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This article explores undergraduates' efforts to engage in scientific argumentation during exam settings. Thirteen undergraduate students enrolled in an environmental science course completed exams with questions linked around a central theme. Three types of questions were used, including those that prompted students to construct scientific arguments. Structural questions asked students to define or describe foundational concepts, whereas functional questions targeted students' understanding of relationships between topics. Argumentative questions tasked students with applying their understanding of soil science to everyday situations, which connected to the course's overarching goals for student learning. Though each type of question was linked to a central theme (e.g., soil nutrient exchange), the questions prompted students to engage in different cognitive processes. Using linked questions provided a strong forum for students to showcase their level of understanding of soil science. Implications for using these types of questions in an exam setting are discussed.

This article describes current practices and needs associated with water and gas conservation among Southern California greenhouse growers, Post-Harvest Processors (PHPs), and agricultural associations. Two communication forums were held with the goal of educating the local gas company and small growers and PHPs on the most compelling needs and best practices to support sustainability while improving profit. While some growers and PHPs have made significant investment in energy and water conservation advanced technologies, all participants expressed the desire to work with local utilities towards greater water and energy conservation opportunities that are customized to specific needs.

Both climate and plant species are hypothesized to influence soil organic carbon (SOC) quality, but accurate prediction of how SOC process rates respond to global change will require an improved understanding of how SOC quality varies with mean annual temperature (MAT) and forest type. We investigated SOC quality in paired hardwood and pine stands growing in coarse textured soils located along a 22 °C gradient in MAT. To do this, we conducted 80-day incubation experiments at 10 and 30 °C to quantify SOC decomposition rates, which we used to kinetically define SOC quality. We used these experiments to test the hypotheses that SOC quality decreases with MAT, and that SOC quality is higher under pine than hardwood tree species. We found that both SOC quantity and quality decreased with increasing MAT. During the 30 °C incubation, temperature sensitivity ( Q10) values were strongly and positively related to SOC decomposition rates, indicating that substrate supply can influence temperature responsiveness of SOC decomposition rates. For a limited number of dates, Q10 was negatively related to MAT. Soil chemical properties could not explain observed patterns in soil quality. Soil pH and cation exchange capacity (CEC) both declined with increasing MAT, and soil C quality was positively related to pH but negatively related to CEC. Clay mineralogy of soils also could not explain patterns of SOC quality as complex (2 : 1), high CEC clay minerals occurred in cold climate soils while warm climate soils were dominated by simpler (1 : 1), low CEC clay minerals. While hardwood sites contained more SOC than pine sites, with differences declining with MAT, clay content was also higher in hardwood soils. In contrast, there was no difference in SOC quality between pine and hardwood soils. Overall, these findings indicate that SOC quantity and quality may both decrease in response to global warming, despite long-term changes in soil chemistry and mineralogy that favor decomposition. [ABSTRACT FROM AUTHOR]