| | 1.0 Introduction
This report describes the micronutrient and trace element status of the AESA (Alberta Environmentally Sustainable Agriculture) Soil Quality Benchmark Sites. Previous reports completed for this study include:
- Baseline soil physical and chemical properties of forty-three soil quality benchmark sites in Alberta.
- Preliminary statistical analysis of baseline soil organic carbon and nitrogen data of forty-three soil quality benchmark sites in Alberta.
- Preliminary statistical analysis of baseline soil fertility data of forty-three soil quality benchmark sites in Alberta.
- Micronutrient (Cu, Fe, Mn, and Zn) status of forty-three soil quality benchmark sites in Alberta.
- Analyses of five years of soil data from the AESA soil quality benchmark sites.
This ongoing study includes forty-three benchmark sites distributed across the agricultural regions of Alberta. The sites are located in seven ecoregions, namely: Peace Lowlands (PL); Mixed Boreal Upland (MB); Boreal Transition (BT); Aspen Parkland (AP); Moist Mixed Grassland (MM); Fescue Grassland (FG) and Mixed Grassland (MG). These ecoregions fall within the Boreal Plains and Prairie ecozones (Figure 1). A description of the ecoregions can be found in A National Ecological Framework for Canada (Ecological Stratification Working Group, 1995). Each site has been characterized in detail with respect to landform, soil profile and physical and chemical properties at an upper, mid, and lower slope position along a catena (Report No. 1 above). Historical management information was recorded and information on current management practices is collected each year from the cooperating farmers. Soil and crop samples are taken from upper, mid and lower slope positions each year to monitor soil fertility, crop yield and nutrient uptake.
Soil samples taken in the fall of 2002 were analyzed for thirty elements. This report describes the influence of ecoregions, soil properties, and historic management practices on boron (B), chloride (Cl), cobalt (Co), molybdenum (Mo), nickel (Ni), silicon (Si), chromium (Cr), cadmium (Cd), and selenium (Se) [Appendix 1 and 2]. The data for the additional twenty-one elements are presented in Appendices 3 and 4, but are not discussed in this report. Report Number 4 above discusses the results of copper, iron, manganese, and zinc analyses on samples taken in 2000.
This broad scan of the micronutrient and trace element status of the Soil Quality Benchmark Sites provides useful baseline information regarding the variability and range of element concentrations within ecoregions, soil types and landscapes. However, the literature for many of the elements does not provide a basis to assess their status as deficient, normal or high. Of the nine elements discussed in this report, only B and Cl are routinely analysed in this region (the Northern Great Plains). There is limited information for some of the other elements, but generally not for the extraction methods used in this study. |
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