cross-cutting activities: soil quality (prepared by peter motavalli) soil metagenomics

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Soil degradation is a major global environmental problem, resulting in increased poverty and severe environmental problems (e.g., decreased biodiversity and water quality) (Eswaran et al., 1997).Soil degradation is a major global environmental problem, resulting in increased poverty and severe environmental problems (e.g., decreased biodiversity and water quality) (Eswaran et al., 1997). For example, the loss of potential productivity due to soil erosion world wide is estimated to be equivalent to some 20 million tons of grain per year (UNEP, 1999).For example, the loss of potential productivity due to soil erosion world wide is estimated to be equivalent to some 20 million tons of grain per year (UNEP, 1999). INTRODUCTION

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Cross-cutting activities: Soil quality (prepared by Peter Motavalli) Soil metagenomics Peter Motavalli, Bunjirtluk Jintaridth, Johannes Lehmann, Keith Goyne, and Jere Gilles ASSESSING AND MANAGING SOIL QUALITY FOR SUSTAINABLE AGRICULTURAL SYSTEMS SANREM-CRSP CROSS-CUTTING INITIATIVE Soil degradation is a major global environmental problem, resulting in increased poverty and severe environmental problems (e.g., decreased biodiversity and water quality) (Eswaran et al., 1997).Soil degradation is a major global environmental problem, resulting in increased poverty and severe environmental problems (e.g., decreased biodiversity and water quality) (Eswaran et al., 1997). For example, the loss of potential productivity due to soil erosion world wide is estimated to be equivalent to some 20 million tons of grain per year (UNEP, 1999).For example, the loss of potential productivity due to soil erosion world wide is estimated to be equivalent to some 20 million tons of grain per year (UNEP, 1999). INTRODUCTION Almost 75% of Central Americas, 45% of South Americas, and 11% of Asias agricultural land have been seriously degraded. (Scherr, 1999; Heerink, 2001).Almost 75% of Central Americas, 45% of South Americas, and 11% of Asias agricultural land have been seriously degraded. (Scherr, 1999; Heerink, 2001). Three-quarters of Africas farmland has severe soil degradation caused by wind and soil erosion and loss of mineral nutrients (Heano and Baanante, 2006).Three-quarters of Africas farmland has severe soil degradation caused by wind and soil erosion and loss of mineral nutrients (Heano and Baanante, 2006). INTRODUCTION (CONT.) Definition : the capacity of a soil . to sustain biological productivity, maintain environmental quality, and promote plant and animal health (Doran and Parkin,1994). SOIL QUALITY Soil quality depends on the capacity of a soil to perform a desired ecosystem functionSoil quality depends on the capacity of a soil to perform a desired ecosystem function Soil functions Soil functions sustaining biological activity, diversity, and productivity regulating and partitioning water and solute flow filtering, degrading, immobilizing and detoxifying organic and inorganic species storing and cycling of nutrients providing structural support SOIL QUALITY (CONT.) Biological indicators (e.g., microbial community structure and activity)Biological indicators (e.g., microbial community structure and activity) Chemical indicators (e.g., pH, CEC)Chemical indicators (e.g., pH, CEC) Physical indicators (e.g., infiltration, bulk density, water-holding capacity)Physical indicators (e.g., infiltration, bulk density, water-holding capacity) Soil organic matter is an important soil quality index because of its integral role in soil biological, physical and chemical processes (Carter, 2002)Soil organic matter is an important soil quality index because of its integral role in soil biological, physical and chemical processes (Carter, 2002) SOIL QUALITY (CONT.) USDA Soil Quality Test Kit Assess community perceptions and indicators of soil quality, including differences in perceptions of soil quality due to gender, environment and socio-economic factors.Assess community perceptions and indicators of soil quality, including differences in perceptions of soil quality due to gender, environment and socio-economic factors. Determine the effectiveness of spectroscopic- based (i.e., near-infrared, mid-infrared, and visible range) analytical methods to evaluate soil organic matter fractions and soil quality in degraded and non-degraded soils in a wide range of environments.Determine the effectiveness of spectroscopic- based (i.e., near-infrared, mid-infrared, and visible range) analytical methods to evaluate soil organic matter fractions and soil quality in degraded and non-degraded soils in a wide range of environments. To collaborate in the evaluation of soil metagenomic methods as an indicator of soil degradation.To collaborate in the evaluation of soil metagenomic methods as an indicator of soil degradation. OBJECTIVES Will use participatory workshops of community members and professionalsWill use participatory workshops of community members and professionals What are the specific soil quality indicators that community members use to evaluate soil quality among the different soil types and crops?What are the specific soil quality indicators that community members use to evaluate soil quality among the different soil types and crops? How has soil quality changed over time and why?How has soil quality changed over time and why? The communities will be surveyed to determine the characteristics of a field soil quality testing procedure that would be appropriate for their conditions and for evaluating sustainable agricultural management practices.The communities will be surveyed to determine the characteristics of a field soil quality testing procedure that would be appropriate for their conditions and for evaluating sustainable agricultural management practices. METHODOLOGY COMMUNITY PERCEPTIONS OF SOIL RESOURCES AND SOIL-RELATED PROBLEMS IN BOLIVIA Soil-related problems are only one of several factors limiting crop production.Soil-related problems are only one of several factors limiting crop production. Soil management problems identified were:Soil management problems identified were: Low soil quality and soil fertility (low soil nutrient content, high clay content and stoniness) Low soil quality and soil fertility (low soil nutrient content, high clay content and stoniness) Excessive water and wind-induced soil erosion Excessive water and wind-induced soil erosion Insufficient soil moisture due to lower rainfall Insufficient soil moisture due to lower rainfall Inadequate soil management practices (Inappropriate tractor tillage practices, lack of a suitable crop rotation strategy, insufficient soil fertility inputs, and overgrazing by sheep) Inadequate soil management practices (Inappropriate tractor tillage practices, lack of a suitable crop rotation strategy, insufficient soil fertility inputs, and overgrazing by sheep) Soils will be collected from depths of 0-10 to cm from degraded and non-degraded agricultural fields (i.e., Sanborn Field, Bolivian, Ecuadorian, Zambian, and Asian studies)Soils will be collected from depths of 0-10 to cm from degraded and non-degraded agricultural fields (i.e., Sanborn Field, Bolivian, Ecuadorian, Zambian, and Asian studies) The soil will be freeze-dried, ground and sieved to a size fraction