT); sites were cropped with either continuous barley or a barley-fallow system. Under both cropping systems, NT treatments had over 30% greater soil organic carbon (SOC) storage in the surface five cm of soil. The continuous barley treatment had greater SOC stabilization than the barley-fallow treatment only under no-till management. NT soils also showed a greater proportion of water stable macroaggregates. The authors conclude that the combined systems of no-till and fallow-suppression have the potential to increase stable SOC in the soil surface as well as improve overall soil structure and aggregation in the semiarid Mediterranean.
  • Soil carbon sequestration and associated economic costs for farming systems of the Indo-Gangetic Plain: A meta-analysis
    Grace, P. R.; Antle, J.; Aggarwal, Pramod K.; Ogle, S.; Paustian, Keith; Basso, B. (Elsevier, 2012)
    Carbon sequestration presents a unique opportunity for nation-states to accumulate monetary credit while promoting soil conservation and ecological sustainability. In this meta-analysis, previously measured data on carbon sequestration rates and local data were used to estimate the potential for carbon sequestration of wheat-based production systems within economic and ecological constraints in the Indo-Gangetic Plains of India. Over twenty years, using no-till practices in wheat-rice, maize-wheat, and cotton-wheat production systems would increase carbon sequestration by 60.7 Mt. However, this estimated differed according to carbon prices offered due to the costs associated with switching to no-till practices. Carbon prices of 200 USD Mg C-1 allowed for the highest amount of sequestration: 79 percent of the potential sequestration amount. Regional success varied, and the authors assert that climate and market imperfections are likely to skew estimations.
  • Soil structure and soil organic matter: I. Distribution of aggregate size classes and aggregate associated carbon
    Six, J.; Paustian, Keith; Elliott, E. T.; Combrink, C. (Soil Science Society of America, 2000)
    This study compares aggregate size and carbon in three different soils, each with three tillage treatments (native vegetation (NV), no-tillage (NT), and conventional tillage (CT)).