Browsing by Author "Lal, Rattan"

Now showing 1 - 9 of 9
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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.
  • Residue management, conservation tillage and soil restoration for mitigating greenhouse effect by CO2-enrichment
    Lal, Rattan (Elsevier, 1997)
    This paper discusses the potential contribution of crop residue management, conservation tillage, and soil restoration toward mitigating the greenhouse effect through carbon sequestration. The author provides estimates of the possible annual C sequestration rate for each of these land management practices.
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    Root Characteristics of Perennial Warm-Season Grasslands Managed for Grazing and Biomass Production
    Bonin, Catherine; Flores, Joao; Lal, Rattan; Tracy, Benjamin F. (MDPI, 2013-07-08)
    Minirhizotrons were used to study root growth characteristics in recently established fields dominated by perennial C4-grasses that were managed either for cattle grazing or biomass production for bioenergy in Virginia, USA. Measurements over a 13-month period showed that grazing resulted in smaller total root volumes and root diameters. Under biomass management, root volume was 40% higher (49 vs. 35 mm3) and diameters were 20% larger (0.29 vs. 0.24 mm) compared to grazing. While total root length did not differ between grazed and biomass treatments, root distribution was shallower under grazed areas, with 50% of total root length in the top 7 cm of soil, compared to 41% in ungrazed exclosures. These changes (i.e., longer roots and greater root volume in the top 10 cm of soil under grazing but the reverse at 17-28 cm soil depths) were likely caused by a shift in plant species composition as grazing reduced C4 grass biomass and allowed invasion of annual unsown species. The data suggest that management of perennial C4 grasslands for either grazing or biomass production can affect root growth in different ways and this, in turn, may have implications for the subsequent carbon sequestration potential of these grasslands.
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    Soil carbon sequestration for advancing food security and offsetting CO2 Emissions
    Lal, Rattan (Blacksburg, VA: Virginia Tech, Office of International Research, Education, and Development (OIRED), 2009)
    Agricultural soil C sinks, potentially significant depository of atmospheric CO2, are important to numerous ecosystems services including mitigation and adaptation to climate change, improvements in quantity and quality of renewable fresh water resources, enhancement of biodiversity, and increase in agronomic productivity. Technical soil C sequestration potential depends on C lost during the prior land use, soil management, and the attendant degradation in soil quality. The global maximum soil C sink capacity is 78±12 Gt C, with the technical potential of C sequestration rates of 0.6 to 1.2 Gt C/yr in cropland coils, 0.14-1.0 Gt C/yr in restoring salt-affected soils, 0.6-1.7 Gt C/yr through desertification control, 0.8-1.0 Gt C/yr through afforestation in tropical forest ecosystems, and 0.3-0.5 Gt C/yr in the savanna ecosystems. Thus, the global potential of C sequestration in the terrestrial biosphere is 2.5-5.3 Gt C/yr. The most cost effective technologies are: conservation tillage and residue management, and improved agronomy practices, nutrient management, and rice management. Rates of soil C sequestration can be enhanced by improving the eco-efficiency of inputs used in agroecosystems (e.g., fertilizers, irrigation). Improvement in soil quality, by increasing soil organic C pool by 1 Mg/ha/yr in the root zone, can increase food production in developing countries by 32 million Mg/yr of grains and 9 million Mg/yr of roots and tubers. Adoption of conversation tillage and other recommended management practices can be promoted among resource-poor farmers by payments for ecosystem services; however, the price of soil C must be determined by fair, just and transparent criteria.
  • Soil degradative effects of slope length and tillage method on alfisols in western Nigeria II. Soil chemical properties, plant nutrient loss and water quality
    Lal, Rattan (John Wiley & Sons, Ltd., 1997)
    This paper assesses the effects of slope length (10-60m) and tillage method (conventional versus no-till) on soil chemical properties and nutrient loss in runoff water, evaluating both aggregate seasonal effects and month-by-month variation.
  • Soil organic carbon and fertility interactions affected by a tillage chronosequence in a Brazilian Oxisol
    Sá, J. C. D. M.; Cerri, C. C.; Lal, Rattan; Dick, W. A.; de Cassia Piccolo, M.; Feigl, B. E. (Elsevier B.V., 2008)
    This article describes a study that analyzes the impact of a tillage chronosequence on concentrations of soil organic carbon and its interactions with soil fertility in a Brazilian Oxisol. As land is converted from natural ecosystems to cropland, the properties of the soil are significantly affected. Moreover, as crop cultivation is intensified to a large scale, the methods used can be detrimental to the nutrient levels in the soil. This study suggests that long-term no-tillage is a useful strategy for improving fertility of soils with variable charge.
  • Stratification ratio of soil organic matter pools as an indicator of carbon sequestration in a tillage chronosequence on a Brazilian Oxisol
    Sá, J. C. D. M.; Lal, Rattan (Elsevier B.V., 2009)
    This article examines temporal changes in the stratification ratio of soil organic matter (SOM) for diverse tillage methods. Using a Brazilian Oxisol, the researchers evaluate whether stratification ratio is an effective index tool for carbon sequestration in soil. Ideal conditions for carbon and nitrogen cycling in the soil can be created by continually replacing the crop residues on the surface, allowing for a permanent mulch cover. Tilling and mixing the surface soil and sub-surface soil exposes SOM to microbial attach and exacerbates erosion-induced soil degradation. Therefore, stratification ratio can be an effective tool for determining soil quality and carbon sequestration capacity because it measures the SOM concentrations present in each layer of the soil.
  • Sustainable Agricultural Systems
    Edwards, C.; Lal, Rattan; Madden, P.; Miller, R.; House, G. (Ankeyn, IA: Soil and Water Conservation Society, 1990)
  • Sustainable agriculture and the international rice-wheat system
    Lal, Rattan; Hobbs, P. R.; Uphoff, N. T.; Hansen, D. O. (New York, NY: Marcel Dekker Inc., 2006-12-27)
    With contributions from 65 international authors, this book describes the rice-wheat farming system which is key to food security in South Asia. It is a compendium of information on no-till farming in South Asia in particular and the world in general, with case studies from India, Nepal, Pakistan and Bangladesh. The book is divided into seven sections. Section I is an overview section on food security and natural resources, including a chapter on prospects for world agriculture in the 21st century, one on soil and water resources in South Asia, and a third on food security and environmental sustainability. Section II, with four chapters, has the theme of no-till farming, including historical development, problems and challenges, and opportunities and constraints for future development. Section III, with six chapters, features case studies of the no-till rice-wheat system in different South Asian countries. In Section IV, the discussion of no-till farming extends to other soil-specific situations, including case studies from the USA, Brazil, Australia and Latin America. Seven chapters on social and economic issues are presented in Section V, including chapters on temperate environments, soil and water sustainability in Australia, prospects for conservation tillage in India, and policy challenges for the rice-wheat system on the Indo-Gangetic Plains. Section VI includes two chapters on networking and international cooperation, while the final section includes just one chapter (by the four editors) outlining research and development priorities. (CAB Abstract)