According to Self-Determination Theory, teachers can enhance their students’ motivation, engagement, and learning through need-supportive teaching, which involves providing autonomy support,... Show moreAccording to Self-Determination Theory, teachers can enhance their students’ motivation, engagement, and learning through need-supportive teaching, which involves providing autonomy support, structure, and involvement. However, within classes, there appears to be great variation in the degree to which teachers support students’ psychological needs. The current studies aimed to investigate to what extent this differentiation in need support was associated with students’ socioeconomic background. Additionally, we examined whether teachers differentiated their need support more strongly when they had more biased Explicitly or Implicitly measured attitudes toward students from a low socioeconomic background. We conducted two studies: Study 1 was a vignette study representing a fictional student from a high or low socioeconomic background, and Study 2 was a field study where teachers reported on the need support provided to real students from a high and low socioeconomic background from their own class. Findings of both studies indicated that teachers reported lower levels of involvement for students from a low compared to a high socioeconomic background. Moreover, in Study 2, teachers reported to provide students from a low socioeconomic background with less autonomy support and more structure compared to students from a high socioeconomic background. However, these differences in autonomy support and structure seemed to be related to other student characteristics, namely students’ gender, and teachers’ perceptions of students’ academic ability and classroom behavior. Furthermore, we revealed that teachers differentiated their need support more strongly when they had more biased attitudes toward low socioeconomic backgrounds. Show less
Reactive nitrogen (N) losses, and in particular nitrous oxide losses, from dairy grasslands on peat soils are generally high as a result of relative high soil organic matter contents, potential N... Show moreReactive nitrogen (N) losses, and in particular nitrous oxide losses, from dairy grasslands on peat soils are generally high as a result of relative high soil organic matter contents, potential N mineralisation rates and shallow groundwater levels. Effects of the inclusion of the temperate forage species plantain (Plantago lanceolata L.) (PL), which produces secondary compounds with biological nitrification inhibition capacity, on the fate of soil mineral N were studied in a combined mesocosm and field experiment. The experiments comprised four treatments differing in intentional herbage share of plantain versus perennial ryegrass (Lolium perenne L.) (100%PL, 66%PL, 33%PL and 0%PL). Potential nitrification in the mesocosm experiment was significantly lower at 100%PL versus 0%PL (p = 0.018), but soil nitrate concentrations were not. Nitrous oxide fluxes reduced by 39% (p = 0.021) in the presence of plantain in the field experiment, without an obvious link to the quantity of plantain. N use efficiency of plantain tended to increase with the quantity of plantain in the sward in the mesocosm experiment (p = 0.098), but not in the field experiment. Our results suggest that the presence of plantain can affect the fate of soil mineral N of dairy grasslands on peat soils. Show less
Kouijzer, I.; Scheper, H.; Rooy, J. de; Bloem, J.; Janssen, M.; Ioven, L. van den; ... ; Oel, L.D. 2017
