Soil science education – a multi-national look at current perspectives

Soil knowledge is essential to address modern global challenges. Soil science education began with soil survey and agricultural activities, with a focus on the traditional subdisciplines of soil chemistry, soil physics, pedology, soil mineralogy, and soil biology. Soil education has evolved to address the needs of an increasing variety of fields and increasingly complex issues, as seen through the move to teach soil content in programs such as biological and ecological sciences, environmental science, and geosciences. A wide range of approaches have been used to teach soil topics in the modern classroom, including not only traditional lecture and laboratory techniques but also soil judging, online tools, computer graphics, animations, and game-based learning, mobile apps, industry partners, open-access materials, and flipped classrooms. The modern soil curriculum needs to acknowledge the multifunctionality of soils and provide a suite of conduits that connect its traditional subdisciplines with other cognate areas. One way to accomplish this may be to shift from the traditional subdiscipline-based approach to soil science education to a soil functions approach. Strategies to engage the public include incorporating soil topics into primary and secondary school curricula, engaging the public through museums and citizen science projects, and explaining the significance of soil to humanity. Soil education has many challenges and opportunities in the years ahead

The importance of soil education to connectivity as a dimension of soil security

The connectivity concept within soil security posits that people need to have a connection to soil in order to properly value it. Showing how soil is important in everyday life can create connections to soil, because people care about things they see as impacting their quality of life. Education can demonstrate these connections and may take place in either formal or informal settings and over a wide range of age groups. Creating an effective educational environment is critical, which involves understanding the specific group being addressed, including their existing knowledge of and interest in soil. Soil scientists increasingly teach to student groups that need to know about soils within their chosen careers but are not necessarily training to be soil specialists. Within this formal setting, education that demonstrates the various functions that soils provide in support of human wellbeing may be important to connectivity because it clearly demonstrates the impact of soils on peoples’ lives. In less formal settings, it will be important to identify concepts that will resonate with the public or stakeholders, such as terroir, soil health, or soil security, and to effectively reach these groups with a message built around these concepts. Social marketing, social media, storytelling, soil apps, and soil games are all approaches that have promise to deliver the desired message, therefore creating connections between people and soil

Tillage-planting systems and cover cropping for sweet corn production in the Western Fraser Valley

A combination of conservation tillage and winter cover crops might reduce soil degradation problems in the western Fraser Valley. This study was conducted to determine the effects of conventional spring tillage (ST) and conservation no-spring tillage (NST) following winter wheat (Triticum aestivum L.) and spring barley {Hordeum vulgare L.) cover crops on soil physical characteristics, slug and earthworm populations, soil available N , and sweet corn (Zea mays L. saccharata Sturt.) performance. The study was carried out in 1993, 1994, and 1995 on a silty clay loam Humic Gleysol in Delta, BC. In the three years, bulk density, aeration porosity and aggregate stability were not affected by type of tillage, nor by type of cover crop. Before spring tillage there was no difference in soil penetration resistance between the two tillage systems. After spring tillage soil penetration resistance was higher in NST than in ST in the upper 15 to 20 cm of the soil profile and it ranged from 1500 to 2250 kPa. Spring barley cover crop resulted in higher soil penetration resistance than winter wheat in two out of three years. Lower soil water contents were observed at 20 cm depth with NST than with ST, while at other depths of measurement soil water contents were similar with both tillage treatments. Type of cover crop did not affect soil water content. Soil temperatures were lower by 0.4 to 1.0°C at 3 cm depth in NST than in ST during three weeks following corn planting, but NST soil temperatures were above the minimum temperature required for corn emergence and early corn growth. In the fall of 1995, earthworm population was higher in NST than in ST. At the same time, spring barley cover crop resulted in higher earthworm numbers than winter wheat. Mild winter conditions in 1993/94 and 1994/95 led to high slug populations in NST during the following spring. Slug infestation in NST plots caused serious damage to young corn plants and was one of the main reasons for the crop failure in the 1994 and 1995 seasons. Sweet corn yields were greater with ST than with NST in two out of three years, while type of cover crop did not affect sweet corn yield. Greater sweet corn response to N application was observed under winter wheat than under spring barley cover crop in 1993, and the opposite was true in 1994 and 1995. Soil NO₃concentrations were higher in NST than in ST during latter parts of 1993 and 1995 growing seasons, while in 1994 ST had higher soil NO₃than NST at corn planting. Throughout the whole 1993 growing season higher concentration of soil NO₃was observed with spring barley than with winter wheat cover crop, while in 1994 and 1995 this was true only at corn planting. Elimination of spring tillage is not the best management option for sweet corn production in this region, since it resulted in a crop failure in two out of three years of this study that was carried out on the same site. Modifications of NST practice may hold promise for successful establishment of annual crops in the western Fraser Valley.Land and Food Systems, Faculty ofGraduat

Soil compaction and water content effects on lodgepole pine seedling growth in British Columbia, SuperSoil Conf.

Abstract Increased mechanization during timber harvesting activities has led to concerns that compaction may negatively affect the long-term productivity of soil. A greenhouse study was carried out to determine the effects of soil compaction under three levels of soil water content. Mineral soil was collected from a landing in central British Columbia, Canada and lodgepole pine (Pinus contorta Dougl. ex Loud. var. latifolia Engelm.) seedlings were grown in pots for 12 weeks. Pots were compacted to densities that corresponded to 67, 72 and 76% of the Proctor maximum bulk density (1798 kg m-3) for the soil. Volumetric water contents of 0.10-0.15, 0.20-0.30 and 0.30-0.35 cm3cm-3 were maintained by weighing the pots, determining the gravimetric water content and adding the required water. Compaction only had an effect on seedling growth at low water content. Diameter growth and total shoot biomass were significantly smaller for 76% compaction compared to 67% compaction. At low water content, 76% and 72% compaction caused decreases in new root biomass and 76% compaction increased shoot macronutrient concentrations. The findings of this study imply that, for the compaction levels observed, water content had a greater impact on seedling growth than compaction

Grazing exclosures reveal divergent patterns of change in bunchgrass grasslands of Western Canada

Thirty-six long-term (14–83 years) cattle grazing exclosures and adjacent grazed pastures spanning a climatic gradient from cooler–wetter to warmer–drier growing seasons in south-central British Columbia were compared for temporal vegetation change. Trajectories of temporal vegetation change from non-metric multidimensional scaling were mostly scattered for the grazed areas, but more directed toward the dominant grasses, primarily rough fescue (Festuca campestris) or Kentucky bluegrass (Poa pratensis), for the exclosures. Plant community differences, detected only after 10 years of grazing exclusion, were primarily due to structural shifts in overall species cover related to growth increases of the dominant grasses inside exclosures. Species richness remained unchanged between the first and last sampling dates in both grazed areas and exclosures, with both treatments showing moderate degrees (15%–30%) of turnover in species composition. Shannon diversity declined in both treatments as a result of the structural changes in species cover. The results highlight the value of repeated monitoring of long-term exclosures for assessment of grassland resiliency to grazing. Further studies of the interaction of grazing and climate are needed for a more complete understanding of the ongoing vegetation change.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author

Nitrogen Dynamics Following Incorporation of 3-Year Old Grassland Set-Asides in the Fraser River Delta of British Columbia

Short-term grassland set-asides (GLSA) have been incorporated into intensive annual crop rotations to improve soil quality. The legacy of the GLSA to subsequent annual crops, however, is not well understood. The objective of this study was to determine the impacts of 3-year-old GLSA on nitrogen (N) dynamics and the yield of the subsequent cash crop. A regional analysis was conducted over two years, utilizing eight production fields transitioning from GLSA, paired with fields in continuous annual crop rotation (ACR) with matching management. A controlled plot-scale experiment was also conducted on a single 3-year-old GLSA, comparing fertilizer types, rates, and timing of incorporation. In each experiment, soils were sampled every 10–14 days for ammonium (NH₄⁺-N) and nitrate (NO₃⁻-N), along with ion probes, installed near the rooting zone to track plant available nitrogen (PAN) throughout the season. The results from the regional analysis are confounding, in 2015 showing that GLSA supplied an additional 18 kg PAN ha⁻¹ compared to ACR but showed no PAN benefits in 2016. The controlled plot-scale experiment highlighted the importance of fertilizer type to subsequent PAN, showing synthetic treatments consistently supplied more PAN than organic. The results from this study suggest that 3-year-old GLSAs can potentially improve PAN to subsequent crops depending on how they are managed.Forestry, Faculty ofLand and Food Systems, Faculty ofNon UBCForest and Conservation Sciences, Department ofReviewedFacult

Short-term Effects of Grassland Set-Asides on Soil Properties in the Fraser River Delta of British Columbia

Grassland set-asides (GLSA) in the Fraser River delta are fields that are taken out of crop production and seeded with a mixture of grasses and legumes for one to four years. During this time, the farmer is compensated with a cost-share payment to recover a portion of the financial returns that could have been earned from cash crops. The objectives of this study were to (i) evaluate the effects of GLSA on soil properties during the initial two seasons of enrollment, (ii) determine how GLSA effects differ between fields that were considered productive and unproductive, and (iii) identify soil baseline indicators and preliminary soil thresholds for predicting GLSA vegetation responses. Out of eight fields entering the program, two were considered to be unproductive and exchangeable sodium had the strongest negative relationship to GLSA aboveground biomass (r= -0.61, P=0.0002). During the second season of GLSA establishment, the mean weight diameter of water-stable soil aggregates was consistently higher in productive GLSAs than paired annual crop rotation (ACR) fields, being 21% higher in April, 14% in July, and 19% in September after crop harvest. After two seasons of GLSA enrolment, both aeration porosity and bulk density were improved by GLSA relative to ACR fields with aeration porosity being 24% greater and bulk density 7% lower in GLSA. The results suggest that GLSA rotations in productive agricultural fields within the Fraser River delta provide an alternative to continued ACR that can improve soil structure and reduce compaction after only two seasons of establishment.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author

Comparison of Selected Soil Properties following Grassland Set-Aside and Annual Crop Rotations in the Fraser River Delta of British Columbia

Selected soil properties were compared after two to six years of grassland set-aside (GLSA) management and an annual cropping system (potato). Generally, GLSA and nearby arable copping fields had similar soil properties, with some improvements of aeration porosity, aggregate stability, bulk density and mechanical resistance following short-term GLSA management.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author

Introductory Soils Courses: A Frontier of Soil Science Education in Canada

As the focus of soil science education in Canada and elsewhere has shifted towards non-soil science majors, it is important to understand if and how this has affected the scope of introductory soil science courses. The objectives of this study were to inventory Canadian postsecondary units that offer introductory soil science courses and to document attributes of instructors, students, and teaching approaches in these courses. We surveyed 58% of the instructors of introductory soil science courses across Canada, and most of these courses were offered by geography and environmental science units. The majority of instructors followed a traditional lecture (86%) and laboratory (76%) delivery format, while 36% used online teaching resources. Introductory courses were delivered by primarily one instructor, who held a PhD in a tenure track position and in most cases developed the course themselves. Over half of the instructors surveyed used either a required or a recommended textbook; pointing to the need for creation of a Canadian-authored soil science textbook. Several follow-up studies are needed to evaluate teaching methods used in the upper level soil science courses, studentâ s perceptions of teaching in soil science, and instructorsâ knowledge of resources available for online and/or blended learning.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author

Soil productivity and forest regeneration success on reclaimed oil and gas sites in the Dawson Creek Forest District

We visited 27 reclaimed oil and gas well sites in northeast BC that were decompacted and planted with lodgepole pine between 1994 and 1999. The reclamation work was carried out as part of an effort to gain experience with reforestation as a potential strategy for improving abandoned oil and gas sites. Reclamation techniques included decompaction either with a winged subsoiler or a ripper, seeding a cover crop, fertilizing, and planting to lodgepole pine, which has previously been successful in reclamation of forestry disturbances. Of the 27 sites, three (11.1 percent) had been re-used by drilling rigs, and an additional site was re-used as a forest landing. We evaluated tree growth on 19 of the well sites, and collected detailed information on vegetation cover, ecological and soil conditions. Clay content for the sampled sites ranged from 0 to 40 percent and bulk density from 594 to 1803 kg/m³. Soil chemical properties (C, N, available P, pH) were very similar to conditions found on nearby forest plantations and rehabilitated landings. Values of soil mechanical resistance in the rooting zone during July exceeded values that are expected to be growth-limiting on several plots, but values in June were below the threshold of 2500 kPa. Approximately 50 percent of the plots had stocking levels above 600 stems per hectare. Subplots with subhydric, hygric and subhygric moisture regime appeared to have generally lower stocking levels than subplots with mesic and submesic moisture regime. Average stocking levels for well sites were lower than for rehabilitated forest landings and undisturbed plantations on similar sites in the BWBS, and the trees on the well sites were smaller than trees planted on landings that had similar site conditions. Field observations suggested that factors such as competition from seeded cover crops, moisture regime, selection of tree species, and well site construction / rehabilitation techniques affected seedling survival and growth on individual sites. Where soil and site conditions are suitable, tree planting appears to be a useful technique that would enhance environmental values over the long term. To obtain the maximum benefit from reforestation efforts on well sites, a targeted approach is suggested, where efforts are directed at sites with the highest likelihood of success. This operational reforestation work has provided some key lessons that can be used to improve reforestation success on reclaimed oil and gas sites in the future.Land and Food Systems, Faculty ofNon UBCUnreviewedOthe